focal-ratio

focal-ratio什么意思,focal-ratio翻译

基本解释

网络: 焦比；焦距比；焦比大

例句

• Or, you can calculate the exit pupil by dividing the focal length of the eyepiece (in mm) by the focal ratio of the telescope.

  或者，你还可以将目镜的焦距除以望远镜的焦比来得到出瞳尺寸。

• If you know the focal ratio but not the focal length, you can calculate it: focal length is the aperture (in mm) times the focal ratio.

  如果你不知道焦距，只知道焦比（focalratio），你可以通过这样计算的得到焦距：孔径（单位是mm）乘以焦比就是焦距。