2.5. Optical Mark Reader
Optical mark readers (OMR) optically read marks on carefully printed forms. Optical mark forms are relatively expensive, as they must be printed with exact tolerances so that the marks will up under the optical sensing devices when read. The most popular use of such devices is optical character readers for scoring examinations in educational institutions.
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2.6. Optical Character Recognizer
Optical character recognition (OCR) devices can convert data from source documents to a machine-recognizable form. OCR Current applications of optical scanning include billing, insurance premium notices, and charge sales invoices. At present, on OCR device can reliably read and interpret script or handwriting.
However, some can read handwriting provided that certain general guidelines are observed when the data are written. Generally, optical character readers are limited with respect to hand-written characters and can only read handwritten digits and some symbols. Many OCR devices are available for the reading of typed characters, including digits, letters and some special characters. Not all printed characters can be read reliably on OCR readers. Generally, each reader is capable of reading only selected character styles.
Even if the character style and spacing are acceptable, errors can result from reading a character that is not written perfectly. To reduce such errors, OCR devices generally compare the pattern read with the patterns to all acceptable character. The read character is assumed to be the character whose stored pattern most closely matches the read pattern.
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