Patent for Xerox Technology Issued October 6, 1942

Electrophotography was Precursor of the First Office Copier
Press Release

Maria V. Hernandez at


Chester F. Carlson, considered the father of xerographic printing, received patent #2,297,691 on October 6, 1942 for electrophotography. Carlson's invention, the first method of making images by dry copying, evolved from his desire to eliminate hand reproduction of patent specifications and drawings at the electronics firm where he worked as a physicist. In 1947, he assigned the commercial rights to his invention to the Haloid Company, later renamed the Xerox Corporation. Carlson, who was born in Seattle, Wash., was inducted into the National Inventors Hall of Fame in 1981.

This patent, as well as the more than 6 million patents issued since the first in 1790, can be seen on the Department of Commerce's United States Patent and Trademark Office website at

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