entrance pupil
noun
The aperture through which light enters an optical system; the image of the aperture stop as viewed from the front; specifically the image of pupil of the eye as seen from outside the eye; the pupil itself.
- The entrance pupil determines the cone of light entering an optical system..
Origin
Late 19th century.
- roll-bearer
- roll boiling
- roll cage
- roll call
- roll-call analysis
- roll-calling
- roll-call vote
- roll carriage
- roll cast
- roll casting
- roll cloud
- roll collar
- roll-down
- roll-down table
- rolled asphalt
- rolled-down
- rolled gold
- rolled-in
- rolled into one
- rolled-neck
- rolled oats
- rolled-out
- rolled-up
- Rollei
- Rolleiflex