Unlike conventional methods,the extended scanning path can vary the number of scanning curves through one position according to the normalized length profile of a group of partitioning curves in a specified direction characterized by curves normal to each boundary and by curves starting or terminating within the surface.

The results of the investigation show that nonlinear prolonged surface can be obtained by curved scanning and obvious differences exist in forming results of circular scanning and linear scanning respectively.

Using Gaussian decomposion method, we analyze the characteristics of Z-scan curves for nonlocal nonlinear materials in this paper.

At last,starting rose scanning and the process is terminated until capturing beacon light.

This paper introduces the characteristics of scanning curved surfaces and proves that the present algorithm is correct and efficient for the computer aided surface modelling with B - Spline.