How has the Invention of Contact Lenses affected people’s Sight Essay
People with sight troubles have had the possibility of wearing glasses for a really long time, but the new technology made available contact lenses. In this essay, I am going to look at the different contact lenses types that exist, at who invented them and when, for which vision problems they are solution, at how to take care of them, at how common they are in our society and finally, I will write about my own opinion.What contact lenses areAccording to the Macmillan Dictionary (2002), contact lens may be defined as “a plastic lens that you wear in your eye to help you see more clearly”.A very wide variety of contact lenses are available in today’s society, including hard and soft (even if soft is by far more common now), disposable and extended wear; this makes it easy for each person to chose the appropriate type of contact lens for her. The main types of contact lenses are listed below:* Soft lenses: As these lenses are soft, they are made of a large percentage of water, and this allows oxygen to pass through the lens and reach the cornea. They are also more comfortable and easier to adapt to.* Rigid-gas permeable lenses: these lenses are not made of water so they are not as comfortable as the soft ones, but they do allow a larger amount of oxygen to pass through them. Their best advantage is that they offer a excellent sight correction.* Disposable lenses: Disposable means that the lenses are worn for a definite period (from two weeks to six months depending on the lenses) of time before being thrown away and replaces by a fresh new pair. The fact of throwing out the lenses helps making sure the lenses are always very clean, so healthier and more comfortable.* Extended wear lenses: these lenses are made to be worn 24h a day, and up to seven days on a row (a new type made of ‘silicone hydrogel’ allows more oxygen to flow in so that they can be kept for up to 30 days without taking them off).* Bifocal contact lenses: this type of lens has two major functions: to correct distance vision and to correct near vision. There are two main designs: the power or seeing far is concentrated at the top and the one of seeing nearby at the bottom, or the different powers are blended on different parts of the lens.* Coloured contact lenses: they can be used to correct existent sight troubles, but also just to look prettier, as they come in a large variety of colours, from hazel to blue, passing by grey, purple and green.However the lenses type that is mostly used today is a combination of both soft and disposable lenses, simply called the disposable soft contact lenses, because they are the healthiest ones, more comfortable, and major prices differences from an average model of these different types of lenses do not exist.When and by who they were inventedThe famous Italian inventor Leonardo da Vinci was the first one to come up with contact lenses sketches and explanations, at the beginning of the 16th century. It is only in 1801 that Thomas Young developed the idea Rene Descartes had had more than 150 years before. Thomas Young, who was a British physician, took small lenses from his microscope, covered the edges of them in soft wax and put them into his own eyes to correct his vision.In 1887, the glassblower F.E. Muller produces the first lens designed to be seen through and tolerated; (however, according to the book 100 greatest medical discoveries, it is the American Louis J. Girard who developed the first contact lens this same year). Almost half a century later, the American William Feinbloom is the first one who creates an US-made contact lens and introduces the use of plastic in it.After few improvements such as making the inner-surface of the corneal lens follow the eye’s shape (instead of sitting flat) or also the use of a new material, a softy water absorbing plastic, it is in 1971 that the soft lens became available for commercial distribution in the United States. New models of lenses, each time with more improvement, were then created and commercialised (around a new model every two years).In 1987, a great evolution can be established: disposable soft contact lenses and the first multipurpose lens care product (explained in more details further) were available for commercial distribution, as well as a soft contact lens able o change the eye colour: this is the start of contact lens’ use in fashion.For who (explanation of vision troubles)Contact lenses were designed for people who cannot see properly, and nowadays they are definitely developed enough to be able to correct almost all the vision troubles. The 5 main vision conditions are the following:* Astigmatism: this condition usually affects both nearsightedness and farsightedness because the cornea’s curvature is rather oval when it should be round. Their sight is not prï¿½cised and for example, they can confuse the letters M, N and H, or B and D. It is often associated to myopia or hyperopia.* Hyperopia: this is a long-sightedness condition, and people affected by it have difficulties to focus on close objects, while the sight of distant objects stays correct. It might be because the cornea is too bulging, or because the crystalline lens (see eye diagram) of the eye is too flat.* Myopia: also known as short-sightedness, people affected by this condition are able to do tasks that require a vision of nearby objects, such as reading or sewing; but they see distance objects blurred so for example, they cannot read highway signs.* Presbyopia: this long-sightedness condition cannot be avoided because it touches everyone at some point in life (usually around 40-50 years old). It is due to a loss in flexibility of the lens and loss of power of the ciliary muscles and it cause the person to have difficulties in focusing on nearby objects. A person affected by this condition will for example hold her newspapers further away from her eyes to see it better (we say that the “arm grows shorter” because it is not able to hold the object at a distance long enough for these people to see anymore).* Strabismus: this condition, also called lazy eye, makes us squint; there is a lack of coordination between the muscles of the two eyes, and this means that the vision axes of our two eyes are not parallel so they don’t point out at the same direction. This affects our depth perception.The following eye diagram will help understand which parts of the eyes are damaged by the previously explained conditions:How to use themYou definitely need to consult a specialist who will tell you the type of contact lenses that are the most appropriate to your case: the optometrist will prescribe the lenses to you and the oculist will provide them. Your ophthalmologist will explain you how to put them on; it might look hard at the beginning but it’s just a matter of getting used to it. But two rules are still primordial: to make sure you have clean hands before you put your lenses in your eyes and not to wear them for than the indicated time.It is very important to take care of you contact lenses; indeed they need regular cleaning and disinfecting to retain clear vision and prevent infections. Eyes were not designed to have a foreign object in them. Plus this ‘foreign object’ prevents the air to reach the eye, while this sight organ needs to receive oxygen. Contact lenses make your eyes vulnerable to all sorts of things so by cleaning them, they are less likely to breed bacteria and they are more air permeable. A large variety of products is nowadays available to clean, rinse and disinfect your lenses:* Saline solution: once the lens was cleaned, this solution is used to rinse it.* Daily cleaner: this cleaner is used once a day, to clean the lenses. With a few droplets of the cleaner on it, the lens is rubbed for about 20 seconds on each side. Long nails mean to be extra careful with the rubbing!* Multipurpose solution: this solution is used for rinsing, disinfecting, cleaning and storing the lenses. It can be used only for disinfection and storage if it is associated with another rinsing product (eg: Saline solution) and a cleaning one (eg: daily cleaner).Some products may contain preservatives such as thimerosal. To avoid any kind of problems due to these preservatives (even if many brands no longer use products that contain preservatives), it is safer to chose products with the label ‘for sensitive eyes’, and these products usually have an expiration date.How common they are in today’s societyContact lenses are greatly used in today’s society. Even if they are basically made to cure vision troubles, they are more and more used for appearance aspects: many people would rather wear contact lenses than glasses because they look prettier, and because you have fewer troubles with them. few examples include the “nerd stereotype” changing from glasses and becomes beautiful, or the athlete who can play sports without fear of shattered glasses, or also the actor able to switch his eye colour from brown to red, passing by blue, depending on the role. Teens are the main people wanting to switch their glasses for contact lenses, for cosmetic reasons: they will feel more self-confident and good looking without their glasses. But before contact lenses are prescribed to this category of people, it is important to make sure that they are responsible enough to take care of their contacts. Teens are also the best costumers to buy colour contact lenses in order to change their appearance: more than just changing the colour of your eye, special contact lenses are now available for special occasions, such as Halloween with contacts that give you cat’s or vampire’s eyes.So it is very common nowadays to see people wearing eye contacts even though they don’t need them for their sight. However, a prescription is always needed because wearing contact lenses is still considered as a medical application. And the fact that they are more and more common in today’s society should not make us forget their first aim was for helping see and so they need special care, even if they are only being used as a fashion accessory. More than that, secondary effects might happen, such as fatigue and headaches, and those are stronger if it takes time for the eyes to adapt to the contacts.Also be careful when putting make up on: always put your contacts before the make up and take them off before you use makeup remover. Also it is preferable to use non-allergenic makeup.Own opinionI personally don’t wear contact lenses because I don’t have any vision troubles and I don’t resent the need to change the colour of my eye or anything, but I really think that they are very useful and helpful. I do know some people who hated wearing glasses, and after they tried contact lenses, they felt prettier and better. I also think that contacts are helpful for people who play sports; even in the school’s basketball team, few girls wear contacts and it is very useful because this way they don’t get hurt; also there is a French commercial for contact lenses that is performed by three famous French athletes, proving that athletes do use contacts. I also think it is nice that actors are able to change their eye colour in order to add little details that make the character more reliable.Nevertheless, contacts are still “foreign objects” put into your eyes, they might cause secondary effects (such as headaches, seen before) and they need special cleaning equipment. So I think that we have to be careful because if they become too common only as a fashion accessory, then people are going to forget a little bit the medical side of contacts and so they might damage someone’s eyes if they are not being used properly.ConclusionIn conclusion, the invention of contact lenses has greatly affected people’s sight: eyeglasses are not the first solution to solve vision troubles anymore, because contact lenses have replaced them. They have been so successful because they are easier to use, more discrete and practical as well. And it is more and more common to see people wearing coloured ones them only for the fashion side.However it is important to remind that their first purpose was for medicine, and they require special care that people have to follow, even if they just contacts as fashion accessories.