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There are multiple types of alarm systems and sensors available for them. While low-powered lasers could be used, they are not usually. More common is what is called a PIR, or Passive Infra-Red detector. These detectors usually give a "cone" of infrared light which detects movement, whereas a laser beam would need to be "broken" (the beam would need to be interrupted). Because of the coherent nature of a laser beam (the beam travels in a narrow, straight path), compared to the wide coverage of a PIR motion sensor, lasers are rarely used.
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Why is infra-red dangerous?
Infra-red by itself is not dangerous at all. It is around us everyday. But I am sure that you are actually curious about infra-red LASERS. If shined into the eyes, IR Lasers can burn and permanently damage the retinas.
What does PIR stand for in alarms?
Passive Infra Red. Units that detect movement.
What is the meaning of electronic distance meter?
an Electronic Distance Meter (EDM) is a device that uses infra red or lasers to measure distance, removing the need for tape etc
What has the author Alistair F Phillips written?
Alistair F. Phillips has written: 'Temperature dependence of the radiative and non-radiative currents in visible and near infra-red semiconductor lasers'
Who invented the infra red waves?
Will Young invented the Infra Red Waves in 1943
When was Infra-Red - song - created?
Infra-Red - song - was created on 2006-06-19.
What is the Infra red?
vibrating molecules relase infra-red radiation (that's hot things)
How are infra red images taken?
anything warm rleases infra red waves the hotter an object is the more it releases. an inrer red camra detect infra and makes an image out of it.
What is the source of infra-red?
vibrating molecules relase infra-red radiation (that's hot things)
Where is infra red radiation emmited from?
Hot objects emit infra-red radiation. E.g. the human body.
What do you use infra red for?
it can be used for many things. we use it in lasers, but it is most commonly used by SWAT teams and police officers to locate people, animals, etc. that cannot be seen using body heat.
What are fire alarms?
RED
