Infrared LED is a kind of diode that can emit infrared ray, and is usually used in remote control and other occasions. Commonly used infrared light-emitting diodes are similar in shape to LED, emitting infrared light. The voltage drop of the tube is about 1.4v, and the working current is generally less than 20mA. In order to adapt to different working voltages, the circuit is often connected with a limited current resistor.

The infrared light emitting diode is made of a PN junction made of a material with high infrared radiation efficiency (commonly used GaAs), and a positive bias voltage is applied to the PN junction to inject current to excite infrared light. The spectral power distribution is from 830 nm to 950 nm, and the half peak bandwidth is about 40 nm. Its biggest advantage is that it can completely avoid red storms (using 940-950nm wavelength infrared tubes) or only have weak red storms (red storms have visible red light), thus prolonging its service life. Light is an electromagnetic wave whose wavelength ranges from several nanometers (1nm=10-9m) to about 1mm (mm). What is visible to the human eye is only a part of it. We call it visible light. The wavelength range of visible light is 380nm~780nm. The wavelength of visible light is divided into red, orange, yellow, green, blue, and violet from long to short. The wavelength shorter than ultraviolet light is called ultraviolet light, and the wavelength longer than red light is called infrared light.

Commonly used infrared emission tube wavelength: 850nm, 870nm, 880nm, 940nm, 980nm

Relation between power and wavelength of infrared emission tube: 850nm>880nm>940nm

Peak wavelength: the energy distribution of the luminous object or object measured on the spectrometer, and the wavelength corresponding to its peak position λ p。

Power: unit: mW/sr, indicating the infrared energy radiated by the infrared tube (IRLED).

The radiation intensity (POWER) is proportional to the input current (If) and inversely proportional to the emission distance. Unit mW/sr: unit of infrared radiation intensity, which is the light power radiated from the unit solid angle (sr) of infrared light emitted by the emitter tube. The artificial increase of the power of the infrared transmitting tube can only temporarily increase the irradiation distance. Finally, the wafer attenuation is accelerated, resulting in the increasingly dark infrared light and the increasingly unclear night vision. The external light source of the irradiated environment is complex, and the infrared camera leaf cannot play its due role. Emission distance, emission angle (15 °, 30 °, 45 °, 60 °, 90 °, 120 °, 180 °), emission light intensity, wavelength. The above are physical parameters.