Infrared is not visible to the human eye, but there are occasions when this is an advantage. The use of infrared led light beads is extensive, can not be summarized in a sentence, this article tries to do a classification from the industry applications.

Remote control

The most common use of infrared is for remote controls. Remote control widely used infrared LED to send control signals. Infrared light is not visible to humans, but can be detected by the receiver. Infrared LEDs are cheaper and simpler than traditional RF technology. Typical emission wavelengths are 850 nm or 940 nm. When a remote control button is pressed, the infrared LED is turned on for a short period of time, sending a signal in the form of a pulse code. Common encoding methods are RC-5, NEC, etc. Infrared led tubes for remote control are usually small plug-in packages.

Security/Night Vision Systems

In low light or no light environment, infrared lighting with the camera can form a clear image. So it is widely used in video surveillance, night vision, automatic navigation and other fields. Generally, infrared light near 850nm is used, which has a better ability to penetrate smoke than longer wavelength infrared light. Used for security infrared led also to plug-in small power mostly.

Sensors

Various types of sensors contain infrared transmitter and receiver tubes, which are used for distance measurement, motion detection, and human body sensing. Such as automatic door sensors in the transmitter and receiver tubes are placed relative to each other, the object can be detected when passing through and open the door. Car reverse radar also uses infrared ranging. In some measuring instruments are also using infrared to carry out size and appearance measurement.

Communication

Infrared light is used for short-range wireless communications, such as TV remote controls, infrared headsets, and IrDA cell phone interfaces. Infrared light travels quickly through air, glass, and plastic without affecting human health.

Medical

Infrared radiation can heat up skin tissue and increase local blood flow. It is used to treat muscle pain and post-traumatic pain. However, over-exposure can cause burns, so it is important to stay within safe dosage limits. Medical treatment usually use multi-band led, the most common is 660nm 850nm 940nm three-in-one package.

Anti-counterfeiting

An infrared security mark is placed on important documents to prevent illegal copying or counterfeiting. This mark is only visible under infrared light. To check for authenticity, the mark is illuminated with an infrared light source and inspected with an infrared camera.

Visual Inspection

Because long wavelength infrared light has better penetrability, it can see through surface wrappings to the interior. This characteristic is used for flaw detection in industry, and with machine vision systems, it can be used for quality inspection of food and parts. Commonly used wavelength bands are 1050nm 1300nm.