Electronic Displays Essay Example | Topics and Well Written Essays - 2000 words

Electronic Displays - Essay Example Electronic paper is a more recent electronic display technology (Facchetti and Marks 2010, p213). Cathode Ray Tube (CRT) CRT is a vacuum tube that uses a hot filament to produce electrostatic, magnetic fields, and thermo-electrons to â€Å"focus the electrons into a beam attracted to the high voltage anode which is the phosphor emit luminous radiation† (Maxim Integrated Products 2002, p1). Color CRTs generally utilize three electron sources or guns to target blue, green, and red phosphor prototypes to the screen. Electro-Luminescent Display (ELD) EL display is a solid-state display that uses phosphor to discharge light or a beam in the presence of an electric field. Phosphors utilized are generally green or yellow-orange (Maxim Integrated Products 2002, p1). Flip-Dot Display Each pixel is composed of a hinged disk. The disk is characterized by a reflective or a fluorescent (lit) on one side and a matt black on the other side (unlit). Various methods are used to flip the disk. One technique balances the disk around the electromagnetic soft iron framework. The winding is strengthened to attract the disk towards either of the sides. The remanent magnetism grasps the position and thus, only a small amount of energy (power pulse) is needed to flip the pixel. Incandescent Display (Light Bulb) A tungsten filament (which is coated) is run white hot in the vacuum. The filament generates both infrared (heat) and visible light. Liquid Crystal Display (LCD) LCD utilizes the liquid crystals properties in an electric field to direct light from the opposite polarized back and front display plates. The liquid crystal functions as a helical director to direct the light or beam through 90 degrees from one plate to the other plate. It is important to note that the liquid crystal acts as a director only when the driver gives the correct electric field (Maxim Integrated Products 2002, p2). Light Emitting Diode (LED) LED is a photon generating semiconductor, which generates l ight due to the effect of injection electroluminescence. The emitted light wavelength varies primarily because of the semiconductor material chosen and it is generally in infrared or a visible spectrum. Organic LEDs (OLED) Polymer LEDs (PLED) These forms of display utilize organic electroluminescent materials placed on flexible or a glass substrate. OLEDs are devices dependent on small organic polymer molecules and PLEDs are devices based on the large organic polymer molecules. Light is emitted through injection electroluminescence just like LEDs. The â€Å"choice of organic material sets the emission color OLED pixels are capacitive (tens to hundreds of pictofarads) leading to significant switching losses for large displays with high multiplex ratios† (Maxim Integrated Products 2002, p3). Glow Discharge (Plasma) Indicators (Nixie) Inert gas within a tube (the tube is composed of two electrodes under high voltage) is ionized permitting current to emerge around the cathode. Wh en the tube is driven from an alternating current (AC) source such as a neon indicator, the glow discharge emerges from both electrodes. Sophisticated displays utilize either multiple cathodes designed as complete numerals (each lit at a time) or segments (a character