2020-06-30 17:10
Infrared thermal imagers were originally used in the military industry, and later were widely used in civil industries, such as power, railway, construction, petrochemical, coal, etc. Infrared thermal imager is a special instrument, with a lot of its own special parameters, so there are so many special functions, the following one by one to introduce the infrared related parameters.
1. Resolution
Like the visual camera pixels, infrared thermal camera resolution is defined as 160*120, 384*288, 640*480, and 1024*768.
2. The Focal Length
The distance from the center of a lens to its focal point, usually expressed in terms of f and usually in mm (mm). The greater the focal length, the farther the image can be clearly imaged.
3. The Temperature Measurement
Temperature range: The temperature range that can be measured by infrared thermal camera.
Accuracy of temperature measurement: the difference between the measured result and the actual result. The temperature accuracy of the general thermal imager is expressed as ±2℃ or ±2% of the reading, and the larger is taken.
4. Noise Equivalent Temperature Difference (NETD)
Thermal sensitivity describes the minimum temperature difference detectable by an infrared thermal camera. The smaller the thermal sensitivity value, the higher the sensitivity and the clearer the image.
5. Frame Frequency
The amount, in Hertz (Hz), of images taken, processed and displayed by a thermal imager in one second. The faster the response of the sensor, the higher the processing speed of the internal circuit, and the larger the frame frequency.
6. Viewing Angle
Represents the maximum spatial angle range that can be observed when the position of the thermal imager is fixed.
7. Spatial Resolution
Also known as angular resolution, the ability of a thermal imager to identify the minimum distance between two adjacent targets (milliradians, MRAD).
8. Spectral Response
Spectral response refers to the response of infrared thermography to the incoming radiation of various objects.
9. The Emissivity
The ratio of the radiant capacity of an object to that of a black body at the same temperature.
The surface emissivity of an object affects the accuracy of temperature measurement. In actual temperature measurement, the emissivity value can be modified.
10. The Absorption Rate
The ability of an object to receive radiation from outside.