CPOA Ophthalmic Optics 3

Question 1

What is the purpose of an anti-reflective (AR) coating on spectacle lenses?

Accepted Answer

To reduce surface reflections and improve light transmission

Answer

AR coatings reduce surface reflections through destructive interference, increasing the amount of light transmitted through the lens and reducing glare.

Question 2

Which lens design divides the lens into two zones — distance on top and near on the bottom — with a visible dividing line?

Accepted Answer

Bifocal lens

Answer

A bifocal lens has a visible flat-top or round segment for near vision at the bottom and the distance prescription in the main lens above.

Question 3

What does base curve refer to in ophthalmic lens fabrication?

Accepted Answer

The curve on the front surface of the lens

Answer

The base curve is the curvature of the front (convex) surface of a lens, which influences the overall form and optical performance of the finished lens.

Question 4

Polycarbonate lenses are preferred for children and safety eyewear primarily because of their:

Accepted Answer

Lightweight and high impact resistance

Answer

Polycarbonate is highly impact-resistant and lightweight, making it the preferred material for safety eyewear and children's glasses.

Question 5

A prism prescribed as '2Δ base up OD' would displace the image in which direction for the right eye?

Accepted Answer

Downward

Answer

Base-up prism displaces the image downward, which is used to correct hyperphoria (eye deviating upward).

(CPOA) Certified Paraoptometric Assistant Practice Test

(CPOA) Certified Paraoptometric Assistant Practice Test

CPOA Ophthalmic Optics 3