Detecting UV laser (405 nm)

Other Hardware General Electronics
1

Hi Everyone,

What is the cheapest way to have the arduino detect when a UV laser is hitting it? Right now, I'm thinking of using a photocell, but am not sure if it will be sensitive to 405nm.. Also read somewhere that simple LEDs can be used as sensor too. In that case would it have to be a UV led? Looking for maybe the top 3 cheapest methods.. Also, the smaller the solution, the better.

Thanks again so much!

2

It will be sensitive. Photodiodes detect photons above a threshold energy, and blue
is the most energetic. The only reason it would fail would be an explicit filter has been
added. A UV LED is about the only kind that might have problems (well white LEDS too
since they have a fluorescent layer).