The designing ideas and results of the Chang'e-2 lunar orbiter CCD stereo camera are described ; the tests and on-ground scanning imaging experiments are presented. Chang'e-2 lunar orbiter CCD stereo camera use linear pushbroom imaging modes in the same way as Chang'e-1 lunar orbiter. The difference between the two cameras is that Chang'e-2 camera has greatly higher technical requirement. The main aspect is that the GSD of Chang'e-1 camera is 120m, while the GSD of Chang'e-2 camera is 7m in 100km circular orbit and lm at near-moon-arc in 100km/15km elliptical orbit. The allowable exposure time decreases greatly because of the improvement of spatial resolution and the increase of orbiting speed caused by the decrease of the altitude of the orbit. The allowable maximum exposure time is only 0.6ms when imaging lunar Sinus Iridum with extremely low reflectivity, and the time is 4. 5ms when imaging in 100km circular orbit with nonsaturated signal intensity. The camera should not only meet the global imaging in 100km circular orbit but also meet the local imaging of lunar Sinus Iridum with lm GSD. So the camera needs a wide imaging dynamical range and very high detective sensitivity. So the design and manufacture of the camera are difficult. The actual results of design and test before launch indicate that Chang'e-2 lunar orbiter CCD stereo camera would well meet the mission requirement.%介绍了嫦娥二号卫星CCD立体相机的设计思想与结果、发射前检测与地面推扫成像试验.嫦娥二号卫星CCD立体相机仍采用与嫦娥一号相同的线阵推扫成像模式,但嫦娥二号卫星CCD立体相机的技术指标要求大幅度提高,主要表现为地元分辨率由嫦娥一号的120m提高为嫦娥二号在100km圆轨上优于7m与在100km/15km椭圆轨道近月弧段优于1m.地元分辨率提高,加之轨道降低造成地速增大,致使在100km/15km椭圆轨道上对虹湾极低反射率的月面成像时最长曝光时间不能超过0.6ms.同时又要求相机在100km圆轨上曝光时间为4.5ms时不产生饱和,即CCD立体相机既要满足100km圆轨的全月面立体成像,同时又要满足在100km/15km椭圆轨道上1m成像分辨率的局域高精细探测,从而要求扩大相机的动态范围以及提高探测灵敏度,这些都使嫦娥二号CCD相机的设计、研制难度大幅增加.实际设计与发射前检测表明,嫦娥二号卫星CCD立体相机很好地满足了任务要求.
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