Wavefront metrology sensor and mask thereof, method for optimizing mask and associated apparatus

A wavefront sensor for measuring a wavefront of radiation is disclosed. The wavefront sensor includes a mask including a pattern located in a path of the radiation so as to interact with the radiation. The radiation impinging on the mask forms a radiation detection pattern on a radiation detector located behind the mask, and the pattern of the mask is designed based at least in part on requirements of the radiation detection pattern. 披露了一种用于测量辐射的波前的波前传感器。所述波前传感器包括掩模，所述掩模包括位于所述辐射的路径中以便与所述辐射相互作用的图案。照射于所述掩模上的所述辐射在位于所述掩模之后的辐射检测器上形成辐射检测图案，并且所述掩模的所述图案是至少部分地基于所述辐射检测图案的要求而被设计的。