The problem of applying advanced electronic imaging and computer display technologies to aid persons with visual disabilities has resulted in bulky and obtrusive eyewear that has been shown in the marketplace not to be worth the high price. Nonetheless, with US citizens both living and staying active longer, there is even greater need for effective, wearable, and desirable low vision aids. There are 14 million Americans that are hampered in their daily lives by partial loss of visual acuity and/or insufficient visual field (National Advisory Eye Council 1998), and that number is expected to rise much faster than the rate of population growth. A new approach is being undertaken in this study, hinging upon a new display technology, called retinal light scanning. By scanning a low power beam of light from a laser or light-emitting diode directly into the eye, a bright image is generated as the beam is modulated in power and scanned across the retina. This 'laser light show on the retina' provides not only brighter display illumination than standard displays, but the narrow beam provides unprecedented depth of focus. Reading speed studies conducted in our laboratory have shown that retinal light scanning has great potential for transferring images to the retina with minimal distortion. In concert with the recent development of retinal light scanning, technological improvements have been made in micro-cameras, wearable computers, real-time image processing, and spectacle-mounted hardware. Our approach is to reduce the size and cost associated with retinal light scanning which will be redesigned specifically as a wearable low vision aid. We will incorporate the latest advancements by our collaborators in the areas of cameras, wearable computers, and image processing. These technologies will be integrated into prototype vision aids that will be a testbed for our newest theories of human-computer interface science, such as spectacles that have an augmented central view from retinal light scanning while allowing natural viewing of the surroundings to maintain situational awareness. In collaboration with the Department of Services for the Blind in Seattle, WA and the Schepens Eye Research Institute in Boston, MA, we will test the prototype low vision aids and their performance in the hands of low vision volunteers doing everyday tasks. Thus, we believe the same problems that have led to a lack of acceptance of previous high-tech vision aids can be overcome by using retinal light scanning technology as a basis for our research effort. From our experience, the goals of designing and testing novel vision aids for the partially sighted in our community is highly motivating and rewarding work for both undergraduate and graduate science and engineering students.
