June 5, 2006 4:00 AM PDT
Bringing vision to the nearly blind
Elizabeth Goldring is director of the Visual Experiences for the Blind Group at MIT's Center for Advanced Visual Studies (CAVS) and a nearly blind poet and artist. Due to a condition called proliferative retinopathy, Goldring sees only light and shadows.
"It comes and goes and mostly goes. I have no useful vision in my right eye. I use the machine on my left eye, which hovers around legally blind," Goldring told CNET News.com.
But using technology she helped create, she can see a Picasso line drawing, and read hundreds of words.
Goldring codeveloped a device called the Retinal Imaging Machine Vision System (RIMVS) over the last 15 years in collaboration with several scientists, doctors and MIT students. The machine allows those with vision as poor as 20/400--people who see only light and shadows in their everyday life--to read words, view color artwork and take virtual walk-throughs of architectural spaces.
The RIMVS works by projecting images directly onto a person's retina, using a light-emitting diode (LED) that passes through an LCD screen. Collimated light (light whose waves are parallel) focuses directly on the center of the pupil when a person puts an eye up to the projector. The entire system consists of the projector, a desktop computer, a monitor and a joystick.
"The beauty of the seeing machine is that you can load and place anything you can place on a regular computer desktop onto the machine. It's very simple. Someone without (vision loss) just needs to load it for the person with low vision," said Jackie McConnell, an undergraduate research student who works with Goldring.
The machine resembles a film projector, and to someone with 20/20 vision its images are recognizable but littered with graphical elements resembling the Benday dots of a Roy Lichtenstein "comics panel" painting. According to Goldring, a low-vision person sees the image without seeing this visual clutter.
While it is technically true that anything viewable on the average computer desktop also can be viewed via the RIMVS, Goldring says that most nearly blind people can see only simpler images. The bold rectangles of a Mondrian painting, for example, would be relatively easy for a low-vision person to see through the RIMVS. According to McConnell, it is still hard for low-vision individuals to see an entire Web page.
"Bad seeing is slow seeing, and you get too much visual info pretty fast and you can't cope if you can't see well," Goldring said, referring to her difficulty seeing complex images like Web pages via the RIMVS.
Goldring first was exposed to the idea of a "seeing machine" in 1985, when she was tested with a Scanning Laser Ophthalmoscope (SLO) machine by Dr. Robert H. Webb. Webb, the inventor of the SLO, is a senior scientist at the Schepens Eye Research Institute at Harvard University, and continues to collaborate with Goldring. He was using the SLO at the time to conduct diagnostic tests on Goldring's retina, after hemorrhaging had left her essentially blind. Goldring was able to read the word turtle. She then asked Webb to write the word sun and was able to see that, too, much to her joy.
"I do have visual experience. I have the persistence of visual memory. You lose visual memory, or it begins to erode. I was without it long enough that I realized (at one point), 'my visual memory has been eroded.' The (SLO) machine did stimulate my visual thinking," Goldring said.
Since her first exposure to the SLO, Goldring has continued using retinal projection as a gateway to visual experience. In doing so, she has developed an English-language dictionary of visual words for the legally blind.
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