Katharine Burr Blodgett Invents Non-Reflective Glass

Katherine Burr Blodgett (1898-1979) was a woman of many firsts. She was the first female scientist hired by General Electric’s Research Laboratory in Schenectady, New York (1917) as well as the first woman to earn a Ph.D. in Physics from Cambridge University (1926). She was the first woman to receive the Photographic Society of America Award, and the American Chemical Society honored her with the Francis P. Garvin Medal. Her most notable discovery was in how to produce non-reflective glass. Early Life of Katharine Burr Blodgett Blodgetts father was a patent lawyer and head of the patent department at General Electric. He was killed by a burglar a few months before she was born but left enough savings that the family was financially secure. After living in Paris, the family returned to New York where Blodgett attended private schools and Bryn Mawr College, excelling at mathematics and physics. She got her masters degree from the University of Chicago in 1918 with a thesis on the chemical structure of gas masks, determining that carbon would absorb most poisonous gasses. She then went to work for the General Electric Research Lab with  Nobel Prize winner  Dr. Irving Langmuir. She completed her Ph.D. at Cambridge University in 1926. Research at General  Electric Blodgett’s research on monomolecular coatings with  Langmuir led her to a revolutionary discovery. She discovered a way to apply the coatings layer by layer to glass and metal. These thin films naturally reduce glare on reflective surfaces. When layered to a certain thickness, they completely cancel out the reflection from the surface underneath. This resulted in the world’s first 100 percent transparent or invisible glass Katherine Blodgett’s patented film and process (1938) has been used for many purposes including limiting distortion in eyeglasses, microscopes, telescopes, camera, and projector lenses.   Katherine Blodgett received U.S patent #2,220,660 on March 16, 1938, for the Film Structure and Method of Preparation or invisible, nonreflective glass. Katherine Blodgett also invented a special color gauge for measuring the thickness of these films of glass, since 35,000 layers of the film only added up to the thickness of a sheet of paper. Blodgett also made a breakthrough in developing smoke screens during World War II. Her process allowed less oil to be used as it was vaporized into molecular particles. In addition, she developed methods for deicing airplane wings. She published dozens of scientific papers over the course of her long career. Blodgett retired from General Electric in 1963.  She did not marry and lived with Gertrude Brown for many years. She acted in the Schenectady Civic Players and lived on Lake George in the Adirondack Mountains.  She died at home in 1979. Her awards include the Progress Medal from the Photographic Society of America, Garvan Medal of the American Chemical Society, American Physical Society Fellow, and Boston First Assembly of American Women of Achievement honored scientist. In 2007 she was inducted into the National Inventors Hall of Fame. Patents Granted to Katharine Burr Blodgett U.S. Patent 2,220,860: 1940: Film Structure and Method of PreparationU.S. Patent 2,220,861: 1940: Reduction of Surface ReflectionU.S. Patent 2,220,862: 1940: Low-Reflectance GlassU.S. Patent 2,493,745: 1950: Electrical Indicator of Mechanical ExpansionU.S. Patent 2,587,282: 1952: Step Gauge for Measuring Thickness of Thin FilmsU.S. Patent 2,589,983: 1952: Electrical Indicator of Mechanical ExpansionU.S. Patent 2,597,562: 1952: Electrically Conducting LayerU.S. Patent 2,636,832: 1953: Method of Forming Semiconducting Layers on Glass and Article Formed Thereby