[Why?] Why do we see better when we wear glasses?

When eyesight worsens, many people wear glasses.

Then, the scenery that was blurry until then becomes surprisingly clear.

But, if you think about it for a moment, isn't it strange?

Why does just placing a simple transparent lens in front of your eyes make you able to see?

Are glasses improving your eyesight?

Are they healing your eyes?

Is there some special mechanism inside the lens?

Actually, none of these are quite right.

Glasses are not healing your eyes.

By changing the direction of light, they focus it where it should be.

In this article, I will explain why you can see better when wearing glasses, based on scientific evidence and in a way that is easy for beginners to understand.

First, the conclusion

The reason you can see better when wearing glasses is that

the lens changes the direction of light so that it focuses on the retina.

In other words,

glasses are not restoring your eyesight, but rather

adjusting the path of light.

First, let's learn how we see

To understand how glasses work, you first need to know how the eye sees.

The eye is often compared to a camera.

Just as a camera lens gathers light to take a picture,

the eye also has parts that act as lenses.

These are the

• cornea

• crystalline lens

.

Light entering from the outside passes through the cornea and the crystalline lens,

and reaches the

retinaat the very back of the eye.

When light focuses perfectly on this retina,

a clear image is sent to the brain,

and objects appear sharp.

Why does vision become blurry when eyesight worsens?

As introduced in the previous article,

in cases of myopia, the eyeball can become slightly elongated from front to back.

When this happens,

light focuses before it reaches the retina.

By the time it reaches the retina,

the light has already spread out,

which is why distant scenery appears blurry.

In short,

having poor eyesight means

that the focus of light is misaligned

.

What do glasses do?

This is where glasses come in.

The lenses in glasses

bend light

to perform their function.

When light

enters a different material, such as glass or plastic, from the air,

its direction of travel changes slightly.

This is called

refraction

.

Glasses use this refraction to

adjust the light so that it focuses exactly on the retina.

In other words,

the scenery that was blurry

becomes clearly visible once again.

Are the lenses different for nearsightedness and farsightedness?

Actually,

the lenses used change depending on the condition of your eyes.

For nearsighted people

With nearsightedness,

light focuses in front of the retina.

Therefore,

a concave lens, which is thinner in the center, is used.

A concave lens

has the effect of spreading light slightly outward.

As a result,

the focus moves backward,

allowing it to align on the retina.

For farsighted people

With farsightedness,

light tries to focus behind the retina.

So,

a convex lens, which is thicker in the center, is used.

A convex lens

has the effect of gathering light.

As a result,

the focus point moves forward,

and aligns on the retina.

Does wearing glasses cure your vision?

Here,

many people have a misunderstanding.

"Does wearing glasses every day cure my eyes?"

Actually,

glasses do not cure the eyes themselves.

They do not have the function of returning the shape of the eyeball to its original state,

or treating myopia.

They are merely,

adjusting the way light travels,

to make things easier to see.

Therefore,

if you take off your glasses,

things will look blurry again.

What is "prescription"?

Glasses have,

a "prescription".

Diopter refers to

how much light needs to be bentto focus.

The stronger the myopia,

the more the light needs to be adjusted.

Therefore,

the diopter strength also increases.

The reason for measuring vision at an ophthalmologist or optical store is

to find the diopter that is right for each individual.

Is it true that wearing glasses makes your eyesight worse?

This has been said for a long time, but

current research shows no strong scientific evidence that wearing properly prescribed glasses causes myopia to progress.

Feeling like your prescription has become stronger than before

is likely not caused by the glasses,

but rather that the myopia itself has progressed.

Rather than enduring a state where you cannot see well,

it is safer for daily life to use glasses that suit you.

Why can glasses sometimes make your eyes tired?

“I can see now, but my eyes feel tired…”

Have you ever had that experience?

The cause for that is

• The prescription is incorrect

• Staring at things up close for a long time

• Dry eyes

• Looking at computers or smartphones too much

are some possible causes.

In other words,

while glasses can help you focus,

they cannot prevent all eye strain.

Summary

The reason things become visible when you wear glasses is that

the lenses refract light and adjust it so that it focuses on the retinais the reason.

Glasses serve the roles of

• changing the direction of light

• focusing on the retina

• making blurred scenery easier to see

as their function.

On the other hand,

glasses do not cure nearsightedness itself.

When you understand how the eye works,

you can see that the glasses you use casually every day actually hide precise scientific mechanisms.

📚 Related Articles

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👀 [Why?] Why does eyesight get worse? It turns out that the eye 'stretching' is the cause.

We explain the relationship between smartphones, nearsightedness, and vision loss in a way that is easy for beginners to understand.

📱 [Why?] Why do our eyes get tired when we keep looking at smartphones?

We introduce the real reasons why eyes get tired and scientifically backed measures you can take starting today.

Next time, we will bring you

[Why?] Why do we see better when we wear contact lenses?

. Stay tuned!

Thank you for reading until the end.