Hi,
Is there a sensor(relatively cheap) that can detect when a laser light hits it? I am trying to use a laser in an escape room that will need to be directed to the correct location to trigger another effect. Looking for options to detect the laser light.
Thanks.
You'll be looking at IR sensors. Maybe as simple as a photodiode.
On the laser side (that's at least how it's done in laser games) a combination of red and IR. Red for the human to see where they're aiming; IR for the sensor so it's not triggered by ambient light and as it's an escape room I assume sunlight with all its IR isn't an issue.
A basic LDR with appropriate brightness control would be dirt cheap.
Brewskio1:
Hi,Is there a sensor(relatively cheap) that can detect when a laser light hits it? I am trying to use a laser in an escape room that will need to be directed to the correct location to trigger another effect. Looking for options to detect the laser light.
Thanks.
laser light is still light, any optical detector will work.
If you want to only detect the laser light in the presence of ambient light, that's harder - you need
a narrow-band optical filter (expensive) to remove most of the ambient light.
For a fixed-direction beam you can use a directional sensor (photo diode behind a small hole perhaps) to
remove ambient light.
Laser light is directional, but it can reach the sensor from many different directions, and it should not matter for the player from where he shines the laser, only to where he shines it.
You'll have to find a way to be a lot bright than ambient. It's an indoor room so ambient isn't all that bright and there's little to no IR present. That's why I suggested IR - but as in #2 maybe an LDR and a red laser works as well. It depends on the relative brightnesses.
Another problem OP may have to address is the area of sensitivity. An LDR or photodiode is just a few mm across, it's hard to aim a hand held laser from a few meters distance exactly at such a point. The easiest to address this would be to give the laser a slightly diverting beam (some laser pointers have that option built in) to make a much larger target area. Disadvantage is that your relative brightness is much less and it's harder to see for the play where they're aiming, and for the sensor to sense it's being irradiated.
Can you modulate the laser beam? Adding a 38KHz carrier to the beam will make it a zillion times easier to distinguish from ambient light.