Linear method for evaluation of radius of spherical surface from discrete set of data points

Our work deals with the problem of evaluation of the spherical surface parameters from the discrete set of measured data points. We propose a new linear method for determination of the center and the radius of curvature of the measured spherical surface. Such method can be used for evaluation of the measurements obtained from both contact and noncontact 3D coordinate measuring machines. We perform an analysis of the proposed sphere fitting method and we verify that the obtained results are comparable to results calculated using existing techniques. Finally, the proposed algorithm is implemented for evaluation of real measurements of spherical optical surfaces using the designed scanning chromatic confocal system.