The Full Wiki

Chester Carlson: Wikis


Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.


From Wikipedia, the free encyclopedia

Chester Floyd Carlson

Chester Carlson
Born February 8, 1906(1906-02-08)
Seattle, Washington,
United States
Died September 19, 1968 (aged 62)
Nationality United States
Fields Physicist, Inventor, Patent attorney
Known for Xerox, Xerography

Chester Floyd Carlson (February 8, 1906 – September 19, 1968) was an American physicist, inventor, and patent attorney born in Seattle, Washington.

He is best known for having invented the process of electrophotography, which produced a dry copy rather than a wet copy, as was produced by the mimeograph process. Carlson's process was subsequently renamed to xerography, a term that literally means "dry copy."


Early life

When Carlson was young, both his parents had tuberculosis and his father also suffered from arthritis of the spine (a common, age-related disease). Because of their illnesses, Carlson worked to support his family from an early age. His mother died when he was 17 and his father died when Carlson was 27.

Carlson once said, "Work outside of school hours was a necessity at an early age, and with such time as I had I turned toward interests of my own devising, making things, experimenting, and planning for the future. I had read of Thomas Alva Edison and other successful inventors, and the idea of making an invention appealed to me as one of the few available means to accomplish a change in one's economic status, while at the same time bringing to focus my interest in technical things and making it possible to make a contribution to society as well."


Transferring from Riverside Junior College, he earned his B.S. degree in Physics at the California Institute of Technology in 1930, and began working for Bell Telephone Laboratories in New York City as a research engineer. Finding the work dull and routine, Carlson transferred to the patent department. Laid off in 1933 during the Great Depression, he found a job as a clerk with a patent attorney near New York City's Wall Street. After about a year he got a better job at the electronics firm P. R. Mallory Company (founded by Philip Mallory, now known as Duracell), where he was promoted to head of the patent department. In 1936 he began to study law at night at New York Law School, receiving his LL.B. degree in 1939.

His training in patent law stood him in good stead later, when he began to make progress with the basic principles of electrophotography.

Early career

Carlson began thinking about reproducing print early in his career. When asked by author A. Dinsdal why he chose this field, Carlson said, "Well, I had had a fascination with the graphic arts from childhood. One of the first things I wanted was a typewriter—even when I was in grammar school. Then, when I was in high school I liked chemistry and I got the idea of publishing a little magazine for amateur chemists. I also worked for a printer in my spare time and he sold me an old printing press which he had discarded. I paid for it by working for him. Then I started out to set my own type and print this little paper. I don't think I printed more than two issues, and they weren't much. However, this experience did impress me with the difficulty of getting words into hard copy and this, in turn, started me thinking about duplicating processes. I started a little inventor's notebook and I would jot down ideas from time to time."

"There was a gap of some years, but by 1935 I was more or less settled. I had my job, but I didn't think I was getting ahead very fast. I was just living from hand to mouth, you might say, and I had just got married. It was kind of a hard struggle. So I thought the possibility of making an invention might kill two birds with one stone; it would be a chance to do the world some good and also a chance to do myself some good."

While doing patent work, Carlson often thought of how convenient it would be to have easily made copies of patent specifications. His job required the preparation of multiple copies for submission to the U.S. Patent Office, and they often took many tedious hours of drawing and re-typing. Photostats, while an alternative, were too expensive. Carlson knew there had to be a better way. He knew there had to be a quicker method and with time he would find it.

He also knew that the research laboratories of many companies were already working on chemical and thermal means of copying papers, so he began to think about different ways of doing the same thing. Months of research at the New York Public Library led him to photoconductivity, in which light can increase the electric conductivity of certain kind of materials under certain conditions. The basics of the process were simple in principle: when light and shadow strike an electrically charged plate of a certain material, the dark parts can attract an electrostatic or magnetic powder while the light part repels it. If the powder can be fused or melted to the page, it can then form a near-exact copy of the original paper. .....


It took Carlson 15 years to establish the basic principles of electrophotography, and he patented his developments every step along the way. He filed his first preliminary patent application on October 18, 1937. His early experiments, conducted with sulphur in his apartment kitchen, were smoky and smelly and he was soon encouraged to find another place. At about the same time, he developed arthritis of the spine, like his father. He pressed on with his experiments, however, in addition to his law school studies and his regular job.

To make things easier, he hired Otto Kornei, an immigrant physicist from Austria who had fled the Nazi regime there. They set up their laboratory in a back room of a house in Astoria, Queens, New York City.

On October 6, 1942, the Patent Office issued Carlson's patent on electrophotography.[1]

On October 22, 1938 they had their historic breakthrough. Kornei wrote the words 10.-22.-38 ASTORIA. in India ink on a glass microscope slide. The Austrian prepared a zinc plate with a sulfur coating, darkened the room, rubbed the sulfur surface with a handkerchief to apply an electrostatic charge, then laid the slide on the zinc plate, exposing it to a bright, incandescent light. They removed the slide, sprinkled lycopodium powder to the sulfur surface, softly blew the excess away, and transferred the image to a sheet of wax paper. They heated the paper, melting the wax off, and had their first near-perfect duplicate. After repeating the experiment several times, they celebrated by going out to lunch.

The road to his success -- or that for xerography's success -- had been long and filled with failure. From 1939 to 1944, his funding requests were turned down by more than twenty companies.[2] His next-to-last attempt to garner the interest -- and funds -- he needed to commercialize the physics was a meeting with the Department of the Navy. The Navy had a specific interest in the production of dry copies but they did not "see" what Carlson saw. As what may have become a last-ditch effort, he took his idea to the Battelle Memorial Institute in Columbus, Ohio, in 1942. Carlson met with Battelle's John S. Crout, General Manager and assistant to Director Clyde E. Williams. By using a glass rod, an animal pelt and carbon powder, Carlson demonstrated how the electric charge that developed on the glass rod (now named triboelectric charge, though generalized as a static charge) could be used to attract the carbon particles to it. Carlson convinced Crout, and Crout persuaded Williams and other Battelle directors to make a "substantial investment in development of the process". Between 1946 and 1953 Crout "negotiated the series of licensing contracts with the Haloid Company (which in 1961 changed its name to Xerox Corporation). To summarize, Carlson's idea was proved feasible by Battelle between 1942 and 1946, then the company that would become Xerox Corp. (Haloid) made it commercial between 1946 and 1953. It took almost another 20 years before Xerography put the last mimeograph machine in the storage closet. Carlson was persistent and he was a hard worker. The process he conceived made him wealthy and it made Battelle Memorial Institute wealthy. It also transformed copyright law and the way people work. The physics behind xerography continue to yield new technology such as the laser printer.


On October 22, 1948, ten years to the day after that first microscope slide was copied, the Haloid Company made the first public announcement of xerography. They made their first sale of the Haloid Xerox Copier in 1950. The company received a number of research grants from the Department of Defense to develop the process in the 1950s in recognition of a need for a photographic method that would work in a nuclear war environment. The company continued to improve the concept, producing the Xerox 914 in 1959 in Jackson Heights, Queens.[3] It was the first truly simple, push-button, plain-paper copier, and was so successful that it sold in only six months what the company had projected it would sell in the product's entire lifetime. In 1981 Carlson was inducted into the National Inventors Hall of Fame.

Later life

Carlson devoted his wealth to philanthropic purposes. He donated over $150 million to charitable causes and was an active supporter of the NAACP. On September 19, 1968, Carlson died of a heart attack in a New York movie theater.[4] Among the beneficiaries of his bequests were the New York Civil Liberties Union and Ian Stevenson's research into reincarnation at the University of Virginia.


  1. ^ US patent 2297691 "Electrophotography".
  2. ^ "Fascinating facts about Chester Carlson inventor of Xerography in 1938.". June 1, 2006. Retrieved 2009-11-09.  
  3. ^ Abadjian, Nick. "Inventors of Queens", Queens Tribune, May 22, 2003. Accessed December 17, 2007. "Carlson, a Jackson Heights resident, worked as a lab researcher for a year and got laid off."
  4. ^ "Chester Floyd Carlson Biography". Retrieved 2009-11-09.  

Further reading

David Owen, Copies in Seconds: How a Lone Inventor and an Unknown Company Created the Biggest Communication Breakthrough Since Gutenberg - Chester Carlson and the Birth of the Xerox (New York: Simon and Schuster, 2004) ISBN 0-7432-5117-2, ISBN 0-7432-5118-0

External links



Got something to say? Make a comment.
Your name
Your email address