A vector monitor or vector display is a display device used for early computers. It is a type of CRT, similar to the oscilloscope, but typically uses magnetic, rather than electrostatic, deflection. Here, the beam traces straight lines between arbitrary points, repeatedly refreshing the display as quickly as possible.
Vector displays for computers did not 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).
Notable among vector displays were Tektronix large-screen computer terminals that used direct-view storage CRTs. Storage meant that the display, once written, would persist for several minutes before needing an erase and redraw cycle. (The CRT had at least one flood gun, and a special type of display screen, more complicated in principle than a simple phosphor.)
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 phosphors. 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 video game arcades.
Hewlett-Packard made a large-screen fast vector monitor, which they called an X-Y display. It used a wide-angle electrostatically-deflected CRT that was about as compact as a magnetic-deflection CRT. Instead of the deflection plates of a typical CRT, it had a unique structure they called an electrostatic deflection yoke, with metallized electrodes inside a glass cylinder.
Some vector monitors are capable of displaying multiple colors, using two phosphor layers (so-called "penetration color"). 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 color version when used in their video game arcades.
Tektronix made color oscilloscopes for a few years using penetration CRTs, but they apparently weren't in great demand.