A Red Light Camera (short for red-light running) is a type of traffic enforcement camera that captures an image of a vehicle that has entered an intersection despite the traffic signal indicating red (during the red phase). By automatically photographing vehicles that run red lights, the photo is evidence that assists authorities in their enforcement of traffic laws. Generally, the camera is triggered when a vehicle enters the intersection (passes the stop-bar) after the traffic signal has turned red.
Red light cameras are typically installed in protective metal boxes attached to poles at intersections, which are often specifically chosen due to high numbers of crashes and/or red-light-running violations.
Using the speed measured, the system predicts if a particular vehicle will not be able to stop before entering the intersection, and takes two photographs of the event.
The first photo shows the vehicle just before it enters the intersection, with the light showing red, and the second photo, taken a second or two later, shows the vehicle when it is in the intersection.
Details that may be recorded by the camera system (and later presented to the vehicle owner) include the date and time, the location, the vehicle speed, and the amount of time elapsed since the light turned red and the vehicle passed into the intersection. The event is captured as a series of photographs or a video clip, or both, depending on the technology used, which shows the vehicle before it enters the intersection on a red light signal and its progress through the intersection.
The data and images, whether digital or developed from the film, are sent to the relevant law enforcement agency. There, the information is typically reviewed by a law enforcement official or police department clerk, who determines if a violation occurred and, if so, approves issuing a citation to the vehicle owner, who may challenge the citation.
Studies have shown that 38% of violations occur within 0.25 seconds of the light turning red and 79% within one second. A few red light camera systems allow a “grace period” of up to half a second for drivers who pass through the intersection just as the light turns red.
Ohio and Georgia introduced a statute requiring that one second be added to the standard yellow time of any intersection that has a red light camera, which has led to an 80% reduction in tickets since its introduction. New Jersey has the strictest yellow timing provisions in the country as a result of concerns that cameras would be used to generate revenue; they have a statute specifying that the yellow time for an intersection that has a red light camera must be based on the speed at which 85% of the road’s traffic moves rather than be based on the road’s actual speed limit.
You can find more info about red light camera product history and old models on Wikipedia.
Red Light Camera is a traffic enforcement camera that captures image of vehicles which has entered an intersection in spite of the red light.
Innovative red light camera systems for combined speed and red light enforcement.
Here is MTP Red Light Violation Enforcement Radar Sample Videos,
MTP RED LIGHT Violation Radar Data Sheet