Our staff have been extensively trained to advise you on the best choice of lenses and coatings. These can have a huge effect on the final appearance of your spectacles - for instance, there are now thinner lenses for high prescriptions, and special coatings to reduce glare and light reflections. Both these lens options will enhance the natural look of your eyes and emphasise the fashion, rather than the medical, aspect of your frames. All our high quality lenses are available in glass, plastic or polycarbonate, and are produced by the best lens manufacturers, including Essilor and Zeiss.
Depending on your prescription requirements you can also choose from our range of single vision, bifocal or varifocal lenses. Depending on your life-style, you may also benefit from the various coatings, tints and lens upgrades that we have available, such as high index, aspheric, photochromic or polarised lenses with a range of tints and coatings to choose from.
Single Vision Lenses
The simplest form of spectacle or contact lens is the single-vision lens, made to a single prescription to correct a particular eyesight problem. Concave lenses are used to correct short sight and convex lenses to correct long sight. Concave lenses are generally thinner in the centre than they are at the edge and convex lenses are usually thinner at the edge than at the centre. The curvature of the lens, its thickness and weight will depend on the amount of long or short sight it is designed to correct. The lens material will also influence the thickness and weight of your lenses, as will the size and shape of the spectacle frame you choose. Traditionally, spectacle lenses were made of glass but most lenses are now lightweight plastic and there is a wide range of materials available to suit your prescription and lifestyle.
Bifocal lenses contain two optical corrections with a distinct dividing line between the two parts. The most common use of bifocals is for people who have become presbyopic and need a different prescription for close work. The upper part of the lens corrects distance vision and the lower half is for near vision. Trifocals are also available that have three sections and incorporate a correction for intermediate vision. Bifocals and trifocals come in a range of designs but nowadays varifocal lenses are much more likely to be prescribed.
Varifocal lenses, also known as progressive lenses, are used for correcting presbyopia but unlike bifocal lenses have no visible dividing lines between the different corrections. Instead they have a graduated section in which the power of the lens progresses smoothly from one prescription to the other, allowing the wearer to see clearly at all distances. These lenses also have the benefit of looking better - they don't draw attention to the ageing process. 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. Your optometrists or dispensing optician will be able to advise you on the best lenses to suit your individual requirements.
Edmonds And Slatter Opticians have been awarded Essilor's Varilux Gold Specialist accreditation, achieved as a result of our understanding and appreciation of progressive lens technology. We are committed to fitting the finest products available for the benefit of our customers' visual comfort. Not all progressive addition lenses (PAL / Varifocals) are alike. It is essential that the correct product is chosen for the purpose for which it is intended, and then carefully fitted to ensure the dynamics of the lenses are fully utilized.
Thin & Light 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.
Whatever your prescription, it is important to protect the eyes against excessive ultraviolet (UV) radiation. Protection is needed to avoid reflected light from sand and snow or if you spend long periods out of doors, particularly in the summer. Prescription sunglasses can be made with single-vision, bifocal or varifocal designs to offer the same standard of protection as non-prescription sunglasses.
Photochromic or Transitions Lenses
Photochromic lenses react to light so that indoors or in dull conditions they have a light tint, and in bright light they darken to eliminate glare and protect the eyes against UV. Modern photochromic materials react and fade quickly, suit most prescriptions and are more likely to be lightweight plastic than glass.
Polarising lenses eliminate 99.9% of glare from horizontal surfaces such as roads, water and snow and therefore are ideal for fishing, sailing and driving.
Spectacle lenses can be provided with anti-reflection coatings which virtually eliminate distracting reflections off the lens surfaces. Reducing reflected light is particularly helpful for computer users and for night driving. Anti-reflection coatings also improve the cosmetic appearance of your glasses and can make thick lenses look thinner.
Scratch Resistant Coating
Plastic lenses are lighter than traditional glass lenses but they scratch more easily. Scratched lenses can be irritating for the wearer and look unsightly. Scratch-resistant coatings are available to protect against damage and prolong lens life.