Computer Vision Correction

omputer Vision Correction

Working for long periods on a computer is a demanding visual task. Daily, millions of Americans use a computer for hours at a time, both at work and at play. Many of them routinely experience symptoms of  headache, fatigue, blurry vision, scratchy eyes, or pain in the shoulders, neck or back.  Our eyes and brain react differently to characters displayed  on a computer screen than they do to characters printed  on paper. Computer images are less distinct than printed characters, may have perceptible flicker, and usually have less contrast between characters and the background. Computer users must rapidly switch focus from keyboard to monitor and vice versa; this constant refocusing can also contribute to symptoms.

What are computer glasses?

Computer glasses are prescription glasses that are specifically designed to wear when doing computer work. They allow you to focus your eyes comfortably on a computer screen, which is usually farther away than reading material is held.

General purpose bifocals and trifocals are not designed for computer work. Bifocals 
force the wearer to tilt the head back in order to focus on the screen, while 
looking through the lower portion of the bifocal lenses. While conventional trifocals 
allow a more normal head posture, they generally have too small an area for viewing 
the computer screen and the visible dividing lines can be a significant distraction.

Which kind of computer glasses are the best? 

There is no one type of computer glasses that fits all or is the best for everyone. Visual ability, personal preferences of the computer operator, the type of work, the distance between the computer user's eyes and the monitor, and lighting design in the workplace should all be taken into consideration when selecting computer glasses.

Lens design and lens options vary significantly from manufacturer to manufacturer. It's always best to make your final selection of computer glasses based upon the advice and recommendations of your eye doctor; however, all of the options listed below 
have proven to be beneficial for computer users.

Progressive Addition Lenses

Surveys conducted among persons working long hours with computers revealed that Progressive Addition Lenses (PALs) were the lenses of choice. These modern lenses 
have more than just the cosmetic advantage of "no lines." They provide all the benefits of bifocals but add the feature of continuous clear vision at all distances, including 
mid-range distance (arm's length). Several lens manufactures have introduced PALs designed specifically for computer use. These specialized PALs allow an even wider 
field of view for near and intermediate working distances than standard PALs.

Anti-Reflective coating 

Today's advanced Anti-Reflective (AR) coatings eliminate bothersome reflections from overhead lights and computer monitors. AR coatings not only reduce reflections but increase the amount of light transmitted through the lenses to the wearer's eyes. It 
may seem strange but AR coated lenses actually appear clearer than uncoated clear lenses...sometimes appearing to be nearly "invisible."

Natural light sources (windows) can be especially bothersome in the workplace. When a window is located over the wearer's shoulder, natural light striking the back surfaces of the lenses bounces directly into the wearer's eyes. Since outside light levels are quite high, the intensity of these reflections can be even greater than reflections from light sources within the workplace. An AR coating placed on the back surfaces of the lenses eliminates these "outside" reflections as well.

High Index Lenses

Modern technology has created lenses that bend light differently so that stronger corrections are thinner than when made in conventional materials. Such lenses are 
called "high index". High index materials can drastically reduce the thickness and weight of  prescription lenses. Lens thickness can sometimes be cut by as much as 50% by simply using a higher index material and choosing an appropriate frame. High index materials are more shatter resistant than traditional plastic and will improve the appearance of any prescription. 

Note: High index lenses bend light to a greater degree so an anti-reflective coating 
is especially recommended to maximize their performance and cosmetic advantages.
 

In Conclusion

• Computer glasses provide a wide field of view so that the user can clearly read both their computer screen and closer printed material.
   
• Anti-glare coatings can be used to eliminate bothersome reflections from windows, 
  overhead lights and other nearby computer monitors. 
   
• Use of high-index lens materials keeps lenses thinner and lighter in weight.
   
• Computer glasses give the most natural, comfortable vision possible.
   
• Computer PALs provide clearer vision for reading and viewing screens at intermediate distances better than any previously designed lens.

If you're one of the millions of people who use a computer on a regular basis, be sure to ask your eye doctor about "computer glasses" the next time you have your eyes examined or replace your current prescription.