Symbol Technologies DS 3408 User Manual

Page of 396
Scanning
2-9
Decode Zones
Near Focus
Figure 2-7.  DS 3408 Near Focus Decode Zone
In.
cm
0
20 mil
Depth of Field
9.5
2
4
6
8
10
0
5.1
10.2
15.2
20.3
25.4
13 mil (100% UPC)
6.0
5 mil
0.8
7.3
2.0
5.5
15 mil PDF417
0
      cm
W
i
d
t
h
o
f
F
i
e
l
d
0
1.75 4.4
3.5
8.9
8.9
*
*
* Minimum distance determined by symbol length and scan angle.
1.75
3.5
4.4
      in.
Note:  Typical performance at 73˚F (23˚C) 
           on high quality symbols in normal room light.
           Vcc = 3.3V
7.5 mil
1.3
6.3
6.67 mil PDF417
2.3
4.5
10 mil PDF417
1.8
5.8
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