数字全息参数优化

西安科技大学 机械工程学院,陕西 西安 710054

数字全息; 重构距离; 参考光角度

Digital holography parameter optimization
WANG Xing,MA Hong-wei,WANG Dou-dou,DONG Ming,ZHANG Yi-shu,WANG Hao-tian

(College of Mechanical and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China)

digital holography; reconstruction distance; reference light angle

DOI: 10.13800/j.cnki.xakjdxxb.2017.0119

备注

为了提高数字全息图的质量,文中从菲涅尔衍射积分出发,从理论上分析重构距离对全息图质量的影响。采用重构图的平均梯度为判断重构距离的标准,并通过参数调整重构距离的精度,提出了自动调整重构距离的方法,并设计离轴数字全息光路对其进行实验。实验结果表明:该方法可以显著提高全息图的质量。其中为了避免物光受共轭物光与零级像的干扰,在衍射场宽度的基础上,建立了CCD平面、重建像与参考光方向的模型,通过分析参考光与各个坐标轴之间的角度,推导出参考光角度的公式,通过分析与实验表明公式对参考光角度的可控性。

In order to improve the quality of digital hologram,the paper theoretically analyzes the influence of reconstruction distance on the quality of hologram based on Fresnel diffraction.The average gradient of the reconstructed image is used as the standard to judge the reconstruction distance,and the precision of reconstruction distance is adjusted by parameters.A method of adjusting the reconstruction distance is proposed,and the experiment of off-axis digital holography is designed.The experimental results show that this method can improve the quality of hologram.In order to avoid the interference of the object light by the zero-order and twin-image,a model of the CCD plane,reconstructed image and the direction of the reference light is established on the basis of the diffraction field width.By analyzing the angle between the reference beam and each axis,a formula of the angle of the reference light is deduced.Experiments show the controllability of the formula to the angle of reference light.