Structured Light 3-D Measurement Module and System for Illuminating an Area-under-test using a Fixed-pattern Optic

A surface measurement module for 3-D triangulation-based image acquisition of a surface-under-inspection and under observation by at least one camera. The module having: (a) a casing housing an optical system comprising a plurality of lens elements positioned between a fixed-pattern optic and a light source; (b) an output of said fixed-pattern optic comprising a multi-frequency pattern comprising a plurality of pixels representing at least a first and second superimposed sinusoid projected simultaneously, each of the sinusoids represented by the pixels having a unique temporal frequency and each of the pixels projected to satisfy(c) a shifting element to spatially shift said output of said fixed-pattern optic during projection onto the surface-under-inspection; and (d) a plurality of images captured of said output of said fixed-pattern optic during projection onto the surface-under-inspection are used for the image acquisition.