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40 Cards in this Set

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Photokeratitis, pterygia, pingueculae, and climatic droplet keratopathy are all things that can occur due to what?
UV radiation
Transmission of a lens system=?
T1xT2xT3 (all multiplied)
Color tints:

1. What is best for a hunter/shooter?
2. What's best for driving in haze/fog?
3. What's best for a blast furnace worker?
4. What's best for a sales person who works in a cubicle and complains of the glare at their desk (probably from the fluorescent lighting)?
5. What's best for the person trying to hide their segmented bifocals?
1. yellow
2. amber/yellow
3. blue
4. pink (Soft lite)
5. pink
Color tints:

1. What tint has uniform absorption across the whole spectrum?
2. Which tints provide UV protection?
1. gray
2. brown (some selective UV protection) and yellow (excellent)
How do we minimize reflections from surfaces of glasses?
AR coating
The intensity of reflected light increases as the ________ increases.
index of refraction (ex: POLYCARB needs AR coating)
Is AR coating a "cure" for the multiple ring effect?
No (bc the light is coming thru the edge of the lens, not the front or back where AR is placed)
What Rx is the patient more likely to develop amblyopia:

One eye emmetropic, one hyperopic
One eye emmetropic, one eye myopic
One eye emmetropic, one eye hyperopic
What is slab off prism used to correct?
vertical prism (caused by anisometropic Rxs when looking down thru the glasses)
What image size difference causes the most frequent complaints of aniseikonia?

What are the top symptoms for those with aniseikonia?
1-2.5%

asthenopia and headaches
T or F: One of the most common complaints with aniseikonia is perceptual distortion of space.
F!!! last common symptom
T or F: spectacle mag is a monocular phenomenon
T
Spectacle magnification has what two components? What are the things we can change about each one? Which one do we end up changing (since the other gives minimal results)
shape factor: B.C. and thickness
power factor: vertex distance (back vertex power is a part of this but we can't change it!)

shape factor
Lenses designed to eliminate or minimize aniseikonia are called what?
Iseikonic or Eikonic lenses
T or F: Aniseikonia is a monocular phenomenon.
F binocular
Iseikonic lenses ____ the magnification of the more plus lens and _____ the mag of the more minus lens.
decrease (flatten b.c. and make it thinner); increase
_____________= magnification that results from decreasing the distance of the object from the eye.

How do you calculate it?
relative distance mag

if you bring print from 40cm to 10cm, 40/10= 4x RDM (and you need a +10D lens)
__________= increasing the size of an object without moving its position.

Is additional accommodation needed?
relative size mag; no
________= mag. from optical or electronic enlargement
projection mag.
____ mag.= produced by the optical system; size of an object with and without the optical system
angular mag.
A galilean telescope has a ____ image. A keplerian has a ___ image.
erect; inverted
T or F: a galilean telescope will be shorter than a keplerian for any given mag.
T (also lighter)
For an uncorrected myope, which telescope will give greater mag?

For an uncorrected hyperope, which telescope will have greater mag.?
keplerian

galilean
___________= a single plus lens held at the spectacle plane; used to compare devices
equivalent power
What's the primary goal of a microscopic lens?
to allow for RDM
With a telescope with reading cap, what determines the working distance?
the reading cap power
If you put the hand magnifier closer than the _______, accommodation must be used.
primary focal plane
T or F: a disadvantage of a paperweight magnifier is that it has relatively low mag.
T
To help ease computer vision syndrome, our eyes should be looking down how many degrees at the computer? How far away should the computer be?
10-20; 50-70cm
For computer vision syndrome:

1. fit segmented bifocals ___ than the normal limbal position
2. use PALs with ____ intermediate zones
3. use a bifocal with the top portion _____ Rx
1. higher
2. wider
3. intermediate
What characterizes:

1. a non-industrial eye injury?
2. an industrial eye injury?
1. large, slow moving object
2. objects less than 6mm with high velocity
What are the two most common causes of broken glasses?
rocks, sports
What sports are assoc with the most common causes of broken specs?
basketball, baseball
T or F: contacts are a universal solution for both hyperopes and myopes with high Rxs
T
High hyperopes have more ____ problems while high myopes have more ____ issues with their glasses.
functional; cosmetic
The high hyperope's glasses have ____ peripheral AND macular fields of view.

The high myope has ____ peripheral and macular fields of view.
decreased; increased
Why to high hyperopes get ring scotomas with their glasses?
the decrease in the macular FOV is greater than the decrease in peripheral FOV
What lens aberration do you get with high plus lenses? High Minus?
pincushion; barrell
Where should you decenter a high plus lens so the patient doesn't have to use so much convergence at near?
nasally (decrease the amount of BO)
A lenticular lens is used for high myopic and hyperopic Rxs. They are __ and ___ but sacrifice ___. What appearance do they give the wearer?
lighter and thinner; FOV; bullseye