subject: Contact Lenses: History And Function [print this page] Contact lenses have been with us for decades now, but many people only think of them as a modern corrective invention. However, even people who wear contacts with some regularity may not know precisely how or why they work, just that when they wear them they can see better. However, there's more that goes into even the simple lenses than the supposed magic that corrects farsightedness, nearsightedness, astigmatism and even presbiopia.
When you put your contact lenses in what you're doing is slipping a lens over your cornea and beneath your eyelids. This lens serves the same function as a pair of glasses would, but rather than putting the lens in a frame and wearing it in front of your eye it's held in place by the pressure of the eyelid and the pull caused by pressing it firmly over the layer of tears that is always coating the visible part of the eye anyway. The lens, which is made specifically to correct the vision problems of the wearer, alters the way the eye perceives light and thus it changes how the person wearing them sees, refocusing their vision so that normal sight is once again possible.
The birth of the contact lens as an idea actually goes all the way back to the 1500s, as sketches by the celebrated inventor Leonardo Davinci have shown us. Of course lenses at that time would have been glass, which would have been exceedingly dangerous. The idea lay dormant for some time, but in 1827 new life was breathed into it by Sir John Herschel. Herschel's idea was that if you could make a mold of the patient's eye, then you could form a lens that fit it exactly. It wasn't until 1887 that the first recorded glass contact lenses were made by a German glassblower, however. It wasn't long after this that a Swiss doctor by the name of A. E. Frick along with the aid of a French optician Edouard Kalt fit the first glass lenses onto a patient's eye. The lenses were heavy, and took up significantly more of the eye than modern lenses, and they could only be worn for a few hours before they had to be removed.
Modern, plastic lenses didn't get their start until the year 1936. The first hard plastic lens was actually made with a central glass lens surrounded by plastic. Then later in the year 1948 a California optician invented lenses that were made entirely of hard plastic, which you could say was the first, modern contact lens in the sense that patients no longer had to put glass into their eyes in order to see properly without the aid of glasses. Technology advanced at a rapid pace, but even so it wasn't until the 1960s that the first soft plastic contact lenses were invented by Dr. Ottoe Wichterle, who had used parts of his son's erector set in the design for the final mechanism. He was also the man that had invented the soft plastic compound in the first place, making him almost totally responsible for this discovery.
From that point on it is, as they say, history. The function of contact lenses hasn't changed much in the hundreds of years since the idea was first put forth by scientists and inventors, but the materials the lenses are made from, the size they have to be and how long a person can wear them have all changed along with the limits of times and technology. Today they're just a common item for many people, but centuries of thought have gone into them.
