The History of Corrective Lenses
People have been using tools to help them see clearly since at least 60 A.D.
Roman philosopher Seneca is recorded to have used a glass globe of water to magnify text, while Emperor Nero would use a magnifying emerald to see gladiator fights better. We no longer need to resort to using water bowls or gemstones, and it’s pretty cool to see how far we’ve come in vision correction since then.
Corrective Lenses Evolving Over the Centuries
In the 10th century in Europe, monks made the next leap forward in corrective lens technology. They needed to be able to see tiny details to do their beautiful illuminated calligraphy, and they discovered that polished domes of transparent quartz worked very well. They called these “reading stones.”
Another couple of centuries would pass before anyone would try attaching reading stones to wearable frames for easier use. We don’t know the identity of the first person to do this, though we often credit Florentinian man Salvino D’armati.
Glasses for the Lower Classes
The earliest spectacles could only be made out of expensive materials like crystal, making them a status symbol for the wealthy but far too pricey for anyone else to afford. As literacy rates skyrocketed across Europe following the invention of the printing press in 1440, demand increased for affordable reading glasses. Production became cheaper when they began using glass for the lenses instead of expensive crystal.
Prescription Lenses and Foldable Frames
Glasses in the next couple of centuries were still pretty limited. The frames had to perch on the nose or be held with a handle, and there was only so much fine-tuning glass blowers could do with the lenses. Correcting for specific refractive errors wasn’t really possible (imagine wearing someone else’s glasses). Then, in the 1700s, temples (the portion extending past the ear) were added and glasses became hands-free.
We give Benjamin Franklin credit for inventing bifocals, which was also when hinges were introduced, making glasses foldable for compact storage. Eye doctors were making headway in tailoring lenses to patients’ specific needs, including the invention of cylindrical lenses for astigmatism in the early 1800s. Finally, Herman Snellen, a Dutch eye doctor, invented the “big E” chart, standardizing vision correction across the field of optometry.
