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the OCV segmentation threshold through the scroll bar and select parameters, so that the image
part to be extracted can be clearly identified, which is beneficial to improve the inspection
stability. This algorithm is generally used for character inspection.
[IC Short Circuit]: this algorithm divides the IC dense solder legs to calculate the number of
IC solder legs and their length and width. This algorithm is generally aimed at short circuit
inspection of IC dense solder legs, as shown in the following figure:
Click the "Short Circuit Setting" button to enter the parameter setting window. The user can
adjust the area threshold and segmentation threshold through the scroll bar and select parameters,
and filter out interference parts, so that the pin parts in the template image can be clearly
identified. The system will automatically identify the number of pins, the maximum pin width
and the average pin width according to the vertical projection of the segmented communication
domain. Under normal circumstances, the maximum pin width should be approximately equal to
the average pin width.
If the maximum pin width is greater than 1.7 time of the average pin width under the same
segmentation conditions during testing, it means that there are pins and their solder widths are
beyond the normal range, which is most likely caused by solder short circuit. At this time, an NG
error will be reported. If the user has checked the pin number test, the system will inspect the pin
number at the same time during the test. If it is inconsistent with the setting, the system will also
report NG error.
If the user's PCB itself has a white background with high brightness, and the traditional
threshold segmentation cannot accurately isolate the solder from the PCB background color, the
user can check the "Whiteboard". At this time, the system will use a specific channel algorithm
to filter out the influence of white and increase the stability of segmentation.
In some cases, there are white silk screens perpendicular to the pins on the PCB under the
pins, which may also affect the pin division. At this time, the user can check "Ignore Long
Straight Line" and open the setting window through the setting button, adjust the parameter
division and set the range of that straight line. During inspection, the image within the range of