User`s guide

APPENDIX F: PDF417 AND THE ISC-X | 43
skewed or angled. The ISC-X should be held at a distance such that the
horizontal beam line extends past the sides of the symbol. For best results,
the scanner should also be held at an angle of at least 15 degrees from
perpendicular to the surface of the bar code label, as the reflected light from
the scanner can blind the reading mechanism.
Please see the following examples:
Example 1: Vertical sweep
CORRECT
INCORRECT INCORRECT
The sweeping motion can be either upward or downward, but the beam line
must be parallel with the bottom (or top) of the symbol – it cannot be
skewed or angled. The ISC-X should be held at a distance such that the
horizontal beam line extends past the sides of the symbol.