By an automated camera system all components will be checked on presence and soldering quality.
Non presence of certain components does not necessarily effect the primary function of a PCB.
Certain defects can therefor only be disclosed by this test.
First there is the Optical Inspection where it is made sure that all components are rightly place. This can either be a visual inspection or automated through a so called AOI scanner. AOI refers to Automated Optical Inspection.
Thirdly we perform a Functional Test by which we make sure the print functions as it should. This can be done via connectors or via a pin bed device which makes contact to dedicated contact points on the backside of the PCB.