Vector monitor

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Vector displays or vector monitors is a display device used for early computers. It is a type of CRT similar to the oscilloscope but typically using magnetic, rather than electrostatic, deflection.^{[citation needed]} Here, the beam traces straight lines between arbitrary points, repeatedly refreshing the display as quickly as possible.

Vector displays for computers did not noticeably suffer from the display artifacts of Aliasing and pixelation, but were limited in that they could display only a shape's outline (advanced vector systems could provide a limited amount of shading), and only a limited amount of crudely-drawn text (the number of shapes and/or textual characters drawn was severely limited, because the speed of refresh was roughly inversely proportional to how many vectors needed to be drawn).

Vector displays were used for head-up displays in fighter aircraft, because of the brighter displays that can be achieved by moving the electron beam more slowly across the phosphorus. Brightness is critical in this application because the display must be clearly visible to the pilot in direct sunlight.

Vector monitors were also used by some late-1970s to mid-1980s arcade games such as Asteroids.^[1] Atari used the term Quadrascan to describe the technology when used in their games.

[edit] Color displays

Some vector monitors are capable of displaying multiple colors, using either a typical tri-color CRT, or two phosphor layers (so-called "penetration color").^{[citation needed]} In these dual-layer tubes, by controlling the strength of the electron beam, electrons could be made to reach (and illuminate) either or both phosphor layers, typically producing a choice of green, orange, or red. Atari used the term Color Quadrascan to describe this colour version when used in their games.

[edit] References

1. ^ Van Burnham (2001). Supercade: A Visual History of the Videogame Age, 1971-1984. MIT Press. ISBN 0262524201.