In this project, we will learn how to make a laser-based security system with an LDR and an Arduino. Whenever any object will obstruct the LASER ray the buzzer alarm will start ringing. If the LDR. We need safety and security for our valuable things, to protect our property simple and robust security alarm circuit designed by using easily available components. We know the LASER (Light Amplification by Stimulated Emission of Radiation) light has high strength focused light rays, in this. How to Make a Laser Security System Using Arduino and LDR: You've probably seen a movie where a valuable item is protected by a grid of laser beams. This system utilizes laser beams to create a protective perimeter and detect unauthorized intrusions. The fundamental concept revolves around the.