Laser auto-switch off

[sdietric]

I am trying to use a laser for decorative reasons along a wall. It has to be pretty strong, trying to make a big pattern along the wall with various mirrors.

Now someone could come in put a mirror in the bean which reflects and could blind someone.

I was wondering if anyone knows about an auto-off mechanism that as soon as a laser beam is interrupted switches of the laser. Is there any such apparatus / electronic out there that does an auto-switch-off? Or any other ideas how to switch off a laser when the beam is interrupted?

I was thinking maybe a secondary, much weaker laser, that would run in parallel and provide this function, but not sure how fast photo diodes react.

Thanks so much!

 

[APEX1]

Look into the laser alarm system, that could give some insight on how it all works. I'm sure it could be done

 

[sdietric]

Thanks, yes, I am sure it can be done, it's just that I need something that switches off the strong and dangerous laser when interrupted and switches it back on when clear. A laser alarm system just sounds an alarm (which could of course be used to switch off the laser), but how then determine how to switch it back on when the path is clear again?

But maybe indeed using something like the laser alarm system using a second weaker laser to switch off the other laser when interrupted. And then switch the strong laser again when the weak laser (that always stays on) is clear again.

Question: Are there wireless systems for remotely switching off lasers? Trying to do this without running wires across the wall...

Thanks so much!

Look into the laser alarm system, that could give some insight on how it all works. I'm sure it could be done

 

[APEX1]

Question: Are there wireless systems for remotely switching off lasers? Trying to do this without running wires across the wall...

Thanks so much!

I'm not sure.. If Alan sees this he might be able to give you a much better in-depth answer

 

[marcuspeh]

just like what noobphraser215 has said, a laser security should do the trick but you need to tweak the circuit. Once the modded circuit is built, if someone steps in front and blocks the laser, the relay will turn off the laser. When they are no longer in front, the laser switches on again

These is what you have to do:
1. Swap the position of the LDR at the bottom with the 150k ohm resistor
2. Change the resistor to a lower value unless the laser is directly pointing at the LDR
3. Change the LED to a relay and connect it to your laser

 

[APEX1]

Can't much better than that. Nice diagram dude