1. The cornea provides a clear window in the eye to allow images to pass through to the image processing tissue, the retina.
2. The optic nerve is the information superhighway of the eye. It transmits the information the retina collects and sends it to the brain for processing.
3. The image must be brought to a point of focus (the lens of the eye or a camera is responsible for this), and the image must be brought to focus on a surface capable of capturing the image in a form that either is saved (such as the film of a camera) or instantly processed (such as the retina of the eye).
4. The focal length is found using the equation F = 1 / d , where F is the power of the lens and d is the focal distance in meters. Therefore, 4 = 1 /d . Solve for d and you have 0.25 meters or 25 centimeters.
5. Trifocals and progressives both have focal points for distance, intermediate, and near.
6. Lens
7. Astigmatism
8. Nearsighted (Myopia)
9. Plus power lens
10. -3.00 -1.00
×
180. 1) Add the sphere and cylinder together to get the new sphere. 2)
Change the sign of the cylinder. 3) The axis is 90 degrees away from the original axis.
11. Five times worse. A 100-size letter is five times larger than a 20-size letter.
12. No. Only magnifiers magnify. Despite what you may hear, there are no such things as
“magnifying glasses.” Reading glasses, or “magnifying glasses,” simply clarify reading material at a close distance, giving the illusion of a magnification effect.

1. See your optical manager.
2. Step 1) Place glasses on patient’s face. Step 2) Mark the location of the pupil with a
Sharpie pen. Step 3) Place the lens in the lensometer and read the prism amount.
3. 3.6 prism diopters Base-in. Prism = F
×
D, so in the right eye
Prism = 5
×
.3 = 1.5, and in the left eye, Prism = 7
×
.3 = 2.1.
With a displacement of the optical centers outward in each eye and a minus-power lens, this places the thick part of the lens, the base, inward relative to the pupil in each eye. The horizontal prism is additive, so
1.5 BI plus 2.1 BI gives a total of 3.6 prism diopters BI.
4. Using a lens clock to measure the base curve in more than one axis of the lens. If the curves are different, warpage is present.
5. +1.50 to +2.00
6. The brand so that you can select the appropriate template for marking power locations.
7. Lens clock
8. Identifies the pupil location.
1. Temple
2. Rounded edges, plastic to hide thick lens edge, small size
3. Rounded edges, rim all the way around the lens, small size
4. Weight of glasses
5. Safe and durable
6. Double bridge
7. A frame with a dark bridge
8. Frame PD
1. Adjust the frame.
2. Pupillary Distance (PD)

3. Measuring PD
4. c. The proposed working distance.
5. The lower eyelid.
6. The center of the pupil.
7. The three-point touch.
8. Adjust the left temple inward or the right temple outward.
9. 10 degrees.
10. Spread the nosepads, increase pantoscopic tilt, and decrease vertex distance.
11. Well-made measurements
1. Polycarbonate
2. Better vision without glare and better cosmetic appearance
3. Polycarbonate, as with most higher index lenses, have less light transmission and a higher
Abbe value (more aberration). An antireflective coating will both increase light transmission and reduce aberrations in these lenses.
4. 1.66
5. Aspheric
6. The flat aspheric lens will increase reflections.
7. If the specific gravity is higher in the higher index lens.
8. Add an antireflective coating.
9. A flatter lens causing lash-crash and greater reflections.
10. Tint and UV coatings
11. Reduces reflections off the dark surface
12. Advantages: The spot on the lens is in focus for every distance in space, and there are no lines as there are in bifocals and trifocals.
Disadvantages: Peripheral distortions and a smaller reading area than in conventional bifocals or trifocals.
1. Advantages of hard lenses: Best optical quality, long lasting Disadvantages of hard lenses:
Initial comfort, lacks disposability Advantages of soft lenses: Disposable, good initial comfort Disadvantages of soft lenses: Lack optical quality for irregular prescription
2. Removing a hard contact lens once you have visually verified that the lens is on the eye.

3. No. Cleaners remove debris, disinfectors kill germs.
4. Re-clean the lens at the end of every week. At the end of the month, replace the case. Reclean the lens again no more than forty-eight hours prior to lens wear.
5. Tyler’s Quarterly
1. “Film over eyes”; Dimness of colors; Blurry/Foggy vision; increased glare, especially at night.
2. Straight lines appear wavy; images disappear when focused upon; Blurry/Foggy vision.
3. Floaters
4. There are typically no symptoms in early-stage glaucoma.

1. 2 diopters of prescription difference between the two eyes.
2. Slab-off. Contact lenses, separate reading and distance glasses, or a high-places bifocal segment are other less frequent alternatives to slab-off.
3. Equalize the center thickness the best as possible, equalize the base curve the best as possible, steer the patient to a small frame, and order slab-off if the patient is to wear a bifocal.
4. Slab-off is placed on the most minus, or least plus, power lens.
5. The blur from the cataract can hide the blind spot from macular degeneration. Once the cataract is removed, the macular degeneration blind spot may become more pronounced.