Optical Inspections

Automatic Paste Inspection (API)

After the paste print, an automatic paste inspection takes place on EKRA E5. It makes it possible to identify printing errors, such as missing paste or blurred paste printing already before the placement is accomplished and if necessary, it sorts them out.

Automated Optical Inspection (AOI)

With our LaserVision 6 of Schneider & Koch, automated optical inspection is performed optionally after assembling and soldering.

The following is checked:

• The presence of the components
• Polarity and position of the components
• Correct lettering of the component
• Solder joint by valuating the solder amount
• Short circuit between component pins

During the AOI test, images of each component are captured and stored in a database with the serial number. These images are archived, hence it is always possible to apply the test program with modified test criteria to the entire image dataset of an assembly, even though the modules are no longer in the house.

Manual Optical Inspection (MOI)

For additional manual optical inspection, qualified staff and six stereo microscopes (TS3 and LYNX6/10 of Vision Engineering) are at our disposal. The equipment is complemented by an object comparator. If this is not already been done by the AOI, the following will be checked in the manual optical inspection:

• Assembly of the first module of a batch on the basis of customer specifications
• Check of SMD placement prior to reflow soldering
• Check of THT assembly prior to wave soldering
• Optical inspection of SMD and THT assembly by using the object comparator
• Optical inspection of SMD and THT solder joints with the stereomicroscope

BGA Inspection

For specific components such as BGA and CSP, we offer inspection using our small-gap endoscope "Ersaskope" of ERSA. This allows a precise statement of the solderability. Please note that next to the BGA component about 5mm space is required so that the camera finger and the lighting can reach the circuit board. This way the following questions can be answered:

• Are the BGA solder joints melted?
• Are there any short circuits between the balls?
• Did the solder jump on the ball?