Preludes' Blog of Words: Who Invented Glasses?

Who Invented Glasses?

Nowadays we don't really think of short (or long) sightedness as any sort of disability.

It's commonplace to the point of near invisibility. CBS statistics state that approximately 61% of the population needed some form of sight or reading aids in 2012 (as compared to 57% in 2001). The number only increases as the population weighs in with an increasingly towards older generations and as our lives become more affixed to our screens and books.

Take away your glasses and contact lenses, however, and it's soon very clear just how vulnerable you are.

Usually I'm reminded of this when I go to the hairdressers. They sit me down, I take my glasses off and instantly I'm plunged back into a world of vague fuzzy shapes. I put blind trust in what the hairdresser is snipping away at. While we make small talk I look straight ahead and try not to squint, and I try to give friendly eye contact when I can't actually see her eyes. There's always something unsettling in holding a conversation with a face that, for all intents and purposes, has more in common with Slenderman's than something human.

I find it hard not to think how difficult life would be without my glasses when I sit in that chair, and how much they enrich my life.

So how was life like for people before glasses were invented? And who were the people in history who worked to give the precious gift of sight?

There is debate about just how developed ancient eye-correction was.

According to the scholar Edward Rosen, the first known reference to a pair of eyeglasses was in 1305 when Friar Giodarno di Rivolta remarked 'It is not yet twenty years since there was found the art of making eyeglasses which make for good vision, one of the best and most necessary the world has.' However, the inventive use of lenses and the like to correct faulty vision potentially much older.

Astriophanes (approx 450-385 bc) mentions plan-convex lenses and globes of water that were used to see, and the Roman Seneca is said to have read through a globe of water. However, the use of these aids were not so widespread as to stop a prominent Roman in 100bc from complaining in a letter that he lamented his poor eyesight preventing him from reading. He instead had to rely on his slave reading out any text for him.

While it is not confirmed what its use was, the Nimrud Lens is the oldest known lens found in the world and is dated to somewhere between 4,500-3,500 years old. It's entirely possible that people could have used this to aid them in reading. It is thought that the Romans, Babylonians, Greeks and even Vikings all could create similar lenses of varying quality (thought it is suggested that the vikings instead had these manufactures in the Byzantium empire).

The Nimrud Lens

Eyeglasses as we now know them were likely created in medieval times.

While the gradual wearing of sight is a common ailment of people as they grow older, it is likely that the increase in reading and scholastic learning in the Medieval period drew more attention and inventiveness to the problem of long-sightedness. In 1289 di'Popozo wrote that "I am so debilita-ted-by age that without the glasses known as spectacles, I would no longer be able to read or write. These have recently been invented for the benefit of poor old people whose sight has become weak"

Monastic populations were often the focus for the development of eyeglasses. For example, in the 14th century, it is thought that Friar Alessandro reverse-engineered earlier sight-aids and transformed them into a useful eyeglass, proceeding to share the invention with the population. This was a significent shift away from the norm of invention: in the times before copyrighting craftsmen endeavoured to keep their methods a secret in order to better profit from them, so Alessandro's act of kindness allowed for a great leap forwards in the technology.

Art at the time begins to depict people wearing spectacles and they were gradually associated as a status symbols for learned men, though of course this was dictated to by the shifting fashions of the time.

It wasn't until the 16th century that concave lenses were created for the short-sighted rather than the long-sightedness that is a usual symptom of age. Perhaps the most famous customer for these new short-sighted glassed was Pope Leo the 10th, who used to wear them while he was hunting. Sometime between 1760 and 1780 Benjamin Franklin began experimenting with even fusing the two, creating verifocals.

While the efficiency of glasses were dependant on the sophistication of glass-making technology, perhaps the biggest design challenge was how on earth to keep them on your head!

Many spectacles were designed on a hinge that would perch on the edge of the nose like scissors or could be held up to the face. In the 17th and 18th centuries it was common to have glasses on a stick to hold up opera-style, and ribbons were commonly used to affix glasses more tightly to the face in order to get a better focus from them. In 1781-89 glasses with sliding extension temples were created, but these didn't see widespread use until the 19thc.

Nowadays, the commonest style is through temple bars that hook around the ears but, even so, Opthalmologist Melvin Rueban insisted that these spectacles were 'one of technology's best examples of poor engineering design'.

Modern glasses designs can be adjusted through heating and which curve around the ear, supported by adjustable nose-pads and springs, though any glasses user could quickly tell you that these are still far from perfect.

Nowadays, technology has advanced to the point of potentially erasing the need for frames all together.

Spectacle frames are and, for the foreseeable future, will continue to be the most popular option for vision correction due to their practicality and relative(!) cheapness. However, we are now lucky enough to have the options of contact lenses and laser eye correction to cure short or long sightedness.

Contact lenses were suggested as early as 1845 by Sir John Herschel, but it was F. E Muller who first put them into practice by blowing a glass lens over the eyeball of a man whose lid has been destroyed by cancer. This contact lens was said to have lasted until his death 20 years later. While further experiements and studies commenced, it wasn't until the 1940s that a full variety of contact lenses became available to the public and widely used.

By 1964 some 6 million people in the US wore contact lenses, with 65% of which were female. Given the vulnerability of spectacles to rather severe criticism in fashion, and the close link of traditional female identity with her looks, this is rather unsurprising.

In the 1970s the development of the excimer laser offered a ground breaking alternative to both spectacles and contact lenses - what if short or long sightedness could actually be cured?

Stephen L Trokel used it to experiement on the eyes of cadavers and then living animals, seeing how their corneas could be altered for the better. In 1988 Trokel was lucky enough to have a willing human participant: a 60-year old woman who was due to have her eye removed due to a malignant melanoma asked if they would like to experiment on her. Trokel's colleague, Marguerite MacDonalD performed the first photorefractive Keratectomy on the lady that year. By the early 1990s the procedure was approved in Canada and the US.

In 1999 the development of wavefront technology allowed doctors to map out a patient's prescription on the unique corneas and by 2002 100% bladeless surgery was finally possible.

Sight correction has come a long way in our history and it can only get better

Currently scientists are even on the verge of helping the blind to see.

In 2009, following a work accident, the builder Martin Jones was left blind but, luckily, with one eye still intact. Groundbreaking surgery, carried out by the surgeon Christopher Liu, allowed one of Martin's teeth to act as a replacement lens. While admittedly quite a grisly procedure, it allowed Martin to see his wife after 12 years of blindness. As the tooth is part of Martin's body, there is a far smaller chance of his body rejecting it than if it was made form synthetic materials.

How Martin Jones gained his sight back

Oxford University's smart glasses are designed to help near-blind users by amplifying what little available sight they have.

The device takes 3d objects and alters the images, making them into bright defined silhouettes.

One user, Lyn Oliver, was diagnosed with Retinis Pigmentosa in her early 20s which gradually led to extensive vision loss. She relies on her guide dog Jess to navigate, but using the glasses made this significantly easier.

“If Jess stops, the glasses can tell me if she’s stopped because there’s a kerb, there’s something on the floor or it’s roadworks, and it’ll give me a sense of which way she may go around the obstacle.
‘If people are stood outside a shop talking, they often go silent when they see me and watch me walk past. But they’ve disappeared as far as I am concerned. Have they moved? Have they gone inside the shop?
“There’s a sudden stress about avoiding them. The glasses help remove this layer of stress and they do it in a way that is natural to the person using them. After taking them off I was missing them."
Here are the smart glasses in action: