Appendix C - Orientation; Figure A-3 Ladder Orientation; Figure A-4 Picket Fence Orientation; Label Orientation - Microscan MS-7100 User Manual

Appendices
Appendix C — Orientation

Label Orientation

If the bar code label bars are parallel to the direction of travel, as shown in
figure A-3, the label is said to be in a ladder orientation; if the bars are per-
pendicular with the direction of travel, the label is said to be in a picket fence
orientation (figure A-4).
Ladder Orientation
In general, depending on label size
and speed, ladder orientation is pref-
erable because different portions of
the label are scanned as the label
goes by. In addition, label placement
is not as critical. As shown in figure
A-3, a label can be successfully read
if fully placed (including quiet zones)
anywhere within the readable portion
of the scan line.
Picket Fence Orientation
Unlike ladder, picket fence allows
only a small portion of the entire
label to be scanned. As a result,
labels must be of good quality since
even slight label imperfections such
as extraneous ink, voids, etc., can
cause misreads or non-reads.
One advantage of the picket fence
over the ladder orientation is in the
area of label speed. In ladder mode, the label travel distance is the height of
the bar code; in picket fence mode, the label can be read while it travels the
full distance of the scan width.
Note: Either ladder or picket fence can be rotated without losing its orien-
tation, provided that the label's direction of travel does not change in rela-
tion to the scan line.
A-6
MS-7100/7180 Industrial Scanner User's Manual
Direction of label travel
Scan Line

Figure A-3 Ladder Orientation

Direction of label travel
Scan Line

Figure A-4 Picket Fence Orientation