At Straine Opticians we use a variety of different lens manufacturers to ensure that we are always able to supply our patients with a product that accurately matches their individual needs.
There are many lens manufacturers, each trying to make lenses thinner, lighter and more resistant to wear and tear. Certain types and finishes of lenses are particularly suitable for different working conditions or leisure activities. Advanced plastic materials mean that lenses are better able to cope with the rigours of everyday wear and are lighter too. This allows much more freedom of choice even if you have a higher prescription. If you enjoy participating in sports then polycarbonate lenses could be a good choice for you as they are highly impact resistant, thin and light. An anti-reflective coating is especially useful for reducing glare – from car headlights when driving at night or from your computer screen if you are a regular VDU user. Whether your need is for lightweight, impact-resistant, UV blocking, tinted, anti-reflective, polarised or a combination of all these benefits, we can advise you on the best lens for your needs.
- Single-vision lenses
- Varifocal or progressive lenses
- High-index and aspheric lenses
- Anti-reflection coating
- Scratch-resistant / hard coating
- Polarised lenses
- Photochromatic Lenses
- Zeiss Vision Centre
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 ( no lines!)- they don't draw attention to the ageing process. A range of varifocal designs is available depending on your lifestyle and occupation e.g. an architect or graphic designer would need a wide area for their intermediate vision. Modern lens technology means that there are many different designs and materials to choose from. Your optometrist or dispensing optician will be able to advise you on the best lenses to suit your individual requirements.
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. We at Straine Opticians have a Zeiss Relaxed Vision Centre, which enables us to calculate your exact lens requirements. The Zeiss Relaxed Vision system offers crystal clear, comfortable vision thanks to optimised measurement and premium lens quality.
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.
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.
A polarising film is placed between two layers of the spectacle lens during the manufacturing process. This film makes light rays vibrate in a different a pattern as to reduce the reflection from any shiny surface such as water, snow and other reflective surfaces. This film make light rays vibrate in a different a pattern as to reduce the reflection from any shiny surface such as water, snow and other reflective surfaces. This is illustrated in the images below.
Photochromic lenses react to light so that indoors or in dull conditions they have a light tint, (essentially invisible) 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. They are a useful way to protect your eyes from age related conditions like cataracts and macular degeneration, which are directly affected by UV exposure.