orthograph

Our experiments show that the photogrammetry with digital camera has a better precision and the large scale topographic map and orthograph can be produced with it.

试验证明利用数码相机进行摄影测量精度很高，能够用来测制大比尺地形图和影像图。

The formula of the curve tangent slope at some peculiar point in the orthograph on the stereoscopic surface intersecting line and the method of making tangent are given as well.

本文过可展曲面微分不变量,导出可展面曲率线与曲率特征,并锥面和切线曲面为阐明这些特性几何意义。