The first man in history who wore contact lenses was a German physician August Mueller born in Munchengladbach (1864-1949). He was inspired by his own significant sight defect (approx. -14 dioptres) which he’d had since childhood. His deliberations on the sight improvement resulted in his PhD thesis, defended on 28 February 1889 and titled “Glasses and corneal lenses”.
To create his lens Dr Mueller used casts of dead people’s eyes. Thanks to that he was able to establish the length of the radius of the corneal curve – 7.5 mm – and the lenght of the radius of the scleral curve – 14 mm. Then Dr Mueller ordered three lenses (-14.5, -15 and -19.5 dioptres) from a famous microscope manufacturer based in Berlin, Karl Otto Himler (1841-1903). The lenses were made of thin glass, around 0.3 mm thick, with carefully cut edges. The outer diameter of the lens measured between 15 and 16 mm. Its inner surface, which directly touched the eye, was divided into the corneal part (7-7.6 mm diameter) and the scleral part (13-14 mm diameter).

In 1508 Leonardo da Vinci (1452-1519) in his work The Codex of the Eye was considering a possibility of a sight defect correction by applying a lens directly onto the surface of the eye. He was inspired by an observation made by an English monk, Roger Bacon, who noticed that after putting his face in a glass bowl filled with water he was able to see his own shoulders.

Of course walking around with your face in a water-filled bowl (the right side of Leonardo’s drawing) would result in drowning, even if the eyesight would be temporarily corrected. Because of this, Leonardo tried to construct smaller bowls that would be put on one eye only. The most important conclusion of these experiments was the observation that the spherical surface of a water-filled bowl, which directly touches the eye, can change the optical power of the eye.

In 1637 Descartes continued deliberations on a sight correction by means of a device applied directly to the eye in his work On Means of Perfecting Vision.

Descartes assumed that prolonging the eye with a miniature telescope filled with water and topped with a lens with a curve similar to the curve of the cornea will enlarge the picture visible in the retina, correcting vision at the same time. The telescope would need to be attached to the eye at all times so the cornea would be in constant contact with water – it was meant to neutralize its optical power. Moreover, Descartes provided a possibility to regulate the length of the telescope. Apart from construction issues, a user would need to have both hands busy – one with holding the telescope close to the eye, the other with keeping the lens focused. So it looks like Descartes’ invention wouldn’t find many takers.

In 1977 J.R. Levene from the British Optical Association tried to build a model of the Descartes’ telescope which did not put its theoretical assumptions in practice. It’s worth stressing that Descartes was wrong about the way the lens worked – contact lenses correct vision not by prolonging the eye, but by changing the optical power of the cornea. He was also wrong about the construction of the device.
But an idea isn’t always put in practice.
In the end we owe the first glass lenses to two Germans. The first was Adolf Eugen Fick (1852-1937). In 1888 he published an article, headlined “Contactbrille”, in Archiv Fur Augen Heilkinde. Initially Fick was making casts of rabbit’s eyes and from them he was creating glass lenses with 19, 20 or 21 mm diameter. Then he put them on rabbits for 6 to 8 hours. There’s no need to mention that after this heavily irritating procedure the rabbits had properly red eyes.

After his successful experiments – at least according to Fick as there was no data about rabbits’ feelings on the subject – he made a lens based on a cast of a dead man’s eye and tried to wear it himself for about 2 hours. Together with Ernest Abbe, a co-owner of the Carl Zeiss AG company and an inventor in the field of optics, he created a glass lens, which he called a “glass cornea” with an 8 mm curve in the optical part and a 15 mm curve in the scleral part. He used this lens to treat keratoconus, irregular astigmatism, aphakia and myopia. His experiments were not appreciated by his peers – perhaps due to the fact that the glass cornea helped only 1 in 6 patients and it irritated eyes and caused redness.

Eventually the first contact lens aimed to correct the vision of its inventor were worn by a German physician, August Mueller, in 1889. It was much bigger (16.5 mm diameter) than modern lenses (which measure around 8.4-9.6 mm). It also covered the sclera – unlike modern lenses that cover the cornea only. The first lenses were not only too large – they were also much too heavy and were falling out from the eye. Pain and significant discomfort caused by wearing lenses could have been mitigated with drops of cocaine.

Thomas Young (1773-1829) was first to discover the cause of astigmatism and the fact that the cornea doesn’t take part in accommodation. He also confirmed the possibility of removing the optical power of the cornea through contact with water. On Mechanisms of the Eye. Bakerian lecture delivered on the 27th of November 1800, published in 1801 Phil Trans. R Soc. 16 23-88. To prove it, he took out a small lens from a botanical microscope, covered the edge of its frame with wax and filled three quarters of it with water. Then he put his eye in the water so the cornea was half way between the lens and the edge of the frame. He discovered that the eye was unable to read: it became presbyopic. An application of an additional lens reverted it to the original – or even better – focus.