How Glasses are Manufactured including design and production
Glasses are considered by some people as something quite trivial and just a fashion statement, yet for the millions of people worldwide that wear them they are absolutely crucial. These delicate vision accessories have a very intricate and detailed manufacturing process.
What is the Origin of Glasses?
The history of glasses is quite fascinating. The history of glasses can be traced back to the 13th century in Italy. Back then glasses were very simple tools used primarily by scholars and monks, who used them to help with reading. These early glasses were very basic, with glass lenses fitted into frames made from wood, bone, metal and other materials that could be used to old a glass lens.
Over the centuries, glasses have continued to evolve from the rudimentary designs that were hand-held in front of the eyes, to being able to "clip" the glasses on to the nose (interestingly these were called Pince-nez), and then the 18th century brought some major developments in terms of design and functionality, looking more like the glasses we recognise and wear today, with frames starting to have side arms resting over the wearer's ears. From being solely used to help with reading, glasses have really expanded into vision correction, protection, and more recently fashion.
What are Glasses Made out of?
Modern day glasses primarily consist of two components: the frame and the lenses. Frames are made from a large variety of materials, each chosen of course for its unique advantages. Traditional materials like metal and plastic are always popular, but there's been a big rise recently in terms of using lightweight and flexible materials like titanium, stainless steel and carbon fibre, and even more recently, the use of sustainable materials such as cotton based acetate and even recycled marine plastic.
Lenses, originally made from glass, have also seen a recent push towards lighter, safer and more durable materials like high-index plastics, polycarbonate and Trivex.
How are Glasses Frames Made?
A pair of glasses will normally begin life with a design concept. Using online software, a digital prototype is made and all points of the virtual model are inspected. After finalising the design, the manufacturing process comes next.
Plastic frames are usually made by injection moulding where molten plastic is injected into a mould in the shape of the frame. Metal frames are most likely to be made with a casting process, where molten metal is poured into a die that resembles the frame design.
The last phase involves polishing and hand-finishing the frames to eliminate any irregularities and make sure it’s as smooth as can be. Finer details like adding any brand logos, detailing on the frames and / or any colour detailing will be done in this stage.
How Long do Glasses Frames Take to be Made?
The duration for frame production can vary quite a lot based on the material being used, the complexity of the design and how exactly it is being manufactured. A machine-made frame could be made in a mere few hours. On the other hand, a bespoke, handcrafted frame could take several weeks.
How are Glasses Made to a Specific Prescription?
Creating prescription lenses is really a meticulous process. It all starts with an optometrist determining the exact corrective requirements for each eye. This prescription is sent to a lab, where technicians start making the lenses.
A Lens starts as an optical-grade disc that’s a little larger than the finished lens. This blank disc is inserted into a lens generator, a machine that then grinds the required prescription into the lens.
The lenses are then polished, smoothing them all over so that any roughness from the grinding process is taken away. Using the frame as a template, lenses are then cut down to perfectly fit the frame.
After shaping, lenses can be treated with additional coatings depending on the wearer's needs. These coatings could include anti-reflective layers, UV protection or a scratch-resistant layer.
The last step is inserting the lenses into the frames, a careful process to ensure they fit perfectly and provide the vision correction needed.
The art and science of making glasses is quite detailed and has improved drastically over the years. From the moment the design is created to the final stage where lenses are carefully fitted into the frame, each step in creating a pair of glasses is crucial.
So, the next time you slide on your glasses, remember the intricate journey they've been through before reaching you. It's not just about clear vision; it's about appreciating the craftmanship, history and technology behind creating every pair of glasses out there.
Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 3 Sep 2023, Last modified: 24 Sep 2023