Vane display

An inactive vane display on the Creek Turnpike in Tulsa, Oklahoma.

An active vane display at Penn Station in New York City.

A vane display is a type of 7-segment display. Unlike LED and VFD segmented displays, vane displays are composed of seven physical surfaces, typically painted white, but occasionally other colors, such as yellow or fluorescent green. If a segment is to be displayed as "off", it will be rotated so that its edge faces forward, with the painted surface pointing upward and not visible. A segment that is to be displayed as "on" will be rotated so that the painted surface is shown.

Vane displays operate in a similar manner to flip-disc displays, in that the segments are quickly moved using electromagnets. Some variants used where the display need not necessarily be changed quickly use electric motors to rotate the displays in and out of place.

Vane displays have been used often in game shows, or on scoreboards in sports arenas. Like eggcrate displays, they are not washed out by bright lights such as those found in a television studio. Another benefit of the vane display is that if the power supply is lost, the display will continue to show whatever the last value was before power was cut. However, like flip-disc displays, if a large number of elements must be changed at the same time, the flipping displays may present a significant amount of noise.

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