you for inquiring about the potential application of the Virtual Retinal
Display as an assistive device for people with low vision. Many people
with low vision, their family members, and friends are looking for assistive
devices and techniques to enable improved performance of daily visual tasks
at home, at work, and in the community. We believe that the technology
of our Virtual Retinal Display can provide an important new tool for people
with low vision. At this point the technology is in prototype stages. With
further refinements and miniaturization we are working toward making this
technology available as personal use products by people with low vision.
We are working with our corporate partner to make products commercially
available to the public soon.
The Virtual Retinal Display
VRD, as we call it, is a completely new way of creating images upon the
retina of the human eye. The VRD was invented and patented here at the
Human Interface Technology Laboratory (HIT Lab) on the campus of the University
of Washington by Dr. Thomas A. Furness III, the director of the laboratory.
Dr. Furness was recently honored as the recipient of the 1998 DISCOVER
Magazine Award for Technological Innovation in the SIGHT category. Perhaps
your interest in the VRD came from publicity resulting from this award.
Instead of using the eye to focus on a video screen or a computer screen,
our new VRD scanner technologies converts these electronic messages and
"paints" images such as pictures and print directly onto the retina. We
believe that the VRD will be a useful low vision aid for people who have
a broad variety of eye conditions that cannot be improved via standard
eye care procedures or by many currently available low vision aids.
How the VRD Works
VRD uses a very narrow beam of scanned light to enter the eye. If the optics
of one's eye are impaired or otherwise create distortions, we can pass
VRD laser beams through many of these problem areas and onto the retina.
To illustrate, eyeglass wearers with low vision who have tried the VRD
report seeing the exact same quality of image both without their eyeglasses
and when viewing through any portion of the lenses of their glasses, including
any bifocal or trifocal lenses. Once the narrow VRD beam has passed through
one's glasses and the iris of one's eye, the scanning feature of the VRD
causes the beam to widen on its path to the retina. When the image reaches
the retina it is about 30 degrees wide. While this is more than sufficiently
wide for reading, we are working ways to increase this width for some applications.
If the retina of one's eye is impaired, we can use the VRD to provide an
image that is much sharper and can be controlled to be much brighter than
other displays. Since the VRD does depend upon the reception of an image
by the retina and a functioning optical nerve pathway in the brain, the
VRD will not work for people who have complete loss of retinal or optic
Who Can Benefit from the VRD
to the Washington State Department of Services for the Blind, about 93,000
people in Washington State and 4.4 million people the United States currently
have useable vision that is amenable to improved visual functioning via
appropriate low vision aids and techniques. By the year 2020, this number
will swell to about 159,000 in Washington State and 7.6 million people
in the United States. We are confident that the VRD has the potential of
being a significant low vision aid for a wide range and large number of
Future Developments with the VRD
present status of our research in the application of the VRD for low vision
is exciting, but preliminary. Our current laboratory versions of the VRD
are bulky and must be operated by our engineers. We have tested the VRD
with a large number of people with a variety of visual disorders. We have
promising data that shows the VRD can be a significant low vision aid for
many people, yet we need to learn more about the applicability for several
other kinds and degrees of low vision. Our primary job right now is to
secure additional funding from business or government agencies to help
us do more tests and design improved VRD devices with perhaps individualized
applications for people with of low vision. We have been very fortunate
and have some funding from the National Science Foundation, a Federal government
research agency, to help us in our initial development work.
partner of the Human Interface Technology Laboratory is a Seattle firm
called Microvision. Microvision
is hard at work developing VRD products for medical and military applications
as well as high quality, inexpensive, and compact versions of the VRD.
We hope these versions will be adapted for use by people with low vision
and made available as products to the public soon. We are working with
Microvision toward this end.
know that people with low vision are anxious to use technological breakthrough
devices and we are doing our best to assure that future versions of the
VRD will be available for users soon. We ask for your patience as we carry
out our research with low vision subjects from state and local agencies.
Information about future VRD studies for low vision persons in the Seattle
metro area will be accessible on this web site. We are sorry that
we cannot begin to fulfill the many requests we have by individuals with
low vision to try the VRD. Our progress will be posted on our web
site that can be accessed on the Internet at www.hitl.washington.edu.
If you have ideas for helping our research efforts, either with funding
or technology, please email us at the links below or send us a letter at
Interface Technology Laboratory
University of Washington
Seattle, WA 98195-2142