A daisy wheel printer is a type of computer printer that produces high-quality type, and was habitually referred to during the 1980s as a letter-quality printer. There were also, and still are, daisy wheel typewriters, based on the same principle. The system used a tiny wheel with each letter printed on it in raised metal or plastic. The printer turns the wheel to line up the proper letter under a solitary pawl which then strikes the back of the letter and drives it into the paper. In many respects the daisy wheel is similar to a standard typewriter in the way it forms its letters on the page, differing only in the details of the mechanism. As with daisy wheel typewriters and typeball-based Selectrics, diverse fonts could be supported during replacing the daisy wheel. Appropriately-written software would stop the printer at the font change, space to the center of the carriage, and prompt the user to change the wheel before proceeding.
The Xerox Diablo D25 integrated this functionality in the printer’s hardware. While realistic for most needs, printing a document which commonly alternated between italics and plain text would become an arduous task. Bold face could typically be supported, though found mostly on later and high-end daisywheel printers. When instructed to print in bold, some printers would twice or triple strike a given character, and some servo-based printers would very slightly advance the carriage for a wider (and therefore blacker) character. Still others would perform a carriage return (without a line feed) to return to the beginning of the line, space through all non-bold text, and restrike each bolded character - the inherent imprecision in attempting to restrike on accurately the same spot after a carriage return providing the same effect as a far more expensive servo-based printer, though with the exclusive effect that as the printer aged, bold text would become bolder. Daisy wheel printers were fairly common in the 1980s, but were always less popular than dot matrix printers (ballistic wire printers) due to higher cost and the dot-matrix’s ability to print graphics and different fonts. Most dot-matrix printers were also considerably faster than competing daisy wheel printers, as each character required that the wheel be rotated to a new position.
The Xerox Diablo D25 integrated this functionality in the printer’s hardware. While realistic for most needs, printing a document which commonly alternated between italics and plain text would become an arduous task. Bold face could typically be supported, though found mostly on later and high-end daisywheel printers. When instructed to print in bold, some printers would twice or triple strike a given character, and some servo-based printers would very slightly advance the carriage for a wider (and therefore blacker) character. Still others would perform a carriage return (without a line feed) to return to the beginning of the line, space through all non-bold text, and restrike each bolded character - the inherent imprecision in attempting to restrike on accurately the same spot after a carriage return providing the same effect as a far more expensive servo-based printer, though with the exclusive effect that as the printer aged, bold text would become bolder. Daisy wheel printers were fairly common in the 1980s, but were always less popular than dot matrix printers (ballistic wire printers) due to higher cost and the dot-matrix’s ability to print graphics and different fonts. Most dot-matrix printers were also considerably faster than competing daisy wheel printers, as each character required that the wheel be rotated to a new position.
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