 Computer professors don't often win Oscars. But last February,
Henrik Wann Jensen, an assistant professor in the Jacobs
School of Engineering, walked off with one of the precious little
statuettes. Along with two former colleagues, Stanford University
professor Pat Hanrahan and Cornell University assistant professor
Stephen Marschner, Jensen was recognized at the Academy's Technical
Achievement awards in Pasadena, Calif., for “pioneering research
in simulating subsurface scattering of light in translucent materials.”
The creators of previous
generations of computer graphics assumed that the light that was
shone on a surface reflected back from the same point. This made
translucent material such as eyes, skin and teeth appear hard. After
studying the medical research, Jensen realized that light penetrates
the surface of skin and scatters. The photons then reflect out at
varying angles.
“This scattering effect below the surface was understood
as a medical phenomenon,” says Jensen, “but wasn't incorporated
into computer graphics until our model, which mathematically accounts
for the way those photons scatter.”
Movies such as Lord of
the Rings and Terminator 3 have used Jensen's technology to create
realistic-looking skin and more lifelike creatures. So
next time you marvel at Gollum, remember that those photons penetrating
his skin and scattering are actually just complex algorithms.
Or maybe it's just best to marvel.  |
