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Dot-matrix
A dot matrix is a 2-dimensional patterned array, used to represent characters, symbols and images. Most types of modern technology use dot matrices for display of information, including mobile phones, televisions, and printers. The system is also used in textiles with sewing, knitting and weaving. An alternate form of information display using lines and curves is known as a vector display, was used with early computing devices such as air traffic control radar displays and pen-based plotters but is no longer used. Electronic vector displays were typically monochrome only, and either leave the interiors of closed vector shapes unfilled, or perform slow, time-consuming and often non-uniform shape-filling, as on pen-based plotters. In printers, the dots are usually the darkened areas of the paper. In displays, the dots may light up, as in an LED, CRT, or plasma display, or darken, as in an LCD. Usage in computers Although the output of modern computers is generally all in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Printer
In computing, a printer is a peripheral machine which makes a persistent representation of graphics or text, usually on paper. While most output is human-readable, bar code printers are an example of an expanded use for printers. Different types of printers include 3D printers, inkjet printers, laser printers, and thermal printers. History The first computer printer designed was a mechanically driven apparatus by Charles Babbage for his difference engine in the 19th century; however, his mechanical printer design was not built until 2000. The first patented printing mechanism for applying a marking medium to a recording medium or more particularly an electrostatic inking apparatus and a method for electrostatically depositing ink on controlled areas of a receiving medium, was in 1962 by C. R. Winston, Teletype Corporation, using continuous inkjet printing. The ink was a red stamp-pad ink manufactured by Phillips Process Company of Rochester, NY under the name Clear Prin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dot Matrix Printers
A dot matrix printer is an impact printer that prints using a fixed number of pins or wires. Typically the pins or wires are arranged in one or several vertical columns. The pins strike an ink-coated ribbon and force contact between the ribbon and the paper, so that each pin makes a small dot on the paper. The combination of these dots forms a dot matrix image. They were also known as serial dot matrix printers. While inkjet and laser printers technically exhibit dot matrix printing, they work differently than impact "dot matrix printers" and can deposit ink or toner at higher dot resolutions more quickly, with less inherent noise. The impact printer has the ability to make copies using multi-part forms, unlike an inkjet or laser printer. History In the 1970s and 1980s, dot matrix impact printers were generally considered the best combination of cost and versatility, and until the 1990s were by far the most common form of printer used with personal and home computers. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light-emitting Diode
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device. Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red. Early LEDs were often used as indicator lamps, replacing small incandescent bulbs, and in seven-segment displays. Later developments produced LEDs available in visible, ultraviolet (UV) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daisy Wheel
Daisy wheel printing is an impact printing technology invented in 1970 by Andrew Gabor at Diablo Data Systems. It uses interchangeable pre-formed type elements, each with typically 96 glyphs, to generate high-quality output comparable to premium typewriters such as the IBM Selectric, but two to three times faster. Daisy wheel printing was used in electronic typewriters, word processors and computers from 1972. The daisy wheel is so named because of its resemblance to the daisy flower. By 1980 daisy wheel printers had become the dominant technology for high-quality text printing. Dot-matrix impact, thermal, or line printers were used where higher speed or image printing were required and poor print quality was acceptable. Both technologies were rapidly superseded for most purposes when dot-based printers—in particular laser printers—that could print any characters or graphics, rather than being restricted to a limited character set, became able to produce output ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Text Mode
Text mode is a computer display mode in which content is internally represented on a computer screen in terms of characters rather than individual pixels. Typically, the screen consists of a uniform rectangular grid of ''character cells'', each of which contains one of the characters of a character set; at the same time, contrasted to all points addressable (APA) mode or other kinds of computer graphics modes. Text mode applications communicate with the user by using command-line interfaces and text user interfaces. Many character sets used in text mode applications also contain a limited set of predefined semi-graphical characters usable for drawing boxes and other rudimentary graphics, which can be used to highlight the content or to simulate widget or control interface objects found in GUI programs. A typical example is the IBM code page 437 character set. An important characteristic of text mode programs is that they assume monospace fonts, where every character has the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raster Image
upright=1, The Smiley, smiley face in the top left corner is a raster image. When enlarged, individual pixels appear as squares. Enlarging further, each pixel can be analyzed, with their colors constructed through combination of the values for red, green and blue. In computer graphics and digital photography, a raster graphic represents a two-dimensional picture as a rectangular matrix or grid of square pixels, viewable via a computer display, paper, or other display medium. A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel. Raster images are stored in image files with varying dissemination, production, generation, and acquisition formats. The printing and prepress industries know raster graphics as contones (from ''continuous tones''). In contrast, line art is usually implemented as vector graphics in digital systems. Many raster manipulations map directly onto the mathematical formalisms of linear alg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raster Image Processor
A raster image processor (RIP) is a component used in a printing system which produces a raster image also known as a bitmap. Such a bitmap is used by a later stage of the printing system to produce the printed output. The input may be a page description in a high-level page description language such as PostScript, PDF, or XPS. The input can also be or include bitmaps of higher or lower resolution than the output device, which the RIP resizes using an image scaling algorithm. Originally a RIP was a rack of electronic hardware which received the page description via some interface (e.g. RS-232) and generated a "hardware bitmap output" which was used to enable or disable each pixel on a real-time output device such as an optical film recorder, computer to film, or computer to plate. A RIP can be implemented as a software module on a general-purpose computer, or as a firmware program executed on a microprocessor inside a printer. For high-end typesetting, standalone hardware R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embossing (manufacturing)
Sheet metal embossing is a stamping process for producing raised or sunken designs or relief in sheet metal. This process can be made by means of matched male and female roller dies, or by passing sheet or a strip of metal between rolls of the desired pattern. It is often combined with foil stamping to create a shiny, 3D effect. Process The metal sheet embossing operation is commonly accomplished with a combination of heat and pressure on the sheet metal, depending on what type of embossing is required. Theoretically, with any of these procedures, the metal thickness is changed in its composition. Metal sheet is drawn through the male and female roller dies, producing a pattern or design on the metal sheet. Depending on the roller dies used, different patterns can be produced on the metal sheet. The pressure and a combination of heat actually "irons" while raising the level of the image higher than the substrate to make it smooth. The term "impressing" refers to an image ''l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Line Printer
A line printer prints one entire line of text before advancing to another line. Most early line printers were impact printers. Line printers are mostly associated with unit record equipment and the early days of digital computing, but the technology is still in use. Print speeds of 600 lines per minute (approximately 10 pages per minute) were achieved in the 1950s, later increasing to as much as 1200 lpm. Line printers print a complete line at a time and have speeds in the range of 150 to 2500 lines per minute. The types of line printers are drum printers, band-printers, and chain printers. Other non-impact technologies have also been used, as thermal line printers were popular in the 1970s and 1980s, and some inkjet and laser printers produce output a line or a page at a time. Designs Many impact printers, such as the daisywheel printer and dot matrix printer, used a print head that printed a character then moved on until an entire line was printed. Line printers we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typewriter
A typewriter is a mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of keys, and each one causes a different single character to be produced on paper by striking an inked ribbon selectively against the paper with a type element. At the end of the nineteenth century, the term 'typewriter' was also applied to a ''person'' who used such a device. The first commercial typewriters were introduced in 1874, but did not become common in offices until after the mid-1880s. The typewriter quickly became an indispensable tool for practically all writing other than personal handwritten correspondence. It was widely used by professional writers, in offices, business correspondence in private homes, and by students preparing written assignments. Typewriters were a standard fixture in most offices up to the 1980s. Thereafter, they began to be largely supplanted by personal computers running word processing software. Nevertheless, typewr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonless Copy
Carbonless copy paper (CCP), non-carbon copy paper, or NCR paper (No Carbon Required, taken from the initials of its creator, National Cash Register) is a type of coated paper designed to transfer information written on the front onto sheets beneath. It was developed by chemists Lowell Schleicher and Barry Green, as an alternative to carbon paper and is sometimes misidentified as such. Carbonless copying provides an alternative to the use of carbon copying. Carbonless copy paper has micro-encapsulated dye or ink on the back side of the top sheet, and a clay coating on the front side of the bottom sheet. When pressure is applied (from writing or impact printing), the dye capsules rupture and react with the clay to duplicate the markings made to the top sheet. Intermediary sheets, with clay on the front and dye capsules on the back, can be used to create multiple copies; this may be referred to as multipart stationery. Operation Carbonless copy paper consists of sheets of paper th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
