Siemens SIMATIC MV500, Operating Instructions Manual, Page: 59 / 294

Image processing
3.2 Code verification
SIMATIC MV500
Operating Instructions, 03/2021, C79000-G8976-C494-05
59
3.2.5.4 AS9132 Rev. A
This standard first appeared as a data matrix standard of the IAQG (International Aerospace
Quality Group).
This standard applies directly to three specific types of marking:
•
Dot peen markings
• Laser marking
• Electrochemical etched markings
The optical readers of the SIMATIC MV540 series focus on the quality criteria of dot peen
markings that are the most frequently used. Module fill and contrast are calculated as a
reference but are not included in the overall grading.
Quality features of the dot peen marking
• Angle of distortion: Difference between the two solid edges of the data matrix and the
vertical edges measured in degrees.
• Module center offset:
Linear deviation of the location of the center point of the cell compared with the center of
the ideal grid calculated as a percentage of the nominal cell size.
• Module size offset:
Difference in the apparent size of each individual data element in the data matrix.
• Module fill:
Measurement of the completeness of the ideal grid as a percentage.
• Nominal module size:
Average value of the two values nominal module size X and nominal module size Y.
– Nominal module size X: Width of the data matrix code in pixels divided by the number
of columns.
– Nominal module size Y: Height of the data matrix code in pixels divided by the number
of rows.
• Ovality:
Difference between the widest part of the round cell and the narrowest part of the round
cell.
• Contrast:
Difference between the average reflectance of the lightest pixels and the darkest pixels.
Calculated only as a reference
Note
Support for advanced quality features
No expanded quality parameters are used for laser marking and electrochemical etched
marking.