- Electrical Instrument
- Sonic Toothbrush
- Digital engine analyzer
- Environmental Meters
- Non-contact voltage tester
- Digital tachometer
- Insulation Resistance Testers
- Ground resistance meters
- Other electrical test equipment
Principle and precision of the infrared thermal imager temperature limit
the infrared thermal imager is usually used by 9 ~ 14 bands of electromagnetic wave to realize imaging and detecting. According to the principle of blackbody radiation, any object in the outward radiation of electromagnetic wave, the higher the temperature, the shorter the wavelength of electromagnetic radiation. The temperature of the sun is very high, About 5700 K) So the sun radiation of electromagnetic wave at about 500 nm. And for normal temperature ( 27℃) Around the object, the radiation peaks of 10, and radiation power and temperature are related. So if there is a similar camera equipment, electromagnetic wave can detect 9 ~ 14, will be able to use the object's own radiation for imaging, without the need for external lighting light source. Because of the intensity of radiation and temperature are related, therefore, the brightness of the image is also related to the temperature of the objects are: the higher the temperature, the higher the radiation power, the strength of detected signal, the corresponding imaging will be bright. Therefore, the imaging device can be used to test the temperature distribution on the surface of the object. Because is to use its own radiation imaging object, requires no additional lighting light source, so at night can also imaging such as environment, similar night-vision goggles.
as a result of this is also known as infrared wave band of the electromagnetic wave radiation, so this kind of equipment is also referred to as the infrared thermal imager.
in the hardware point of view, the infrared thermal imager and the commonly used camera have similar structure, mainly including receiving the infrared camera, infrared wave infrared imaging and detecting the infrared wave infrared detector.infrared lens are similar to ordinary optical lens principle, namely through the infrared wave refraction control the direction of transmission, the realization of the aim of imaging. But with less material is of infrared wave absorption of germanium crystals, silicon, and sulfide glass, etc. Infrared detector which can detect the electromagnetic wave detector has a variety of technical implementation plan, including the uncooled infrared focal plane array detector, refrigeration type infrared detector, etc. But this kind of detector technology also is not very mature, performance needs to be improved. How to improve the performance of this kind of detector is a subject in industry and academia research. In the applications of test temperature, generally with lower cost, poor performance at the same time also some type of uncooled infrared focal plane detector.
the infrared thermal imager is often used in industry measurement, monitoring equipment plays an important role in applications such as temperature change. Because in the infrared wave is easy to penetrate the smoke at the same time, thus the infrared thermal imager is also often used in fire rescue mission.
in the outbreak of a new coronavirus infection due to a obvious symptoms are fever, so fast and exact measurement of body temperature is of great significance to the prevention and control of epidemic. Many testing site temperature measurement with infrared thermal imager the human body, its advantages includefast non-contact measurement reduce the cross infection monitoring field is bigger, to facilitate the traffic was bigger scenario for the human body target detection more
but the application of infrared thermal imager to measure temperature, in theory, there are a few restrictions, make its test object has certain error of absolute temperature. This restriction, in essence, is the infrared thermal imager to detect the intensity of the infrared wave not only related to the temperature of the object, but also with the emissivity of the object, the object associated with the distance of infrared thermal imager.object emissivity
object infrared radiation wave of power is not only related to its temperature, and the emissivity of the object itself, this is determined by the material properties of the object itself. The same temperature, different materials of emissivity of the object is different, the infrared thermal imaging result seems brightness is different. Infrared thermal imager, therefore, only if the user input the correct rate of radiation to the calibration is possible after a more accurate estimate the temperature of the object.