Practice Test GeeksABO - American Board of Optometry Practice Test
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Optics & Lens Design Flashcards

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

Read the first 6 Optics & Lens Design flashcards as text

  1. What is the vergence formula used to find image vergence after a lens?

    Answer: L' = L + F

    The vergence formula states that image vergence equals object vergence plus lens power.

  2. A lens with a power of +5.00 D has a focal length of:

    Answer: 20 cm

    Focal length = 1/power, so 1/5 = 0.20 m = 20 cm.

  3. Which lens type is used to correct myopia?

    Answer: Concave (minus)

    Concave minus lenses diverge light to shift the focal point back onto the retina in myopic eyes.

  4. The approximate index of refraction of standard crown glass is:

    Answer: 1.52

    Standard crown glass has a refractive index of approximately 1.523, making it the traditional ophthalmic lens baseline.

  5. A higher Abbe value (V-number) in a lens material indicates:

    Answer: Less chromatic aberration

    A higher Abbe value means less dispersion of light into its component colors, resulting in less chromatic aberration.

  6. The base curve of a spectacle lens primarily affects:

    Answer: Cosmetic appearance and peripheral optics

    The base curve selection affects both the cosmetic profile and peripheral optical performance of spectacle lenses.