Input Devices

Input Devices

1. Bar Code Reader

   • Scan a bar code using red light, reflected light is translated into digital data, used to identify product and price from the database
   • Used in supermarkets to scan items, used to show a books ISBN number
   • Any price change will need to be made to the database, prices need updating due to sales

2. MICR

   • Used to read magnetised ink which can be then stored by the computer
   • used for processing bank cheques
   • Both the reader and the ink are expensive so are only feasible for banks

3. Digital Camera

   • A digital camera encodes digital images and videos digitally. Use lenses with a variable diaphragm to focus light onto a pickup device. Shutters admit how much light is entered
   • used for Video recording and taking photos
   • they have quick operating speeds and you can preview images. They are however expensive and easy to break

4. Keyboard

   • They keyboard is the most common and widely used input device. It is made up of buttons called keys arranged in a QWERTY layout.
   • Keyboards are used to input data quickly and perform different commands and shortcuts
   • Skilled typists can enter data quickly, need little training, can lead to RSI

5. SMART Cards

   • A smart card is a card with integrated circuits. it is inserted into a smart card reader similar to an ATM and a transaction will occur.
   • Access cards, Credit cards, Discount cards
   • Reusable, allow for secure transactions off-line reducing the cost for inline networks. Fees applied with the use of a card

6. Pointing Devices

   • For laptops and computers, moving pointer on a GUI
   • A pointing device found on most PCs. Sensors on the bottom of the mouse detect when the mouse is moved. Data about this movement is moved
   • Accurate & fast

7. OCR

   • A scanner along with special software used to scan text from a document into the computer. it then examines the page and changes the letters into a form that can be edited and processed
   • Automatically recognises postcodes on letters at sorting offices
   • Cheaper than paying someone to enter data, faster than someone entering large amounts of text, can recreate original formats. Not 100% accurate

8. OMR

   • Scan forms by detecting the presence of pencil marks. They do this by reflecting light on to the form. Where there is a mark less light is reflected. it then interprets the pattern and sends them to the computer for storage
   • Used on multiple choice tests and national lottery tickets
   • Fast method of inputting large amounts of data, you only need one computer, more accurate than keyed in data. If the marks are dark enough they may not be read correctly, only suitable for recording one out of an option, needs pre-prepared answers

9. Sensors

   • Sensors detect physical quantities outside of computers. They collect data automatically at regular intervals and this can be transmitted real time or in batches. To process this input and analogue to digital converter is required
   • Used as Temperature sensors, Pressure sensors and light sensors
   • People are not required to collect the data however data collected may not be correct or useful

10. IWB

    • Very expensive to buy and maintain, they can break easily. They are easy to use broaden the use of e-learing and enhance presentations
    • Used in schools and business presentations
    • Made up of a computer, a projector, appropriate software and the display panel. The computer is connected to the projector and the white boards. The projector displays the computer screen image onto the board. Action on the surface of the display panel is communicated with the computer over a cable or wireless connection and interpreted via cable

11. Speech input

    • The sound is detected by the microphone and an electrical signal is transmitted to the computer. Hardware is used to convert this analogue data into digital data so it can be stored and manipulated.
    • For blind people to use computers. smart phones, smart TVs, NASA
    • Often it doesn't understand you correctly. It can break. It can help people become less isolated, it can save time.

12. Touch Screens

    • You view options available to you then use your finger to touch the option that you have chosen
    • Used in ATM's, Smart phones, ticket collection at airports and information centres at museums
    • Not very accurate, they can be tiring to use, they are portable and they are easy to use