Discover The Interesting History Of Contact Lenses
About 125 million people in the world are estimated to currently wear contact lenses
. Although this now ubiquitous vision correcting device seems to be a fairly modern invention, the humble contact lens actually has a surprisingly long and storied history.
Birth of an Idea
The first clever scientist to dream of the concept of a corrective lens that rest right against the eye is widely accepted to be Leonardo da Vinci. However, da Vinci couldnt have even considered the use of modern plastics, which compose contacts today. His first work on the subject, in 1508, suggested the use of a bowl of water as a refractive lens that the eye would be submerged in.
A Long Wait
The next great thinker to advance the matter didnt come along until another century had passed. In 1636, the French philosopher and physicist Rene Descartes proposed a glass tube filled with liquid that would rest directly against the eyeball. Of course, this rather precarious method was deemed impractical, as it eliminated the ability to blink.
An Even Longer Wait
The following major work on the long road to contact lenses had to wait two more centuries. In 1845, multitalented British scientist Sir John Herschel proposed two crucial ideas that led to the modern contact lens. They were the use of a spherical capsule filled with gelatin and a precise mold of the cornea that could be impressed on a transparent medium (such as glass) to correct vision impairment. Unfortunately, Herschel never put these ideas to an actual test.
The First Contact Lenses
The development of modern contact lenses experienced their most significant movement toward common feasibility in Germany during the year of 1887. The first lens that could be tolerably worn on the eye was created by a glassblower by the name of F.E. Muller. The same year, the ophthalmologist Adolf Gaston Eugen Fick, working with rabbits at first, created a lens from blown glass that rested on the sclera, also known as the white part of the eye.
These primitive contacts were about as wide as a penny and relied on a well of tears or Dr. Ficks own dextrose solution filling the gap between the glass and the cornea. They could only be worn for brief periods of time, rendering them impractical and far from a useful replacement for glasses, which had been use widely for centuries by this time.
The First Plastic Lens
Contact lenses remained an unwieldy oddity, useful for only extreme situations and experiments until a better material for their construction was invented in the 1930s. In the year 1936, American optometrist William Feinbloom created a new type of contact lens, made of a form of plexiglass called polymethyl methacrylate. These lenses were much lighter and more comfortable than their hand blown predecessors.
In 1949, the size of this new breed of contact lens was reduced to fit snugly over the cornea, rendering them much more comfortable to wear. This new generation of hard contacts could also be worn for up to 16 hours at a time. Finally, a viable alternative to the thick plastic frames that were then in vogue was available to the general public.
Although contact lenses were gaining popularity through the 1960s, they had a number of drawbacks as well. These early contacts firstly lacked the ability to let oxygen get through to the cornea, essentially suffocating the eye. Furthermore, the contacts of the day were extremely fragile and very expensive.
The Modern Contact Lens Emerges
In 1971, the Food and Drug and Drug Administration approved the use of the material that soft contact lenses were made of in the United States. The material, called Soflens, was developed by two Czech chemists beginning in 1959. Since then, further chemical work on Soflens has led to soft contact lenses that allowed increasing amounts of oxygen to permeate through to the cornea.
Soon after the introduction of soft contacts, the more antiquated, expensive and uncomfortable hard lenses saw a rapid decline in use while soft contacts exploded onto the American market. Improved versions of soft contacts, specifically models that increase oxygen permeability, are still being introduced onto the market today. The latest models allow users to wear their lenses even as they sleep.
Today, not all contacts are used for vision correction. The advent of cosmetic contact lenses has fairly recent become available to the general public. Cosmetic lenses can be used to change the color of the eye or provide theatrical effects for films and plays or general use. Cosmetic lenses can sometimes cause irritation of the eye or even obstruct vision, causing blurring and blocking light.
Despite the advances in contact lens technology through the years, glasses still remain more widespread and popular than contacts. But for many people, contacts provide a great deal of freedom and convenience.
by: Russell Tyler
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