Abstract: A method and apparatus is provided for high speed, non-contact method of measuring the 3-D coordinates of a dense grid of points on a surface, including high accuracy interpolation between grid points. A plurality of pulsed laser sub-projectors sequentially illuminates a plurality of discrete Gray code bar pattern transparencies carried on a spinning circular code disk to project high frame rate structured light. The structured light is reflected by the surface and recorded at high signal-to-noise ratio by a plurality of high frame rate digital cameras, then decoded and interpolated by electronic signal processing. A numerical formula is derived for numbers of equally spaced discrete code patterns on the code disk that allow each camera to receive pulses from all sub-projectors and all patterns at a constant frame rate. Methods to derive an extended complementary Gray code pattern sequence and to normalize measured signal amplitudes are presented.