Using a Phototransistor to Detect "Movement"

[TCreatorO]

great Job!, you can elaborate on that, by adding a relay and a 9v battery to to turn on a siren/buzzer :). I made a similar one out of a broken player, hand-held laser, radio-shack buzzer, 2AA batteries to operate the photo resistor and LED's and a 9v battery to power the buzzer and a Test mode so that while adjusting the mirrors you don't have to hear the annoying buzzer lol only an amber LED lol. hope I have inspired you to continue this project and make it better