Input Device

• US 20080018611A1
• Filed: 02/27/2007
• Published: 01/24/2008
• Est. Priority Date: 07/18/2006
• Status: Abandoned Application

• Current Assignee: IEE International Electronics & Engineering SA (Aerospace Hi-Tech Holding Group Company Limited)
• Original Assignee: IEE International Electronics & Engineering SA (Aerospace Hi-Tech Holding Group Company Limited)
• Inventors: Schoos, Aloyse, Boyer, Philippe, Serban, Bogdan
• Application Number:
  US11/679,535
• Publication Number:
  US 20080018611A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04106 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 3/04144 using an array of force sensing means position sensing using the local deformation of sensor cells G06F3/0447
• 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 3/0445 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 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: H03K 17/975 using a capacitive movable element

Abstract

An input device comprises a capacitive proximity and pressure sensor, which includes a first carrier layer, a second carrier layer and a spacer arranged between the first and second carrier layers, the first carrier layer having a first capacitor electrode applied thereon, the second carrier layer having a second capacitor electrode applied thereon, the first and second capacitor electrodes being arranged opposite one another with respect to the spacer in such a way that, in response to a compressive force acting on the pressure sensor, the first and second capacitor electrodes are brought closer together. The input device further comprises a control circuit configured so as to operate in at least two modes of operation, including a first and a second mode of operation. The control circuit determines, while in the first mode of operation, a quantity indicative of a capacitance between the first capacitor electrode and ground and, while in the second mode of operation, a quantity indicative of a capacitance between the first capacitor electrode and the second capacitor electrode.

Claims

1. An input device comprising

a capacitive proximity and pressure sensor, including a first carrier layer, a second carrier layer and a spacer arranged between said first and second carrier layers, said first carrier layer having a first capacitor electrode applied thereon, said second carrier layer having a second capacitor electrode applied thereon, said first and second capacitor electrodes being arranged opposite one another with respect to said spacer in such a way that, in response to a compressive force acting on the pressure sensor, the first and second capacitor electrodes are brought closer together;

and a control circuit configured so as to operate in at least a first and a second mode of operation, said control circuit determining,

while in said first mode of operation, a quantity indicative of a capacitance between said first capacitor electrode and ground;

and, while in said second mode of operation, a quantity indicative of a capacitance between said first capacitor electrode and said second capacitor electrode.

2. The input device as claimed in claim 1, wherein said spacer has an opening therein, said first and second capacitor electrodes being arranged opposite one another with respect to said opening of the spacer, wherein said first and/or said second capacitor electrode has an insulating layer or insulating pattern arranged thereon in such a way as to prevent a short circuit between said first and second capacitor electrodes when said first and second capacitor electrodes are brought closer together.

3. The input device as claimed in claim 1, wherein said spacer is electrically insulating and compressible, and wherein said first and second capacitor electrodes are brought closer together when said spacer is compressed in response to a compressive force acting on the pressure sensor.

4. The input device as claimed in claim 1, wherein said control circuit determines, while in said first mode of operation, an amount of electric charge accumulated on said first capacitor electrode in response to applying a defined voltage to said first capacitor electrode.

5. The input device as claimed in claim 1, wherein said control circuit determines, while in said first mode of operation, an amplitude and/or a phase of a loading current flowing in said first capacitor electrode in response to applying an oscillating voltage to said first capacitor electrode.

6. The input device as claimed in claim 1, wherein said control circuit determines, while in said first mode of operation, an in-phase component and/or a 90°

-phase-offset component of a loading current flowing in said first capacitor electrode in response to applying an oscillating voltage to said first capacitor electrode.

7. The input device as claimed in claim 1, wherein said control circuit determines, while in said first mode of operation, a charge time and/or a discharge time of said first capacitor electrode.

8. The input device as claimed in claim 1, wherein said control circuit, while in said first mode of operation, applies a first voltage to said first electrode and a second voltage to said second electrode, said first and second voltages having same amplitude and phase.

9. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, an amount of electric charge accumulated on one of said first and second capacitor electrodes in response to an applying a defined voltage to the other of said first and second capacitor electrodes.

10. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, an amount of electric charge accumulated on one of said first and second capacitor electrodes in response to an applying a defined voltage to said one of said first and second capacitor electrodes.

11. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, an amplitude and/or a phase of a coupling current flowing in one of said first and second capacitor electrodes in response to applying an oscillating voltage to the other of said first and second capacitor electrodes.

12. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, an amplitude and/or a phase of a loading current flowing in one of said first and second capacitor electrodes in response to applying an oscillating voltage to said one of said first and second capacitor electrodes.

13. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, an in-phase component and/or a 90°

-phase-offset component of a coupling current flowing in one of said first and second capacitor electrodes in response to applying an oscillating voltage to the other of said first and second capacitor electrodes.

14. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, an in-phase component and/or a 90°

-phase-offset component of a loading current flowing in one of said first and second capacitor electrodes in response to applying an oscillating voltage to said one of said first and second capacitor electrodes.

15. The input device as claimed in claim 1, wherein said control circuit determines, while in said second mode of operation, a charge and/or a discharge time of said first and/or said second capacitor electrode.

16. The input device as claimed in claim 1, wherein said first carrier layer, said spacer and said second carrier layer are laminated together.

17. The input device as claimed in claim 1, wherein said first carrier layer has a plurality of first capacitor electrodes applied thereon, said second carrier layer having a plurality of second capacitor electrodes applied thereon, each one of said plurality of first capacitor electrodes being arranged opposite a respective one of said plurality of second capacitor electrodes with respect to said spacer in such a way that, in response to a compressive force acting on the pressure sensor, respectively opposite ones of said first and second capacitor electrodes are brought closer together;

and wherein said control circuit determines

while in said first mode of operation, a quantity indicative of a capacitance between individual ones of said plurality of first capacitor electrodes and ground;

and, while in said second mode of operation, a quantity indicative of a capacitance between individual ones of said plurality of first capacitor electrodes and the respectively opposite ones of said plurality of second capacitor electrodes.

18. The input device as claimed in claim 1, wherein said first carrier layer has a plurality of first elongated capacitor electrodes applied thereon, wherein said second carrier layer has a plurality of second elongated capacitor electrodes applied thereon, said plurality of first capacitor electrodes being arranged opposite said plurality of second capacitor electrodes with respect to said spacer, said first elongated capacitor electrodes extending transversally to said second elongated capacitor electrodes in such a way that, in response to a compressive force acting locally on the pressure sensor, opposite ones of said first and second capacitor electrodes are brought closer together at the location where said compressive force acts on the pressure sensor;

and wherein said control circuit determines,

while in said first mode of operation, a quantity indicative of capacitance between individual ones of said plurality of first capacitor electrodes and ground;

and, while in said second mode of operation, a quantity indicative of a capacitance between individual ones of said plurality of first capacitor electrodes and individual ones of said plurality of second capacitor electrodes.

19. The input device as claimed in claim 1, wherein said spacer has a plurality of openings therein, wherein said first carrier layer has a plurality of first capacitor electrodes applied thereon, wherein said second carrier layer has a plurality of second capacitor electrodes applied thereon, each one of said plurality of first capacitor electrodes being arranged opposite a respective one of said plurality of second capacitor electrodes with respect to a respective one of said plurality of openings in such a way that, in response to a compressive force acting on the pressure sensor, respectively opposite ones of said first and second capacitor electrodes are brought closer together;

and wherein said control circuit determines,

while in said first mode of operation, a quantity indicative of capacitance between individual ones of said plurality of first capacitor electrodes and ground;

and, while in said second mode of operation, a quantity indicative of a capacitance between individual ones of said plurality of first capacitor electrodes and the respectively opposite ones of said plurality of second capacitor electrodes.

20. An input device comprising

a capacitive proximity and pressure sensor, including a first carrier layer, a second carrier layer and a spacer arranged between said first and second carrier layers for keeping the first and second carrier layers apart from one another, said first carrier layer having a plurality of first capacitor electrodes applied thereon, said second carrier layer having a second capacitor electrode applied thereon, said plurality of first capacitor electrodes being arranged opposite said second capacitor electrode with respect to said spacer in such a way that, in response to a compressive force acting locally on the pressure sensor, individual ones of said first capacitor electrodes are brought closer to said second capacitor electrode at the location where said compressive force acts on the pressure sensor;

and a control circuit configured so as to operate in at least a first and a second mode of operation, said control circuit determining,

while in said first mode of operation, a quantity indicative of capacitance between individual ones of said first capacitor electrodes and ground;

and, while in said second mode of operation, a quantity indicative of a capacitance between said second capacitor electrode and individual ones of said first capacitor electrodes.

21. The input device as claimed in claim 20, wherein, wherein said spacer has an opening therein, said plurality of first capacitor electrodes being arranged opposite said second capacitor electrode with respect to said opening of the spacer, wherein capacitive electrodes of said plurality of first capacitive electrodes and/or said second capacitor electrode have an insulating layer or insulating pattern arranged thereon in such a way as to prevent a short circuit between capacitive electrodes of said plurality of first capacitive electrodes and said second capacitor electrode.

22. The input device as claimed in claim 20, wherein said spacer is electrically insulating and compressible, and wherein individual ones of said first capacitor electrodes are brought closer to said second capacitor electrode when said spacer is compressed in response to a compressive force acting on the pressure sensor.

23. The input device as claimed in claim 20, wherein said first carrier layer, said spacer and said second carrier layer are laminated together.