Forty seven years in the TV, entertainment arts industry. Commencing his career at HSV 7 Melbourne as a trainee in 1970. Apart from his involvement on Hey Hey's Saturday. He became Australia's first Freelance TV Audio Operator in 1978 as well as a Freelance Film Sound Recordist, and through these experiences he gained great insight in the audio industry. An entrepreneur to the sound rental industry and a pioneer in many fields of communication and digital recording. It can truly be said that Murray has changed the face of the production sound industry in Australia.
Forty years in the TV, entertainment and arts industry culminating in the position of Head of Audio at NWS9 in Adelaide. Major events include the initial Adelaide F1 Grand Prix coverage and subsequent years. Brian has extensive technical knowledge and experience in all facets of the industry but specialising in live TV and Outside Broadcast sound production. Brian relocated to Sydney in 2001 to become the Manager of our MatchCom Referee Communication operations for the National Rugby League and Australian and NZ Rugby. In 2004 Brian was promoted to NSW State Manager, and then General Manager and as such manages all aspects of our day to day operations.
Tony brings a wealth of Industry experience to the Company having commenced his career in the Audio Department of HSV 7 Melbourne in 1972. He rose to become the Head of Audio, a role he maintained for over Ten Years. During his time at HSV 7 he was involved in the planning, staffing and operation of many major TV events, both Studio and Outside Broadcast. After 16 Years with HSV 7 he moved to EAV Technology as National Sales Manager, Broadcast/AV Products. This role saw Tony gain extensive experience in all facets of the equipment supply & support area.
Christian joined MT&A in 2005 as NSW Audio Rental Manager after 10 years working as a location sound recordist and audio professional in the film & TV industry.
In 2007 he moved into the NSW Sales Manager Role and in 2010 made the move north to manage our Queensland office. This role see's Christian working across all facets of the business including Sales, Rentals and Sports Operations.
Murray Tregonning & Associates was founded in 1978, by the charismatic man himself, Murray Tregonning. Having made his name as the lead audio operator for Hey Hey It's Saturday for 22 years of its 28 year record run on Australian TV. He built the company with his main goal of consulting and providing the latest and best in professional audio, communications and tele-prompting equipment for the TV broadcast industry.
Since 1978, MT&A has grown steadily to having main offices in Melbourne, Sydney and Brisbane, while maintaining affiliates in other states as well as New Zealand and the United Kingdom.
Throughout its history, MT&A has strived to offer our clients the best advice on renting or purchasing anything related to audio recording, broadcasting, talkback or signal distribution. This advice and service has extended to having active roles in many of our clients projects. As a result of this, we expanded our business to include technical project design and management. Utilising the extensive experience of our staff of broadcast and entertainment professionals. The great strength of MT&A's people is our ability to offer creative solutions to our clients' challenges. Whatever the project, we can help design and co-ordinate technical solutions to turn ideas into reality.


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Two pilots ejected as Royal Navy jet crashes in Cornwall
by Molly Gray | Mar 25, 2021 | SCOOPFal | 0 comments
Two pilots were ejected from a Royal Navy Hawk jet near the Lizard this morning.
A large number of emergency service members at the scene. Credit: Cornwall_in_Focus/Richard Cooper
The jet, which left the 736 Naval Squadron based at RNAS Culdrose, crashed in the St Martin area after pilots ejected from the aircraft.
The pilots were air lifted to hospital by Cornwall Air Ambulance, with South Western Ambulance also attending the scene.
A local farmer went to assist the pilots and reported that they "seemed ok" when he found them in a nearby field, and it is said that their injuries are not expected to be life threatening or changing.
Richard Cooper, an eyewitness, also said that there was a "strong smell of fuel".
A Royal Navy Hawk aircraft of 736NAS crashed during a flight from RNAS Culdrose in Helston
Defence Minister Johnny Mercer said that the crash was due to "suspected engine failure", and the MOD reported on Twitter that they will begin an investigation "in due course".
It was the first Royal Navy ejection for 18 years, according to the manufacturer of the ejection seats.
Witnesses said that they heard loud bangs, which was later revealed to be the noise of the pilots ejecting.
For live updates, click here.

redpajama_set_name: RedPajamaCommonCrawl


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Compliance : Sarbanes Oxley : Privacy Management :
Andrew Serwin Joins Board of National Cyber-Forensics and Training Alliance
Prominent nonprofit and its partners exercise global reach in fighting cybercrime; Serwin is an internationally recognized authority on privacy and information security
Andrew Serwin
Global Privacy and Data Security Practice Group Partner
Morrison & Foerster
Morrison & Foerster Global Privacy and Data Security partner Andrew Serwin has been named to the board of directors of the National Cyber-Forensics and Training Alliance (NCFTA), a U.S.-based organization that works with government, private industry, academia, and law enforcement to study, counteract, and prevent cybercrime.
Mr. Serwin, resident in Morrison & Foerster's Washington, D.C. and San Diego offices, begins his term on the board in September.
The NCFTA was established in 2002 to develop intelligence and share information with its partners as part of the international effort to fight cybercrime. Based in Pittsburgh, the organization has aided in the successful prosecution of more than 300 cyber-criminals worldwide and produced more than 800 reports on global cyber threats.
The NCFTA board includes executives from the telecom, accounting services and financial industries, as well as higher education. The board advises organization CEO Maria Vello as part of facilitating overall cooperation against cybercrime among law enforcement, private industry, and government.
The organization has a number of current initiatives, including those targeting online financial crimes, consumer protection and the prevention of online fraud and counterfeiting, and malware. The NCFTA emphasizes that cybercrime can also support and enable current crises, including human and drug trafficking, terrorist activities, child exploitation, and other illicit activities.
"Our greatly increased dependence, in virtually every facet of life, on the Internet has made it easier for cyber criminals to disrupt and steal—from personal identities to corporate and state secrets," says Mr. Serwin. "No one can or should go it alone in fighting cyber crime. A collective response marshaling intelligence and experience from business, governments, academia and more is required, which is where NCFTA serves such a useful purpose in fostering collaboration and information-sharing. I'm honored to join the board, and look forward to partnering with other leaders in the ongoing international struggle against cybercrime."
Mr. Serwin is an internationally recognized consumer protection and privacy lawyer, as well as a thought leader regarding information, and its role in society and the economy. He advises large and small companies on global privacy compliance and technology transactions, and has litigated cases before the Federal Trade Commission and the Office of Civil Rights.
Mr. Serwin is also CEO and executive director of the Lares Institute, a Southern California-based think tank focused on information management issues. He is also a member of the advisory team of the Naval Postgraduate School's Center for Asymmetric Warfare and is an international advisory council member of APCO Worldwide, a global communication and business strategy firm. Security magazine named Mr. Serwin to its list of the "25 Most Influential Industry Thought Leaders." He is the only lawyer at a private law firm lawyer ever to receive such recognition.
ABOUT MOFO
We are Morrison & Foerster — a global firm of exceptional credentials. Our clients include some of the largest financial institutions, investment banks, Fortune 100, technology and life sciences companies. We've been included on The American Lawyer's A-List for 11 straight years, and the Financial Times named the firm number six on its list of the 40 most innovative firms in the United States. Chambers USA has honored the firm with the only 2014 Corporate/M&A Client Service Award, as well as naming it both the 2013 Intellectual Property and Bankruptcy Firm of the Year. Our lawyers are committed to achieving innovative and business-minded results for our clients, while preserving the differences that make us stronger.
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A continuously variable rearview mirror system (10) includes a reflective element (28) having a reflectance condition that varies as a function of the amplitude of a signal applied to the element. Forward and rearward facing light sensors (12,14) receive light independent of the reflectance condition of the mirror and produce an ambient light signal and a signal indicative of light directed into the reflective element. A control circuit (13) includes a difference amplifier (20) that is responsive to the ambient and rearward light signals for producing an output signal that is a function of the arithmetic difference between the ambient and rearward light signals multiplied by the gain of the difference amplifier. The control circuit produces a family of constant-reflectance curves which model an ideal response over all relevant ambient light levels. Offset circuits are provided to allow the relationship between the output signal from the control circuit and the drive signal applied to the reflectance element to be preselected to accommodate various types of reflectance elements and to fine-tune the response of the drive signal applied to the reflectance element.
This invention relates to rearview mirrors that automatically adjust to the level of light reflected by a reflectance element. The invention is especially adapted for use with such a mirror having a reflectance element whose reflectance is continuously variable, within limits, in response to an electrical signal applied thereto. More particularly, the invention concerns a mirror in which the reflectance element is an electrochromic cell.
It is well-known to provide a rearview mirror for a vehicle having a control which adjusts the reflective condition of a reflective element in response to the ambient light level, sensed by a forward facing sensor, and the level of light directed at the reflectance element from the rear of the vehicle, or glare, sensed by a rearward facing sensor. One such automatic rearview mirror utilizes a prism-type reflective element, which is substantially identical with that used in manually-operated day-night mirrors provided on vehicles. The mirror control establishes either a high reflectance condition, when the rearward signal is below a level established by the ambient light signal, or a low reflectance condition, when the rearward signal is above the threshold level. Such mirrors have numerous difficulties including the availability of only two reflectance conditions and the annoyance of either frequent mirror flipping or being in the incorrect reflectance mode. An example of such a mirror is US-A-3,601,614, issued to Platzer.
An improved mirror includes a continuously variable reflectance element that is electrically stimulated to alter the light transmittance value of a variable light attenuating layer rather than provide flipping between mechanical states. The reflectance condition of the mirror is typically determined by positioning a light sensor where it will receive light directed from the rear of the vehicle and which has been attenuated by the variable light attenuating layer. This is typically accomplished by removing the reflective coating from a portion of the mirror and positioning the sensor on a forward portion of the mirror where the reflective coating has been removed, such that light striking the sensor from the rear of the vehicle is attenuated by the variable light attenuating layer. A control responds to the attenuated rearward light signal and a setpoint signal, typically established by an ambient light sensor, to vary the electrical signal stimulating the variable light attenuating layer until the rearward light signal equals the setpoint signal. Thus, such control is said to operate in a closed control loop because changes in the output variable (transmittance value of the variable attenuating layer) are detected by an input device (rearward light sensor) to restore balance to the system. While such a mirror control avoids many difficulties of the mechanical prismatic mirror, the removal of a portion of the reflective coating produces a noticeable spot on the mirror which appears as a blemish to the user. An example is US-A-4,603,946, issued to Kato et al.
Controls for mirrors having continuously variable reflectance elements have been proposed which avoid the use of rearward facing sensors positioned opposite the light attenuating layer. Such controls are said to operate in an open-loop mode because the input light sensors are not apprised of changes in the output variable. One such open-loop control is suggested in EP-A-0,285,724 of Jon H. Bechtel. Although this application is primarily directed to closed-loop controls, in one embodiment it is suggested that the rearward, or glare, light sensor may be made independent of the condition of the variable light transmittance layer by making modifications to a closed-loop control circuit. While this application purports to produce an output voltage which causes the transmittance of the light attenuating layer to assume the ideal value for the level of glare directed at the mirror, the actual test data set forth in the application demonstrates performance at only one ambient light level. The important measure of performance requires an ideal response over a wide range of ambient levels.
Another difficulty with electrochromic cells is the slow time response to a command for a change in the reflective condition of the mirror. It is not uncommon for an increase in the reflectivity from a 10% to a 60% reflectivity value to require eight seconds. A colouration of the cell from 70% to 20% reflectivity typically requires four seconds. When a sudden increase in glare is experienced by the mirror, the slow time response in decreasing the reflectivity can result in an unacceptably long period of time in which the light level reflected into the driver's eyes exceeds the glare tolerance level. This characteristic of electrochromic cells is even more noticeable in open loop controls in which the drive signal for the electrochromic cell varies within a small range even for abrupt changes in the desired reflectivity of the mirror. Thus, the true potential of the variable reflectance mirror remains unrealized.
The invention is set out in the accompanying claims, preferred but optional features being included in the dependent claims. To assist in understanding, there will now follow a non-limiting discussion of various aspects of the invention and preferred features and embodiments thereof.
The present invention provides an automatic rearview mirror control that produces infinite variability of the reflectance of a reflective element in a manner that models an ideal response. Such a mirror is provided with an open-loop control which does not require an uncoated spot in the reflective element and avoids the need for costly circuit components. According to one feature of the invention, an automatic rearview mirror system for a vehicle includes a reflective element having a reflectance condition that varies as a function of the amplitude of a signal applied to the element. The mirror system further includes an ambient light signal generating means for producing an ambient light signal indicative of the ambient light and a rear light signal generating means for producing a rear light signal indicative of light rear of the vehicle, or glare. The mirror system further includes control means responsive to the ambient and rear light signals for producing an output signal that is a function of the difference between the ambient and rear light signals and is substantially independent of the reflectance condition of the reflective element. The control, accordingly, operates in an open-loop mode. Importantly, such a control very closely matches the ideal response for all relevant ambient light levels.
According to a preferred feature of the invention, the control means is a difference amplifier and includes gain establishing means for establishing a gain value such that the signal applied to the mirror is a product of the gain and the difference between the ambient light signal and the rear light signal. The gain value may, therefore, be selected to cause the signal applied to the variable reflectance element to have a value with respect to the difference between the ambient and the rear light signals, that matches the performance characteristics of the variable reflectance element. In this manner, differences in slope of the reflectance versus voltage curve of various electrochromic cells may be accommodated by adjusting only one parameter of the circuit.
According to another preferred feature of the invention, biasing means are provided for adjusting the relationship between the ambient and rear light signals and the amplitude of the signal applied to the variable reflectance element to accommodate differences, other than slope of the reflectance vs voltage curve, between various types of electrochromic cells. Such biasing means may further provide selection of the shutoff, or full reflectance, signal level applied to the variable reflectance element.
According to yet another preferred feature of the invention, drive means are provided for applying an input signal to the reflective element as a function of the desired reflectance condition of the mirror. The drive means includes means for temporarily offsetting the input signal from a value that corresponds to the desired reflectance condition of the reflective element to increase the rate of change of the reflectance condition of the reflective element. Because the offset is temporary, the input signal to the reflective element is at the appropriate level for the desired reflectance condition before the reflective element colours or bleaches to that level. Additionally, it has been discovered that the maximum safe operating voltage of the reflectance element may be temporarily exceeded by this method to speed up the change of the reflectance element from a maximum to a minimum reflectance condition or vice versa. The temporary offset of the input signal is in the direction of change of the input signal in either an increasing or a decreasing reflectance condition to increase the speed of coloration and bleaching of the variable reflectance element.
Fig. 12 is a schematic diagram of an electrical control circuit combining various features of the invention.
A mirror system 10 includes a housing 11 which encloses a variable reflective element 28 and a control circuit 13. Mounted to the exterior of housing 11 is a forward light sensor 12 which receives light from a direction of the vehicle other than the rear. A second light sensor 14 is mounted to the exterior of housing 11 facing the rear of the vehicle, which is the same direction from which glare-causing light, which is reflected by reflective element 28 to the driver, is received. A sensitivity adjusting device 15 extends through the housing to allow the driver to adjust the response of the mirror to glare. Light sensors 12, 14 and sensitivity adjustment device 15 are received as inputs to circuit 13. Supply voltage from the ignition of the vehicle is received on lines 110, 111. Output lines 24, 25 from circuit 13 provide a drive signal to terminals 26, 30 of a variable light attenuating layer 27 of variable reflectance element 28. The amplitude of the voltage across lines 24, 25 determines the light transmittance value of layer 27. Because light is transmitted twice through layer 27, the amount of light attenuated by layer 27 will determine the amount of light reflected by reflectance element 28. In the illustrated embodiment, variable reflectance element 28 is an electrochromic cell which may be either electrochemichromic or a cell having thin-film electrochromic coatings. However, the invention may be applied to any cell whose light transmittance is a function of the electrical signal applied to its terminals.
Forward and rear signal lines 16, 18 are connected respectively to the noninverting input 17 and inverting input 19 of a differential input operational amplifier 20. Amplifier 20 produces an analog voltage on its output 24 which is proportional to the arithmetic difference of the ambient light signal on line 16 and the rear light signal on line 18. The gain of amplifier 20 is proportional to the resistance value of a feedback resistor 22, extending between output 24 and rearward light signal line 18. The resistance value of feedback resistor 22 is such that amplifier 20 will operate in a non-saturated, or linear, mode. The signal developed on output line 24 is thus equal to the arithmetic difference between the analog voltage on line 16 and the analog voltage on line 18 multiplied by a gain value that is established by the resistance value of resistor 22.
A first constant offset circuit 21 provides biasing means to increase the level of the signal on line 16 by a fixed DC offset that is preselected to adjust the value of the output signal on line 24 to a predetermined value when the level of light sensed by forward and rear sensors 12 and 14 are equal. This predetermined voltage value is shown at point 21 in Fig. 3 as the point where the change of reflectance with respect to the amplitude of the applied drive signal, which is the slope of the illustrated curve, changes from more gradual to more steep.
The output of amplifier 20 on line 24 is connected to terminal 26 of light attenuating layer 27 of variable reflectance element 28. The other terminal 30 is connected with signal ground through a second constant offset circuit 23. Offset circuit 23, which is shown for illustration purposes as a battery, whose positive terminal is connected with terminal 30 and whose negative terminal is connected with signal ground 31, provides a positive DC offset to cell 28. The effect of offset circuit 23 is to adjust the relationship between the level of voltage produced on output line 24 and the voltage applied across terminals 26, 30. This has the effect of shifting the entire reflectance versus voltage curve illustrated in Fig. 3 to the left or right with respect to the coordinates shown. This provides a convenient technique to apply, for example, a negative voltage across terminals 26, 30 when it is desired to place the reflectance element in a maximum reflectance condition.
Bright light reflecting into the eyes of a driver during night driving can seriously impair forward vision. Ideally, the reflective level, or reflectance, of the rearview mirror should be just low enough to keep reflected glare below the disability level. This would give the driver maximum visibility as well as glare protection. Additionally, changes in the (logarithm of) intensity of glare would produce the same effect, in an ideal mirror, for one ambient light level as an equally-sized shift in the same direction at any ambient light level. This ideal model is illustrated in Fig. 4 in which the logarithm of the ambient light intensity is charted against the logarithm of the light intensity incident the mirror from the rear of the vehicle, or glare. The lines, which indicate a particular value of constant reflectance for the reflective element, are illustrated as parallel lines that are equally offset from each other. Thus, regardless of the level of ambient light, a change in the log of glare intensity will produce a consistent change in the reflectance of the reflective element. It should be observed that the slope of the parallel lines in Fig. 4 flatten out at very low levels of ambient light because the eye's tolerance to glare does not change significantly below a certain level of ambient light. Likewise, the slope of the lines in Fig. 4 become steep at very high levels because the eye becomes insensitive to glare above a certain high level of ambient, such as daylight.
C,B and D are constants that vary with the individual, depending on eye sensitivity to light, age and the like.
If VG is the signal level produced by rearward light sensor 14 and VA is the signal level produced by forward light sensor 12 then it is desired that a curve having the slope of one of the family of curves in Fig. 4 be produced when VA = VR. This represents the isoreflectivity curve of maximum reflectivity. Likewise small variations of (VA-VG) = VX optimally should produce a family of curves that closely matches those in Fig. 4. While it is computationally onerous to demonstrate that the circuit shown in general form in Fig. 2 meets this objective, a detailed embodiment illustrated in Fig. 5, which was constructed and tested in a sealed light box, produced the family of curves illustrated in Fig. 7.
In viewing the curves of constant reflectance of the reflectance element 28, or isoreflectivity curves, in Fig. 7, it can be observed that the family of curves have the desired flattened slopes at low ambient levels (below 1.0 lux) and increased slopes at high ambient levels (above 10.0 lux) characteristic of the ideal response illustrated in Fig. 4. While the family of isoreflectivity curves in Fig. 7 diverge from each other at both ends, they are substantially parallel and equally spaced throughout the range of ambient light levels from 0.25 to 10.0 lux. However, it has been discovered that the reflectance of variable reflectance element 28 must approximate the parallel lines of ideal mirror of Fig. 4 only for the approximate range of from 0.25-10.0 lux of ambient light. Below 0.25 lux of ambient, the desired action of the reflectance element is that of a bimodal mirror, which changes between a high reflectance and a low reflectance condition in response to the presence or absence of glare. Subtle variations in reflectance are neither helpful nor noticeable to the driver. Above 10.0 lux of ambient, the driver is relatively immune to glare and would, therefore, likewise not perceive anything but large changes in the reflected glare signal. Therefore, the mirror system in Fig. 5 will approximate the ideal model because the constant reflectance lines are parallel and equally spaced for all values of ambient between 0.25 and 10.0 lux, with a controlled amount of divergence from the ideal for levels of ambient less than 0.25 lux and greater than 10.0 lux.
By reference to Fig 5, mirror system 10′ includes a control circuit 13′ having a modulating bridge network 32, which includes a first leg 33 in parallel with a second leg 35. First leg 33 includes ambient light sensor 12 in parallel with a resistor 39 and in series with a resistor 34. Second leg 35 includes rearward light sensor 14 in series with resistors 36, 37 and 38. Parallel legs 33 and 35 are connected in parallel with each other and through a modulating resistor 40 to a VCC line 42 and through forward-biased diode 44 to signal ground line 46. Operation of such a bridge circuit 32 will be readily understood but is described in detail in our United States Patent Application Serial No. 177,614, filed April 5, 1988 by Keith Winston Molyneux et al. Bridge circuit 32 is based on the recognition that ambient light, which determines the driver's tolerance for glare, is influenced by more than merely the light level sensed by the forward-facing light sensor. Light from the rear of the vehicle, which is reflected by the mirror and other surfaces of the vehicle, adds to the light received from other directions to establish the driver's tolerance for glare. The function of modulating resistor 40 is to cause increases in light levels measured by rearward sensor 14 to increase the level of the ambient light signal. As more light strikes rearward sensor 14, its resistance decreases and the current through bridge arm 35 increases. Because this current also flows through modulating resistor 40, the increase in current in bridge arm 35 increases the voltage drop across modulating resistor 40 which decreases the voltage level of node 41, common to both arms 33, 35. The decrease in the voltage of node 41 reduces the voltage across forward light sensor 12, which appears on ambient light signal line 16′ as an increase in ambient light.
The rearward light signal on line 18′ is buffered by a unity gain amplifier 48 and provided to the inverting terminal 50 of differential-input operational amplifier 20′. A voltage dividing network consisting of resistors 52 and 53 is provided at the output of unity gain amplifier 48 to scale the rearward light signal. The ambient light signal on line 16′ is time-filtered by dynamic asymmetric filter 56. The operation of asymmetric filter 56 is described in our US-A-4,793,690, the disclosure of which is hereby incorporated herein by reference. Filter 56 responds to changes in the signal on line 16′ that represent an increase in the level of ambient light according to a rapid time constant and responds to changes in the signal on line 16′ that represent a decrease in ambient light according to a longer time constant. Thus, filter 56 models the response of the human eye to changes in ambient light. This occular-adapted ambient light signal is provided on a line 58 and is buffered by unity gain amplifier 60. Output 62, from amplifier 60, is connected through a resistor 64 to a network 66 including resistors 68, 69 and 70. Network 66 is connected between a regulated DC voltage line 90 and signal ground line 46 to produce a positive DC offset voltage that biases the output of amplifier 60 on line 72 to a higher level. Line 72 is connected to ground through a resistor 71 and to the noninverting input of amplifier 20′. The values of resistors 68, 69, 70 are selected to provide a positive DC offset for the ambient light signal in order to set the value of the reflectance of the reflective element 28 at 70% when ambient and glare light levels are equal. This represents the maximum reflectivity condition and is selected to coincide with point Z1 in Fig. 3 for equal levels of ambient and glare.
The gain of differential input amplifier 20′ is directly proportional to the resistance of resistor 22′ which is connected between inverting input terminal 50 and output terminal 74. Because amplifier 20′ produces an output which is a product of its gain and the difference between the signals at its input terminals 50, 72 and the value of gain is directly proportional to the resistance value of resistor 22′, the slope of the output of amplifier 20′ can be adjusted so that incremental changes of the drive signal produced by circuit 13 with respect to the difference between the ambient and rear light signals can be matched to the reflectivity vs. drive signal performance characteristics of the reflectance element. In this manner, reflective elements having various reflectance vs. voltage characteristics may be matched to the control circuit by adjusting the resistance value of resistor 22′. If a balanced response is desired from amplifier 20′ then the value of resistor 71 must be adjusted in tandem with resistor 22′. A balanced response is dependent only on the difference between the levels of the input signals irrespective of their absolute levels. However, absolute balance may not be required for all applications and, if not, only resistor 22′ need be modified.
A voltage divider, including resistors 76, 77 between output terminal 74 and signal ground line 46, produce a voltage signal at common junction 78, which is a scaled version of the output of amplifier 20′. The signal on junction 78 is buffered by a unity gain amplifier 80 whose output produced on line 24′ is connected with terminal 26 of variable reflectance element 28. The opposite terminal 30 of variable reflectance element 28 is connected to the output on line 25 of a unity gain amplifier 84 whose noninverting input terminal 86 is maintained at a fixed DC voltage level by connection with a voltage divider, including resistors 88, 89 connected in series between regulated voltage line 90 and signal ground line 46. Amplifier 84 is unity gain because of a direct feedback connection from its output to its inverting input 85. By this arrangement, amplifier 84 produces a constant positive DC voltage on its output terminal 82 established by the ratio of resistance value of resistors 88, 89. Terminal 30 of cell 28 is thus maintained at a constant positive DC offset voltage with respect to signal ground. In the illustrated embodiment, terminal 30 is maintained at a constant 0.6 volts DC but may be set at any value suitable for the cell used.
A transistor 92 is provided with its collector connected with terminal 72 and its emitter connected with signal ground line 46. The base of transistor 92 is connected through a dropping resistor to a terminal 94 which receives a positive voltage whenever the vehicle is placed in reverse gear. The positive voltage to the base of transistor 92, in response to the vehicle being placed in reverse gear, clamps the voltage on line 72 to a low level which forces the variable reflectance element 28 to a condition of maximum reflectivity whenever the vehicle is moving backward. A transistor 96 connected with its collector and emitter across lines 24 and 25, has its base connected through a line 98 to the collector of a transistor 100, whose emitter is connected to VCC line 42 and whose base is connected to a terminal 102 of a mode control switch 104. The wiper 106 of switch 104 is connected to ground such that, when wiper 106 contacts terminal 102, the base of transistor 100 is low, which causes transistor 100 to conduct and provide a positive voltage on line 98. This positive voltage provided to the base of transistor 96, in response to the mode switch being placed in the day-lock mode, causes transistor 96 to conduct to immediately bleed any charge from variable reflectance element 28 to rapidly force it into a maximum reflectivity condition. An opposite terminal 108 of switch 104 is connected to the junction between resistors 36 and 37. Whenever wiper 106 is placed in contact with terminal 108, the voltage on line 18′ is reduced. This has the effect of causing the mirror system 10′ to be forced to a night mode with element 28 having a low reflectance value.
Terminal 110, which is the source of power for mirror 10′, is provided with a positive DC voltage whenever the vehicle is running. A transistor 91, in series between terminal 110 and line 90 and whose base is connected with terminal 102, produces a voltage on line 90, which feeds power to the active circuit components, such as the amplifiers. Line 102 is connected through a resistor 113 to the junction between a resistor 114 and zener diode 116 and is maintained at a constant voltage to, in turn, maintain a constant supply voltage to the circuit. When switch 104 is placed in the day-lock mode, the drop in voltage on line 102 turns off transistor 91 which immediately powers-down the amplifiers to remove any drive signal from being applied to variable reflectance element 28, concurrently with producing a short circuit across the element with transistor 96 as previously explained. A diode 122 provides reverse voltage protection and an MOV 124 protects against voltage surges. Diodes 126 and diode string 128 across lines 24, 25 provide voltage protection to variable reflectance element 28. A bleed resistor 101 dissipates any residual charge from reflectance element 28 when power is removed from terminals 110, 111.
Additional reflectance elements (not shown), such as door-mounted mirrors may be operated as part of mirror system 10′. Such additional reflectance elements are connected with terminals 135, 136. Therefore, the door-mounted mirrors receive the same drive signal as variable reflectance element 28 and are, accordingly, glare-protected.
The output of amplifier 20′ on line 74 and the output of the control circuit on line 24′ are illustrated in Fig. 6 as a function of the voltage difference between the ambient light signal on line 16′ and rearward light signal on line 18′. It can be seen that, when the value of the signals are equal, which corresponds to a desired reflectance value of approximately 70%, the output on line 24′ is approximately two volts. As the glare light level increases with relationship to the ambient light signal level, the voltage on line 24′ decreases in a linear fashion. Because the opposite terminal 30 of element 28 is clamped at positive 0.6 volts DC, the voltage across element 28 will vary between approximately -0.6 volts at low glare, high ambient conditions to +1.5 volts at high glare, low ambient condition. This example is for cells having electrochromic coatings. Other types of cells, such as electrochemichromic, would operate at different voltages.
The ability to provide a negative voltage across variable reflectance element 28 provides rapid and definite bleaching of the cell when high reflectance is desired. The combination of the offset provided to the ambient light signal by offset circuit 21 and the gain established by the resistance value of resistor 22′ causes the system to tend to operate between points Z1 and Z2 on the chart in Fig. 3 during ambient light levels of between 0.25 and 10.0 lux, which, in conjunction with other elements of circuit 13, produces the favourable results illustrated in Fig. 7.
By reference to Fig. 7, it can be observed that between 0.25 and 10.0 lux of ambient light, the constant reflectivity lines are substantially parallel and evenly offset. While the lines diverge slightly below 0.25 lux and above 10.0 lux, the need for following the ideal model diminishes outside of this range, as previously set forth. Within that range, however, for a given ambient level, an increase in glare will cause the voltage level on line 18′ to decrease, which will increase the output signal level of subtracting amplifier 20′ if the glare level is constant. This causes the drive signal applied to the terminals of reflective element 28 to decrease, which increases the reflectance level of the mirror at a time rate that would correspond to the adaptation of the eye to the change in ambient level, which increases the glare tolerance of the driver.
One difficulty experienced primarily in electrochemichromic cells is the tendency of reactant products to migrate toward the terminals of the cell as a result of the DC field established by the drive current and voltage. The effect is not totally reversed when the cell is bleached, resulting in a noticeable band of residual coloration in portions of the cell. In order to overcome this difficulty, the mirror system 10˝ in Fig. 8 reverses the polarity of the drive signal to the variable reflectance element every time the system goes from a bleached to a coloured condition. This is possible because variable reflectance element 28˝ colours in response to the absolute magnitude of the drive signal irrespective of its polarity.
In the embodiment illustrated in Fig. 8, a comparator 141 has a noninverting input connected to output line 24 from amplifier 80 and an inverting input connected to a fixed voltage level V₁. Output 142 of the comparator is provided as an input to a reversing switch 143. Reversing switch 143 includes a pair of input terminals A₁, A₂ connected respectively with output line 24 and signal ground. Reversing switch 143 additionally includes a pair of output terminals B₁, B₂ connected with terminals 26, 30 of element 28. Reversing switch 143 in one state has inputs A₁, A₂ connected with outputs B₁, B₂, respectively, and in an alternate state has inputs A₁, A₂ connected with outputs B₂, B₁, respectively. Reversing switch 143 reverses states when a negative trending pulse is received from comparator 141.
In operation, when the condition of circuit 13˝ causes amplifier 20 to produce an output signal less than V₁, which represents a maximum reflectivity state, the output of comparator 141 switches from a positive to a negative level which causes reversing switch 143 to reverse the interconnectors between input terminals A₁, A₂ and output terminals B₁, B₂. In this manner, the signal applied to the terminals 26, 30 of element 28 will reverse polarity after every time the element is "bleached" to a maximum reflectance condition. Because variable reflectance element 28˝ is of the type that adjusts the reflectivity based on amplitude of the drive signal, regardless of polarity, this reversing of drive signal polarity will tend to reduce the tendency of chemical reaction by-products to accumulate within element 28.
While the mirror system in Fig. 8 reduces the tendency for accumulation of reaction by-products, there is a further necessity to increase the speed of response of the variable reflectance element to changes in the desired reflectance level resulting from changes in the ambient and/or glare light intensities. In order to improve the response of the mirror system 10‴ to a desired bleach condition, or maximum reflectivity, the circuit in Fig. 9 responds to the output on line 24 of amplifier 20 decreasing below a predetermined voltage level V₂, indicative of a maximum reflectivity condition, by momentarily superimposing a negative voltage on the drive signal to cell 28‴.
Referring to mirror system 10‴, illustrated in Fig. 9, a shorting switch 150 around an offset device 23a in circuit 13‴ is opened by the output of a timer 151 for a predetermined period of time in response to output 24 of amplifier 20, producing a desired reflectivity signal on line 24 that is less than V₂, which indicates a desired "bleached", or maximum, reflectivity condition. The offset provided by offset device 23a is selected to provide a significant negative voltage voltage across terminals 28, 30 of reflectance element 28 when switch 150 is open.
In operation, when the level of the output of amplifier 20 decreases to V₂, which is a maximum reflectivity output level, the output change from comparator 141 causes timer 151 to open switch 150 for a predetermined period of time. When switch 150 opens, the signal level across terminals 26, 30 of element 28 goes more negative by the amount of offset provided by device 23a minus the level of V₂. After timer 151 times out, switch 150 closes, which causes the signal level across terminals 26, 30 to rise to the maximum reflectivity signal level V₂. The brief negative signal across terminals 26, 30 causes a raped bleaching of element 28. However, by only applying such negative signal for a brief period of time, such as two seconds, a recolouration of the cell as a result of the negative voltage is avoided.
While the mirror system, illustrated in Fig. 9, is capable of improving significantly the rate at which the variable reflectance element bleaches to a maximum reflectivity condition, it does not per se improve the speed of response for a bleaching to an intermediate reflectivity condition nor does it increase the speed of coloration of the mirror to a lower reflectivity condition. The embodiments illustrated in Figs. 10-12 address the speed of response problem for substantially all changes of the desired reflectivity of the variable reflectance element, including small and large changes and changes in either direction of reflectivity. By reference to Fig. 10, a mirror system 160 includes a circuit 162 which receives inputs from forward light sensor 12 and rearward light sensor 14 and produces an output on line 164, which indicates the desired reflectance condition of variable reflectance element 166. Circuit 162 could correspond to that illustrated in Fig. 5 or could be any system which produces an output signal on line 164 that is responsive to the intensity of light sensed by sensors 12 and 14. A drive circuit 167 receives the desired reflectance signal from line 164 and applies a drive signal on lines 168 and 169 to variable reflectance element 166. Drive circuit 167 additionally receives a constant voltage input V₃ on line 170.
When the desired reflectance signal on line 164 is quiescent, the drive signal on line 168 is equal to the signal on line 164. Likewise, when the signal on line 164 is quiescent, the drive signal on line 169 is equal to the constant signal on line 170. However, when the desired reflectance signal on line 164 changes, the drive circuit 167 temporarily offsets the input signal on one of lines 168 and 169 in order to temporarily offset the input signal applied to variable reflectance element 166. The temporary offset is in the direction of change of the variable reflectance signal. Therefore, if the signal level on line 164 increases, the signal applied to element 166 will be offset in the increased direction for a brief period of time. This is accomplished by producing an offset on line 168. If the level of the desired reflectance signal on line 164 decreases, then a temporary offset tending to decrease the signal applied to element 166 is produced for a brief period of time. This is accomplished in the illustrated embodiment by producing an offset on line 169 for a brief period of time. The length of the offset is chosen to be less than the time required for the reflectance condition of element 166 to approach the new desired reflectance level. Additionally, the input signal to element 166 as increased by the offset may temporarily exceed the safe operating level of the variable reflectance. However, because of the temporary nature of the offset, damage to element 166 is avoided.
Operation of drive circuit 167 is illustrated by reference to Fig. 11. Line 164 is provided to the non-inverting input of an operational amplifier 172. Amplifier 172 produces an output on lid 168 as a drive signal to variable reflectance element 166. A variable feedback element 174 is connected between line 168 and the inverting input 176 to amplifier 172. Constant signal V₃ is provided on line 170 to the non-inverting input of an operational amplifier 178. The output of amplifier 178 is provided on line 169 as an input signal to element 166. A variable feedback element 180 is connected between output line 169 and the inverting input 182 of amplifier 178. Variable feedback element 180 additionally receives the desired reflectance level signal from line 164 at an input 184.
Variable feedback elements 174 and 180 are selected in order to cause amplifiers 172 and 178 to normally operate as unity gain amplifiers. Although a short-circuit feedback is typically required for providing a unity gain amplifier, the impedance of amplifiers 172 and 178 is sufficient to operate as unity gain even with a substantial impedance in variable feedback elements 174 and 178. As along as amplifiers 172 and 178 are operating as unity gain, the drive signal on line 168 is at the same level as the desired reflectance signal on line 164 and the drive signal on line 169 is at the same level as constant signal V₃ on line 170. When the signal on line 164 increases, the output on line 168 increases. Variable feedback element 174 is sensitive to the level of signal on line 168 and responds by temporarily increasing the gain of amplifier 172. The increase in gain is temporary and causes the drive signal on line 168 to be amplified with respect to the desired reflectance signal on line 164 which further increases the signal on line 168. The increased gain from variable feedback device 174 immediately begins to decrease to unity gain. Once variable feedback device 174 returns amplifier 172 to unity gain, the signal on line 168 is the same as the desired reflectance signal on line 164. An increase in the desired reflectance signal does not produce a significant effect on the output 169 of amplifier 178 which cannot drop below signal ground. Therefore, the drive signal on line 169 remains at the level of V₃.
When the desired reflectance signal on line 164 decreases, the change in the input 184 to variable feedback device 180 temporarily increases the gain of amplifier 178. This increases the signal on line 169 because the change is coupled to inverting input 182 and the difference between the inputs on lines 170, 182 is multiplied by the gain of amplifier 178. With the drive signal on line 169 temporarily increased, the effect of the decreasing desired reflectance signal on line 168 is augmented by a negative offset induced by the increase on the signal on line 169. Thus, it is seen that the drive signal applied to element 166 receives a temporary offset in the direction of movement of the desired reflectance signal whether the direction of movement is in the direction of the desired reflectance signal is in the direction increasing the desired reflectance signal, which decreases the reflectance of element 166 or decreasing in the desired reflectance signal on line 164 which increases the reflectance of the element 166.
A detailed embodiment of the circuit illustrated in Fig. 11 is shown in Fig. 12. Unmarked elements are the same as those illustrated in Fig. 5 and, as explained with respect to Fig. 5, the output of differential input operational amplifier 20 on line 74 is a function of the rearward light signal sensed by sensor 14 and the intensity of light in a direction other than rearward of the vehicle sensed by sensor 12. Output 74 is scaled by resistor 76 and 77 in order to produce a signal on line 164, which represents the desired reflectance level of the mirror. Line 164 is connected with the non-inverting input of operational amplifier 172 whose output produced on line 168 is connected through a feedback resistor 186 to the inverting input 176 of the amplifier. Line 176 is additionally connected through a resistor 178 and capacitor 180 to signal ground. Resistor 186 is selected to have a resistance value that will be in the range sufficient to cause amplifier 172 to be unity gain. When the desired reflectance signal on line 164 increases, the resulting increase in the output on line 168 will tend to increase the voltage on inverting input 176. However, because the voltage across capacitor 180 cannot instantaneously change, no voltage increase will be experienced on line 176. The difference in voltage between line 168 and 176 increases the gain of amplifier 172. As capacitor 180 charges, the voltage on line 176 will approach that of line 168. As it does, the gain of amplifier 172 returns to essentially unity. Therefore, for increases in the voltage on line 164, the gain of amplifier 172 temporarily increases to a value equal to the sum of the resistances of resistors 178 and 186 divided by the resistance of resistor 178. The temporary increase in gain is determined by the time constant of the resistance of resistors 178 and 186, after which the gain of amplifier 172 returns to unity.
A pair of resistors 192, 194 connected in series with constant voltage line 90, establish a constant voltage level on line 170 which is connected with the non-inverting input of amplifier 178. In the illustrated embodiment, the voltage on line 170 is selected at 0.2 volts. However, this voltage is dependent upon the type of electrochromic cell used for element 166. Desired reflectance signal line 164 is connected through a resistor 196 and capacitor 198 to inverting input line 182 of amplifier 178. A feedback resistor 200 is connected between line 169, which receives the output from amplifier 178, and input line 182. As previously set forth, amplifier 178 amplifies the constant voltage signal on its input line 170. When the desired reflectance signal level on line 164 is quiescent, amplifier 178 amplifies the constant level signal on line 170 by a unity gain to provide a positive offset to one terminal of element 166. When the level of the signal on line 164 decreases, the input on line 182 to amplifier 178 is momentarily decreased, which increases the gain of amplifier 178 and thus produces a higher signal output on line 169. As the voltage across capacitor 198 charges, the voltage on line 182 will increase to return the gain of amplifier 168 to unity, which will bring the voltage on line 169 back to the level of the constant voltage on line 170. Therefore, mirror system 160 responds to decreases in the voltage level on desired reflectance signal line 164 by momentarily increasing the voltage on line 169 which has the effect of adding a negative offset to the decreasing desired reflectance drive signal applied to element 166. This negative offset enhances the action of the decreasing voltage across element 166 in increasing the speed of colouration of the element. In this embodiment, an indication LED 204 is actuated from output 74 of amplifier 20 through a transistor 202 biased as an amplifier by resistors 206 and 208. Thus, LED 204 has a variable intensity to indicate the reflectivity level of element 166.
While the invention has been illustrated with sensors 12, 14 arranged in a bridge circuit with a modulating resistor 40, other arrangements are possible. For example, the rear and ambient light signals could be provided by independent forward and rear sensors which do not account for the influence of light from rearward of the vehicle on the ambient light signal. A drive circuit according to the invention will therefore accommodate the design goal of the designer while approximating the ideal response of a continuously variable reflectance element. Light sensors that do not have the characteristics of cadmium sulphite photo resistor sensors could be utilized by amplifying their signals with specially configured nonlinear amplifiers, such as logarithmic amplifiers.
The invention may be defined in various ways certain of which have initially been selected in the claims. Other approaches to the invention which may be made are set out in the following clauses which are included for disclosure purposes and which are not at present claimed but which may be included in claims at a later stage of prosecution.
means for providing said output signal to one of said input terminals such that the transmittance value of said reflective element is a function of said output signal.
Clause 2. The automatic rearview mirror system of clause 1 further including gain control means for establishing a gain value for said amplifier such that said output signal is a function of the multiplication product of said gain value and said difference between said ambient light signal and said rear light signal.
Clause 3. The automatic rearview mirror system of clause 2 wherein said gain value is selected as a function of said performance characteristic of said variable light attenuating means.
Clause 4. The automatic rearview mirror system of clause 3 wherein the relationship between said transmittance value and said input signal includes a first value of said relationship within a first range of values of said input signal and a second different value of said relationship within a second range of values of said input signal and wherein said mirror system further includes first offset means for producing a first offset signal and applying said first offset signal to said ambient light signal in order to cause said input signal to operate substantially only within one of said range of values.
Clause 5. The automatic rearview mirror system of any of clauses 1 to 4 wherein the relationship between said transmittance value and said input signal includes a first value of said relationship within a first range of values of said input signal and at a second rate within a second range of values of said input signal and a second different value of said relationship within a second range of values of said input signal and wherein said mirror system further includes first offset means for producing a first offset signal and applying said first offset signal to said ambient light signal in order to cause said output signal to operate substantially only within one of said range of values.
Clause 6. The automatic rearview mirror system of clause 5 further including second offset means for producing a second offset signal and applying said second offset signal to the other one of said input terminals in order to adjust the value of the signal applied to said input terminals as a function of said output signal.
Clause 7. The automatic rearview mirror system of any of clauses 1 to 6 in which said ambient light sensing means includes a first sensor having a parameter that varies in response to the intensity of light received by said ambient light sensing means, said rear light sensing means includes a second sensor having a parameter that varies in response to the intensity of light received by said rear light sensing means and said mirror system further including a modulating resistor, wherein said first and second sensors are connected in parallel with one another and in series with said modulating resistor between a pair of supply voltage terminals, said ambient light signal being a function of said parameter of said first sensor and said rear light signal being a function of said parameter of said second sensor such that a change in said parameter of said second sensor will modify said ambient and said rear light signals.
Clause 8. The automatic rearview mirror system of clause 7 further including time-filtering means for time-filtering said ambient light signal, said time-filtering means providing faster time-filtering of the signal during periods of increasing ambient light than during periods of decreasing ambient light.
biasing means for adjusting the relationship between the input signal applied to said input terminals and the value of said ambient and rear light signals. Clause 10. The automatic rearview mirror system of clause 9 in which said biasing means includes means for applying a predetermined signal level to one of said ambient and rear light signals.
Clause 11. The automatic rearview mirror system of clause 10 in which said biasing means includes means for applying another predetermined signal level to one of said terminals of said reflective element.
Clause 12. The automatic rearview mirror system of clause 11 in which said biasing means includes means for applying a predetermined signal level to one of said terminals of said reflective element.
Clause 13. The automatic rearview mirror system of any of clauses 9 to 12 in which said control means includes a difference amplifier having an inverting input and a noninverting input and wherein said ambient light signal is applied to said noninverting input and said rear light signal is applied to said inverting input and further wherein said biasing means includes means for adding a predetermined offset level to the ambient light signal applied to said noninverting input.
Clause 14. The automatic rearview mirror system of clause 13 wherein said output signal is applied to a first one of said terminals and said biasing means further includes means for applying another predetermined signal level to a second one of said terminals.
Clause 15. The automatic rearview mirror system of any of clauses 9 to 12 wherein said control circuit means includes a difference amplifier having an inverting input connected to receive said rear light signal, a noninverting input connected to receive said ambient light signal, an output and a gain establishing means for establishing a gain value such that a signal on said output is equal to the product of the gain value and the difference between said ambient light signal and said rear light signal, and wherein said gain establishing means establishes said gain value at a value that will cause said signal on said output to change with respect to the difference between said ambient and rear light signals according to a relationship that matches a performance characteristic of said reflectance element.
control circuit means responsive to said ambient light signal and said rear light signal for producing output signal and providing said output signal to said terminals in order to determine the value of transmittance of said attenuating means, said control circuit means including a difference amplifier having an inverting input connected to receive said rear light signal, a noninverting input connected to receive said ambient light signal, a gain establishing means for establishing a gain value such that said output signal is equal to the product of the gain value and the difference between said ambient light signal and said rear light signal, and wherein said gain establishing means establishes said gain value at a value that will cause said output signal to change with respect to the difference between said ambient and rear light signals in a manner that substantially matches said performance characteristic of said reflective element.
Clause 17. The automatic rearview mirror of clause 16 wherein the relationship between said transmittance value and an input signal applied to said terminal includes a first value of said relationship within a first range of values of said input signal and a second different value of said relationship within a second range of values of said input signal and said mirror system further includes biasing means for causing said output signal to vary substantially only within one of said first and second ranges.
Clause 18. The automatic rearview mirror of clause 17 in which said biasing means includes means for applying a predetermined offset level to one of said ambient and rear light signals and, possibly, means includes means for applying another predetermined offset level to one of said terminals of said reflective element.
Clause 19. The automatic rearview mirror of any of clauses 16 to 18 in which said rear light sensor is positioned such that said rear light signal is independent of the transmittance value of said light attenuating means.
drive means for applying an input signal to said reflective element as a function of said indication, said drive means including means for temporarily offsetting said input signal from a value of said input signal that corresponds to the desired reflectance condition of said reflective element to increase the rate of change of said reflectance condition of the reflectance element.
Clause 21. The automatic rearview mirror system of clause 20 wherein said input signal is temporarily offset by said drive means in the direction of change in said indication.
Clause 22. The automatic rearview mirror system of clause 20 or clause 21 further including means responsive to said indication having a value representing a maximum reflective condition of said reflective element for altering the polarity of said input signal applied to said reflective element.
Clause 23. The automatic rearview mirror system of any of clauses 20 to 22 wherein said mirror system is adapted to operating between a maximum reflectance mode in which light incident the reflectance element is substantially unattenuated and a reduced reflectance mode in which light incident the reflectance element is significantly attenuated and wherein said circuit means is adapted to producing a first indication when said maximum reflectance mode is desired and a second indication when said reflectance mode is desired and further wherein said input signal is temporarily offset by said drive means beyond a value of said input signal that corresponds to said first indication in response to said first indication and is temporarily offset by said drive means beyond a value of said input signal that corresponds to said second indication in response to said second indication.
Clause 24. The automatic rearview mirror system of clause 23 wherein said reflective element is capable of withstanding a constant predetermined level of said input signal and wherein said input signal is temporarily offset beyond said predetermined level by said input means.
Clause 25. The automatic rearview mirror system of any of clauses 20 to 22 wherein the reflective condition of said reflective element is variable to a multiplicity of reflective states and wherein said indication is essentially continuously variable and further wherein said input signal is temporarily offset by said drive means in the direction of change in said indication.
Clause 26. The automatic review mirror system of clause 25 wherein said reflective element is capable of withstanding a constant predetermined level of said input signal and wherein said input signal is temporarily offset beyond said predetermined level by said input means.
Clause 27. The automatic rearview mirror system of clause 25 or clause 26 wherein said indication is substantially independent of the reflectance condition of said reflective element.
Clause 28. The automatic rearview mirror system of clause 27 wherein said circuit means produces said indication as a function of the difference between said ambient light signal and said rear light signal.
Clause 29. The automatic rearview mirror system of clause 28 wherein said circuit means includes time-filtering means for time-filtering said ambient light signal, said time-filtering means providing faster time-filtering of the ambient signal during periods of increasing ambient light, than during periods of decreasing ambient light.
drive means responsive to said desired reflectance signal for producing an input signal applied to said reflective element, said drive means being responsive to changes in said desired reflectance signal to modify the relationship between said desired reflectance signal and said input signal applied to said reflective element.
Clause 31. The automatic rearview mirror system of clause 30 wherein said drive means includes amplifier means for amplifying said desired reflectance signal by a gain of said amplifying means to produce said input signal applied to said reflective element and including means for modifying said gain in response to changes in said indication.
Clause 32. The automatic rearview mirror system of clause 31 wherein said modifying means temporarily increases said gain in response to changes in said desired reflectance signal.
Clause 33. The automatic rearview mirror system of any of clauses 30 to 32 wherein said circuit means produces said desired reflectance signal as a function of the difference between said ambient light signal and said rear light signal and wherein said desired reflectance signal is substantially independent of the reflectance condition of said reflective element.
Clause 34. The automatic rearview mirror system of clause 33 wherein said circuit means includes time-filtering means for time-filtering said ambient light signal, said time-filter means providing faster time-filtering of the ambient signal during periods of increasing ambient light, than during periods of decreasing ambient light.
Clause 35. The automatic rearview mirror system of any of clauses 30 to 34 wherein said reflective condition of said reflective element is variable to a multiplicity of reflective states and wherein said desired reflectance signal is essentially continuously variable and further wherein said input signal is temporarily offset by said drive means, in the direction of change in said indication.
drive means responsive to said output signal for producing first and second input signals applied to said terminals, said drive means being responsive to changes in said desired reflectance signal to temporarily modify the relationship between said desired reflectance signal and said input signals.
Clause 37. The automatic rearview mirror system of clause 36 wherein said drive means includes first amplifying means for amplifying said desired reflectance signal by a first gain to produce a first input signal applied to one of said input terminals and first modifying means for modifying said first gain in response to changes in said desired reflectance signal.
Clause 38. The automatic rearview mirror system of clause 37 wherein said drive means further includes means for producing a constant signal, second amplifying means for amplifying said constant signal by a second gain to produce a second input signal applied to the other one of said input terminals and second modifying means for modifying said second gain in response to changes in said desired reflectance signal.
Clause 39. The automatic rearview mirror system of clause 38 wherein said first amplifying means includes a first amplifier having first and second inputs and a first output port from which a first output signal is produced and wherein said first gain is determined by a first feedback means between said first output port and said first input for feeding a portion of said first output signal to said first input, said desired reflectance signal being connected with said second input, and further wherein said first modifying means includes a resistance-capacitance network connected with said feedback means.
Clause 40. The automatic rearview mirror system of clause 38 or clause 39 wherein said second amplifying means includes a second amplifier having third and fourth inputs and a second output port from which a second output signal is produced and wherein said second gain is determined by a second feedback means between said second output port and said third input for feeding a portion of said second output signal to said third input, said constant signal being connected with said fourth input, and further wherein said second modifying means includes a second resistance-capacitance network connected with said second feedback means, said desired reflectance signal being connected with said second resistance-capacitance network.
Clause 41. The automatic rearview mirror system of any of clauses 37 to 40 wherein said first amplifying means includes a first amplifier having first and second inputs and a first output port from which a first output signal is produced and wherein said first gain is determined by a first feedback means between said first output port and said first input for feeding a portion of said first output signal to said first input, said desired reflectance signal being connected with said second input, and further wherein said first modifying means includes a resistance-capacitance network connected with said feedback means.
1. An automatic rearview mirror system (10,10′) for a vehicle comprising: a reflective element having a reflectance condition that varies as a function of an input signal applied to said element, the relationship between said reflectance condition and said input signal being defined by a performance characteristic of said reflective element; ambient light signal generating means (12) for producing an ambient light signal indicative of the ambient light; rearward light signal generating means (14) for producing a rearward light signal indicative of light rear of the vehicle; and control means (13) responsive to said rear and ambient light sensing means for producing an output signal and applying said output signal to said reflective element, wherein said output signal is a function of the difference between said ambient light signal and said rearward light signal and wherein said output signal is substantially independent of the reflectance condition of said reflective element.
2. An automatic rearview mirror system according to claim 1 wherein said control means further includes gain determining means for establishing a gain value and wherein said output signal is a function of the product of said gain value and said difference between said ambient light signal and said rearward light signal.
3. An automatic rearview mirror system according to claim 2 wherein said gain determining means establishes said gain value as a function of said performance characteristic of said reflective element.
4. An automatic rearview mirror system in according to any of claims 1 to 3 wherein the relationship between said reflectance condition and said input signal includes a first value for said relationship within a first range of values of said input signal applied to said reflective element and a different value of said relationship within a second range of values of said input signal and wherein said control means includes first offset means for producing a first offset signal and for combining said first offset signal with said ambient light signal in order to cause said input signal to operate within one said range of values.
5. An automatic rearview mirror system according to claim 4 further including second offset means for producing a second offset signal and for applying said second offset signal to said reflective element in order to adjust the value of the input signal applied to said reflective element as a function of said output signal.
6. An automatic rearview mirror system according to claim 1 further including offset means for producing an offset signal and for applying said offset signal to said reflective element in order to adjust the value of the input signal applied to said reflective element as a function of said output signal.
7. An automatic rearview mirror system according to any of claims 1 to 6 in which said ambient light signal generating means includes forward light sensing means for sensing light in a direction other than rearward of the mirror and means for modifying the output of said forward light sensing means to produce a modified forward light signal that is a function of the level of said rearward light signal.
8. An automatic rearview mirror system according to claim 7 where in said control means includes time-filtering means for time-filtering said modified forward light signal, said time-filter means providing faster time-filtering of the modified forward light signal during periods of increasing ambient light, than during periods of decreasing ambient light.
9. An automatic rearview mirror system according to any of claims 1 to 8 wherein the reflective element comprises variable light attenuating means for attenuating a portion of light directed into the reflective element as a function of the light transmittance value of said attenuating means, the transmittance value varying as a function of the input signal.
10. An automatic rearview mirror system according to any of claims 1 to 9 in which the control means includes difference amplifier means connected with said ambient and rearward light signal generating means for producing the output signal.
11. An automatic rearview mirror system for a vehicle according to claim 1 in which the control means includes a difference amplifier having an inverting input connected to receive said rearward light signal, a noninverting input connected to receive said ambient light signal, a gain establishing means for establishing a gain value such that said output signal is equal to the product of the gain value and the difference between said ambient light signal and said rearward light signal, and wherein said gain establishing means establishes said gain value at a value that will cause said output signal to change with respect to the difference between said ambient and rearward light signals in a manner that substantially matches said performance characteristic of said reflective element.
12. An automatic rearview mirror according to claim 11 in which the relationship between said transmittance value and an input signal applied to said element includes a first value of said relationship within a first range of values of said input signal and a second different value of said relationship within a second range of values of said input signal and said mirror system further includes biasing means for causing said output signal to vary substantially only within one of said first and second ranges.
13. An automatic rearview mirror according to claim 12 in which said biasing means includes means for applying a predetermined offset level to one of said ambient and rear light signals.
14. An automatic rearview mirror according to claim 13 in which said biasing means includes means for applying another predetermined offset level to one of said terminals of said reflective element.
15. An automatic rearview mirror according to any of claims 1 to 14 in which said rearward light sensor is positioned such that said rearward light signal is independent of the reflectance condition of said reflective element.
16. An automatic rearview mirror system according to claim 1 in which the control means produces an indication of the desired reflectance condition of said reflective element, and includes drive means for applying as the input signal to said reflective element a signal which is a function of said indication, said drive means including means for temporarily offsetting said input signal from a value of said input signal that corresponds to the desired reflectance condition of said reflective element to increase the rate of change of said reflectance condition of the reflectance element.
17. An automatic rearview mirror system according to claim 16 wherein said input signal is temporarily offset by said drive means in the direction of change in said indication.
18. An automatic rearview mirror system according to claim 16 or claim 17 further including means responsive to said indication having a value representing a maximum reflective condition of said reflective element for altering the polarity of said input signal applied to said reflective element.
19. An automatic rearview mirror system according to claim 16 or claim 17 or claim 18 wherein said mirror system is adapted to operate between a maximum reflectance mode in which light incident the reflectance element is substantially unattenuated and a reduced reflectance mode in which light incident the reflectance element is significantly attenuated and wherein said circuit means is adapted to producing a first indication when said maximum reflectance mode is desired and a second indication when said reduced reflectance mode is desired and further wherein said input signal is temporarily offset by said drive means beyond a value of said input signal that corresponds to said first indication in response to said first indication and is temporarily offset by said drive means beyond a value of said input signal that corresponds to said second indication in response to said second indication.
20. An automatic rearview mirror system according to claim 19 wherein said reflective element is capable of withstanding a constant predetermined level of said input signal and wherein said input signal is temporarily offset beyond said predetermined level by said input means.
21. An automatic rearview mirror system according to claim 16 or claim 17 or claim 18 wherein the reflective condition of said reflective element is variable to a multiplicity of reflective states and wherein said indication is essentially continuously variable and further wherein said input signal is temporarily offset by said drive means in the direction of change in said indication.
22. An automatic rearview mirror system according to claim 21 wherein said reflective element is capable of withstanding a constant predetermined level of said input signal and wherein said input signal is temporarily offset beyond said predetermined level by said input means.
23. An automatic rearview mirror system for a vehicle comprising: a reflective element having a reflectance condition that varies as a function of an input signal applied to said reflective element; ambient signal generating means for producing an ambient signal indicative of the ambient light; rearward light signal generating means for producing a rear light signal indicative of light rear of the vehicle; circuit means responsive to said ambient and rearward light signals for producing a desired reflectance signal indicative of the desired reflectance condition of said reflective element; and drive means responsive to said desired reflectance signal for producing an input signal applied to said reflective element, said drive means being responsive to changes in said desired reflectance signal to modify the relationship between said desired reflectance signal and said input signal applied to said reflective element.
24. An automatic rearview mirror system according to claim 23 wherein said drive means includes amplifier means for amplifying said desired reflectance signal by a gain of said amplifying means to produce said input signal applied to said reflective element and including means for modifying said gain in response to changes in said indication.
25. An automatic rearview mirror system according to claim 24 wherein said modifying means temporarily increases said gain in response to changes in said desired reflectance signal.
26. An automatic rearview mirror system according to any of claims 23 to 25 wherein said circuit means produces said desired reflectance signal as a function of the difference between said ambient light signal and said rearward light signal and wherein said desired reflectance signal is substantially independent of the reflectance condition of said reflective element.
27. An automatic rearview mirror system according to claim 26 wherein said circuit means includes time-filtering means for time-filtering said ambient light signal, said time-filter means providing faster time-filtering of the ambient signal during periods of increasing ambient light, than during periods of decreasing ambient light.
28. An automatic rearview mirror system according to any of claims 23 to 27 wherein said reflective condition of said reflective element is variable to a multiplicity of reflective states and wherein said desired reflectance signal is essentially continuously variable and further wherein said input signal is temporarily offset by said drive means in the direction of change in said indication.
FR2701905A1 (en) * 1993-02-25 1994-09-02 Glaverbel Vehicle mirror and adapter for introduction.
BE1008910A5 (en) * 1993-02-25 1996-10-01 Glaverbel Vehicle and mirror adapter dito.
ES2112102A1 (en) * 1993-02-25 1998-03-16 Glaverbel rearview mirror assembly for a vehicle and adapter for that set.


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Macular Pigment Density Testing
September 1, 2010 September 1, 2010 / jwarrenod	/ 2 Comments
Macular Degeneration is a disease that can wreak havoc on the vision and quality of life for many patients. There have been many well designed studies performed to study this disease, its treatment, its causes and its prevention. One of the best designed and executed studies to date was the Age Related Eye Disease Study (AREDS for short). This study found that patients who were at increased risk to develop MD could reduce this risk by approximately 25% by taking a nutritional supplement that contained; Vitamins A, E and C and the minerals Zinc and Copper. These patients could not achieve the same risk reduction by diet alone. That last sentence is critical. It means that naturally occurring vitamins and minerals could not equal the protective value of a readily available nutritional supplement.
Other studies looking at the protective properties of nutrients/pigments such as Lutein have found that patients who have a low level of Lutein, Zeaxanthin and Meso-Zeaxanthin in their macula are roughly TWICE as likely to develop MD as patients with average or high levels of these nutrients. Until recently, it was difficult to recommend specific supplements for these nutrients, because patients with normal and high levels of them in their macula would not benefit from them, it is only the patients with low levels who will benefit from them.
We have technology in the office which measures the level of these three critical pigments in a quick, non-invasive and easy to perform test. This technology is called the "MacuScope". By evaluating patients for the density of these pigments we can detect patients who are at elevated risk for MD and make scientifically guided supplement recommendations. The hope is to reduce my patients' risk for MD, before the disease shows up and robs them of vision.
I feel so strongly about this testing and its value to my patients that we include the testing in our comprehensive eye examinations at no additional charge.
Nice Video On Daily Disposable Lenses
September 1, 2010 / jwarrenod	/ Leave a comment
Here's a video that talks about the benefits of Daily Disposable contact lenses (lenses that are worn once and discarded). In just a few minutes it explains things better than I could in a page and a half of written information!


The Vegas Golden Knights have teamed up with Zappos to support the official VGK Sled Hockey Team. Zappos will be the presenting sponsor of the team and will fund the team's ice time, equipment, travel and more!
"We believe in encouraging change and inclusivity - whether that's with shoes and clothing, or sports. Everyone should have the opportunity to do what they love and purse their passions," said Steven Bautista, head of charitable giving at Zappos. With outside funding helping them cover vital costs, the VGK Sled Hockey Team can start competing in tournaments against other sled hockey clubs.
The team practiced in front of media and fans at City National Arena on Monday and took the T-Mobile Arena ice Wednesday night for a shootout during the first intermission of the Golden Knights game vs. Anaheim.
The sled hockey team showed off their VGK sweaters with a new Zappos patch on the front as they hit the ice at T-Mobile arena.
Each player got the opportunity to shoot on goal, and on such as large stage, it made for a memory they will never forget. The team will take off for tournaments in Anaheim in January and Chicago in February as they will play other NHL sanctioned sled hockey teams.


text:
import d3 from 'd3';
import _ from 'lodash';
import VislibLibErrorHandlerProvider from 'ui/vislib/lib/_error_handler';
import VislibComponentsTooltipProvider from 'ui/vislib/components/tooltip';
export default function ChartTitleFactory(Private) {

  const ErrorHandler = Private(VislibLibErrorHandlerProvider);
  const Tooltip = Private(VislibComponentsTooltipProvider);

  /**
   * Appends chart titles to the visualization
   *
   * @class ChartTitle
   * @constructor
   * @param el {HTMLElement} Reference to DOM element
   */
  class ChartTitle extends ErrorHandler {
    constructor(el) {
      super();
      this.el = el;
      this.tooltip = new Tooltip('chart-title', el, function (d) {
        return '<p>' + _.escape(d.label) + '</p>';
      });
    }

    /**
     * Renders chart titles
     *
     * @method render
     * @returns {D3.Selection|D3.Transition.Transition} DOM element with chart titles
     */
    render() {
      const el = d3.select(this.el).select('.chart-title').node();
      const width = el ? el.clientWidth : 0;
      const height = el ? el.clientHeight : 0;

      return d3.select(this.el).selectAll('.chart-title').call(this.draw(width, height));
    };

    /**
     * Truncates chart title text
     *
     * @method truncate
     * @param size {Number} Height or width of the HTML Element
     * @returns {Function} Truncates text
     */
    truncate(size) {
      const self = this;

      return function (selection) {
        selection.each(function () {
          const text = d3.select(this);
          const n = text[0].length;
          const maxWidth = size / n * 0.9;
          const length = this.getComputedTextLength();
          let str;
          let avg;
          let end;

          if (length > maxWidth) {
            str = text.text();
            avg = length / str.length;
            end = Math.floor(maxWidth / avg) - 5;
            str = str.substr(0, end) + '...';
            self.addMouseEvents(text);

            return text.text(str);
          }

          return text.text();
        });
      };
    };

    /**
     * Adds tooltip events on truncated chart titles
     *
     * @method addMouseEvents
     * @param target {HTMLElement} DOM element to attach event listeners
     * @returns {*} DOM element with event listeners attached
     */
    addMouseEvents(target) {
      if (this.tooltip) {
        return target.call(this.tooltip.render());
      }
    };

    /**
     * Appends chart titles to the visualization
     *
     * @method draw
     * @returns {Function} Appends chart titles to a D3 selection
     */
    draw(width, height) {
      const self = this;

      return function (selection) {
        selection.each(function () {
          const div = d3.select(this);
          const dataType = this.parentNode.__data__.rows ? 'rows' : 'columns';
          const size = dataType === 'rows' ? height : width;
          const txtHtOffset = 11;

          self.validateWidthandHeight(width, height);

          div.append('svg')
          .attr('width', width)
          .attr('height', height)
          .append('text')
          .attr('transform', function () {
            if (dataType === 'rows') {
              return 'translate(' + txtHtOffset + ',' + height / 2 + ')rotate(270)';
            }
            return 'translate(' + width / 2 + ',' + txtHtOffset + ')';
          })
          .attr('text-anchor', 'middle')
          .text(function (d) {
            return d.label;
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          // truncate long chart titles
          div.selectAll('text')
            .call(self.truncate(size));
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  return ChartTitle;
};

redpajama_set_name: RedPajamaGithub


text:
Sports Books > Motor sports
Sports Books > Sporting events & management > History of sport
The Ghosts of NASCAR: The Harlan Boys and the First Daytona 500 (Paperback)
John Havick (author)
Who won the first Daytona 500? Fans still debate whether it was midwestern champion Johnny Beauchamp, declared the victor at the finish line, or longtime NASCAR driver Lee Petty, declared the official winner a few days after the race. The Ghosts of NASCAR puts the controversial finish under a microscope. Author John Havick interviewed scores of people, analysed film of the race, and pored over newspaper accounts of the event. He uses this information and his deep knowledge of the sport as it worked then to determine what probably happened. But he also tells a much bigger story: the story of how Johnny Beauchamp-and his Harlan, Iowa, compatriots, mechanic Dale Swanson and driver Tiny Lund-ended up in Florida driving in the 1959 Daytona race.
The Ghosts of NASCAR details how the Harlan Boys turned to racing cars to have fun and to escape the limited opportunities for poor boys in rural southwestern Iowa. As auto racing became more popular and better organised in the 1950s, Swanson, Lund, and Beauchamp battled dozens of rivals and came to dominate the sport in the Midwest. By the later part of the decade, the three men were ready to take on the competition in the South's growing NASCAR circuit. One of the top mechanics of the day, Swanson literally wrote the book on race cars at Chevrolet's clandestine racing shop in Atlanta, Georgia, while Beauchamp and Lund proved themselves worthy competitors. It all came to a head on the brand-new Daytona track in 1959.
The Harlan Boys' long careers and midwestern racing in general have largely faded from memory. The Ghosts of NASCAR recaptures it all: how they negotiated the corners on dirt tracks and passed or spun out their opponents; how officials tore down cars after races to make sure they conformed to track rules; the mix of violence and camaraderie among fierce competitors; and the struggles to organise and regulate the sport. One of very few accounts of 1950s midwestern stock car racing, The Ghosts of NASCAR is told by a man who was there during the sport's earliest days.
Publisher: University of Iowa Press
"Dale Swanson was a top race mechanic, careful and creative. Tiny Lund was a good, ferocious competitor, particularly on dirt tracks, and Johnny Beauchamp in fewer than thirty races proved he could race and win against the top NASCAR drivers. This book describes how these three learned to compete on midwestern tracks. . . . It is a story not to be missed."--Rex White, 1960 NASCAR Grand National Champion
"A detailed account of stock car racing's overlooked pre-TV days, a simpler era when a big-hearted, lead-footed, small-town midwestern boy could reach NASCAR's top tiers. This is more than an investigation of the controversial first Daytona 500. It's the story of the sport's coming of age."--Neal Thompson, author, Driving with the Devil: Southern Moonshine, Detroit Wheels, and the Birth of NASCAR
"John Havick has written an important, informative account of the early days of racing in the Midwest. He focuses on the life and times of Iowan Johnny Beauchamp, the Ghost of Playland Park, the declared victor of the very first Daytona 500--until NASCAR czar Bill France and racing legend Lee Petty conspired to cheat him out of his victory. The Ghosts of NASCAR is a winner."--Peter Golenbock, author, American Zoom, Last Lap, and NASCAR Confidential
100 Years of the Isle of Man TT
Michael Cannell
Ron Haslam
British Motorcycle Racing Circuits Since 1907.
Mick Walker
Formula One on This Day
Rob Burnett
That Near Death Thing
Rick Broadbent
How To Drive: The Ultimate Guide, from the Man Who Was the Stig
Guy Martin: My Autobiography
Top Gear Supercars
Steve Parrish
Lewis Hamilton: My Story
Graham Robson
What If I Had Never Tried It
365 Days of Motoring
Nigel Freestone


text:
Liquor to price 25% extra in Andhra Pradesh
By admin Last updated May 4, 2020
The State government is going to allow reopening of liquor shops in all zones except containment areas from Monday, subject to social distancing and other guidelines laid down by the Central government, besides reducing their number significantly.
This apart, the government has ordered that the prices of liquor be jacked up by 25% as a step towards implementing total prohibition.
These decisions were taken at a high-level meeting chaired by Chief Minister Y.S. Jagan Mohan Reddy on Sunday.
'Social distancing must'
Officials told the Chief Minister that liquor shops were opened in various States as the Central government found it appropriate to allow them to resume business, but stressed the need to avoid rush at the shops and maintenance of safe distance by the customers.
"Since the government has committed itself to total prohibition, incremental steps need to be taken for curbing the social evil," the Chief Minister said.
As belt shops had been closed, focus should now be laid on weaning alcoholics away from the habit, he said. "One way to do that is to steadily increasing the prices," the Chief Minister said. The number of liquor shops had already been reduced from 4,380 to 3,500, he added. Another step would be to regulate the sales timings, he added.
Making it clear that only migrant workers were being allowed into the State as per the Central government guidelines, Mr. Jagan Mohan Reddy advised others to stay where they were instead of reaching the borders and putting themselves to trouble.
He said the government was supposed to send those coming from other States to quarantine, but providing them facilities proved to be difficult as thousands of workers were heading home.
"Those who are not migrant labourers have, therefore, been advised to stay at their current location till the extended lockdown period ends. Migrant workers being sent to their States by special trains should be taken care of properly," he said.
Further, the Chief Minister ordered that steps be taken on a war-footing to set up quarantine facilities at the ward and village secretariats.
UAE books 3 extra Indians for spreading hate on-line
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Time for a loose hand
Productivity shouldn't be a force


text:
Saropogon is a genus of robber flies (insects in the family Asilidae). There are at least 120 described species in Saropogon.

See also
 List of Saropogon species

References

Further reading

External links

Asilidae genera
Articles created by Qbugbot

redpajama_set_name: RedPajamaWikipedia