Chapter 7, Problem 20SG

Explanation of Solution

Types of scanners and reading devices:

• Optical scanners: An optical scanner is a light-sensing input device that reads printed information such as text and graphics and converts them into a digital form so that the computer can process them.
  • The scanner captures information directly from a source document, which is the original form of the information. Source documents are classified as brochures, paychecks, time cards, photos, order forms, advertisement, invoices or any other documents.
  • Scanner copies the file from the machine and generate a file of the document in the computer memory.
  • Then, the copied file or photos can be viewed on the screen.
• Optical readers: An optical reader uses a light source to read characters, codes, marks, and converts them into digital data so that a computer can process them. It uses the following two technologies,
  • The Optical Character Recognition (OCR) devices contain a small optical scanner for reading characters and sophisticated software to analyze the characters.
  • Optical Mark Recognition (OMR) devices can read hand-drawn marks, such as small rectangles or circles. OMR software reads the marks in the test or survey forms. This software also reads and converts hand-drawn marks into electronic files.
• Bar code readers: A bar code uses laser beams to read the bar code labels. A bar code is an identification code that contains numbers and a pattern of parallel lines, dots, space of different widths.
  • For quick identification, bar codes are labelled to a product or a package of the product such as clothing, mail, books, groceries, vehicles, and other packages...