Konica Minolta Darwin VDP Software - Manual (Page 11)

Page 11 of 92
T EC - I T B a r c o d e So f t w a re R e f e re n c e
Figure 6: Raster Optimization
4.2.3 Module Width and Reading Distance
The actual reading distance for barcodes depends on two factors: the scanner hardware and the
module width of the barcode.
There is no scanner, which can read all barcodes (ranging from high density codes to barcodes with
wide tracking) from all distances. Each barcode scanner has an optimum reading distance for bar-
codes with a certain module width. The correlation between the module width and the reading
distance is usually specified by the manufacturer of the barcode scanner. The following table shows
such an exemplary specification.
Thus, depending on the module width the optimum reading distance for a specific scanner can be
identified. On the other hand, if the reading distance is given by the application, the required module
width for printing the barcodes may be adjusted.
Module Width
(1 mil = 1/1000 mm)
Depth of Field
(Reading Distance)
5 mil 7.6 to 15.2 cm / 3 to 6”
7.5 mil 5.1 to 40.6 cm / 2 to 16“
10 mil 3.8 to 55.9 cm / 1.5 to 22”
13 mil 2.5 to 76.2 cm / 1 to 30”
20 mil 2.5 to 106.7 cm / 1 to 42”
55 mil 5.1 to 203.2 cm / 2 to 80”
Table 2: Example for Scanner Specification
4.3 Quiet Zone
A quiet zone (an area free of any printing or marks) should be maintained directly before and after
the barcode symbol. The quiet zone helps the scanner to determine the barcode correctly.
As a rule, the quiet zone should be ten times the dimension of the module width or at least 1/4 inch
(6.5 mm); the exact value depends on the barcode symbology.