Vision Aid
From: NASA Tech Briefs

University of Washington students have created a system, the Wearable Low
Vision Aid (WLVA), that helps people with poor vision to navigate around
stationary objects. The inexpensive prototype consists of a backpack
containing a laptop computer that is connected to an image and display system
mounted on a pair of glasses. 

The imaging system contains a ring of 24 infrared, light-emitting diodes and
a camera. The diodes fire periodically while the camera collects infrared
video input from the user's field of view. Custom software compares the
diode-illuminated scene with the ambient scene in real time. 

Closer objects reflect more light than distant objects; if the closer objects
remain in view and grow in size, a collision is imminent. The WLVA recognizes
the danger and sends a signal to the computer, which determines the location
and type of object and triggers the raster display.  

The display is a vibrating, crystal fiber connected to a laser diode. The
fiber vibrates over 1,000 times/s, covering its entire scan area 60 times/s.
It traces a series of horizontal lines to form a complete, yet translucent,
"screen," while the laser fires only at certain points during the trace. Each
laser pulse equates to a single pixel, and from the WLVA user's perspective,
the final result is a familiar image. 

Visit http://www.nsf.gov/news/news_summ.jsp?cntn_id=100390&org=NSF&from=news
for more information.

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Heads-up display promises to help near-blind to navigate
From: EE Times - June 7, 2004 - page 6
By: R. Colin Johnson 

University of Washington students have turned a pair of Elvis Costello-style
eyeglasses and a backpack into a system that helps the near-blind navigate
around stationary objects. Their Wearable Low Vision Aid projects icons on
top of obstacles seen in a heads-up display, using a laser diode and a
vibrating crystal fiber made from components that cost less than $1. 

Read the entire article at:
http://www.eet.com/showArticle.jhtml?articleID=21401522

Link:
http://www.hitl.washington.edu/research/wlva/