RT Journal Article T1 Flexible calibration procedure for fringe projection profilometry A1 Quiroga Mellado, Juan Antonio A1 Vargas Balbuena, Javier A1 Terrón López, M. José AB A novel calibration method for whole field three-dimensional shape measurement by means of fringe projection is presented. Standard calibration techniques, polynomial- and model-based, have practical limitations such as the difficulty of measuring large fields of view, the need to use precise z stages, and bad calibration results due to inaccurate calibration points. The proposed calibration procedure is a mixture of the two main standard techniques, sharing their benefits and avoiding their main problems. In the proposed method, an absolute phase is projected over marked planes placed at unknown positions. The corresponding absolute phase and marks positions are recovered for each plane location. Using Zhang's calibration method, internal camera parameters (also called intrinsic parameters) and the spatial position for each plane are computed. Later on, a polynomial fit of depth with respect to the phase is performed. To obtain the absolute position of an object point, the depth coordinate is obtained by means of the polynomial calibration and its absolute phase. Then the lateral coordinates are computed from the depth, the internal parameters, and the pixel coordinates of the imaged point. Experimental results comparing the proposed method with the standard polynomial- based calibration are shown, demonstrating the feasibility of the proposed technique. PB Spie-Soc Photo-Optical Instrumentation Engineers SN 0091-3286 YR 2007 FD 2007-02 LK https://hdl.handle.net/20.500.14352/50786 UL https://hdl.handle.net/20.500.14352/50786 NO © 2007 Society of Photo-Optical Instrumentation Engineers. DS Docta Complutense RD 23 jul 2024