Target size and optical resolution of double-color infrared thermometer
Infrared thermometers can be divided into monochrome thermometers and two-color thermometers (radiation colorimetric thermometers) based on their principles. For monochrome thermometers, the area of the measured target should fill the thermometer's field of view during temperature measurement. It is recommended that the size of the target being tested exceed 50% of the field of view size. If the target size is smaller than the field of view, the background radiation energy will enter the visual and acoustic symbols of the thermometer and interfere with the temperature reading, causing errors. On the contrary, if the target is larger than the field of view of the thermometer, the thermometer will not be affected by the background outside the measurement area.
For the Raytek dual color thermometer, its temperature is determined by the ratio of the radiated energy within two independent wavelength bands. Therefore, when the target being measured is small and not filled with the field, and there is smoke, dust, or obstruction on the measurement path that attenuates the radiation energy, it will not affect the measurement results. Even in the case of energy attenuation of 95%, the required temperature measurement accuracy can still be guaranteed. For targets that are small and in motion or vibration; Sometimes targets that move within the field of view or may partially move out of the field of view, using a dual color thermometer is the best choice under these conditions. If it is impossible to directly aim between the thermometer and the target, and the measurement channel is bent, narrow, or obstructed, a dual color fiber optic thermometer is the best choice. This is due to its small diameter, flexibility, and the ability to transmit optical radiation energy through curved, obstructed, and folded channels, making it possible to measure targets that are difficult to approach, have harsh conditions, or are close to electromagnetic fields.
Optical resolution of dual color infrared thermometer
The optical resolution (distance and sensitivity) is determined by the ratio of D to S, which is the ratio of the distance D between the thermometer and the target to the diameter S of the measurement spot. If the thermometer must be installed far away from the target due to environmental conditions and needs to measure small targets, a high optical resolution thermometer should be selected. The higher the optical resolution, i.e. increasing the D: S ratio, the higher the cost of the thermometer.
