US 8,553,013 B2Granted

Liquid crystal display device having touch sensor embedded therein, method for driving the same, and method for fabricating the same

AssigneeLG Display Co., Ltd.

InventorCheol-Se Kim

Life of this patent

Estimating the term…

Loading patent…

Abstract

Disclosed is a liquid crystal display device having touch sensors embedded therein. The liquid crystal display device includes a liquid crystal layer interposed between upper and lower substrates, pixels, each of which includes pixel and common electrodes applying a horizontal electric field to the liquid crystal layer, a pixel thin film transistor to drive the pixel electrode, and a common thin film transistor to drive the common electrode, touch sensors, each of which forms a sensing capacitor between an object and the common electrode, sensor power lines, readout lines, and sensor gate lines. Each touch sensor includes the common electrode, a first sensor thin film transistor charging the common electrode with the sensing driving voltage in response to control of the previous sensor gate line, and a second sensor thin film transistor outputting the sensing signal to the readout line in response to control of the current sensor gate line.

Claims19

Dependent claims

A liquid crystal display comprising:

a liquid crystal layer interposed between upper and lower substrates;
a plurality of pixels, respectively formed in pixel regions of the lower substrate, each of the plurality of pixels including a pixel electrode and a common electrode applying a horizontal electric field to the liquid crystal layer, a pixel thin film transistor connected with a gate line and a data line to drive the pixel electrode, and a common thin film transistor connected with the gate line and a common line to drive the common electrode;
touch sensors, each forming a sensing capacitor between an object touching the upper substrate and the common electrode to sense touch and then to output a sensing signal;
sensor power lines to supply sensing driving voltage to the respective touch sensors;
readout lines to output the sensing signal from the respective touch sensors;
and
sensor gate lines formed parallel with gate lines, wherein each of the touch sensors includes:
the common electrode formed in plural pixels;
a first sensor thin film transistor to charge the common electrode with the sensing driving voltage from the corresponding sensor power line in response to control of the previous sensor gate line;
and
a second sensor thin film transistor to output the sensing signal from the common electrode to the corresponding readout line in response to control of the current sensor gate line.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/980,872Filed 29 Dec 2010
Priority: KR 10-2010-007700310 Aug 2010
Published: US 2012/0038585 A116 Feb 2012
Granted: 8 Oct 2013
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

G06F 3/0443
By capacitive means: using a single layer of sensing electrodes
G02F 1/13338
Constructional arrangements; Manufacturing methods: input devices, e.g. touch panels
G06F 3/0412
Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means: digitisers structurally integrated in a display
H10D 86/021
Manufacture or treatment: of multiple TFTs