Capacitive based digitizer sensor

• US 10,234,996 B2
• Filed: 06/23/2015
• Issued: 03/19/2019
• Est. Priority Date: 06/23/2014
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Barel, Eliyahu
• Primary Examiner(s): Merkoulova, Olga V
• Application Number:
  US14/746,883
• Publication Number:
  US 20150370373A1
• Time in Patent Office: 1,365 Days
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

A sensor includes a sensor layer patterned with conductive elements spread across the sensor layer and a resilient layer proximate to the sensor layer. The conductive elements are electrically isolated from one another. The sensor layer is configured for capacitive based sensing and to detect local compressions based on pressure applied to the resilient layer.

Claims

1. A sensor comprising:

a sensor layer patterned with conductive elements spread across the sensor layer, wherein the conductive elements are electrically isolated from one another and wherein the sensor layer is configured for capacitive based sensing; and

a resilient layer formed with spacer dots coated with a hard coat film and positioned proximate to the sensor layer, the sensor layer configured to detect local changes in capacitance based on pressure applied to the resilient layer,

wherein the spacer dots are formed from a material having a hardness of between 20-40 durometers.

2. The sensor of claim 1, wherein the resilient layer is configured to compress differentially in response to differential pressure.

3. The sensor of claim 1, wherein the resilient layer is 50-500 μ

m thick.

4. The sensor of claim 1, wherein the resilient layer is coated with conductive material.

5. The sensor of claim 4, wherein the conductive material is coated on a surface of the resilient layer that faces away from the sensor layer.

6. The sensor of claim 1, wherein the sensor layer is formed from a rigid substrate patterned with conductive elements.

7. The sensor of claim 1, wherein the sensor layer is 0.1-1 mm thick.

8. The sensor of claim 1, wherein the sensor layer is pressure sensitive.

9. The sensor of claim 1, wherein the conductive elements are patterned in a grid.

10. The sensor of claim 1, wherein the sensor is configured to detect an object interacting while water is present on the surface over which the user interacts with the sensor.

11. The sensor of claim 1, wherein the sensor is configured to detect an object that is not conductive.

12. The sensor of claim 1 wherein the hard coat film is an interacting surface of the sensor.

13. The sensor of claim 1, wherein an air gap is established between the sensor layer and a display, or between the sensor layer and a protective cover, and wherein a volume of air in the air gap is removed based on bowing of the sensor.

14. A sensor comprising:

a sensor layer formed with flexible substrate and patterned with conductive elements spread across the sensor layer, wherein the conductive elements are electrically isolated from one another and wherein the sensor layer is configured for capacitive based sensing;

an array of spacer dots coated with a hard coat film proximate to the sensor layer and providing a surface over which the sensor layer is mounted, wherein the spacer dots are configured to compress differentially in response to differential pressure, wherein the spacer dots are formed from a material having a hardness of between 20-40 durometers; and

a circuit configured to detect local changes in capacitance between the conductive elements based on compression of the spacer dots in the array.

15. The sensor of claim 14, wherein the diameter of spacer dots is 20-200 μ

m.

16. The sensor of claim 14, wherein the sensor layer is operative to bend at an interaction location in response to pressure applied by an object interacting with the sensor.

17. The sensor of claim 14, wherein the conductive elements are patterned in a grid.

18. The sensor of claim 14, wherein the sensor is configured to detect an object interacting while water is present on the surface over which the user interacts with the sensor.

19. A sensor comprising:

a sensor layer including a first sub-layer patterned with a first array of conductive elements and a second sub-layer patterned with a second array of conductive elements, both spread across the sensor layer, wherein the conductive elements are electrically isolated from one another and wherein the sensor is configured for capacitive based sensing; and

an array of spacer dots separating the first sub-layer from the second sub-layer, wherein the spacer dots are coated with a hard coat film and are configured to be compressed based on pressure applied by an object interacting with the sensor, wherein the spacer dots are formed from a material having a hardness of between 20-40 durometers.

20. The sensor of claim 19, wherein the first sub-layer is configured to make conductive contact with the second sub-layer at an interaction location based on a pre-defined pressure applied on the sensor by the object interacting with the sensor.

21. The sensor of claim 19, wherein the sensor is configured to detect an object interacting while water is present on the surface over which the user interacts with the sensor.