inputdevices demo new.ppt
- 2. Block daigram of computer 2
- 3. 3 Input Devices • Keyboard. • Mouse • Light pen • Scanner • Touch screen • Microphone • Digital Camera • TrackBall • Bar code Reader • Magnetic Ink Card Reader • Optical Character Reader • Optical Mark Reader
- 4. 4 The Keyboard The most commonly used input device is the keyboard on which data is entered by manually keying in or typing certain keys. A keyboard typically has 104 or 108 keys.
- 5. keyboard 5
- 6. The keys on the keyboard are as follows − 1)Typing Keys These keys include the letter keys (A-Z) and digit keys (09) which generally give the same layout as that of typewriters. 2)Numeric Keypad It is used to enter the numeric data or cursor movement. Generally, it consists of a set of 17 keys that are laid out in the same configuration used by most adding machines and calculators. 3)Function Keys The twelve function keys are present on the keyboard which are arranged in a row at the top of the keyboard. Each function key has a unique meaning and is used for some specific purpose. 4)Control keys These keys provide cursor and screen control. It includes four directional arrow keys. Control keys also include Home, End, Insert, Delete, Page Up, Page Down, Control(Ctrl), Alternate(Alt), Escape(Esc). 5Special Purpose Keys Keyboard also contains some special purpose keys such as Enter, Shift, Caps Lock, Num Lock, Space bar, Tab, and Print Screen. 6
- 7. 7 Keyboard • The keyboard allows the computer user to enter words, numbers, punctuation, symbols, and special function commands into the computer’s memory.
- 8. 8 The Mouse Is a pointing device which is used to control the movement of a mouse pointer on the screen. It can perform functions like selecting menu commands, moving icons, resizing windows, staring programs and choosing options
- 9. 10 Touch screens • Often used for applications with occasional use, for example • Bank ATMs, • Input can be given through the computer screen. Users touch electronic buttons displayed on the screen or they may use light pen
- 10. 11 Light Pen • A light pen is a small ‘pen-shaped’ and, which contains light sensors • A light pen is similar to a mouse except that with a light pen. We can move the pointer and select objects on the display screen directly by pointing to the objects with the pen
- 11. 12 joystick The main use of a joystick is to play computer games by controlling the way that something moves on the screen.
- 12. 13 Microphones - Speech Recognition •Microphone is an input device, which takes voice as input. The voice communication is more error-prone than information through keyboard •Special software and a microphone are required
- 13. 14 Microphones - Speech Recognition
- 14. 15 Digital camera A digital camera can store many more pictures than an ordinary camera. Pictures taken using a digital camera are stored inside its memory and can be transferred to a computer by connecting the camera to it.
- 15. 16 Track Ball • Track Ball is a pointing device, is a mouse lying on its back. To move the pointer, you rotate the ball with your thumb. There are usually one to three buttons next to the ball, Which you use just like mouse buttons.
- 16. 17 Scanner A scanner can be used to input pictures and text into a computer..
- 17. 18 Bar codes •A bar code is a set of lines of different thicknesses that represent a number •Bar Code Readers are used to input data from bar codes. Most products in shops have bar codes on them •Bar code readers work by shining a beam of light on the lines that make up the bar code and detecting the amount of light that is reflected back
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- 19. Magnetic Ink Card Reader (MICR) • MICR input device is generally used in banks as there are large number of cheques to be processed every day. The bank's code number and cheque number are printed on the cheques with a special type of ink that contains particles of magnetic material that are machine readable 20
- 20. Optical Character Reader (OCR) • OCR is an input device used to read a printed text. OCR scans the text optically, character by character, converts them into a machine readable code, and stores the text on the system memory. 21
- 21. Optical Mark Reader (OMR) • OMR is a special type of optical scanner used to recognize the type of mark made by pen or pencil. It is used where one out of a few alternatives is to be selected and marked. It is specially used for checking the answer sheets of examinations having multiple choice questions. 22
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- 23. • Monitors, commonly called as Visual Display Unit (VDU), are the main output device of a computer. It forms images from tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the number of pixels. • There are two kinds of viewing screen used for monitors. • Cathode-Ray Tube (CRT) • Flat-Panel Display 25 Monitors
- 24. Cathode-Ray Tube (CRT) Monitor • The CRT display is made up of small picture elements called pixels. The smaller the pixels, the better the image clarity or resolution. • Most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically. • There are some disadvantages of CRT • Large in Size • High power consumption 26
- 25. Flat-Panel Display Monitor • The flat-panel display refers to a class of video devices that have reduced volume, weight and power requirement in comparison to the CRT. You can hang th • The flat-panel display is divided into two categories em on walls • LCD (Liquid-Crystal Device). • LED (Light-Emitting Diodes). 27
- 27. 29 Printers Printer is an output device, which is used to print information on paper. There are two types of printers − • Impact Printers • Non-Impact Printers
- 28. 30 Printers • Dot Matrix Printer • Dot matrix printing is a type of computer printing which uses a print head that moves back-and- forth, or in an up-and-down motion, on the page • Ink Jet Printer – least expensive, color, slower with a higher per page cost than laser printers • Laser Printer – More expensive, faster, lower per page cost than ink jet,
- 29. Impact printers 31 • Impact printers print the characters by striking them on the ribbon, which is then pressed on the paper. • Characteristics of Impact Printers are the following − • Very low consumable costs • Very noisy • Useful for bulk printing due to low cost • There is physical contact with the paper to produce an image These printers are of two types − • Character printers • Line printers
- 30. Character printers • Character printers are the printers which print one character at a time. These are further divided into two types: • Dot Matrix Printer(DMP) • Daisy Wheel 32
- 31. Dot Matrix Printers • In the market, one of the most popular printers is Dot Matrix Printer. These printers are popular because of their ease of printing and economical price. Each character printed is in the form of pattern of dots and head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or 9*9) which come out to form a character which is why it is called Dot Matrix Printer 33
- 32. Advantages • Inexpensive • Widely Used • Other language characters can be printed Disadvantages • Slow Speed • Poor Quality 34
- 33. Daisy Wheel • Head is lying on a wheel and pins corresponding to characters are like petals of Daisy (flower) which is why it is called Daisy Wheel Printer. These printers are generally used for word- processing in offices that require a few letters to be sent here and there with very nice quality. 35
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- 35. Line Printers • Line printers are the printers which print one line at a time. • These are of two types − • Drum Printer • Chain Printer 37
- 36. • Drum Printer • This printer is like a drum in shape hence it is called drum printer • Drum printers are fast in speed and can print 300 to 2000 lines per minute. Advantages Very high speed Disadvantages Very expensive Characters fonts cannot be changed 38
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- 39. Chain Printers • In this printer, a chain of character sets is used, hence it is called Chain Printer. A standard character set may have 48, 64, or 96 characters. • Advantages • Character fonts can easily be changed. • Different languages can be used with the same printer. • Disadvantages • Noisy 41
- 40. Non-impact Printers 42 • Non-impact printers print the characters without using the ribbon. These printers print a complete page at a time, thus they are also called as Page Printers. • These printers are of two types − • Laser Printers • Inkjet Printers Characteristics of Non-impact Printers • Faster than impact printers • They are not noisy • High quality • Supports many fonts and different character size
- 41. 43 Inkjet Laser Non impact printers • Inkjet printer, also called a bubble-jet, makes characters by inserting dots of ink onto paper • Letter-quality printouts • Cost of printer is inexpensive but ink is costly • These are non-impact page printers. They use laser lights to produce the dots needed to form the characters to be printed on a page. • Color printers available • Expensive initial costs but cheaper to operate per page
- 42. Inkjet printer • Advantages • High quality printing • More reliable • Disadvantages • Expensive as the cost per page is high • Slow as compared to laser printer 44
- 43. Laser Printer • Advantages • High quality printing • More reliable • Disadvantages • Expensive as the cost per page is high • Slow as compared to laser printer 45
- 44. 46 Plotter • It is a special kind of printer used to print large images like building plans or other such kind of images • It is used in engineering, drafting, map making.
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- 46. 48 Speakers • Speakers are another type of output device, which allows you to listion to voice like music, and conversation with people
- 47. Different types of speakers vary on the loudness of sound generated. Some of the speakers used are: • Ear phone • Head phone • Normal speaker • Woofer • Loud speaker 49
- 48. 50 Summary • Introduction • Input Devices – Keyboard,mouse,joystick,scanners,digital camera, bar code reader, touch Sreeen,Speech input device (microphone) • Output Devices – Monitor , Speaker, Printers ( different types),plotters
- 49. 51 THANK YOU