Micro shape and rough surface analysis by fringe projection

Abstract

A new microscopic fringe projection system is described. Projection of the grating and imaging of the fringes is accomplished by the same objective. The spectrum of the binary grating is spatially filtered and projected into the aperture with a lateral shift. This leads to telecentric projection and imaging under oblique incidence. Topographies of specularely as well as diffusely reflecting surfaces can be obtained. The measurement of rough, technical surfaces is demonstrated.