Help build a timeline of visual corrective technologies and innovations to aid blind persons

“Making Matrix for magazine for blind.” Photograph from glass negative, between ca. 1900 and ca. 1915. Image depicts a man at the New York Institute for the Blind using a Stereograph, a machine for embossing zinc plates with Braille, to use as publishing masters. George Grantham Bain Collection, Library of Congress, Prints and Photographs Division, Washington, D.C., USA.

For the upcoming GLIMPSE journal issue on the topic of Blindness, GLIMPSE correspondent Nadej Giroux has drafted a fascinating timeline of corrective technologies and innovations to address blindness.

We welcome your feedback and ideas (supported by citations, please!) on this draft.

The final version will be published in GLIMPSE issue #10, with a full bibliography and attribution to those who contribute!

Selected Dates in Vision:
Corrective Technologies and Innovations

ca.1286 — First glasses are created in Italy by the Dominican friar, Giordano da Pisa.

1508 – Leonardo da Vinci is first to introduce the concept of “contact lens” in his Codex of the eye, Manual D. Though none are produced at the time, the concept explored the idea of directly increasing corneal power of the eye.

1784 – Benjamin Franklin writes a letter to George Whatley, which describes his recent invention of “split double spectacles,” or bifocal lens glasses.

1786 – Valentin Haüy publishes a book titled An Essay on the Education of the Blind, in which he describes a process wherein the typographical characters used on a printing press would emboss letters upon the wet paper medium, thus creating a tactile font.

1823 – Creation of the first Fresnel lens, as attributed to Augustin-Jean Fresnel. Fresnel lenses are different from the regular spherical lens of a standard magnifying glass in that the former can be much thinner due to its structure, which is comprised of a set of thin raised concentric sections. As sight aids, Fresnel lens technology has been used to create flat magnification sheets that can be placed over a TV screen, helping to magnify the image.

1829 – Louis Braille publishes a book titled Method of Writing Words, Music and Plainsong by Means of Dots for Use by the Blind and Arranged for Them, exhibiting and explaining the original Braille type in French that is based on dots. More that half a century later, Braille type is introduced in Britain.

1837 – August Seebeck, classifies two distinct types of color blindness and is first suggest that the condition can be augmented with corrective lenses.

1851 – Hermann von Helmholtz invents the first ophthalmoscope, calling it an “eye mirror,” which is used to illuminate the interior of the eye behind the pupil.

1888 – Adolf Gaston Eugen Fick produces and fits the first successful pair of contact lenses. They are made of heavy blown glass with a dextrose solution inside. Although the original Fick lenses were a breakthrough, they were rather bulky and could only be worn for several hours at a time.

1905 – Eduard Zirm performs the first successful corneal graft surgery, by transplanting corneal tissue and partially restoring sight to a blind man named Alois Glogar.

1949 – Sir Harold Ridley performs the first-ever successful implantation of intraocular lens, a procedure that many contemporary ophthalmologists considered impossible at the time.

1980s – Scanning Laser Opthalmoscope is developed to view microscopic layers of the retina of the living eye, and aids in diagnosing retinal disorders.

1999 – Professor Ingo Potrykus invents Golden Rice. This genetically engineered varietal was designed to contain beta carotene, which, when consumed is converted to vitamin A in the human body. Since vitamin A deficiency is linked to blindness, especially in the developing countries, the Golden Rice, along with Orange-fleshed sweet potato, are examples of biofortification tools that aim to prevent vision problems linked to VAD in the future.

2001 – ChromaGen lens human subjects study is published in Ophthalmic and Physiological Optics. The study used the ChromaGen brand color blindness corrective lenses in a two-week experiment that yielded positive subjective results in its wearers, among which were the significant reduction of Ishihara error rates, the later being the most common color blind test of circles and dots of varying sizes and with numbers represented in contrasting colors.

2002 – Argus Retinal Prosthesis is developed by Second Sight TM. This bionic eye project created a product that is a retinal prosthetic system, which induces visual acuity of blind patients by means of electrical stimulation to the retina, bypassing the damaged photoreceptors. With an aid of compact camera and video processing unit (VPU), the device “sends” the scene captured via camera though a cable to the VPU, to reconstruct the visual information for the Argus-II wearer. In September 2012, FDA recommended the approval of the second-generation Argus-II device, following several successful clinical trials in Europe, Mexico and United States.

2005 – Elizabeth Goldring, artist, poet, and head of the Vision Group at the Center for Advanced Visual Studies at the Massachusetts Institute of Technology, leads a team of engineers and physicians in the development and first clinical trials of the Seeing Machine Camera (SMC). The device uses liquid crystal display (LCD) and light-emitting diode (LED) technologies to affordably and portably replicate principles of the industrial-grade Scanning Laser Opthalmoscope. The SMC projects imagery directly onto the retina with highly-focused, bright light, avoiding the normal distortions and refractions of the impaired eye. The SMC allows people with a visual acuity of 20/70 or less to see things they would otherwise be unable to see (including small details of facial features), and to produce photographs of what they see.

2009 – Gene therapy is shown to successfully cure color blindness in two squirrel monkeys. The therapy worked by increasing the red end of the spectrum sensitivity of cone cells, effectively restoring color vision in the study’s subjects. The results of the study suggest further implication for treating human color blindness in the future.

2010 – First success with biosynthetic cornea transplantation procedures is reported by Fagerholm et al. of Linkoping University in Sweden. The development of the biosynthetic corneas rose out of shortage of donated corneas readily available for transplantation. The corneas in the Fagerholm’s lab were produced by injecting the human gene, responsible for collagen production into a type of yeast cells that were later molded into the corneal shape.

2012 – Prosthetics + Mouse retina code

2013 – Implantable telescope for age-related macular degeneration

Galileo’s illusion solved by New York vision researchers

Portrait of Galileo Galilei, 1605-1607, by Domenico Tintoretto. Image courtesy of Wikimedia Foundation.

It was 1632, and the father of modern astronomy was perplexed as to why Venus, when observed by “naked” eye, would appear substantially larger than Jupiter, which was actually four times larger than Venus. He knew that Venus’ exaggerated size must have something to do with it’s halo, or “radiant crown” as he described it, and that this halo must have something to do with his eyes, and not the celestial objects themselves. Observations via telescope presented a more accurate visual representation of the mathematically-verifiable proportions of the planets.

Almost 400 years later, Neuroscientists Susana Martinez-Conde and Stephen L. Macknik, eloquently explain the January 2014 published findings of the State University of New York’s vision researchers Jens Kremkow, Jose Manuel Alonso and Qasim Zaidi:

By examining the responses of neurons in the visual system of the brain—to both light stimuli and dark stimuli—the neuroscientists discovered that, whereas dark stimuli result in a faithful neural response that accurately represents their size, light stimuli on the contrary result in non-linear and exaggerated responses that make the stimulus look larger. So white spots on a black background look bigger than same-sized black spots on white background, and Galileo’s glowing moons are not really as big as they might appear to the unaided eye.

These now-isolated differences in how our photoreceptors operate also explain why it is easier to read black text on a white page, than to read white text on a black page, a topic of interest to our typographer and font designer friends.

Do you love Galileo as much as we do? Check out the GLIMPSE Cosmos issue, available in our archives.

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GLIMPSE journal is an interdisciplinary supercollider of works that examine the functions, processes, and effects of vision and its implications for being, knowing, and constructing our world(s). Each theme-focused issue features articles, visual essays, interviews, and reviews spanning the physical sciences, social sciences, arts and humanities. GLIMPSE contributors are leading and emerging scholars, researchers, scientists and artists from around the world. Some of our contributors are independent thinkers and doers with no formal institutional affiliations, and others are affiliated with the most respected research institutions in the world. Read all about them.

Eat Your Carrots! The Chemistry of Vision

 

“Sandwich Carrots-Dainty Sandwich Carrots.” Hand-colored etching. Gillray, James, 1756-1815, engraver. Published by H. Humphrey, 1796 Dec 3d, London.
Image courtesy of Library of Congress.

You’ve probably heard the old adage about eating carrots for good vision. Well, there is some truth to it. Carrots contain a high concentration of β-carotene which gets broken down in the intestines to form the aldehyde (hydrocarbon) form of vitamin A, cis-retinal. Vision deteriorates in the absence of vitamin A because cis-retinal is trafficked along the protein, opsin, to produce electrochemical signals from light.

Our retinas perceive light in tiny particles called photons. As soon as these photons hit the retina, they isomerize cis-retinal to trans-retinal.  Trans-retinal then bonds to opsin to form rhodopsin. Rhodopsin is a purple pigment in the photoreceptor cells of the retina that reads blue-green light. This is the first step of the phototransduction cycle where photon energy is transferred to a series of signaling and diffusing protein complexes.

Retinal isomerism drawn with ChemDraw

Mutated forms of rhodopsin will be folded and transported differently and could lead to deteriorated vision or blindness. In more rare cases, mutations can cause rhodopsin to be constantly activated, even in the absence of light. Hypersensitivity, autoimmune disorders, and mutations can all cause rod cells in the retina to undergo apoptosis or cellular self-destruction. This sort of degradation of the retina will ultimately lead to deteriorated vision and eventually blindness.

The absorbance of cis-retinal is optimized at approximately 100 nanometers less than rhodopsin and it is a very rigid molecule because of the arrangement of its double bonds. Thanks to isomerism, we can see in color as opposed to ultraviolet! As all of the above demonstrates, our ability to see involves a series of complicated and precisely regulated bio-chemical processes, and carrots play their role.

We will be exploring more about vision loss and blindness in the upcoming GLIMPSE issue 10, Blindness. In the meantime, let us know your thoughts, research, questions, or experiences related to the topic.

If you’re interested in the chemistry of vision and why we perceive the section of the electromagnetic spectrum that we do, you might also be interested in GLIMPSE, issue 4, Color, and the article on “Human Potential for Tetrachromacy” by Kimberley A. Jameson and the online supplementary article.

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Myya McGregory is the GLIMPSE 2012 Science Writing Intern. She is a junior double-majoring in chemistry and economics at Williams College. She enjoys music, dance, and literature.

Persistence of Vision

As  many of you will soon find out in the upcoming Cinema issue, persistence of vision is «the phenomenon of the eye by which an afterimage is thought to persist for approximately one twenty-fifth of a second on the retina». While the image is burned on the retina of the eye, we have time to send signals to the brain to identify the image.

Still from a flipbook created at the Museum of the Moving Image. Credit: Julia Rubinic

Persistence of vision, though thought to be a myth, could explain why our eyes perceive one continuous, moving image when we look at a progressions of stills.

This theory not only explains flipbooks but is also the basis of many film devices of the 19th century. The idea that images remain on the retina seconds after viewing means that images can be perceived as moving at speeds as low as 5 frames per second.

This  also means that if an image vibrates fast enough, it can be perceived as static rather than kinetic.

Check out this website by the American Museum of the Moving Image to discover more.

Ophthalmic Photography

These opthalmic photographs are definitely worth a gander… Thanks to “Eyeballs by Day, Crafts by Night” for sharing their work!

I get a lot of questions about what exactly I do, and a lot of confused looks when I introduce myself as an ophthalmic photographer.  I work in a unique and interesting field photographing the insides of people’s eyes, specifically the retina. The retina lines the back wall of the eye and is responsible for our detailed vision.  My imaging of the retina provides the  doctors with crucial information that allows them to diagnose and treat retinal … Read More

via Eyeballs By Day, Crafts By Night

Refractions, Retroscopy, and Sherlock Holmes

Sir Arthur Conan Doyle. Courtesy of the Library of Congress.

We at Glimpse tend to see people as multi-faceted, which of course they are. Rarely are experts in any given field motivated by one singular vision. This holds true for the great mystery writer, Sir Arthur Conan Doyle. Although he is perhaps most famous for his grisly Sherlock Holmes series, Doyle was also a practicing ophthalmologist, at least for a little while.

Doyle attended medical school at the University of Edinburgh from 1876 to 1881 where he was deeply impressed by one of his teachers in particular, Joseph Bell. Bell held keen powers of observation and deduction, and could often diagnose a patient simply by studying the condition of his or her fingernails! In fact, it was in Bell that Doyle found his prototype for the meticulous detective work of Sherlock Holmes (Doyle gave Sherlock the last name of “Holmes” in reverence for Dr. Oliver Wendell Holmes).

Doyle himself went on to experience a somewhat fragmented career in medicine, spending part of his post-graduate years as a ship surgeon on the west coast of Africa, and eight and a half years as a practicing physician in Southsea. Finding little financial success, Doyle pursued ophthalmology in London. In The Stark Munroe Letters, Doyle’s autobiographical character Stark explains,

“I’ve taken to the eye, my boy. There’s a fortune in the eye. A man grudges a half-crown to cure his chest or his throat, but he’d spend his last dollar over his eye. There’s money in ears, but the eye is a gold mine!”

The eye did not prove to be the financial gold mine Doyle had hoped for, but it did serve as inspiration for certain Sherlock Holmes stories such as “The Adventure of the Golden Prince-Nez.” In the story, Holmes detects the “sex, facial appearance, body structure, and walk of the suspect” from a mere pair of glasses.

Doyle’s contributions to medicine may have been scarce, but his love affair with the field proved invaluable to readers. As a doctor by the name of Maurice B. Campbell noted in the British Medical Journal in 1934,

“It is doubtful if the works of any other novelist describe extrasystoles, oedema due to fibrillation, angina pectoris, aneurysm, rheumatic valve disease, and left ventricular failure with orthopnea with such careful adherence to medical probabilities.”