Devices I nput C omputer

Input Peripherals Input devices are used to feed data to your computer. The users enter data through input devices, the computer converts it to binary, and then the CPU reads the data. They are connected to the computer via ports to manage the transfer of data between the computer and the devices.

Keyboard Application - Word Processing, The keyboard we normally use has a qwerty layout. Apart from character keys, a keyboard has the function keys, cursor control keys, page control etc.. Pressing a key on the keyboard causes a scan code to be sent to the computer via the keyboard port. Nowadays keyboards are more ergonometric and are being designed to reduce stress.

Advantages and Disadvantages Typists can use with ease. Every computer comes with a keyboard If you are not a fast typist, it can be relatively slow. Note : keyboards can be found with wire and without (wireless)

Mouse Application – Computer Aided Design Used to position the cursor on the screen by moving it about on your tabletops

Different types of Mouse Ball Mouse : which has a ball underneath which as the muse is moved a flat surface enables a corresponding mouse cursor to move in the same direction on the screen. Mouse ball Mouse ball housing

2. Opt mechanical: Same as a mechanical mouse, but uses optical sensors to detect motion of the ball. 3. Optical: Uses a laser to detect the mouse's movement. Optical mice have no mechanical moving parts. They respond more quickly and precisely than mechanical and opt mechanical mice. Note : mouse can be found with wire and without (wireless)

Advantages and Disadvantages Allows diagrams to be easily drawn and modified, therefore it is very versatile for drawing packages. Relatively cheap. Easy and convenient to use. Selects a position on screen more quickly than is possible with a keyboard. Uses more desk space than any other pointing device. It cannot be used to input text Relatively slow for selecting options from menus. Requires a flat surface to operate.

Trackball Application – Drawing Packages and Menu Selection It works exactly like a mouse, except that the ball is rotated by hand. This device was initially used with laptop computers.

Advantages and Disadvantages More finger movement needed to reach buttons than any other pointing device. Uses less desk space than a mouse.

Joystick Application – Playing games and computer simulation Enables the user to control movement on the screen by maneuvering a small lever. It usually has buttons with which actions can be carried out.

Advantages and Disadvantages Allows the fast interaction needed in games. Much easier than using a keyboard. Cannot be used to accurately select options from screen Special interface required.

Touch Pad Application – Menu Selection Touch pads let you control the pointer with your finger. As you move your fingertip, the cursor follows the movement. You click by tapping the finger on the pad’s surface.

Advantages and Disadvantages Less prone to dust. Small active movements makes precise cursor control difficult

Light Pen Application – Computer Aided Design It is a light sensitive device It can be used to write or draw on the screen It has to be used with a device which outputs light When the tip of the pen is placed next to the display screen, light coming from the screen is detected by a photo detector in the tip of the pen. Then the software determines the screen location (x and y coordinates) where the light pen is pointing

Advantages and Disadvantages More direct and precise than using a mouse Easier to draw with Can record only the presence or absence of light Requires software written specially for it

Touch Screen Application – Fast Food and Menu Selection The user need only to point a finger to indicate the location needed.

Different types of Touch Screen LEDs are placed along a vertical and horizontal edge of the screen and a series of photo detectors along the opposite sedges. When the user touches the screen one or more LEDs are blocked in the vertical and horizontal directions so the software can determine the approximate location the user pointed at. A pressure sensitive membrane is placed over the screen. Pressure on this membrane is detected by the computer and then the software calculates the position

Advantages and Disadvantages User just uses his finger It is very useful for people whose work involves a lot of movement or standing up Accuracy of a touch screen is not very good so this restrict them to selecting function “Not useful when needing to input large amount of data

Graphics Tablet Application – Computer Aided Design It is a flat surface that has a fine grid of vertical and horizontal wired embedded in it. Attached to you find the stylus (like a pen) Like the touch sensitive screen the device controller can determine the row/column address of the stylus from the embedded wire mesh It has high resolution

Image Scanner Application – Desktop Publishing It can produce a digital image of a document for input and storage in a computer The technology is very similar to the photocopier

Different types of Scanners Hand Scanner : small scanner that can be passed over the document surface by hand. 2. Flat bed: like a photocopier, on which the input document is placed and scanned

Advantages and Disadvantages No artistic performance is required High quality graphics require large amounts of disc space. Scanned handwriting or text is treated as one whole picture unless u have the specific software.

Digital Camera High resolution pictures can be taken and stored in specially designed storage in the camera The camera can be connected to the computer and pictures can be downloaded Since pictures are digital they can be edited, enhanced and printed

Advantages and Disadvantages Easy image capture Pictures can be send through telephone lines Still relatively costly

Bar Code Reader. Set of bars and spaces of different width. They are used to identify the product purchased. They are used in: Libraries Luggage routing Stocktaking, etc.. Consists of light sensitive and a light emitting diode. Nowadays almost all products are give a UPC (universal product code) Written in 2 forms: human readable and barcode.

Different types of Bar Codes.

Optical Mark Reader (OMR) Allows direct transfer of data from source document to computer. Information obtained by marking with a pencil. It can detect the presence or absence of a mark by shining a light and measure the amount of light reflected. Used for : Questioners Tests Software notices if there are more then one marked boxes.

Optical mark reader paper.

Magnetic Ink Character Reader (MICR) Reads only those numbers written in magnetic ink. It is really accurate and sensitive. It is practically tamperproof. Found in almost every shop. They are used in: Banks and they are the biggest users. Passport control. Significant important documents. Shops to check if money is false.

Advantages and Disadvantages. MICR is difficult to forge Documents can still be read when folded, written etc.. MICR readers and encoders are very expensive. The system can only accept a few different characters.

Magnetic ink character reader.

Optical Character Reader (OCR). It recognizes characters from their shape. Scanners are frequently used for optical recognition. Some can read hand-printed characters (neatly written), typed or printed fonts. How it works: Light is reflected from paper and from ink.

Advantages and Disadvantages. Data can be read and checked by people. Can be programmed to read text and neat handwriting. Documents can be inputted in the computer without the need of re-typing them. Regularly fail to recognize characters. Certain words can be easily mistaken for others.

Pen Computing. Utilizes an electronic pen (called a stylus) rather than a keyboard for input. Some recognize your handwriting and transform it into typed text. Some need to be trained first in order to recognize your handwriting. The most sophisticated do not need any training. They are hand held. Too small for a full size keyboard.

Different types of stylus.

Web Cam Can be used as a Video Conference System, a Home Network System or for Real time Webcam & Web Casting! It is a camera that is in some way connected to the World Wide Web, or Internet. Can take many different forms and flavors. One of the most common types of webcams are personal cameras that are connected to a home PC, which with the help of some software allow the user to share a moving image of themselves with others.

Types of Web Cams.

Speech Recognition Human speech is recorded and coded into a sequence of electrical signals

Advantages and Disadvantages No types or data is necessary The system can be done remotely by telephone, by handicaps and by people whose hands are busy Current speech recognition does not give good results Relatively few words can be recognized and the error rates are high The system is not suitable for noise places

Signature Pad Offers a fully integrated signature capture option that allows users to capture signatures and store them electronically. There are those which are portable and those which are not. There are those which are wireless. There are different types of signature pads and the more they go the more they evolve. Customer information, service applications and teller-based transactions which are recorded electronically.

Types of Signature Pads.

Palm Reader Mostly used for security and privacy, this small device can read your palm. You put your hand in front of it and it scan your fingerprints More evolved palm readers scan vein structures in the user’s hand without touching the device. The device uses infrared light to scan the palm. Data about your hand layout has to be stored on a computer in order to identify if you have access or not.

Palm Reader (scans the fingerprints) Modern palm reader (scans the veins structure).

Future Input Devices 3D - Input Decives

3D Mouse Application – Visual Simulation It provides intuitive and precise interactive motion control of three-dimensional graphic objects Motion control (X, Y, Z, pitch, roll and yaw) without the need for calibration.

SpaceBall 5000

SpaceMouse Plus

Space Traveler

Cadman

3D Joystick Application – Visual Simulation 3D graphics control and manipulation

Ascension Wanda

Inition 3DiStick

Glove

Head-Mounted Display

Made By: Sefora Azzopardi Kirsten Briffa Jeanella Ebejer