基于波前编码技术的对数位相掩膜板设计

Design of a logarithmic phase plate based on wave-front coding

为了扩大成像的景深,深入研究了基于波前编码延长景深系统的理论基础与设计方法,以稳相法为近似依据得到对数位相掩膜板的数学模型。该模型通过设定目标函数,应用Hilbert空间角度衡量2个函数的近似程度,得到对数位相掩膜板的优化参数。并分析了使用对数位相掩膜板的图像系统MTF和光点列图,实验证明这种新方法具有保持离焦恒定、延长景深的作用。

For extending depth-of-field,the wave-front coding theory was studied and an approximate model of logarithmic phase plate based on the stationary phase method was obtained.By defining the angle in Hilbert space to measure the similarity between two objective functions,the optimum values of the logarithmic phase plate were obtained.The MTF and the spot diagrams of the image system with the logarithmic phase plate were analyzed.Experimental results demonstrate that the new approach can make the defocus invariable and extend the depth-of-filed.