ABO PrActicAl exAm lAtest 2026 ActuAl QuestiOns
And VeriFied Answers (lAtest uPdAte) A+
GrAde 100% GuArAntee VeriFied By exPerts
Single Vision - Answer-corrects for one distance
Multifocal - Answer-Corrects with two or more prescriptions (or 'powers')
Bifocal - Answer-lens having two focus strengths
Trifocal - Answer-pertaining to having three focus strengths
Calculating Prismatic Effects - Answer-obtained at the center of an optical lens by
producing a difference in edge thickness, either by grinding the back surface at an
angle to the front surface during lens surfacing or, if the lens has sufficient power, de-
centering the optical center of the lens
Compounding Prism - Answer-BI & BI
BO & BO
BU & BD
Cancelling Prism - Answer-BI & BO
BD & BD
BU & BU
Prentice's Rule - Answer-P=hcm x D
P=amount of prism created
h= number of cm OC moved
cm= centimeters (convert to mm, divide by 10)
, D= power in meridian with error
Vertical Imbalance - Answer-The difference in vertical prism power at the reading
level in a pair of lenses.
OC Height's by lens - Answer-SV = 1/2 of B
Progressive = Fitting cross
FT = 5mm above segment
Vertex Compensation - Answer-A plus lens when moved farther from the eye gains in
plus power
Distance is 0 with CL because they are on the eye
Vertex compensation Formula - Answer-De= Dl/(1 + d xDl)
De= diopter effective value of error created
D/= lens power (given power)
d= amount in METERS lens moved from refracted position to position lens is worn
Keep sign for what it is (+/-)
- to d means moves away
Horizontal Centration - Answer-PD
Vertical Centration - Answer-OC
Horizontal & Vertical Centration Formula - Answer-Given PD/OC - Human PD/OC= mm
moved
Frame PD is found by adding A+DBL
Power in Oblique Meridians - Answer-Dt= (sina)²x Dc +Ds
Dt= Total Power we need
And VeriFied Answers (lAtest uPdAte) A+
GrAde 100% GuArAntee VeriFied By exPerts
Single Vision - Answer-corrects for one distance
Multifocal - Answer-Corrects with two or more prescriptions (or 'powers')
Bifocal - Answer-lens having two focus strengths
Trifocal - Answer-pertaining to having three focus strengths
Calculating Prismatic Effects - Answer-obtained at the center of an optical lens by
producing a difference in edge thickness, either by grinding the back surface at an
angle to the front surface during lens surfacing or, if the lens has sufficient power, de-
centering the optical center of the lens
Compounding Prism - Answer-BI & BI
BO & BO
BU & BD
Cancelling Prism - Answer-BI & BO
BD & BD
BU & BU
Prentice's Rule - Answer-P=hcm x D
P=amount of prism created
h= number of cm OC moved
cm= centimeters (convert to mm, divide by 10)
, D= power in meridian with error
Vertical Imbalance - Answer-The difference in vertical prism power at the reading
level in a pair of lenses.
OC Height's by lens - Answer-SV = 1/2 of B
Progressive = Fitting cross
FT = 5mm above segment
Vertex Compensation - Answer-A plus lens when moved farther from the eye gains in
plus power
Distance is 0 with CL because they are on the eye
Vertex compensation Formula - Answer-De= Dl/(1 + d xDl)
De= diopter effective value of error created
D/= lens power (given power)
d= amount in METERS lens moved from refracted position to position lens is worn
Keep sign for what it is (+/-)
- to d means moves away
Horizontal Centration - Answer-PD
Vertical Centration - Answer-OC
Horizontal & Vertical Centration Formula - Answer-Given PD/OC - Human PD/OC= mm
moved
Frame PD is found by adding A+DBL
Power in Oblique Meridians - Answer-Dt= (sina)²x Dc +Ds
Dt= Total Power we need
