The Big Picture Things to think about What different ways are there to collect information automatically? What are the advantages and disadvantages of these methods? Can you describe real life situations where these systems are used? Using Input Devices to Collect Information Automatically Mind Map

Main Lesson Last year we looked in detail at input devices. These are pieces of hardware that put information INTO a computer. Some input devices are designed to collect information automatically. This is what we are going to look at this lesson. On the next slide are links to different automatic input devices. It is your job to find out: Examples of where they are used Advantages Disadvantages Using Input Devices to Collect Information Automatically

Main Lesson Continued Automatic Input Devices MICROMROCR Barcode Reader Magnetic Stripe Sensors Click the icon below to open up the summary spreadsheet that you are going to use this lesson.

MICR Banks each day process millions of cheques. They use a method called Magnetic Ink Character Recognition (MICR) which enables up to 300 cheques per minute to be read with 100% accuracy. Three numbers are printed on the bottom of a cheque: The cheque number The Bank or building society sort code The customer's account number. These numbers are written in a special ink which contains iron particles. This ink is magnetised and commonly called 'magnetic ink'. It can be read by a special machine called a Magnetic Ink Character Reader (MICR). The MICR will only recognise numbers printed in a standard font using the magnetic ink. This provides a high level of security because any attempt to alter the magnetic ink printout with normal ink will be ignored. It is not possible to change the information by writing over it with a pen and the printed numbers are not damaged by folding the cheque. Both the Reader and the magnetic ink are expensive and are mainly only used by banks. Using Input Devices to Collect Information Automatically

OMR An Optical Mark Reader is a scanning device that reads carefully placed pencil marks on a specially designed form or document. A simple pen or pencil mark is made on the form to indicate the correct choice e.g. a multiple choice exam paper or on the National Lottery ticket selection form. The completed forms are scanned by an Optical Mark Reader (OMR) which detects the presence of a mark by measuring the reflected light. Less light is reflected where a mark has been made. The OMR then interprets the pattern of marks into a data record and sends this to the computer for storage, analysis and reporting. This provides a very fast and accurate method of inputting large amounts of data, provided the marks have been made accurately and clearly. Using Input Devices to Collect Information Automatically

OCR Optical Character Recognition (OCR) enables the computer to identify written or printed characters. An OCR system consists of a normal scanner and some special software. The scanner is used to scan the text from a document into the computer. The software then examines the page and extracts the text from it, storing it in a form that can be edited or processed by normal word processing software. The ability to scan the characters accurately depends on how clear the writing is. Scanners have been improved to be able to read different styles and sizes of text as well as neat handwriting. Although they are often up to 95% accurate, any text scanned with OCR needs careful checking because some letters can be misread. OCR is also used to automatically recognise postcodes on letters at sorting offices. Using Input Devices to Collect Information Automatically

Barcode Reader Most items for sale in shops will have a bar code printed on them somewhere. The bar code is a series of vertical bars of varying widths that give information about the country of manufacture, the name of the manufacturer and a product code. The price is not included in the bar code, it is held on a computer database. A bar code reader uses a visible red light to scan and 'read' the barcode. The reflected light is translated into digital data that is interpreted by the computer and the correct price and product information is displayed. A great advantage of using the bar code system is that any price change only needs to be made to the computer system and not each individual items. Library tickets often contain a bar code as do all of the library books. When you borrow a library book, both your ticket and the book are scanned. The library computer system then matches the borrower with the book. When you return the book, it is scanned again and the computer system removes the link between you and the book. This way, the system is able to keep track of which books are out on loan. Using Input Devices to Collect Information Automatically

Magnetic Stripe Magnetic strips are built into many plastic cards such as cheque guarantee cards, cash-point cards and personal identity cards. The magnetic strip on the back of the card can hold the personal details of the card owner and, with the necessary PIN, will allow access to secure information e.g. bank account details. The strip can contain up to 60 characters (numbers or digits) of information which is stored magnetically. Usually the information is put onto the stripe when the card is made and is never changed. To be read the card is swiped through a machine which quickly and accurately reads the pattern of magnetism. Advantages Simple to use and cheap to produce. The data can be altered if necessary. Disadvantages Very limited storage capacity. Data easily destroyed by strong magnetic fields. Not very secure as thieves can obtain the readers and alter the data. Using Input Devices to Collect Information Automatically

Sensors Sensors are used to detect physical quantities outside a computer such as temperature, pressure and light. To be able to process input from sensors a device called an analogue to digital converter must be connected between the computer and the sensors. This device converts signals from sensors into digital data that the computer can process. Using Input Devices to Collect Information Automatically