How do we know coloured overlays for computer screens help with screen fatigue?
We’ve written an in-depth White Paper that charts the history of eye strain from Dante to today.
Current research shows that too much screentime is driving myopia and asthenopia to the point that by 2050, half the global population will be shortsighted.
The research also shows that coloured overlays reduce the excitation in the brain, caused by bright screens and the colour contrast of digital display screens, reducing the fatigue .
Below you will find the references and bibliography used for our White Paper
We have kept them within context, making them easier to read and understand.
Note: We define myopia as an asthenopic stress response to induced visual repetitive stressors resulting in injury or adaptation to over-exposure to the near or close-up visual demands.
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Is insufficient access to daylight and overexposure to near and close up in early childhood, exacerbated by the prolonged use and/or operation of a standard DSE interface, driving Myopic and Asthenopic Disease in the 21st Century?
Five million adults in the age diverse UK population are functionally illiterate.
The UK prison population alone houses 50% of inmates who are considered illiterate, with a reading age of 11 years or lower.
58% of the UK workforce is suffering from exposure related visual discomfort, (eye-strain)
1 in 3 of the UK workforce is suffering with arguably either inherited or induced myopia.
The economic impact of this in the UK from the resulting presenteeism is estimated by the ONS to be between £36 – 80 billion per year.
Work by Holden et al in 2016  estimates that by 2050, half the world’s population will become myopic.
Other research undertaken in the same year shows that 19%, nearly 1 in 5 teenagers, are currently myopic: a fifty percent increase since the 1960s.
Some, including the WHO are calling this increasing myopia a Global Pandemic.
Eye strain, referred to in the UK as well as in the US as Computer Vision Syndrome.
Myopia, also referred to as near-sightedness or short-sightedness, a condition where objects at a close distance are clear, and in focus, while objects further away appear blurry.
The soft orb in childhood may become elongated or foreshortened due to inflammation of the retina. This elongation causes light entering the eye to be focusedin the wrong place.
Myopia can be a progressive disorder, and is associated with increased risk of retinal detachment, choroidal degeneration, cataracts, and glaucoma.
Perceived causes of myopia
A systematic review undertaken in 2015 by Hsui-Mei Huang et al concluded that more time spent on close-up work activities was also associated with a higher risk of myopia.
Dr Rudolf Virchow in 1869combed the records of German children and found that the longer the child was in school, the worse the eye damage. McNeelyMedicineOnAGrandScale.pdf (uoregon.edu)
In a German study from 2014, the findings again showed that near sightedness was linked to more schooling.
A new understanding of Binocular Vision issues shows that they are possibly the vital component when treating myopia and amblyopia.
Surprisingly, there is no routine test for binocular vision for children in England, but, it is part of the routine testing in Wales, Scotland, and Northern Ireland.
An editorial in Optometry and Vision Development in 2010 by Dominick M. Maino entitled ‘The Binocular Vision Dysfunction Pandemic’, not only mentions the predicted numbers of adults and children with binocular vision disorders for 2010 but also states that, despite the high number, there is a lack of diagnosis and effective treatment routines, or any national health strategy.
Treatment – Standard Range of Eye Exercises
Eighty per cent of learning comes through vision . Small and subtle errors in vision may play hugely damaging roles in this area. American studies have found that numbers of allegedly hyperactive kids were in fact suffering from poor eye teaming.
Historically, binocular vision dysfunction has been treated with patching. Records show this being used in the year 900 AD. Patching treats the eyes as two separate mechanical objects, with one that needs strengthening. Eyepatch – Wikipedia
There has recently been a shift towards vision therapy, where the eyes are treated as working together to form one organ, which works in conjunction with the brain. The aim of the therapy is to strengthen the way the eyes and brain work together Hess and Thompson (2015) to ‘restore binocular fusion and stereopsis with an expected secondary consequence of improved vision of the amblyopic eye’.
An excellent example of vision therapy is the use of the Brock String.
However, in 2019, the American Academy of Ophthalmology produced a literature review, comparing vision therapy to standard patching.
Surgery is another option for correcting strabismus and amblyopia. In 2014 there had been no published research comparing the before and after surgery result in this area for children under the age of seven.
Literature review from 2019, highlighting discrepancies in outcome reporting for treatments.
The role of stress and visual problems.
Stress symptoms in Occular Health – the ICD 10 Index scaling the range of monocular adaptations.
Yet beyond stress – school, lighting, too much screen time, homework and toxic environments and too little time spent outdoors all add to this issue.
In 1996 Merril D Bowan wrote about the effects of stress upon the eyes of children and that stress could change the shapes of the eyes.
Current data regarding stress and the developing brain, and what are called ACE’s – Adverse Childhood Events, show that stress is an obvious area of research for ocular health. Maryland Coalition of Families explain that, with trauma, “the hippocampus (the area of the brain that processes emotion and memory and manages stress) shrinks.
The WHO claim stress “can disrupt early brain development and compromise functioning of the nervous and immune systems.”
The challenges for a child reading off and/or on-screen, with or without an ocular issue, author and dyslexic campaigner Ian Jordon describes the difficulties in his book “The circle of Underachievement”.
“Reading is a multifaceted process that is influenced by psychological, physiological, environmental, sociological and linguistic factors”, (Christian et all 2017).
The impact of computer technology on public health
In 2017/18 statistics show that 88% of UK households owned a home computer: in 1985 it was a mere 13%.
In 2014, Akinbinu and Mashalla published their literature review on the impact of computer technology on health, specifically looking at Computer Vision Syndrome (CVS).
Computer work includes frequent saccadic eye movement, accommodation and vergence, all involving continuous muscular activity. This is due to the screen images being made of pixels, which have bright light at their core, becoming darker at the periphery, causing electronic characters to blur around the edges. The blurring of the edges makes it harder for the eyes to focus when looking at a screen. Findings highlighted within the review show that the human eye finds today’s computerised gadgets difficult to cope with. In many cases the symptoms of CVS occur because the visual demands of the task exceed the visual abilities of the individual to comfortably perform the task.
All symptoms of CVS were found to be worse in those who express anxiety, stress, and depression; who work over 5 hours more than contracted, but take no time off, in other words – presentees. A more recent systematic review  published in 2020 looking at the effects of computer screens and myopia, gives mixed findings, with some reports showing an effect, but others not. The summary of the review suggests further research in this area.
A survey published July 2020 found that many employees would welcome regulations to manage technology and screen time exposure.
Under the 1999 Management of Health and Safety Regulations, employers have a legal duty to assess and protect workers from work related stress. Screen time may soon be added to the list following campaigns by the NHS and Royal Society for Public Health.
Following development of a “Validated Asthenopic Assessment”, we can now differentiate between symptoms linked to Dyslexia and the symptoms predicting visual disruptions presenting in 3D vision loss.
Impact & Management of Day / Work lighting in schools and offices
When looking into the effects of lighting in offices, the majority of papers refer to commercial productivity. Those that do look at ocular health, find that poor lighting has an effect on degree of fatigue, the eyes and on overall health.
Fluorescent lighting and compact fluorescent light bulbs, an energy saving version, are both known to cause eye strain, with symptoms of dry eyes, double vision, headaches, and poor concentration. This is due to their production of an artificial source of ultraviolet (not Blue) light known to cause cataracts and macular degeneration.
Health and Safety International in 2012 produced an in-depth article related to eye health in the workplace
Dr Richard Hobday PhD, Engineer and author of The Light Solution is convinced that poor lighting in schools is triggering myopia.
Ophthalmologist Dr Starr from Weill Cornell Medical College feels children should spend much more time outdoors, suggesting an extra 3 hours a day.
A recent pilot study from China found that schoolchildren and teachers prefer what they call brightly lit classrooms.
Regulations or just absence of compliance?
In 2017, there was a mere a 10% compliance with UK 1993 Display Screen Regulations (DSE) in the UK
UK employers need to act on Occupational Health and Accessibility regulations: a precedent has already been set with Baker v Quantum Clothing in 2011.
UK DSE Regulations were first created in 1993 and amended in 2002 .
Computer glare – both direct and indirect – causes the visual system and muscles of the eyes to overwork.
The HSE Better Display Screen RR 561 work-related ill-health data in 2007, established that 58% were effectively over-exposed to standard unmitigated calibration of DSE interface, and reported suffering work related eye strain.
WCAG 2.1  Is a web content accessibility guideline 2.1 (2018), extending the existing 8878 guidelines published in 2008.
ISO 30071.1 has been developed to reinforce the 1998 PUWER Act (Provision & Use Work Equipment Regulations) assisting the builders of digital products to ensure sufficient adaptability for the 45% of the UK who suffer a disability of some kind, to be enabled to “access” / customise their screen products.
The UK Government 2018 Accessibility Regulations for Public sector means websites are to be accessibility compliant by 23rd Sept 2020.
Interestingly it could be that children are not considered users, and so are exempt from Health & Safety occupational health protection.
The consequences of the predicted ocular pandemic, that of half the global population experiencing poor vision and poor depth perception, will impact on all areas of life; driving, operating machinery, sports activities, work related tasks and even simple actions such as pouring liquid into a cup.
Asian expenditure on laser treatment is skyrocketing as they try to remedy the levels of myopia, with currently  80-90% of children graduating in Southeast Asia being myopic.
What can be done?
Dr Mutti, Professor of Optometry at Ohio State University, in 2010 discussed his then 20-year-long investigation into myopia 
The use of intuitive coloured overlays and tinted glasses has been well documented, but what is evolving is the next generation of “subjective coloured display screen interface optimisation”. This new, objective methodology was developed originally as a Digital Literacy aid for teenagers but is now being developed as a Wellbeing Tool for those in education, as well as for DSE operators in the workplace, to mitigate repetitive visual injuries in an age diverse population which is already coping with poor environmental factors, in addition to personal visual issues.
Colour optimisation and visual stress.
The WHO has adopted the term Asthenopia as a heading for the range of monocular adaptations, conditions or diseases, spanning the non-specific symptoms of discomfort and fatigue of the eyes which cause visual distortions. Visual stress is said to be caused by deficits in sensory input, not by binocular convergence or accommodation, and has also been shown, according to Kriss and Evans (2005), to affect 12-14% of the population and 25% of non – dyslexic children.
Coloured overlays or tinted-glasses.
Beginning in 1958, JJ Jansky Former Assistant at the Paediatric Language Disorder Clinic in New York, mentioned a student who couldn’t read the words when they were printed on white paper, but could when they were printed on yellow.
In 1980, Olive Meares, a New Zealand teacher described the difficulty some students experienced due to visual distortions when reading black text on white paper.
At around the same time, in 1983, Psychologist Helen Irlen began writing about transparent colour overlays to assist with reading difficulty. Allegedly they were unaware of each other’s work in the 1950’s , but were both describing remarkably similar symptoms, and as such, when the symptoms were discussed, they were often referred to as Meares-Irlen Syndrome.
Coloured overlays and tinted glasses have been widely used for those with dyslexia.
Professor Arnold Wilkins describes the theory behind using coloured overlays as that of reducing visual sensory stimulation. In his TED talk he explains how the human brain and eyes were designed for nature.
The next generation of display screen interface optimisation
The key is finding the very specific contrast colour / hue that calms the excitation, that allows reading on-screen to be a comfortable experience while moving the central nervous system toward the parasympathetic model.
Removing or reducing the levels of discomfort will also reduce the risk levels of visual repetitive stress injuries/adaptations, while at the same, being compliant with legislation. This legislation clearly recognises that colour contrast validation of websites is important, and regulation ISO 30071.1 also recognises that display screen interfaces are intrinsically harmful unless adjusted and/or customised for the specific user operator.
SMART Foundation have developed a unique methodology for the optimisation of the DSE Interface which is relatively seamless, interactive, semi-automated and which, most importantly, achieves a more optimal accuracy versus the current subjective or intuitive “best fit”.
The software is a non-invasive and reasonably practicable method for assessing a subject’s overall stress levels, working as a diagnostic tool, as well as effectively identifying the optimal RGB values for their display screen, thereby offering a therapeutic calibration to reduce this predictable eye-strain, whether it be pre-existing or potentially induced and driven by CVS or Screen Fatigue.
Anecdotal evidence has grown, as many participants comment that, “they didn’t know they were under so much stress”, experience emotional relief through shedding a tear or two, together with perhaps either relief or even rage, when they realise how easy it is to read when using a display screen interface which has been personally calibrated for them. The profound realisation that they did not know how hard they have had to work previously, simply to access text.
More research is needed to fully position “public ocular health” and well-being on the educational and economic map. It will take time and commitment for regulations to be enforced, for eye examinations to change and improve, and for a new and improved use of day and work lighting in the built environment of our schools and offices. One small change, however, that of display screen interface optimisation, could make a huge difference to prolonging the public’s eye health. It could improve educational and work lives and strengthen the capacity for life-long learning via access to the IOT, e-learning and simultaneously the increasingly SMART digital economy.
The SMART Foundation is therefore looking for both academic and corporate partners to expand the development of the on-line interactive software, and fund further research into public awareness. We wish to be able to use our existing patented software, as a foundation on which to build and develop the next generation of AI driven biometrics screening. Our aim is to eliminate, once and for all, the ambiguity of received knowledge surrounding the health benefits of day light. Finally we want to promote ‘colour as an effective therapeutic treatment’ for pre-existing or induced binocular vision loss.
We passionately believe in the future of AI driven biometrics screening for display screen contrast interface optimisation. We believe it is the way forward to protect the well-being of DSE operators. In the chain of causation, it could offer children with learning difficulties improved access to text and the opportunity to actively participate fully in learning in addition to reducing the overall ocular health burden, both in the UK and Globally.
We shall not cease from exploration
And the end of all our exploring
Will be to arrive where we started
And know the place for the first time.
T. S. Elliott
 Fan, Q., Verhoeven, V., Wojciechowski, R. et al. Meta-analysis of gene–environment-wide association scans accounting for education level identifies additional loci for refractive error. Nat Commun 7, 11008 (2016).
 Hsiu-Mei Huang, Dolly Shuo-Teh Chang, Pei-Chang Wu.: The Association Between Near Work Activities and Myopia in Children – A Systematic Review and Meta-Analysis. PLoS One. 2015; 10(10): e0140419. Published online 2015 Oct 20.
 Al Jabri, S., Kirkham, J. & Rowe, F.J. Development of a core outcome set for amblyopia, strabismus and ocular motility disorders: a review to identify outcome measures. BMC Ophthalmol 19, 47 (2019)
 Merril D. Bowan. New Speculations on Refractive Error. Journal of Behavioural Optometry, Volume 7(5) pp 1996, 115-122.
 Jordan I. The Circle of Underachievement. 2002, reprinted 7th September 2018. Self-published/Amazon.Help the S.M.A.R.T. Foundation
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