Here is a demo of a laser/photoresistor transmitter/receiver.
On one Arduino is connected a laser. On another is connected a photoresistor. Data is transmitted from one to the other. Serial output on the receiver side shows the received packets.
My bench tests show 100% transmit/receive accuracy, but I’ve yet to apply the config to a practical across-the-room type test. Also, external light conditions may affect the code’s interpretation of on/off that the bench tests avoid (as I have the laser just an inch from the photoresistor in the test.)
I don’t actually have a practical need for this at this time, but having received a bag of lasers with photoresistors (amazon) I just had to try something.
Maybe someone wants to make a library out of this concept.
LaserXmit.ino (1.72 KB)
LaserRecv.ino (7.9 KB)