Display device and driving method thereof

• US 9,557,839 B2
• Filed: 11/09/2011
• Issued: 01/31/2017
• Est. Priority Date: 07/08/2011
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Cho, Se Hyoung, Ki, Dong-Hyeon, Kim, Dong Gyu
• Primary Examiner(s): Kumar, Srilakshmi K
• Assistant Examiner(s): Adams, Carl
• Application Number:
  US13/292,224
• Publication Number:
  US 20130009930A1
• Time in Patent Office: 1,910 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G09G 2230/00 Details of flat display driving waveforms
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0465 Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness
• CPC Class Codes: G09G 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/0245 Clearing or presetting the whole screen independently of waveforms, e.g. on power-on G09G2310/063 takes precedence
• CPC Class Codes: G09G 2370/24 Keyboard-Video-Mouse [KVM] switch
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

The embodiments of the present invention relate to a display device and a driving method thereof, wherein the display device according to an exemplary embodiment of the present invention includes a plurality of pixels a voltage transmitting line transmitting a first voltage to a first pixel among the plurality of pixels, a data line transmitting a data voltage to the first pixel, and a plurality of sensing units including a first sensing unit connected to the voltage transmitting line, wherein the first pixel includes a first switching element including an input terminal connected to the voltage transmitting line and a second switching element including an input terminal connected to the data line, and the first sensing unit includes a control switching element including an input terminal connected to the voltage transmitting line.

Claims

1. A display device comprising:

a plurality of pixels;

a voltage transmitting line through which a first voltage is transmitted to a first pixel among the plurality of pixels;

a data line through which a data voltage is transmitted to the first pixel;

a plurality of sensing units including a first sensing unit connected to the voltage transmitting line; and

a gate line;

a reset signal line through which a reset signal is transmitted to the first sensing unit;

a sensing signal line to which a sensing signal is output from the first sensing unit; and

a reference capacitor connected to a sensing capacitor,

wherein the first pixel includes a first switching element including an input terminal connected to the voltage transmitting line and a second switching element including an input terminal connected to the data line,

wherein the first sensing unit includes a control switching element including an input terminal connected to the voltage transmitting line,

wherein the first sensing unit includes;

a sensing element and the sensing capacitor both connected to a control terminal of the control switching element; and

a sensing switching element connected to an output terminal of the control switching element,

wherein a control terminal of the sensing element is connected to the gate line, an input terminal of the sensing element is connected to the reset signal line, and an output terminal of the sensing switching element is connected to the sensing signal line, and

wherein the reset signal includes a reset high voltage and a reset low voltage that is lower than the reset high voltage, and wherein the reset high voltage is transmitted through the reset signal line when a gate-on voltage is transmitted through the gate line.

2. The display device of claim 1, further comprising:

a sensing signal processor connected to the sensing signal line wherein the sensing signal processor processes the sensing signal and generates a sensing output signal.

3. The display device of claim 2, wherein the first sensing unit is positioned between the first pixel and a second pixel adjacent to the first pixel in a row direction.

4. The display device of claim 3, wherein the plurality of sensing units are arranged so that one sensing unit is disposed for every two pixel rows in a column direction, and wherein the first sensing unit is adjacent to both the first pixel and a third pixel, wherein the third pixel is adjacent to the first pixel in the column direction.

5. A display device, comprising:

a plurality of pixels for displaying images;

a voltage transmitting line through which a first voltage e is transmitted to a first pixel among the plurality of pixels, the first pixel displaying an image for an input image signal;

a gate line transmitting a gate signal;

a data line through which a data voltage is transmitted to the first pixel;

a plurality of sensing units including a first sensing unit connected to the voltage transmitting line,

wherein the first pixel includes a first switching element including an input terminal connected to the voltage transmitting line and a second switching element including an input terminal connected to the data line,

wherein the first sensing unit includes a control switching element including an input terminal connected to the voltage transmitting line,

wherein a control terminal of the first switching element and a control terminal of the second switching element are commonly connected to the same gate line,

wherein the first voltage is a driving voltage,

wherein the first voltage and a second voltage different from the first voltage are alternately transmitted to the first pixel every at least one frame;

a sensing signal line to which a sensing signal is output from the sensing unit; and

a sensing signal processor connected to the sensing signal line wherein the sensing signal processor processes the sensing signal and generates a sensing output signal, wherein the sensing signal processor includes

an integrator integrating the sensing signal, and

a switch resetting the integrator after a voltage transmitted through the voltage transmitting line is changed from the first voltage to the second voltage or from the second voltage to the first voltage.

6. The display device of claim 5, wherein

the first sensing unit includes

a sensing element connected to a control terminal of the control switching element,

a sensing switching element connected to an output terminal of the control switching element,

a sensing capacitor connected to the control terminal of the control switching element, and

a reference capacitor connected to the sensing capacitor, wherein the reference capacitor is connected to the voltage transmitting line.

7. The display device of claim 5, wherein

the first sensing unit includes

a sensing element connected to a control terminal of the control switching element,

a sensing switching element connected to an output terminal of the control switching element,

a sensing capacitor connected to the control terminal of the control switching element, and

a reference capacitor connected to the sensing capacitor, wherein the reference capacitor is connected to a storage electrode line to which a common voltage is applied.

8. A driving method of a display device comprising a plurality of pixels, a plurality of gate lines including first and second gate lines, a reset signal line, a sensing signal line, a voltage transmitting line and a data line connected to a first pixel among the plurality of pixels, and a plurality of sensing units each connected to the voltage transmitting line and the first and second gate lines, wherein a sensing unit of the plurality of sensing units includes a sensing element connected to the second gate line and the reset signal line, a control switching element connected to the sensing element and the voltage transmitting line, and a sensing switching element connected to the control switching element and the sensing signal line, the method comprising:

transmitting a reset high voltage of a reset signal through the reset signal line to a control terminal of the control switching element;

sensing light irradiated to the sensing element; and

turning on the sensing switching element to transmit a sensing signal to the sensing signal line.

9. The driving method of claim 8, wherein transmitting the reset high voltage of the reset signal to the control terminal of the control switching element includes,

transmitting a gate-on voltage to the second gate line, and

transmitting the reset high voltage to the reset signal line.

10. The driving method of claim 9, wherein sensing the light includes transmitting a gate-off voltage to the first and second gate lines.

11. The driving method of claim 10, wherein transmitting the sensing signal to the sensing signal line further includes transmitting the gate-on voltage to the first gate line, and wherein the sensing switching element is turned on according to the gate-on voltage transmitted to the first gate line.

12. The driving method of claim 11, wherein the first pixel further includes a liquid crystal capacitor, wherein the liquid crystal capacitor includes a first pixel electrode connected to a first switching element connected to the voltage transmitting line, a second pixel electrode connected to a second switching element connected to the data line, and a liquid crystal layer.

13. The driving method of claim 12, further comprising

alternately transmitting a first voltage and a second voltage that is smaller than the first voltage to the first pixel through the voltage transmitting line every at least one frame.

14. The driving method of claim 13, wherein the display device further includes a sensing signal processor, wherein the sensing signal processor processes the sensing signal of the sensing unit and generates a sensing output signal, and wherein the sensing output signal is reset after a voltage transmitted through the voltage transmitting line is changed.