Phototypesetting was a method of setting type, rendered obsolete with the popularity of the personal computer and desktop publishing software, that used a photographic process to generate columns of type on a scroll of photographic paper. Typesetters used a machine called a phototypesetter, which would quickly project light through a film negative image of an individual character in a font, through a lens that would magnify or reduce the size of the character onto photographic paper, which would collect on a spool in a light-tight canister. The photographic paper or film would then be fed into a processor, a machine that would pull the paper or film strip through two or three baths of chemicals, where it would emerge ready for paste up or film make-up.
Phototypesetting machines projected characters onto film for offset printing. This "cold type" technology could be used in office environments where "hot metal" machines (the Mergenthaler Linotype, the Harris Intertype and the Monotype) could not. The use of phototypesetting grew rapidly in the 1960s when software was developed to convert marked up copy, usually typed on paper tape, to the codes that controlled the phototypesetters. The Photon Corporation in Cambridge, Mass. developed equipment based on the Lumitype of Rene Higonnet and Louis Moyroud. Mergenthaler produced the Linofilm using a different design and Monotype produced Monophoto. Other companies followed with products that included Alphatype and Varityper. The major advancement presented by the Phototypesetting machines over the Linotype machine "hot type" machines was the shift in usage of no metal in the Phototypesetting machines. The "cold type" machine continued in the automation that was started by the Linotype machines.
To provide much greater speeds, the Photon Corporation produced the ZIP 200 machine for the MEDLARS project of the National Library of Medicine and Mergenthaler produced the Linotron. The ZIP 200 could produce text at 600 characters per second using high speed flashes behind plates with images of the characters to be printed. Each character had a separate xenon flash constantly ready to fire. A separate system of optics positioned the image on the page.
A technical review of a moderate cost solution to the CRT phototypesetting avoiding the necessity of expensive high resolution CRT tubes and the ultimate in circuitry. Representing a combination of high resolution character storage by optical means, together with electronic scanning and presentation, the Linotron 505 combined the optimum features of proven systems to achieve flexibility and productive speed without sacrifice of typographic quality.