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US 10,281,567 B2Granted
Method and apparatus for producing an acoustic field
AssigneeUltrahaptics IP Ltd
InventorsThomas Andrew Carter, Benjamin John Oliver Long, Sriram Subramanian
Life of this patent
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Abstract
The present invention concerns a method and apparatus for the modulation of an acoustic field for providing tactile sensations. A method of creating haptic feedback using ultrasound is provided. The method comprises the steps of generating a plurality of ultrasound waves with a common focal point using a phased array of ultrasound transducers, the common focal point being a haptic feedback point, and modulating the generation of the ultrasound waves using a waveform selected to produce little or no audible sound at the haptic feedback point.
Claims30
A method comprising:
- defining a three-dimensional virtual shape in a volume occupied by an acoustic field by:
- i) producing the acoustic field from a transducer array having known relative positions and orientations;
- ii) defining a plurality of control points wherein each of the plurality of control points have a known spatial relationship relative to the transducer array;
- iii) assigning an amplitude to each of the plurality of control points;
- iv) computing a matrix containing elements which represent, for each of the plurality of control points, the effect that producing a modeled acoustic field having the assigned amplitude with a particular phase at that control point has on the consequential amplitude and phase of the modeled acoustic field at the other control points;
- v) calculating a plurality of eigenvectors of the matrix, each of the plurality of eigenvectors representing a set of relative phases and relative amplitudes of the modeled acoustic field at each of the plurality of control points;
- and
- vi) selecting one of the set of phases and relative amplitudes of the modeled acoustic field and operating the transducer array to cause at least one transducer to output an acoustic wave having an initial amplitude and phase such that the phases and amplitudes of the resultant acoustic field at the control points correspond to the phases and relative amplitudes of the selected set of phases and relative amplitudes of the modeled acoustic field.
5 more elements
A method comprising:
- selecting a plurality of control points to define at least one part of a three-dimensional virtual shape in a volume occupied by an acoustic field by:
- i) producing the acoustic field from a transducer array having known relative positions and orientations;
- ii) defining the plurality of control points wherein each of the plurality of control points have a known spatial relationship relative to the transducer array;
- iii) assigning an amplitude to each of the plurality of control points;
- iv) computing a matrix containing elements which represent, for each of the plurality of control points, the effect that producing a modeled acoustic field having the assigned amplitude with a particular phase at that control point has on the consequential amplitude and phase of the modeled acoustic field at the other control points;
- v) calculating a plurality of eigenvectors of the matrix, each of the plurality of eigenvectors representing a set of relative phases and relative amplitudes of the modeled acoustic field at each of the plurality of control points;
- and
- vi) selecting one of the set of phases and relative amplitudes of the modeled acoustic field and operating the transducer array to cause at least one transducer to output an acoustic wave having an initial amplitude and phase such that the phases and amplitudes of the resultant acoustic field at the control points correspond to the phases and relative amplitudes of the selected set of phases and relative amplitudes of the modeled acoustic field.
5 more elements
Dependencies are inferred from the claim text.