According to :LED as light sensor:A LED is simply a diode that has been doped specifically for efficient light emission and has been packaged in a . These will help you understand how the detection angle of an LED used as a sensor matches its emission angle when used as a light source:. Using an LED as a light detector is nothing new (see this 20Electronic Design article). However, it seemed like a cool trick that deserved . This capability may be used in a variety of applications including . I show you how to use an LED as a light sensor, Any LED will work for this, not just IR but it will have it’s.
A brief tutorial on how an LED can be used as a Light Sensor, or Photodiode. A little used technique is to use an LED as both a light emitter and a light detector. Just like a dog walking on its hind legs one marvels, not that it is done well, but . Using LEDs as photodiodes (light sensors):.
Background: LEDs are commonly used as lights, but then can also be used as photodiodes to detect light. This circuit shows how to use an ordinary LED as a light sensor. It makes use of the photovoltaic voltage developed across the LED when it is .