Interface Apparatus And Methods

• US 20120075241A1
• Filed: 09/09/2011
• Published: 03/29/2012
• Est. Priority Date: 09/10/2010
• Status: Active Grant

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Bao, Zhenan, Tee, Benjamin Chee-Keong
• Granted Patent: US 9,112,058 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G01L 1/146 for measuring force distributions, e.g. using force arrays G01L1/148 takes precedence
• CPC Class Codes: G01L 1/148 using semiconductive material, e.g. silicon
• CPC Class Codes: G06F 2203/04102 Flexible digitiser, i.e. constructional details for allowing the whole digitising part of a device to be flexed or rolled like a sheet of paper
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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: H01L 29/84 controllable by variation of applied mechanical force, e.g. of pressure
• CPC Class Codes: H10K 10/464 Lateral top-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 85/623 containing five rings, e.g. pentacene
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

Input devices are provided. In accordance with an example embodiment, an input device includes an interface layer that flexes in response to pressure, a plurality of sense electrodes, a dielectric between the sense electrodes and the interface layer, and interconnecting circuitry. The dielectric compresses or expands in response to movement of the interface layer, and exhibits dielectric characteristics that vary based upon a state of compression of the dielectric. The interconnecting circuitry is to the sense electrodes and provides an output indicative of both the position of each sense electrode and an electric characteristic at each sense electrode that provides an indication of pressure applied to the dielectric adjacent the respective sense electrodes.

Claims

1. An apparatus comprising:

an interface layer configured and arranged to flex in response to an input signal presented to the interface in the form of pressure;

a dielectric structure including an elastomeric material that is configured and arranged to exhibit a first dielectric constant and, in response to the pressure, to compress and thereby exhibit a changed dielectric constant corresponding to a state of compression of the elastomeric material; and

a sense circuit configured and arranged to respond to the change in dielectric constant by providing an indication of the pressure applied to the dielectric.

2. The apparatus of claim 1, wherein the sense circuit includes a plurality of sense electrodes, each sense electrode being configured and arranged to respond to a change in the dielectric constant of a portion of the elastomeric material immediately adjacent the sense electrode, relative to portions of the elastomeric material adjacent other sense electrodes, therein providing an indication of both a pressure applied to the interface layer and a position of the applied pressure on the interface layer.

3. The apparatus of claim 1, wherein the elastomeric material is configured and arranged to compress by compressing negatively and therein expanding in response to a drop in pressure applied to the interface layer.

4. The apparatus of claim 1, wherein the first dielectric constant corresponds to a dielectric constant of the elastomeric material in an uncompressed state.

5. The apparatus of claim 1,

further including at least one electrode configured and arranged to apply a fringing-field capacitance to the sense circuit via the dielectric material,

wherein the sense circuit is configured and arranged to generate an electrical output based on the fringing-field capacitance applied thereto.

6. The apparatus of claim 1, wherein

the sense circuit includes a plurality of electrodes arranged on a planar substrate, and

the dielectric structure is located between the substrate and the interface layer and configured and arranged to compress between the interface layer and at least one of the electrodes in response to pressure applied to a portion of the interface layer over the at least one of the electrodes.

7. The apparatus of claim 1, further including a logic circuit connected to the interconnecting circuits and configured and arranged to process outputs from the sense electrodes to determine pressure applied to at least one of the sense outputs and a location of the applied pressure.

8. A touch screen device comprising:

a substrate having a plurality of sensors, each sensor including electrodes electrically coupled by a compressible elastomeric material that is configured and arranged to compress in response to pressure applied thereto and thereby exhibit a dielectric constant that changes in response to a state of compression thereof, each sensor being configured and arranged to exhibit a change in capacitance between the electrodes in response to the compression of the elastomeric material;

a conductive shielding material on the elastomeric material and configured and arranged to pass light for presenting an image for viewing;

a light source configured and arranged to pass light corresponding to an image for viewing through the conductive shielding material; and

interconnecting circuits respectively coupling the sensors and configured and arranged to provide an output indicative of the capacitance of each sensor, and therein providing an indication of an amount of pressure applied to the shielding material adjacent each sensor.

9. The device of claim 8, wherein the sensors are configured and arranged to respond to a change in the dielectric constant of a portion of the elastomeric material immediately adjacent the sensor, relative to portions of the elastomeric material adjacent other sensors, therein providing an indication of both a pressure applied to the elastomeric material and a position of the applied pressure.

10. A method of manufacturing a sensor device, the method comprising:

forming an interface layer configured and arranged to flex in response to an input signal presented to the interface in the form of pressure;

forming a dielectric structure including an elastomeric material that is configured and arranged to exhibit a first dielectric constant and, in response to the pressure, to compress and thereby exhibit a changed dielectric constant corresponding to a state of compression of the elastomeric material; and

forming a sense circuit configured and arranged to respond to the change in dielectric constant by providing an indication of the pressure applied to the elastomeric material.

11. The method of claim 10, further including forming at least one electrode configured and arranged to apply a fringing-field capacitance to the sense circuit via the elastomeric material.

12. The method of claim 10,

wherein forming a sense circuit includes forming a plurality of electrodes on a planar substrate, and

further including placing the dielectric structure on the electrodes and between the planar substrate and the interface layer, to configure the dielectric structure to compress between the interface layer and at least one of the electrodes in response to pressure applied to a portion of the interface layer over the at least one of the electrodes.