Patent ID: 8643618

Claim:
A touch display device adapted for use with an electronic stylus capable of radiating an electromagnetic wave signal, said touch display device comprising: a liquid crystal display (LCD) module having a top surface, said top surface being configured with a central display area and a peripheral non-display area surrounding said central display area; and an electromagnetic-type touch input device including a main sensor board disposed under said LCD module for sensing the electromagnetic wave signal from the electronic stylus upon a touching by the electronic stylus so as to generate a first sensing output corresponding to a touch point of the electronic stylus, an auxiliary periphery sensor disposed on said top surface of said LCD module, and including a plurality of X-axis antenna coils and a plurality of Y-axis antenna coils disposed above said peripheral non-display area of said top surface of said LCD module for sensing the electromagnetic wave signal from the electronic stylus upon the touching by the electronic stylus so as to generate a second sensing output corresponding to the touch point of the electronic stylus, and a control unit connected electrically to said main sensor board and said auxiliary periphery sensor for receiving the first and second sensing outputs therefrom, said control unit being operable to output an input signal associated with a two-dimensional coordinate and corresponding to a location of the touch point of the electronic stylus based on the first and second sensing outputs.