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Ophthalmic Products and Materials Flashcards

7 cards from real NOCE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Ophthalmic Products and Materials flashcards as text

  1. Which frame material is the MOST flexible and corrosion-resistant, commonly used in rimless and semi-rimless mountings?

    Answer: Titanium

    Titanium is extremely lightweight, highly corrosion-resistant, and strong enough for drill-mounted rimless frames that require durable thin mounting points.

  2. A patient asks about the difference between a gradient tint and a solid tint. The key difference is:

    Answer: Gradient tints transition from darker at the top to lighter at the bottom

    A gradient tint fades from a darker concentration at the top of the lens (blocking overhead glare) to a lighter or clear area at the bottom (for reading or near tasks).

  3. When comparing CR-39 to high-index 1.74 material, which statement is MOST accurate?

    Answer: High-index 1.74 produces thinner lenses but has more chromatic aberration

    High-index 1.74 produces thinner, lighter lenses for strong prescriptions but has a lower Abbe value (around 33) compared to CR-39 (Abbe ~58), meaning more chromatic aberration.

  4. Which ANSI standard specifies the minimum impact resistance requirements for dress eyewear sold in the United States?

    Answer: ANSI Z80.1

    ANSI Z80.1 covers requirements for prescription ophthalmic lenses including the drop-ball impact test that all dress eyewear lenses must pass before dispensing.

  5. A patient's AR-coated lenses show a persistent greenish or purplish residual reflection. This is MOST likely due to:

    Answer: The normal residual reflection color of AR coating design

    AR coatings are designed with a specific residual reflection color (often green or blue-violet) that results from the interference properties of the thin-film coating stack — this is normal and intentional.

  6. Which lens edge treatment is required when glazing drill-mounted (rimless) lenses to prevent cracking at the mounting holes?

    Answer: Beveling and polishing the hole edges

    Drill-mounted lenses require the drilled holes to be chamfered (beveled) and polished to remove sharp stress risers that would cause the lens to crack under the mounting hardware.

  7. What is the primary purpose of a lens's oleophobic coating?

    Answer: Repels oils and fingerprints from the lens surface

    Oleophobic coatings repel oils from skin and fingerprints, making lenses easier to clean and maintaining better optical clarity during wear.