ABO Practical Exam Question and Answer
(2026/2027) | Simplified Review Guide |
100% Verified Answers
• Cancelling effect- subtract prism amounts . CORRECT ANSWER: BU/BU
BD/BD
BI/BO
• Powers between 0.00 & +/- 3.00 . CORRECT ANSWER: Read in 1/8 diopters
.12
.37
.62
.87
• Lensometer is also referred to as . CORRECT ANSWER: Lensmeter, focimeter,
vertometer
• To focus eyepiece . CORRECT ANSWER: 1) while turned off. Place white sheet of
paper against lens stop.
2) turn focus ring all the way counter clockwise,and then back clockwise until
sharp.
3) remove paper and turn lensometer on
4) move power drum to high plus, then turn away from you until sharp- should
land at 0.00.
, • To read HORIZONTAL prism . CORRECT ANSWER: Axis must be @ 180°, if not,
transpose rx.
• P=hcmxd . CORRECT ANSWER: Prentice rule
P(prism)
Hcm(amount moved)
D(diopter)
• BO/BO . CORRECT ANSWER: Compounds- add
• BI/BI . CORRECT ANSWER: Compounds- add
• BU/BD . CORRECT ANSWER: Compounds- add
• BU/BU . CORRECT ANSWER: Cancels- subtract
• BD/BD . CORRECT ANSWER: Cancels- subtract
• BI/BO . CORRECT ANSWER: Cancels- subtract
• Black numbers on lensometer power drum . CORRECT ANSWER: (+)
• Red numbers on lensometer power drum . CORRECT ANSWER: (-)
(2026/2027) | Simplified Review Guide |
100% Verified Answers
• Cancelling effect- subtract prism amounts . CORRECT ANSWER: BU/BU
BD/BD
BI/BO
• Powers between 0.00 & +/- 3.00 . CORRECT ANSWER: Read in 1/8 diopters
.12
.37
.62
.87
• Lensometer is also referred to as . CORRECT ANSWER: Lensmeter, focimeter,
vertometer
• To focus eyepiece . CORRECT ANSWER: 1) while turned off. Place white sheet of
paper against lens stop.
2) turn focus ring all the way counter clockwise,and then back clockwise until
sharp.
3) remove paper and turn lensometer on
4) move power drum to high plus, then turn away from you until sharp- should
land at 0.00.
, • To read HORIZONTAL prism . CORRECT ANSWER: Axis must be @ 180°, if not,
transpose rx.
• P=hcmxd . CORRECT ANSWER: Prentice rule
P(prism)
Hcm(amount moved)
D(diopter)
• BO/BO . CORRECT ANSWER: Compounds- add
• BI/BI . CORRECT ANSWER: Compounds- add
• BU/BD . CORRECT ANSWER: Compounds- add
• BU/BU . CORRECT ANSWER: Cancels- subtract
• BD/BD . CORRECT ANSWER: Cancels- subtract
• BI/BO . CORRECT ANSWER: Cancels- subtract
• Black numbers on lensometer power drum . CORRECT ANSWER: (+)
• Red numbers on lensometer power drum . CORRECT ANSWER: (-)