What is a Flat Top 28 Bifocal Or FT-28 Bifocal?

A Flat Top 28 (FT-28) bifocal is the most commonly used type of lined bifocal. The "Flat Top" refers to the shape of the near vision segment, which is flat across the top, and "28" indicates the width of the Horizontal line of the bifocal measurement in millimeters.
In the FT-28 bifocal lens, the upper portion of the lens corrects your distance vision. The lower part, or bifocal section, contains the reading section or near vision segment, a horizontal rectangular area with a flat top edge. The reading segment is often positioned slightly below the center of the lens.
When wearers look through the upper portion of the lens, they can focus on objects in the distance. Wearers then can look down and use the near vision segment to read or perform close-up tasks. It offers a clear separation between distance and near vision, making it easy for wearers to identify and use the right part of the lens for their desired focus. However, the visible line can be noticeable to others when looking at the wearer's glasses.

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