双波长数字全息法测量物体三维形貌

Measurement of Three-dimensional Morphology of Objects by Dual Wavelength Digital Holography

基于双波长数字全息术的物体三维形貌测量技术,提出双波长光学相位解包裹和数值相位解包裹相结合的三维形貌复原方法。首先分析了双波长数字离轴全息形貌测量的基本原理和数据处理方法,然后利用Matlab软件建立了数字全息成像数值仿真模型,分析了高斯噪声对相位解包裹精度的影响。研究结果表明,在双波长法相位解包裹的基础上,进一步进行数值解包裹,能够有效复原出待测物体的三维形貌,但是随着高斯噪声的增大,测量精度显著下降。

For the measurement of three-dimensional morphology of objects by dual wavelength digital holography, a three-dimensional topography measurement technique for objects based on dual-wavelength digital holography, a three-dimensional shape recovery method combining dual wavelength optical phase unwrapping and numerical phase unwrapping was proposed. Firstly, the basic principle and data processing method of the dual wavelength digital off-axis holographic topography measurement were analyzed. Then the numerical simulation model of digital holography was established by using MATLAB software, and the influence of Gauss noise on the phase unwrapping accuracy was analyzed. The results show that the topography of the object can be restored effectively by the numerical phase unwrapping on the basis of the phase unwrapping with the dual wavelength method, but the measurement accuracy decreases significantly with the increase of Gaussian noise.