Mark Reading (mark scanning; optical mark reading) Definition/Meaning:
A method for data input in
which marks made on preformatted documents are sensed by photoelectric means.
The marks are interpreted as either characters or values according to their
position on the form. This provides an efficient type of data input in
applications in which there are relatively few answers to a limited number of
questions. No further data preparation activity or machines are required since
the reader can be connected directly to the system.
The mark reading document is often printed on 80 column punch card stock for ease of automatic handling. Some
punch card readers are designed to read punchings and/or marks. The accuracy of
placement of pen or pencil marks cannot be as precise as the punchings so it is
usual to provide no more than 40 columns for sensing the marks, i.e. each mark
can cover the space of two columns of punching. Special readers are available to
handle larger documents. The documents are printed on paper, and information to
the user as to where the marks should be put and what significance they will
have is
usually printed in a color that will not be detected by the photoelectric
sensors. Machine-readable timing marks are preprinted along the edge of the
document.
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