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laser trip wire? Answered

I need to build a laser security system. I already have an alarm that works by shorting two wires with a trigger switch there by activating the alarm. I want to activate this alarm with a laser trip wire. I don't want to get a whole security system I just want to get the laser emitter and the receiver. I can't find this part any where. If somebody could help me find this part I would apreciate it.



Are you looking for a pre-built system, or do you want to make your own circuit?

I want a system that will have an open circuit until the laser beam is broken and then it will close the circuit.


6 years ago

We have no idea where you are! Do you live in Antarctica?

Sorry I am in the US.

Standard laser pointer and an LDR photo cell will do it use a photo transistor if you need to use over a long distance.

If you want a totally invisible system use an IR transmitter and receiver set.

To be honest ordinary light from an LED will work if you put it in a tube to narrow the field of view.

The difficulty is getting and keeping them lined up you need some sort of adjustable system

i think you can use a photo cell, but look here. this guy uses a trip wire to activate the camera.
watch the video: http://www.radioshackdiy.com/project-gallery/pinewood-derby-instant-replay-system