Value Village ／ Health
This answer is a draft. It stays unpublished until legal review and source verification are complete.
The longer we look at screens, the more eye strain comes up as a topic, in Japan as everywhere else. If you work in Japan, it helps to know that the national guideline from the Ministry of Health, Labour and Welfare (MHLW) frames the countermeasure as time, not light. That changes what a sensible routine looks like.
MHLW, *Guidelines for Occupational Health Management in Work with Information Equipment* (Notice Kihatsu 0712 No. 3, 12 July 2019):
Blocking blue light is not positioned as a main countermeasure in this guideline. Research into its effects is still ongoing, and no settled conclusion can be said to exist.
[Verify] Check against the full text of the guideline. The same guideline also gives reference values for lighting levels and viewing distance.
As above, managing time is the core of the countermeasure. Do not rely on blocking alone.
The guideline does not say "when tired"; it says "do not exceed one hour". Break off before you feel tired.
The greater the difference in brightness between the screen and its surroundings, the greater the load is generally described to be. Do not make the room extremely dark.
Different products have different purposes. Check the label and, if needed, ask the pharmacist at a drugstore (Matsumoto Kiyoshi, Welcia, etc.).
If you have changes in vision, pain or headache, or if symptoms persist, do not judge for yourself. See an ophthalmology clinic (眼科, ganka; covered by Japanese health insurance).
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https://www.mhlw.go.jp/content/000539603.pdf
https://www.nichigan.or.jp/
https://www.e-healthnet.mhlw.go.jp/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
This article is not meant to diagnose or manage any specific medical condition. If you are worried about your health, see a doctor rather than relying on your own judgement.
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