Abstract: when the light beyond 5 meters enters the eye, the refractive stroma of the eye does not need to be adjusted, and the light can be focused on the retina. When the light within 5 meters enters the eye, the eye can properly adjust the refractive stroma to focus the light on the retina. The closer the target is to the eye, the greater the adjustment effect.
myopia can you see clearly by narrowing your eyes?
nearsighted friends have had such experience. When they want to find something and see things clearly without glasses, they unconsciously narrow their eyes. In this way, they seem to be able to see clearly. What is the basis for this phenomenon? Let’s answer it for you today.
for people with normal vision,
when the light beyond 5 meters enters the eye, the refractive stroma of the eye does not need to be adjusted, and the light can be focused on the retina. When the light within 5 meters enters the eye, the eye can properly adjust the refractive stroma to focus the light on the retina. The closer the target is to the eye, the greater the adjustment effect is.
due to long-term ciliary muscle spasm, fatigue or eye elongation, normal refractive adjustment is difficult to focus light on the retina. Passive use of some abnormal methods can focus light on the retinal membrane. Narrowing your eyes and looking hard is one of them.
the principle that myopic squint can see clearly
1. Squinting can reduce the surface of external light entering the eye, so as to focus a little hole.
2. The contraction of orbicularis oculi muscle can make the eyelid exert a certain pressure on the cornea and force the cornea to change the curvature surface, so as to change the refraction of light entering the eye and form a focus when reaching the retina.
3. The contraction force of the orbicularis oculi muscle acts on the sclera adjacent to the ciliary body in the front of the eye, which compresses the ciliary body, further contracts the ciliary muscle fibers stimulated by pressure, relaxes the ciliary ligament, and makes the front of the lens more prominent, so as to increase the diopter of the eye and achieve retinal focus.
can achieve a little temporary retinal focus under these three conditions, but this effect cannot last long, and the result of long-term effect will deepen the diopter of the eye and produce astigmatism inconsistent with the corneal refractive rate, which is more unfavorable to the eye.
often squint at things, which will also make the surrounding muscles too tense and cause fatigue symptoms such as acid swelling and pain of the eyes. Therefore, myopic patients with the habit of squinting should get rid of this bad habit and treat early or wear glasses with appropriate diopter.