DMD芯片在光栅投影三维轮廓测量技术中的应用

光栅投影成像法经常用于物体的非接触形状测量和形变测量。通过莫尔相移法,可以实时获得物体表面的等高轮廓线。但是在测量高速运动物体三维轮廓图像时误差较大,因为相移法需要拍摄几张经过相移后的变形光栅。在加入了DMD芯片后,可以在CCD的一帧图像时间内完成所有的相移后变形光栅的图像拍摄,有效地降低了高速运动物体三维轮廓成像的误差。

Application of DMD in 3-D Profilometry Using Grating Projection

A grating projection imaging method is often used in non-contact shape and deformation measurement.By using moire topography,the equal-height or equal-displacement contour images of an object can be obtained in real time.However,more errors would be generated when the three dimensional (3-D)contour images of an object moving at a high speed are measured, because the phase-shifting moire method should capture several deformation grating images which have been phase-shifted.After a Digital Micro-mirror Device(DMD)is incorporated,the phase-shifting scanning moire method can obtain an equal-height or equal-displacement contour image within a frame time,and hence effectively reduce the imaging error of the 3-D contour of the object which is moving at high speed.