DEFECT PROPORTION OF DETECTION INITIAL RATE DETECTION RATE INSPECTOR 3
COMPLEXITY OF TIMES PAN OF PERFORMING o
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______________________ __ -;. INSPECTION TASK
-;. VISUAL INSPECTION Fagure 1. Trends in relations between the
complexity of inspection tasks, defect detection rates (absolute and
relative), and inspection time. Irrespective of the necessities
described above, and with the excep- tion of specific generic
application systems (e.g., bare-board PCB inspection, wafer inspection,
solder joint inspection, linewidth measure- ment), vision systems are
still not found frequently in today's electronics factories. Besides
cost, some major reasons for this absence are: 1. The detection
robustness or accuracy is still insufficient. 2. The total inspection
time is often too high, although this can frequently be attributed to
mechanical handling or sensing. 3. There are persistent gaps among
process engineers, CAD en- gineers, manufacturing engineers, test
specialists, and computer vision specialists, as problems dominate the
day-to-day interac- tions and prevent the establishment of trust. 4.
Computer vision specialists sometimes still believe that their
contributions are universal, so that adaptation to each real problem
becomes tedious, or stumbles over the insufficient availabIlity of
multidisciplinary expertise. Whether we like it or not, we must still
use appropriate sensors, lighting, and combina- tions of algorithms for
each class of applications; likewise, we cannot design mechanical
handling, illumination, and sensing in isolation from each other.