Definition
The dual laser infrared thermometer is a non-contact temperature measurement instrument that measures the temperature by detecting the infrared radiation energy emitted by the surface of the target object, and is equipped with two beams of visible laser light to indicate the center of the measurement area. This instrument is suitable for situations where fast and safe surface temperature measurement is required, especially in the fields of electric power, metallurgy, chemical industry, food processing and scientific research experiments.
Principle
The dual laser infrared thermometer works based on the law of blackbody radiation. All objects above absolute zero emit infrared radiation, and its radiation energy has a functional relationship with the surface temperature of the object. The infrared sensor inside the instrument receives the radiation energy of the target, converts it into an electrical signal, and then calculates the temperature value through built-in algorithms and calibration parameters. The meeting point of the two laser beams usually indicates the center position of the measured spot, helping the user to position it accurately. Its core calculation formula can be expressed as:
E = εσT4
where E is the radiation energy, ε is the surface emissivity of the measured object, σ is the Stefan-Boltzmann constant, and T is the absolute temperature.
Measurement method
When using a dual laser infrared thermometer, make sure that the laser point is aligned with the area to be measured. The instrument measures the average temperature of the area covered by the laser junction, which depends on the optical resolution of the instrument and the measurement distance. During operation, attention should be paid to keeping the instrument stable, avoiding direct exposure to strong environmental light, and setting appropriate emissivity parameters according to the properties of the material being tested. Measurement results are usually read directly on the display, and some models support data logging and transmission.
Influencing factors
Measurement accuracy is influenced by various factors. The emissivity of the object surface is a key parameter, and the emissivity of different materials varies greatly, and inaccurate settings will lead to system errors. Environmental conditions such as air, dust, steam, or strong electromagnetic fields can interfere with radiation transmission. It is also important to note that the distance is too far away may cause the spot to be larger than the target area, and the mixing temperature between the background and the target is measured. In addition, the cleanliness of the instrument's own optical system, ambient temperature stability, and battery voltage can also affect the readings.
Application:
In the industrial field, this instrument is often used to monitor the operating temperature of electrical connectors, transformers, and motors to prevent overheating failures. In metallurgy and casting processes, it can be used to measure the surface temperature of molten metal or heat-treated components. In food processing, it is suitable for monitoring the temperature distribution of baking and drying processes. In the laboratory, it can be used for non-contact temperature measurement in experiments such as materials research and thermal process analysis. Its non-contact nature makes it suitable for measuring moving objects, live equipment, or corrosive substances.
Selection
Measurement needs should be comprehensively considered when selecting. The temperature range should cover the maximum and minimum temperature points of the intended application. Optical resolution is typically expressed as a distance spot ratio, with high ratios suitable for measuring small-sized targets. The short response time is good for capturing rapid temperature changes. The adjustable range of emissivity should meet common material requirements. The environmental protection level must be adapted to the site conditions, such as dust and water resistance. In addition, you can pay attention to whether the data interface, display type, laser indication and other auxiliary functions are in line with the workflow. It is recommended to refer to relevant industry standards, such as ASTM E1256 and other guidance documents on the use of infrared thermometers, and verify the instrument's performance in combination with actual tests.