Foldable Touch Display Device Bending Area Thickness Reduction

The patent extracts the flexible circuit board wires from the bending area and replaces them with rigid electrode lines directly formed on the touch sensing film. This removal of unnecessary flexible wiring components reduces the overall thickness while maintaining foldability through the flexible substrate itself.

The patent applies different line widths to electrode lines in different regions: wider lines in the bending area to reduce impedance and maintain electrical performance, and narrower lines in non-bending areas to minimize thickness. This local differentiation resolves the contradiction between electrical performance and thinness.

By removing the flexible circuit board wires from the bending area and using only the essential electrode lines with varying widths, the patent reduces the volume of material in the bending zone, enabling a smaller radius of curvature and tighter folding.

The patent changes the physical parameters of the electrode lines by varying their width along the bending area. This parameter modification allows the structure to accommodate tighter curvature while maintaining electrical conductivity, achieving both small radius of curvature and functional performance.

The patent implements a systematic parameter change approach where electrode line width varies continuously or in steps along the bending area. This can be achieved through photomask design or direct writing techniques, making the manufacturing process manageable despite the varying dimensions.

The patent applies local quality by specifying different line widths only in the bending area where curvature is needed, while keeping other areas uniform. This localized approach minimizes manufacturing complexity by limiting the varying parameter application to only where it is functionally necessary.