其实，挡光板及其上的开孔都是不必要的；单单反射镜本身就可以起小孔的作用。

Actually, the mask and openings are not really necessary; the mirror alone could serve as aperture.

youdao

其实，挡光板及其上的开孔都是不必要的；单单反射镜本身就可以起小孔的作用。

Actually, the mask and openings are not really necessary; the mirror alone could serve as aperture.

youdao