have you made any of the alarm systems that you often see in spy films where there are red lasers that if they are

Question: have you made any of the alarm systems that you often see in spy films where there are red lasers that if they are touched sound an alarm ? (if you havent are they possible?)
- Keywords:
  film,
  lasers,
  spy
Asked by sashagrace to Amanda on 18 Jun 2013.
- Amanda Lewin answered on 18 Jun 2013:
  
  The intruder alarm systems you see in the movies have been jazzed up a bit to make them look more complicated than they really are! But the principle is the same. There is a beam of either infer red waves or microwaves that is passed out by the detector, if anything breaks the beam it will trigger the alarm. You can’t actually see the beam in real life though and you don’t need as many as they have on TV!
  
  There is also a type of smoke detector called a beam detector that works in a similar way. It passes out (or emits as we call it) an infer red beam and if there is a fire the smoke will break the beam setting off the fire alarm. Beam detectors are great where there are high ceilings but if you put them too low people could accidentally set them off which would be bad!

Question: have you made any of the alarm systems that you often see in spy films where there are red lasers that if they are touched sound an alarm ? (if you havent are they possible?)