Research Of Wide Swath Imaging Technology Based On Area-array Detector Adopting Whiskbroom Scanning Mode

Under current international political situation, developing infrared imaging system with wide field of view(WFOV) and high resolution to obtain information about the global environment and national security is of great significance. However, limited by area-array size, the small imaging field of view(FOV) of single frame achieved by the area-array infrared detector which can realize high resolution detecting is unable to meet the need of WFOV in infrared imaging. Choosing area-array detector adopting whiskbroom scanning mode to carry through object space scanning along the wingspan direction is a feasible way to realize WFOV and high resolution infrared imaging in aerial remote sensing.Starting from the overall design and analysis of wide swath imaging system based on area-array detector adopting whiskbroom scanning mode, a in-depth study with the goal of obtaining WFOV and high resolution image with stabilized FOV and clear image quality was carried out on key technologies such as wide swath imaging technology based on area-array detector adopting whiskbroom scanning mode, image motion compensation technology and image stabilization technology employing compound platform. The research achievements are described as follows:(1) WFOV and high resolution imaging along the wingspan direction was realized by triggering area-array detector proceeding multiple exposure in the process of bi-directional whiskbroom scanning of the whole machine. In addition, with the precise and synchronous coordination of forward-motion compensation(FMC), images of each scanning line are perpendicular to flight direction.(2) An innovative image motion compensation technique based on real-time line of sight(LOS) tracking was proposed to solve the serious problem of image motion caused by bi-directional whiskbroom scanning of the whole machine along the wingspan direction. After FMC and the real-time, synchronous and high-frequency compensation of image motion originated from whiskbroom scanning along the wingspan direction, WFOV images with clear quality, rich target minutiae and high resolution was obtained.(3) An innovative image stabilization technology employing compound platform was proposed with the function of dual axis inertially stabilized platform(ISP) directly compound into the existing opto-mechanical structure which is applied for whiskbroom scanning. At the same time of realizing swath imaging adopting whiskbroom scanning mode with FMC, an ISP was also configured for the imaging device itself, guaranteeing LOS stabilization of the imaging system in inertial space.(4) WFOV and high resolution image with stabilized FOV and clear image quality was obtained by the developed prototyping system after aerial carrier flight simulation test in the laboratory and the outfield flight test respectively.