Vision History

The Braille Alphabet

Louis Simon Braille (1809 – 1852) was born in Coupvray, France, the fourth child and only son of Simon-René Braille, a saddle and horse tack maker, and his wife Monique.

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When Braille was three years old, he injured one of his eyes while playing with his father’s leather making tools. This resulted in both his eyes becoming infected, and by the time Braille was five, he was completely blind. Although there were few options for blind children his parents wanted Braille to be educated, first at the local village school then via a scholarship to attend the National Institute for Blind Youth in Paris.

This was the first school of its kind to educate blind students using a combination of oral instruction and raised-print books developed by the school’s founder. Braille did well at his studies and became an accomplished musician. And the crude raised-print books gave Braille the idea that a tactile alphabet would allow blind people to read and write.

In 1821, a retired soldier named Charles Barbier visited the school to share his invention called sonography. This was a complicated code used by soldiers to write and decode messages at night, using a system of twelve raised dots, without having to use a light. The army decided the system was too complicated, however Barbier thought the system might assist blind people.

Braille and some of the other students recognised the possibilities of sonography and over the next three years Braille worked to develop a much simpler system using six dots lined up in two columns of three dots each.

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Braille became an apprentice teacher at the school when he was 19 and in 1837 the school published the first book in braille. However, the school did not adopt the system. Nonetheless, by 1850, when tuberculosis forced Louis Braille to retire from teaching, his six-dot method was on its way to widespread acceptance.

Louis Braille died of his illness on January 6, 1852, in Paris, at the age of 43. Today, in most languages, braille is the standard form of communication used by blind people.

“Access to communication in the widest sense is access to knowledge, and that is vitally important for us if we are not to go on being despised or patronised by condescending sighted people. We do not need pity, nor do we need to be reminded that we are vulnerable. We must be treated as equals – and communication is the way we can bring this about.” Louis Braille 1841.

See the EZiD braille label here.

Albrecht von Graefe (1828 – 1870)

Friedrich Wilhelm Ernst Albrecht von Graefe  has become known as the father of modern ophthalmology.

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Albrecht’s father, Carl Ferdinand von Graefe, was a famous German surgeon and a general in the Prussian army. Young von Graefe became an orphan at age 12, however, as a gifted student, he was able to follow in his father’s footsteps by enrolling in medical school at the University of Berlin in 1843 when he was 15. He graduated four years later and then spent most of the next three years travelling across Europe studying and working with some of the leading ophthalmologists of that period.

His experiences allowed von Graefe to return to Berlin where he opened his first clinic in November, 1850. His talent underpinned the rapid growth of this clinic and in the first year he treated nearly 2,000 patients. He treated poor patients for free.

In the search for better ways to diagnose and treat his patients von Graefe designed new instruments including one of the first devices used to measure intraocular pressure. As his skills and knowledge grew he moved to larger clinic and was soon treating over 10,000 patients a year.

In January 1854, at the age of 26, von Graefe published the first issue of his ophthalmologic journal Archiv fur Ophthalmologie. Remarkably this journal is still published today under the title Graefe’s Archive for Clinical and Experimental Ophthalmology. Von Graefe went onto to contribute to other journals, and in 1857 he helped established the Deutsche Ophthalmologische Gesellschaft which was the world’s first ophthalmic society. Today the society sponsors the Graefe medal for achievements in the field of ophthalmology

Recognition of von Graefe’s achievements was also given by the hundreds of students who he trained. In 1857 von Graefe reached the peak of his career when he reported a cure for glaucoma using iridectomy which is a procedure to remove part of the iris.

In 1861 he became engaged to Anna, Countess Knuth. They married in 1862 and went on to have five children. Von Graefe also contracted acute tuberculous pleurisy in 1861. This did not slow him down and his work load continued to grow. Eventually the disease spread to his lungs and throat but he could continue to work by using morphine to control the pain. However, he eventually succumbed to the disease and died on July 20, 1870 at the age of 42, his wife died two years later at the age of 30.

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His image lives on in a statue that was erected by the Berlin Medical Society in 1882 in front of the Charité Hospital, and a Graefe Museum in the Heidelberg eye clinic.

by John Owens – john@ezidlabels.comwww.ezidlabels.com

 

Who Created The Eye Test Chart?

The eye test chart was designed by Herman Snellen (1834 – 1908) in 1862. Herman was a Dutch ophthalmologist and he developed the chart as an aid to measure an individual’s vision.

Snellen earned his medical degree at Utrecht University in the Netherlands in 1858. He specialised in ophthalmology after completing his degree and in 1877 was appointed a professor of ophthalmology at the University. His research was based on causes of low vision including glaucoma and astigmatism (a fault in the shape of the eye’s lens).

Other versions of eye test charts had been developed previously however these charts were never standardised. They used fonts of different sizes and shapes and did not necessarily provide an accurate assessment of a person’s real vision.

The British Army placed a large order for the Snellen chart in 1863, and from there it quickly became the global standard for almost 100 years. It is also the standard on which all more recent eye test chart systems are based.

Snellens’ innovation was to use specially designed characters, known as optotypes, instead of an existing, standard font. The Snellen optotype was based on a 5 x 5 grid and this grid was used to create a limited character set of 9 – 10 letters. The lines were a standard thickness and letters were all the same shape.

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This allowed the chart to be reproduced easily and provide accurate results wherever it was used.

The Snellen chart normally includes eleven lines of block letters. The first line comprises a single large letter, usually the letter E. Each of the following lines have increasing numbers of letters, each progressively smaller in size.

The Snellen eye test determines the visual acuity (clarity of vision) of an individual based on which is the smallest row of letters they can read.

With the traditional Snellen eye chart, the individual who can read the row of letters fourth from the bottom of the chart at 20 feet has 20/20 vision. The next three lines provide a measurement of 20/15, 20/10 and 20/5 vision. Not many individuals have 20/10 or better however many animals do, especially birds of prey, which may have an acuity of 20/5 or even better.

Testing with the Snellen eye chart helps reveal visual problems and symptoms of other medical conditions. However it is only one component of a complete eye examination.

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Images courtesy Wikipedia

by John Owens – john@ezidlabels.com   – www.ezidlabels.com