Conformal Coating Inspection

Conformal coating is always required when electronic printed circuit boards (PCBA) are used in products that perform safety-related tasks or are used in harsh environments. This applies, for example, to automotive applications, defense technology, aerospace, marine, lighting, and industrial applications, as well as to the Green Energy sector. The fluorescent coating, which can be applied by spraying or dipping, protects against environmental influences such as moisture, dirt, dust, condensation, and temperature differences.

As a result of miniaturisation, components have become more densly packed. The insulating effect of the protective coating allows designers to reduce the distance between PCB traces. Automated optical inspection of the protective coating (Conformal Coating Inspection - CCI) helps to ensure the quality of coated PCBA. The presence and quantity of the coating is checked according to the specifications of a coating plan.

Multi Line CCI — Multi Line as CCI system for conformal coating inspection

color camera

telecentric optics
44 x 44 mm field of view

UV
Illumination
Top UV + white
Side UV + red

Multi Line CCI features a high-resolution color camera with telecentric optics for highly detailed images. In combination with UV (ultraviolet) illumination from above and from the side, high-contrast images are generated. The UV illumination causes the fluorescent particles in the coating to glow, revealing defects such as scratches and bubbles. Above all, however, this inspection also reveals whether there is too much or too little coating on the respective assembly.

Multi Line CCI can inspect conformal coatings either from above or below. Simultaneous double-sided inspection is also possible.

In addition, conveyors can be routed underneath the system.

Double-sided inspection with Multi Line CCI

The generation of a test program for conformal coating inspection takes only a few minutes. The areas to be inspected are defined on the basis of CAD data and the coating plan of a PCBA.
The user can choose between an inspection of the coating of pads and pins or an inspection of the entire coated and uncoated areas. Depending on the application, either CAD data or the coating plan is imported.