Panasonic Micro-Imagechecker PV310, Use Manual

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Settin
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If inspection mode = “Gray Range”
Process description Process image
Creates rectangular areas (, which are called
cells) of any size within the inspection area and
calculates the brightness of each area (average
gray value).
Groups the cells and calculates the maximum
grayscale difference in the brightness of the
grouped cell by shifting the grouped cell by the
setting value set for “the number of cells per
shift”. If the calculated maximum grayscale
difference is more than the threshold, the
grouped cell is regarded as a candidate flaw.
The number of grouped cells
The cells are grouped according to the setting
value for “Num. Of Cells for Calc. Range”. If the
setting value for “Num. Of Cells for Calc. Range”
is “4”, four cells are grouped (see the figures
shown on the right).
The number of (skipped) cells per shift
To group the cells aligned from the start point to
the end point in the area, set a value for “Num. Of
Cells per Shift”.
If the setting value for “the number of cells per
shift” is “2”, the PV310 calculates the maximum
grayscale difference for each grouped cell by
skipping two cells until it ends by finally
calculating the rest of the cells in the inspection
area.
Threshold
As you increase the threshold value, the PV310
regards the areas having larger difference in
brightness as a candidate flaw, whereas as you
decrease the threshold value, the PV310 regards
even an area having slight difference in
brightness as a candidate flaw.
The PV310 judges whether the candidate flaw is
regarded as a flaw based on the number of the
cells in the candidate flaw or not. If the number of
cells in the candidate flaw is more than the
number of cells that have been set as “Flaw
Size”, the PV310 judges the cells as a flaw.