When one pair isn’t enough: task glasses for the workplace and hobbies. Optometry Australia, National Gallery of Canberra. Conference theme: “Growing your occupational optometry skillset”.
Digital eyestrain is a collective term for symptoms associated with using a digital device, for example, headaches, sore eyes, blurred vision and neck/shoulder pain (1).
Blue light and digital eyestrain
Many types of digital devices use light emitting diodes (LED), with short wavelength (blue light) LED components, to light the display. Exposure to blue light can disrupt our sleep and very high levels can damage the eye’s retina (see May 2019, June 2019 and May 2021 editions of this newsletter). This knowledge about blue light has led to concern that blue light could also cause digital eyestrain.
Blue light filters are an almost-transparent coating applied to spectacle lenses to reduce the amount of blue light transmitted to the eye. Depending on the brand, they reduce blue light transmission by up to 43% (2) and are sold with the promise that they can increase your visual comfort when you use a digital device.
Blue light filters are different to blue blockers, which are spectacles that reduce blue light transmission by up to 100% and have an orange coloured tint.
Do blue light filters prevent digital eyestrain?
Researchers have shown that digital eyestrain symptoms can occur after 20-30 minutes of computer work. However, there is no evidence that blue light causes digital eyestrain. For example:
Palavets and Rosenfield (3) found that placing a blue blocker filter over a computer display to stop blue light reaching experimental subject’s eyes had no effect on subjects ratings of digital eyestrain. The same researchers also found that accommodative (focussing) effort was no different with and without the blue blocker filter (3).
Nor is there evidence that blue light filters prevent digital eyestrain. For example:
In experiments where subjects were asked to complete a computer task while wearing spectacles fitted with a blue light filter or a placebo (no blue light filter), there was no difference in their accommodative effort (4) and no difference in their ratings of digital eyestrain symptoms (4,5) with the various filters or placebo lens.
What should you do if you experience digital eyestrain?
It’s a sign of modern times that people spend long hours looking at their devices, so perhaps it is not surprising that many people also experience eye and vision discomfort by the end of the day.
If you experience digital eyestrain symptoms then it is important to have your eyes examined, wear up-to-date spectacles or contact lenses, take regular rest-breaks from your work, and check that your device and work area are set-up correctly for comfortable vision (6) .
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Conferences + Seminars.
Here are the conferences and events that I will be speaking at in 2022:
The visual ergonomics of working from home. Optometry Australia, National Gallery of Canberra. Conference theme: “Growing your occupational optometry skillset”.
Previous seminars and conferences from the past few years:
Future-proofing a “Visual Ergonomics and Visual Display Use” technical report for an international audience. Human Factors & Ergonomics Society of Australia, Virtual Conference, 8-9 November 2021.
Visual Ergonomics in a virtual world: Lighting assessments conducted in cyberspace. International Ergonomics Association Triennial Congress. Virtual Conference, based in Vancouver, Canada. 14- 18 June 2021.