Method to reduce systematic, spatial high-frequency measurement errors occurring in optical co-ordinate measurement device; involves forming relative error function from reference image and scaling

摘要

The method involves determining a relative error function of a decoder according to a real image of an ideal reference object in the decoder in an area of the image that corresponds to a period (zeta p) of the phase pattern of a strip projector. The relative error function is scaled with respect to the phase axis of the relative error function to generate an absolute error function. A characteristic curve specific to the measurement system is determined to remove high frequency components of the error function. A real image of a desired object is substituted using a decoder image and the characteristic curve.