chapter 03 io csc&tts

Discovering Computers Fundamentals,

2011 Edition

Living in a Digital World

CHAPTERTHREE

2

Objectives Overview

Identify the keys and buttons commonly found on desktop

computer keyboards, and describe how keyboards for

mobile computers and devices differ from desktop computer

keyboards

Describe different mouse types

Describe various types of touch screens and explain how a touch-sensitive pad works

Describe various types of pen input

3

Objectives Overview

Explain other types of input

Explain the characteristics of LCD monitors, LCD

screens, and CRT monitors

Summarize the various types of printers

Identify the purpose and features of speakers, headphones, and ear-

buds; data projectors; and interactive whiteboards

Identify input and output options for physically

challenged users

4

What Is Input?

• Input is any data and instructions entered into the memory of a computer

5

What Is Input?

An input device is any hardware component that allows users to enter data and

instructions into a computer

6

Keyboard

• A keyboard is an input device that contains keys users press to enter data and instructions into a computer

7

Keyboard

• Most desktop computer keyboards have…

Between 101 and 105 keys

A numeric keypad on the right side of

the keyboard

Function keys, CTRL keys, ALT

keys, and arrow keys

WINDOWS key APPLICATION key Toggle keys

8

Keyboard

• An ergonomic keyboard has a design that reduces the chance of wrist and hand injuries

• Ergonomics incorporates comfort, efficiency, and safety into the design of the workplace

9

Keyboard

• Keyboards on mobile devices typically are smaller and/or have fewer keys

• Some phones have predictive text input, which saves time when entering text using the phone’s keypad

Page 191 Figure 5-3

10

Pointing Devices

A pointing device is an input device that allows

a user to control a pointer on the screen

A pointer is a small symbol on the screen whose location and

shape change as a user moves a pointing device

Page 189

11

Types of Pointing Devices:

• Mouse• Devices used for games - joystick• Devices used in laptops – track ball, touch pad,

pointing stick

12

Pointing Devices

• A mouse is a pointing device that fits under the palm of your hand comfortably– Most widely used pointing device on desktop

computers• A mouse can be wired (mechanical/ optical) or wireless

(cordless)

13

Types:

• Mechanical – small ball on underside rolls as mouse is moved

• Optical – uses a light beam to monitor mouse movement

• Cordless – uses either infrared or radio waves

14

Pointing DevicesTr

ackb

all • A trackball is a

stationary pointing device with a ball on its top or side To

uchp

ad • A touchpad is a small, flat, rectangular pointing device that is sensitive to pressure and motion Po

intin

g Sti

ck • A pointing stick is a pressure-sensitive pointing device shaped like a pencil eraser that is positioned between keys on a keyboard

15

Pointing Devices

• A handheld vertical lever with handgrip mounted on a base

• User moves the lever in different directions to control the actions of the simulated vehicle or player

• Distance and speed of movement control pointer position

• Pressing trigger causes actions to take place.

16

Touch Screens and Touch-Sensitive Pads

• A touch screen is a touch-sensitive display device• Position of finger on screen determines item to be input into system• Used at kiosks in public place such as malls

17

Touch Screens and Touch-Sensitive Pads

Microsoft Surface Touch-sensitive pads

18

Graphic tablet

• A flat, rectangular, electronic, plastic board

• Architects, mapmakers, designers, artists and home user create drawings by using a pressure sensitive pen (stylus) on a graphic tablet

• Used to create or trace precise drawings.

19

Pen Input

• With pen input, you touch a stylus or digital pen on a flat surface to write, draw, or make selections

• A stylus -A small metal or plastic device that looks like a tiny ink pen. Often used in PDAs or pocket PCs• A pen digital- provide more functionality than a stylus, featuring electronic erasers and programmable buttons

20

Other Types of Input

21


• Video games and computer games use a game controller as the input device that directs movements and actions of on-screen objects

Gamepads

Joysticks and Wheels

Light guns Dance pads

22


23


• A digital camera is a mobile device that allows users to take pictures and store them digitally

Studio cameras

Field cameras

Point-and-shoot camera

24


25


• Two factors affect the quality of digital camera photos:

• Resolution is the number of horizontal and vertical pictures in a display device

• A pixel is the smallest element in an electronic display

Resolution

26


• Voice input is the process of entering input by speaking into a microphone

• Voice recognition is the computer’s capability of distinguishing spoken words

• Audio input is the process of entering any sound into the computer.

**used – microphone - CD/DVD/Blu-ray Disk Players, - MIDI (musical instrument digital interface)-

external music devices such as electronic keyboard, guitars, drums, harmonica.

27


• Music production software allows users to record, compose, mix, and edit music and sounds

28


• Video input is the process of capturing full-motion images and storing them on a computer’s storage medium

Record video on a digital video (DV) camera or use a video capture card to convert analog signals to digital

Connect the camera to a port on the system unit

Transfer video and images

29


• A Web cam is a type of digital video camera that enables a user to:

Capture video and still images

Send e-mail messages with

video attachments

Add live images to instant messages

Broadcast live images over the

Internet

Make video telephone calls

30


• A video conference is a meeting between two or more geographically separated people

31


• A flatbed scanner creates a file of the document in memory– Works in a manner similar to a copy machine

32


• Optical character recognition (OCR) involves reading characters from ordinary documents

• A turnaround document is a document you return to the company that creates and sends it

33


• Optical mark recognition (OMR) reads hand-drawn marks such as small circles or rectangles

34


• A bar code reader, also called a bar code scanner uses laser beams to read bar codes

35


• RFID (radio frequency identification) uses radio signals to communicate with a tag placed in or attached to an object

• An RFID reader reads information on the tag via radio waves • RFID can track:

Tracking times of runners in a marathon

Tracking location of soldiers

Employee wardrobes Airline baggage Checking lift

tickets of skiers

Managing inventory

Gauging pressure and temperature

of tires

Checking out library books

Tracking toll payments

36


• Magnetic stripe card readers read the magnetic stripe on the back of cards such as:

Credit cards

Entertainment cards

Bank cards

Other similar cards

37


• MICR (magnetic ink character recognition) devices read text printed with magnetized ink

• An MICR reader converts MICR characters into a form the computer can process

• Banking industry uses MICR for check processing

38


• Biometrics authenticates a person’s identity by verifying a personal characteristic

Fingerprint reader

Face recognition

system

Hand geometry

system

Voice verification

system

Signature verification

system

Iris recognition system

Retinal scanners

39


fingerprint reader

iris recognition

system

40


• A terminal is a computer that allows users to send data to and/or receive information from a host computer

A POS terminal records purchases,

processes payment, and

updates inventory

An automated teller machine

(ATM) allows users to access their bank accounts

A DVD kiosk is a self-service DVD rental machine

41

What Is Output?

• Output is data that has been processed into a useful form

42

Categories of output:

• Text : memos, letters, press releases, report, classified advertisements, envelops, mailing labels, text messages.

• Graphics : logos, charts, drawings, clip arts, photos.

• Audio : songs, narrations, speeches• Video : video blogs, vodcast.

43

What Is Output?

• An output device is any type of hardware component that conveys information to one or more people

Display devices Printers

Speakers, headphones, and earbuds

Data projectors

Interactive whiteboards

44

Display Devices:

• A display device visually conveys text, graphics, and video information

• Information on display device sometimes called softcopy

• A monitor is packaged as a separate peripheral

• 2 types of display devices:– Flat -panel display ( LCD,

plasma, digital television /DTV)

– CRT monitors

45

Display Devices :Flat-panel display • Liquid crystal display (LCD) uses a liquid compound to

present information on a display device• Produce sharp, flicker free images• Mobile devices that contain LCD display : Notebook, Tablet

PC, ultra personal computer, portable media player, smart phone and PDA

Page 209

46

Resolution Response time

Brightness Dot pitch

47

Resolution:

• Number of a horizontal and vertical pixel in a display device.

• Sharpness and clarity of images• Higher resolution makes image sharper, display

more text on the screen, makes some elements smaller.

48

Dot pitch:

• Distance in millimeters between pixel on a display device.

• Text created with a smaller dot pitch is easier to read.

• Average dot pitch on LCD monitors and screen should be 0.30mm or lower. The lower the number, the sharper the image.

49

Response time:

• The time in milliseconds (ms) that it takes to turn a pixel on or off.

• LCD monitor’ and screens’ response time today range from 3 to 16 ms. The lower the number, the faster the response time.

50

Brightness:

• Measured in nits. A nit is a unit of visible light intensity equal to one candela per square.

• Candela is the standard unit of luminous intensity.• LCD monitor and screen range from 250 to 550

nits. The higher the nits, the brighter the images.

51

Contras ratio:

• Describe the difference in light intensity between the brightness white and darkest black that can be displayed on an LCD monitor.

• Contrast ratios today range from 500:1 to 2000:1. higher contrast ratios represent colours better.

52

Display Devices:Flat-panel display

• Plasma monitors are display devices that use gas plasma technology and offer screen sizes up to 150 inches

53

Display Devices:Flat-panel display

• Digital Television (DTV) -Uses digital signals to produce crisper, higher-quality output on LCD and plasma televisions

• HDTV (high-definition television) is the most advanced form of digital television.

• Great for game playing, watching movies, and browsing the Internet

54

Display Devices: CRT monitor

• A CRT monitor is a desktop monitor that contains a cathode-ray tube

Page 210 Figure 5-33

55

• Screen coated with tiny dots of phosphor material. Each dot consist of a red, blue and green phosphor.

• What determines the quality of a CRT monitor?– Screen resolution– Text created with a smaller dot pitch is easier to read.– Refresh rate is speed at which monitor redraws images

on screen.

56

Printers

• A printer produces text and graphics on a physical medium

• Before purchasing a printer, ask yourself a series of questions

57

Printers

58

Categories of printer:

• Non impact printer (Int-jet, Photo,Laser, Thermal,Mobile, Label,

Postage, Plotter and multifunction peripheral (MFP)

• Impact printer. (Dot matrix and line)

59

Printers : Non impact printer

• A nonimpact printer forms characters and graphics on a piece of paper without actually striking the paper

Ink-jet printers

Photo printers

Laser printers

Thermal printers

Mobile printers Plotters

Large-format printers

60


• An ink-jet printer forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper– Print in Color or black-and-white– Printers with a higher dpi (dots per inch) produce a higher

quality output– Less expensive than laser printer

61

Printers: Non impact printer

A photo printer produces color photo-lab-quality pictures• Most use ink-jet technology• PictBridge allows you to print photos

directly from a digital camera• Print from a memory card and preview

photos on a built-in LCD screen

62


63


Laser printer

• print text and graphics in high quality resolution, ranging from 1200 to 2400 dpi.•Typically cost more than ink jet printer, but is much faster

64


• A multifunction peripheral (MFP) is a single device that prints, scans, copies, and in some cases, faxes– Sometimes called an all-in-one device

65


• A thermal printer generates images by pushing electrically heated pins against the heat-sensitive paper

Pages 215 – 216 Figure 5-40

2 types:1. Dye-sublimation printer2. Thermal wax printer

66


• A mobile printer is a small, lightweight, battery-powered printer that allows a mobile user to print from a mobile device


67


• Plotters are used to produce high-quality drawings

• Large-format printers create photo-realistic quality color prints on a larger scale


68


• Label printer : Small printer that print on adhesive –type material.

• Most also print bar codes• Postage printer has built-in digital scale and print

postage stamps.

69

Printers: Impact printers

• Impact printers form characters and graphics on a piece of paper by striking a mechanism against an inked ribbon that physically contacts the paper

Page 217

Dot-matrix printer

Line printer

70


• A dot-matrix printer produces printed images when tiny wire pins on a print head mechanism strike an inked ribbon

• Speed measured by the number of character per second (cps)


71


• A line printer prints an entire line at a time

• High speed impact printer

• Speed measured in lines per minute (lpm)


72

Other Output Devices

• An audio output device produces music, speech, or other sounds


Most computer users attach speakers to their computers to:• Generate higher-quality sounds for playing

games• Interact with multimedia presentations• Listen to music• View movies

73


• Headphones are speakers that cover or are placed outside of the ear

• Earbuds (also called earphones) rest inside the ear canal

74


Voice output occurs when you hear a person’s voice or when the computer talks to you through the speakers• Some Web sites dedicate themselves to

providing voice output• Often works with voice input• VoIP uses voice output and voice input

Page 218

75


• A data projector is a device that takes the text and images displaying on a computer screen and projects them on a larger screen


76


• An Interactive Whiteboards is a touch-sensitive device, resembling a dry-case board, that display the image on a connected computer screen.

• A presenter control the computer by clicking a remote control, touching the whiteboard, drawing on or erasing the whiteboard with a special digital pen and eraser, or writing on a special tablet.

• Notes written can be directly on the computer.

77

Putting It All Together

78


79


80

Input and Output Devices for Physically Challenged Users

Braille printerHead-mounted pointer

81

Summary

Various techniques for entering input and several commonly used input device

Various methods of output and several

commonly used output devices

Discovering Computers Fundamentals,

2011 Edition

Living in a Digital World

CHAPTER 3

chapter 03 io csc&tts

Technology