Industrial development has brought increasing demand for 3D measurement systems. One of the modern and commonly used techniques consists of fringe projections cast by projector and captured by camera. It is distinguished by its speed and accuracy of capturing 3D images.
In order to improve its results it is necessary to perform calibration of the entire measurement system. Camera calibration is well-researched and explained process achieving excellent results. Projector calibration is regarded as the calibration of the reverse camera, which is not quite suitable because optical offset of the projector and causes inaccurate calibration. To achieve greater calibration accuracy most articles approach camera and projector as combined system which leads to more or less precise results from different calibration techniques. Calibration approaches are divided in to construction of lookup tables with corrections for each separate pixel and parametric distortion model which uses mathematical models of radial an tangential distortion to correct each pixel. Approaches differ in accuracy, speed and convenience of measurement and results or the type of additional equipment in the measurement system.
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