When buying new prescription glasses, the frame you choose is important for both appearance and comfort, but the lens you choose impacts your vision and safety. So how do you know what type of lens is best for you? In this blog post we’ll talk about single vision lenses, bifocal lenses, multifocal lenses and what conditions these lenses are suitable for.
Single vision lenses
If you have myopia (short-sightedness) or hyperopia (long-sightedness) and you’re under the age of 40, you will most likely need single vision lenses. These are specifically designed to correct one field of vision (near or far) and are the most common and least expensive lens option.
Bifocal lenses and trifocals
If you are over 40, or have difficulty focusing at different distances, you may need glasses that correct near and distance vision. If this is the case, there are a few options available. Bifocals and trifocals are a versatile choice, allowing you to correct distance and near vision with one pair of prescription glasses.
Both bifocals and trifocals have separate sections for near and distance correction, with visible lines between each section. This can be a drawback for some people, as the lines can create sudden changes in vision when you move your eye up and down. The trifocal also has a small section devoted to “intermediate” or arm’s length vision – good for computer monitors.
While most people these days choose the more advanced multifocal lenses, conventional bifocals and trifocals usually provide wider lens areas for near vision.
Advances in technology allowed for the creation of multifocal lenses, which offer similar fields of vision as bifocals or trifocals, but without the lines. Multifocal lenses, also known as progressive lenses, correct vision for near, far and intermediate distances and all points in between.
Transitions between the near, far and intermediate zones are much smoother in multifocal lenses than bifocals or trifocals.
Some people find it difficult to first adjust to Multifocal lenses. Read our tips for Getting Used To Multifocal Lenses.
Computer glasses are a variation of multifocal lenses that help to prevent eye strain and headaches for prolonged use of the computer. Computers are usually positioned in the intermediate (arm’s length) zone of vision, which may not be corrected by single vision lenses. Computer glasses correct near and intermediate distances, with a larger intermediate zone for more comfortable use at the computer. These glasses are generally only suitable for computer work and reading, they aren’t recommended for distance tasks or driving.
Along with the type of lens, there are a number of different coatings available to make your glasses more suitable for specific uses. For instance:
- Photochromic glasses or transition glasses darken when they come into contact with UV rays, eliminating the need for sunglasses in most situations. They return to being completely clear when indoors. The latest version of Transitions lenses, “Generation 8” was released on April 1 and boasts faster changes between dark & light, and darker tinting outdoors.
- Blue light glasses filter out blue light from screens, and for some people may help to minimise eye strain and fatigue from prolonged exposure to screens
- Anti-reflective coating reduces reflections off the lens surface and allows more visible light to enter the eye, particularly for driving at night. They also look great!
At Custom EyeCare, we use quality optical lenses and frames, from a 100% Australian lens laboratory, giving you clearer and more comfortable vision. Read Why Should You Buy Your Glasses From Custom EyeCare and check out some of our prescription glasses frames.
If you need to update your glasses prescription or it’s time for your yearly eye examination, book an appointment with Custom EyeCare today.