Non-contact measurement of surface profile

摘要

A parallax method of wavelength labeling is based on optical triangulation. A complementary color pattern projected onto the surface is characterized by a continuous variation of the power ratio of two wavelength bands, and the profile can be measured at all points in the field of view. Shifts of the wavelength bands on separate detector arrays correspond to profile deviations. A signal processor calculates a normalized signal that is independent of surface reflectivity and roughness variations; the phase shift of this signal yields depth data from which the surface profile can be mapped.