At Vitality Optical Care we offer the widest range of lenses from suppliers such as Kodak, Essilor, and Zeiss. A quality lens is essential to provide the maximum clarity of vision.
Single-vision lenses
Single vision lenses have one single prescription across their entire surface and are suitable for all scenarios, whether you need your glasses for driving, working or just reading. The lens material will influence the thickness and weight of your lenses, as will the size and shape of the spectacle frame you choose. There is a wide range of materials available to suit your prescription and lifestyle.
Varifocal or Progressive lenses
Eyes change throughout our lives, gradually losing the ability to focus on close objects. During our mid-forties, the lenses in our eyes become stiffer which eventually causes blurred vision. This is called Presbyopia. You’ll probably find yourself holding books, newspapers or product labels further away, or needing more light in order to read clearly.
If you are experiencing the symptoms of Presbyopia, there are three lens options:
- Single Vision Reading: good for near vision only. If you look up at a computer screen or across the room, your vision will blur while wearing these glasses.
- Bifocal: an older option wherein the lens is divided into two distinct sections for near and distance, but provides no correction for mid-distance.
- Varifocal: ideal for all distances, as the lens corrects near, distance and in-between vision.
We recommend varifocal lenses for:
- The convenience of having natural vision at all distances in one pair of glasses.
- Great cosmetic appearance with no visible line on the lens, unlike bifocal lenses.
A range of varifocal designs is available depending on your lifestyle and occupation. Modern lens technology means that there are many different designs and materials to choose from.
High-index and aspheric lenses
If you need high-powered lenses you can improve the weight or appearance of your glasses with special lens materials and designs. High-index materials and aspheric designs mean that lenses can now be made thinner, lighter and better-looking than traditional lens types.
High-index materials make lenses for short sight thinner, while aspheric designs that minimise the amount of material make lenses for long sight both thinner and lighter. There are four different refractive indexes in plastic lenses;
- 1.5
- 1.61
- 1.67
- 1.74
The higher the refractive index goes the thinner and lighter the lens will become. Glass also comes into to higher refractive indexes;
- 1.8
- 1.9
Prescription sunglasses (Tinted Lenses)
Whatever your prescription, it is important to protect your eyes against excessive ultraviolet (UV) radiation. Prescription sunglasses can be made with single-vision, bifocal or varifocal designs to offer the same standard of protection as non-prescription sunglasses.
Safety and sports glasses
Special lenses and frames incorporating eye protection are available for a variety of safety and recreational uses.
Anti-reflection coating
An anti-reflective coating allows for clearer vision by reducing reflections, allowing 99.8% of the light through the lens and ensuring distractions to your vision are minimal. Reducing reflected light is particularly helpful for computer users and for night driving. Anti-reflection coatings also improve the cosmetic appearance of your glasses.
Scratch-resistant / hard coating
Scratch-resistant coatings are available to protect against damage and prolong lens life.
Lens Materials
Cr39 – this is the most common type of material used. Almost all basic lenses are made from this. Cr39 is transparent and is almost completely opaque in the ultraviolet range. It has high abrasion resistance, in fact the highest abrasion/scratch resistance of any uncoated optical plastic.
Crown Glass – is a type of optical glass used in lenses and other optical components. Crown glass is very rarely used due to when shattering; it can easily cause injury to the eye. Generally, patients with a very high prescription are inclined to using this as it can come in higher refractive indexes than general plastics
Polycarbonate / Trivex – Polycarbonate and Trivex lenses are the lightest and most shatter-resistant, making them the best for impact protection. They are usually used for rimless or half-framed glasses. A trivex lens is almost guaranteed to never break
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