摘要 |
Three-dimensional measurement of a surface of an object under inspection is performed by projecting a light pattern upon the surface, having a periodic, smoothly varying light intensity in the X direction and having a non-changeable intensity in the Y direction in the manner of a grid, and thereafter electronically producing a pair of stereo images of the surface so illuminated by a pair of CCD arrays; measuring the parallax phase offsets between correlated corresponding homologous points in the stereo images, and converting the resulting parallax data to an array of Z-depth data, indicative of the shape of the surface of the object. A single left and right stereo snapshot is simultaneously obtained, so that relative motion between the object and the field of view has no adverse effect on accurate measurement, and the solid state light detection arrays are fully offset in an outboard direction with respect to the principal optical viewing axes, so that a stereo-based distance is provided which may be maximized to obtain more accurate measurements.
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