ABO NOCE Basic Opticianry Verification of Progressive Lenses 2

Question 1

When using a lensometer to verify a progressive lens, where should the distance power be measured?

Accepted Answer

Through the distance reference point (DRP) or distance zone

Answer

Distance power is verified through the distance reference point (DRP) or the distance zone of a progressive lens, not the geometric center.

Question 2

According to ANSI Z80.1 standards, what is the allowable tolerance for the add power of a progressive lens up to +4.00 D add?

Accepted Answer

+/- 0.25 D

Answer

ANSI Z80.1 allows a +/- 0.25 D tolerance for the add power on progressive lenses with adds up to +4.00 D.

Question 3

A patient complains of swimming or swaying when wearing new progressives. Which verification step should the optician prioritize?

Accepted Answer

Measuring the monocular PD at the fitting cross

Answer

Swimming or swaying is often caused by incorrect monocular PD placement; verifying the monocular PD at the fitting cross is the critical first check.

Question 4

What is the purpose of the prism reference point (PRP) on a progressive lens?

Accepted Answer

It is the point used to verify prescribed prism or confirm zero prism

Answer

The PRP is the standardized point on a progressive lens used to verify any prescribed prism or to confirm that unwanted prism is within tolerance.

Question 5

When verifying a progressive lens on a lensometer, the mire appears blurry or broken. What does this most likely indicate?

Accepted Answer

The lens is positioned in the intermediate or near zone rather than the distance zone

Answer

A broken or blurry mire in a lensometer usually indicates the lens is not positioned at the distance reference point and is instead in the progressive corridor or near zone.

ABO NOCE Basic Opticianry Practice Test

ABO NOCE Basic Opticianry Practice Test

ABO NOCE Basic Opticianry Verification of Progressive Lenses 2