ABO Practical Exam
Cancelling effect- subtract prism amounts - ANS BU/BU
BD/BD
BI/BO
Powers between 0.00 & +/- 3.00 - ANS Read in 1/8 diopters
.12
.37
.62
.87
Lensometer is also referred to as - ANS Lensmeter, focimeter, vertometer
To focus eyepiece - ANS 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 - ANS Axis must be @ 180°, if not, transpose rx.
P=hcm - ANS Prentice rule
P(prism)
Hcm(amount moved)
D(diopter)
BO/BO - ANS Compounds- add
BI/BI - ANS Compounds- add
BU/BD - ANS Compounds- add
BU/BU - ANS Cancels- subtract
BD/BD - ANS Cancels- subtract
BI/BO - ANS Cancels- subtract
Cancelling effect- subtract prism amounts - ANS BU/BU
BD/BD
BI/BO
Powers between 0.00 & +/- 3.00 - ANS Read in 1/8 diopters
.12
.37
.62
.87
Lensometer is also referred to as - ANS Lensmeter, focimeter, vertometer
To focus eyepiece - ANS 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 - ANS Axis must be @ 180°, if not, transpose rx.
P=hcm - ANS Prentice rule
P(prism)
Hcm(amount moved)
D(diopter)
BO/BO - ANS Compounds- add
BI/BI - ANS Compounds- add
BU/BD - ANS Compounds- add
BU/BU - ANS Cancels- subtract
BD/BD - ANS Cancels- subtract
BI/BO - ANS Cancels- subtract
