NACOR EXAM QUESTIONS WITH
COMPLETE SOLUTIONS
What Measurement is Eye Size? - Correct Answers -Horizontal measurement across
the lens
What is the B or Depth of the frame? - Correct Answers -Vertical Measurement
What is the Bridge Size? - Correct Answers -DBL
What is the formula for the distance between centers? - Correct Answers -A + DBL
What is the formula for the effective diameter - Correct Answers -2x the longest radius
What is the formula for Lens/frame difference - Correct Answers -A – B
What is the formula for Monocular PD for segment inset - Correct Answers -1/2 DBC -
PD near
What is the formula for Seg drop or raise, segmented multifocal? - Correct Answers -
Seg height - B/2
What is the formula for Fitting cross drop or raise, progressives: Fitting cross height - B2
- Correct Answers -Fitting cross height - B/2
What is the formula for Binocular Decentration Per Lens - Correct Answers -((DBC-
Wearers PD)/2)
What is the formula for Monocular Decentration Per Lens? - Correct Answers -((DBC/2)
- monocular PD)
or
((A+DBL2) - monocular PD)
What is the formula for Vertical Centration? - Correct Answers -(MRP height) -(B/2)
What is the formula for Binocular PD for segment Inset? - Correct Answers -Distance
PD-(Near PD/2)
What is the formula for Binocular PD for total inset? - Correct Answers -((A+DBL)-Near
PD)/2
COMPLETE SOLUTIONS
What Measurement is Eye Size? - Correct Answers -Horizontal measurement across
the lens
What is the B or Depth of the frame? - Correct Answers -Vertical Measurement
What is the Bridge Size? - Correct Answers -DBL
What is the formula for the distance between centers? - Correct Answers -A + DBL
What is the formula for the effective diameter - Correct Answers -2x the longest radius
What is the formula for Lens/frame difference - Correct Answers -A – B
What is the formula for Monocular PD for segment inset - Correct Answers -1/2 DBC -
PD near
What is the formula for Seg drop or raise, segmented multifocal? - Correct Answers -
Seg height - B/2
What is the formula for Fitting cross drop or raise, progressives: Fitting cross height - B2
- Correct Answers -Fitting cross height - B/2
What is the formula for Binocular Decentration Per Lens - Correct Answers -((DBC-
Wearers PD)/2)
What is the formula for Monocular Decentration Per Lens? - Correct Answers -((DBC/2)
- monocular PD)
or
((A+DBL2) - monocular PD)
What is the formula for Vertical Centration? - Correct Answers -(MRP height) -(B/2)
What is the formula for Binocular PD for segment Inset? - Correct Answers -Distance
PD-(Near PD/2)
What is the formula for Binocular PD for total inset? - Correct Answers -((A+DBL)-Near
PD)/2