ABO NOCE Basic Opticianry Ophthalmic Optics and Principles 2

Question 1

Which lens form has the same power on both surfaces but with one surface convex and the other concave?

Accepted Answer

Meniscus

Answer

Plano-convex

Answer

Biconvex

Answer

Biconcave

Question 2

What is the term for the bending of light as it passes from one medium to another of different optical density?

Accepted Answer

Refraction

Answer

Reflection

Answer

Diffraction

Answer

Dispersion

Question 3

If a lens has a back vertex power of +3.00 D and a front vertex power of +2.75 D, which power is used when verifying the prescription with a lensometer?

Accepted Answer

Back vertex power

Answer

Front vertex power

Answer

The average of both

Answer

Either power can be used

Question 4

What happens to the critical angle when light travels from glass (n=1.5) into air (n=1.0)?

Accepted Answer

It is approximately 41.8°

Answer

It increases as n increases

Answer

It equals 90°

Answer

No critical angle exists for this direction

Question 5

A prism with apex angle 10° and refractive index 1.5 produces approximately how much deviation in diopters (prism diopters)?

Accepted Answer

10Δ

Answer

5Δ

Answer

15Δ

Answer

20Δ

Question 6

What is the vergence of light rays that are parallel to the optical axis before entering a lens?

Accepted Answer

Zero vergence

Answer

Positive vergence

Answer

Negative vergence

Answer

Infinite vergence

Question 7

In ophthalmic optics, the term 'base curve' most commonly refers to which lens surface?

Accepted Answer

The front convex surface

Answer

The back concave surface

Answer

The optical center

Answer

The edge of the lens