George H. Heilmeier, 77, a Philadelphia native who created the first liquid-crystal displays for calculators, watches, and computers while working for RCA Laboratories, died Monday, April 21, of a stroke at a hospital in Plano, Texas.

Mr. Heilmeier graduated from Lincoln High School and the University of Pennsylvania, and then earned advanced degrees including a doctorate in solid state materials and electronics from Princeton University.

In the 1960s, he joined RCA Laboratories in New Jersey, where he worked with electro-optic effects in liquid crystals to create the liquid-crystal display. Three decades later, Mr. Heilmeier was awarded the National Medal of Science by President George H. W. Bush for his achievement.

In 1970, Mr. Heilmeier left Yardley, Bucks County, for Washington to become a special assistant to the secretary of defense. He went on to head up the Defense Advanced Research Projects Agency, helping to develop the stealth aircraft, space-based lasers, reconnaissance systems, and infrared technology.

After stints at various technology companies around the nation, he retired in 1997 and moved to Dallas.

Surviving are his wife, the former Janet Faunce; a daughter, Beth Jarvie; and three grandchildren.

A memorial service will be held Monday, May 12, in Plano.