How Do Laser Security Systems Work?
In real life, laser security beams are often invisible, which enhances their effectiveness. Image Credit: tiero/iStock/GettyImages  Like so many things, laser security systems look way cooler in the movies than they do in real life. But while a real laser security alarm doesn't actually involve a giant beam of red light being shot across your living room, which is a good thing, because it's a lot easier for criminals to avoid crossing bright red beams of light than invisible wavelengths of light. In fact, some lasers are hooked up to a silent alarm, so burglars have no idea they've triggered the alarm until the police arrive. Advertisement  Tip Laser alarms work by projecting light into a detector, which sends a specific voltage into sensing electronics. When the detector no longer senses the light, it changes this voltage, causing the sensing electronics to turn on the alarm. Components of a Laser Alarm  Laser security systems used to be difficult to install and rarely available to anyone other than the super-rich. Now, there are dozens of different home security systems on the market that utilize lasers and can effectively protect everything from small apartments and businesses to large areas of property. Most home laser security systems consist of two parts: a basic alarm unit and an infrared motion detector. Laser security systems of the past relied on connections wired to a keypad, requiring the customer to use special codes to arm and disarm the system. Since the majority of laser security systems are now wireless, the units can be turned on or off with a wireless remote or, in some models, by touch tone phone from anywhere in the world. Advertisement  How Laser Security Systems Function  The basic sensing component of a modern laser security system is an infrared motion detector. The motion detector contains four parts: the laser, the mirrors, the detector and the sensing electronics. An infrared motion detector works by projecting a beam of light that shoots across a space into a series of mirrors and finally into a detector, which emits a particular voltage into the sensing electronics as long as the laser hits it. When the beam of light is broken, the detector changes its voltage output into the sensing electronics, which then trigger an alarm. Advertisement  If infrared sensors are placed strategically, the beams of light will make it impossible for an intruder to come into the area without the sensor being alerted. The sensor, which is connected to the basic alarm unit through a wireless connection, then triggers the basic unit to alert the monitoring service through which the customer purchased the security plan. The monitoring service will contact the home and, if no response is received, will contact the police. In most models, the basic unit also sounds a loud alarm, though some systems use a silent alarm that contacts the police without notifying the suspected criminal. Advantages and Disadvantages  Laser security systems have many advantages. They are simple to install and can be used effectively inside or outside a home. These basic parts of a larger security system can be used as a highly effective perimeter alarm for property boundaries or even for pools, where customers can have the lasers set to detect when small children come within a set number of feet from the edge of the water. Indoors, the sensors utilize normal power outlets and telephone jacks; outdoors, the sensors can be hidden beneath plants and bushes and will not harm lawns or other vegetation. Advertisement  However, laser security systems can be prohibitively expensive. While some home alarm system plans allow for customers to target one room, plans that protect large amounts of land or an entire house will cost much more and can be difficult for many customers to afford.