基于宽光谱相位差异技术的波前检测

Wavefront Testing Based on Broadband Phase Diversity Technology

阐述了基于相位差异(PD)的波前传感技术的基本原理,并将该技术的应用领域由单色光或准单色光拓展为宽光谱照明。在大量计算机模拟仿真的基础上,设计了宽光谱PD技术的验证实验。用积分球照明作为光源,在实验室搭建了某相机调制传递函数测试实验平台,利用宽光谱PD技术进行波前解算和最佳焦面位置的确定,并对所采集的图像进行复原处理。此外,针对某相机的外场成像实验所采集的图像,利用宽光谱PD技术进行解算,得到了相机成像时的波前像差。实验结果表明:利用宽光谱PD技术解算得到的波前与干涉检验结果的均方根(RMS)偏差小于0.03λ,解算得到的焦面位置与测试得到的理想焦面位置偏差小于0.03 mm,检测精度满足工程实际需求。

The basic principles of wavefront sensing based on phase diversity （PD） are introduced. And the phase diversity is extended from monochromatic or quasi-monochromatic light illumination to broadband spectrum light illumination. Based on lots of computer simulation and analysis, the validation experiment of broadband PD technology is designed. The integrating sphere is used as the light source, and the modulation transfer function （MTF） testing experiment of some optical system is established in the lab. The wavefront of optical system and the best position of focal plane are calculated by broadband PD technology, and the images collected are restored. Furthermore, the outfield imaging experiment is designed. The broadband PD is applied to solve the wavefront aberration according to the images collected. The result shows that the difference between wavefront aberration solved by broadband PD and the root mean square （RMS） of interferometric testing result is less than 0.032t, and the difference of focal plane position solved by PD and MTF testing is less than 0.03 mm. The testing precision of broadband PD satisfies the requirement of engineering.