传统的衍射光学元件(DOE)设计方法只适用于单个波长，但在全息投影显示、彩色图像生成等领域中往往需要多个DOE，系统较为复杂，很大地限制其应用范围。提出了一种新的DOE设计方法，利用该方法设计所得的单个DOE可以在多个波长的入射光下实现特定光场的输出。针对每个输入波长分别设计对应的DOE，以最长波长的DOE高度作为初始高度，结合加工工艺限制对该高度进行优化，使得每个入射波长对应的单波长DOE高度分布和多波长DOE高度分布之间的等效误差总和最小。利用该方法设计了用于彩色图像生成的DOE，分析了相关参数的取值范围对衍射效率和均方根误差的影响，并在最佳取值范围内进行了相应的数值仿真，仿真结果证明了该方法的可行性。

Design method of traditional diffractive optical element (DOE) is only applicable to a single wavelength. But multiple DOEs are often required in the holographic projection display and color image generation, which is more complicated to greatly limit the application scope. A novel design method of DOE used for multi-wavelength simultaneity is present. The Gerchberg-Saxton (GS) algorithm is adopted to design individual DOE at every wavelength. And then individual DOE structure at the longest wavelength is regarded as the iterative side, in every pixel of which the integral 2π phase height is added. Structure compare the equivalent phase of the corresponding pixel with that of the individual structure at the other wavelengths. When squared distance is the least, the iteration is complete. This method is simulated and the parameters are analyzed by using Matlab. DOE structure is quantized to the 16- level, which validates the feasibility of this method in actual production.