欠采样干涉图最小二乘相位解包裹算法改进

数字全息的再现光场相位一般具有较高的空间变化频率,而目前CCD、CMOS的空间带宽积还很有限,容易产生欠采样并导致包裹相位中有大量不可靠数据点存在,给最小二乘相位解包裹带来困难.本文将剪切干涉原理引入到数字全息再现光场的重构中,通过改变再现光场相位梯度的计算方法减少欠采样的影响,对现有的最小二乘相位解包裹算法进行了改进...

An Improvement on the Least- squares Phase Unwrapping Algorithm for Undersampled Interferogram

In digital holography, the reconstructed optical field phase generally has high spatial variation frequency, however, the space-bandwidth product is so limited that it is easy to introduce undersampling and to cause the existence of massive unreliable data points in the wrapped phase, finally, it gives least- squares phase unwrapping algorithm a difficult. Noted that both of the holographic interferometry and the shearing interferometry are important means of optical measurement. From the principle of shearing interferometry, it only needs to make a certain shearing on optical field and then overlay the interference. So the existing least- squares phase unwrapping algorithm would be improved if this principle is introduced in the refactoring of digita holographic reconstructed optical field. The feasibility and validity of the new method are proved by the simulated calculation and experimental verification. And the result shows that the phase obtained by the new method is closer to the experiment value and so it has stronger resistance ability to undersampling than the conventional method.