长焦距离轴三反测绘相机的外场立体成像

Outdoor stereoscopic imaging of mapping camera with long focus off-axis three-mirror

在地面模拟了长焦距、宽视场离轴三反光学系统的在轨立体成像,通过对图像的数据处理和分析,验证了离轴三反测绘相机在轨立体成像的可行性。提出了长焦距离轴三反测绘相机外场立体成像的单点成像方法。在该方法中,单台离轴三反相机通过旋转转台对靶标成像,根据规划的相机交会角旋转靶标,并精确测量出靶标的旋转角度,通过靶标的旋转来模拟两线阵相机的相机夹角。在外场立体成像中,根据轨道高度、外场立体成像的物距及理论设计需达到的高程精度和平面精度设计地面靶标。最后,对成像方式进行处理,验证了离轴三反测绘相机立体成像的可行性;对提出的外方位元素、两相机最佳夹角的测量方法进行了精度分析。该单点成像方法具有实用价值,可用于长焦距离轴三反测绘相机在轨立体成像的可行性验证。

The stereo imaging of a long focus off-axis three-mirror optical system on orbit was simula- ted in a laboratory, and the imaging possibility of the system on orbit was verified by image processing and image analysis. A single point imaging method was proposed for the outdoor stereoscopic imaging of the long focus off-axis three-mirror mapping camera. In this method, the single cameras was used to image the target through rotating an experiment table. The target was rotated according to a planned camera rendezvous angle and the angle was measured exactly. Then, the intersection angle of the two line array cameras was simulated by rotating the target. In the outdoor stereoscopic imaging, the target was designed based on the orbital altitude, object distance, elevation accuracy and planned precision. Finally, the image methods were verified and the measuring accuracy for exterior orienta- tion elements and the angle between two cameras were analyzed. Obtained results demonstrate that the single point imaging method has practical values and can be used in the feasibility verification of stereoscopic imaging of long focu off-axis three-mirror cameras.