Datalogic P2x-Series, Product Reference Manual

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ILLUMINATORS
54
P2X-SERIES™
LIGHTNING
Illuminating the target properly and create contrast between the inspection object and
the features to be detected is crucial for a good quality Machine Vision application.
The control of the lightning is critical for the test reproducibility and the robustness of
the application (e.g .managing sample variation).
The illumination technique depends on the light source, its position and the interaction
with the inspection object and the camera. Dealing with the parameters and selecting
the best option is the result of the analysis of the possible combinations and their
effects.
Lightning Techniques
Backlighting Field Illumination
This technique is commonly used for parts presence/absence, gauging and orientation/
location. The light is oriented behind a transparent object of interest to examine surface
features.
Bright Field Illumination
Lighting of surfaces at high (narrow) angles used to provide maximum reflection of the
light to the camera’s lens. This is effective on surfaces that absorb light or are not highly
reflective and also on low contrast codes.
Coaxial Field Illumination
When the light hits the surface, most of it will reflect away from the lens and produce a
dark image. Coaxial lights hit the surface perpendicular to the object plane providing a
diffuse illumination and reducing shadowing.
Electronic Object
Non polarized Polarized
NOTE
If no polarized illuminator is used, the user may avoid LED reflections by
turning on one or more sectors according to the code position in the
reader’s Field of View.