基于计算全息的零位补偿干涉检测

Null Compensation Interference Detection Basedon Computer-Generated Hologram

光学面形的检测精度直接影响成像系统的性能,对基于计算全息的补偿干涉检测技术进行了研究,针对共轴计算全息的衍射波面在成像中心区域发生重叠,形成测试盲区这一问题,采用离轴计算设计方案对非球面的面形进行测量,检测方案采用分光路干涉结构,用离轴计算全息和会聚透镜组构成联合补偿器对波面进行零位补偿并分离衍射级次,完成非球面面形的干涉检测.结果表明,该方案能够消除测试盲区,同时测得全口径面形数据,并保持了良好的精度.

The testing accuracy of optical surface directly affects the performance of imaging system.In this paper,the compensation interference detection technology based on computer generated hologram is studied.Aiming at the problem that the diffraction wavefront of coaxial computer-generated hologram(CGH)overlaps in the imaging center area and forms the test blind area,the off-axis calculation design scheme is used to measure the aspheric surface,and the optical path interference structure is used in the detection scheme A joint compensator composed of off-axis computer-generated hologram and converging lens group is used to compensate the zero position of the wavefront and separate the diffraction order.The results show that the scheme can eliminate the test blind area and obtain the full aperture surface data with good accuracy.