Research On Infrared Temperature Measurement System Based On

Infrared thermal imager can get target infrared image, at the same time, it canmeasure the temperature of the target. The infrared thermal imaging temperaturemeasurement have several characteristics,such as non-contact, long distance, highsensitivity, high speed,wide temperature measuring range, and the measured targetcan be selected in the image, etc. At present, the common used infrared thermalimage for temperature measurement instrument, the temperature measurement errorin2℃or so under the fixed environment condition.My target is studying accuratemeasuring human body temperature distribution in my design, I use FLIRproduction named Photon320movement,it’s pixels is324x256,it consist of therefrigeration vanadium oxide focal plane array and output9frames per secondvideo signals,I also completed the related research of the infrared temperaturemeasurement system design based on FPGA and influence the temperaturemeasurement accuracy, this can lay the foundation to the next step thermal imagerproducts development that meet the application of measuring human bodytemperature distribution under the fixed environment. To complete the specific workas follows:Firstly, the secondary development of the infrared movement is mainly based onthe FPGA’S development, mainly complete the frame rate conversion and interfaceconversion. At first, I has completed the system hardware circuit principle diagram ofthe design work, draw the complete hardware circuit diagram.Then I used QuartusII9.0software tools to design a set of video processing software program.The softwareprogram mainly be used to make frame rate of video signal from9frames per secondup to25frames per second, and connect to the computer for processing and display. CVBS analog video signal which output to the monitor display is mainly used forsystem testing.Secondly, the development of PC software operation platform, mainly useVisual C++6.0’s MFC tools, the platform can real-time display signal transmissionover video images, also can control the opening and closing of movement. After thecalibration of thermal imager, the software platform can realtime display measuringgrey value and temperature value information.Thirdly, based on the application demand of each part of palm’stemperature measurement in fixed environment, I have studied measurementprecision of the established infrared thermal imager in this paper which influenced bythe distance, and tried to improve temperature measurement precision. Firstly, in thecertain environmental temperature and humidity conditions, I conducts theexperiments to research temperature measurement accuracy of different measurementdistance under one temperature measuring distance calibration, the result is that themeasuring accuracy is0.43℃, and the farther away from the calibration distancemeasuring, the accuracy is poorer. Secondly, I studies the temperature measurementaccuracy of different measurement distance calibrated afresh, measuring meanabsolute error can reach0.07℃by using this method, it provides a method to useinfrared thermal imager measure temperature distribution of object more precisely inthe fixed environment. The experiment also studied the linearity between with thethermal imager grey value and blackbody measurement temperature,and also studiedthe thermal imager preheat time effect on the stability of the thermal imagingmeasurement.