Apple Inc.
Trace transfer techniques for touch sensor panels with flex circuits

Abstract:

Trace transfer techniques can be used to couple touch electrodes to touch sensing circuitry with a reduced border region around a touch sensor panel. Touch electrodes on a first side of the substrate can be routed to a bond pad region on the second side of the substrate via a trace transfer technique to enable single-sided bonding of a double-sided touch sensor panel. Trace transfer techniques can also be used to couple conductive traces on a first side of the substrate to a flex circuit oriented perpendicular to or otherwise not parallel to the first side of the substrate. Orienting the flex circuit in this way can allow the flex circuit to connect to touch circuitry with reduced bending as compared with the amount of bending of the flex circuit when oriented substantially parallel to the substrate.