消色散光变图像的二元光学设计与制作方法

提出了一种实现消色散光变图像的二元光学方法.以不同取向的狭缝光阑作为目标物光场,采用迭代傅里叶变换算法计算得到具有定向衍射特性的二元位相结构,并作为光变图像的微结构.面向不同图形结构的光变图像,给出了两种不同的数据方案.利用自行研制的激光直写系统以逐图形方式和矢量化直写工作方式分别光刻不同结构的光变图像,位相结构的线宽为2 μm.实验结果表明,定向衍射二元光学位相结构具有消色散特征,且适合于热压复制工艺,为制造消色散光变图像提供了一种新方法.

Design and fabrication for Achromatic Optical Variable Device

The method of designing binary optical element (BOE) is proposed to realize Achromatic Optical Variable Device (AOVD). The distribution of confined slot was used as target object and then the binary phase structure was calculated by Iterative Fourier Algorithm (IFTA). The structure had directional diffractive character and acted as the cell of AOVD. Two different datum schemes were adopted to design AOVDs of different configurations. AOVD was fabricated by SVG-LDW04 lithography system in patternby-pattern mode and vector writing mode respectively. The minimum width of phase structure of AVOD is 2 μm and the photos of fabricated AVODs were also given. The results show that the directional diffractive binary phase structure was achromatic and apt for hot embossing and offers a new method for AVOD.