entrance pupil meaning in English

的直径
前透光孔
入射光瞳
入瞳

Space optical system , especially space infrared optical system , cryogenic optical system and some huge space - based telescopes , all work in the environment where there is strong radiation ( such as sun etc . ) out of the field of the system . because of diffraction of the entrance pupil and diffuse scatter of all inner surfaces , the strong stray radiation will reach the detector of the system
空间光学系统，特别是空间红外光学系统、低温光学系统以及某些大型空间望远镜，都工作在系统视场外有强烈辐射源(如太阳等)的“恶劣”环境中，这些强烈杂光辐射经过光学系统孔径的衍射，以及结构与光学件表面的散射，到达系统像面形成杂光。