Panasonic PV-500, User Manual

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Template Rotated by 180d
Use this function when running a test with a
specified Rotation Range setting detects
a180-degree reversed image by mistake, or a
180-degree reversed image is similar to the image
pattern registered as a template.
1.
Select "Inspection Condition".
2
. Select “Yes” for “Template Rotated by
180d”.
Ignore Dark Image
This function is useful to inspect a dark image undesired areas of which are detected.
The function ignores the part that has lower brightness than the set threshold (0 - 255) for the gray values of
the area within a template.
1.
Select "Inspection Condition".
2.
Select “Yes” for “Ignore Dark Image”.
3.
Enter a value of brightness limit in “Threshold to Ignore Dark Image”.
Setting a Sequence
Set a sequence to search an image pattern of a template within a search area.
The checker executes a searching on the compressed information of template and search area. The
compression rate of the information is lowered every time a searching phase (up to six phases) proceeds.
Processing speed is inversely related to compression ratio; the higher compression ratio, the faster processing
speed, the lower compression ratio, the slower processing speed.
Specifying Items in “Sequence”
Step
Inspection is performed in up to six steps (1st - 6th) by changing compression ratio and other conditions.
Accuracy
This is compression ratio. There are seven types of compression ratio; 32.16, 8, 4, 2, 1, and S. Accuracy
16, for example, refers to compressing of information of 16 x16 (256) pixels. The smaller value indicates
the lower compression. Accuracy value must be smaller as a scanning step proceeds.
Accuracy “1” means that searching is performed without compressing the information. Accuracy “S” means
that detection is executed per subpixel. If the accuracy is set to "1" or "S", the steps after that will be erased
and no more steps can be added. (You cannot include both "1" and "S" in one sequence. (e.g. Step
4TH=Accuracy 1, Step 5TH=Accuracy S))
Maximum Count
Maximum number of the part to be detected in each step.
Setting an intermediate step to “3” detects 3 parts with higher correlation value than the minimum value in
descending order, and then inspects the parts with lower compression ratio in the next step. Setting the
final step to “3” judges as “OK” three or more parts are detected, and judges as “NG” if less than three
parts or nothing are/is detected.
Minimum Correlation
In a certain step, the checker detects the parts having the higher correlation value than this setting value. If
there is no image with higher correlation value than it, the inspection stops at the step and judges as "NG".
Squaring Correlation Value
This is a function that squares correlation values to emphasize them. By squaring them, low values
become much lower. Use this function when you want to widen the difference of correlation values
between the object to detect and the object not to be detected.