A liquid crystal display (LCD) is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals. Liquid crystals do not emit light directly.
LCDs are available to display arbitrary images (as in a general-purpose computer display) or fixed images which can be displayed or hidden, such as preset words, digits, and 7-segment displays as in a digital clock. They use the same basic technology, except that arbitrary images are made up of a large number of small pixels, while other displays have larger elements.
LCDs are used in a wide range of applications including computer monitors, televisions, instrument panels, aircraft cockpit displays, and signage. They are common in consumer devices such as video players, gaming devices, clocks, watches, calculators, and telephones, and have replaced cathode ray tube (CRT) displays in most applications. They are available in a wider range of screen sizes than CRT and plasma displays, and since they do not use phosphors, they do not suffer image burn-in. LCDs are, however, susceptible to image persistence.
The LCD screen is more energy efficient and can be disposed of more safely than a CRT. Its low electrical power consumption enables it to be used in battery-powered electronic equipment. It is an electronically modulated optical device made up of any number of segments filled with liquid crystals and arrayed in front of a light source (backlight) or reflector to produce images in color or monochrome. Liquid crystals were first developed in 1888. By 2008, worldwide sales of televisions with LCD screens exceeded annual sales of CRT units; the CRT became obsolete for most purposes.
Read more about Liquid Crystal Display: Overview, History, Illumination, Connection To Other Circuits, Passive and Active-matrix, Quality Control, Zero-power (bistable) Displays, Specifications, Military Use of LCD Monitors, Advantages and Disadvantages
Famous quotes containing the words liquid, crystal and/or display:
“What slender Youth bedew’d with liquid odours
Courts thee on Roses in some pleasant Cave,”
—Horace [Quintus Horatius Flaccus] (65–8)
“We have ... a thirst unquenchable, to allay which he has not shown us the crystal springs. This thirst belongs to the immortality of Man.... It is no mere appreciation of the Beauty before us—but a wild effort to reach the Beauty above.”
—Edgar Allan Poe (1809–1849)
“Life is extraordinarily suave and sweet with certain natural, witty, affectionate people who have unusual distinction and are capable of every vice, but who make a display of none in public and about whom no one can affirm they have a single one. There is something supple and secret about them. Besides, their perversity gives spice to their most innocent occupations, such as taking a walk in the garden at night.”
—Marcel Proust (1871–1922)