Featured Research

from universities, journals, and other organizations

New Way Of Prescribing Glasses Reduces Computer Eye Strain

Date:
January 5, 1998
Source:
Lewis And Clark College
Summary:
Red, sore eyes. Fatigue. Headaches. Blurred vision. If you work long hours on a computer, you know the symptoms.

PORTLAND, Ore.--Red, sore eyes. Fatigue. Headaches. Blurred vision. If you work long hours on a computer, you know the symptoms.

As far back as 1991, a Harris poll identified eyestrain as the top office-related complaint, affecting 47 percent of all office workers.

"It's scary to think of the long-term effects computers will have on my eyes," says Lewis & Clark College senior Leland Peterson.

Peterson has been known to sit in front of his computer for 16 hours straight. Between his studies and his computer-related campus jobs, he spends at least five hours a day, seven days a week looking at a computer monitor.

"I get a little dazed after a while," he admits. "Images start to melt together."

Emily French '88 uses a personal computer at work and a laptop for notetaking in her law school classes at night. At home, she has two laptop computers and a large PC--all networked.

"We're very 90s," she quips.

She figures she spends a minimum of six hours a day staring at a computer screen. She suffers from blurred vision, sore eyes and even headaches.

Eye-care clinicians are seeing more and more patients like Peterson and French with computer-related problems.

"The numbers are expanding across the spectrum," reports Dr. Cosmo Salibello, a Portland optometrist. "We now see children, 6, 7 or 8 years old who are suffering from visual stress. And we certainly see computer-related symptoms with college students, who spend many hours on the computer doing research and writing papers."

All this is troubling news to students and workers whose futures depend on computers. But a new technology for prescribing glasses offers hope for markedly reducing eyestrain.

Erik Nilsen, assistant professor of psychology at Lewis & Clark, and Lewis & Clark student researchers have conducted three major studies to evaluate the new technology.

Nilsen, a respected researcher on human-computer interaction, explains that an image on a computer screen differs remarkably from a printed image on paper.

A black character printed on white paper has well-defined borders, sharp contrast and constant density. On the other hand, characters on a computer monitor are formed from a series of dots called pixels. A pixel is brighter in the center and dimmer and fuzzier around the edges.

"Our eyes have a very hard time remaining focused on these images," Nilsen explains.

The result is that we must constantly refocus when working at a computer. Salibello describes this constant flexing of the eye muscles as a form of repetitive stress--like carpal-tunnel syndrome.

"Our focusing system is pushed and pulled 15,000 to 20,000 times during each work day," he says.

Most optometrists use the Snellen chart, characters printed on paper, to prescribe glasses. But Salibello and his colleagues have developed a diagnostic tool called the PRIO VDT vision tester to simulate the image on a computer monitor and to duplicate the visual experience of a typical computer user.

Nilsen and Salibello analyzed data collected from 324 patients who spent at least two hours per day working in front of their computer monitor to describe the typical visual stress patient. Then Nilsen conducted a double-blind experiment to compare the effectiveness of glasses prescribed using the PRIO system with glasses prescribed using the Snellen method in reducing visual stress for computer users.

The Lewis & Clark researchers recruited 37 subjects. Each used computers at least two hours daily, wore corrective glasses or contacts, and reported visual stress symptoms. Each subject received two sets of eyeglasses--one prescribed using the vision tester, the other pair prescribed using a standard Snellen chart.

Seventy percent of the subjects preferred the PRIO prescribed glasses. Subjects also reported less eyestrain and fewer headaches when wearing the experimental glasses.

The results weren't due to guessing, according to Nilsen. Only 22 of the subjects correctly identified the PRIO prescribed glasses.

French claims the experimental glasses make a definite difference.

"Five years from now, everyone will have glasses prescribed using this technology. We won't remember when we weren't tested for computer use," she says.

Nilsen presented the results of his research at CHI '95 Conference on Human Factors in Computing Systems. The paper, "Reducing Visual Stress Symptoms of VDT Users with Prescription Eyeglasses," also is available at http://www.lclark.edu/~psych/papers/.

Nilsen recently completed a third study. The experimental tasks were similar to those in the previous study, but this time all subjects shared the same job to further control subject variables. All were technical help-line consultants for a local software company.

"We found the same results," Nilsen says. "Seventy percent of the subjects preferred the PRIO glasses."

Nilsen is exploring further studies involving another 1,000 subjects.


Story Source:

The above story is based on materials provided by Lewis And Clark College. Note: Materials may be edited for content and length.


Cite This Page:

Lewis And Clark College. "New Way Of Prescribing Glasses Reduces Computer Eye Strain." ScienceDaily. ScienceDaily, 5 January 1998. <www.sciencedaily.com/releases/1998/01/980105053738.htm>.
Lewis And Clark College. (1998, January 5). New Way Of Prescribing Glasses Reduces Computer Eye Strain. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/1998/01/980105053738.htm
Lewis And Clark College. "New Way Of Prescribing Glasses Reduces Computer Eye Strain." ScienceDaily. www.sciencedaily.com/releases/1998/01/980105053738.htm (accessed October 21, 2014).

Share This



More Computers & Math News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Japanese Scientists Unveil Floating 3D Projection

Japanese Scientists Unveil Floating 3D Projection

Reuters - Innovations Video Online (Oct. 20, 2014) Scientists in Tokyo have demonstrated what they say is the world's first 3D projection that floats in mid air. A laser that fires a pulse up to a thousand times a second superheats molecules in the air, creating a spark which can be guided to certain points in the air to shape what the human eye perceives as an image. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Apple Enters Mobile Payment Business

Apple Enters Mobile Payment Business

AP (Oct. 20, 2014) Apple is making a strategic bet with the launch of Apple Pay, the mobile pay service aimed at turning your iPhone into your wallet. (Oct. 20) Video provided by AP
Powered by NewsLook.com
Google To Protect Against Piracy ... At A Cost

Google To Protect Against Piracy ... At A Cost

Newsy (Oct. 20, 2014) Google is changing its search-engine results to protect content producers from piracy — for a price. Video provided by Newsy
Powered by NewsLook.com
What We Know About Microsoft's Rumored Smartwatch

What We Know About Microsoft's Rumored Smartwatch

Newsy (Oct. 20, 2014) Microsoft will reportedly release a smartwatch that works across different mobile platforms, has a two-day battery life and tracks heart rate. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins