Rockwell Automation 2755-L7, -L9 Scanners - Manual (Page 17)

Chapter 3
Installation Considerations
3–4
Figure 3.5
Positioning Terminology
Pitched package
and symbol
Tilted, over square
symbol
Correctly positioned
symbol and package
Skewed package
and symbol
When setting up a raster scanner, the raster pattern can either overlap the
entire symbol, or be restricted to cover only a portion of the symbol.
Overlapping the symbol helps to aid in the scanning of misaligned symbols.
Restricting, or dithering the raster pattern is helpful when scanning symbols
of poor quality. Refer to Figure 3.6.
Figure 3.6
Raster pattern