Chapter 1 - Input Devices

stylus

A pointed tool for writing or drawing or engraving

Optical Mark Recognition/ reader (OMR)

Input devices that reads simple multiple-choice style answers by looking for marks on the paper.

Mouse

A hand-operated electronic device that controls the coordinates of a cursor on your computer screen as you move it around on a pad. Usually has 2 buttons (used for selection & other functions) & a scroll up/down wheel.

Input Devices

Any device that allows a computer to retrieve data 'from the outside world'. It essentially is a piece of hardware that SENDS DATA TO a computer

Types of Scanners: (3)

Flatbed, sheet-fed, handheld, and drum

Hardware

The physical components of a computer.

graphic tablet

it converts graphics and pictorial data into binary inputs. A graphic tablet as digitizer is used for doing fine works of drawing and image manipulation applications.

Pressure sensor applications

- detect intruders in a burglar alarm system - weigh things (e.g. check weight of a vehicle) - monitor/control a process where gas pressure is important

Acoustic/sound sensor applications

- pick up noise levels (e.g. footsteps in a burglar alarm system) - detect the noise of liquids dripping in a pipe

Magnetic stripe/ Magnetic strip codes

1) A credit card, entertainment card, bank card, or other similar card with a stripe that contains information identifying you and the card. 2) Magnetic stripes are actually the black or brown strips you see on the back of your credit card. Magstripes are also found on the reverse side of identification cards, driver's licenses, library cards, gift cards, and membership cards.

How Digital Cameras Work

1) Images captured when light passes through the lens onto a light-sensitive cell, which is made up of thousands of tiny elements (pixels). 2) No. of pixels determines the size of the file needed to store the image.

webcam

A camera that broadcast images through the Internet through a computer or web cell phone.

smart card reader

A device that can read a smart card used to authenticate a person onto a network.

smart card

A device that is around the same size as a credit card, containing embedded technologies that can store information and small amounts of software to perform some limited processing

Touchscreens

Accept input by allowing the user to place a fingertip directly on the computer screen. Used in phones/tablets.

Touchpads

Input Device. Used in many laptops as a pointing device; pointer controlled by user moving finger on touchpad and tapping to simulate left hand button of mouse. May have buttons under touchpad.

Microphones

Input device for sound data. A microphone captures audio and sends it to a computer where it is converted to a digital format. Once the audio has been digitized, it can be played back, copied, edited, uploaded, or emailed. Microphones can also be used to record audio or to relay sounds live as part of a video chat or audio stream.

Voice Recognition

Uses microphones to identify if a 'known' person is speaking in (e.g. security systems). Works by comparing wave patterns from the person's voice w/ wave patterns stored in memory. (Matching wave patterns = correct person.)

Scanners

- Used to input hard-copy documents. - Scanned images from image files (e.g. JPEG) - Computers equipped w/ Optical Character - Recognition (OCR) software allow scanned text from the document to be converted into a text file format

How does a Scanners Work

1) Open the scanner to glass plate. 2) Place the document that we need to scan over the glass plate. 3) The scanning unit emits light. 4) Translating drawings, photo, ea=tc into digital form(soft copy)

Barcode Reader/Scanner

1)A barcode reader/ barcode scanner, also called a price scanner or point-of-sale ( POS ) scanner, is a hand-held or stationary input device used to capture and read information contained in a bar code. 1) Is an electronic device that decodes and physically captures information contained in barcodes. It consists of the following components, which work together to collect the data contained in a printed barcode:

biometric reader

A device used to input biometric data, such as an individual's fingerprint or voice.

Digital Cameras

A digital camera is a hardware device that takes photographs and stores the image as data on a memory card.

Trackball

A pointing device with a ball on the top which controls the on-screen cursor. Unlike a mouse, the trackball does not physically move.

Interactive Whiteboards

Allow images to be displayed using a digital projector. User able to write on the whiteboard & the text/images created can then be stored in a computer memory. Any image projected onto the screen can be annotated/changed & the annotated version can then be saved for later use.

pointing stick (TrackPoint)

Alternatively referred to as a pointing stick, style pointer, or nub, TrackPoint is a mouse solution used with portable computers that was first introduced by IBM in 1992. It is a small, isometric joystick that resembles a pencil's eraser head, located between the "G," "H," and "B" keys on the keyboard.

Pointing Devices

Control the position of the cursor or pointer on the screen and allow the user to select options displayed on the screen.

Sensors

Devices that collect input from the environment and provide information that the CPU can respond to. Often req. analogue to digital (ADC) to change the data into a format that the computer/microprocessor can understand.

Magnetic Ink Character Recognition / reader(MICR)

Input device that reads text written in special magnetic ink. Often used at the bottom of cheques.

Joysticks

Joysticks are commonly used to control characters and vehicles in computer video games. Essentially, a joystick is a handle that pivots on a base and sends its angle or direction to the computer as data. Many video gaming joysticks feature triggers and buttons that can be pressed to use weapons or projectiles in games.

Keyboards

Keyboards are the most common type of input device. Before keyboards, interaction with computers was generally carried out using punch cards and paper tape. Most English language keyboards use the QWERTY layout for the alphabetic keys, which are surrounded by number, symbol, function, and other key types. By pressing the relevant keys, a user can feed data and instructions to the computer.

Speech Recognition

Uses microphones. Converts speech pattern into digital form. Digital image is then broken up into phonemes which are compared to words stored in the built in dictionary. The spoken words can then be recognised.

light pen

an input device used like a pencil. It emits an electronic signal to the screen in the exact spot where entry is needed. Light pens do not work on all types of computer screens

types of biometric devices

fingerprint reader, face recognition system, hand geometry system, voice verification system, signature verification system, iris recognition system

Optical Character Recognition (OCR)

scanning text printed on paper and translating the images into words so it can be manipulated on the computer