DISPLAY DEVICE

• US 20110080391A1
• Filed: 04/28/2009
• Published: 04/07/2011
• Est. Priority Date: 06/03/2008
• Status: Abandoned Application

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Brown, Christopher, Katoh, Hiromi
• Application Number:
  US12/995,853
• Publication Number:
  US 20110080391A1
• Time in Patent Office: Days
• US Class Current: 345/207
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/042 by opto-electronic means

Abstract

A display device includes a photosensor in a pixel region (1) of an active matrix substrate (100). The photosensor is provided with a photodetection element (D1) that receives incident light; a capacitor (C2), one electrode of which is connected to the photodetection element (D1), that accumulates output current from the photodetection element (D1); reset signal wiring (RST) that supplies a reset signal to the photosensor; readout signal wiring (RWS) that supplies a readout signal to the photosensor; and a sensor switching element (M2) that, in accordance with the readout signal, reads out the output current accumulated in the capacitor (C2) from when the reset signal is supplied until when the readout signal is supplied. Conductive wiring (ML) is provided along readout wiring (SLr) that is for reading out the output current, the conductive wiring (ML) being connected to neither the photodetection element (D1) in the pixel region nor a pixel switching element (M1) of the pixel region.

Claims

1. A display device comprising a photosensor in a pixel region of an active matrix substrate, the photosensor being provided with:

a photodetection element that receives incident light;

a capacitor, one electrode of which is connected to the photodetection element, that accumulates output current from the photodetection element;

reset signal wiring that supplies a reset signal to the photosensor;

readout signal wiring that supplies a readout signal to the photosensor; and

a sensor switching element that, in accordance with the readout signal, reads out the output current accumulated in the capacitor from when the reset signal is supplied until when the readout signal is supplied, wherein conductive wiring is provided along readout wiring that is for reading out the output current, the conductive wiring being connected to neither the photodetection element in the pixel region nor a pixel switching element of the pixel region.

2. The display device according to claim 1, wherein a unity-gain amplifier that causes a potential of the conductive wiring to be the same as a potential of the readout wiring is connected to the conductive wiring.

3. The display device according to claim 1, wherein an amplifier having a gain greater than I in order to cause a potential of the conductive wiring to be the same as a potential of the readout wiring is connected to the conductive wiring.

4. The display device according to claim 1, wherein the readout wiring also serves as a source line that supplies an image signal to the pixel switching element of the pixel region.

5. The display device according to claim 1, wherein the sensor switching element is an amorphous silicon TFT or a microcrystalline silicon TFT.

6. The display device according to claim 1, wherein the photodetection element is a phototransistor.

7. The display device according to claim 6, wherein the photodetection element is an amorphous silicon TFT or a microcrystalline silicon TFT.

8. The display device according to claim 6, wherein a gate and a source of the photodetection element are connected to the reset signal wiring.

9. The display device according to claim 6, wherein the reset signal wiring is connected to a gate of the photodetection element, and second reset signal wiring that causes a potential drop after the photodetection element has entered an off state is connected to a source of the photodetection element.

10. The display device according to claim 1, further comprising:

a common substrate opposing the active matrix substrate; and

liquid crystal sandwiched between the active matrix substrate and the common substrate.