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

At the geometric center of the lens

Answer

At the prism reference point (PRP)

Answer

At the fitting cross

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

+/- 0.12 D

Answer

+/- 0.50 D

Answer

+/- 0.18 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

Checking the pantoscopic tilt of the frame

Answer

Verifying the corridor length matches the prescribed design

Answer

Confirming the seg height is marked correctly

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

It indicates where to measure the near addition power

Answer

It marks the optical center of the distance zone

Answer

It identifies the start of the corridor

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

The lens has too much cylinder power

Answer

The add power exceeds the prescription

Answer

The lens has a scratch affecting the reading

Question 6

A progressive lens is ordered with 2Δ base-in prism OD. During verification, no prism is detected at the PRP. What should the optician do?

Accepted Answer

Reject the lens and reorder with the correct prism

Answer

Accept the lens because prism in progressives is difficult to verify

Answer

Grind additional prism into the lens in-office

Answer

Move the measurement point and re-read

Question 7

Which tool is commonly used to physically locate and mark the fitting cross and reference points on a progressive lens before verification?

Accepted Answer

Progressive lens identifier/decoding kit or felt-tip marker with the lens chart

Answer

Geneva lens clock

Answer

Vertexometer

Answer

Distometer