Study Of The Laser Absorption Radiation Thermometry

In theory,radiation thermometer has many advantages,such as no upper limit of temperature measurement,fast response speed and so on.In practical application,the application of radiation temperature measurement technology is becoming more and more widely.But the traditional radiation temperature measurement technology will be influenced by the target emittance change,the ambient radiation and the gas absorption in the optical path.The actual temperature measured by the radiation temperature measuring instrument deviates from the real temperature,which limits the application of the radiation temperature measurement technology.Laser absorption radiation thermometry(LART),as a new theory of temperature measurement,was first studied in German PTB in the 60 s of last century.Then this method was developed in Britain and France in 90 s,and then further studied as a European cooperation project to solve the real temperature measurement problem in industry.The method of laser absorption radiation temperature measurement breaks through the traditional idea that the temperature field is the advantage of radiation temperature measurement without destroying the temperature field in the field of radiation temperature measurement.By using the laser method,the temperature field of the target is destroyed and the rapid temperature rise response of the target surface is measured.In theory,it can completely eliminate the influence of emissivity and environmental radiation and so on.It has a very broad application prospect.This paper focuses on the following aspects: laser absorption and radiation thermometry.First of all,the development status and main research methods of laser absorption temperature measurement technology are introduced respectively,and its research significance is clarification.According to the previous research methods,the laser absorption radiation temperature measurement method is summed up as two modes of continuous laser and periodic laser,of which the periodic laser mode can be divided into two methods: single laser and double laser.Secondly,we deduce the temperature measurement principle of the two models and establish the corresponding temperature measurement model,which will provide a theoretical basis for future research.Then,a set of experimental device was set up to verify two methods of temperature measurement under the periodic laser mode,and the optical path and the main components of the experimental device were introduced.A data acquisition program and a lock-in amplifier program are compiled by using the PXI box in the laboratory to replace some hardware functions,so as to reduce the experimental cost.Finally,the experimental verification of the performance of the device is carried out.The validity of the detection signal is proved by comparing the detection results with the simulation results.The calibration experiments and the temperature measurement experiments are carried out respectively,and the temperature data measured by the infrared thermometer used in the laboratory are compared,and the practicability of the temperature measurement method is verified.From the experimental results,the experimental device designed in this paper achieves the function of temperature measurement,and achieves the desired design goal for the existing samples,which is stable in temperature measurement.