What are the lens options for my glasses?
Prescription glasses are not just a fashion accessory; they are essential for many of us, enabling us to see the world around us with more clarity. The core component of any pair of glasses is the lenses, which correct all kinds of vision issues. However, not all lenses are created equal, with each type designed to correct a certain issue.
Single Vision Lenses
Single vision lenses are the most commonly prescribed lenses and correct one field of vision: either distance, intermediate (for computer use) or near (for reading). These lenses will contain the same prescription power across the whole lens. For example, if you're nearsighted (myopic), single-vision lenses help you see objects far away or if you're farsighted (hypermetropic) they help you to see close-up objects clearer.
The name really says it all. Bifocal lenses are designed to provide clear vision for two different distances. These lenses are split into two parts: the top part for viewing objects at a distance, and a smaller lower segment, the reading segment, for near-vision tasks like reading. Bifocal lenses are usually recommended for people over 40 years of age suffering from presbyopia, an age-related vision problem that is quite common where the eye's lens loses its ability to focus on nearby objects.
Varifocal, progressive or multifocal lenses provide a very easy transition between different fields of vision: distance, intermediate and near. Unlike the above-described bifocal lenses, which come with a visible line separating the two vision fields, progressive lenses have no lines of separation. The top part of the lens helps with distance vision, the middle part for intermediate vision and the lower part for near vision. You can really shift your vision between different distances quite smoothly with these lenses if you need to.
Occupational lenses are specially designed for specific job occupations or tasks that require unique requirements in terms of vision. For example, computer or office lenses aim to help with intermediate and near working vision, so that the user has clear and comfortable vision for computer use or desk work. On the other hand, a pilot could have lenses customised to see clearly at very long distances and short distances too for all the necessary tasks he or she would need to perform in the cockpit.
Unlike any of the lenses we have gone through above that have a spherical surface, aspheric lenses have a more complex surface curvature. This unique design helps aspheric lenses to be thinner / flatter than any other lenses reducing distortion and giving the user a wider field of view. They are really helpful when it comes to individuals with high prescriptions, they are much lighter in weight, and are quite stylish, especially when coupled with large frames.
Choosing the right type of lenses for your glasses can make a massive improvement in your visual comfort and performance. But as always, you need to consider your lifestyle and your visual needs, work requirements and personal comfort when choosing your lenses. Whether it's single vision, bifocal, progressive, occupational, or aspheric lenses, your optometrist will help decide which is the right one for your needs. The perfect pair of glasses doesn’t only help with your vision but also with your life quality.
Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 7 Sep 2023, Last modified: 10 Oct 2023