Zheng Yi, Yang Mu, Liu Zheng-Hao, Xu Jin-Shi, Li Chuan-Feng, Guo Guang-Can
Opt Lett. 2022 Jun 1;47(11):2734-2737. doi: 10.1364/OL.460873.
The weak measurement wavefront sensor detects the phase gradient of light like the Shack-Hartmann sensor does. However, the use of one thin birefringent crystal to displace light beams results in a wavelength-dependent phase difference between the two polarization components, which limits the practical application. Use of a Savart plate, which consists of two such crystals, can compensate for the phase difference and realize achromatic wavefront sensing when combined with an achromatic retarder. We discuss the spatial resolution of the sensor and experimentally reconstruct a wavefront modulated by a pattern. Then we obtain the Zernike coefficients with three different wavelengths before and after modulation. Our work makes this new wavefront sensor more applicable to actual tasks like biomedical imaging.
弱测量波前传感器像夏克-哈特曼传感器一样检测光的相位梯度。然而，使用一块薄双折射晶体来使光束发生位移会导致两个偏振分量之间产生与波长相关的相位差，这限制了其实际应用。使用由两块这样的晶体组成的萨伐尔板，并与消色差延迟器相结合，可以补偿相位差并实现消色差波前传感。我们讨论了该传感器的空间分辨率，并通过实验重建了由图案调制的波前。然后我们在调制前后分别获得了三种不同波长下的泽尼克系数。我们的工作使这种新型波前传感器更适用于生物医学成像等实际任务。
