How to determine the handheld infrared thermometer optical resolution and signal processing
Determination of optical resolution
Optical resolution is determined by the ratio of D to S, which is the ratio of the distance between the pyrometer and the target, D, to the diameter of the measurement spot, S. The optical resolution is determined by the ratio of D to S, which is the ratio of D to S. For example, the handheld infrared thermometer Ti213 of the infrared era has a distance factor of 80:1, so if the target is 80 centimeters away, the diameter of the measurement range is 1 centimeter. If the pyrometer must be installed away from the target due to environmental conditions, but also to measure small targets, you should choose a high optical resolution pyrometer. The higher the optical resolution, i.e. the larger the D:S ratio, the higher the cost of the pyrometer.
Signal processing capabilities:
In view of the discrete process (such as parts production) and the continuous process is different, so the requirements of infrared thermometer with multi-signal processing capabilities (such as peak hold, valley hold, the average value) can be selected, such as temperature measurement conveyor belt on the bottle, it is necessary to use the peak hold, and the output signal of its temperature is transmitted to the controller. Otherwise the pyrometer reads out the lower temperature value between the bottles. If peak hold is used, set the pyrometer response time slightly longer than the time interval between bottles, so that at least one bottle is always in the measurement.
Introduction to determining the response time of an infrared pyrometer
Response time indicates how quickly an infrared thermometer responds to a change in the measured temperature, defined as the time it takes to reach 95% of the energy of the final reading, which is related to the time constants of the photodetector, signal processing circuitry and display system. Some infrared thermometers have a response time of up to 1ms, which is much faster than contact temperature measurement methods. If the target's movement speed is very fast or measure the target of rapid heating, to choose a fast response infrared thermometer, otherwise it can not reach a sufficient signal response, will reduce the measurement accuracy. However, not all applications require a fast response infrared thermometer. For stationary or target thermal processes there is thermal inertia, the response time of the pyrometer can be relaxed requirements. Therefore, the choice of the response time of the infrared thermometer should be adapted to the situation of the target to be measured. Determine the response time, mainly based on the target's speed of movement and the target's temperature change rate. For stationary targets or targets involved in thermal inertia, or the speed of existing control equipment is limited, the response time of the pyrometer can be relaxed requirements.
