Omron V530-R150E-2 Operation Manual page 212

Improving Reading
Before countermeasure
Direct Marking (White Code on Black Background)
Try the following countermeasures for codes created using
direct marking.
Countermeasures
200
The influence of hollowing can be decreased by adjusting the
BGS levels.
Use the smoothing function. For Data Matrix reading in Normal
mode, turn ON Image Adjust (DM)/Filtering Retry , and set
Read DM (Normal)/Background Cut to medium or strong.
Increase the lower limit of the BGS level (making the back-
ground uniformly black).
Section
After countermeasure
9-1