I need to detect a hit by a laser pointer, or similar light source. The target will be about 16 inch square. Wondering if I put a sensor looking at the edge of a thick plastic piece, if it could pick-up internal reflected light. Distance from ten to fifty feet. Looked at similar threads, but not quite what I need. Looking for ideas. Tnx.

 

I need to detect a hit by a laser pointer, or similar light source. The target will be about 16 inch square. Wondering if I put a sensor looking at the edge of a thick plastic piece, if it could pick-up internal reflected light. Distance from ten to fifty feet. Looked at similar threads, but not quite what I need. Looking for ideas. Tnx.

A lens such as those used for PIR detectors? A white Fresnel-like pattern. If the beam hits it anywhere the spot is recognized. I don't know if the Fresnel part would even be necessary.