October 22

1938: Xerox This

Inventor Chester Carlson produces the first Xerox copy.

Engineer Carlson worked in a corporate patent department, where hand-copying documents or sending them out to be photographed caused delays. Carlson conceived a dry-copying process using photoconductivity: Light striking the surface of certain materials increases electron flow. Project an image onto a photoconductive surface, and current will flow only where light strikes.

Four years of tinkering in his kitchen and in his mother-in-law’s beauty salon yielded results in October 1938. Research assistant Otto Kornei put a sulfur coating on a zinc plate and rubbed it with a handkerchief to produce an electrostatic charge. A glass slide marked 10-22-38 ASTORIA was placed on the plate in a darkened room and illuminated with a bright lamp for a few seconds. Powder from waxy moss spores was sprinkled on the sulfur and then blown off. There it was: a near-perfect mirror image of the writing.

Carlson patented his invention but needed development money. After rejections from IBM, Kodak, General Electric, RCA, and others, he ceded a 60 percent stake to Battelle Memorial Institute, which assigned physicist Roland Schaffert to perfect electrophotography. Battelle licensed the technology to Haloid of Rochester, New York. Battelle and Haloid publicly demonstrated the process on October 22, 1948, precisely ten years after Carlson’s dry run. A professor devised the word xerography from the Greek for “dry writing,” and Haloid soon became Xerox.

The photocopiers introduced in 1949 were a logistical mess: it took fourteen steps and forty-five seconds to make one copy, maximum twelve copies per exposure. The company had its first big hit in 1959 with the Xerox 914.

The Xerox machine had a profound cultural influence. It also made Carlson rich, earning today’s equivalent of a billion dollars, two-thirds of which he gave to charity.—RA