Study On Infrared Dual Band Scene Simulation And Testing System

Infrared dual-band imaging system, with its all-weather environmental adaptationcapability, anti-jamming capability, and dual-band information complementingfeatures, has become a research focus in the field of infrared. In order to accuratelytest and evaluate the performance of the infrared dual-band imaging system, aDMD-based infrared dual-band scene simulator has been developed, the performanceof the infrared imaging system and the modulation transfer function (MTF) testmethods has also been studied by using the infrared optics and signal processingtheory. A system model-based testing algorithm of MTF and the software has beendeveloped, which is to achieve the simulation assessment and the rapid test of theMTF of the long-wave infrared system, the medium wave infrared system andlong-wave/medium wave dual-band system. The main research is as follows:1. An athermalized infrared dual-band scene projection and illumination opticsworking at3~5μm and8~12μm based on the digital micro-mirror device (DMD)has been designed by use of the wide band reflective nature of the DMD and theunique temperature and dispersion characteristics of the harmony diffractive lens. Theaberration characteristics and design methods of the projection optics used in infrareddual-band scene simulation have been discussed, the aberration correction problems of the telecentric projection system with a large relative aperture and the uniformlyilluminating of the DMD have also been addressed, which improved the resolutionand uniformity. The athermal design has improved the stability of the system.2. The spectrum analysis and linear systems theory has been used to study theoptical imaging. The sampling and interpolation of the sampled imaging system andthe envelope of the system output has been analyzed, the sampling-interpolationmodulation transfer function of the sampled imaging system has been solved. Thelinear model of the optical imaging system has been established in the spatial domain,so that the optical imaging system can be uniquely determined by the model structureand parameters.3. The MTF test method based on the linear system model has been developed,which solved the problems of large test errors in traditional methods in the case ofusing short data sequence. The method is applicable to the MTF test of the imagingsystem in the field test. The wavelet multi resolution analysis has been used to removethe trend in the image, to achieve the adaptive image non-uniformity correction,which addressed the suppression of noise in the field test.4. The MTF test software was developed in VC++6.0, using Microsoft's basicclass library (MFC) and Windows document/view application architecture with mixedprogramming language of VC++and MATLAB in the object-oriented manner. Thecooperation of scene simulator and software has achieved the simulation assessmentand the quick test of the MTF of the infrared dual-band imaging system.