Touch sensing apparatus having a multi-turn planar coil inductor and touch screen thereof

1. A display substrate for detecting a touch motion by induction, comprising:

a base substrate;

a black matrix layer on the base substrate defining a plurality of light transmissive regions;

an inductor layer on the base substrate, the inductor layer comprising at least one inductor, each of the at least one inductor having a multi-turn planar coil structure, a projection of the inductor layer on the base substrate substantially overlapping with that of a portion of the black matrix layer;

at least one first sensing circuit coupled to the at least one inductor and configured to be provided with an AC signal and to detect a change of the AC signal induced by the touch motion;

a common electrode layer; and

an insulating layer between the inductor layer and the common electrode layer;

wherein each of the at least one inductor comprises a first terminal and a second terminal, each of the at least one first sensing circuit comprises an output port coupled to the first terminal of a corresponding inductor, the AC signal being provided to the corresponding inductor through the output port, and the second terminal being provided with a common voltage;

each of the at least one first sensing circuit comprises an output port coupled to a first terminal of the at least one inductor and a common voltage terminal coupled to a second terminal of the at least one inductor, the AC signal being provided to the inductor through the output port, and the common voltage terminal and the second terminal are coupled to the common electrode layer; and

the second terminal is coupled to the common electrode layer through a via extending through the insulating layer.

2. The display substrate of claim 1 , wherein a line width of the multi-turn planar coil structure is substantially the same as or smaller than a line width of the black matrix layer.

3. The display substrate of claim 1 , wherein the multi-turn planar coil structure comprises a plurality of substantially parallel adjacent line segments, each two parallel adjacent line segments being spaced apart by no more than two light transmissive regions.

4. The display substrate of claim 1 , wherein the multi-turn planar coil structure comprises a plurality of substantially parallel adjacent line segments, each two parallel adjacent line segments being spaced apart by a single light transmissive region.

5. The display substrate of claim 1 , wherein the multi-turn planar coil structure is selected from a group consisting of a square multi-turn spiral coil, and a rectangular multi-turn spiral coil.

6. The display substrate of claim 1 , wherein each of the at least one first sensing circuit further comprises a common voltage terminal coupled to the second terminal of the corresponding inductor, the common voltage terminal and the second terminal being provided with a common voltage.

7. The display substrate of claim 1 , wherein the at least one inductor comprise a plurality of inductors arranged in a matrix on the base substrate, the at least one first sensing circuit comprises a plurality of first sensing circuits coupled to the plurality of inductors respectively, each of the plurality of first sensing circuits is configured to independently detect the change of the AC signal in one of the plurality of inductors induced by the touch motion.

8. The display substrate of claim 7 , further comprising a data selection circuit configured to receive one or more of changes of AC signals from one or more of the plurality of first sensing circuits, select any one of the one or more of changes of AC signals transmitted from the one or more of the plurality of first sensing circuits as a selected change of the AC signal, and output the selected change of the AC signal.

9. The display substrate of claim 1 , wherein the inductor layer is on a side of the black matrix layer distal to the base substrate.

10. The display substrate of claim 1 , wherein the inductor layer is on a side of the black matrix layer proximal to the base substrate.

11. The display substrate of claim 1 , wherein the inductor layer is on a side of the base substrate distal to the black matrix layer.

12. The display substrate of claim 1 , wherein the base substrate is a base substrate of a color filter substrate in a display panel, each of the plurality of light transmissive regions corresponding to a subpixel region of the display panel.

13. The display substrate of claim 1 , wherein the base substrate is a base substrate of an array substrate in a display panel, each of the plurality of light transmissive regions corresponding to a subpixel region of the display panel.

14. The display substrate of claim 1 , wherein the display substrate is a color filter substrate.

15. A display panel comprising the display substrate of claim 1 .

16. A display apparatus, comprising the display panel of claim 15 .

17. A method of fabricating a display substrate for detecting a touch motion by induction, comprising:

forming a black matrix layer on a base substrate, wherein the black matrix layer is formed to define a plurality of light transmissive regions;

forming an inductor layer comprising at least one inductor on the base substrate, each of the at least one inductor having a multi-turn planar coil structure, a projection of the inductor layer on the base substrate substantially overlapping with that of a portion of the black matrix layer;

forming at least one first sensing circuit coupled to the at least one inductor and configured to be provided with an AC signal and to detect a change of the AC signal induced by the touch motion;

forming a common electrode layer; and

forming an insulating layer between the inductor layer and the common electrode layer;

wherein each of the at least one inductor is formed to comprise a first terminal and a second terminal, each of the at least one first sensing circuit is formed to comprise an output port coupled to the first terminal of a corresponding inductor, the AC signal being provided to the corresponding inductor through the output port, and the second terminal being provided with a common voltage;

each of the at least one first sensing circuit is formed to comprise an output port coupled to a first terminal of the at least one inductor and a common voltage terminal coupled to a second terminal of the at least one inductor, the AC signal being provided to the inductor through the output port, and the common voltage terminal and the second terminal are coupled to the common electrode layer; and

the second terminal is formed to be coupled to the common electrode layer through a via extending through the insulating layer.