The history of corrective lenses – Now. Powered by Northrop Grumman
If you are reading this sentence, chances are you use corrective lenses like glasses or contacts. After all, Statistical reports that more than 60% of American adults wear prescription glasses. For many people, glasses or contacts are essential for engaging in activities of daily living, such as recognizing faces and objects, reading, driving, and navigating screens. While modern lifestyles have contributed to the need for glasses earlier in life – as explained in the journal Nature – there is a long history of deterioration of human eyesight with age.
The Roman orator Cicero (106-43 BC) lamented that he needed his slaves to read aloud to him. Just a generation later, the Roman philosopher Seneca (4 BC to 65 AD) is said to have used a glass water globe to aid reading. The first corrective lenses were not goggles to be worn on the face, but similar to magnifying glasses that could be held over objects of interest.
This Roman knowledge of magnification would be lost among Europeans during the medieval period, and it might have been entirely lost had it not been for the work of Arab scholars, such as The American biology teacher Remarks.
How do corrective lenses work?
Corrective lenses work by changing the direction of incoming light waves so that an image is focused when it hits the retina at the back of the eye.
Common vision problems include nearsightedness, farsightedness, and presbyopia. Myopia occurs when near objects appear clear, but far objects appear blurry. This happens when the eyeball is too long, causing light waves to focus in front of the retina. Hyperopia occurs when distant objects appear clear, but near objects appear blurry. This can happen when the eyeball is too short so that the focal point of light is behind the retina. Farsightedness can also be caused by presbyopia, which is when the lens at the front of the eye loses its elasticity and cannot adjust to focus properly on nearby objects. Presbyopia often develops in middle age.
Who invented glasses?
Around AD 1000, Italian monks developed and used polished domes of transparent quartz as reading stones. These could enlarge text and correct farsightedness, as explained in the journal Ophthalmology survey.
An unknown Italian inventor developed corrective lenses for spectacles around 1285 AD. Blown glass lenses were set in wooden, leather or animal horn frames. The glasses were then held in front of the face with one hand or clipped onto the nose. A 1352 painting of monks reading and writing manuscripts shows one using a magnifying glass while another wears glasses, according to Ophthalmology survey. At that time, monks were among the only people who learned to read and write. Around 1440, the invention of the printing press made reading more accessible and increased the demand for glasses.
In the 1600s, artisans in Spain added ribbon so that glasses could be looped over the ears. Other notable styles included the monocle (for one eye only), the lorgnette (which was held in front of the eyes with a long handle), and the scissor glasses (which could be folded). In 1730, English optician Edward Scarlette added stiff temples that extended over the ears, which is the most common style today. In 1784, Benjamin Franklin invented bifocals by cutting and assembling convex and concave lenses, which allowed him to see near and far without changing glasses.
Who invented contacts?
Contact lenses are thin corrective lenses worn “in contact” with the eye. They basically work the same way as glasses, according to All about vision: by refracting incoming light so that an image is focused when it hits the retina. For nearsighted people, the lenses are thicker at the outer edges and thinner in the middle, just like concave lenses for eyeglasses. For farsightedness, the thickest part of the lens is in the middle, just like convex lenses for glasses. Contacts can be much thinner than eyeglass lenses because they rest directly on the eye.
“Who invented corrective lenses” is a complex question to answer. Like many scientific discoveries, there were many important steps towards the creation of the first contact lens. Leonardo da Vinci is credited with the concept of contact lenses, as described by lens shop. His 1508 sketches show a person placing their face in a curved glass bowl filled with water to see objects on the other side more clearly. The water would be in contact with the eyes, so technically it’s a contact lens. In 1636, after reviewing the work of Leonardo da Vinci, the Frenchman René Descartes proposed placing a glass tube filled with liquid in direct contact with the cornea to correct vision. In 1801, English scientist Thomas Young used Descartes’ idea to create a 1/4 inch long water-filled glass tube that he attached to his own eye with wax. Despite these brave efforts, the technology just wasn’t there yet.
In 1887, a German ophthalmologist started making glass contact lenses. The lenses covered all available parts of the eye, including the whites. The glass was heavy, no oxygen could pass through it, and wearers could not close their eyes to the lenses. As you can imagine, these lenses could only be worn for a few hours at a time before becoming excruciatingly painful.
In 1936 the first plastic contact lenses were produced which were much lighter and safer than glass contact lenses. However, they still covered the entire eye and were made of a hard plastic that didn’t absorb water or let in much oxygen. Thus, they were only comfortable for short periods.
In 1948, a manufacturing error led to the discovery that contact lenses covering only the cornea (the colored part of the eye) would stay in place while the wearer blinked and looked around. These smaller lenses were much more comfortable. In 1971 the first soft plastic contact lenses were introduced. They were even more comfortable and allowed oxygen to reach the surface of the eye. Today, more than 90% of contact lens prescriptions are for soft lenses. Manufacturers continue to make improvements to eyewear and contacts for health, comfort and style.
More than 700 years after their invention, glasses are perhaps more indispensable than ever. By enabling people to read, write and learn easily, corrective lenses have undoubtedly contributed a great deal to the new technologies being developed to maintain, restore and enhance our senses.
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