Method and a touch sensing device for implementing the method
AssigneeElo Touch Solutions, Inc.
InventorJoel C. Kent
Life of this patent
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Abstract
The present invention relates to a method for reducing noise in a signal sensing a bending wave propagating in an object comprising the steps of: receiving a sensed signal representative of a plurality of locations of the object, and fitting a function satisfying bending wave propagation properties to the sensed signals, thereby reducing noise contributions to the sensed signals not satisfying the bending wave propagation properties. By doing so, noise contributions not satisfying the wave propagation properties can be suppressed from the sensed signal, thereby improving the signal-to-noise ratio.
Claims17
A method for reducing noise in a signal sensing a bending wave propagating in an object comprising the steps of:
- a) causing, via a control unit of a touch sensing device, at least one bending wave to propagate through a touch sensing device;
- b) receiving one or more sensed signals, via the control unit of the touch sensing device, representative of a plurality of locations of the object;
- and
- c) fitting a function satisfying bending wave propagation properties to the one or more sensed signals, thereby reducing noise contributions to the one or more sensed signals not satisfying the bending wave propagation properties, wherein the bending wave propagation properties comprise properties configured to satisfy the Helmholtz equation, and wherein a bending wave dispersion relation
- k
- =
- ω
-
- [
- 12
-
- (
- 1
- -
- υ
- 2
- )
-
- ρ
- Eh
- 2
- ]
- 1
- /
- 4
- ,
- with ω being the angular frequency of the bending wave propagating in the object, E, υ and ρ being respectively the modulus of elasticity, the Poisson's ratio and the density of the object and h being the thickness of the object, is satisfied by the fitting function.
A method for reducing noise in one or more signals sensing at least one bending wave propagating in a touch sensing device comprising:
- causing, via a control unit of the touch sensing device, the at least one bending wave to propagate through the touch sensing device;
- determining a plurality of locations of the one or more signals sensing the at least one bending wave;
- and
- fitting a function satisfying bending wave propagation properties to the one or more signals, received via the control unit of the touch sensing device, thereby reducing noise contributions to the one or more signals not satisfying the bending wave propagation properties, wherein the bending wave propagation properties comprise properties configured to satisfy the Helmholtz equation, and wherein a bending wave dispersion relation
- k
- =
- ω
-
- [
- 12
-
- (
- 1
- -
- υ
- 2
- )
-
- ρ
- Eh
- 2
- ]
- 1
- /
- 4
- ,
- with ω being the angular frequency of the bending wave propagating in the object, E, υ and ρ being respectively the modulus of elasticity, the Poisson's ratio and the density of the object and h being the thickness of the object, is satisfied by the fitting function.
Dependencies are inferred from the claim text.