bifocal


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Related to bifocal: bifocal glasses

bifocal

1. Optics having two different focuses
2. relating to a compound lens permitting near and distant vision
References in periodicals archive ?
Washington, Jan 12 (ANI): Bifocal glasses can prove effective in slowing down the progression of myopia in children with high rates of progression, according to a new study.
Traditional bifocal glasses have a divided lens with the bottom area adapted for close-up viewing.
Traditional bifocal spectacles have a divided lens with the bottom area adapted for close-up viewing.
A recent report highlighted the likelihood of inducing an exophoric shift with bifocals in myopic children and, therefore, compared the effects of prismatic bifocal lenses with single vision and bifocal lenses.
Due to the induced base down prismatic effect created by the top half of the bifocal segment, the use of different round segments tends to work better for hyperopic patients as the base down from the segment helps cancel some of the overall prismatic effect when combined with the base up of the lower half of the distance portion.
Caption: The Mad Scientist from Tactical Rx: Side-panel protection from sneaky sideways sunlight, plus an "inverted bifocal" for long and short focus.
They're also available in non-RX bifocals. In addition to the Hawk, the company recently added a variety of frame styles and all of them have UV400, impact-resistant polycarbonate, prescription-compatible lenses.
There are a lot in the market that claim to offer Progressive Lenses but fail to deliver on comfort and after-care support, sending many customers back to their old reading glasses or bifocal lenses.
Mplus resulted in significantly worse CDVA than low-add refractive-diffractive bifocal IOLs (WMD: 0.08, 95% CI: 0.06 to 0.10, P < 0.00001).
I personally had bifocal cataract implants placed into my eyes (Crystalens HD).
Thus, Hafed's team thinks of the 'lens' in the SC more as bifocal glasses.
To bring the reticle into sharp focus, the bifocal wearer has to view it through the lower portion of the eyeglasses, and that means raising or tilting one's head.