Aries Arditi, Ph.D, is the founder and Principal Scientist of Visibility Metrics, LLC. Visibility Metrics is a new venture for Dr. Arditi, who has devoted his career to a variety of research interests in human visual perception, spanning basic and applied studies in the human factors of vision and visibility and studies of functional visual impairment, including low vision and blindness.
Dr. Arditi spent most of his earlier research career at Lighthouse Guild International, with a brief two-year stint at the IBM Thomas J. Watson Research Center.
He is a former president of the International Society for Low Vision Research and Rehabilitation, a former editor-in-chief of the Informa Healthcare journal Visual Impairment Research, and has served two terms as a member on the National Eye Institute’s Low Vision and Blindness Rehabilitation Advisory Panel.
Dr. Arditi’s many and varied research interests include basic visual psychophysics; visual accessibility of the built environment, computers and Internet; text legibility; color and low vision; reading and low vision; assessment of vision function; wayfinding; binocular vision; functional perimetry, and prosthetic vision.
Among other notables, he is the developer of the Mars Contrast Sensitivity Tests, widely used throughout the world; and of LowBrowse, an open source add-on to the Mozilla Firefox browser for low vision. You can read more about Dr. Arditi’s scientific work and background at the Visibility Metrics website.
Maureen Duffy: Hello, Dr. Arditi. Thank you very much for taking the time to speak with us. Before we begin, can you clarify the correct pronunciation of your first name? You’re the only Aries (excluding the astrological sign) I know.
Aries Arditi: An easy way to remember how I and my family and friends pronounce my name is to note that it rhymes with “Paris.”
MD: As you know, I have always admired your work – but from afar! One of the first times I learned about your research interests was when I immersed myself in a study of the principles of color and contrast in the built environment and print legibility. I still refer to your publications and I use them every day in my own work. I also know how important it is to our readers who have low vision. Can you tell us more about your research in this area?
AA: The research in color contrast goes back a long time – I haven’t done much in this area lately, but I have to share credit with my collaborator Kenneth Knoblauch (now at INSERM, the French Institute of Health and Medical Research), who knows far more about color vision than I, and with whom I first developed these color guidelines.
I’ve always been interested in how to make things more accessible to those with low vision: make environmental features stand out more, make text more legible. While the work I’ve done in color contrast seems to have attracted more attention, I’ve actually devoted far more of my attention to text legibility. Making text more legible without making it bigger has big benefits both for designers of print publications AND for readers.
Keeping the amount of space text takes up on a page at a minimum keeps costs down for publishers, of course, so if you can make it more legible without increasing font size, for example, you can save money for them. There are similar benefits to readers with low vision too, though not necessarily financial ones. Low vision readers benefit because if they can read text with a little less magnification, they can see more of the “big picture” of the page (print or web) and can get away with zooming back and forth less, and with scrolling less.
Readers with moderate to severe low vision can also process more letters in a glance, and this can greatly improve reading efficiency. In the 1990s, I pioneered the use of parametrically defined fonts (i.e., fonts with characteristics that can be uniformly adjusted by changing the value of a variable, such as the width of a stroke, or the ratio of letter height to width) to study how specific variables affect text legibility in both able sight and low vision.
Since that time I’ve published many studies isolating the impact of font design characteristics like letter stroke width, spacing, proportionality, character aspect (width to height) ratio, presence or absence of serifs (those little ticks at the ends of strokes in some type faces), and letter case (upper- and lower case). All of these papers, by the way, are available on the Visibility Metrics website.
MD: I know you were – and are – very much involved in the development and evaluation of the Argus II Retinal Prosthesis System, which we follow very closely at VisionAware. How do you see it developing in the future?
AA: Actually, Maureen, you’re crediting me with more than I deserve here. The folks at Second Sight Medical Products are solely responsible for the development of the Argus II. I was merely a site Principal Investigator for the clinical trial of the Argus II that ultimately led to its approval for sale by the European Union and the United States Food and Drug Administration. Our site, at Lighthouse Guild, performed training on, and functional evaluation of, the device for the only New York area implant participant. It’s a very impressive technology in a rapidly evolving field.
MD: Can you tell us about the projects you’re working on right now?
AA: I’ve got several. First and foremost, Visibility Metrics was recently awarded a Phase I Small Business Innovation Research grant from the National Eye Institute to test the feasibility of a novel computer-vision based aid to help blind people orient themselves in their environments. That’s going to be taking up the bulk of my time in the coming year.
Second, I’m a co-Principal Investigator on a Department of Transportation-funded project to develop a robotic and computer-vision-assisted navigation aid for visually-impaired people. I’m working with great collaborators on that project: Drs. YingLi Tian (the Principal Investigator of the project) and Jizhong Xiao, from the Department of Electrical Engineering at City University of New York, and a very inspiring project leader at the Department of Transportation, Mohammed Yousef.
Third, I’m collaborating with Gordon Legge, from the University of Minnesota, on a new project to study visual imagery in people with low vision. This continues a thread in my research that started many years ago when I studied imagery in blind people with Harvard’s Stephen Kosslyn and Weill-Cornell’s Jeffrey Holtzman.
Fourth and finally, I’m gearing up to do some new accessibility studies on how to evaluate legibility and color discrimination in uncontrolled [i.e., out of the lab] environments.
MD: What do you regard as the next great frontier in vision science? I’m interested in your thoughts as a practicing vision scientist.
AA: There are so many frontiers that hold great promise right now that I’m hesitant to give any answer, but I’ll have to say that from what I’ve read, stem cell therapies for treatment of retinal diseases and optogenetics (techniques that allow stimulation of neurons that have been made light sensitive through genetic methods) studies of eye and brain are areas to watch closely over the next decade.
We thank Dr. Arditi for his support of VisionAware and for his research on behalf of blind and visually persons worldwide. You can read more about Dr. Arditi’s ongoing scientific work at the Visibility Metrics website.