Specifications

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5.4 Imaging Performance by Settings
Selecting only the symbol to capture
The CMOS Imager can read various kinds of symbols. However, in general, symbols that the user
must read during actual daily operation are very limited only to several kinds. If the image
capturing permission is set in such a way that even unnecessary symbols are included, the search
range for decoding will be widened, the time to complete the capturing will be prolonged, and the
frequency of read errors will increase, unnecessarily. It is strongly recommended to limit the
number of symbols to be given capture permission in accordance with user’s daily application.
Specifying the limited number of digits
In addition to the above mentioned restriction that applies to the selected symbols, each of the
symbols available for the user has a specific number of digits that can be captured. Specifying the
number of digits for which to exceed the given range may cause errors (in particular, an
abbreviated capture). To avoid this, as with the objective symbols specification, specify an
appropriate range of digits for the actual operation.
Check digit calculation
Some symbols contain a check digit (or check character) used to validate the contained data. The
check digit calculation function is essential for these symbols, however, it is recommended to also
apply it to other symbols that allow the selection of this function.
Specifying the print density (“Print Weight”)
Suppose that two sets of black/white bars (cells), both indicating an identical value, are printed on
different surfaces, one of which is normal and the other of which is prone to be affected by the
print intensity of the printer or the reflection from a metallic surface. If these two printed results
have a difference in appearance, it may be possible to improve the capture accuracy with this
function. Use a smaller value if the printed section (dark bar/cell) looks
Fig. 5.10