Using a microscope to inspect the solder wettability of mounting components

A printed circuit board with mounted components

Application - Assessing the quality of electronic components mounted to a printed circuit board

After electronic components are mounted on a printed circuit board, they are visually inspected to determine whether they are mounted properly. In the past, the boards were photographed using a CCD camera to check the condition of the mounting. One problem with this method is that light from the camera can reflect off the solder, making it difficult to capture clear images of the mounted components. To compensate, inspectors adjust the illumination for each board being photographed, but this is difficult to do without any human error.

Due to the issues with the camera, visual inspection using a microscope is also necessary to help ensure the quality of the final product. However, even an inspection using a microscope can be difficult due to halation caused by solder.

A Solution for getting images with minimal halation

The Olympus BX53M industrial microscope offers simultaneous brightfield and darkfield illumination to capture images without halation, and OLYMPUS Stream image analysis software has advanced image functionality.

Inspecting the leads of mounted components

The BX53M microscope offers MIX illumination, which enables you to combine darkfield with brightfield illumination, simple polarization illumination, or fluorescent illumination. Using MIX illumination with OLYMPUS Stream software, halation can be effectively eliminated. With no halation, it is much easier to inspect the leads of mounted components that were soldered.

Images

A microscope image captured using darkfield illumination

A microscope image captured using simultaneous brightfield and darkfield MIX illumination