Cross-Shaped Alignment Marks for FPCB and Control PCB Coupling

The patent extends the alignment mark from a single point or simple line (0D/1D) to a cross-shaped structure that spans multiple dimensions across the FPCB and control board. This cross-shaped align mark extends in multiple directions (horizontal and vertical) to provide reference points in different dimensional orientations, enabling precise alignment even as signal line complexity increases.

The alignment mark is divided into multiple segments or extension lines that are distributed at different positions on the FPCB and control board. By segmenting the alignment reference into multiple discrete extension lines rather than using a single continuous mark, the system can maintain alignment precision while accommodating the increased complexity and narrower pitches of modern signal lines.

The cross-shaped align mark acts as an intermediary reference element between the FPCB and the control board. This intermediary alignment structure provides stable, easily identifiable reference points that mediate the alignment process, ensuring precise coupling even when the underlying signal lines become more complex and densely packed.

The alignment mark is formed in advance on both the FPCB and the control board before the actual coupling process. By performing this preliminary alignment preparation, the system establishes precise reference relationships beforehand, which then guide the final coupling operation and prevent misalignment issues that would otherwise arise from the complex signal line configurations.