Theodore E. Cohn, 64; His Eye Expertise Led to Better Warning Signals

Theodore E. Cohn, 64, a UC Berkeley professor of optometry and bioengineering and a leading researcher in signal detection theory, died May 25 at Alta Bates Hospital in Oakland after a three-year battle with leukemia.

For most of the last 15 years, Cohn worked in the field of transportation engineering, applying his knowledge of vision science to solve practical problems. With his understanding of the way the eye detects visual signals and passes that information to the brain, he was able to develop various kinds of warning systems that provide faster human reaction times.

Inventions by Cohn and his research team included a cone-shaped emergency warning light for highway work zone vehicles and a light bar that indicates a vehicle is braking. One of his final projects was finding ways to make railroad crossings safer.

Cohn, who was born in Highland Park, Ill., earned a bachelor’s degree in electrical engineering from MIT and three degrees at the University of Michigan: a master’s in bioengineering, a master’s in mathematics and a doctorate in bioengineering.

His interest in signal detection began in college. He joined the Berkeley faculty in 1970 as an assistant professor of physiological optics and spent his entire professional career with the University of California.