大口径非球面计算全息图检测系统

CGH testing system for large aspheric surface

为了精确地检测大口径非球面面形质量,将曲面圆形计算全息图与补偿镜相结合,应用于非球面折射式检测光学系统中。分析了曲面计算全息图的衍射特性,同时分别阐述了利用曲面计算全息图的这种衍射特性来检测凹非球面及凸非球面的基本原理和方法,给出了具体的设计实例。与传统的非球面检测光学系统相比较,该系统不仅简化了传统光学系统的装调过程,还可以大大降低计算全息图(CGH)与补偿镜的制作精度,减少制作成本。尤其是在凸非球面检测过程中,首次在实验技术方面提出了两步全孔径检测法和调整误差的旋转相减消除法,实验验证了该方法的有效性。

According to the diffractive properties of compute-generated holograms, they have been combined with the traditional compensator to test aspheric surface. Compared with the traditional testing method, these methods not only simplify the adjustment of the optical systems, but also decrease the fabrication accuracy of the computer-generated hologram. The principle of CGH testing for large aspheric surface is analyzed,and the optical design systems and experimental results were given. Furthermore, methods for decreasing the size of the center light spot of the interferogram were proposed to realize the full aperture test and to remove the errors included in the test results.