Fringe Order Determination in Grating Projection Method and its Application to Shape Measurement of Lens Materials

Abstract

This paper describes a non-contact 3-D profile measurement of lens materials using a grating projection method in a practical application. To get a high accuracy, 1) phase shifting technique with a sinusoidal grating is used and 2) determination of the fringe order of projected grating using pattern is achieved by colored filters at the same time. The surface profile of a pressed lens material is measured to demonstrate the validity of this method.