Phototypesetters, Continued
Typesetter
generations
Third-
generation
typesetters
Electromechan-
ical typesetters
The term generation classifies significant advancements in phototypesetter
technology. The first-generation phototypesetters closely resembled
machines used to cast hot type. Second-generation phototypesetters set type
by photographic projection through a font. Third-generation machines
reproduce letters on the face of a cathode-ray tube (CRT) and fourth-
generation equipment uses raster scan technology and fiber optics. Third-
generation phototypesetters still exist in Navy Graphics shops.
Third-generation phototypesetters use cathode-ray tube technology. There
are two basic categories of CRT typesetters. The first category,
electromechanical typesetters, scans a photographic master stored on grids
and strikes an image onto the face of a cathode-ray tube. This image then
passes through a lens to photographic film or paper. A letter is rescanned
each time it is used. This process is referred to as “on the fly. ” The second
category typesetter stores the font as a digital representation; a letter is
scanned only once and enters the machines memory for subsequent use.
Electromechanical typesetters may produce display or body type. They are
hand-operated by direct keystrokes. Newer machines may have magnetic
disk or tape memory and/or OCR scanning capabilities. Different type styles
and sizes are available for enlargement, reduction, or same-size reproduction.
The typesetter scans a photographic master each time a letter is used and
transfers the image on the fly to the face of a CRT screen or photosensitive
film/paper.
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