Abstract: An acoustic touch position sensor is shown in which a transducer coupled to a side of a substrate imparts a shear wave into the substrate for propagation along a first axis. A reflective array is disposed along the first axis to reflect portions of the shear wave along a plurality of parallel paths extending across a touch surface of the substrate to a second reflective array the axis of which is parallel to the axis of the first reflective array. The second reflective array reflects the shear waves incident thereto to a transducer mounted on the side of the substrate and responsive to shear waves propagated thereto for providing a signal representative of these shear waves. A touch on the substrate results in a partial absorption of the energy in the shear wave so as to produce a perturbation therein which is sensed to determine the axial position of the touch on the substrate.

Abstract: An acoustic touch position sensor is shown in which a transducer coupled to a side of a substrate imparts a shear wave into the substrate for propagation along a first axis. A reflective array is disposed along the first axis to reflect portions of the shear wave along a plurality of parallel paths extending across a touch surface of the substrate to a second reflective array the axis of which is parallel to the axis of the first reflective array. The second reflective array reflects the shear waves incident thereto to a transducer mounted on the side of the substrate and responsive to shear waves propagated thereto for providing a signal representative of these shear waves. A touch on the substrate results in a partial absorption of the energy in the shear wave so as to produce a perturbation therein which is sensed to determine the axial position of the touch on the substrate.

Abstract: An acoustic touch position sensor is shown in which a transducer coupled to a side of a substrate imparts a shear wave into the substrate for propagation along a first axis. A reflective array is disposed along the first axis to reflect portions of the shear wave along a plurality of parallel paths extending across a touch surface of the substrate to a second reflective array the axis of which is parallel to the axis of the first reflective array. The second reflective array reflects the shear waves incident thereto to a transducer mounted on the side of the substrate and responsive to shear waves propagated thereto for providing a signal representative of these shear waves. A touch on the substrate results in a partial absorption of the energy in the shear wave so as to produce a perturbation therein which is sensed to determine the axial position of the touch on the substrate.

Abstract: An acoustic touch position sensor is shown wherein a Lamb wave is imparted into a substrate by a transducer mounted on the substrate, the Lamb wave propagating along a first axis. Top and bottom reflecting arrays are disposed along the first axis to reflect portions of one mode of the Lamb wave along a plurality of parallel paths extending across a touch surface of the substrate to a second pair of top and bottom reflect arrays. The second pair of top and bottom reflecting arrays reflect the Lamb waves incident thereto along an axis parallel to the first axis to a receiving transducer that provides a signal representative of the received Lamb waves. A touch on the substrate results in a partial absorption of the energy in the Lamb wave propagating along a path intersection the touch position so as to produce a perturbation therein which is sensed to determine the axial position of the touch on the substrate.

Abstract: An acoustic touch position sensor is shown wherein a transducer coupled to a side of a substrate imparts a shear wave into the substrate that propagates along a first axis. A shear to Lamb wave converting array disposed along the first axis converts the shear wave to Lamb waves propagating along a plurality of parallel paths where each path is associated with a different axial position on the substrate relative to the first axis. The Lamb waves are converted back to shear waves by a Lamb to shear wave converting array disposed along an axis parallel to the first axis, the second converting array being spaced across a touch surface of the substrate from the first array. The shear wave from the second converting propagate to a receiving transducer that provides a signal representative of the waves.