两线阵CCD相机几何指标差异对立体测绘的影响

为了准确、全面地揭示相机几何指标在立体测绘中的误差传播规律,研究了两线阵CCD相机几何指标差异与定位准确度之间的关系.针对两线阵立体测绘特点,分析了影响测绘定位的几何指标差异参量.在前方空间交会地面点计算公式的基础上,推导并建立了两线阵相机定位准确度模型,据此研究了内方位元素标定误差间的几何指标差异对定位准确度的影响规律.结果表明:主点位置x方向误差间的差异对定位准确度影响显著,当其值从1 μm增至2.5 μm时,定位准确度明显下降了60％,焦距f误差间的差异对定位准确度的影响几乎可忽略,本文所建立的模型与相关研究结论对两线阵CCD相机指标的量化与优化设计具有重要指导意义.

Effects of Geometric Specification Difference on Stereoscopic Mapping for Dual-linear-array CCD Camera

To reveal the error propagation rules of camera geometric specification in stereoscopic mapping more accurately, the relationship between the mapping accuracy and specification difference parameters of dual-linear-array CCD camera is studied. Aiming at the characteristic of dual-linear-array stereoscopic mapping, effects of the geometric specification difference parameters on mapping positioning are analyzed. Based on the space forward intersection formula, the positioning accuracy (PA) model is established, and then the variations of PA with the difference between calibration errors of interior orientation elements are presented. The results show that the effect of the difference between principal point x errors on PA is obvious, and the PA rapidly decreases by 60% when the difference change increases to 2.5 μm from 1 μm. In addition, the effect of the difference between focus length f errors on PA can be almost neglected. The model and relevant conclusions have important guiding meaning for the optimization design and quantification of dual-linear-array CCD camera specification.