SECTION 3 Input And Output Devices. Sophia Pratzioti

Transcription

1 SECTION 3 Input And Output Devices Sophia Pratzioti

2 Sophia Pratzioti 2 Input and Output Devices By the end of this section students should be able to: Identify input devices and their uses. Describe direct data entry and associated devices Identify the advantages and disadvantages of any of the above devices in comparison with the others. Identify output devices and their uses, Describe the advantages and disadvantages of any of the above devices.

3 Sophia Pratzioti 3 PART 2.1 MANUAL INPUT DEVICES

4 Sophia Pratzioti 4 Input Devices (What are they?) Definition: Are those devices that allow data to be entered into a computer. A mouse is an example of a commonly used input device A keyboards is another example of a commonly used input device.

5 Sophia Pratzioti 5 Overview of Input Devices Input devices are part of the 4 main hardware components of a computer system: Input Devices - these get data into the computer Processor - this does something with the data to make it useful information Output Devices - these show the results of processing Storage Devices - holds the data in the system

6 Sophia Pratzioti 6 Overview of Input Devices The image below shows where input devices fit into a computer system: This diagram shows where input devices fit into a computer system.

7 Sophia Pratzioti 7 Manual Vs. Direct Input Devices There are two different types of input devices: 1) Manual Input Devices - Data is input into the computer by hand (people have to do most of the work) 2) Direct Input Devices - Data is input into the computer directly by a machine/device (there is minimal input by people)

8 Sophia Pratzioti 8 Manual Input Devices (data entered by hand) Examples of Manual Input Devices: Remote Control Keyboard Numeric Keypad Mouse Graphic Tablet Joystick Touchscreen Scanner Light Pen Digital Camera Web Camera Microphone

9 Sophia Pratzioti 9 Manual Input Devices (data entered by hand) REMEMBER! Manual input devices require humans to do most of the work needed to get data into the system. For Example: If you are using a keyboard to input instructions into the computer, you have press the keys yourself. It is a manual job not automatic.

10 Sophia Pratzioti Keyboard Keyboards are one of the most commonly used manual input devices Keyboards are used to input the following into the computer: Text Numbers Instructions Most keyboard use a QWERTY key layout. The name QWERTY comes from the first five lettered keys on the top row of the keyboard -Q-W-E-R-T-Y. The first five lettered keys of a keyboard spell out QWERTY.

11 Sophia Pratzioti Keyboard (Ergonomic) Special keyboards called Ergonomic Keyboards have been developed to help reduce health problems (such as Repetitive Strain Injury) linked with typing. Ergonomic keyboards have a more natural shape to them with reduces stress on the wrist and hands. Ergonomic keyboards also come with a built-inhand-rest which further helps prevent health issues such as RSI Ergonomic Keyboards have a natural shape and built-in hand-rest

12 Uses of Keyboard Keyboards are used to input data into applications. For Example Entering text into word processing applications like MS Word Entering numbers into spreadsheet applications like MS Excel Keyboards can be also be used to enter commands into the computer. For Example Keyboard shortcuts: CTRL + P to print CTRL + S to save CTRL + C to copy CTRL + V to paste PRT SC to take a screen shot of your work Sophia Pratzioti 12 Inputting data into a computer using a keyboard Command Line operating Systems require a keyboard in order to be able to use the computer at all!

13 Sophia Pratzioti 13 Advantages and Disadvantages of using a Keyboard

14 Sophia Pratzioti Numeric Keypads Numeric Keypads are used for entering numbers into a computer system ( Numeric means number ) Some numeric keypads also allow you to enter a simple text and symbols. Bank ATM s use numeric keypads to let us enter PIN numbers and withdrawal amounts Mobile phones use numeric keypads to allow us enter phone numbers

15 Sophia Pratzioti Uses of Numeric Keypads There are many day to day uses of numeric keypads. Here are some of them:

16 2. Advantages and Disadvantages of Numeric Keypads Sophia Pratzioti 16 There are many day to day uses of numeric keypads. Here are some of them:

17 Sophia Pratzioti Pointing Devices (mouse, touchpad, trackerball) Pointing devices are pieces of hardware that are used to control a pointer (cursor) on a screen. Pointing devices are frequently used with Graphical User Interface (GUI) operating systems where pointers are used to input commands by selecting icons.

18 Sophia Pratzioti 18 Pointing Devices (mouse, touchpad, trackerball) There are three types of pointing devices and these are listed below: Mouse Touchpad Trackerball Mice are one of the devices that allow us to control a screen pointer Trackerball also allow us to control a screen pointer

19 Sophia Pratzioti 19 Information about the Mouse There are two different types of mice a ball mouse and an optical mouse. Ball Mouse Uses a ball under the mouse to detect movement. Optical Mouse Uses reflected light to detect movement. The ball (in a ball mouse) and the reflected light (in an optical mouse) allow us to direct and control an on-screen pointer. A ball mouse uses a ball to detect movement. These are prone to clogging which can affect accuracy. An optical mouse uses light to detect movement. These are more accurate than ball mice and are better for editing images.

20 Sophia Pratzioti 20 Information about the Mouse Mice have two buttons and a scroll wheel. These provide users with different functions: Left button is used to select icons and click options Right button is used to call up a drop-down menu of options Scroll wheel is used to move up and down through a document Mice use two buttons and a scroll wheel to allow us to activate different functions.

21 Sophia Pratzioti 21 Information about the Mouse Cordless mice work in the same way as a regular mice but the don not need a wire plugged into the computer. They are powered by batteries instead of the computer. Cordless mice are an example of a wireless device.

22 Sophia Pratzioti 22 Uses of Mouse Common uses of mouse include:

23 Sophia Pratzioti 23 Advantages and Disadvantages of Mice

24 Sophia Pratzioti 24 Information about Touchpad Used as a replacement to a mouse in many laptops. Users lightly brush their finger over the touchpad in order to control a pointer. Touchpads have two buttons which have the same purpose as mouse buttons. Left Button Used to select icons and activate options. Right Button Used to call up a dropdown list of menu options.

25 Sophia Pratzioti 25 Uses of Touchpad Touchpads have the same uses as mice:

26 Sophia Pratzioti 26 Advantages and Disadvantages of Touchpads

27 Sophia Pratzioti 27 Information about Trackerball Trackerballs are similar to mice but the ball is on the top of the device instead of the bottom. Screen pointers are controlled by rotating the large ball with your hand. The buttons on trackerballs perform the same functions as those on mice and touchpads

28 Sophia Pratzioti 28 Uses of Trackerball s Trackerball s have the same functions as mice They are however, much more comfortable to use the mice. This means that people with painful hand and wrist problems (like RSI) can use trackerball.

29 Sophia Pratzioti 29 Uses of Trackerball s Why they are more comfortable? Trackerball s re more comfortable than mice because there is less wrist movement required. They are more ergonomic. Some arcade gaming machines use trackerball s to control games characters on screen. Because trackerball s are so durable (tough) they can deal with the wear and tear of gamers using them.

30 Sophia Pratzioti 30 Advantages and Disadvantages of Trackerball s

31 Sophia Pratzioti Remote Control Remote controls are used to control other devices using infra-red signals. Buttons on the remote control can be used to perform functions such as: Changing the channel on a T.V Increasing/Decreasing the volume on a music player Selecting a different chapter on a DVD player

32 Sophia Pratzioti 32 Uses of Remote Controls Home entertainment systems use remote controls. Example: Hi-Fi systems (music centers) DVD / Blu-Ray Players Satellite systems Some overhead projectors Industry uses remote controls to operate machinery that might to too dangerous to get near to. Examples include: Cranes with heavy loads Activating explosive in demolition Operating robot arms in hazardous chemical planets

33 Sophia Pratzioti 33 Advantages and Disadvantages Remote Controls

34 Sophia Pratzioti Joysticks Joysticks have similar functions to that of mice and trackerballs, to control a pointer on a screen. There are two main parts to a joystick: Handle / Stick Allows us to move a pointer in the direction we want. Buttons - Allow us to select option or click stuff Joysticks are also popular devices for gaming. The handle allows gamers to control on-screen characters and the buttons are used for things like firing weapons.

35 Sophia Pratzioti 35 Uses of Joysticks They can control characters or objects in video games. Can control industrial machinery (cranes for example) They are used in simulators. For example flight simulators use joysticks in order for trainee pilots to control the simulated plane.

36 Sophia Pratzioti 36 Advantages and Disadvantages of Joysticks

37 Sophia Pratzioti Touch Screens Touch screens allow users to input commands into a computer by pressing or touching buttons/icons on the screen. Giving users this ability to touch or press icons on the screen removes the need to use a mouse. Touch screens are more suitable for use with a limited amount of options.

38 Uses of Touch Screens Sophia Pratzioti 38

39 Advantages and Disadvantages of Touch Screens Sophia Pratzioti 39

40 7. Scanners Sophia Pratzioti 40 Scanners are used to enter information on paper (hard copies) into a computer. Scanners can convert hard copies (printed documents, photographs etc) into digital data. This digital data can then be stored and manipulated on your computer. Scanners reflect light off the hard copy in order to capture an analogue image of the document. The scanner then converts the received analogue data into a digital format. Once the hard copy has been converted to digital data, it can be stored on a computer and manipulated using Graphics Editing Software (such as Photoshop).

41 Sophia Pratzioti 41 Scanners Used to convert hard copy documents into digital form to allow it to be stored on a computer. Advantages Very fast to enter hard copies into the computer (compared to retyping with a keyboard) Very easy to scan and store documents and images into the computer Disadvantages Scanned images are usually less quality than the original document Scanned documents can take up a lot of disk space Old photo's that may damaged can be scanned into the computer then repaired using Graphics Editing Software

42 Scanners Sophia Pratzioti 42

43 Sophia Pratzioti Graphics Tablet They are used by artists and designers to easily create and store digital graphics in a computer Draw with a special pen called stylus Advantages Much easier to draw images using a pen than a mouse Very accurate drawings can be produced Disadvantages Very expensive when compared to a mouse Not useful for some input needs Useful in countries where drawings and symbols are used instead of text

44 Sophia Pratzioti Light Pen A light pen is a device used as a pointing device or to write on the screen of a computer. Light pens are rarely used today since graphics tablets and high-quality touch screens provide similar functionality. Advantages More accurate than touch screens They are very small and so can be used where there is no space for a mouse or graphics tablet Disadvantages Not as accurate as a graphics tablet Can be quite uncomfortable to use as you have to hold your hand raise up to the computer Can only be used with CRT screens

45 Sophia Pratzioti Microphone They are used to input analogue sounds into a digital computer Uses: narration, speaking over the Internet, videoconferencing Advantages Faster to read in text than to type it in using keyboard Means that word processors can be used by people who cannot use their hands Very cheap to buy Disadvantages Sound files can take up a lot of computer storage space Background noise can prevent the correct use of recognition system Speaking words into a word processor is not as accurate as typing. A lot of mistakes.

46 Sophia Pratzioti Digital Cameras A device that captures digital photographs. The image is captured in a digital form that can be sent directly to a computer. Advantages No film is needed and there are no film developing costs Unwanted images can be deleted easily Disadvantages Camera users needs to have computer skills to be able to transfer and print digital photographs Not all digital cameras produce images as high-quality as tradition cameras Digital images can be improved and edited easily Digital images can easily transferred

47 Sophia Pratzioti Web Cameras They are similar to digital cameras in their function but they are directly connected to a computer and do not have memory storage They can capture both digital images and video Uses: face to face conversations, videoconferencing, etc. Advantages Able to interact with people across long distances Parents can keep an eye on their children from a different location Disadvantages The image / video quality can sometimes be poor Are usually in a fixed position and so cannot be easily moved around They do not have their own storage and so must be permanently fixed to the computing device

48 13. Sensors Sophia Pratzioti 48 A device which automatically inputs data into a computer system, where the data is constantly changing and can be measured Used to detect data in the surrounding environments that constantly changes This information is physical and analogue Computers don t understand analogue data and therefore it need to be converted to digital. The computer can then read the data A special device called Analogue to Digital Converter (ADC)

49 Sensors Sophia Pratzioti 49

50 Uses of Sensors Temperature Sensor Automatic washing machines Automatic cookers Air conditioning controllers Central heating controllers Computer-controlled greenhouses Monitoring and recording scientific experiments Environmental monitoring and recording Pressure Burglar alarms Automatic washing machines Robotics Production-line control Sophia Pratzioti 50 Monitoring and recording scientific experiments Environmental monitoring and recording Light Computer-controlled greenhouses Burglar alarms Robotics Production-line control Monitoring and recording scientific experiments Environmental monitoring and recording

51 Sophia Pratzioti 51 Sensors Advantages Readings taken using sensors are more accurate than those taken by a human Sensors can monitor information constantly (they don t get tired like humans can) Sensors can respond to information immediately Disadvantages Faulty sensors can give incorrect results No need for humans to operate sensors

52 Sophia Pratzioti 52 PART 2.2 DIRECT INPUT DEVICES

53 Direct Input Devices (no/little human interaction needed) Examples of Direct Input Devices: Sophia Pratzioti 53 Radio Frequency ID Reader (RFIR) Magnetic Stripe Reader (MSR) Chip and PIN Reader Bar Code Reader Optical Mark Reader (OMR) Optical Character Reader (OCR) Magnetic Ink Character Recognition(MICR)

54 Sophia Pratzioti 54 Direct Input Devices (no/little human interaction needed) REMEMBER! Direct input devices do not require much human interaction to get their data into the system. For Example: All human has to do to use a Barcode Reader is point the reader at the barcode and pull the trigger. The reader will do the rest.

55 1. Magnetic Stripe Reader Reads information from magnetic stripes found on Bank Cards, Membership Cards and Hotel Door Cards The strip holds information such as: Bank account number Name of card holder Expiry date, etc. Uses: ATM s EFTPOS Electronic Funds Transfer Point Sophia Pratzioti 55

56 Magnetic Stripe Reader Sophia Pratzioti 56

57 Sophia Pratzioti 57 Magnetic Stripe Reader vs. Chip and Pin Reader Advantages Disadvantages Entering data is very fast, you just swipe the card through the machine The magnetic stripe on cards can only hold small amount of data No possibly of data entry errors as there is no typing The stripes on cards are not affected by water and are not easily damages Data held on the card cannot be read by eye so bank details are safe The cards need to be in contact with the reader in order to be used If the stripe does get damaged then the data is lost Magnetic stripes on cards are easily duplicated

58 Sophia Pratzioti Chip and Pin Reader These allow people to pay for goods and services electronically at EFTPOS terminals It works by inserting a bank card/credit card into a slot and then entering a PIN If the correct PIN is entered, the cost of goods will be taken from the card holder s bank and transferred to the companies Use: Supermarkets Restaurants Cafes Buying petrol Etc.

59 Chip and Pin Reader Advantages Sophia Pratzioti 59 Disadvantages More secure than magnetic stripe readers as the user needs to know the correct PIN Information contained on the chip is harder to copy than it is to copy magnetic stipe readers Chips can hold more data than magnetic stripes can Chip and Pin Readers are portable so they can be brought to you It is possible to forget your PIN which means you cannot make payments with your card People can look over your shoulder as you enter your PIN. This makes it possible to access your money if they ever stole your card

60 Sophia Pratzioti Radio Frequency Identification (RFID) Readers Consist of: An Integrated Circuit An Aerial The Aerial Receives and Sends Data RFID readers work in a similar way to barcode readers Radio waves are used to transmit the digital data held on the RFID tag to the reader (range: 300 feet away) The RFID reader does not need a direct line of sight in order to read the tag. Information on the tag can even be read through wallets or clothing

61 Sophia Pratzioti 61 Radio Frequency Identification (RFID) Readers

62 Sophia Pratzioti 62 Radio Frequency Identification (RFID) Readers Uses: In supermarkets and retail stores in order to track good and products To identify pets: an RFID tag is inserted under the skin of the animal. The tag contains details about the animal. In new passports to help improve and speed up the process of identifying passengers in airports.

63 Sophia Pratzioti 63 Radio Frequency Identification (RFID) Readers Advantages (compared to barcode readers) Can hold more data. More detail about products will be store. Data held on RFID tags can be read from longer distances. Tags can be read even without a direct line of slight. Easier to use. Information stored on RFID tags can be read much faster RFID tags are writeable. You can add or alter information already on the tag RFID tags can be made very small Disadvantages (compared to barcode readers) If thieves have access to handled scanner then it is possible to steal information on bank cards and passports. RFID tags and readers are more expensive. The radio signals uses to transmit data from the tag to the reader can experience interference from other devices

64 Sophia Pratzioti Magnetic Ink Character Reader (MICR) MICR is a system which can read information printed in a special ink This is special ink is used to write customer account number on the bottom of cheques Uses: Customer account number Bank sort-code / branch number Cheque number

65 Sophia Pratzioti 65 Magnetic Ink Character Reader (MICR) Advantages Cheques can be processed very quickly Greater security than OCR because the special ink characters cannot be changed No manual input therefore less errors Disadvantages Only a very limited number of different characters can be read MICR devices are expensive Information can still be read even if someone writes over the magnetic ink characters

66 Sophia Pratzioti Optical Mark Reader (OMR) System which automatically reads marks made in pen or pencil Typically used to read multiple choice examinations where students shade in (mark) answers that they think are correct Uses: Multiple choice examinations Multiple choice questionnaires Lottery tickets OMR devices can read the shaded areas on multiple choice tests.

67 Optical Mark Reader (OMR) Sophia Pratzioti 67

68 Sophia Pratzioti 68 Optical Mark Reader (OMR) Advantages Extremely fast way of inputting information into a computer Very accurate as document s data is fed into the computer automatically with no manual typing Can save money as there is no need to employ workers to enter form information into a computer Disadvantages If forms have been incorrectly filled in they cannot be read properly Forms need to be accurately designed to make sure that marks/ shading are in correct position to be read by the device Can only read shaded areas (cannot read text) Forms can jam in the machine as they are fed through

69 Sophia Pratzioti Optical Character Reader (OCR) Optical character readers consist of a scanner along with special software. It allows us to scan text on paper (hardcopy) into a computer OCR software converts the scanned text into a digital format Uses: In the processing of Passports and Identity Cards It is also used in the process of digitizing books

70 Optical Character Reader (OCR) Sophia Pratzioti 70

71 Sophia Pratzioti 71 Optical Character Reader (OCR) Advantages Disadvantages Very fast way of entering hardcopy text into a computer The system can have difficulty reading handwriting Cheaper than paying an employee to manually re-type printed text into a computer Avoids typing errors as the process is automatic (no typing involved) Not 100% accurate As it is not 100% accurate, information needs to be manually checked for errors. This is time consuming

72 7. Bar Code Reader Used to tread information that is stored on product s barcodes The barcode scanner reads the information stored on the barcode using a visible red light which is reflected and translated into digital information The barcode is present on products and holds information about each product including: Product ID number Manufacturer Country of origin Uses: Supermarkets, stores and warehouses Libraries to scan library cards and read ISBN numbers Keeping track of packages Organising luggage in airports Sophia Pratzioti 72

73 Sophia Pratzioti 73 Bar Code Reader Advantages Quick and easy to change product prices Disadvantages Quite an expensive way to gather information Quick and easy way of getting information into a system Very accurate as there is no manual typing involved Barcodes can be swapped on items which means people may pay less for more expensive items If a bar code is damaged, item numbers have to be typed into the system by hand Enables automatic stock control

74 Sophia Pratzioti 74 PART 2.3 OUTPUT DEVICES

75 Sophia Pratzioti 75 Output Devices Definition: Hardware devices that allow information to be sent out of a computer system Some devices produce a temporary output Some devices produce a permanent output

76 Sophia Pratzioti 76 Output Devices Examples of Output Devices: CRT Monitor TFT Monitor Laser Printer Inkjet Printer Dot Matrix Printer Plotter Speakers Multimedia Projector

77 Sophia Pratzioti 77 Output Devices REMEMBER! Output devices send processed information OUT of a computer.

78 1. CRT Monitor Sophia Pratzioti 78 CRT stands for Cathode Ray Tube There are the old, bulky, heavy monitors that are still in use today There are the least expensive types of monitor CRT s becoming rare as TFT monitors are replacing them They are also used with light pens to allow drawings to be created on screen

79 Sophia Pratzioti 79 CRT Monitor Advantages Can be used with light pens to create drawings on screen Disadvantages They are very large and bulky which means they take up large amounts of desk space Produce a larger range of colours than TFT monitors They create a lot of heat and have been known to cause fires The screen angle is better than with TFT s Screen glare when in direct light makes viewing difficult Cheaper to buy than TFT screens They also need more power than TFT s to operate

80 Sophia Pratzioti TFT/LCD Monitor TFT Thin-Film- Transistor LCD Liquid- Crystal Display These are thin flat screened monitors that are commonly seen today TFT s are used with the newer desktop PC s, laptops and mobile phones TFT Monitors allow users to instantly see outputs from the computer They are used as screens in laptops and also mobile phones

81 Sophia Pratzioti 81 TFT/LCD Monitor Advantages Lightweight so they are perfect for portable laptops and wall mounting Disadvantages Images can appear unclear when viewed from an angle The are very thin and so not take up as much desk space as a CRT monitor They use less power than CRT monitors Lower picture quality compared to CRT monitor They emit less radiation than CRT monitors They produce less heat than CRT s Cannot be used with Light Pens yet

82 Sophia Pratzioti IPS/LCD Monitor IPS In-Plane Switching LCD Liquid- Crystal Display Screen technology used in modern LCD monitors, mobile phones, and tablet devices.

83 Sophia Pratzioti 83 IPS/LCD Monitor Advantages Disadvantages Allow for a much wider viewing angle than older monitors IPS screens require greater power than TFT screens Colour reproduction is much more consistent across the screen. More expensive to manufacture

84 Sophia Pratzioti LED Monitor LED Light Emitting Diode LED monitor uses light emitting diodes rather than florescent lighting to backlight the screen. LED display is a flat screen, flat panel computer monitor or television It has a very short depth and is light in terms of weight. The actual difference between this and a typical LCD monitor is the backlighting.

85 Sophia Pratzioti 85 LED Monitor Advantages Disadvantages Lower energy consumption Newer technology can be more expensive Improved image quality compared to older LCD screens Not as effective on very large screens

86 4. Multimedia Projector Sophia Pratzioti 86 These project whatever appears on a computer monitor onto a very large screen so that large numbers people can view it They are usually controlled using a remote control Uses: Can be used for training presentations to allow whole audience to see images from a single computer Also uses for large scale advertising of new products Home cinema systems where images form DVD s are projected to a large screen

87 Sophia Pratzioti 87 Multimedia Projector Advantages Many people to clearly view the same presentation Enhance the viewers experience Disadvantages Lower image quality compared to a computer screen Very expensive to buy Cooling fans in the projector are noisy

88 Sophia Pratzioti Laser Printer These produce high quality hard copy outputs Laser printers use Toner pressed on a page to produce printed documents They can print large amounts of pages at a very quick rate You can buy both black and white and colour laser printers It works by using a laser beam to draw onto drum Uses: Schools Business Offices

89 Laser Printer Advantages Very fast at printing documents Toner cartridges last along time and don t need to be replaced Laser printers can handle high volumes of printing Very quite when printing Very high quality when printing Reliable don t breakdown as easily as inkjet printers Cheaper to run than inkjets (low cost per page) Sophia Pratzioti 89 Disadvantages They are more expensive to buy (but cheap to run) Environmentally unfriendly (produce ozone) they also use more power than inkjets Colour laser printers are much more expensive to buy and run than inkjets They are larger in size compared to other types of printers

90 6. Inkjet Printer Sophia Pratzioti 90 These are used to produce high quality hard copies Although the quality of Inkjet printouts is not as good as Laser printers, it is far better than Dot Matrix printers Ink is stored in and delivered to the paper via ink cartridge Inkjet s can print in both black and white and colour Uses: Good where few printouts are needed Ideal for single-page, very high quality printing Often used to print photographs

91 Sophia Pratzioti 91 Inkjet Printer Advantages Output is very high quality Much cheaper to buy than laser printers Smaller than laser printers so take up less space Do not produce ozone Very quite whilst printing Disadvantages Slow printing rates, especially if several copies are needed Ink cartridges don t last long and so are not suitable for large print jobs Noisier than a laser printer Cost of printouts per page are more expensive than a laser printer If not used for a while the cartridges can dry out

92 7. Dot Matrix Printer Sophia Pratzioti 92 Pins are pressed against an inked ribbon which produces an imprint on paper They use continuous stationary: long, continuous strips of paper Uses: They are very robust and can be used in noisy and dirty environments Can make Carbon copies of a document using special Carbon Paper An example of this is airline tickets which have several duplicate pages, all printed in one go

93 Sophia Pratzioti 93 Dot matric printers are noisy and slow Dot Matrix Printer Advantages Work just fine in dusty and dirty environments where laser and inkjet printers could easily be damages Carbon copies can be produced using carbonated paper Disadvantages Very noisy so not suitable for an office environment Very slow to print Very cheap to buy and maintain Very poor print quality Good for continuous printing

94 Sophia Pratzioti Wide Format Printer - Plotter Produce hard copies but are capable of printing on very large pieces of paper The print quality of plotters is very high Uses: To produce large accurate drawings Plans / designs of buildings Maps Giant posters and adverts

95 Sophia Pratzioti 95 Wide Format Printer - Plotter Advantages They can produce much larger printouts than other printers Disadvantages Their print times are very slow The print quality is extremely high They are very expensive to buy and maintain Plotters can also cut out designs for use in size making Very large and so take up lots of office space

96 9. 3D Printer Sophia Pratzioti 96 They allow us to print three dimensional solid objects in almost any geometrical shape 3D printers follow digital CAD designs which provide the dimensions and shape of the object being printed 3D printers are commonly used to print prototypes within industry. Prototypes are built in order to find any product design flaws before it is mass produced A range of materials can be used when printing including metal, plastic, gold, fabric, acrylic and porcelain Uses: Medical industry Aviation industry Car Industry Personal printing 3D printers are being used to create prosthetic body parts such as ears

97 3D Printer Advantages Sophia Pratzioti 97 Disadvantages Produce prototypes quickly Copyright issues Reduced developments costs Find design flaws early Most printed items are limited in size Anyone can print dangerous items without being checked Your products hit the market earlier High cost of 3D printers Environmentally friendly

98 10. Speakers Sophia Pratzioti 98 They convert electrical signals into sound waves. Enable a computer to output sounds as long as there is a sound card fitted into the computer Uses: To output sound from multimedia presentations Used in home entertainment Can be used to play music files

99 Sophia Pratzioti 99 Speakers Advantages Disadvantages Everyone in the room can hear the sound They can help blind people use a computer because text can be turned into sound Enables computers to be used a multimedia devices such as in video playback with sound Output from speakers can disturb people trying to work High quality speakers can be expensive Require desktop space

100 Sophia Pratzioti Control Output Devices Control Devices are output devices which work together with sensors Data collected by a sensor is input into a computer which then devices what to do with the data Once the computer has decided what to do with the data sends instructions to the control device The control device the physically changes something in response to commands received from the computer

101 Control Output Devices Sophia Pratzioti 101 Some of these devices require an analogue signal to operate them. This means that they need to be connected to the computer using a digital-toanalogue convertor (DAC)

102 Sophia Pratzioti 102 Control Output Devices REMEMBER! Control devices require inputs from sensors and instructions from a computer in order to produce the correct output.

103 Sophia Pratzioti 103 Uses of Control Output Devices Type of Sensor: Motor Used In: Households: Automatic washing machines DVD payer Air conditioners Industry: Controlling robot arms Computer Systems: Spinning disks in hard disk drives Spinning cooling fans Buzzer Microwave ovens Alarm systems Heater Central heating systems Washing machines Automatic greenhouses Light/Lamp Security Lights Automatic greenhouse