§ A pointing device just changes your location on the screen (moves the cursor). A scanning device converts printed output into digital input for processing by the computer.
three types of scanners.
§ Scanning devices convert scanned text and images into a form that the system unit can process.
a) Optical Scanners
§ An optical scanner (aka scanner) accepts documents consisting of text and/or images and converts them to machine readable form.
§ They work by recognizing light, dark, and colored areas that make up individual letters or images.
§ Flatbed scanner: works like a copy machine
§ Portable scanner: often is a hand held device that slides across the document being scanned.
§ Typical use is by advertising professionals who scan images and combine them with text.
b) Bar Code Readers
§ Bar code readers/scanners contain photoelectric cells that read bar codes.
§ Typical uses are in grocery stores that use Universal Product Codes (UPC) which match up the product with a database entry containing product information such as price.
§ These devices are either handheld wand readers or platform scanners.
c) Character and Mark Recognition Devices
§ These devices read special characters and marks.
§ Three types include:
o Magnetic Ink Character Recognition (MICR): used by banks for processing checks. Special reader/sorter machines process the checks much faster than the older manual methods
o Optical Character Recognition (OCR): use special pre-printed characters that can be read by a light source, and are still understandable by human readers. Retail stores frequently used these types of scanners.
o Optical Mark Recognition (OMR) aka Mark Sensing: frequently used to score multiple choice tests marked by pencil on a form.
The handheld scanner is a scanning device where the scanning element is built inro a small handheld unit. The handheld unit is then waved or rolled over the item being scanned. barcode scanning devices
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