Just my Optotype

By Emily Miranker, Events & Projects Manager

You’ve probably seen the star of today’s post. Or, rather, peered at it trying to see it clearly (like yours truly). That pyramid of big letters with subsequent lines of more letters getting smaller and smaller: the eye chart.

Snellen Chart_weiss & Sons Catalogue_1898_watermark

The relationship of the distance at which the test is done and the distance as which the smallest figure is (correctly) identifiable defines the patient’s visual acuity. Source: John Weiss & Son (1898).

The German physician Heinrich Kuchler created the first eye chart in 1836 with cuttings from books, papers, and almanacs that he glued to a sheet in ever decreasing size.

Kuchler eye chart_1836_cropped

Kuchler eye chart. Source: SchoolHealth.com

While Kuchler’s example above is not as cleanly designed as this post’s first image, it was a definite improvement over times past. People basically had to self-diagnose themselves or read a piece of text with a doctor and pick the (hopefully) correct lenses. By the nineteenth century, the need for individualized lenses was clear. In 1862 Dr. Franciscus Donders asked his colleague (and eventual successor to the directorship of the Netherlands Hospital for Eye Patients), ophthalmologist Herman Snellen to design a chart.[1] Now called the Snellen chart, it has become one of the most common.

According to Smith-Ketterwell Eye Research Institute scientist and an eye chart design expert, Dr. August Colenbrander, Snellen experimented with dingbats, shapes and even lines of text for the eye chart.[2] But patients could assume the ending of phrases based on context, and symbols were hard to describe. So Snellen stuck to letter forms –but do they look a little odd to you?

Snellen and E Charts_Reynders & Co Surgical Instruments_1889_watermark

To the right of the above Snellen Chart is an E Chart, sometimes called a Tumbling E Chart, which works along the same principles but is used for those who cannot read, like children, or patients unfamiliar with the Latin alphabet. Source: Reynders, John, & Co. (1889)

If your answer is yes, you’re picking up on the fact that Snellen developed a specific kind of letterform called an optotype. Once he concluded that letters were better for vision, he speculated that subjects would identify equally weighted letters of consistent size more easily. So he created a complete typeface in a grid system.

Optotype 5x5 grid

Optotype on 5×5 grid. Source: http://abcdefridays.blogspot.com

Typical typefaces have different line thicknesses and ornamental touches (like the dot on lowercase i’s, the cross-stroke of T’s).  Letter proportionality is usually determined by family groupings (like h, m, n, r, and u). Snellen developed a 5 x 5 grid for his optotypes so the width and height of an optotype is five times the thickness of the line weight.[3] Snellen based his grid on a medical measurement, the arcminute, or one sixtieth of a degree.[4] In optotypes, the weight of a line is equal to the negative space between lines. Typically, C and D would appear wider than Z. The opposite is true of optotypes.

Snellen isn’t the only game in eye chart town. Others include the Jaeger chart, Landolt C, LEA test, LogMAR charts and the Golovin-Sivtsev table. Retired eye surgeon and antique eye glasses expert David Fleishman attributes the Snellen’s widespread popularity even after the advent of other vision assessments to it’s being a “low-tech solution to a complex problem because it was cheap and easy to use.”[5] The 21st century is making its own easy to use -if high-tech solutions– such as the newly released Warby Parker Prescription Check app which utilizes a user’s laptop and iphone to check their vision. The app allows an eye doctor to assess your prescription; though the app stresses it does not replace a comprehensive eye exam.

Warby Parker app

Warby Parker website.

Whatever computer screens hold for the future of vision checks, the Snellen remains one of the top selling posters in the United States.[6]

Special thanks to Avery Trufelman and the 99 Percent Invisible podcast team for inspiration from Episode 242: Mini-Stories: Volume 2.

References:
[1] Kennedy, Pagan. “Who Made that Eye Chart?” The New York Times. New York: May 14, 2013.
[2] Frear, Lori. “What are Optotypes? Eye Charts in Focus,” I Love Typography: July 12, 2015. Accessed 8/1/17.
[3] Frear, Lori. “Examining the Fascinating Typographic History of Eye Charts.” Gizmodo: September 24, 2015. Accessed 8/2/17.
[4] Kalatschinow, Alex. “Optotype: Typography of the Eye Chart,” ABCDEFridays: A Typographic Inspiration Blog: Tyler School of Art of Temple University. Accessed 8/2/17.
[5] Kennedy.
[6] Bordsen, John. “Eye Chart Still the Standard for Vision.” Seattle Times. Seattle: August 9, 1995.
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Good eyes are your protection

By Rebecca Pou, Project Archivist

goodeyesareyourprotection“Wear glasses if the doctor advises you to do so.” “Don’t rub your eyes with dirty hands.” “If you suspect eye trouble, see an oculist at once.” This sound advice comes from a 1917 trifold leaflet aimed at school children and published by the Illinois Society for the Prevention of Blindness (ISPB), which was founded in 1916.

breadwinnersWhile the pamphlet contains helpful recommendations on eye health, the illustrations and design are particularly charming. Eyes peer out from the sign on the front cover, but we discover that those eyes belong to a boy in spectacles on the page beneath and the sign has cut outs. The eye holes must have been irresistible to children and are surrounded by guidelines for healthy eyes.

healthwealthhappiness

Click to enlarge.

The pamphlet stresses that proper eye care beginning in childhood confers life-long benefits, especially in a cartoon comparing two couples from an eye screening in childhood through old age. The pair that cares for their eyes flourishes in life, excelling in academics, extracurricular activities, and, in the case of the man, his profession. The other couple is plagued with nervousness and headaches, and both have trouble with work. While the pamphlet is aimed at children, the lesson is for parents as well. In her old age, the content woman is grateful to her mother for getting her the eye care she needed, while the unfortunate pair’s parents had dismissed the eye examiners’ recommendations.

goodcareorneglect

Click to enlarge.

And for anyone who might need further convincing, the Society contrasts good sight and bad sight in black and white.

goodsightpoorsight

In his landmark book, The Evolution and Significance of the Modern Public Health Campaign, published in 1923, C-E. A. Winslow asserts that education and changed behavior are central to modern public health efforts.  He says, “the fight must be won, not by the construction of public works, but by the conduct of the individual life.” In this pamphlet, the ISPB is clearly appealing to individuals, encouraging them to choose good care over neglect, preventing the difficulties in life caused by blindness and eye disease.

Almost a century after the publication of “Good eyes are your protection,” the ISPB still exists and maintains a website. While their efforts seem more expansive, consisting of education, research and programs, the organization remains “dedicated to the care, protection, and preservation of sight.”