LENSES
LENSES
Spectacle lenses come in a large number of different materials, designs, tints and coatings. The sheer number of choices can be bewildering. We, at Richard Suckling Optometrists, have had years of experience to help you make the lens decision which is best for you.
Today lenses can be made much thinner and lighter than ever before. High index materials can dramatically reduce edge thickness for myopes (shortsighted people) and for people with higher prescriptions. Flatter aspheric lens designs can reduce the bulbous appearance of some hyperopic (longsighted) people’s prescriptions.
Lens coatings and tints have improved too, in recent years. Slippery multicoated lenses, which are much easier to clean, are now available. Multicoated coated lenses reduce annoying reflections, look nearly invisible and have a nicer, more fashionable appearance. Photochromic lenses, which darken and lighten in the sun, now change much faster than they ever used to.
HIGH INDEX LENSES
High index lenses are not only thinner than standard lenses but are often lighter and stronger. If you have a higher-powered spectacle prescription, high index lenses along with a multicoat should be your first choice.
High index lenses are made from materials that bend light more than standard materials. The higher the refractive index of a lens, the greater its ability to bend light. High index lenses come in a variety of refractive indexes, some varieties bending the light much more than others. High index lenses can be made much thinner than other lenses. The higher the refractive index, the thinner the lenses can be for a particular lens power.
However, it pays to remember that although high index lenses have many benefits not all high index lenses are created equal. For instance, polycarbonate, a medium index plastic material sometimes causes colour fringing which degrades the image.
Because there are many varieties of high index lenses it pays to get advice about which varieties will be best suited to your particular prescription requirements. Our job is to help you make the right choice. We even have a computer programme to help us. It calculates just how thick any variety of high index lens will be in the frame that you have selected.
COATING & MULTICOATS
Today’s spectacle lenses are usually made from plastic that is then coated with a scratch-resistant coating to make it durable and long-lasting. There are also special extra hard-coated plastic lenses suitable for children. Some of these scratch-resistant coatings also incorporate a UV filter that filters out nearly all of the sunlight’s harmful rays.
Spectacles made from glass, although still available, are really a thing of the past because of their poor safety record and their weight. Glass lenses are not usually coated.
Multicoats are special coatings layered one on top of the other to eliminate reflections and increase the amount of light transmission through the lens. Multicoated lenses effectively eliminate reflections making driving at night and viewing computer screens more comfortable. They also have a much nicer and more fashionable appearance.
Multicoated lenses greatly reduce the edge power rings effect of lenses with thicker edges. Also, multicoats help to reduce the colour fringing (chromatic aberration) seen with some high index lenses. Multicoated lenses are recommended for stronger prescriptions and for flatter aspheric designed lenses.
The three main multicoats we use are Prevencia, See Coat Blue, Crizal Forte and Crizal Sapphire .
BIFOCALS & PROGRESSIVES
Progressives (sometimes called multifocals) and bifocals are lenses designed for people over 40 who have presbyopia. The number one reason people get these lenses is convenience, so that they don’t have to take their spectacles on and off all day.
Bifocals are lenses with two focal lengths, one designed for distance and the other designed for near. They give good distance vision in the top half of the lens and good reading vision in the lower half. However, there is a bit of a no-mans land between these two visions often making working on a computer, playing music or playing a sport like golf, difficult. Seeing prices on the supermarket shelf may be difficult and even walking on uneven ground can be because you can’t see the bumps and hollows in the ground.
Progressives (multifocals) are now much more popular than bifocals and with the newer better designs this trend will continue. Progressives do not have a line between the top half and the bottom half of the lens. They progress smoothly in power increments through a middle part of the lens that can be used for intermediate vision tasks like looking at the computer or at prices on the supermarket shelf. However, progressive lenses have weaknesses. Generally speaking, the reading portion of progressive lenses is narrower than that of bifocal lenses and they can take a bit of getting used to wearing, often 2 or 3 weeks. Some people find that progressive lenses give them problems with motion sickness.
Progressive lenses also come in a large number of different designs. Some designs are more suited for reading while others are more suited for walking. Still other designs are for shallow spectacle frames and others, like occupational progressives, are for those working on computers. It is important to make an informed choice about which lens is best for you.
All our progressive and bifocal lenses are of the highest quality material and designs. They are made by companies like Nikon, Essilor and Zeiss.
PHOTOCHROMIC LENSES
Photochromic lenses are variable tinting lenses that darken when the sunlight shines on them and lighten to become clear when they are out of direct sunlight. Photochromic lenses can be made in plastic or in glass. Sometimes people refer to photochromic lenses as transition lenses because one brand of plastic photochromic lenses is called ‘Transitions’.
Photochromic lenses are a wonderful choice for those people who are sensitive to sunlight, for those people who are migraine prone and for those people who spend a good part of their day outside. Outside, progressive lenses act like sunglasses while inside they are basically clear. Although progressive lenses darken in the car, they do not darken as much as one would expect because they are out of direct sunlight, shielded by the windscreen.
PRESCRIPTION SUNGLASSES & TINTED LENSES
Tired of your sunglass fit over or clip-ons? Separate prescription sunglasses might be a good option for you. The most straightforward prescription sunglasses have lenses with a permanent tint . This tint has a special dye that reduces that the visible light down by 70-80% and cuts out all harmful UV light.
The most popular sunglasses lens tints are grey, green and brown. Sunglasses with grey lenses and with grey plus a touch of green give the most natural colour while brown lenses give the most cheerful appearance. However, we can provide a wide variety of colours and are able to match almost any colour you might require.
Polarised lenses are a great choice for driving and for fisherman. These cut out reflected light so it is possible to see into water because the lenses cut out all the reflected light off the surface. Similarly, glare reflected off the road while driving is also eliminated. It is now possible to get a polarising, photochromic, sunglass lens, which varies the amount of tinting depending how bright the sun is.
We will use a nice fashion sunglass frame modifying the spectacles prescription to allow for the wrap of the sunglass frame.
Special Tints
Did you know that special tints are available for shooting and skiing?
Did you know that you can have your ordinary spectacle lenses tinted and turned into sunglasses?
Come in and talk to us about any special requirement lens tints you might want.