ABO NOCE Basic Opticianry Trivia 5

Question 1

What is the Prentice Rule formula used to calculate prism in opticianry?

Accepted Answer

Prism (Δ) = Power (D) × Decentration (cm)

Answer

Prentice's Rule states that prism (in prism diopters) equals the lens power (in diopters) multiplied by the decentration (in centimeters).

Question 2

Which segment style bifocal provides the widest near reading area?

Accepted Answer

Executive (E-style) bifocal

Answer

The Executive (E-style or Franklin-style) bifocal has a full-width segment that spans the entire lens width, providing the widest near zone.

Question 3

What does 'photochromic' mean in the context of ophthalmic lenses?

Accepted Answer

The lens darkens in UV light and clears indoors

Answer

Photochromic lenses contain molecules that reversibly darken when exposed to UV radiation and return to a clear state when UV is removed indoors.

Question 4

In the ANSI Z80.1 standard, what is the tolerance for sphere power for a lens with a power of -4.00 D?

Accepted Answer

±0.12 D

Answer

ANSI Z80.1 allows ±0.12 D sphere power tolerance for lenses with powers between 0.00 and -6.50 D.

Question 5

A patient's near PD is 62 mm and distance PD is 66 mm. What is each eye's near monocular PD if the eyes converge symmetrically?

Accepted Answer

31 mm each

Answer

Near PD of 62 mm divided by 2 equals 31 mm per eye, representing symmetric convergence from distance to near.

ABO NOCE Basic Opticianry Practice Test