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Review of Camera Performance and Features
Examples of color artifacts generated by a small encoder error:
Figure 9: Color Artifacts Example (encoder 19 µm)
Image Details:
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Object Pixel Setup for 20 µm
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Encoder set at 19 µm
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Forward Scanning
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Can be corrected with 20 / 19 = 1.05 Spatial Correction
Figure 10: Color Artifacts Example (encoder 21µm)
Image Details:
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Object Pixel Setup for 20 µm
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Encoder set at 21 µm
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Forward Scanning
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Can be corrected with 20 / 21 = 0.95 Spatial Correction
If there are several different camera angles and associated illumination configurations in the
inspection system, a single encoder pulse will not provide the correct timing for all the cameras.
For example, as the camera angle moves away from perpendicular, the image row spacing
increases. If the encoder resolution remains at that for perpendicular operation, many encoder
pulses will be too closely spaced, apparent row spacing will increase and the spatial correction will
need to be increased.
The spatial correction feature can accommodate these potentially larger encoder errors where the
spatial correction value has an adjustment range from 0 to 15.99.
