VI User Manual - 第217页
Tools library Vision 2007 4.10 User Manua l Rev 01 7 - 55 7.9.4 Expert mode If all defects are not detected with tolerance s algorithm, 3 Global adjustment tool algorithms are proposed to detect lifted lead s: Peak thr…
Tools library
7 - 54 Vision 2007 4.10 User Manual Rev 01
Lead to lead
Global adjustment tool tolerances are broad to accept all production variations.
In the case above, the
Global adjustment tool can not detect lifted lead.
Lead to lead tolerances are tighter (adapted to average) to detect lead default.
Lead to Lead defaults are showed by an ellipse.
Profiler
™
in Custom
Tools library
Vision 2007 4.10 User Manual Rev 01 7 - 55
7.9.4 Expert mode
If all defects are not detected with tolerances algorithm, 3 Global adjustment tool algorithms
are proposed to detect lifted leads:
Peak threshold,
Contrast,
3D analysis.
You can use one or several algorithm. The choice depends of the position and the orientation
of the profile and of the image you obtain.
Expert mode is used when:
Size of lead of component are irregular,
Difficile case, where tolerances algorithm not detect bad leads,
...
For each
Global adjustment tool algorithm selected, the Lead to lead algorithm must be set.
7.9.4.1 Peak threshold
This algorithm can be use:
When you have a difference of lead length between bad and good lead,
When you have a difference of contrast between bad and good lead,
When you have a difference on joint aspect between bad and good lead.
Principle
This algorithm mea-
sures the
length
of
the profile between
2 points which are
determined by the
intersection be-
tween the profile
and a threshold
straight.
Limits are used
to ignore a part of
the profile.
Threshold (in grey level)
Y max
Length
Ignored
part
Ignored
part
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in Custom
Tools library
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Concrete case
1. Go in Expert tab.
2. In Peak threshold (level of gray) area enter the threshold value to apply and the
peak to use (Y max or Y min).
3. Fill Limits field to ignore a part of the profile.
4. Define the acceptable limits (Length [µm] field).
In this case, for a lifted lead, result of
Peak threshold al-
gorithm is smaller compared with a joined leads.
Profiler
™
in Custom