How Do Eyeglasses Work?

With over 75% of Americans needing vision correction, glasses have become integral to the everyday routines of many. But how exactly do they help us see better, and why are they favored over other corrective methods?

Today, we break down the interesting science behind glasses, and how they're able to transform our vision from blurry to crystal clear.

A brief history of prescription glasses

Glasses have been around for centuries, but they haven't always existed in the form we're all familiar with now. The earliest known record of specs dates back to the 13th century, and they were essentially two magnifying lenses connected and perched on top of your nose.

By the 18th century, temple arms were created so that the lenses would stay put when worn, which eventually led to the development of wireframes. Shortly after, innovations in eyewear began to accelerate, with some notable milestones being the introduction of 'scissor glasses' that could be tucked neatly into one's pocket, Benjamin Franklin's invention of bifocal lenses, as well as the conception of cylindrical lenses for astigmatism.

Come the industrial age, manufacturers started exploring different frame materials and shapes, which gave rise to the fashionable styles we all know and love now, such as the cat eye, browline, and oversized silhouettes.

How do human eyes work?

Our eyes are complex and hardworking organs that allow us to receive and process visual detail, which in turn enables us to make sense of our surroundings. It begins with light passing through the cornea, which bends light to help our eyes focus. Next, the light enters our eyes through the pupils, with the irises controlling the amount of light coming in. This is also what causes our pupils to dilate or contract depending on the time of the day.

After that, the lens will fine-tune and adjust the light depending on the distance of the object in focus, letting the appropriate amount of light enter the nervous tissue at the back of our eyes (a.k.a. the retina). When the light finally hits the retina, special cells called photoreceptors transform the light into electrical signals to be sent to the brain. The brain then processes these signals into the images you see.

How prescription lenses correct vision problems

Now that you know how normal vision takes place, let's get into some common conditions that cause eyesight problems and how glasses can fix them:

Nearsightedness

Also known as myopia, nearsightedness is a type of refractive error that makes distant objects appear blurry. It occurs when the shape of the eyeball is too long from front to back, making light focus in front of the retina instead of on it. Myopia can be congenital or developed anytime from childhood to adulthood and is often linked to one's lifestyle choices (e.g. prolonged time spent on close-up activities such as looking at computers and other smart devices, as well as reading)

Luckily, myopia can easily be corrected with single vision lenses, which bend the light properly to reach the correct spot on the retina. You may notice that the lenses are a little thicker around the edges, and are distinguished by a minus (-) sign on your prescription.

Farsightedness

Scientifically called hyperopia, farsightedness is the exact opposite of nearsightedness, and causes nearby objects to look blurry. Hyperopia happens when the shape of the eyeball is too short from front to back, which makes light focus behind the retina instead of on it.

Just like myopia, hyperopia can also be congenital or developed at any point in one's life. A lot of children are born with farsightedness, but this usually disappears as the eyeball develops and increases in length. However, hyperopia will persist if the eye doesn't grow enough, thus continuing into adulthood.

This refractive error can also be corrected with single-vision lenses designed for farsightedness, which are thicker at the center and distinguished by a plus (+) sign on your prescription.

Astigmatism

Astigmatism is another common eye problem that causes your vision to look blurry or distorted. It occurs when your cornea has a slightly different shape than normal, making the light bend differently as it enters the eye. Astigmatism can be hereditary, but it can also be developed later on in life or after an eye injury or surgery.

To correct astigmatism, special cylindrical lenses are needed to correct the way the light hits the retina. Aside from the usual spherical (+/-) prescription, you'll also have a cylinder (the amount of astigmatism correction you need) and axis (the specific lens angle needed to correct your astigmatism) measurement to account for.

How to get a prescription for glasses

When correcting vision problems such as refractive errors, it's important to get as precise of a prescription as possible to achieve perfect vision. To do so, the first step would be to consult your go-to eye doctor and take an eye exam. For this, you'd want to acquaint yourself with your family's history, such as whether your parents or siblings have eye conditions or diseases that may have an impact on eye health.

Following this, your doctor will then assess your eyesight through a variety of visual acuity tests. If you'd like to know more about what to expect during an eye examination, we've got an in-depth blog post you can check out.

Finding a glasses frame that fits you

Just because you need glasses to correct your vision doesn't mean that you'd have to compromise on style. Today's frames are far from boring, and come in so many different shapes, sizes, colors, and materials that'll bring out your best self.

When picking out frames, some factors you'd want to take note of are your face shape and natural coloring. Having a good understanding of your features will help you figure out which types of frames suit you the best and make your search for the perfect pair a lot easier. We at Door2USA Prescription Glasses also have a handy virtual try-on that you can check out, so you can see how our glasses look on you from the comfort of your home.

Look and see your best with Door2USA Prescription Glasses

And there you have it! We hope this blog was able to answer all the questions you may have about prescription glasses. They may take a little time to get used to at first, but nothing beats being able to see the world clearly.

For a wide selection of trendy, functional, and affordable glasses, check out our extensive collection of frames here at Door2USA Prescription Glasses.

Frequently asked questions

1. How often should I go for an eye exam?

While recommendations may vary depending on age and medical history, most adults are advised to have an eye exam every two to three years.

2. How long does it take to adjust to new glasses?

It can take anywhere between a few days to a couple of weeks to get used to your glasses, especially if you're a first-time wearer or have just switched to a higher prescription.

3. Do you need a prescription to order glasses?

Some types of glasses, such as readers, can be purchased over the counter without a prescription. However, those with farsightedness or more than one refractive error will need a doctor's prescription to have the lenses customized to their specific needs.