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PART 1 Introduction About 25 million Americans are 65 and older. That figure will double during the next 25 years. Over the next ~ 5 years, the baby boom generation will swell the ranks of middle-aged workers. But the numbers tell only half the story. The gradual decline in visual functioning that usually accompanies aging often goes undetected or is deemed untreatable. Older people may have difficulty seeing at night, reading small print, distinguishing similar colors, or coping with glare from a desktop or video display terminal. Yet most older Americans do not have severe impairment, and only about 10 percent have eyesight so poor that they can barely see the largest printed line on an eye chart. Age-related visual impairment is highly variable. It may become significant as early as age 40, or it may not pose a problem until well into the 60s or 70s. Unless they have a major eye problem, however, most workers do not see eye specialists or undergo regular eye checkups. Many people think of impaired vision as an inevitable part of aging for which little can be done. Some fear that if they ask for help, their job will be in jeopardy. More than likely, most older people are simply unaware that their eyesight has deteriorated. Yet there are simple, often inexpensive methods to enhance the eyesight of older workers. Providing stronger lighting, increasing color contrast on stairwells, repositioning a desk or video display terminal to reduce glare these are changes that most companies can afford to make. Providing regular eye checkups for workers over 40 can catch problems early, when they can be most effectively treated. In addition, giving older workers specific job training and encouraging them to practice visual tasks may help them compensate for their declining sight and profit from their learning skills and years of expertise. A corollary is that money invested in retaining older workers with impaired eyesight may be well spent: older employees take about the same amount of sick leave and are as productive as their younger counterparts, according to recent studies. In short, many businesses, like many workers, are unaware of methods to improve vision or accommodate impaired vision. Better vision improves the quality of life for workers and can boost productivity. What the middle-aged Ben Franklin said about his invention of 10

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"I am a camera, with its shutter open .... Christopher Tsherwood When a beam of light reaches the eye, it first encounters the cornea, a tough, dime-sized membrane that is kept moist and nourished by tears. The cornea's rounded, bulging shape, like a convex camera lens, bends light rays together to form an image at the back of the eyeball. It is the cornea that provides virtually all the focusing power needed to see objects more than 20 feet from the eye. Behind the cornea is the iris, a doughnut-shaped piece of tissue that is the gateway for light in its journey to the back of the eye. Opening and closing like a camera's diaphragm, the muscles of the iris regulate the amount of light entering the pupil, the opening in the center of the iris. In a dark room, the pupil grows to 16 times its size in bright light. Insight passing through the pupil strikes the lens, a trans- parent structure about the size of a lima bean. For distant objects, the lens thins and flattens, decreasing its ability to bend light rays. For nearby objects, which cannot be focused by the cornea the lens fattens and bulges, increasing focusing. "double spectacles" (bifocals) holds true today in redesigning the workplace for older people: EWithout glasses] ~ cannot distinguish a letter, even of large print, but am happy in the invention of double spectacles, which serving for distant objects as well as near ones, make my eyes as useful to me as ever they were. If all the other defects and infirmities were as easily and cheaply remedied, it would be worth while for friends to live a great deal longer.

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