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Traceable temperature sensor calibration principle is to use the quasi-continuous laser sensor surface temperature rise, the radiation thermometer and calibration of sensors simultaneously measure the heat source. Dynamic calibration of the principle is now widely used in thermal equipment, power machinery, rocket engines, nuclear engineering and other disciplines. Study transient surface temperature sensor dynamic calibration purposes, the use of traceable, rapid changes in temperature signal, the detection time of the dynamic response of the temperature sensor characteristics, and the results of temperature correction, making it the final results of the data more close to the real temperature signal curve, so as to achieve the purpose of reducing the dynamic response error. For transient surface dynamic calibration system, the laser spot size adjustable: If the school the laser spot on the sensor probe is too small, the sensor uneven heating will produce a large error, the calibration results are inaccurate, if the spot is too large, Although the heat evenly, but the system response time increases, the same result in inaccurate calibration results. So that it can not ensure that the sensors or micro structure is uniformly heated. The oscilloscope acquisition data acquisition length is too small, the rate is too low, the drawbacks, this paper proposes a surface temperature calibration system based on transient off-axis parabolic reflector, the principle is the first plane mirror laser reflector to off-axis parabolic mirror surface , whereby the mirror again to the focused laser beam, as compared to using a single lens, the elimination of the thermal lens effect and the spherical aberration, and to simplify the original light path system, and can obtain a better quality of the spot, the focus spot shape is also more tolerant can change the spot size of the peak power by changing the size of the focal length, so that adjustment is more simple, and its ZEMAX software emulation. 4-channel data acquisition card data acquisition system, infrared detectors, thermocouple temperature sensor measurement, the higher acquisition rates, more flexible control. The new design, the time constant of the transient calibration system based on off-axis parabolic testing laboratory experiment to verify the feasibility of the system design. According to the layout of the system as a whole, the mounting base on the shield casing and off-axis parabolic reflector design can be opened simultaneously, so that the shield casing bilateral placed one side of the infrared detector is designed to push-pull to open the way, so that The detector position adjustment is more convenient.
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