|Flat panel television|
|Tuesday, 29 August 2006|
The television industry is beginning to use flat panel displays to replace cathode ray tube (CRT) technologies. Nowadays, flat panels have been widely employed in TV sets to replace the conventional spherical/parabolic panels, for enhanced visibility and reduction of glare due to reflection of external light. To address the inherent drawbacks of CRTs, alternative display technologies have been developed. These technologies include liquid crystal display (LCD), both passive and active matrix, electroluminescent display (ELD), plasma display panel (PDP), vacuum fluorescent display (VFD) and field emission display (FED). When compared to a spherical panel, a flat panel offers numerous advantages. A flat panel tends to be preferred to a conventional spherical panel because of customers' increasing demand for high resolution and large-size screen. Flat panel displays provide the best choice for constructing seamless tiled screens. The flat panel displays can reduce image distortion, minimize eye fatigue and provide a wide range of visibility. A flat panel display apparatus is lighter and smaller than a CRT display apparatus and has a low power consumption. Because of their light weight, small footprint, relatively sharp resolution, and low power consumption, flat panel displays enjoy wide appeal as television screens, computer screens, electronic game displays, avionics or vehicular displays, and as displays in a variety of other applications. Flat panel displays typically include a flat panel on which a matrix of cells formed between two glass substrates is arranged, a PCB module for driving the flat panel, and a case for protecting and integrating these elements. Flat-panel displays include backlighted and self-lighted displays. Liquid crystal displays (LCDs) are the most common backlighted displays.
A flat panel display is an organic light-emitting device that is able to be competitively priced. An organic light-emitting device is capable of being a light, thin, short and small display device since it has a fast response rate, superior luminance and a simple structure compared to a liquid crystal display light receiving device. A plasma display panel, a liquid crystal display and a light emitting diode display belong to the family of flat panel display devices. Among the displays, the LCD, which is generally utilized, is used as a display for a portable terminal as well as for a desktop computer. A color plasma display panel is a display in which ultraviolet rays are produced by gas discharge to excite phosphors so that visible lights are emitted therefrom to perform a display operation. Depending upon a discharge mode, the color PDP is classified into an AC (alternating current) or a DC (direct current) type. The AC plasma display is superior to the DC type in luminance, luminous efficiency, and lifetime. Flat panel display devices have excellent characteristics of light weight and low power consumption. An electroluminescent display (ELD) device is an emissive display device using an electroluminescent (EL) phenomenon that light is emitted from a luminescent layer when an electric field is applied. The ELD device can be classified into inorganic and organic types according to a source generating an excitation of carriers. Especially, an inorganic type ELD device has been widely used because of its capabilities of displaying full color and moving images, high brightness, and low driving voltage. Theflat panel devices such as LCD devices and ELD devices have a circuit unit and a display panel. The circuit unit converts RGB (red, green, and blue) data and control signals of the external driving system into pertinent electrical signals and the display panel shows images to users by using the electrical signals. The flat panel display receives image signals and horizontal and vertical synchronizing signals from a host. The received image signals are synchronized by the flat panel display according to the horizontal and vertical synchronizing signals and displayed thereby. The image signals generated from the host can have various types of modes according to video cards equipped in the host.
A liquid crystal display device is a flat-panel display device having characteristics of being thin and light-weight, and low power consumption. The liquid display devices provide richer and fuller colors and higher resolutions as compared with conventional display devices. As the result, the liquid display devices have been gaining its popularity among other display devices such as digital cameras, notebook computers, and flat panel television systems. A liquid crystal display device is composed essentially of two glass substrates that are separated to form a predetermined space into which a layer of liquid crystal is injected. A polymer thin film, called an alignment film, is disposed between the glass substrate and the liquid crystal layer, and the alignment film is processed for aligning the liquid crystal molecules. In the active matrix liquid crystal display device, a plurality of thin film transistors (TFTs) are formed near intersections between scanning lines and signal lines, and used as switching elements each for selectively driving a corresponding one of the pixel electrodes. Liquid crystal display panels generally operate by having a matrix of electrically controllable liquid crystals that are used to modulate reflected or emitted light. By turning on and off the liquid crystals of the matrix in a particular pattern, an image is rendered across liquid crystal matrix. The liquid crystal display device can display the images according to the changes of the optical characteristics of the liquid crystal cell.