中国科学院光电技术研究所机构知识库

  在天文自适应光学中，观测条件是不断变化的。当观测条件良好时，高采样率的哈特曼波前传感器具有更高的测量精度；而当观测条件恶劣时，低采样率的哈特曼波前传感器才能实现对目标的有效探测。然而，经典的哈特曼波前传感器实现变采样率测量的途径还不多，且存在一些不足。经典的哈特曼波前传感器采用平面波进行标定，这不利于其实现变采样率测量。本文对采用球面波标定的哈特曼波前传感器（简称“球面哈特曼传感器”）展开了研究，并且提供一种实现变采样率的方案。

  本文对球面哈特曼传感器实现变采样率的诸多细节进行了讨论，分析了变采样率对球面哈特曼传感器的主要性能参数的影响，然后根据光波传播的角谱理论建立了球面哈特曼传感器的MATLAB数值仿真，并对球面哈特曼传感器的性能进行了讨论。最后，本文搭建了球面哈特曼传感器的简易实验平台，分别在强光环境和弱光环境下利用球面哈特曼传感器实现了变采样率测量。在强光环境下，球面哈特曼传感器的绝对测量精度（残差的RMS）优于1/25λ（λ =635nm），相对测量精度（残差的相对RMS）小于9%。在弱光环境下，球面哈特曼传感器通过降低采样率成功提高了测量精度，验证了球面哈特曼传感器可以通过变采样率提高对不同观测条件的适应能力。

In astronomical adaptive optics, the observation condition is constantly changing. Hartmann wavefront sensor of high pupil sampling has a higher measurement accuracy under good observation conditions. when the observation condition is poor, only Hartmann wavefront sensor of low pupil sampling can measure the target object effectively. However, there are not many methods to adjust pupil sampling with classic Hartmann wavefront sensor, and all current methods have some shortcomings. Classic Hartmann wavefront sensor is calibrated with plane waves, which is not conducive to adjust pupil sampling. In this paper, Hartmann wavefront sensor calibrated with spherical wave (spherical Hartmann sensor) is studied, and a method to adjust pupil sampling is proposed.

In this paper, the details of adjusting pupil sampling based on spherical Hartmann sensor are discussed, and the influence of variable pupil sampling on the main performance parameters of spherical Hartmann sensor is analyzed. Based on the angular spectrum theory of light wave propagation, the MATLAB numerical simulation of spherical Hartmann sensor is established. And the performance of spherical Hartmann sensor is discussed by the MATLAB numerical simulation. Finally, a simple experimental platform of spherical Hartmann sensor is built in this work. With the platform，the measurement of adjustable pupil sampling by spherical Hartmann sensor is conducted under both strong light environment and low light environment. Under the strong light environment, the absolute measurement accuracy (RMS of the residual) of spherical Hartmann sensor is better than 1/25λ (λ=635nm), and the relative measurement accuracy (relative RMS of the residual) is below 9%. Under the low light environment, the measurement accuracy of spherical Hartmann sensor is improved by reducing the pupil sampling. It is verified that spherical Hartmann sensor with adjustable pupil sampling has better adaptability to different observation conditions.