If you’ve played around with laser diodes that you’ve scavenged from ... So let’s have a peek. Laser Detector on 3D Printer Scrap First up is the detector, which is nothing more than a ...

An Arduino Uno and the relays ... [SilverJimmy] sourced his laser from eBay, but check out the engraver from earlier this year that used a DVD diode.

In this fun project an ultrasonic distance sensor is used to detect a “target” (i.e., a person, a cat, a burglar, etc.). The Arduino illuminates (blasts) the target using an inexpensive laser diode ...