Infrared light-emitting diodes made of high-efficiency infrared radiation materials (commonly used gallium arsenide GaAs) made of PN junction, plus a forward bias to the PN junction current injection to stimulate infrared light. The spectral power distribution of the center wavelength of 830 ~ 950nm, half-peak bandwidth of about 40nm. Its biggest advantage is that it can prolong the service life without any red storm (using 940 ~ 950nm wavelength infrared tube) or only weak red storm (red storm with visible red light). Light is an electromagnetic wave whose wavelength ranges from a few nanometers (1 nm = 10-9 m) to about 1 millimeter (mm). Visible to the human eye is just a part of it. We call it visible light. The wavelength range of visible light is from 380nm to 780nm. The wavelength of visible light is short, red, orange, yellow, green, blue, blue and violet Known as the UV light, the wavelength is longer than the red light is called infrared light.