BBC Science Focus Magazine

HOW DO VARIFOCAL GLASSES WORK?

Varifocals are lenses that allow you to see close-up, far awaycompany in 1959. Modern varifocals combine different prescriptions within a single lens, usually with near vision at the bottom, distance vision at the top and intermediate vision in the middle. While in bifocal lenses, the change between the near vision and distance vision prescriptions is clear-cut, in varifocals, there's more of a smooth transition, which gives the wearer a more seamless viewing experience.

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