IR (Infrared) Obstacle Detection Sensor Circuit is used to detect the obstacles, It is the combination of IR sensor circuit and IR Transmitter circuit.


There are various applications of Infrared(IR) sensors inclusive of television remote controllers, burglar alarms, and object counters. Right here we’ve got used infrared sensors (IR LEDs) to make an item-detection circuit and additionally a proximity sensor for course-monitoring robots. The primary idea is to transmit the infrared light via an Infrared led, which is then meditated with the aid of an impediment beforehand and sensed with the aid of the receiving led.

Components Required

IC1: LM358


  • R1: 220 Ohm
  • R2: 120 Ohm
  • R3: 10K Ohm
  • R4: 220 Ohm

IR Led1: IR Transmitter LED

IR Led2: IR Receiver LED

LED1: Any Color LED

VR1 : Variable resistor / Trimmer :10K

Zener Diode: 2.2V

Transistor T1: BC548


IR Sensor circuit

IR Sensor circuit

Working Enhancement

This circuit comprises the transmitter and receiver sections. The transmitter part generates the IR signal, it hits the obstacle and reflects back.The reflected signal is received by IR sensor. When the IR sensor received the signal, it generates high output and LED turns ON. Turning LED ON indicates the obstacle is present.The range of the transmitter increased up to 5 meters by using the convex lens.

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