Eyes · Myopia · Screens

眼睛 · 近视 · 屏幕

Place · Level 3 · Body Systems

眼是会自己对焦的相机 · 近视=眼轴拉长 (结构性、基本不可逆) · 最强保护因素是户外光、不是少看屏幕 · 蓝光眼镜对眼疲劳证据基本是空的

Connected to · 3

synergy · 1

Morning Light & Circadian
One dose of outdoor light does two jobs: it slows axial elongation of the eye (time outdoors is the strongest-evidence myopia lever we have) and it resets the circadian clock through retinal ipRGCs. Sending a child outside buys both.

cofactor · 1

Vitamin A
Vitamin A is the raw material for rhodopsin, so night vision fails first when it runs short. That line governs dark adaptation, not refractive error — marketing routinely conflates the two.

regulates · 1

Lutein + Zeaxanthin
Lutein and zeaxanthin stack in the macula as filter and antioxidant, protecting the retina against ageing; they cannot shorten an eye that already elongated — macular protection and myopia control are different problems.

How the eye focuses

Stop 1/5

眼睛怎么对焦 · 一台会对焦的相机

Picture the eye as a camera and you've grasped its essence.

Light enters the eye, first through the cornea (which does most of the fixed refraction), then the lens — the lens changes curvature as the ciliary muscle pulls on it, to focus up close, a process called accommodation. Finally, light must focus precisely on the retina at the back of the eye for you to see clearly.

The key to seeing clearly is 'light landing accurately on the retina'. If the focal point falls in front of the retina, distance blurs — that's myopia (nearsightedness); behind it is hyperopia.

Myopia is rising fast worldwide, especially among East Asian youth, and has become a public-health problem. The good news is that its onset and progression aren't beyond intervention — and the genuinely effective intervention (outdoor light) may not be quite what you'd assume (reading or screens less). This island clarifies what structural change myopia actually is, and which of the screen and blue-light claims hold up.

Read story

Educational content, not medical advice — consult a clinician.

Back

Eyes · Myopia · Screens

眼睛 · 近视 · 屏幕

Place · Level 3 · Body Systems

眼是会自己对焦的相机 · 近视=眼轴拉长 (结构性、基本不可逆) · 最强保护因素是户外光、不是少看屏幕 · 蓝光眼镜对眼疲劳证据基本是空的

Connected to · 3

synergy · 1

Morning Light & Circadian
One dose of outdoor light does two jobs: it slows axial elongation of the eye (time outdoors is the strongest-evidence myopia lever we have) and it resets the circadian clock through retinal ipRGCs. Sending a child outside buys both.

cofactor · 1

Vitamin A
Vitamin A is the raw material for rhodopsin, so night vision fails first when it runs short. That line governs dark adaptation, not refractive error — marketing routinely conflates the two.

regulates · 1

Lutein + Zeaxanthin
Lutein and zeaxanthin stack in the macula as filter and antioxidant, protecting the retina against ageing; they cannot shorten an eye that already elongated — macular protection and myopia control are different problems.

How the eye focuses

Stop 1/5

眼睛怎么对焦 · 一台会对焦的相机

Picture the eye as a camera and you've grasped its essence.

Light enters the eye, first through the cornea (which does most of the fixed refraction), then the lens — the lens changes curvature as the ciliary muscle pulls on it, to focus up close, a process called accommodation. Finally, light must focus precisely on the retina at the back of the eye for you to see clearly.

The key to seeing clearly is 'light landing accurately on the retina'. If the focal point falls in front of the retina, distance blurs — that's myopia (nearsightedness); behind it is hyperopia.

Myopia is rising fast worldwide, especially among East Asian youth, and has become a public-health problem. The good news is that its onset and progression aren't beyond intervention — and the genuinely effective intervention (outdoor light) may not be quite what you'd assume (reading or screens less). This island clarifies what structural change myopia actually is, and which of the screen and blue-light claims hold up.

Read story

Educational content, not medical advice — consult a clinician.