Thin-Film Backlit Keyboard Layout for Anti-Ghosting and Low Thickness

The patent combines the light-emitting function and anti-ghosting circuit function into a single integrated thin-film structure. The light-emitting members are positioned on one side of the thin-film circuit unit while the anti-ghosting circuit is formed on the opposite side, allowing both functions to coexist in the same spatial footprint without requiring separate stacked modules, thereby achieving backlighting without significant thickness increase

The patent transitions from a conventional vertical stacking approach to a planar integration approach by forming the anti-ghosting circuit on the backside of the thin-film substrate. This dimensional reorganization allows the light-emitting members and anti-ghosting circuit to occupy different spatial planes while maintaining overall thinness, resolving the contradiction between providing backlighting and maintaining thin profile

The patent employs a thin-film circuit unit with flexible printed circuit board technology, where the anti-ghosting circuit is formed as thin conductive traces on the substrate. This thin-film approach maintains the electrical functionality and anti-ghosting capabilities while reducing the circuit thickness from conventional standards to a minimal profile that does not compromise overall keyboard thinness

The patent replaces conventional mechanical anti-ghosting structures with electrical field-based detection. Instead of relying on mechanical switches or physical contact mechanisms that require significant thickness, the invention uses conductive traces and electrical signals to detect key presses, enabling anti-ghosting functionality through electrical rather than mechanical means, thereby achieving thin-profile design