针对多次曝光法制作集成衍射光学元件时存在的加工制作复杂,会引入较大的对位误差等问题,基于计算全息中的误差扩散编码原理及部分相干光成像理论,提出采用误差扩散编码方法来设计用于制作浮雕结构集成元件的编码掩模的新方法。给出了利用误差扩散法设计的色分离光栅光束采样光栅(CSG-BSG)集成元件编码掩模,模拟计算了经部分相干成像系统后的空间像光强分布,并与理想的集成元件面形进行了比较。结果表明,校正后均方差为7.5%,体积偏差为10.2%。

The multiple exposure method has been proposed to fabricate combined diffractive optical element,but the multiple etch processing is complex and large alignment error will be introduced. According to error-diffusion method in computer-generated hologram (CGH) and partial coherent imaging theory, a new method to design coding mask of profile-combined element with error-diffusion method is presented. The designed coding mask for color-separation grating and beam-sampling grating (CSG-BSG) combined optical element with error-diffusion method is illustrated , and the intensity distribution of the spatial image in partial coherent imaging system is simulated, compared with ideal combined element relief. It shows that mean-square error is 7.5% and volume error is 10.2% after correction.