Research On Infrared Irradiance Measuring Instrument

Infrared imaging target / interference simulator is an important part of infrared homing weapon simulation system, its performance can be a direct impact on simulation accuracy. Therefore, in order to ensure its performance, the exit pupil irradiance value of it must be tested and verified. Infrared radiation measuring instrument is an important component for the infrared imaging target / interference simulator system, Mainly used to receive the exit pupil at the IR target / interference beam from the infrared imaging target / interference simulator, and measure its radiation intensity values.According to the measurement principle of infrared radiation intensity, we use the detector as the standard measurement method, to get the mathematical relationship between irradiance and voltage, so as to realize the measurement of irradiance. Infrared radiation measuring instrument uses infrared indium antimonide (InSb) detector to achieve the measurement. The whole system is divided into two parts, hardware and software. Through infrared imaging system to received infrared imaging target / interference simulator exit pupil at the IR target / interference beam, modulated by the chopper into a certain frequency of the alternating signal and image in the detector, then after a pre-amplifier and lock-in amplifier to amplify the signal gradually, and through the data acquisition card, to make the analog signal into a digital signal, and then use the computer to make data processing, and finally the results will be stored and displayed.We use LABVIEW to write calibration procedures, data processing and measurement procedures. Then basis on a detailed study of the method of calibration, using the calibration program to make a rigorous calibration of instruments, using the data processing procedures to get the relationship between instrument output voltage and incident irradiance, and ultimately complete the measurement procedure, the instrument can be used to make Irradiance measurement.This design of infrared radiation measuring instrument passed the final test, and the precision and range of its scope of work can be guaranteed, also it meet the 5% uncertainty of the technical indicators, and the measurement of exit pupil Irradiance value at infrared imaging target / interference simulator can be achieved as well.