A

David

Darling

eye relief

Optics showing eye relief and exit pupil.

Optics showing eye relief and exit pupil. 1 Real image. 2 Field diaphragm. 3 Eye relief. 4 Exit pupil.


Eye relief is the distance from the observer's cornea to the nearest optical surface of the eyepiece. This is the distance at which the entire (or largest) field of view is visible.