NAO VOLUME IV
Features and benefits of trivex include_____: - ✔️✔️superior optics, impact resistance,
ultra-light weight (all of the above)
Given a high plus or minus RX, which lens material would offer the best choice for
uniform density in a sunlens? - ✔️✔️cr-39 plastic and trivex
If a person has exposure to sunlight at least 2 hours or more during the day, their _____
- ✔️✔️Ability to adapt to night vision is compromised if they don't protect their eyes
from the sun exposure
The amount of reflection of each surface of CR-39 plastic lenses is approximately: -
✔️✔️4%
The absorption of light in lenses is classified by two variables. What are they? -
✔️✔️Tint and lens transmission
The denser the tint in a lens, the _____: - ✔️✔️Less transmission of light through the
lens
Standard transmission in sunlenses should range between: - ✔️✔️15% and 30%
A characteristic of a dark tinted glass lens with an RX of +4.00D sphere would b_____ -
✔️✔️Dark in the center and lighter on the edge
Although this may be the most popular color for sunlenses, it is not recommended for
patients with emerging cataracts: - ✔️✔️gray
_____ added to any color increases contrast: - ✔️✔️yellow
_____ is better than _____ for improving contrast: - ✔️✔️green
Glare is of more concern to which wearer? - ✔️✔️cataract patient
_____ are generally inorganic materials (metals or minerals) that are vacuum deposited
to add color on glass lenses to give a uniform density of color on the lenses: -
✔️✔️vacuum color coatings
Which company introduced CR-39 plastic lenses? - ✔️✔️PPG Industries
Features and benefits of trivex include_____: - ✔️✔️superior optics, impact resistance,
ultra-light weight (all of the above)
Given a high plus or minus RX, which lens material would offer the best choice for
uniform density in a sunlens? - ✔️✔️cr-39 plastic and trivex
If a person has exposure to sunlight at least 2 hours or more during the day, their _____
- ✔️✔️Ability to adapt to night vision is compromised if they don't protect their eyes
from the sun exposure
The amount of reflection of each surface of CR-39 plastic lenses is approximately: -
✔️✔️4%
The absorption of light in lenses is classified by two variables. What are they? -
✔️✔️Tint and lens transmission
The denser the tint in a lens, the _____: - ✔️✔️Less transmission of light through the
lens
Standard transmission in sunlenses should range between: - ✔️✔️15% and 30%
A characteristic of a dark tinted glass lens with an RX of +4.00D sphere would b_____ -
✔️✔️Dark in the center and lighter on the edge
Although this may be the most popular color for sunlenses, it is not recommended for
patients with emerging cataracts: - ✔️✔️gray
_____ added to any color increases contrast: - ✔️✔️yellow
_____ is better than _____ for improving contrast: - ✔️✔️green
Glare is of more concern to which wearer? - ✔️✔️cataract patient
_____ are generally inorganic materials (metals or minerals) that are vacuum deposited
to add color on glass lenses to give a uniform density of color on the lenses: -
✔️✔️vacuum color coatings
Which company introduced CR-39 plastic lenses? - ✔️✔️PPG Industries
