Electrical touch screen sensor

• US 20080055260A1
• Filed: 08/30/2006
• Published: 03/06/2008
• Est. Priority Date: 08/30/2006
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Posamentier, Joshua
• Granted Patent: US 9,280,238 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• 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 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/044 by capacitive means

Abstract

Apparatus, systems including an electrical touch screen sensor and methods for implementing an electrical touch screen sensor are disclosed. For example, an apparatus is disclosed including a display having an array of display pixels and a plurality of sensors distributed amongst the display pixels and embedded within the display, where the sensors act to detect changes in capacitance associated with objects placed in proximity to the display pixels. Other implementations are also disclosed.

Claims

1. An apparatus comprising:

a display including an array of display pixels; and

a plurality of sensors distributed amongst the display pixels and embedded within the display, the sensors to detect changes in capacitance associated with objects placed in proximity to the display pixels.

2. The apparatus of claim 1, wherein the display pixels comprise a plurality of display pixel regions, wherein the each of the sensors is associated with a corresponding one of the display pixel regions, and wherein two or more of the sensors are at least capable of simultaneously detecting changes in capacitance associated with objects placed in proximity to different display pixel regions of the plurality of display pixel regions.

3. The apparatus of claim 1, wherein each sensor of the plurality of sensors comprises:

a transimpedance amplifier (TIA);

a capacitance detection element (CDE) coupled to the TIA; and

a buffer coupled to the CDE.

4. The apparatus of claim 3, wherein the TIA is to supply a voltage pulse to the CDE, and wherein the buffer is to obtain a voltage profile from the CDE, the voltage profile to correspond to the voltage pulse as modified by capacitive coupling of an object in proximity to the CDE.

5. The apparatus of claim 3, wherein the CDE comprises a conductive area located adjacent to one of the display pixels.

6. The apparatus of claim 1, further comprising:

processing logic coupled to the sensors, the processing logic to identify sensors detecting changes in capacitance greater than a reference capacitance.

7. The apparatus of claim 6, further comprising:

pointing logic coupled to the processing logic, the pointing logic to identify one or more display pixels associated with sensors identified by the processing logic.

8. The apparatus of claim 1, wherein the array of display pixels comprise liquid crystal display (LCD) pixels.

9. A method comprising:

providing a voltage pulse to a plurality of capacitance detection elements (CDEs), each CDE of the plurality of CDEs associated with a different display pixel area;

obtaining, from each CDE of the plurality of CDEs, a voltage profile corresponding to the voltage pulse; and

determining, in response to the voltage profile, a change in capacitance associated with each CDE.

10. The method of claim 9, wherein determining, in response to the voltage profile, a change in capacitance associated with each CDE, comprises:

comparing, for each CDE, a characteristic of the CDE'"'"'s voltage profile to a respective characteristic of a reference voltage profile.

11. The method of claim 10, wherein the characteristic is one of a voltage profile area, a voltage profile height or voltage profile rate of change.

12. The method of claim 9, further comprising:

providing proximity information, the proximity information identifying display pixel areas associated with those CDEs having a change in capacitance greater than a threshold change in capacitance.

13. The method of claim 12, wherein identifying display pixel areas comprises:

simultaneously identifying a plurality display pixel areas associated with those CDEs having a change in capacitance greater than a threshold change in capacitance.

14. A system comprising;

a display panel, the display panel including an array of display pixels and a plurality of capacitance detectors distributed amongst the display pixels;

logic to determine changes in capacitance of the plurality of capacitance detectors; and

logic to identify those display pixels associated with each capacitance detector determined to have a change in capacitance greater than a threshold change in capacitance.

15. The system of claim 14, wherein each capacitance detector of the plurality of capacitance detectors comprises:

a transimpedance amplifier (TIA);

a capacitance detection element (CDE) coupled to the TIA; and

a buffer coupled to the CDE.

16. The system of claim 15, wherein the TIA is to supply a voltage pulse to the CDE, and wherein the buffer is to obtain a voltage profile from the CDE, the voltage profile to correspond to the voltage pulse as modified by capacitive coupling of an object in proximity to the CDE.

17. The system of claim 15, wherein the CDE comprises a conductive area located adjacent to one of the display pixels.

18. The system of claim 14, wherein the display pixels are TFT LCD display pixels.

19. The system of claim 18, wherein the plurality of capacitance detectors comprise a plurality of conductive regions formed within some of the same material layers as the display pixels.