Specifications

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5.3 Imaging Performance by Print Quality
Print quality
Generally, a printer that has a resolution higher than 400 dpi is considered as capable of printing
symbols at a dot size smaller than 0.125 mm. In an actual application it is preferable to perform
printing so that one fine bar (cell) consists of 3 to 5 dots, and in that case, the resulting dot size
will be between 0.18 to 0.38 mm.
Some printers have the capability to emphasize fine lines, which may produce a difference in the
width of black/white bars (cells) from that produced with other printers, even if these two
black/white bars (cells) indicate an identical value. In this case, increase the width of the fine bars
(size per cell) of each symbol to relatively reduce the difference.
Also, if a symbol is duplicated by a copy machine or sent through a facsimile, the print quality of
the entire symbol is reduced. The readability becomes less than the original. Also, in this case it is
possible to restrict the relative error by printing the symbol so that it becomes larger in size than
the original. However, an enlarged copy is useless, since the printing error must also be relatively
enlarged. Even with the given print quality it is sometimes possible to improve readability by
specifying “Print Weight”, as described..
Margins around a symbol, character, figure, peripheral object
A CMOS Imager is different from a laser scanner and will capture a symbol in terms of the area.
Therefore, the resulting image may contain characters, figures, and objects other than the target
symbol and may require an extended period of time to detect the symbol and increase the
frequency of read errors, if a complex picture is captured. To avoid this problem it is
recommended to provide a sufficient margin around the symbol and to refrain from printing
unnecessary characters and figures.
1D symbol: 2D symbol:
Fig. 5.7
Fig. 5.8
10 times of fine bar or 2.5 mm whichever is larger. 4 times larger than one cell.