Sensor device and sensing method based on an electroactive material

Patent metadata

Field	Value
Publication number	US-2019050102-A1
Application number	US-201716077100-A
Country	US
Kind code	A1
Filing date	Feb 13, 2017
Priority date	Feb 29, 2016
Publication date	Feb 14, 2019
Grant date	—

Abstract

A sensor device comprising a passive matrix array of electroactive sensor elements arranged in rows and columns. In one example, each sensor element generates a binary sensor signal such that a total signal at each row and at each column enables any pattern of external inputs to be determined. This provides a first way to determine a pattern of sensor elements which are sensing an input using a passive matrix addressing scheme. In another example, each sensor element generates a sensor signal with a different frequency characteristic. This provides another way to enable any pattern of external inputs to be determined.

First claim

1 . A sensor device comprising:
a passive matrix array of electroactive sensor elements arranged in rows and columns; and an array of row lines and an array of column lines, with a sensor element at each intersection, wherein each sensor element generates a sensor signal when an external input is sensed, wherein each sensor element generates a binary sensor signal such that a total sensor array signal at each row and at each column enables any pattern of external inputs to be determined.

2 . A device as claimed in claim 1 , wherein each sensor element comprises a bistable element having two configurations.

3 . A device as claimed in claim 1 , wherein each sensor element generates a sensor current.

4 . A sensor device comprising:
a passive matrix array of electroactive sensor elements, wherein each sensor element generates a sensor signal when an external input is sensed, wherein each sensor element generates a sensor signal with a different frequency characteristic such that individual sensor elements can be identified from a combined sensor signal, thereby to enable any pattern of external inputs to be determined.

5 . A device as claimed in claim 4 , wherein each sensor element comprises a current generating element which generates an output current in response to an external input, and a reactive load circuit which converts the output current into an output signal with a frequency characteristic.

6 . A device as claimed in claim 5 , wherein the reactive load circuit comprises a resonant circuit, wherein the resonant circuit of each sensor element has a different set of component values.

7 . A device as claimed in claim 6 , wherein the resonant circuit comprises a parallel LC circuit.

8 . A device as claimed in claim 5 , wherein the sensor element further comprises a diode between the current generating element and the load circuit.

9 . A device as claimed in claim 4 comprising a summing circuit for summing the sensor signals.

10 . A device as claimed in claim 4 , wherein each sensor element has a different mechanical resonance frequency or a different mechanical relaxation time.

11 . A sensing method for sensing a pattern of external inputs to a sensor device which comprises a passive matrix array of electroactive sensor elements arranged in rows and columns and an array of row lines and an array of column lines with a sensor element at each intersection, wherein the method comprises:
generating a sensor signal at each sensor element when an external input is sensed, wherein the sensor element signal comprises a binary sensor signal; and from a total sensor signal at each row and at each column determining the pattern of external inputs.

12 . A sensing method for sensing a pattern of external inputs to a sensor device which comprises a passive matrix array of electroactive sensor elements, with a sensor element at each intersection, wherein the method comprises:
generating a sensor signal at each sensor element with a different frequency characteristic; and from a combined sensor signal, identifying individual sensor elements, thereby determining the pattern of external inputs.

13 . A method as claimed in claim 12 , wherein each sensor element comprises a current generating element which generates an output current in response to an external input, and wherein the method comprises converting the output current into an output signal with a frequency characteristic using a load circuit.

14 . A method as claimed in claim 12 , comprising summing the sensor signals and identifying the sensor elements in the summed sensor signals using frequency spectrum analysis.

15 . A method as claimed in claim 12 , comprising providing each sensor element with a different mechanical resonance frequency or a different mechanical relaxation time.

Assignees

• Koninklijke Philips Nv

Inventors

• Johnson Mark Thomas
• Hendriks Cornelis Petrus
• Van Den Ende Daan Anton
• Hilgers Achim

Classifications

• G06F3/0416

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• G06F3/04166

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