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The Digital Realm
Alan Saks | 26 March 2017
The digital lens category is a focused spin-off of occupational or office lenses. With the massive swing to the use of digital devices over the past decade – by young and old – spectacle lenses designed specifically for this use are evolving fast. It pays to be up to speed on the various offerings, and aware of the different aspects of these lenses. Unlike traditional reading glasses, progressives and the more traditional occupational lenses often prescribed for presbyopes, digital lenses are ideal for a broader range of patients. We are also seeing specially designed contact lenses entering this arena, however for the purposes of this article we will limit the discussion to spectacle lenses.
Who, What, When, Why & How
Digital lenses can be prescribed for presbyopes using digital devices within the typical near and intermediate zone. Additionally these lenses are increasingly being developed, marketed and prescribed for non-presbyopes. The goal for non-presbyopes is to reduce accommodative demand and in doing so, reduce symptoms of asthenopia (eyestrain) and improve ocular comfort, accuracy of focus and reduce convergence demand. This will generally lead to the ability to concentrate for longer, work more efficiently, improve performance and avoid, or at least delay, the onset of symptoms. These lenses usually incorporate ‘degressive’ or progressive power changes, with more plus for near and intermediate tasks to reduce accommodative-convergence demands. At the same time, a prism may be incorporated in some designs to further improve accuracy of fixation while reducing convergence effort.
As we often see, young people often hold their smartphones and tablet devices at very close, seemingly abnormal working distances of 10-20cm. The accommodative demand at 10cm is a staggering 10.00D while at 20cm it is 5.00D while at a more normal 50cm the accommodation effort required is ‘only’ 2.00D. Experts suggest that we use one third of our accommodative ability and retain two thirds in reserve, so as to be able to sustain prolonged accommodative efforts over the course of a day. It can thus be seen that those accommodating 5.00D or 10.00D will not leave much left in reserve (depending on age). Those over the age of 30 or 40 years will be pushing their eyes to the absolute limit. The result is the early onset of visual fatigue and asthenopic symptoms of sore, red, tired, heavy feeling eyes, headaches, blurred and sometimes double vision. Dry eye and symptoms of a sore neck or back are additional issues that may arise. There is also concern that excessive accommodative input, esophoria and resultant accommodative dysfunction, can spur the progression of myopia.
Blue Light: Potential Dangers
Another important consideration when prescribing digital (and other lenses) and one that has received much, sometimes controversial and sensationalised coverage, is that of blue light and its potential risks and side effects. High energy visible light (HEVL) in the blue-violet spectrum has been shown to be potentially damaging to certain cells in the retina as well as having the potential to disturb the sensitive circadian rhythms, hence potentially affecting sleep patterns. The potential long-term damage to the sensitive macula, in particular, is of concern.
Modern digital devices are regarded as having high outputs of HEVL. Even seemingly innocuous LED lights, now prevalent in our workplaces and homes, have been shown to emit significant levels of HEVL. With long hours spent viewing devices and working under LED lights potentially affecting our sleep patterns and wellbeing, it would seem prudent to block blue light.
With this in mind, many digital lenses incorporate selective blue light (SBL) filters that are in essence, selective bandpass filters that only attenuate a specific 40nm passband in the 415-455nm high energy, blue light region of the spectrum. Of course, the attenuation or filtering range varies between manufacturers.
Get on the Bus, Gus
In general, if we read between the lines, filter out the fluff, focus on the critical stuff and common threads, we can come to some useful conclusions.
Prescribing SBL filters seems to be all about potential for harm or prevention of potential harm and it is probably best to err on the side of caution. There doesn’t appear to be any significant downside to prescribing these additional filters so why wouldn’t we?
The respected Harvard Medical School provides this advice when it comes to blue light.
- Use dim red lights for night lights. Red light has the least power to shift circadian rhythm and suppress melatonin.
- Avoid looking at bright screens beginning two to three hours before bed.
- If you work a night shift or use a lot of electronic devices at night, consider wearing blue-blocking glasses or installing an app that filters the blue/green wavelength at night.
- Expose yourself to lots of bright light during the day, which will boost your ability to sleep at night, as well as your mood and alertness during daylight.
Other Benefits of Digital Lenses
In this increasingly competitive eye care world, it is essential to find ethical ways to increase revenue and turnover. Proactively prescribing digital lenses and filters is one of those ways. For very little extra effort in terms of time and resources, the increased dollar value of these specialised lenses can significantly enhance the bottom line and ongoing viability of a practice.
It’s time to get on board. Don’t miss the boat… Check out the lens and filter offerings from our featured suppliers. Contact the companies for information and arrange for specialised training of you and your staff to get a better understanding of their lenses as well as prescribing and dispensing tips.
Hoya Indoor Lenses
Hoya offers a wide range of indoor lenses for prolonged visual tasks to help alleviate eye strain and even reduce fatigue. These include the latest Hoyalux iD WorkStyle V+, offered in three design variations to suit each wearer’s visual requirements. Each design has a specific definition to achieve optimal depth and width of vision, depending on your patients’ needs.
Hoyalux iD WorkStyle V+ Close
Hoyalux iD WorkStyle V+ Close is designed for people with specialist hobbies and professions that require high levels of concentration and perfection. Wearers benefit from the widest possible near area, while still being able to view perfectly at intermediate distances up to one metre.
Hoyalux iD WorkStyle V+ Screen
Hoyalux iD WorkStyle V+ Screen is designed for people that require smooth and sharp depth and width vision from near distances up to two metres. This makes it ideal for computer work.
Hoyalux iD WorkStyle V+ Space
Hoyalux iD WorkStyle V+ Space is suitable for people performing activities where the focus is a little further than a computer screen, offering reliable distance vision up to four metres and above, while still having crystal clear vision on the screen.
The majority of your patients are looking at digital screens for more than five hours per day*, resulting in eye fatigue and digital eye strain. Dynamic Sync for non-presbyopes will reduce eye fatigue and eye strain, provide relaxed vision in all directions and at all distances, and comfortable, clear vision all day long. Dynamic Sync is available with two boost add power options; up to +0.53D and up to +0.88D.
Diamond Finish BlueControl
Hoya BlueControl is a coating that neutralises harmful high energy blue lights, protecting your patients’ eyes while offering more comfortable and relaxed vision and a more natural colour perception. BlueControl is offered in combination with Hoya’s unsurpassed Diamond Finish anti-reflection coating, offering up to five times more scratch resistance than conventional multi-coats.
Contact: Hoya sales consultant.
*2015 & 2016 Digital Eyestrain Reports, The Vision Council
CR Surfacing Anti-Fatigue
The Signature Anti-Fatigue lens is a free-form lens that’s designed to give welcome relief to hardworking eyes. Aspheric optimised distance combined with nominated low additional powers offer the wearer easy adaption and instant relief. Ideal candidates for this lens are patients who experience eye strain and visual fatigue with reading, computer work and other near tasks.
The Anti-Fatigue lens is now available in a stock lens with the added protection of Satin Blue. Known as the Anti-Fatigue ST, this lens incorporates protective coatings to shield the eyes from harmful blue-light providing greater comfort and clarity when using a screen.
Contact: CR Surfacing Laboratories (AUS) 03 8795 9111
Essilor Digital Lenses
Essilor offers eye relief for patients stuck in front of computers and devices. Eyezen, for patients under 40, offers distance vision if needed and three levels of support for the wearer’s accommodation: 0.40D, 0.60D and 0.85D.
For the over 40s, Essilor offers Varilux Digitime in three styles: Digitime Near for computer use, smartphones and reading; Digitime Mid for the computer, around the desk, and near; and Digitime Room for the computer and across the office. By providing the patient’s working distance from their nose to their computer screen, Varilux Digtime provides a minimum depth of field within +/-15cm of the screen distance. Add Crizal Prevencia to Eyezen and Varilux Digitime to reduce the specific blue light band, and enhance contrast and comfort.
Contact: Essilor Account Manager
Nikon’s e-Life series is a comprehensive range of lens selections designed to meet today’s growing digital lifestyle.
There are four options available: DigiLife provides a wider intermediate progressive lens for early or confirmed presbyopes; Home and Office provides an extended intermediate lens with wider indoor vision for reading glass wearers; Soltes Wide delivers an extended near lens that’s one grade up from your typical reading glasses; and Relaxee is a single vision lens with twin zone technology (far and near vision) to help patients who are non-presbyopic but experience eye-strain and visual fatigue. Add SeeCoat Blue UV – a coating option for screen contrast.
Contact: Essilor Account Manager
Hastings Optical Supplies
Hastings’ occupational lenses allow wearers to maintain a natural posture by providing maximum comfort for all office and device requirements.
Office Reader lenses, for intensive use of near and intermediate vision zones, offer the widest near and intermediate visual areas with a minimum lateral astigmatism and are available in all digressions from 0.75 to 3.00 (pictured). Pure Office lenses are soft designs with a comfortable transition between distances, reducing the adaptation time and greatly expanding visual fields. Acomoda is ideal for wearers aged between 18 and 45 years old, with high quality features in the near zone to reduce digital eyestrain and help protect visual health over the long-term.
Hastings Optical's PVBlue AR Coat reduces the blue light associated with screen based devices for even greater comfort.
Contact: Hastings Optical (AUS) 02 6584 3577
Blue Guardian Lenses
The blue blocking agent embedded into Blue Guardian lenses blocks high energy blue light from entering the eye and helps protect against harmful UVA and UVB energies. These lenses are recommended for adults using electronic devices as well as children as they are more susceptible to the effects of blue light.
Also available from Opticare is Skeye Blue Multicoat, a special lens coating that provides greater contrast and better protection while using digital devices.
Contact: Opticare (AUS) 1800 251 852
Lutina is a new lens material (1.6 and 1.67 indices) that cuts out the UV and high energy visible blue (HEV) light to reduce oxidative stress and potentially reduce damage to the lutein and macular pigment caused by free radicals.
Blue Colour Coat (BCC), recommended when a Lutina option is not available, protects the eyes by cutting out the blue light believed to cause the flicker and glare from computer screens and electronic devices. BCC can be used on 1.7 and 1.76 materials and combined with P-UV coating.
Night Coat is designed for use at bed time to support sleep by cutting the blue light around 480nm. All of these lens materials and coatings can be used on Tokai Optical’s anti-fatigue (Relaxus), digital computer lenses (Largo), and indoor progressive lenses (Presso).
Contact: Tokai Australia (AUS) 07 3012 9422
The Zeiss Digital Lens is designed to provide clear, crisp, comfortable vision all day while reducing eyestrain and minimising the physical strain associated with digital device use, even after a long day using a smartphone or tablet. These lenses carry a 100 per cent Zeiss tolerance-guarantee.
Zeiss DuraVision BlueProtect reflects part of the high-energy blue light coming from sources such as LEDs, as well as TV, computer and/or tablet screens. This coating reduces the transmission of hazardous blue light in the spectrum of 380–440 nm (blue light hazard) while keeping the high transmission level above 460 nm to safeguard circadian rhythm regulation and natural colour vision.
Zeiss DuraVision BlueProtect offers the best-in-class properties of Zeiss anti-reflective coatings for superior hardness, anti-static properties and ease of cleaning.
Contact: Zeiss Account Manager
Bonastar blueEase coating can increase contrast, comfort and focus while minimising eye fatigue and visual stress for anyone who spends long periods in front of a computer. It is proven to help cut the blue light emitted from PC screens, mobile phone displays and LCD TV screens, and minimise glare for sharp and clear vision. This advanced lens coating technology can reduce blue light which causes flickering, ghost effects and the ultraviolet light reflected from the back of the lens. It can be prescribed with Bonastar single vision 1.60 stock, single vision grind, Digital Office, free-form progressive lenses.
AFPro is designed for single vision wearers under 45, who complain about tired eyes at the end of work days. This new anti-fatigue progressive technology can build variation in power at the near zone to assist the normal binocular function of eyes during working with computers, thus relieving patients from digitally induced eye strain and other visual stress.
Eyezen, the innovative digital screen protection lenses created by Essilor, is now available from Bonastar.
Contact: Bonastar (AUS) 02 9310 1688
Transitions adaptive lenses block 100 per cent of UV A and B, and also filter harmful blue light outdoors and in.
Transitions Signature VII lenses block at least 20 per cent of harmful blue light indoors – up to two times more than standard clear lenses – and more than 85 per cent outdoors. They are completely clear indoors and darken outdoors, making them ideal for people who spend equal amounts of time indoors and out.
For the more active wearer, Transitions XTRActive help provide more protection everywhere they are needed, blocking at least 34 per cent of harmful blue light indoors and 88–95 per cent outdoors. Transitions XTRActive are the darkest everyday lenses available in the range and even darken behind a car windscreen.
Contact: Transitions Account Manager
Rodenstock's suite of Ergo lenses has three designs to suit different working distances. In each design the degression varies, dependent on the add, to give clear vision in the designated area.
The Ergo Book is ideal for short distances vision of between 40 to 60cm, while also allowing up to 1m with vertical movements of gaze. It’s perfect for laptop computers and tablets.
The Ergo PC gives the widest area of clear vision at a medium distance up to approximately 1.20 m and allows a monitor to be seen in total clarity, without strain and with an ergonomic head and body posture.
The Ergo Room allows for relaxed vision indoors, free from fatigue and with comfortable vision zones from the reading area up to 4–5m.
Contact: Rodenstock Account Manager
the increased dollar value of these specialised lenses can significantly enhance the bottom line and ongoing viability of a practice