What is Infrared?
Infrared is a form of electromagnetic radiation just like visible light, but is invisible to the human eye, with wavelengths between 700 nanometers and 1 millimeter. Although infrared is invisible to the human eye, it plays a significant role in technology and our daily lives. Some of the most familiar applications of it are remote controls for TVs, air conditioners, and home theater systems. For example, when a button is pressed on the remote, it sends an electrical signal to an infrared LED (Light Emitting Diode) in the remote. This LED then emits infrared light in a specific pattern corresponding to the command (like ‘volume up’ or ‘channel change’). Because infrared is a type of light, it requires a clear line of sight between the transmitter (remote control) and receiver (TV). If something blocks the light, the signal won’t reach the receiver. This is why you generally have to point the remote at the TV for it to work.
Why is Infrared crucial?
Infrared also plays a critical role in telecommunications, in particular in short-range wireless communication. Devices can transmit data to each other using infrared radiation. This is similar to how Wi-Fi or Bluetooth works, but with a more limited range and requires a direct line of sight between the devices. This type of communication is often used in personal area networks, like connecting keyboards and mice to computers. Many smartphones use infrared for ‘proximity sensing’ so the phone can detect when the phone is held up to the person’s ear and turn off the display to save battery. Infrared is also used in thermal imaging technology which is useful in a variety of fields. These include security where IR cameras, night-vision goggles, or heat-seeking missiles can ‘see’ in the dark by detecting the heat emitted by objects or people. In medicine, thermal imaging can help detect inflammation or changes in blood flow, and in energy auditing where thermal cameras can identify heat leaks in a building’s insulation. Infrared lamps are sometimes used in physical therapy to help relieve pain and increase circulation. It is also used in some types of security systems and in astronomy to observe objects in space not easily visible in the normal light spectrum.
Infrared isn’t harmful in everyday amounts. But any form of exposure to high levels of infrared radiation can be dangerous, potentially causing burns and eye damage. So, safety measures are necessary when working with devices that emit high levels of it.