IR Sensor Information

Television remote controls use IR sensor technology.

Infrared radiation makes up part of the electromagnetic spectrum, and includes visible light, radio waves, ultraviolet right and gamma rays. Sensor devices, called IR sensors, detect this radiation.

Definition

IR sensor devices detect infrared wavelengths, or light made up of electronic radiation with a wavelength between 0.7 to 1000 microns, a system of measurement equal to one millionth of a meter. This wavelength range makes up the infrared band, which emits radiation temperatures detectable by IR sensors.

Emissivity

Emissivity is the measurement of energy-emitting characteristics of different materials or surfaces. An object's emitted, or produced, IR energy decreases or increases in proportion to its temperature. IR sensors use adjustable emissivity settings that enable them to obtain temperature measurements of different surface types.

Detection

An object's emitted energy reaches the IR sensor via the device's optic system, which in turn focuses the energy onto its photosensitive detectors. The detectors convert the IR energy into an electrical signal, which then is converted into a temperature value based on the object's emissivity. This value may be displayed on the IR sensor or converted as digital input and sent to a computer terminal for display.

References

• PCMag: Definition of: IR detector
• "Infrared Technology: Applications to Electro-Optics, Photonic Devices and Sensors"; A. R. Jha; 2000

Resources

• "Handbook of Infra-red Detection Technologies"; M. Henini and M Razeghi; 2002