Omron V460-H User Manual page 241

4 WebLink Configuration
HH
such as working distance and color of illumination have been evaluated to ensure they are not negatively
impacting optical resolution in the system. When designing an optical setup you should evaluate and
optimize to achieve the best possible modulation transfer function (MTF) for the imager. Poor optical
resolution typically results in a degraded modulation score can have a cascading effect on other metrics.
General Grading Functionality
The Grading Process
Grading evaluation does not take place until a Data Matrix has been identified by the X-Mode decoder.
Once the Data Matrix has been decoded by the X-Mode decoder, a separate grading evaluation begins.
Note that this evaluation can potentially add significant processing time to the overall process, and each
specification requires independent evaluation. Furthermore, enabling any single parameter within a given
specification requires the complete grading evaluation.
Grading – ISO/IEC 16022
Overview
This section outlines the grading implementation of ISO/IEC 16022 available in the reader firmware.
Please refer to the ISO/IEC 16022 standard itself for further information about specifications.
Supported Symbologies
The ISO/IEC 16022 standard defines the symbology requirements for the Data Matrix symbology.
Minimum Resolution
6 pixels per element is the Minimum Resolution.
Symbol Contrast
Symbol Contrast measurements assume that 8-bit 0 – 255 intensity in the captured image correlates
directly to 0 – 100% reflectance. Symbol Contrast is calculated and graded for each scan and provided
for the overall grade calculation in accordance with the ISO/IEC 16022 specification. The parameter
grade and value provided for output is an average of all measured scans across the entire symbol.
Axial Non-Uniformity
Axial Non-Uniformity measures the relationship between the overall dimensions of the two axes of the
symbol. Axial Non-Uniformity is calculated in accordance with the ISO/IEC 16022 specification.
Unused Error Correction
Unused Error Correction measures the remaining error correction available after correcting the errors
within the decoded symbol. It is calculated in accordance with the ISO/IEC 16022 specification.
4-158
V460-H Industrial Handheld DPM Reader User Manual