pi_what3
Ir LED vs Photointerrupter
Ir LED (Infrared LED)
Ir LED (Infrared LED) is a photoelectric conversion element that converts electrical energy into optical energy, with an emission wavelength between 800nm to 950nm.
Materials used include GaAs and GaAlAs.
Infrared LEDDownload datasheet
Photointerrupter
Since photointerrupters (or phototransistors) combine a photodiode and transistor, the base current of the transistor is input as light. Silicon with a sensitivity between 400nm and 1100nm is used.