基于互补色编码条纹投影的三维形貌测量方法

Three-Dimensional Shape Measurement Technique Based on Complementary Color-Encoded Fringe Projection

针对彩色编码条纹投影轮廓术中,被测物体表面颜色易与投影条纹颜色发生干扰的问题,提出了一种新的基于互补色编码条纹投影的三维测量方法。先后向被测物体投影一幅主彩色编码正弦条纹图和一幅与前者包含的彩色编码条纹颜色互为补色的彩色条纹图。利用两者颜色互补的特点,判断两幅图像中对应像素点的颜色状态来确定其在主彩色编码正弦条纹图中所属条纹的正确颜色,解决物体表面颜色干扰导致的条纹颜色误判问题,得到准确的彩色编码信息。采用傅里叶变换法获取主彩色编码正弦条纹图中包含的正弦条纹的包裹相位,基于彩色编码信息展开相位。实验表明,提出的方法能有效降低被测物体表面颜色对投影条纹颜色的干扰,可靠地实现物体的三维测量。

In order to measure the object with colorful surface whose surface color may interfere with the color distinguish of projected fringe pattern, a novel method based on complementary color-encoded fringe projection is proposed. Two fringe patterns are projected onto the object in sequence. The first frame is encoded in a hybrid way which is with the sinusoidal color fringe and with the color coding information. The second frame is other color fringe pattern whose color is the previous encoding color＇s complementary one in each according pixel. Based on the color complementary feature of the two patterns, the color information of each pixel in the captured color-encoded sinusoida[ fringe image can be established with the assistance of the complementary color pattern, so that the interference of object＇s color can be eliminated. Phase retrieval is done by the Fourier transform method applied to the sinusoidal fringe and unwrapped according to the color coding information. Experimental results show that the proposed technique is valid and can be applied to the measurement of colorful object.