I want to build a grid 20cm x 20cm (8in x 8in) that detects laser hits from one of these
. It appears to be a simple IR/red laser.
I'd like the grid to be able to indicate where the hit was (row and column), if possible. Mainly I want to use it for timing. The receivers Laser Lyte sells for use with the emitters indicate a hit, but not how long it took (and the receivers appear to be pretty small as well).
My first thought was to create a 2D array of phototransistors, but I'd probably need to space them every 5mm or so, which would mean 1600 transistors, which would be nearly 1000USD.
Is there a better way to build this?
Alternatively, I suppose, I could buy their receiver and tap into the signals that indicate start and a hit, amplify them, and feed them to the arduino to calculate and display the time.