For Your Eyes Only: How Are Glasses Made?

You may wear glasses every day, but have you ever stopped to think about how they’re made?

We go for an eye exam with an optometrist and place an order, and before we know it, our new pair of glasses is ready for us. We put them on and go about our day feeling more in control because we can see clearly. The quality of our lives has improved yet we don’t give our eyewear any further thought.

So how are glasses made? As it turns out, they’re precision-engineered, meticulously tested, and finished with a final human touch.

Let’s explore the manufacturing process that goes into making those glasses to the exact prescription you need to see clearly. You’ll develop a new appreciation for their role in your life.

Where Do Glasses Come From?

The history of glasses is a little murky, but as far back as the Middle Ages the scientists of the time knew that if you look through a glass sphere, it acts like a magnifying glass, making writing bigger and easier to read. Around the 13th century, monks in Italy were wearing the first prototypes of what we would recognize as a pair of eyeglasses today. Monks were the scholars of the day and they needed to be able to read well, often by candlelight.

Back then, they only had simple single-vision or reading glasses. The frames were made from wood or leather and the heavy lenses were made from glass or a crystal stone.

Sometime after that, convex and concave lenses and multifocals — bifocals or even trifocals — were invented. Then much later, contact lenses were developed. Thankfully, corrective eyewear has become a lot cheaper and more accessible over the centuries.

How Are Prescription Eyeglasses Made?

Around 79% of adults in the U.S. now use some form of vision correction, mostly eyeglasses. That’s a lot of glasses!!

Luckily, how glasses are made has come a long way or we could never keep up with producing all those glasses. We now have machines that can make eyewear to exacting standards, and materials that are far more versatile and hard-wearing.

Whereas high-index lenses — for high prescriptions — were once thick and heavy, requiring heavy frames to match, the latest polycarbonate lens materials allow them to be much lighter. And instead of bifocals with hard lines, we now have progressive lenses, which make the transitions between the different focal fields much smoother and less noticeable.

Yet despite all these developments, the same basic elements are still used to make our glasses: the frames and the lenses.

To find out how glasses are made, let’s start with the frames that hold the whole thing together.

Making Your New Glasses Frames

Although some eyeglass frames are made with stainless steel, most are some form of plastic frame, very often cellulose acetate. This comes in a flat sheet and the parts of the glasses are precision-cut from it, including the temple arms and face fronts — the rims, which hold the lenses, plus the bridge between them. The face fronts can be cut in various shapes, like round, rectangular, or cat-eye, to suit different face shapes.

The frames are then tumbled and polished by machines to make sure they’re perfectly smooth before hinges are applied and the temple arms connected. And that’s just the first part of how glasses are made.

Making Your New Eyeglass Lenses

The most common corrective lens materials these days are glass or polycarbonate plastic. Plastic lenses tend to be tougher than glass lenses, which are more likely to break and damage your eyes.

The next step of how glasses are made begins with a lens blank, which is a piece of lens material. One side of the blank is flat while the other has the curvature that your prescription needs. The optical center — the exact spot that sits over your pupil — is marked. Then the lens is protected with tape and using a computer, the back of the lens is cut to correct for your specific needs, for example, farsightedness, nearsightedness, presbyopia, or astigmatism.

The lenses are then polished, often using a fining machine and sandpaper, to make them as smooth as possible. Then they’re ground into the exact shape that’s needed for the frames you’ve chosen. The edges of the finished lenses are polished and beveled to make sure they fit perfectly into the grooves in the frames.

Then, depending on the order you placed with your optician, the lenses may be dipped in a solution to coat them. Common coatings make the lenses scratch-resistant, polarized, or anti-reflective. If you want computer glasses, they’ll receive a blue-light coating. And if you ordered prescription sunglasses, they’ll be dipped into the appropriate tint to give them the color you’re looking for.

Finally, the frames are slightly heated so the lenses can be inserted — which is done by hand — without breaking anything. This process is known as glazing.

As the whole process of how glasses are made has to follow guidelines set by the Food and Drug Administration (FDA) and the American National Standards Institute, quality control is critical. Workers check for flaws like chips and scratches all the way through the process and the prescription is also confirmed. This ensures that only a perfect pair of glasses is dispatched to the wearer.

How Are Stock and Semi-Finished Lenses Produced?

Both stock and semi-finished lenses (which will eventually hold your prescription) are created using a cast. If the lenses have special features like UV absorption, those will be added at this time and injected into the lens material.

For glass, the elements are combined and heated so that they can be shaped into lenses before being ground with a diamond grinding tool.

How Are Plastic and Glass Bifocal Lenses Produced?

When producing glass bifocals, an additional glass will be added to the original glass lens. This is done by grinding and polishing the back of the lens and then melting the new lens into the original. Finally, the combined lenses are polished so that the surface is smooth.

For plastic bifocal lenses, the process is more straightforward and involves curving the plastic lens to create a near field of vision that is separate from far distance.

How Are Multifocal Lenses Made?

Progressive lenses have three fields of vision. They are prescription glasses that correct near vision, intermediate vision, and distance vision. A special grinding machine gives these lenses a specific design.

To create them, manufacturers continually tweak the material until they are ready to be mass-produced and fitted with specific prescriptions.

Creating the frames, lenses, and lens coatings that correct your vision is an involved process. Finding well-made glasses is essential — it’s the only way to enjoy crystal-clear vision and unlimited style at the same time. Luckily, you can find both at Pair.

Where to Find Well-Made Glasses

Now that you know how glasses are made, you may be looking for your next pair of perfectly made glasses. Look no further than Pair Eyewear. Our frames are made from cellulose acetate, with impact-resistant polycarbonate lenses.

We have a range of Base Frames so you’re bound to find one that fits your face shape. Use our Virtual Try-On feature to see what works best for you.

Then, to keep things interesting, you can also choose one or more Top Frames from our huge and stylish collection. Top Frames are only 2 mm thick, making them extremely light. They attach magnetically to your Base Frame, so you can switch up your look from day to day — or even from moment to moment, if you choose.

We cater to a range of prescriptions, from single-vision and readers to progressive lenses. Or if you’re simply looking for some style, you can go with non-prescription lenses. You can also choose to add a blue-light filter or light-responsive coating, so your glasses darken when you go outside. If you need sunglasses, start with the right Base Frames for those. Our sunglasses are 100% UVA and UVB-resistant.

Add a glasses case to keep your eyeglasses safe on the move or, if you have several Top Frames, a Top Frame case to keep in your purse or a wall hanger for your room at home. And make sure you keep your lenses crystal-clear with a microfiber cleaning kit. After all, it’s all about seeing clearly.

So How Are Glasses Made? With Great Care and Skill

The next time you visit your eye doctor for your regular eye care appointment, take a moment to appreciate what goes into making your pair of eyeglasses.

Consider how far they’ve come, from the days of leather and crystal stones to our modern versions. Imagine the frames being crafted from a piece of raw material, then the lenses being cut, polished, and precision-engineered to match your prescription. And then the final assembly is done by hand, so you end up with the perfect pair of glasses for you.