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- Bifocals - Wikipedia
Bifocals are eyeglasses with two distinct optical powers correcting vision at both long and short distances Bifocals are commonly prescribed to people with presbyopia who also require a correction for myopia, hyperopia, and or astigmatism Benjamin Franklin is generally credited with the invention of bifocals
- Bifocal Lenses: What They Are, Who Needs Them, and More
Bifocal lenses offer two prescriptions in one pair of eyeglasses The top half corrects distance vision, and the bottom half corrects near vision The two sections are divided by a distinct visible line People with presbyopia (difficulty seeing close objects) are most commonly prescribed bifocals
- What Are Bifocals? How Do They Work? | Warby Parker
The top part of a bifocal lens corrects distance vision, while a smaller portion at the bottom of the lens corrects near vision When looking closely at bifocal lenses, you can see a line where these different viewing zones meet
- Bifocals and Trifocals - A Complete Guide - All About Vision
As a bifocal wearer drops his eyes downward to read, the eyes naturally seek out the near-vision portion of the lens Try these interactive Rx forms to learn what the measurements mean on your eyeglass prescription or contact lens prescription
- What Are Bifocals and What Are They Used For? | Glasses. com®
When you’re young, the natural lens inside your eyes is flexible It can easily shift focus so you can see clearly up close and far away As you get older, this lens becomes thicker and starts to harden This makes it less flexible, which affects your near vision
- Bifocal Contacts Lenses: How Do They Work? - GoodRx
Bifocal contacts combine up-close and distance vision prescriptions into a single lens That way you can see both near and far — without glasses A variety of bifocal and multifocal contact options are available You might need to try several types before you find a pair that works for you
- The Complete Guide to Bifocal Lenses
What are bifocal lenses? Bifocal lenses combine two optical powers in a single lens: one for distance vision and another most typically used for near vision Manufacturers refer to this visible demarcation as a segment line or optical discontinuity
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