Bifocal lenses are eyeglass lenses that contain two different prescriptions for correcting both near and far vision in one lens. The upper part of the lens is designed for distance vision, while the lower part is intended for near vision.
Bifocal lenses are used to correct presbyopia, a common age-related vision condition that occurs when the eye’s natural lens becomes less flexible, making it harder to focus on close objects.
Bifocal lenses can be made from a variety of materials, including
- glass,
- plastic
- polycarbonate,
They can be incorporated into various types of eyeglass frames, including full frames, half-frames, and rimless frames.
Here are some common types of bifocal lenses:
- Flat-top bifocal lenses: Also known as D-segment lenses, they have a distinct visible line that separates the distance and reading portions of the lens.
- Round segment bifocal lenses: These lenses have a rounded segment in the lower part of the lens that is used for reading
- Executive bifocal lenses: These lenses have a wider intermediate zone for computer work and a smaller reading area at the bottom.
- Progressive bifocal lenses: These lenses have no visible lines and gradually change in prescription from top to bottom, providing a smooth transition from distance to reading vision.
It’s important to consult with your eye doctor to determine which type of bifocal lens is best for your specific vision needs.
