Page 18 - CA 165 ver 1.0 Class 9
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Scanner
                  A scanner is a device that scans a document by sensing the reflection
                  that is received when the scanner emits rays on the content. It takes
                  the image of content and converts it into a digital file.

                  The scanned images or photos can be stored in a computer and can
                  be easily transferred to a secondary storage device. Scanners can be
                  categorized as ‘Hand held scanner’ and ‘Flatbed scanner’.

                                         Optical Mark Reader (OMR)
                                         OMR is an input device which can detect the marks on a paper. It is used to
                                         evaluate answer sheets in which selected answers are marked in dark circles.

                                         It is used to read or detect marked answers by sensing the marks made on the
                                         answer sheet by exposing the sheet to a beam of light.




                  Magnetic Ink Character Reader (MICR)

                  MICR is a device which is used by banks for processing cheques by interpreting
                  information stored in MICR code (printed at the bottom of cheque)

                  On the cheques, the code of name of the bank,  branch  code and  cheque
                  number are printed with a special kind of ink containing magnetic particles or
                  iron oxide which is scanned & read with the help of MICR and accordingly
                  processed in the computer. A MICR code consists of nine (9) digits.


                       Do you know?

                       A magnetic stripe has the holding capacity of about 1024 bits of information.



                                                   Light Pen

                                                   A ‘Light Pen’ is a pen like device which uses a light sensitive detector to
                                                   select or draw objects on the display screen.
                                                   It is similar to a mouse, except that with a light pen one can move the
                                                   pointer on the screen by touching it to the objects on the screen. When
                                                   the pen is moved across the screen, its position is sensed because of
                                                   the light it emits.


                  Bar Code Reader
                  A Bar Code Reader is a popular scanning device which reads the bar codes. Bar
                  code comprises of adjacent vertical black bars of different width. A barcode stores
                  information about a product, eg: its price, weight, manufacturing details etc.







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