光子学报, 2016, 45 (3): 0310002, 网络出版: 2016-04-01
用于绝对相位还原的对称式和非对称式二元结构光编码
Symmetric and Asymmetric Dual Structure Light Coding Methods for Absolute Phase Retrieval
阶梯相位 二元编码 相移法 三维测量 绝对相位 Stair phase Binary coding Phase-shift method Three-dimensional measurement Absolute phase
摘要
基于邻域分析的相移法不适合阶跃场景测量且往往会造成相位误差的积累,为此提出了用于获取绝对相位的对称式和非对称式二元阶梯相位结构光编码方法.两种方法编码图案不同,对称式编码方法编码图案黑白条纹的宽度相等,非对称式不等.通过投影多帧二元结构光编码图案,结合相移法相位提取公式获得阶梯相位.测量时,基于传统正弦条纹投影和相移法获得高准确度包裹相位,并用阶梯相位确定对应包裹相位的级次.根据级次直接进行相位展开,进而获得绝对相位.以量块作为测量对象,两种方法的测量均方根误差达到0.072 mm.两种方法均能够有效还原阶跃场景,实现三维重构.
Abstract
Phase-shift method based on domain analysis is not suitable for measuring step-changed object and always causes the accumulation of phase errors .Symmetric and asymmetric dual stair phase structure light coding methods for absolute phase retrieval were presented. The coding patterns of two methods are different. The width of the black and white fringes in symmetric coding patterns are equal,but not in asymmetric coding patterns. By the projection of binary coding structure light patterns, stair phase can be obtained with phase shift formula. During measurement ,on the basis of traditional sinusoidal fringe projection and phase shift method, high-precisionwrapped phaseis obtained. The stair phase can be used to determine corresponding ordersof wrapped phase.According to the order, the absolute phasecan be got. Gauge blocks are measured and root mean square error of two methods are 0.072mm.Both methods can effectively restore three-dimensional reconstruction for highly step-changed object.
熊义可, 张万祯, 杨松涛, 林斌. 用于绝对相位还原的对称式和非对称式二元结构光编码[J]. 光子学报, 2016, 45(3): 0310002. XIONG Yi-ke, ZHANG Wan-zhen, YANG Song-tao, LIN Bin. Symmetric and Asymmetric Dual Structure Light Coding Methods for Absolute Phase Retrieval[J]. ACTA PHOTONICA SINICA, 2016, 45(3): 0310002.