Question

Difference between effective focal length and back focal length

Answer 1

Answer:

HEYY MATE..

the effective focal length EFL is the distance between the rear principal point P', and the rear focal point F' of the lens. The back focal length BFL is the distance between the rear vertex V' of the lens, and the rear focal point F'. ... Determining the distance between P' and V' is a bigger issue.

HOPE IT HELPS...❤..

Answer 2

Explanation:

The distance between pole to the focus of spherical mirror is focal length.