Dr. Knowlton remained at Bell Labs until 1982, experimenting with every part from computer-generated music to technologies that allowed deaf people to read sign language over the phone. He later joined Wang Laboratories, where, within the late-Nineteen Eighties, he helped develop a notebook computer that allow users annotate documents with synchronized voice messages and digital pen strokes.
In 2008, after retiring from tech research, he joined a magician and inventor named Mark Setteducati in making a jigsaw puzzle called Ji Ga Zo, which may very well be arranged to resemble anyone’s face. “He had a mathematical mind combined with an incredible sense of aesthetics,” Mr. Setteducati said in a phone interview.
Along with his son Rick, Dr. Knowlton is survived by two other sons, Kenneth and David, all from his first marriage, which resulted in divorce; a brother, Fredrick Knowlton; and a sister, Marie Knowlton. Two daughters, Melinda and Suzanne Knowlton, also from his first marriage, and his second wife, Barbara Bean-Knowlton, have died.
While at Bell Labs, Mr. Knowlton collaborated with several well-known artists, including the experimental filmmaker Stan VanDerBeek, the pc artist Lillian Schwartz and the electronic-music composer Laurie Spiegel. He saw himself as an engineer who helped others create art, as prescribed by Mr. Rauschenberg’s E.A.T. project.
But later in life he began creating, showing and selling art of his own, constructing traditional analog images with dominoes, dice, seashells and other materials. He belatedly realized that when engineers collaborate with artists, they grow to be greater than engineers.
“In one of the best cases, they grow to be more complete humans, partly from understanding that each one behavior comes not from logic but, on the bottommost level, from intrinsically indefensible emotions, values and drives,” he wrote in 2001. “Some ultimately grow to be artists.”