5V 5mW Laser Sensor Module for Arduino 650nm

Ok, calling it a sensor is a bit off… as it only is cabable of beeing turned on and off again. Measurements for a 0.85 EUR device would be a real surprise, but hey – the cats still love the beam which is easily mountable to an robotic arm consisting of two 28-BYJ stepper motors 🙂

 void setup ()
 {
   pinMode (13, OUTPUT); 
 }

void loop () {
    digitalWrite (13, HIGH); / / open the laser head
    delay (1000); / / delay one second
    digitalWrite (13, LOW); / / turn off the laser head
    delay (1000); / / delay one second
 }