Chester Carlson

Curators’ Corner

Chester Carlson

Chester Carlson is the inventor of electrophotography (or xerography) which is a dry photocopying technique. He invented the technique in 1938 and in 1942 it was patented.  Carlson’s invention is the precursor to today’s photocopiers and resulted in the first commercial automatic copier, the Xerox 914, released by Haloid/Xerox in 1960.

Initially the process was very cumbersome and required a significant amount of time.  The innovation combined electrostatic printing with photography and required several manual processing steps with flat plates for 18 years. The term xerography means “dry writing” and it gained preference over electrophotography as the process went commercial.

Carlson was born on February 8, 1906 and moved to Mexico as a child due to his parents poor health. There he became interested in writing and the use of the printing press; later moving to California in high school he worked at a printing company and there he became frustrated with the inability to reproduce quality copies from the machinery in the shop.

Carlson attended Riverside Junior College and then transferred to California Institute of Technology-Caltech-where he graduated in 1930 with a degree in Physics.  Carlson’s worked at Bell Telephone Laboratories in New York City as a research engineer, but found the work to be dull and routine.  After a year, he transferred to the patent department as an assistant to one of the company’s patent attorneys. Carlson wrote over 400 ideas for new inventions in his personal notebooks while working at Bell Labs.

After another job in New York, Carlson landed at the electronics firm, P. R. Mallory Company, where he was given the title Head of the Patent Department.  While working at P. R. Mallory, Carlson began attending law school at New York University where he was awarded his LL.B. in 1939.  It was during law school that Carlson resolved to find a successful method to reproduce prints because he was tired of hand writing excerpts from law books and journals.

Carlson began his work experiments at home in his apartment kitchen often to disastrous results—odors, fires, explosions and ink stains were quite common.  He moved Astoria, Queens and hired Otto Kornei, an out-of-work Austrian physicist.  Finally in 1938 after years of attempting to perfect the process they were successful.

They used a zinc plate with a sulfur coating in a dark room and rubbed the sulfur surface with a cotton handkerchief to create an electrostatic charge, then he laid the slide on the plate, exposing it to a bright, incandescent light. After removing the slide, they sprinkled lycopodium powder to the sulfur surface and then transferred the image to a sheet of wax paper.  The wax paper was heated to melt and the lycopodium adhered to the copy producing the first xerographic copy. Carlson continued his successful career with Xerox at their Rochester, NY location.   In 1968, Fortune magazine ranked Carlson among the wealthiest people in America.  Carlson passed away on September 19, 1968.