Symbol LS 1220, Руководство по продукции

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3-5
LS 1220-I300A Standard Version
Decode Zone (V
cc
= 5V)
The standard LS 1220-I300A decodes the symbols as shown in Figure 3-2. The figures
shown are typical values. Table 3-2 on page 3-6 lists 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. Calculating The Usable Scan Length
Method on page 2-5
LS 1220-I300A Standard Range Decode Zone
Figure 3-2. LS 1220-I300A Decode Zone (Typical)
In.
cm
0
0 5
12.7
10
25.4
15
38.1
20
50.8
25
63.5
30
76.2
35
88.9
LS 1220
5 mil
3.0 6.0
7.5 mil
10 mil
2.5 10
15
15 mil
20
29
40
20 mil
40 mil
45
*
55 mil
*Minimum distance determined by symbol length and scan angle
0 0
5 12.7
10 25.4
15.59 39.6
5 12.7
10 25.4
In. cm
W
i
d
t
h
o
f
F
i
e
l
d
Depth of Field
Note: Typical performance at 68 ∞ F (20 ∞ C)
on high quality symbols.
2.0
40
101.6
45
114.3
15.59 39.6