Richard Farrell Kinnaird, a pioneer in optical design technology who helped to develop optics for U.S. spy and space programs, died on Tuesday in Ellsworth.

He was 89.

Kinnaird received bachelor’s degrees in physics and astronomy from Millsaps College in Jackson, Miss., and in 1936 earned a master’s in astronomy from the University of Chicago. Upon completing his graduate work, Kinnaird joined Northwestern University as a research assistant at the Dearborn Observatory where he worked on the stellar photometer project to make faster measurements of the brightness of stars possible.

After a short time designing optics for Bell & Howell movie cameras, Kinnaird joined the Perkin-Elmer Corp., which became an important government contractor doing optical science and engineering for new inventions during World War II. He was project engineer for optical gun sights in bombers, special tracking cameras, telephoto lenses and range finders for the U.S. Army and Air Force.

He also worked on development of the 40-inch T-5 telephoto lens that was used to film the bombing of Hiroshima and Nagasaki in 1945. The company received a citation from Gen. Hap Arnold for its significant contributions to the war effort.

After the war, at new headquarters in Norwalk, Conn., Kinnaird assembled a team of scientists and engineers from all over the world to develop laser and infrared technologies. These efforts resulted in an infrared spectrometer, the beginning of a new industry for analytical instruments. He also designed the optics for the first optical-electronic bombsight to be installed in a high-speed aircraft, the B-47.

His work on secret government projects continued during the Cold War with the development of cameras for the U-2 spy plane. Perkin-Elmer made aerial landscape photography possible from 80,000 feet.

Kinnaird also provided the vision for the design of new photographic systems. With longtime colleague Dr. James Baker of Harvard, he helped to refine lenses for the first efforts of computer-aided design, now its own industry. He was also an expert in the use of Rare Earth Glass for optics, a new composite of much greater quality than standard optical glass.

Above all, Kinnaird was a practical engineer. During the early stages of the Mercury space program in the 1960s, he was working out the details of a periscope requested by NASA so the astronauts could see out of the capsule. He suggested they put a window in the spacecraft. A porthole was added so Alan Shepard could see Earth on his first flight. In his last years with Perkin-Elmer, Kinnaird worked extensively with NASA on various projects for the Mercury, Skylab and Apollo programs.

In retirement, Kinnaird continued his lifelong interest in mathematics by doing extensive theoretical work in the fields of statistics and probability. While calculating his gas mileage, he uncovered an error in the historic Method of Least Squares that had persisted for several hundred years. He wrote and presented papers on the subject, including an article in The Journal of the American Physical Society.

Kinnaird is survived by his wife, the former Margaret Evelyn Thompson of Blue Hill; a brother Robert Newell Kinnaird Jr. of Hattiesburg, Miss.; a brother-in-law, George Brueske of Arcata, Calif.; two sons, Robert of Ridgefield, Conn., and Richard of Bethesda, Md.; and four grandchildren.