文摘
In phase-shifting moire9; profilometry, grid lines are projected onto an object, and the deformed projection is imaged onto a second grid to obtain moire9; fringes. Grid noise is removed by translating both grids simultaneously in their own plane, and fringe phase-shifts are obtained by changing the relative distance between the two grids. From three or more phase-shifted moire9; fringe patterns, object surface height is calculated on all pixel points of the camera which records the moire9; fringe patterns. Classically, translation of the grids is performed mechanically. Recently, we have introduced a method using two liquid crystal light modulators to perform high-resolution phase-shifting moire9; topography without any mechanically moving parts. We now describe, how this new method can be implemented using a low-cost consumer product LCD projector. We show how the different LCD panels can be addressed, and how fast grid noise averaging can be implemented using a standard computer graphics board. Resolution measurements and application examples are presented on objects of different sizes.