ABO NOCE Basic Opticianry Ophthalmic Products and Materials Questions and Answers 4 — Questions and Answers
Question 1: Which type of progressive addition lens (PAL) design places the corridor in a more nasal position?
- Soft design PAL (Correct answer)
- Hard design PAL
- Compact design PAL
- Wide corridor PAL
Correct answer: Soft design PAL
Soft design PALs distribute power more gradually with the corridor positioned nasally, offering wider intermediate and near zones with less peripheral distortion.
Question 2: Which lens tint color is most effective at enhancing contrast for shooting sports or driving in overcast conditions?
- Yellow/amber (Correct answer)
- Gray
- Green
- Blue
Correct answer: Yellow/amber
Yellow and amber tints enhance contrast by filtering blue light and haze, making them ideal for low-light or overcast conditions.
Question 3: The term 'base curve' in lens manufacturing refers to:
- The curvature of the front surface of the lens (Correct answer)
- The optical center of the lens
- The thickest part of the lens blank
- The prism incorporated into the lens
Correct answer: The curvature of the front surface of the lens
The base curve is the curvature of the front (convex) surface of the lens and is used in the lens form equation to determine the back surface curve.
Question 4: A polarized lens provides superior glare protection compared to standard tinted lenses because it:
- Blocks horizontally polarized reflected light (Correct answer)
- Absorbs more total light
- Contains UV-blocking compounds
- Has a mirror outer coating
Correct answer: Blocks horizontally polarized reflected light
Polarized lenses block horizontally polarized light reflected from flat surfaces like water, roads, and snow, which is the primary source of blinding glare.
Question 5: Which standard governs the impact resistance requirements for dress (everyday) ophthalmic lenses in the United States?
- FDA 21 CFR 801.410 (Correct answer)
- ANSI Z87.1
- ISO 8624
- ANSI Z80.1
Correct answer: FDA 21 CFR 801.410
FDA regulation 21 CFR 801.410 requires that all dress ophthalmic lenses meet impact resistance standards tested by the drop ball method.
Question 6: What does a blue light blocking lens coating specifically target?
- Light in the 380-500nm wavelength range (Correct answer)
- Light in the 300-380nm wavelength range
- Light in the 500-600nm wavelength range
- Light in the 600-700nm wavelength range
Correct answer: Light in the 380-500nm wavelength range
Blue light blocking coatings target the 380-500nm visible light range (high-energy visible or HEV light), with particular focus around 400-450nm.
Question 7: A lens with a plus power in one meridian and minus power in a perpendicular meridian is called:
- Toric lens (Correct answer)
- Bifocal lens
- Prism lens
- Lenticular lens
Correct answer: Toric lens
A toric lens has different curvatures in two perpendicular meridians, producing different powers in each, which is used to correct astigmatism.
Which type of progressive addition lens (PAL) design places the corridor in a more nasal position?