Many electrical appliances use infrared remote control, so what is the working principle of infrared remote control? First, let's take a look at what is infrared.
The visible light that human eyes can see is arranged from long to short wavelength, which is red, orange, yellow, green, cyan, blue and purple in turn. The wavelength range of red light is 0.62 ~ 0.76 micron; The wavelength range of violet light is 0.38 ~ 0.46 μ m. The light shorter than violet light is called ultraviolet light, and the light longer than red light is called infrared light.
Infrared remote control uses the near infrared ray with the wavelength of 0.76 ~ 1.5μ m to emit control signals.
The commonly used infrared remote control system is generally divided into two parts: transmitting and receiving.
The main component of the transmitting part is infrared light emitting diode. It is actually a special kind of light emitting diode. Because its internal material is different from ordinary light-emitting diodes, a choke will occur when a certain voltage is applied at both ends.