Research On Large Dynamic Range Infrared Simulation System Based On DMD

Infrared simulation technology can produce infrared scene which can be used to effectively test the performance of infrared imaging system in the laboratory. The technology has become a research focus for its advantages of high efficiency, convenience, low consumption, and repeatability. In this paper, several kinds of infrared simulation are analyzed and compared. In order to meet the present infrared system’s high spatial resolution and high frame rate applications, the research of infrared scene simulation system based on DMD is carried out.DMD is an MEMS device with high resolution, high frame frequency, high stability, which is mainly used to modulate incident light and reflect image information. In this paper the working principle and method of DMD are deeply studied and several commonly used methods of gray-scale modulation are analyzed. The frame rate of 100 Hz and the projection of 10~12 bit gray scale images are the two key requirements in system design indices. For this indices three kinds of scheme are put forward---modified PWM modulation, integral time synchronization and DMD splicing modulation. The former two can provide the 10 bit gray image under the maximum of 120 Hz and the latter supports flexible design of stitching way and modulation method, according to the resolution of the image source.The system in this paper mainly includes optical system, image processing software and DMD control part in which the DMD control which using Discovery 4100 platform is the key. The operation of data loading, data clear and DMD reset are analyzed and the development of DMD electronic part is completed in this paper.Finally, the prototype of infrared simulation system is built and the legible and stable infrared gray image can be observed by the infrared thermal imager. According to the indices of system the results are analyzed and the performance of the system are verified.