The evolution of the contact lens from cumber-some eyewear to sports performance aid has been a remarkable one. The original, and fragile, contact lens was not an ideal fit in the unpredictable world of sports, although for many athletes it represented a great step forward from the only other option—bulky and peripheral vision-limiting athletic eyeglasses.
Contact lens technology has evolved from the hard, glass lens to a very soft, thin plastic composite product. The development of a sport-specific contact lens has occurred in recent years, driven by the desire of professional athletes to use not simply a lens that properly corrects their vision, but one that increases their ability to see more clearly. One of the first successes reported in the use of a sport-specific contact lens was that experienced by American drag racer Gary Scelzi, who had been diagnosed with an astigmatism, caused by an irregularly shaped cornea that tends to distort vision in the subject eye. Sclezi was prescribed lenses that corrected his vision to beyond the accepted standard or optimum, known as 20/20 (where the wearer can see at a 20 ft [6 m] distance what a normal person may see at 20 ft), to 20/15. The lens was also specifically created to give Scelzi an enhanced fine-depth perception. Sclezi noted a dramatic improvement in his ability to react to the starting lights that govern drag racing.
The modern sport contact lenses can also be modified to filter out certain light wavelengths to accentuate a particular visual element in a sport, often in those disciplines that involve that athlete reacting to the position of a ball in relation to a background. The lens tint is used for athletes with myopia (nearsightedness) or hyperopia (farsightedness). In outdoor sports, such as football, golf, or running, the sport lens is tinted gray-green, which permits the wearer to better distinguish between the shades of a certain color, such as the green a golfer will see on a fairway, as opposed to that of the putting surface.
A number of professional baseball players wear an amber-tinted contact lens for games played in variable lighting conditions. The amber tint blocks blue light from being received into the eye, and it is believed that this enables the player to better see fast-moving objects, such as a baseball, against a fixed background.
The enhanced contact lens technology may provide a certain psychological lift to the athlete in addition to the physical correction of vision. In many sports where hand-eye coordination is the premium skill, if the athletes believe that they can see the target object better, they may in fact perform better because they will mentally simulate the activity more effectively prior to making the actual play.