Acoustic touch apparatus
View Patent ↗Acoustic touch apparatus comprising a substrate having first and second surfaces capable of propagating surface acoustic waves, the second surface comprising a touch region and the first and second surfaces coupled via a rounded connecting surface; at least one acoustic wave transducer on the first surface; and at least one reflective array on the first surface. The transducer is capable of transmitting or receiving waves to and from the reflective array. The substrate and reflective array can acoustically couple waves between the first and second surfaces. The substrate has a border region on the first surface adapted to hide the transducer and reflective array and preclude distortion of waves propagating over a window in the border region. The border region may have a border layer except at the window and a corrective lens is used proximate the window, or the border region comprises discolored glass except at the window.
1. An acoustic touch apparatus, comprising;
a substrate having a first surface and a second surface, the first and second surfaces capable of propagating surface acoustic waves, the second surface comprising a touch region and the first and second surfaces coupled via a rounded connecting surface;
at least one acoustic wave transducer on the first surface; and
at least one reflective array on the first surface, said transducer capable of transmitting or receiving surface acoustic waves to and from said reflective array, said substrate and said reflective array capable of acoustically coupling surface acoustic waves to propagate between the first and second surfaces, and said substrate having a border region on the first surface that is adapted to hide from view through the substrate the transducer and the reflective array and to preclude distortion of surface acoustic waves propagating over a window in the border region via an acoustic lens that counteracts a phase shift of surface acoustic waves propagating over the window, wherein the border region comprises a border layer on the first surface.
2. The apparatus of claim 1 , wherein the border region comprises the border layer on the first surface and includes the acoustic lens that counteracts the phase shift of surface acoustic waves propagating over the window, the window being an uncoated area in the border layer.
3. The apparatus of claim 2 , wherein the window is an uncoated border area in the border layer on the first surface.
4. The apparatus of claim 3 , wherein the acoustic lens has a height that counteracts the phase shift of surface acoustic waves along all propagation paths through the window.
5. The apparatus of claim 3 , wherein the acoustic lens is disposed on the border layer to be physically close to the window and have a symmetrical outline relative to the window.
6. The apparatus of claim 3 , wherein a height of the acoustic lens is specified by the following:
y ′( x )= Y corr· y ( x )
where y′(x) is the height along an X-coordinate of the acoustic lens perpendicular to direction of propagation of the surface acoustic waves; y(x) is the known height along the X-coordinate; and Ycorr is a constant, dependent, only on the surface acoustic wave velocities of propagation, defined as follows:
Y corr=( V 2 /V 0 )·[( V 0 −V 1 )/( V 1 −V 2 )]
where V 0 is the surface acoustic wave phase velocity in the window; V 1 is the surface acoustic wave phase velocity on the border layer except on the window; and V 2 is the surface acoustic wave phase velocity of the acoustic lens on the border layer.
7. The apparatus of claim 3 , wherein the acoustic lens is a two-sided meniscus shaped lens that at least partially circumscribes the window.
8. The apparatus of claim 3 , wherein the acoustic lens is a one-sided meniscus shaped lens that at least partially circumscribes the window.
9. The apparatus of claim 2 , wherein the acoustic lens comprises an unobstructed optical path that extends through a border layer on the border region of the substrate from the first surface to the second surface, said acoustic lens and said window disposed adjacent one another on the first surface.
10. The apparatus of claim 9 , the acoustic lens is comprised of a material that reduces surface acoustic wave velocity of propagation relative to surface acoustic waves propagating through the window.
11. The apparatus of claim 9 , wherein the acoustic lens has a height that counteracts the phase shift of surface acoustic waves along all propagation paths through the window.
12. The apparatus of claim 1 , wherein the substrate and the window comprise transparent glass material and the border region excluding the window comprises colored glass material.
13. The apparatus of claim 12 , wherein the colored glass material has been colored by a glass staining.
14. The apparatus of claim 12 , wherein the colored glass material has been colored by an ion-exchange coloring.
15. The apparatus of claim 12 , wherein the colored glass material has been colored by using electron beaming.
16. The apparatus of claim 12 , wherein the colored glass material has been colored at least partially through a thickness of the substrate.
17. The apparatus of claim 12 , wherein the border region has the same acoustic properties as the touch region on the second surface, the acoustic properties comprising propagating surface acoustic waves, and different optical properties from the touch region, the optical properties of the border region comprising the colored glass material.
18. An acoustic touch apparatus, comprising:
a substrate having a first surface and a second surface, the first and second surfaces capable of propagating surface acoustic waves, the second surface comprising a touch region and the first and second surfaces coupled via a rounded connecting surface;
at least one acoustic wave transducer on the first surface; and
at least one reflective array on the first surface, said transducer capable of transmitting or receiving surface acoustic waves to and from said reflective array, said substrate and said reflective array capable of acoustically coupling surface acoustic waves to propagate between the first and second surfaces, and said substrate having a border region on the first surface, wherein the border region comprises a border layer on the first surface and includes an acoustic lens that counteracts a phase shift of surface acoustic waves propagating over a window, the first surface adapted to hide from view through the substrate the transducer and the reflective array and to preclude distortion of surface acoustic waves propagating over the window in the border region, the window being an uncoated area in the border layer.
19. An acoustic touch apparatus, comprising:
a substrate having a first surface and a second surface, the first and second surfaces capable of propagating surface acoustic waves, the second surface comprising a touch region and the first and second surfaces coupled via a rounded connecting surface;
at least one acoustic wave transducer on the first surface; and
at least one reflective array on the first surface, said transducer capable of transmitting or receiving surface acoustic waves to and from said reflective array, said substrate and said reflective array capable of acoustically coupling surface acoustic waves to propagate between the first and second surfaces, and said substrate having a border region on the first surface that is adapted to hide from view through the substrate the transducer and the reflective array and to preclude distortion of surface acoustic waves propagating over a window in the border region via an acoustic lens that counteracts a phase shift of surface acoustic waves propagating over the window, wherein the border region comprises a border layer on the first surface and wherein the substrate and the window comprise transparent glass material and the border region excluding the window comprises colored glass material.
20. The apparatus of claim 19 , wherein the border region has the same acoustic properties as the touch region on the second surface the acoustic properties comprising propagating surface acoustic waves, and different optical properties from the touch region, the optical properties of the border region comprising colored glass material.