The Optacon (OPtical to TActile CONverter)L.H. Goldish and H.E. Taylor, "The Optacon: A Valuable Device for Blind Persons", NEW OUTLOOK FOR THE BLIND, published by the American Foundation for the Blind, Feb. 1974, pp. 49-56 is an electromechanical device that enables blind people to read printed material that has not been transcribed into Braille. The device consists of two parts: a scanner which the user runs over the material to be read, and a finger pad which translates the words into vibrations felt on the finger tips. The Optacon was conceived by John Linvill, a professor of Electrical Engineering at Stanford University, and developed with researchers at Stanford Research Institute (now SRI International). Telesensory Systems manufactured the device from 1971 until it was discontinued in 1996. Although effective once mastered, it was expensive and took many hours of training to reach competency. In 2005, TSI suddenly shut down. Employees were "walked out" of the building and lost accrued vacation time, medical insurance, and all benefits. Customers could not buy new machines or get existing machines fixed. Some work was done by other companies but no device with the versatility of the Optacon had been developed as of 2007. Many blind people continue to use their Optacons to this day. The Optacon offers capabilities that no other device offers including the ability to see a printed page or computer screen as it truly appears including drawings, typefaces, and specialized text layouts.
Description
The Optacon consists of a main electronics unit about the size of a portable tape recorder connected by a thin cable to a camera module about the size of a penknife (See Fig. 1).
The main electronics unit contains a "tactile array" onto which the blind person places their index finger. The Optacon user moves the camera module across a line of print, and an image of an area about the size of a letterspace is transmitted via the connecting cable to the main electronics unit. The tactile array in the main electronics unit contains a 24-by-6 matrix of tiny metal rods, each of which can be independently vibrated by a piezoelectric reed connected to it. Rods are vibrated that correspond to black parts of the image, thus forming a tactile image of the letter being viewed by the camera module. As the user moves the lens module along the print line, tactile images of print letters are felt moving across the array of rods under the user's finger. The Optacon includes a knob to adjust the intensity at which the tactile array rods vibrate, a knob to set the image threshold between white and black needed to turn on the vibration of the rods in the tactile array, and a switch that determines whether images will be interpreted as dark print on a light background or as light print on a dark background.
Lyle Thume, an Optacon user and director of blind rehabilitation services at the Rehabilitation Institute in Detroit summed up the Optacon this way in 1973: "It opens up a whole new world to blind people. They aren't restricted anymore to reading material set in braille."
History
The Optacon was developed by John Linvill, a professor of Electrical Engineering at Stanford University, who later became head of the Electrical Engineering Department. The Optacon was developed with researchers at Stanford Research Institute (now SRI International). Linvill was one of Telesensory's founders and Chairman of the Telesensory Board. The initial stimulus for development of the Optacon was Linvill's daughter, Candy (born 1952, blind since the age of 3). Using the Optacon, Candy graduated from Stanford and received a PhD. She has worked as a clinical psychologist since, so, like her father, she is often referred to in the press as "Dr. Linvill".
In 1962, during a sabbatical year in Switzerland, Linvill visited an IBM laboratory in Germany, where he observed a high speed printer that used a set of small pins—like hammers—to print letters onto strips of paper. He thought, "If you could feel the hammers with your fingertip, you could surely recognize the image." So on our return to Zurich, I told my wife and son and daughter, Candy, who was blind: "Guys, I've got the most magnificent idea. We'll make something that will let Candy read ordinary printed material." And although his family laughed at this notion, "oh, that'll never work!" the idea for the Optacon was born.
Upon returning to Stanford, Linvill, together with graduate students G.J. Alonzo and John Hill, developed the concept further with the support of the Office of Naval Research. A key aspect of Linvill's concept was to use vibrating piezoelectric reeds, called bimorphs, to move the pins in a two-dimensional array to produce tactile images.J.G. Linvill and J.C. Bliss, "A Direct Translation Reading Aid for the Blind", Proceedings of the IEEE, Vol. 54, No. 1, Jan. 1966, pp. 40-51 The idea of using vibrating bimorphs was critical for several reasons: The high power efficiency of the piezoelectric bimorphs made a battery-powered reading machine possible. The small size and weight of the bimorphs was also essential for portability. Later psychophysical experiments discovered that vibration around the resonance of conveniently sized bimorphs was optimum for the sense of touch.
In 1964 Linvill applied for a patent, and U.S. Patent 3,229,387 was granted in January 1966.
Early history
Amazingly, in 1913 a reading machine for the blind, called the optophone, was built by Edmund Edward Fournier d’Albe in England. It used selenium photosensors to detect black print and convert it into an audible output which could be interpreted by a blind person. A small number were built with reading being exceedingly slow for most people. The concept of a tactile optical scanning device can be traced back to 1915, as mentioned (and dismissed) in Fournier d'Albe's 1924 book, The Moon-Element.E.E. Fournier d'Albe, "The Moon Element", published by D.Appleton and Company,1924, pp. 112-113 - https://archive.org/details/moonelement002067mbp/page/n127 Described as a device using iron pins stimulated by electro-magnets to convey dark and light in a tactile manner, questions hung over the feasibility of such a device, and indeed, if it existed at all at that time.
Of note, in In 1943, Vannevar Bush and Caryl Haskins of the wartime Office of Scientific Research and Development directed resources toward the development of technologies to assist wounded veterans. The Battelle Institute was provided with funding to develop an improved Optophone and Haskins Laboratories was funded to conduct research toward a synthetic speech reading machine. This group turned “sour” on the Optophone approach after concluding that reading would be too slow.
In 1957 U.S. Veteran's Administration, Prosthetic and Sensory Aids Service (PSAS), under Dr. Eugene Murphy, began funding the development of a reading machine for the blind. The principal investigator on this project was Hans Mauch, a German scientist brought to the U.S. after World War II. (During World War II Mauch worked for the German Air Ministry as part of the German V-1 missile development team.)
Mauch worked on reading machines having an “optophone-like” output, a “speech-like” sound output, and a synthetic speech output. The only one of these that was competitive to the Optacon development was the Stereotoner, basically an improved optophone. The Stereotoner design concept was that the user would move a vertical array of photosensors across a line of text. Each photosensor would send its signal to an audio oscillator set to a different frequency, with the top photosensor driving the highest frequency and the bottom photosensor driving the lowest frequency. The user would then hear tones and chords from which the letters could be identified.
Initially Linvill was unaware that the Optacon was not the only reading machine for blind people under development. However, in 1961 James Bliss had returned to SRI from MIT where he had done a doctoral dissertation in a group working on the application of technology for the problems of blindness. Bliss was interested in basic research on the tactile sense, to better understand how it could be used to substitute for loss of vision. While at MIT, Bliss became aware of the existing research and development on reading machines for the blind, as well as the researchers and funding agencies. At SRI Bliss had obtained funding for his tactile research from the Department of Defense and NASA, who were interested in tactile displays for pilots and astronauts. This had enabled him to obtain a small computer and develop software to drive hundreds of tactile stimulators he had developed for research purposes. These tactile stimulators were small air jets, which were ideal for research because their arrangement and spacing could easily be changed and the contact to the skin was always assured. Bliss was studying how well subjects could recognize dynamic patterns presented on his array of air jet stimulators.
Funding for Optacon research and development
After Linvill and Bliss decided to join forces to work on Linvill's vision of a reading machine, it became apparent that they needed to obtain funding for this objective, rather than the objectives of Department of Defense and NASA which had provided the funding up until that time. As a start, Bliss suggested that they visit Dr. Murphy at the VA, since he was the only then currently active government source of reading machine funding. However, Bliss knew that the research on “Optophone-like” reading machines had created negativity toward this “direct translation” approach because of the slow reading rates obtained. To counter this negativity, Bliss programmed an SRI computer to present text in a moving belt display, similar to that in Times Square New York City, on both his air jet stimulator array and on the Stanford bimorph array. Linvill's blind daughter, Candy, was then the subject who attempted to learn to read the text presented in this fashion. After several hours of training and practice, Candy was reading in excess of 30 words per minute. Bliss and Linvill felt this computer driven test was a valid simulation of the reading machine they proposed to develop. They felt the 30 words per minute reading rate achieved in a short time by Candy proved that if such a reading machine were developed, it would be useful. They didn't know what the upper limit of reading speed would be, but had hopes that 100 words per minute could be achieved, since this was typical Braille reading rate.
Armed with this result, Bliss and Linvill made an appointment to visit Dr. Murphy in Washington, D.C. Initially the meeting was going very well, with Dr. Murphy seeming to be very positive toward the possibility of funding the development. Murphy then mentioned that Linvill would have to assign his patent to the Veterans Administration. Linvill refused and the meeting abruptly ended.
As it turned out, this rejection was fortunate. The Office of Education was directed by a colleague of Linvill's from when he worked at Bell Laboratories. Development of a reading aid for the blind was very relevant to their mission since providing instructional material to blind mainstreamed students was an important problem. Linvill presented the Optacon idea to the Office of Education and it was enthusiastically received. This led to funding at a higher level (over $1.8 million of 1970 dollars over 4 years) than would have been likely from the Veterans Administration.
This higher level of funding was necessary to develop the custom integrated circuits that enabled the Optacon's small size, which was critical to its success. The Optacon project also assisted Stanford in establishing their Integrated Circuits facilities, leading MIT's Dean of Engineering to remark that Stanford got the lead in integrated circuit research because of the Optacon.
Development of the Optacon