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xerography

(Encyclopedia)xerography zərŏgˈrəfēˌ [key], also called electrophotography, method of dry photocopying in which the image is transferred by using the attractive forces of electric charges. A beam of light, us...

photostat

(Encyclopedia)photostat fōˈtəstătˌ [key], reproduction of any printed or simple black-and-white material, such as drawings or manuscripts, made by the Photostat, a photographic camera. While slower and more ex...

Carlson, Chester Floyd

(Encyclopedia)Carlson, Chester Floyd, 1906–68, American inventor; b. Seattle, Wash. A patent lawyer, he invented (1938) xerography, a method of electrostatic printing. For the next two decades he struggled to fin...

laser printer

(Encyclopedia)laser printer, a computer printer that produces high-resolution output by means of a process that is similar to photocopying. In place of reflected light from an image (as is used in xerography), a la...

selenium

(Encyclopedia)selenium səlēˈnēəm [key], nonmetallic chemical element; symbol Se; at. no. 34; at. wt. 78.96; m.p. 217℃; b.p. about 685℃; sp. gr. 4.81 at 20℃; valence −2, +4, or +6. Selenium is directly ...

photocopying

(Encyclopedia)photocopying, process whereby written or printed matter is directly copied by photographic techniques. Generally, photocopying is practical when just a few copies of an original are needed. When many ...

printing

(Encyclopedia)printing, means of producing reproductions of written material or images in multiple copies. There are four traditional types of printing: relief printing (with which this article is mainly concerned)...