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how glasses correct your vision?

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Have you ever wondered why you have to start each day by putting on your glasses? If you wear glasses, you already know they help you to see better, but you may not know exactly how they correct your vision.
asked 6 days ago in Health by smyadmin

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Understanding how glasses correct your vision begins with a basic understanding of how the eye works. At the back of the eye is the retina, a layer of cells that react to light. The reaction is sent to the brain, and the brain translates the activity of the cells into an image, or the thing that you see. Eyeglass lenses are curved pieces of glass. The curvature of the lens bends the light rays as they approach your eye. This helps the rays focus on your retina, instead of behind or in front of it.There are two main types of lenses used in eye glasses or contacts. Convex lenses, curve in slightly, are used for nearsighted people. This bends the light towards the bottom and top of the lens, thus pushing the focal point back towards the retina. Farsighted individuals need a concave lens. The light that passes through a concave lens is bent towards the center, pushing the focal point forward. The goal of the correction is to have the focal point hit the retina exactly where it should for ideal vision. The degree of the lens's curve changes with the strength of the prescription.
answered 6 days ago by Rico
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In a person with uncorrected vision, their cornea and lens refract (bend) light that enters the eye, to focus a sharp, clear image on the retina. Now if your eyes are not shaped properly (spherically) and are either too short or too long, your point of focus will not be on the correct spot within the eye, causing certain images, objects and/or distances to become blurry. These types of visual imperfections can be corrected with a custom built lens that compensates for any errors in the shape of your eyes. There are three different shapes for these lenses; cylindrical, convex and concave. Concave lenses correct nearsightedness, convex corrects farsightedness and cylindrical usually corrects for astigmatism. Glasses can also be made out of different materials. Glass lenses can be more scratch resistant; however they can sit rather heavy on your face. High-index plastics are about 20% thinner, which can make them most ideal for higher prescription. Polycarbonate plastic are the strongest available, which makes them preferred for active children.
answered 6 days ago by Grillparzer
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Have you ever wondered why you have to start each day by putting on your glasses? If you wear glasses, you already know they help you to see better, but you may not know exactly how they correct your vision. Eye glasses work in the same manner whether they are for nearsightedness or farsightedness. The eye glass lens is curved so that it bends the light rays that hit your eyes so you can see images clearly.

Understanding how glasses correct your vision begins with a basic understanding of how the eye works. At the back of the eye is the retina, a layer of cells that react to light. The reaction is sent to the brain, and the brain translates the activity of the cells into an image, or the thing that you see.

When your eye looks at something, the light rays come together, or focus, inside your eye. In someone with perfect vision, the rays focus directly on the surface of the retina. The image also must shrink, and it needs to be curved, because the retina is curved. The pupil and cornea are responsible for shrinking, focusing, and curving the image. If they have any irregularities, your vision will be blurry.

Nearsighted individuals cannot clearly see things that are distant. This happens because the light rays come into focus in front of the retina. Farsighted individuals have the opposite problem. The shape of their eyes causes the light rays to come into focus behind the retina, causing things that are near to them to be out of focus. Some people have blurry vision due to an astigmatism, or a condition where the curvature of the eye is irregular, creating a second focal point within the eye. All three of these common problems can be corrected with glasses.

Eyeglass lenses are curved pieces of glass. The curvature of the lens bends the light rays as they approach your eye. This helps the rays focus on your retina, instead of behind or in front of it.

There are two main types of lenses used in eye glasses or contacts. Convex lenses, curve in slightly, are used for nearsighted people. This bends the light towards the bottom and top of the lens, thus pushing the focal point back towards the retina. Farsighted individuals need a concave lens. The light that passes through a concave lens is bent towards the center, pushing the focal point forward. The goal of the correction is to have the focal point hit the retina exactly where it should for ideal vision. The degree of the lens’s curve changes with the strength of the prescription.

If you wear glasses or contact lenses, you are in good company. Around 160 million people in the United States alone wear corrective lenses to improve their vision. From that statistic, it seems that perfect vision is a rare occurrence. So when you get up tomorrow, put your glasses on with a little better understanding about how they work.
answered 6 days ago by Andy
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You probably know dozens of people who wear eyeglasses—you may even wear them yourself. In fact, it’s estimated that only four out of every ten people have perfect vision, which means that 60% of Canadians are in need of some form of vision correction. And yet, despite this statistic, most of us who wear glasses or contacts everyday don't really understanding how they work.

Below are a few facts on the science behind how glasses and contacts correct your vision.

how do glasses and contacts correct your vision D3BFFBA56B30

How Do Your Eyes Focus?
At the very back of your eye is the retina, which is composed of a series of complex cells. The retina reacts to light and transmits that information to the brain, letting you see a final image. The retina does this by making the image smaller (not unlike how a digital camera previews an image), focusing the light, and curving the image to match the natural shape of your eye. To further help in the process, the eye has a lens between the retina and the pupil (the "peep hole" in the center of your eye that lets light into the back of the eye) and a transparent covering known as the cornea (the front window).

What Makes Vision Blurry?
When light enters into the eye, the cornea and lens work together to focus the image onto the retina. The retina then sends the image to the brain, which is essentially how we see. When you suffer from nearsightedness, farsightedness, or astigmatism, it means something is wrong with either the lens or the cornea. When you see an optometrist , they will determine your prescription based on how much more light needs to be bent in order to give your brain a focused image. And just like that, the blurriness is gone when you put on your glasses or contacts.

How Do Corrective Lenses Work?
Corrective lenses are designed to help the lens and cornea create a clear image for the retina to send to the brain. The prescription in your glasses adjusts how the light hits the eye so that, in combination with the lens and cornea found in your eyes, your vision is clear. Eyeglass lenses bend the light more or less, depending on the strength of your prescription.

How Do Internal Freeform Lenses Make a Difference?
Internal Freeform lenses use technology that fuses the prescription onto the back of the eyeglass lens using three-dimensional digital software (as opposed to other lenses, in which the prescription is added to the front of the lens). Because the prescription is closer to the eye it offers a wider field of view and much less distortion. This technology also takes into account the individual movements of your eyes, how far your lenses sit from your eyes, and the natural curvature of your face.

The best way to determine what type of corrective lenses you need is to schedule an appointment with an optometrist. Remember that your vision often changes over time, which is why it's recommended by Health Canada that you get an exam at least once every two years (and once a year for children, the elderly or individuals suffering from health problems).

To get your vision tested and learn more about how your eyes work, book an appointment with an FYidoctors location near you.

answered 6 days ago by Linda R
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Do glasses ever fix your vision?
I think I may need glasses. I can see things that are close up just fine, but things that are far away get blurry. I can make them out, but they're blurry. I think I'm about to head up to Walmart for a free eye exam.

My question is, if I do get glasses, will they strengthen my eyes, or will I be stuck wearing them for the rest of my life?

I don't like the idea of needing glasses for the rest of my life at all. Is there anything I can do to improve my "farsight"?

Ok, I just got back from an eye exam.

Apparently I have like 20/21 vision in my left eye and 20/60 vision in my right eye.

My numbers are:

Right SPH: -1
Right CYL: -0.25
Right Axis: 175
Left SPH: -0.25
Left CYL: -0.25
Left Axis: 130

The doctor said I had pretty eyes, but I think she just wanted me to buy glasses. She was cute though.
answered 6 days ago by Chaotic42
your stuck with them for life

and your eyes will most likely continue to get worse as you get older

i first got mine when i was a junior in HS ~17, i just needed them to drive with, when i was a soph in college ~20 i needed them all the the time, im now 23 and my Px just changed cause they got worse, i have contacts so its not that bad
Nope. In fact, unless things have changed, only hard contact lenses even prevent your vision from getting worse.

FYI, there are contact lenses you can wear during the night that shape your eye and then you don't have to wear anything during the day. I believe they are called CRT lenses.
they are corrective lenses
that doesn't mean they correct your eyes, they correct your eyesight
so that you can see
your eyes go bad and stay bad or get worse, they don't get better, unless you get them lasered
I've had the same pair of glasses since high school...the first time i got glasses. im a jr in college now and my vision is the same. I just got another eye exam and my vision hasn't changed at all...but im still going to wait a couple more years b4 i get lasik.
Considering that the dioptic adjustments of lenses merely accommodate the refractive anomalies of your own lens, it should follow that there's no way to correct it, as others have said. I guess if you were able to move the lens of your eye closer or further from the retina, you could reduce your myopioa and hyperopia, respectively.
I've had glasses since 7th grade. My entire family has glasses, including my 2 brothers. Unfortunately, I have terrible vision. I got hard contacts a few years ago, but they are a pain to wear. God, I cannot stand them. But I still wore them for 2 years. I'm hoping to get Laser Eye Surgery when I'm around 25 or so (I heard that was the best age?). I just wish it'd be a tad bit cheaper...

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