Omron V460-H User Manual page 30

1-3-2 Code Readability Tables
The readability tables below are designed to help you choose the best distance to read their particular code size
and code type successfully. The tables show the calculated PPE (Pixels Per Element) for a range of typical code
sizes at certain focus distances.
PPE is defined as the following for 1D and 2D codes:
• PPE for 1D codes is the number of pixels across the thinnest bar in the barcode.
• PPE for 2D codes is the number of pixels across a single code cell.
The tables show a color code for readability based on labels and Direct Part Marks (DPM) where red means not
likely to read, and green means that it should read. The tables also show a range of colors between red and
green, while showing the zone where read rates may be acceptable for high-contrast, well-printed labels and can
be considered.
1D Code Readability Guidelines
 High-Contrast Labels
• 1.5 pixels per thin bar is suggested minimum;
• 2 pixels or more per thin bar is preferred.
 Direct Part Marks
• 2 pixels per thin bar is suggested minimum;
• 2.5 pixels or more per thin bar is preferred.
2D Code Readability Guidelines
 High-Contrast Labels
• 2.5 – 2.75 pixels per 2D cell is suggested minimum;
• 3.5 – 5 pixels per 2D cell is preferred.
 Direct Part Marks
• 3.25 pixels per 2D cell is suggested minimum;
• 4 – 6 pixels per 2D cell is preferred.
1D Label Readability Table
Additional readability tables on next page.
V460-H Industrial Handheld DPM Reader User Manual
1 Product Overview
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