Motorola Symbol LS4278 Product Reference Manual page 39

When scanning using a multi-line scan mode, at least one scan line must cross every bar and space of the symbol.
012345
Acceptable and Incorrect Multi-Line Aiming
Figure 2-3
Regardless of the scan mode, the scan line is smaller when the scanner is closer to the symbol and larger when it
is farther from the symbol. Scan symbols with smaller bars or elements (mil size) closer to the scanner, and those
with larger bars or elements (mil size) farther from the scanner.
Do not hold the scanner directly over the bar code. Laser light reflecting directly back into the scanner from the bar
code is known as specular reflection. This specular reflection can make decoding difficult.
NOTE Scan line lengths vary depending on the scan line width selected. A full scan line width is the default.
Medium and short scan line widths are useful for scanning menus or pick-lists.
For more information about scan line widths and scanning modes, see
The scanner can be tilted up to 65° forward or back and achieve a successful decode
quickly shows what tolerances to work within.
Maximum Tilt Angles and Dead Zone
Figure 2-4
o
65
o
65
Scanning
012345
page 5-9 and page 5-10, respectively.
(Figure 2-4). Simple practice
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