Yang Yan, Kang Bo-seon
Department of Mechanical System Engineering, Chongqing Institute of Technology, China.
Appl Opt. 2008 Nov 10;47(32):5953-60. doi: 10.1364/ao.47.005953.
The feasibility and the accuracy of the correlation coefficient (CC) method for the determination of particle positions along the optical axis in digital particle holography were verified by validation experiments. A translation system capable of high precision was used to move the particle objects by exact known distances between several different positions. The particle positions along the optical axis were calculated by the CC method and compared with their exact values to obtain the errors of the focus plane determination. The tested particles were two-dimensional (2D) dots in a calibration target along with different-sized glass beads and droplets that reflected and caused a three-dimensional (3D) effect. The results show that the CC method can work well for both the 2D dots and the 3D particles. The effect of other particles on the focus plane determination was also investigated. The CC method can locate the focus plane of particles with high precision, regardless of the existence of other particles.
通过验证实验验证了相关系数（CC）法在数字粒子全息术中沿光轴确定粒子位置的可行性和准确性。使用能够实现高精度的平移系统，将粒子物体在几个不同位置之间以精确已知的距离移动。通过CC法计算沿光轴的粒子位置，并将其与精确值进行比较，以获得焦平面确定的误差。测试粒子包括校准靶中的二维（2D）点以及不同尺寸的玻璃珠和液滴，这些玻璃珠和液滴产生反射并造成三维（3D）效果。结果表明，CC法对2D点和3D粒子均能良好工作。还研究了其他粒子对焦平面确定的影响。无论其他粒子是否存在，CC法都能高精度地定位粒子的焦平面。
