"Viewing a computer or digital screen often makes the eyes work harder. As a result, the unique characteristics and high visual demands of computer and digital screen viewing make many individuals susceptible to the development of vision-related symptoms. Uncorrected vision problems can increase the severity of computer vision syndrome (CVS) or digital eyestrain symptoms. Viewing a computer or digital screen is different than reading a printed page. Often the letters on the computer or handheld device are not as precise or sharply defined, the level of contrast of the letters to the background is reduced, and the presence of glare and reflections on the screen may make viewing difficult."
Computer vision syndrome (CVS) is a condition resulting from focusing the eyes on a computer, smartphone or other display device for protracted, uninterrupted periods of time and the eye's muscles being unable to recover from the constant tension required to maintain focus on a close object.
"There isnt a name for it and few eye doctors test for it. But many people are having trouble seeing in the middle distance that demands so much of our focus. Some 80% of us use computers, staring intently on screens set well between typical distance and reading range, often for many hours each day. Add in laptops, pagers, e-readers, smartphones, personal-digital assistants and hand-held video games, each with its own optimum..."
"One reason the problem is so pervasive: Unlike words printed on a page that have sharply defined edges, electronic characters, which are made up of pixels, have blurred edges, making it more difficult for eyes to maintain focus. Unconsciously, the eyes repeatedly attempt to rest by shifting their focus to an area behind the screen, and this constant switch between screen and relaxation point creates eyestrain and fatigue. Another unconscious effect is a greatly reduced frequency of blinking, which can result in dry, irritated eyes. Instead of a normal blink rate of 17 or more blinks a minute, while working on a computer the blink rate is often reduced to only about 12 to 15 blinks. But there are additional problems. The head’s distance from the screen and position in relation to it are also important risk factors. To give the eyes a comfortable focusing distance, the screen should be about 20 to 26 inches away from the face. The closer the eyes are to the monitor, the harder they have to work to accommodate to it."
"With the increased use of electronic devices with visual displays, computer vision syndrome is becoming a major public health issue. Improving the visual status of workers using computers results in greater productivity in the workplace and improved visual comfort."
"CVS, or digital eyestrain, can be diagnosed through a comprehensive eye examination. Testing, with special emphasis on visual requirements at the computer or digital device working distance, may include:"
"Worldwide, up to 70 million workers are at risk for computer vision syndrome, and those numbers are only likely to grow. In a report about the condition written by eye care specialists in Nigeria and Botswana and published in Medical Practice and Reviews, the authors detail an expanding list of professionals at risk — accountants, architects, bankers, engineers, flight controllers, graphic artists, journalists, academicians, secretaries and students — all of whom “cannot work without the help of computer.” And that’s not counting the millions of children and adolescents who spend many hours a day playing computer games."
"Solutions to digital screen-related vision problems are varied. However, they can usually be alleviated by obtaining regular eye care and making changes in how the screen is viewed."