CPOA Spectacle Dispensing 3

Question 1

What does the term 'optical center' of a lens refer to?

Accepted Answer

The point where light passes through without prismatic deviation

Answer

The optical center is the point on a lens through which light travels in a straight line without being bent by prism effect.

Question 2

Pantoscopic tilt refers to:

Accepted Answer

The downward tilt of the lens bottom relative to the top

Answer

Pantoscopic tilt is the angle at which the bottom of the frame tilts toward the face, typically 8–12 degrees for optimum optics.

Question 3

Which of the following best describes 'induced prism' in spectacle lenses?

Accepted Answer

Prismatic effect caused when the eye views through a point other than the optical center

Answer

Induced (unwanted) prism occurs when the pupil is decentered from the lens optical center, creating a prismatic shift per Prentice's Rule.

Question 4

A lens with a base curve of 6.00 D and a front surface power of +6.00 D has a back surface power of -2.00 D. What is the approximate total lens power?

Accepted Answer

+4.00 D

Answer

Approximate total power equals front surface plus back surface: +6.00 + (-2.00) = +4.00 D.

Question 5

Which adjustment corrects a frame that sits too low on the patient's face?

Accepted Answer

Close (narrow) the nose pads

Answer

Narrowing (closing) the nose pads raises the frame higher on the nose, lifting it to a better position.

(CPOA) Certified Paraoptometric Assistant Practice Test

(CPOA) Certified Paraoptometric Assistant Practice Test

CPOA Spectacle Dispensing 3