Conditions and advantages of infrared thermometer
The infrared thermometer is composed of optical system, photoelectric detector, signal amplifier, signal processing, display output and other parts. The optical system gathers the target infrared radiation energy in its field of view, and the size of the field of view is determined by the optical parts of the thermometer and its position.
Principle of infrared thermometer
The infrared human body thermometer is composed of an optical electronic system, a photoelectric detector, a signal intensifier, and a signal analysis and display information output. The optical electronic system gathers the infrared radiation kinetic energy of the target in its field of view, and the infrared kinetic energy focuses on the photodetector and changes into a relative electronic signal, which is then calculated and changed into the temperature value of the measured target.
The light waves emitted by the sun are also called electromagnetic waves. Visible light is an electromagnetic wave that the human eye can perceive. After being refracted by a prism, seven colors of red, orange, yellow, green, blue, blue, and purple light can be seen.
Infrared rays are part of these electromagnetic waves, and together with visible light, ultraviolet light, X-rays, gamma rays, and radio waves, they form a complete and continuous electromagnetic spectrum. As shown in the figure above, electromagnetic radiation with a wavelength ranging from 0.76 μm to 1000 μm is called infrared radiation. Any object with a temperature above absolute zero (-273.15°C) is constantly emitting infrared radiation (thermal radiation). It is invisible to the human eye, and the wavelengths of external radiation are different at different temperatures. For the human body, the body temperature is relatively constant. Thermal imaging measures the temperature by detecting the thermal radiation on the surface of the human body. Based on the big data of human body temperature measurement, it is mapped to the internal temperature of the human body through a temperature measurement algorithm.
Conditions of use for infrared thermometers
1. Ambient temperature. If the infrared thermometer is suddenly exposed to an ambient temperature difference of 20°C or higher, allow the instrument to adjust to the new ambient temperature within 20 minutes.
2. Only measure the surface temperature of the object. Portable infrared thermometers cannot measure the internal temperature of objects
3. Pay attention to environmental conditions. Steam, dust, smoke, etc. will block the optical system of the instrument and affect accurate temperature measurement.
4. Locate hotspots. To find a hot spot, first use the instrument to aim at the target, and then scan up and down on the target until the hot spot is identified.
5. The portable infrared thermometer cannot measure temperature through glass. Glass has very specific reflective and transmissive properties that prevent accurate temperature readings, but can be measured through the infrared window. Infrared thermometers are best not used for temperature measurement on bright or polished metal surfaces (stainless steel, aluminum, etc.).
Advantages of infrared thermometers
1. Non-contact measurement: Times Ruizi infrared thermometer does not need to touch the inside or surface of the measured temperature field, so it will not interfere with the state of the measured temperature field, and the thermometer itself will not be damaged by the temperature field.
2. Wide measurement range: Because it is a non-contact temperature measurement, the thermometer is not in a higher or lower temperature field, but works at a normal temperature or under the conditions allowed by the thermometer. Under normal circumstances, it can measure minus tens of degrees to more than three thousand degrees.
3. Fast temperature measurement speed: that is, fast response time. As long as the infrared radiation of the target is received, the temperature can be fixed in a short time.
4. High accuracy: Infrared temperature measurement will not destroy the temperature distribution of the object itself like contact temperature measurement, so the measurement accuracy is high.
5. High sensitivity: As long as there is a small change in the temperature of the object, the radiation energy will change greatly, which is easy to detect. It can perform temperature measurement and temperature distribution measurement of tiny temperature field, as well as temperature measurement of moving or rotating objects. It is safe to use and has a long service life.
