Photograph by BLEACHER + EVERARD
By Barry Santini
The futurist, Alvin Toffler, correctly predicted that information would become the main currency of our daily lives. Doubt it? Consider how we look for answers to simple questions: “Where’s that movie playing, and what time does it start?” “I wonder if my husband’s flight has been delayed?” “Who knows about that new restaurant that just opened in town?”
For common questions like these, we no longer seek out the newspaper, a telephone or a friend for answers. We reach for one of these new information access points: a cell phone, tablet or a computer. And with ongoing and extensive downsizing, these devices are increasingly mobile. While these devices now seem like obvious choices, what isn’t so obvious is how the use of these devices has quietly increased the visual demands made upon our eyes.
Yet technology has evolved too, in both diagnostics and lens design, and is ready to address these contemporary needs. To remain competitive in this evolving eyewear market, ECPs must understand the science, diagnostics and lens technology needed to properly address the vision problems created in the new age of digital information delivery.
THE VISUAL DEMANDS OF DIGITAL DEVICES
No matter what digital device you choose to use—computer, tablet or cell phone—they all place unconventional demands upon our eyes. Research conducted by lens manufacturers, scientists and schools of optometry has identified several key vision challenges arising from the use of digital devices.
Challenge: Smaller devices, like cell phones, are typically held 2 inches to as much as 9 inches closer to the eyes than traditional books and newspapers.
Reason: The print size and font styles in the smallest screens are more comfortably read at closer distances.
Potential problems: Increased accommodative and convergence demands, both separately and combined, which tax the user’s eye and eye muscles.
Challenge: Tablet devices, with their larger surface areas, deliver unstable levels of brightness, contrast and glare.
Reason: Varying brightness and contrast levels may elevate the eye’s normal sensory response, resulting in lower fatigue thresholds. Depending on the nature of the screen, i.e., “e-ink” vs. “retina” displays, or matte vs. glossy glass surfaces, problems can arise from unwanted glare and unfavorable contrast. Most devices compound these problems by not providing one button access for altering contrast and brightness. And although matte screens can reduce annoying environmental reflections, they may also reduce optimum contrast. Also, the portable nature of these devices means a display found to work well in one room or environment may be less satisfactory in another.
Potential Problems: During typical, extended multi-hour use, non-optimal brightness or contrast levels may fatigue the viewer, reducing productivity.
Challenge: Computer displays are often positioned with their screen centers at eye level, with keyboards overly displaced from the display.
Reason: Desktop computers are increasingly formatted as all-in-one affairs, featuring large screen sizes. These screens are often more comfortably viewed at longer distances, which increases the distance between keyboard, mouse and display.
Potential problems: Standard desk heights place these larger displays too high for comfortable viewing, resulting in undesirable head, neck and back posture positions in order to maintain natural eye depression angles. Straight-ahead viewing also lacks the cyclo-rotation that accompanies normal, depressed angle near focus, and this compounds eye tracking and eye synching issues. Larger keyboard-to-screen distances may also create accommodative “bounce” problems. Further, non-optimal placement or intensity of overhead lighting can add additional layers of distracting glare which exacerbates visual fatigue.
Eyecare professionals should keep in mind the following characteristics shared by all digital devices:
- Display fonts are of pixelated origins which, along with size and serif-style, make letter recognition more difficult.
- The latest LCD and LED-based displays emit or reflect disproportionate amounts of blue light, further compounding the eye’s difficulty in maintaining optimal focus and tracking.
- The frequency of the eye’s blink reflex is reduced in near tasks and combined with lower levels of indoor humidity, can compound dry eye problems and degrade subjective acuity.
- Compared to conventional printed media, digital devices place additional accommodative and vergence demands on users’ eyes.
DIAGNOSING PROBLEMS POSED BY DIGITAL DEVICES
It’s easy for patients and even eyecare professionals to chalk up common eye symptoms, such as intermittent blurry vision or eyestrain to being overworked. Not only would that be wrong, but it would also present a simplistic and incomplete picture of what factors are impacting your patient’s overall eye health. According to The Vision Council’s new report on “Keeping Your Eyes Safe in a Digital Age,” all ECPs should be on the lookout or inquire about any of the following visual symptoms or complaints associated with the use of digital devices:
- Intermittent blurry vision
- Dry eye
- Red eye
- Neck and back pain
- Difficulty with vision at night
- Overall eyestrain
BEYOND ONE SIZE FITS ALL
With the arrival of the information age, more and more folks from every walk of life have embraced and integrated digital devices into their daily routine. But in order to use digital devices most effectively, we first have to stop viewing lens solutions in traditional “one size fits all” terms. This means going beyond thinking “general-purpose” progressive and single vision lenses are good enough. Fortunately, market penetration and acceptance of free-form, digitally-enhanced lens technology could not have arrived at a better time. The unrivaled ease with which lens designers and vision researchers can engineer custom software-based designs to meet today’s vision demands has never been better.
ECPs have gradually become comfortable with recommending prescription eyewear featuring lenses designed for computer usage. But being classed as occupational design has somewhat pigeonholed these lenses, as ECPs mostly reached for them only where strong complaints are heard within a work environment. Today, with the arrival of easy access to Wi-Fi and cellular networks, more and more folks have accepted and integrated digital devices into their daily routine. Eyecare professionals should begin pointing out how people are increasingly replacing books and newspapers with their phones and tablets to access the information they need every day. The use of these devices therefore impacts both presbyope and non-presbyope, even if they are not looking at a computer eight hours a day. It’s time to move beyond thinking in strictly occupational vs. general use terms when making lens recommendations.
The biggest difference in how people use digital devices compared to reading books and newspapers is in the deviation of the angle of their eyes with their head. Most people typically find adopting a smaller eye depression angle more comfortable when viewing the smaller amounts of vertical real estate found on most portable screens. Using a traditional progressive lens design would put their eyes in the middle of the intermediate zone. This is not an ideal situation for cell phones, which are held an average of 4 inches closer than conventional reading distances. It’s also important to note that conventional single vision lenses offer no help in offsetting the increased accommodative demands of these closer distances.
Although adjusting corridor length can help optimize traditional progressives for these situations, what can’t be controlled is what is needed most: the ability to vary the rate of power change within the corridor. Here’s where free-form’s design flexibility can come to the rescue. For both single vision and progressive lenses, engineers have now crafted a new class of “enhanced” designs that are more optimally tailored to the needs of cell phone, tablet, video game and computer users. These lens designs are described in the sidebar “Solutions for Digital Device Comfort.”
WHAT ABOUT THE EMMETROPE?
If an ECP really understands the benefits of the above technologies, they should find it easy to appreciate that both emmetropes and ammetropes will enjoy the greater comfort these lenses and coatings provide. Then it’s time to update the old riddle of “Is Plano an Rx?” to: “Doctor, are you comfortable writing a ‘Plano’ Rx AND prescribing a specific, enhanced product solution for your patients?”
THERE’S AN ‘OPP’ FOR THAT
It’s become almost a cliché to offer “there’s an app for that” to almost any problem one encounters. We are really fortunate to have a myriad of new optical solutions available, both in the exam room and in products properly tailored for problems arising from the use of digital devices. Staying current with the latest technologies also helps you to remain competitive in your local market through increased trust and credibility in your patient’s eyes. By investing the time, money and training to make sure you have all your digital bases covered, you’ll be taking advantage of an important opportunity to help your patients and grow your business.
Solutions for Digital Device Comfort
Besides the revolutionary improvements in sharpness and utility delivered by free-form lens technology in the last few years, we're also fortunate to be poised at the dawn of an era where eyewear solutions, tailored to the exact needs of an individual wearer, will become the norm instead of the exception. Let's take a look at some of the recent developments in both lens designs and coatings optimized for the digital device user:
Enhanced Single Vision Solutions
There is now a substantial evidence of how the excessive near demands made by the use of digital devices can reduce the frequency and amplitude of eye saccades, which has been correlated to decreased reading speed, comprehension and memory. The first wave of single vision lens products designed to address some of these demands feature modest plus dioptric power, in the range of 0.25D to as much as 0.80D. By providing accommodative support to help offset the demands made on our eyes by both closer fixation distances and longer durations of sustained use, these designs might be more properly placed in a new class of lens which promises anti-fatigue, improved relaxation or optimal eye synching benefits. In fact, that's just what the current offerings are called.
Essilor Anti-Fatigue: Among the first type of these lenses on the market, they feature an additional 0.60D of accommodative support. To further reduce annoying lens glare, Anti-Fatigue lenses come standard with premium Crizal anti-reflective coatings. Available in select material substrates.
Shamir Relax: Featuring 0.50D of accommodative relaxing support, Relax lenses also feature all the benefits of improved clarity possible through the sophistication of free-form lens surfaces. Available in all material substrates.
Hoya Sync: Featuring full width application of vertical aspheric lens design, Sync is available in two accommodative support levels: 0.53D - Sync 5 for youngsters, students and young adults, and 0.88D - Sync 8 for those individuals assessed to require greater support. Available in select material substrates along with atoric free-form optimization.
Tailored Progressive Solutions
Most ECPs are already aware of the present lens designs for occupational/computer use. Beyond these, some practitioners have had success customizing progressive corridor length to help computer users avoid eyestrain and uncomfortable head, shoulder and neck strain. Today, lens manufacturers are recognizing that free-form technology can allow even more tailored solutions:
Shamir In Touch: A progressive lens design which offers a tailored progressive corridor optimized for users of digital devices. Featuring a corridor gradient that rises in power 25 percent faster, In Touch delivers optimal intermediate power where users of digital devices need it most. This also provides more comfortable viewing by reducing the angle of eye depression by as much as five degrees. Available in all material substrates.
Zeiss Individual 2I and 2N: As noted, Zeiss engineers have crafted two additional Individual progressive designs, optimized for either intermediate (I) or near use (N). Available in select material substrates.
Digital Devices and Blue Light
With the increasing use of ever brighter fluorescent, LED and OLED lighting technologies, our eyes contend with increasing indoor levels of blue spectrum wavelengths. Not only proven to be more difficult for the eye to focus, blue light levels emitted from the latest digital displays also increase scatter and eye fatigue by reducing optimal contrast. Current offerings in top-tier, anti-reflective coatings have been engineered with this in mind, and it is not difficult to notice the characteristic blue reflex color of some premium offerings like Zeiss Purecoat and Essilor Crizal Sapphire UV. Special mention should be made for a new offering from Nikon, called SeeCoat Blue, which features a 10 percent overall reduction in the blue energy spectrum from 400 to 450 nm, compared to a standard, green-reflex AR.
Zeiss Gunnar Optics
Unique in the arsenal of vision products designed for the challenges of the new media, Gunnar Optics eyewear is primarily being marketed to people who are extensively using computers and digital devices on a daily basis—whether or not they have a prescription. Gunnar Optics combines several new technologies to help users with their digital devices:
Lenses featuring fractal technology: Close-fitting lenses deliver a wide, optically undistorted view, free of frame-border distractions. Combined with a wraparound profile, the close fit of Gunnar Optics helps to reduce tear evaporation. Fractal technology also provides modest amplitude of accommodative support.
Blue-filtering Amber Tint: Reduces unwanted visual scatter from excessive display and other environmental light sources.
Anti-glare Coatings: Eliminates distracting lens reflections, maximizing contrast.
Barry Santini is a New York State licensed optician based in Seaford, N.Y.