Photosensitive structure, photosensitive display substrate, and fabrication and control methods of the photosensitive display substrate

Patent metadata

Field	Value
Publication number	US-9939960-B2
Application number	US-201515031004-A
Country	US
Kind code	B2
Filing date	Aug 14, 2015
Priority date	Dec 26, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

The present disclosure provides a photosensitive structure, a photosensitive display substrate, and fabrication and control methods of the photosensitive display substrate. The photosensitive structure includes a first conductive layer; a second conductive layer; and a photoconductive material layer, sandwiched there-between. In response to a light illumination, the photoconductive material layer is capable of changing from an insulating state to a conductive state. One or more first constant voltage sources are configured in a periphery of the first conductive layer to charge the first conductive layer in different directions to maintain a first voltage there-on. Each current measurement unit is disposed between one first constant voltage source and the first conductive layer and configured to measure a charging current between the first constant voltage source and the first conductive layer, and configured to output current signals corresponding to the first constant voltage sources. A touch signal determination unit is connected to the current measurement units to determine a touch position.

First claim

What is claimed is:

1. A photosensitive structure, comprising:
a first conductive layer;
a second conductive layer;
a photoconductive material layer, sandwiched between the first conductive layer and the second conductive layer, wherein:
in response to a light illumination, the photoconductive material layer is capable of changing from an insulating state to a conductive state, and
the photoconductive material layer includes meshes formed by a first plurality of photoconductive material lines and a second plurality of photoconductive material lines that are crossly configured, each mesh corresponding to a pixel cell;

one or more first constant voltage sources, configured in a periphery of the first conductive layer to charge the first conductive layer in a plurality of different directions to maintain a first voltage on the first conductive layer;
a plurality of current measurement units, each disposed between the first constant voltage source and the first conductive layer and each configured to measure a charging current between the first constant voltage source and the first conductive layer, wherein the plurality of current measurement units are configured to output a plurality of current signals corresponding to the one or more first constant voltage sources; and
a touch signal determination unit, connected to the plurality of current measurement units to determine a touch position based on the plurality of current signals from the plurality of current measurement units,
wherein the second conductive layer includes meshes corresponding to the meshes in the photoconductive material layer.

2. The photosensitive structure of claim 1 , wherein the one or more first constant voltage sources are connected to the first conductive layer at different locations of the first conductive layer to supply voltage to the first conductive layer via the different locations.

3. The photosensitive structure of claim 2 , wherein:
the first conductive layer has a polygonal shape, and the different locations of the first conductive layer include different sides and vertexes of the first conductive layer.

4. The photosensitive structure of claim 2 , wherein:
the first conductive layer has a circular shape, and the different locations of the first conductive layer include different location points that are symmetrically-configured or evenly-distributed on the first conductive layer.

5. The photosensitive structure of claim 1 , wherein the first conductive layer comprises a rectangular conductive layer.

6. The photosensitive structure of claim 5 , wherein the one or more first constant voltage sources are configured to apply a same voltage to four corners of the rectangular conductive layer.

7. The photosensitive structure of claim 5 , wherein at least three first constant voltage sources are configured to apply a voltage to four corners of the rectangular conductive layer.

8. The photosensitive structure of claim 5 , wherein the plurality of the current measurement units includes four current measurement units, each connected to one of four corners of the rectangular conductive layer.

9. The photosensitive structure of claim 1 , wherein one first constant voltage source is configured and connected to the plurality of current measurement units.

10. The photosensitive structure of claim 1 , wherein the photoconductive material layer is sheet-shaped or mesh-shaped.

11. The photosensitive structure of claim 1 , wherein, when the first conductive layer has a rectangular shape with four corners A, B, C and D connected to four current measurement units to respectively measure the charging current at each corner denoted as i_A, i_B, i_C and i_D, the touch position of a touch point on the first conductive layer is determined by:

L
⁢

⁢
1

L
⁢

⁢
2

⁢

⁢
and
⁢

⁢

L
⁢

⁢
3

L
⁢

⁢
4

,

wherein:

L
⁢

⁢
1

L
⁢

⁢
2

=

i_A
i_D

=

i_B
i_C

,

⁢

L
⁢

⁢
3

L
⁢

⁢
4

=

i_D
i_C

=

i_A
i_B

,

L1 is a distance between corner A or B and the touch point in a length direction of the rectangular shape,
L2 is a distance between corner C or D and the touch point in a length direction of the rectangular shape,
L3 is a distance between corner A or D and the touch point in a width direction of the rectangular shape, and
L4 is a distance between corner B or C and the touch point in a width direction of the rectangular shape.

12. The photosensitive structure of claim 1 , wherein at least one of the first conductive layer and the second conductive layer is made of a transparent conductive material, the transparent conductive material including indium tin oxide (ITO).

13. The photosensitive structure of claim 1 , wherein:
the photoconductive material layer is made of one or more of an inorganic material and an organic material,
the inorganic material includes selenium, selenium tellurium alloy, cadmium sulfide, zinc oxide, or a combin

Assignees

• Boe Technology Group Co Ltd
• Boe Technology Group Co Ltd

Inventors

• Zhou Xiaodong

Classifications

• G06F3/042 Primary

  by opto-electronic means · CPC title

• G02F1/13338

  Input devices, e.g. touch panels · CPC title

• G02F1/135

  Liquid crystal cells structurally associated with a photoconducting or a ferro-electric layer, the properties of which can be optically or electrically varied {(G02F1/133348 takes precedence)} · CPC title

• G06F3/0421 Primary

  by interrupting or reflecting a light beam, e.g. optical touch-screen · CPC title

• G06F2203/04103

  Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices · CPC title