1994 年 60 巻 2 号 p. 215-219
Due to the difficulties of measuring technique for the whole spherical surface, a concrete three-dimensional verification is not yet developed. This article deals with calculation of the value of spherical form errors, that is sphericity. The iterative least squares method in which the problem is linearized, and the minimum zone method in which the downhill simplex method, one of the nonlinear optimization technique, is applied are considered. The data to be referred is not obtained by actual measurement of spherical surface but simulated by using surface harmonics (Laplace's spherical function) in a computer. Then, their application conditions are investigated. Furthermore, the roundness values of the spherical surface are compared with the sphericity by means of the present method of this article.