Components Of Computer, Output Devices-Computer Fundamentals-Lecture Notes, Study notes of Computer Fundamentals

Download Components Of Computer, Output Devices-Computer Fundamentals-Lecture Notes and more Study notes Computer Fundamentals in PDF only on Docsity! Chapter No 3:  Components of Computer‐Output Devices  19    Chapter No 3 COMPONENTS OF COMPUTER OUTPUT DEVICES WHAT IS OUTPUT? An output is the data that has been processed in that form which is useful by user or machine for future processing. Output can be in two forms Soft Copy and Hard Copy. (Describe further) WHAT ARE OUTPUT DEVICES? Any hardware component used to show results after processing to any user and it use to send the results of processing to the user. Output can be text, Audio, Video & graphics. Examples  Monitor  Printer  Plotter  Projectors  Speakers  Headphone etc REVISION: Components of computer: Input, Output, CPU Input: Any data which is entered to computer for processing. Input Devices: The Hardware components to do input. Key Board, Mouse, Track ball, touch pad, speakers etc are input devices There are many other biometric devices used to do input like voice recognition and retina scanners. docsity.com Chapter No 3: Components of Computer-Output Devices OUTPUT DEVICES MONITORIDISPLAY PRIECTORS SPEAKERS DEVICES HEAD PHONE: PLOTTERS I HONOCHROME MOMITOR COLOR MONITOR FRINTERS | CRT Ton] [SASPLAGNA] [TOUCHSCREEN WOUMIPECT hworiTo| hucwirors| | wowmers | | wonToRS IMPACT PREVTERS PRINTERS I perma | [une] [caer | [aMmeT || LASER | [THERUAL | [PHOT | [noBLe panmer | panmens| | wee. | [ranmes |Jranmes | | primer | | primer | PRITER docsity.com 20 Chapter No 3:  Components of Computer‐Output Devices  23    measured in hertz .it is also an important feature for better quality of display. , this is the number of times the image is refreshed every second. A low refresh rate makes the image appear to flicker. You need a refresh rate of at least 72 Hz (72 times a second) to avoid the appearance of flicker. 1.2.1) CRT MONITORS The cathode ray tube (CRT) type monitors and makes use of the same technology as a television screen. A beam of electronics is fired from an electronic gun at the back of the tube. This strikes the front of the tube which is covered in a phosphorescent material which glows when struck by electrons. Between the electron gun and the screen the beam is modulated by a signal to produce the image you see on the screen. docsity.com Chapter No 3:  Components of Computer‐Output Devices  24    1.2.2) LCD MONITORS The LCD monitors bring lots of advantages when compared to the CRT ones. The first advantage which is also the most obvious one is the fact that the LCD monitors are smaller and have a smaller weight than the CRT monitors. The LCD monitors can be placed on the table and they use far less space than the CRT monitors. This is a great advantage. The picture quality of the LCD monitors will be increased as well which means that the movies will be displayed in a better quality and the games will have better colors, and so on. In most of the cases the LCD monitors will have certain features which provide additional functionality. Some of the LCD monitors have USB hubs, HDMI input, TV tuner, and so on. The TV tuner is very important because you can use the computer for watching TV. The aspect ratio of the monitors has changed. The resolution will be highly influenced by the monitor size. The larger the size of the monitor is the larger resolutions it will have. If you buy the biggest monitor that you can buy because the experience of watching movies or playing games on it will be much more enjoyable. This was my info on the LCD computer monitors. 1.2.3) GAS PLASMAMONITORS A gas-plasma display works by sandwiching neon gas between two plates. Each plate is coated with a conductive print. The print on one plate contains vertical conductive lines and the other plate has horizontal lines. Together, the two plates form a grid. When electric current is passed through a horizontal and vertical line, the gas at the intersection glows, creating a point of light, or pixel. You can think of a gas-plasma display as a collection of very small neon bulbs. Images on gas-plasma displays generally appear as orange objects on top of a black background. docsity.com Chapter No 3:  Components of Computer‐Output Devices  25    1.2.4) TOUCH SCREEN MONITORS These monitors use touching of the screen as an input method. Items can be selected or moved with a finger, and finger gestures may be used to convey commands. The screen will need frequent cleaning due to image degradation from fingerprints. 2) PRINTERS The second most common form of computer output is printed documents. Although a computer can operate perfectly without a printer, it is certainly helpful to the user to have one. People often prefer to get printouts of the work they have done rather than to look at it on the screen it is considered a form of hard copy. Types: Printer has majorly two types.  Impact printers  Non impact printers 2.1) IMPACT PRINTERS Impact printers produce output by striking a ribbon with a hammer. When the ribbon is hit a mark is made on the paper behind it. If carbon paper is put into the printer then an impact printer can print more than one copy of a document at a time. This feature is often used by companies when they print invoices, bills etc. Because of the hammering action impact printers are noisy when they are printing. docsity.com Chapter No 3:  Components of Computer‐Output Devices  28    5,000 and color ones from about 10,000. They are slower than laser printers (3ppm) and cost slightly more to run. 2.2.2) LASER PRINTERSS Laser printers are called Page Printers because they print a whole page at a time. A laser beam is used to draw the image to be printed onto a light sensitive Drum. After the image has been drawn on the drum a fine powder ink called Toner is put onto it. The toner only sticks where the laser has drawn the image. The paper then passes over the drum and the toner is transferred onto the paper. Laser printers produce very high quality output, are very quiet and very fast. Typical home laser printers can print 8 pages per minute (ppm). Some industrial versions print over 40ppm and can print on both sides of a piece of paper at the same time. The main disadvantage of this type of printer is the high cost. Small laser printers cost from Rs 3,000 to buy and are more usually about Rs 8,000. Color laser printers cost Rs 30,000+. Running costs are higher than impact printers but lower than most ink jet printers. 2.2.3) THERMAL PRINTERS Thermal printers are no longer used as printers for PCs. They are however still used in some computer control systems, tills and in many fax machines. These printers print on special heat sensitive paper which is expensive. The image is produced from small dots which are made on the paper by heating it up. The quality is reasonable and graphics can be printed. docsity.com Chapter No 3:  Components of Computer‐Output Devices  29    2.2.4) PHOTO PRINTERS A printer specialized for smaller prints such as 4x6" and 5x7". When first introduced in the mid-1990s, photo printers used dye sublimation for high quality printing because inkjet printing was not quite up to par. Since then, inkjet technology has greatly improved, and most photo printers are inkjets. Epson, Canon and HP are major players in this market 2.2.5) MOBILE PRINTERS A monitor is portable and we can take it any where we want. Mobile printers are making it easier and faster for us to free our trapped images from their digital prisons -- all without using a drop of ink. Without ink, it can be dramatically smaller than their predecessors, making them more convenient and even portable. It is said to be "mobile" because it receive wireless signals to print. However, with inkless printing technology, printers can be mobile in a more radical way -- you can carry it around in a pocket or a purse, just like a cell phone 3) PLOTTERS  A plotter, like a printer, produces hard-copy output. Plotters, which produce high-quality color graphics, are usually categorized by whether they use pens or electrostatic charges to create images. A continuous-curve plotter is used to draw maps from stored data. Computer- generated maps can be retrieved and plotted or used to show changes over time. Plotters are generally more expensive than printers, ranging from about 100,000 to $750,000 (or even more). docsity.com Chapter No 3:  Components of Computer‐Output Devices  30    4) SPEAKERS/ HEADPHONE Speakers and headset is used to get audio output. A system's speaker is the component that takes the electronic signal stored on things like CDs, tapes and DVDs and turns it back into actual sound that we can hear. In any sound system, ultimate quality depends on the speakers. The best recording, encoded on the most advanced storage device and played by a top-of-the-line deck and amplifier, will sound awful if the system is hooked up to poor speakers. 5) MULTIMEDIA/PROJECTORS A Digital Projector/Multimedia is an electo-optical machine which converts image data from a computer or video source to a bright image which is then imaged on a distant wall or screen using a lens system. The cost of a device is not only determined by its resolution, but also by its brightness. The projector serves the following purposes:  Visualization of data stored in a computer for presentations  Demonstration of program products for a large number of prospective customers  The projector replaces the white board as well as written documents.  Watching moving images from a video tape player or digital video disk player.  Digital projectors may also be built into cabinets which use a rear projection screen to form a single unified display device, now popular for "home theater" applications. docsity.com