trifocal

(redirected from trifocals)
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Related to trifocals: Bifocals, Progressive lenses

tri·fo·cal

(trī'fō-kăl),
Having three foci. See: trifocal lens.

trifocal

(trī-fō′kəl, trī′fō′-)
adj.
1. Having three focal lengths.
2. Having one section that corrects for distant vision, a second section that corrects for medium vision, and a third that corrects for near vision, as an eyeglass lens.
n.
1. A lens having three focal lengths.
2. trifocals Eyeglasses having trifocal lenses.

trifocal

1. Having three focal lengths.
2. Distance-viewing spectacles having additional segments for intermediate and close ranges.
References in periodicals archive ?
Critique: An inherently fascinating and thoroughly absorbing read from beginning to end, "Seeing the World Through Rose-Colored Trifocals: No-Nonsense Observations on Getting Older" is very highly recommended and certain to be an enduringly favorite acquisition for community library collections.
Beveridge said the glasses were good for people with presbyopia, an inability to focus, especially on items that are close, which is often addressed with bifocals or trifocals. Beveridge called the design "a good start," despite some lens aberrations and distortions.
Studies have suggested that older adults who wear multifocals (bifocals or trifocals) may be at higher risk of falls, particularly when they first start wearing them.
What should I do with it?" Jackson Pollock's reply: "Spill some more." * "Vincent, I think you cut yourself while shaving." Vincent: "No, my lobe just itched, and I forgot to clip my fingernails before scratching my ears." * "Hey, Pablo, you just painted that woman with three eyes!" Picasso's reply: "She wears trifocals." * "Leonardo, does Mona like what you're painting her to look like?" da Vinci's reply: "If she did, do you think she'd smile that way?" *
Glasses: frequency/ % covered Every 12 or 24 months-single vision, lined bi focals & lined trifocals all covered in full after any applicable co- pay (in-network only) Contacts: frequency/% covered Every 12 months -annual allowance of $120-150 Laser vision correction No benefits Vision Benefits of America 800-432-4955 x205 | www.visionbenefits.com Product Name: Group Vision Plann PPO Availability: All states Min.
Multiple-focal lenses, such as bi- and trifocals, can create problems with depth-perception and send you hurtling toward the pavement.
I am 55-years old, Wear trifocals, am blind in one eye and can't see out of the other and can consistently make 3" groups at 100 yards with open sights.
If you wear bifocals or trifocals, your monitor probably should be considerably lower than usual positions.
Even lenses that do correct the intermediate zone, such as trifocals and progressive lenses, have only a small portion for the intermediate area--not nearly Large enough for comfortable computer work.
Baby Boomers are sporting trifocals. Many Americans can't read (or, more specifically, can't read English).