Display

A display is a piece of hardware which can display an image to the user; the may be monochrome, although now they are almost all colour.

The first displays used CRTs, but since they were vacuum tubes, they took up considerable volume. Still, they were the mainstay of visual displays up through the early days of bit-mapped displays.

When it became possible to fabricate liquid crystal displays with many pixels in large arrays, they were the only viable display technology for use in lap-top personal computers, and that drove their development. LCD displays rapidly became the display of choice once they became economically competive.

LCDs needed a backlight, which was generally provided by a fluorescent light driven by a high-voltage power supply, both of which had a tendency to fail.

Thus, when the invention of the blue LED permitted the creation of displays consisting of arrays of LEDs, those rapidly because the display technology of choice.