Liquid crystal display backlights

FIGURE 10.7 Power consumption simulation for a 2.2-in. full-color OLED display using Universal Display s phosphorescent OLEDs, small-molecule fluorescent devices, and polymer OLEDs along with a comparison of the power consumed by an active-matrix liquid crystal display backlight. R G B= 3 6 1, 50% polarizer efficiency, and 30% of pixels lit. (From Mahon, J.K., Adv. Imaging, June, 28, 2003. With permission.)... 

For example, active-matrix backplanes for reflective displays using electrophoretic media is a potential application for large-area electronics. Electrophoretic media are usually charged colored particles suspended in an insulating fluid [35-37]. When the fluid is held in an electric field between two conductive plates, the particles will move between the plates creating a dark or a reflective state. Because the contrast in an electrophoretic display is because of reflection, no backlight is required and the display has relatively low-power consumption compared with a transmissive liquid-crystal display. 

At Siemens the effort is directed to develop devices for use in backlighting for the keys on mobile telephones or for the liquid crystal display devices. Polymers displays... 

NANOPOROUS ALUMINA PANELS FOR BACKLIGHT ENHANCEMENT IN LIQUID CRYSTAL DISPLAYS... 

In order to show how these lamps are used, it is necessary to describe liquid crystal displays (LCD). We will not describe this technology thoroughly since it does not directly relate to the use of phosphors in the display, except in the fluorescent lamps used for "backlighting" the LCD. A "liquid crystal"- (LC) is an organic compound whose molecules align themselves with an applied electric field. An LC substance flows as a liquid but maintains some of the ordered structure characteristic of a crystal. 

Rare-earth phosphors are widely used for general illumination (fluorescent lamps) and displays (cathode ray tube, backlights for liquid crystal displays, and plasma display panels). Major rare earths present in the phosphor are cerium, europium, and terbium, which are optically active because of the... 

Ir complexes were also used to develop white OLEDs (WOLEDs) for large-scale production of solid-state light sources and backlights in liquid-crystal displays. Several device architectures have been introduced to achieve high brightness and efficiency in WOLEDs. By controlling the recombination current within individual... 

Xie R-J, Hirosaki N, Takeda T (2009) Wide color gamut backlight for liquid crystal displays using three-band phosphor-converted white light-emitting diodes. Appl Phys Express 2 (2) 022401... 

Instrument and computer applications of these discrete devices include indicator lamps, numeric and alphanumeric displays, and LED backlighting of liquid crystal displays. Higher performance LEDs are often used for the backlighting application. Consumer electronics applications (audio equipment, home appliances, clocks, radios, toys, etc.) include discrete indicator lamps and numeric and alphanumeric displays. 

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