Zernike矩提高哈特曼波前传感器的鲁棒性

Improvement of the Robustness of Hartmann Wavefront Sensor by Using Zernike Moment

哈特曼波前传感器是自适应光学(AO)系统中常用的波前传感器件,噪声、器件装配误差常常影响其探测波前的能力和精度,进而影响整个系统对波前的实时校正。通过实验证明,引入数字图像处理中的矩技术,无需在硬件上对自适应光学系统进行修改,利用Zernike矩噪声不敏感、旋转不变等特性,对波前传感器CCD数据进行预处理,能够降低系统对噪声的敏感性,减小对器件装配精度的要求。

The Hartmann wavefront sensor is commonly used in adaptive optical （AO） system to measure the wavefront aberration. Noise and assembly errors decrease the accuracy of a Hartmann wavefront sensor, thus degrade the quality of the AO system. The moment theory, which has its origin in digital graphic discipline, is introduced into AO system. The Zernike moment is utilized as pre-processing filter because it is insensitive to noise and rotationally invariant. Hence the AO system becomes less sensitive to noise, and no high assembly precision is required.