Patent ID: 8717308

Claim:
A display device comprising: a plurality of first sensing units, each first sensing unit comprising a plurality of first optical sensors connected in series to each other, each first sensing unit comprising a respective first terminal which is coupled to receive a first voltage and to apply the first voltage to a corresponding first end of the series of first optical sensors, the respective first optical sensors of each first sensing unit being distributively disposed along a line extending in a first direction, each first sensing unit comprising a respective second terminal coupled to a respective second end of the series of first optical sensors; a plurality of second sensing units, each second sensing unit comprising a plurality of second optical sensors connected in series to each other, each second sensing unit comprising a respective first terminal which is coupled to receive a second voltage and to apply the second voltage to a corresponding first end of the series of second optical sensors, the respective second optical sensors of each second sensing unit being distributively disposed along a line extending in a second direction transverse to the first direction, each second sensing unit comprising a respective second terminal coupled to a respective second end of the series of second optical sensors; the transverse pluralities of series of the first and second optical sensors defining a matrix; a reset unit operatively coupled to the respective second terminals of each of the first and second sensing units and structured to apply a predetermined reset voltage to the respective second terminals of each of the first and second sensing units; and a read-out unit operatively coupled to the respective second terminals of each of the first and second sensing units and structured to sense a light obstructing touch position within the matrix based on voltage differences at the second terminals of the first and second sensing units relative to the predetermined reset voltage.