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17 Cards in this Set
- Front
- Back
Which material is known to have the best optical properties?
A. Plastic B. Polycarbonate C. Crown glass D. Trivex |
C. Crown glass
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Which material is known for its superior impact resistance?
A. Plastic B. Crown glass C. Polycarbonate D. High index material |
C. Polycarbonate
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AR coatings cause light incident upon the lens to be:
A. Reflected B. Enhanced C. Transmitted D. Absorbed |
C. Transmitted
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What lens treatment best reduces glare from water and road surfaces?
A. AR B. Photochromic C. Polarized D. Dark tint |
C. Polarized
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Which of the following lens materials requires a UV coating to protect from ultraviolet radiation?
A. Polycarbonate B. Trivex C. Plastic D. All of the above |
C. Plastic
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Multifocal lenses are generally used to correct for:
A. Amblyopia B. Presbyopia C. Myopia D. Disentery |
B. Presbyopia
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The process used to reduce the bottom thickness of a progressive lens is called:
A. Fining B. Slab off C. Prism thinning D. Degeneration |
C. Prism thinning
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A slab off is used to compensate for differences in induced prism between the eyes caused by:
A. Anisometropia B. Presbyopia C. Amblyopia D. Too much difference between the patient PD and the frame PD |
A. Anisometropia
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Cataract surgery removes the crystalline lens of the eye causing the patient to lose the ability to focus. This condition is known as:
A. Antimetropic B. Antimetropic C. Aphakic D. Presbyopic |
C. Aphakic
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The refractive index of CR-39 is:
A. 1.52 B. 1.5 C. 5.12 D. 3.25 |
B. 1.5
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Plastic lenses are made of a hard resin material known as:
A. Cellulose acetate C. CR-49 C. PMMA D. CR-39 |
D. CR-39
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It is generally accepted procedure to fit the top of the trifocal segment to the:
A. Edge of the lower lid margin B. Bottom edge of the pupil C. Upper edge of the pupil D. Upper lid margin |
B. Bottom edge of the pupil
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Multifocal height is usually determined by measuring from the:
A. Lower edge of the lens B. Lower edge of the frame C. Upper edge of the lens D. Upper edge of the frame |
A. Lower edge of the lens
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Trifocals are most generally prescribed when the patient is:
A.Has double vision B. A presbyope C. About 45 years old D. An advanced presbyope |
D. An advanced presbyope
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Bifocals are used to correct for a condition called:
A. Myopia B. Presbyopia C. Anisometropia D. Emmetropic |
B. Presbyopia
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Which one of the following lens materials is generally thought to provide the best impact resistance for children's eyewear?
A. Heat treated crown glass B. Polycarbonate C. CR-39 D. Chem |
B. Polycarbonate
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What is aphakia?
A. the presence of refractive error B. the presence of a cataract C. the absence of the crystalline lens D. the absence of accommodation |
C. the absence of the crystalline lens
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