ABO Practical Exam Comprehensive Questions (Frequently Tested) with Verified Answers Graded A+

ABO Practical Exam Comprehensive
Questions (Frequently Tested) with
Verified Answers Graded A+
Cancelling effect- subtract prism amounts - Answer: BU/BU

BD/BD

BI/BO



Powers between 0.00 & +/- 3.00 - Answer: Read in 1/8 diopters

.12

.37

.62

.87



Lensometer is also referred to as - Answer: Lensmeter, focimeter, vertometer



To focus eyepiece - 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 - Answer: Axis must be @ 180°, if not, transpose rx.



P=hcmxd - Answer: Prentice rule

P(prism)

Hcm(amount moved)

, D(diopter)



BO/BO - Answer: Compounds- add



BI/BI - Answer: Compounds- add



BU/BD - Answer: Compounds- add



BU/BU - Answer: Cancels- subtract



BD/BD - Answer: Cancels- subtract



BI/BO - Answer: Cancels- subtract



Black numbers on lensometer power drum - Answer: (+)



Red numbers on lensometer power drum - Answer: (-)



When neutralizing, if you have a power that is in 1/8 diopters and need to subtract - Answer:
Add 1 to 1/8 amount

Ex. .12, you would need to subtract .13



Focus sphere lines first, if cylinder lines focus first - Answer: Rotate axis drum by 90°



When you have cylinder power, turn the power drum to - Answer: The high plus, then gradually
reduce power until one of the meridians comes into focus.