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IR Photodiode Explained

 

IR Photodiode

Definition

An IR photodiode (Infrared photodiode) is a semiconductor device that detects infrared radiation and converts it into an electrical current.

How It Works

  • IR light falls on the photodiode
  • Electron-hole pairs are generated
  • Electrical current is produced
Light Energy → Electrical Energy (Current Signal)

It is usually operated in reverse bias for faster response.

Characteristics

  • Detects infrared radiation (700 nm – 1 mm)
  • Fast response time
  • Low power consumption
  • Works in low-light or dark conditions

Applications

  • TV remote control receivers
  • Obstacle detection sensors
  • Night vision systems
  • Fiber optic communication
  • Motion detection systems

Example

When you press a TV remote button, it sends infrared signals. The IR photodiode in the TV receives these signals and converts them into electrical data.

IR photodiode is an invisible light detector that converts IR light into electrical signals.

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