Blodgett was hired by the General Electric company as a research scientist in 1918 after receiving a master's degree from the
University of Chicago. She was the first woman to work as a scientist for General Electric Laboratory in Schenectady, NY. She often worked with
Irving Langmuir, who had pioneered a technique for creating single-molecule thin films on the surface of water. Blodgett and Langmuir explored the application of similar techniques to lipids, polymers, and proteins, creating
monomolecular coatings designed to cover surfaces of water, metal, or glass. These special coatings were oily and could be deposited in layers only a few
nanometers thick. In 1935, Blodgett extended Langmuir's work by devising a method to spread multiple layers of a monomolecular coating, one layer at a time, onto glass or metal. By repeatedly dipping a metal plate into water covered by a layer of a long-chain fatty acid, she was able to stack layers onto the plate with molecular precision. The apparatus which she used and refined is known as the
Langmuir–Blodgett trough. Blodgett used barium stearate to cover glass with 44 monomolecular layers, making the glass more than 99% transmissive and creating "invisible" glass. The visible light reflected by the layers of film canceled the reflections created by the glass. Other types of films employing harder antireflective coatings or etched surfaces proved more useful for applications such as camera lenses. Blodgett also invented a color gauge, a method to measure the thickness of molecular coatings on glass to the nearest one millionth of an inch. The gauge employed the concept that different thicknesses of coatings are different colors. While examining the layering of
stearic acid on a glass plate, she realized that the addition of each layer, about 2/10,000,000 inch thick, reliably changed the color of the plate. Before her invention, the best measurement instruments were only accurate to a few thousandths of an inch. Her glass "ruler" much more precisely showed the progression of colors and their corresponding thicknesses. Measuring thickness became as simple as matching colors. The color gauge was marketed for a time by General Electric. Blodgett and Langmuir also worked on improvements to the light bulb. Their studies on electrical discharges in gases helped lay the foundations for
plasma physics. Blodgett was issued eight U.S.
patents during her career. She was the sole inventor on all but two of the patents, working with
Vincent J. Schaefer as co-inventor. Blodgett published over 30 technical papers in various scientific journals. Her research also included the investigation of methods for
deicing aircraft wings, and improving smokescreens during WWII. ==Personal life==