
1) Display technology
Found on
https://www.crosswordclues.com/clue/led-display

An LED display is a flat panel display, which uses an array of light-emitting diodes as a video display. An LED panel is a small display, or a component of a larger display. They are typically used outdoors in store signs and billboards, and in recent years have also become commonly used in destination signs on public transport vehicles or even as...
Found on
http://en.wikipedia.org/wiki/LED_display

One or more LEDs used to indicate the operational status of a piece of electronic equipment, or the varying level of a signal being processed, or simply peak or VU levels. The series of LEDs must be driven by a circuit that senses these levels or conditions, turning on only the appropriate LEDs at each moment. (WW)
Found on
http://www.encyclo.co.uk/local/22286
No exact match found.