Intruder Detection System Using a Laser Torch

Introduction

An Intruder Detection System Using a Laser Torch is a simple security project that detects unauthorized entry. It uses a laser beam, an LDR (Light Dependent Resistor), and a buzzer. When the laser beam is blocked, the buzzer sounds to alert users.

Components

Laser torch
LDR
BC547 transistor
Buzzer
9V battery
10 kΩ resistor
Connecting wires

Working

The laser beam continuously falls on the LDR. When an intruder interrupts the beam, the LDR detects the change in light, the transistor switches on, and the buzzer produces an alarm.

Applications

Home security
Offices
Banks
Warehouses

Advantages

Low cost
Easy to build
Low power consumption
Quick intrusion detection

Conclusion

This project is a simple, reliable, and affordable security system. It demonstrates how a laser and an LDR can be used to detect intruders effectively.

📷 Images to add:

Circuit diagram
Working model
Laser beam focused on the LDR