FlexiblePrintedCircuit (FPC), also known as soft circuit board or flexible circuit board, is highly favored for its excellent characteristics such as light weight, thin thickness, and the ability to be freely bent and folded... However, in China, the quality inspection of FPC still mainly relies on manual visual inspection, which is costly and inefficient. With the rapid development of the electronics industry, circuit board design is increasingly tending towards high precision and high density. Traditional manual inspection methods can no longer meet production demands, and FPC defect automated detection has become an inevitable trend in industrial development.

Flexible circuit (FPC) is a technology developed by the United States in the 1970s for the advancement of aerospace rocket technology. It is a printed circuit with high reliability and excellent flexibility, made of polyester film or polyimide as the base material. By embedding circuit designs on flexible and thin plastic sheets, a large number of precision components can be stacked in narrow and limited Spaces. Thus, a flexible circuit that can be bent is formed. This kind of circuit can be bent and folded at will, is lightweight, small in size, has good heat dissipation and is easy to install, breaking through the traditional interconnection technology. In the structure of flexible circuits, the constituent materials are insulating films, conductors and adhesives.