NOCE Ophthalmic Optics Questions and Answers

Question 1

A patient's prescription is -6.50 D sphere. The optical center (OC) is inadvertently placed 4 mm below the pupil center. How much prismatic effect does the patient experience, and in what direction?

Accepted Answer

2.6 Prism Diopters Base Up

Answer

2.6 Prism Diopters Base Down

Answer

1.63 Prism Diopters Base In

Answer

1.63 Prism Diopters Base Out

Question 2

A patient with a prescription of +8.00 D sphere was refracted at a vertex distance of 12 mm. If their new glasses are fit with a vertex distance of 8 mm, what is the compensated power that should be ordered?

Accepted Answer

+7.75 D

Answer

+8.25 D

Answer

+8.00 D

Answer

+7.50 D

Question 3

Which of the following lens materials has the highest Abbe value, resulting in the least amount of chromatic aberration?

Accepted Answer

Crown Glass

Answer

Polycarbonate

Answer

High-Index 1.74

Answer

Trivex

Question 4

A patient complains of objects appearing sharp in the center of their lenses but blurry and distorted towards the edges. This is a classic symptom of which type of lens aberration?

Accepted Answer

Spherical Aberration

Answer

Chromatic Aberration

Answer

Pincushion Distortion

Answer

Barrel Distortion

Question 5

To resolve 2.0Δ Base-Up and 3.0Δ Base-In prism in the right eye, the laboratory must grind a single resultant prism. What is the approximate magnitude and axis of this resultant prism?

Accepted Answer

3.6Δ axis 146

Answer

5.0Δ axis 056

Answer

3.6Δ axis 034

Answer

5.0Δ axis 124

Question 6

An optician is selecting a lens material for a high-power myopic prescription (-9.00 D). To achieve the thinnest and lightest possible lens, which of the following material characteristics is most important?

Accepted Answer

High Index of Refraction

Answer

Low Specific Gravity

Answer

High Abbe Value

Answer

Low UV Transmittance