Symbol MiniScan MS-120X, Руководство по интеграции

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6-6
MS-120X and MS-220X Integration Guide
MS-2204VHD Decode Zones
The decode zone is a function of various symbol characteristics including density, print
contrast, wide to narrow ratio and edge acurity. Typical values are shown.
Table 6-3 on
page 6-7 and Table 6-4 on page 6-9 list the typical and guaranteed distances for selected
bar code densities. The minimum element width (or “symbol density”) is the width in mils of
the narrowest element (bar or space) in the symbol. The maximum usable length of a
symbol at any given range is shown below. To calculate this distance, see
Calculating The
Usable Scan Length Method on page 2-14.
MS-2204VHD 1D Decode Zone
Figure 6-3. MS-2204VHD 1D Slab/Raster Decode Distances
In.
cm
0
7.5 mil
55 mil
15.0
Depth of Field
5.25
Note: Typical performance at 68˚F (20˚C)
on high quality symbols in normal room light.
Vcc = 5V
2.5 5 7.5 10 12.5
0 12.7 25.4 38.1 50.8 63.5
5 mil
4.75
4 mil
4.1
2.0 3.4
15
76.2
6 mil
0
In. cm
W
i
d
t
h
o
f
F
i
e
l
d
0
2.5
5
7.5
2.5
5
7.5
5.1
10.1
15.2
5.1
10.1
15.2
10 25.4
10 25.4
1.75
1.5
*
* Minimum distance determined by symbol length and scan angle.
MS 2204VHD