COA Flashcards - Lensometry 3% of exam
0
Q
When recording prism in a spectacle Rx, what does the abbreviation BO stand for?
A
Base out
1
Q
What is the name of the instrument used to neutralize lenses?
A
Lensometer (Lensmeter)
2
Q
What is determined by focusing the thin lines in a manual lensometer?
A
The sphere of the spectacle Rx is determined by the thin lines.
3
Q
What is the first step in performing lensometry?
A
Focus the eyepiece
4
Q
If you cannot center the thick and thin lines in the lensometer, the lens has _____.
A
Ground-in prism
5
Q
Each black ring seen in the lensometer eyepiece reticle measures how much prism?
A
1 diopter for each ring
6
Q
When performing lensometry, what is indicated if both thin and wide lines are in focus at the same time?
A
The lens is spherical
