Infrared light-emitting diodes are similar in appearance to ordinary light-emitting diode LEDs, emitting infrared light. Tube voltage drop of about 14V, the operating current is generally less than 20mA, in order to adapt to different operating voltages, the circuit is often series current-limiting resistors.
There are three commonly used wavelengths for infrared emitting tubes, 850nm, 875nm, 940nm, which are used in different kinds of products according to their wavelength characteristics
The 850nm wavelength is mainly used in infrared monitoring equipment, the 875nm wavelength is mainly used in medical equipment, and the 940nm wavelength is mainly used in infrared control equipment.