|
Addressing Scheme
{{unreferenced, date=June 2009, bot=yes There are three different addressing schemes for display devices: ''direct'', ''matrix'', and ''raster''. The purpose of each scheme is to set (or maintain) the state of a pixel to either black/white or, more commonly, a grayscale level. Direct addressing A direct addressed display runs individual control signals to each pixel. This allows the state, whether on/off or grayscale, to be set and maintained on each pixel. For a screen size of ''m''×''n'' pixels, this scheme would require ''m''×''n'' control signals. This is generally considered to be an inefficient use of I/O and physical space. Direct addressing mode means that the value for a given instruction in assembly programming is pointed to by a given value. This means the value is variable, based on what is stored in memory at a given address Matrix addressing A matrix addressed display runs control signals only to the rows and columns of the display. (See also: matrix) For a sc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Display Device
A display device is an output device for presentation of information in visual or tactile form (the latter used for example in tactile electronic displays for blind people). When the input information that is supplied has an electrical signal the display is called an ''electronic display''. Common applications for ''electronic visual displays'' are television sets or computer monitors. Types of electronic displays In use These are the technologies used to create the various displays in use today. * Liquid crystal display (LCD) ** Light-emitting diode (LED) backlit LCD ** Thin-film transistor (TFT) LCD ** Quantum dot (QLED) display * Light-emitting diode (LED) display ** OLED display ** AMOLED display ** Super AMOLED display Segment displays Some displays can show only digits or alphanumeric characters. They are called segment displays, because they are composed of several segments that switch on and off to give appearance of desired glyph. The segments are us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pixel
In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device. In most digital display devices, pixels are the smallest element that can be manipulated through software. Each pixel is a sample of an original image; more samples typically provide more accurate representations of the original. The intensity of each pixel is variable. In color imaging systems, a color is typically represented by three or four component intensities such as red, green, and blue, or cyan, magenta, yellow, and black. In some contexts (such as descriptions of camera sensors), ''pixel'' refers to a single scalar element of a multi-component representation (called a ''photosite'' in the camera sensor context, although ''sensel'' is sometimes used), while in yet other contexts (like MRI) it may refer to a set of component intensities for a spatial position. Etymology The w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grayscale
In digital photography, computer-generated imagery, and colorimetry, a grayscale image is one in which the value of each pixel is a single sample representing only an ''amount'' of light; that is, it carries only intensity information. Grayscale images, a kind of black-and-white or gray monochrome, are composed exclusively of shades of gray. The contrast ranges from black at the weakest intensity to white at the strongest. Grayscale images are distinct from one-bit bi-tonal black-and-white images, which, in the context of computer imaging, are images with only two colors: black and white (also called ''bilevel'' or '' binary images''). Grayscale images have many shades of gray in between. Grayscale images can be the result of measuring the intensity of light at each pixel according to a particular weighted combination of frequencies (or wavelengths), and in such cases they are monochromatic proper when only a single frequency (in practice, a narrow band of frequencies) is ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matrix (mathematics)
In mathematics, a matrix (plural matrices) is a rectangular array or table of numbers, symbols, or expressions, arranged in rows and columns, which is used to represent a mathematical object or a property of such an object. For example, \begin1 & 9 & -13 \\20 & 5 & -6 \end is a matrix with two rows and three columns. This is often referred to as a "two by three matrix", a "-matrix", or a matrix of dimension . Without further specifications, matrices represent linear maps, and allow explicit computations in linear algebra. Therefore, the study of matrices is a large part of linear algebra, and most properties and operations of abstract linear algebra can be expressed in terms of matrices. For example, matrix multiplication represents composition of linear maps. Not all matrices are related to linear algebra. This is, in particular, the case in graph theory, of incidence matrices, and adjacency matrices. ''This article focuses on matrices related to linear algebra, and, unle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Matrix Addressing
Active may refer to: Music * ''Active'' (album), a 1992 album by Casiopea * Active Records, a record label Ships * ''Active'' (ship), several commercial ships by that name * HMS ''Active'', the name of various ships of the British Royal Navy * USCS ''Active'', a US Coast Survey ship in commission from 1852 to 1861 * USCGC ''Active'', the name of various ships of the US Coast Guard * USRC ''Active'', the name of various ships of the US Revenue Cutter Service * USS ''Active'', the name of various ships of the US Navy Computers and electronics * Active Enterprises, a defunct video game developer * Sky Active, the brand name for interactive features on Sky Digital available in the UK and Ireland * Active (software), software used for open publishing by Indymedia; see Independent Media Center Sciences * Thermodynamic activity, measure of an effective concentration of a species in a mixture. * Activation, in chemistry the process whereby something is prepared for a su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passive Matrix Addressing
Passive matrix addressing is an addressing scheme used in early LCDs. This is a matrix addressing scheme meaning that only ''m'' + ''n'' control signals are required to address an ''m'' × ''n'' display. A pixel in a passive matrix must maintain its state without active driving circuitry until it can be refreshed again. The signal is divided into a row or ''select signal'' and a column or ''video signal''. The select voltage determines the row that is being addressed and all ''n'' pixels on a row are addressed simultaneously. When pixels on a row are being addressed, a ''Vsel'' potential is applied, and all other rows are unselected with a ''Vunsel'' potential. The video signal or column potential is then applied with a potential for each ''m'' columns individually. An on-switched (lit) pixel corresponds to a ''Von'', an off-switched (unlit) corresponds to a ''Voff'' potential. The potential across pixel at selected row ''i'' and column ''j'' is :V_ = V_ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathode Ray Tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms ( oscilloscope), pictures (television set, computer monitor), radar targets, or other phenomena. A CRT on a television set is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer. The term ''cathode ray'' was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons. In CRT television sets and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster. In color devices, an image is produced by controlling the intensity of each of three electron beams, one for each additive primary color (red, green, and bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphor
A phosphor is a substance that exhibits the phenomenon of luminescence; it emits light when exposed to some type of radiant energy. The term is used both for fluorescent or phosphorescent substances which glow on exposure to ultraviolet or visible light, and cathodoluminescent substances which glow when struck by an electron beam (cathode rays) in a cathode-ray tube. When a phosphor is exposed to radiation, the orbital electrons in its molecules are excited to a higher energy level; when they return to their former level they emit the energy as light of a certain color. Phosphors can be classified into two categories: fluorescent substances which emit the energy immediately and stop glowing when the exciting radiation is turned off, and phosphorescent substances which emit the energy after a delay, so they keep glowing after the radiation is turned off, decaying in brightness over a period of milliseconds to days. Fluorescent materials are used in applications in which the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
