Omron V530-R150E-2 Operation Manual page 213

Improving Reading
Lighting
Try the following countermeasure when performing reading for a
code created by direct marking on stainless steel.
Countermeasure
Before countermeasure
Ring lighting
Improve reading accuracy by using the optimum lighting for the
reading object.
Section
After countermeasure
Coaxial lighting
9-1
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