TOUCHSCREEN FOR DETECTING MULTIPLE TOUCHSCREENS

• US 20120280942A1
• Filed: 07/16/2012
• Published: 11/08/2012
• Est. Priority Date: 04/25/2007
• Status: Active Grant

• Current Assignee: Elo Touch Solutions, Inc.
• Original Assignee: Elo Touch Solutions, Inc.
• Inventors: Kent, Joel C., Aroyan, James L., Gao, Ting, Tanaka, Yoshikazu, Scharff, Daniel H.
• Granted Patent: US 9,454,266 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0436 in which generating transducers and detecting transducers are attached to a single acoustic waves transmission substrate

Abstract

A touchscreen system comprises a touch area. At least one transmitter is positioned proximate to outer edges of the touch area for transmitting first beams in a first direction. At least one beam splitter is positioned proximate to the outer edges of the touch area for splitting the first beams into at least second and third beams that travel through the touch area in at least second and third directions, respectively. The at least one beam splitter comprises a plurality of deflecting elements. Receivers are positioned proximate to the outer edges of the touch area for receiving the at least second and third beams.

Claims

1. A touchscreen system, comprising:

a substrate comprising a touch area having X and Y dimensions;

a first X array and a first Y array being fabricated on the substrate proximate to outer edges of the touch area;

transmit transducers configured to transmit beams through the first X and Y arrays, the first X and Y arrays being configured to deflect the beams towards the touch area;

first and second beam splitters fabricated on the substrate between the first X and Y arrays, respectively, and the touch area, the first and second beam splitters each comprising a plurality of deflecting elements and being configured to split the beams into at least two beams that travel through the touch area in different directions with respect to each other; and

receive transducers configured to receive the at least two beams,

wherein the transmit transducers comprise at least one surface acoustic wave transmit transducer and the receive transducers comprise at least one surface acoustic wave receive transducer.

2. The system of claim 1, wherein each of the first and second beam splitters comprising a top side and a bottom side, the bottom side interfacing with the substrate, and further comprising a seal being formed at least along the top side of the first and second beam splitters.

3. The system of claim 1, further comprising:

a second X array and a second Y array being fabricated on the substrate proximate to the outer edges of the touch area; and

third and fourth beam splitters being fabricated on the substrate between the second X and Y arrays, respectively, and the touch area, the third and fourth beam splitters being configured to deflect the at least two beams toward the receive transducers.

4. The system of claim 1, wherein the beam splitters are configured to cause one of the at least two beams to travel through the touch area along one of an X or Y direction and the cause the other of the at least two beams to travel through the touch area in a U direction at a diagonal angle.

5. The system of claim 4, further comprising a second array proximate to the outer edges, wherein the array is configured to deflect the other of the at least two beams from the U direction.

6. The system of claim 1, wherein each of the deflecting elements comprises a linear segment fabricated on the substrate.

7. The system of claim 1, wherein the beam splitters are configured to split the beams into at least three beams that travel through the touch area in different directions with respect to each other such that:

one of the at least three beams travels through the touch area along one of an X or Y direction,

another of the other of the at least three beams travels through the touch area in a U direction at a diagonal angle, and

yet another of the at least three beams travels through the touch area in a V direction at a diagonal angle.

8. The system of claim 7, wherein the beam splitters comprise a superposition of two or more pluralities of deflecting elements, the two or more pluralities of deflecting elements having different respective orientations.

9. The system of claim 1, wherein the plurality of deflecting elements comprises screen printed glass frit material.

10. The system of claim 1, wherein the plurality of deflecting elements comprises composite polymer material ink.

11. The system of claim 1, wherein the plurality of deflecting elements comprises etched grooves.

12. A method for detecting multiple touches on a touchscreen system, comprising:

transmitting, via at least one surface acoustic wave transmitter, first beams proximate to an outer edge of a touch area;

splitting the first beams to form at least second and third beams traveling in different directions through the touch area with respect to each other;

splitting the at least second and third beams traveling in different directions to form receive beams;

receiving, via at least one surface acoustic wave receiver, the receive beams; and

detecting a location of at least one externally generated touch within the touch area based on the receive beams.

13. The method of claim 12, further comprising deflecting portions of the first beams towards the touch area as the first beams travel along the outer edges of the touch area.

14. The method of claim 12, further comprising deflecting the receive beams to travel along the outer edges of the touch area.

15. The method of claim 12, wherein splitting the first beams to form at least second and third beams traveling in different directions through the touch area with respect to each other comprises splitting the first beams to form a second beam traveling through the touch area in one of an X or Y direction and a third beam traveling through the touch area in a U direction at a different diagonal angle.

16. The method of claim 15, wherein splitting the first beams to form at least second and third beams traveling in different directions through the touch area with respect to each other further comprises splitting the first beams to faun a fourth beam traveling in a V direction at a diagonal angle.

17. An electronic device comprising a touchscreen, the touchscreen comprising:

a substrate comprising a touch area having at least two horizontal outer edges and at least two vertical outer edges;

a first horizontal array proximate to one of the horizontal outer edges and a first vertical array proximate to one of the vertical outer edges;

transmit transducers configured to transmit beams through the first horizontal and vertical arrays, the first horizontal and vertical arrays being configured to deflect the beams towards the touch area;

first and second beam splitters fabricated on the substrate between the first horizontal and vertical arrays, respectively, and the touch area, the first and second beam splitters each comprising a plurality of deflecting elements and being configured to split the beams into at least two beams that travel through the touch area in different directions with respect to each other; and

receive transducers configured to receive the at least two beams,

wherein the transmit transducers comprise at least one surface acoustic wave transmit transducer and the receive transducers comprise at least one surface acoustic wave receive transducer.

18. The electronic device of claim 17, wherein the touchscreen further comprises:

a second horizontal array proximate to the other of the at least two horizontal outer edges and a second vertical array proximate to the other of the at least two vertical outer edges; and

third and fourth beam splitters being fabricated on the substrate between the second horizontal and vertical arrays, respectively, and the touch area, the third and fourth beam splitters being configured to deflect the at least two beams toward the receive transducers.

19. The electronic device of claim 17, wherein the beam splitters are configured to cause one of the at least two beams to travel through the touch area along one of a horizontal or vertical direction and cause the other of the at least two beams to travel through the touch area in a diagonal direction.

20. The electronic device of claim 17, wherein the beam splitters are configured to split the beams into at least three beams that travel through the touch area in different directions with respect to each other such that:

one of the at least three beams travels through the touch area along one of a horizontal or vertical direction,

another of the other of the at least three beams travels through the touch area in a first diagonal direction, and

yet another of the at least three beams travels through the touch area in a second diagonal direction that is different from the first diagonal direction.