What are Contact Lenses?

Eyeglasses, also known as spectacles, have been used for over a century to correct visual impairments. While an effective and cost efficient tool, some people find their weight and presence a burden, while others just don’t like the look of them. Fortunately in recent years the invention of contact lenses has provided an alternative. The traditional image of an optician is of someone dispensing eyeglasses or spectacles. However the prescription and supply of contact lenses is also a key part of their role, particularly as the popularity of contact lenses increases.

What is a contact lens?

Like all corrective lens, the purpose of contacts is to compensate for a defect in the eye that causes blurry vision. A contact lens is worn directly over the eye, and is often chosen for convenience and the sense of liberation being free of glasses can give you. Almost anyone wearing glasses can opt for contacts, whether as a permanent replacement for their specs or as a part time measure for nights out.

Contact lenses float on the film of tears which naturally covers your eye. This surface covering is designed to lubricate the surface of the eye and hence prevent it from drying out, and because contacts are placed on top of this layer, you barely feel their presence when they’ve been put on.

Like traditional corrective lenses, contacts work by causing light from the objects around us to be focused on the retina as it should be to create an image our brain can understand. Visual difficulties are often caused by a change that disrupts the focusing of light on to the retina, for example in the farsighted light is effectively focused behind the retina because of a small eye ball or abnormal cornea. The result is a blurring of images that are nearby that can be compensated for by means of a corrective lens.

Like traditional lenses, contacts are shaped to correctly focus light. For farsighted people as mentioned above, the lens is convex (curving outwards) and is hence thickest at the centre, which adjusts the focus as necessary and produces a clear image. Conversely shortsighted people, often possessed of a longer than usual eyeball, have a concave (curving inwards) lens that is thinnest at the centre. This focuses the image properly on the retina (the back of the eye where an image is formed) as it should be.

Astigmatism is a common condition which can also be corrected by contact lenses. In this condition the shape of the eye’s lens or cornea (a clear part of the front of the eye also responsible for focusing light) is not spherical as it should be and more closely resembles a rugby ball.

These are the most commonly occurring visual conditions for which people often use contacts as their corrective lenses.

How do I get contact lenses and what does an optician have to do with it?

If contact lenses sound like the option for you, then chances are your optician will bring it up during your next eye test. Opticians (also known as optometrists in the UK) are individuals who are qualified and registered to assess the condition of your eyes and prescribe the necessary corrective lenses. They are not to be confused with dispensing opticians whose only role is the provision and preparation of corrective lenses.

After an eye test to ascertain the state of your vision, your optician will discuss your options with you. Bar cases of extreme myopia for example, and other conditions that require more than corrective lenses like cataracts or retinopathy, if you need glasses, you are eligible for contacts.

Simply opting for contact lenses is not the end of it however, as there are other choices to be made and steps to be taken. You will be asked to choose between disposable or extended wear lenses, the former, as the name suggests, are single use lenses that you discard after use. On the other hand extended wear lenses are kept for a certain period of time, typically one month (hence the moniker ‘monthlies’). Each have their pros and cons and will be suitable for different lifestyles, which is where your optician comes in. He or she will have experience in these matters, and therefore is able to advise you as to which would suit you best.

Education is an important part of the optician’s role when it comes to contacts. As you can imagine, poking at your eye with a soft lens at the end can be dangerous if not done carefully and properly. Your optician will explain to you the dos and don’ts, including for example sleeping with your contacts in (a don’t!) and washing your hands thoroughly before and after applying and/or removing your lenses (definite do!).

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