WO2011049730A2

WO2011049730A2 - Acoustic wave switch overlay assembly

Info

Publication number: WO2011049730A2
Application number: PCT/US2010/051103
Authority: WO
Inventors: Mark J. Banfield
Original assignee: Illinois Tool Works Inc.
Priority date: 2009-10-21
Filing date: 2010-10-01
Publication date: 2011-04-28
Also published as: WO2011049730A3

Abstract

An overlay assembly configured to be used with an acoustic wave panel of a device. The assembly includes an overlay face layer including a touch area defining a card window, a pocket layer including a channel aligned with the touch area, a film layer aligned with the overlay face layer and the pocket layer, a switch card secured by at least one of the pocket layer and the film layer, wherein the switch card shows through the card window, a lamp layer including a dampening pad aligned with the switch card and the touch area, and a spacer layer having an opening formed therethrough, wherein the dampening pad is aligned with the opening.

Description

ACOUSTIC WAVE SWITCH OVERLAY ASSEMBLY

RELATED APPLICATIONS

[0001] This application relates to and claims priority benefits from U.S. Provisional Patent Application No. 61/253,748, entitled "System and Method for Illuminating Acoustic Wave Switches," filed October 21, 2009, which is hereby incorporated by reference in its entirety.

FIELD OF EMBODIMENTS OF THE INVENTION

[0002] Embodiments of the present invention generally relate to acoustic wave switches, and, more particularly, to an acoustic wave switch overlay assembly.

BACKGROUND

[0003] Overlays have been used with various types of membrane switches in the past in order to denote configurable specialized functionality. In contrast to membrane switches, acoustic wave switches, such as described, for example, in United States Patent No. 7,106,310, are configured to detect a user's touch through trapped acoustic waves. In general, acoustic wave switches utilize the front surface of a switch or keypad as an engagement surface that is used to detect the touch of an operator.

[0004] However, typical overlays generally do not exhibit sufficient energy absorption properties to be used in conjunction with acoustic wave switches. That is, a touch is detected with respect to an acoustic wave switch through detection of impedance or decay differences when a finger contacts a touch surface. However, typical overlays provide a barrier that attenuates such detection.

SUMMARY OF EMBODIMENTS OF THE INVENTION

[0005] Certain embodiments of the present invention provide an overlay assembly configured to be used with an acoustic wave panel of a device. The overlay assembly may include an overlay face layer including a touch area defining a card window, a pocket layer including a channel aligned with the touch film layer aligned with the overlay face layer and the pocket layer, a switch card secured by at least one of the pocket layer and the film layer, wherein the switch card shows through the card window, a lamp layer including a dampening pad aligned with the switch card and the touch area, and a spacer layer having an opening formed therethrough, wherein the dampening pad is aligned with the opening.

[0006] The switch card may be an interchangeable element having at least one marking thereon that denotes a function of a particular acoustic wave switch on the acoustic wave panel. The marking may be made with an elastomeric ink. As such, the ink does not attenuate detection of impedance or decay differences.

[0007] The touch area of the overlay face layer may be embossed in order to provide a tactile surface for an operator to engage. The overlay face layer may include at least one light window proximate the card window. For example, the card window may be in the center of the touch area, while the light window may be at a corner of the touch area.

[0008] The film layer may include at least one slot configured to receive and retain a tab of the switch card.

[0009] The lamp layer may be configured to radiate light through electroluminescence.

[0010] The dampening pad may be formed of elastomeric ink.

[0011] The layers may be sandwiched and laminated together. For example, the layers may be laminated together with an acrylic adhesive. Further, the layers may be formed of polyester or polycarbonate, for example.

[0012] The overlay face layer, the pocket layer, and the film layer may be laminated together to form a first sub-assembly, in order to provide ease of customization of the switch cards secured by the pocket and film layers. The lamp layer and the spacer layer may be laminated together to form a second sub-assembly. The first sub-assembly may then be adhesively secured to the second sub-assembly. [0013] The lamp layer and/or the device may include at least one light- emitting diode (LED).

[0014] Certain embodiments of the present invention provide a system including the overlay assembly described above and a device having an acoustic wave panel. The acoustic wave panel includes an acoustic wave switch having an acoustic wave cavity with a touch surface, and a transducer secured to the acoustic wave cavity opposite the touch surface. The transducer is configured to generate a trapped acoustic wave within the acoustic wave cavity.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

[0015] Figure 1 illustrates a front isometric view of a device having acoustic wave switches, according to an embodiment of the present invention.

[0016] Figure 2 illustrates an isometric, partial cross-sectional view of an acoustic wave switch, according to an embodiment of the present invention.

[0017] Figure 3 illustrates an isometric, exploded front view of an overlay assembly, according to an embodiment of the present invention.

[0018] Figure 4 illustrates an isometric, exploded rear view of an overlay assembly, according to an embodiment of the present invention.

[0019] Figure 5 illustrates an isometric front view of an overlay assembly, according to an embodiment of the present invention.

[0020] Figure 6 illustrates an isometric rear view of an overlay assembly, according to an embodiment of the present invention.

[0021] Figure 7 illustrates a front view of an overlay face layer, according to an embodiment of the present invention.

[0022] Figure 8 illustrates a front view of a pocket layer, according to an embodiment of the present invention. [0023] Figure 9 illustrates a front view of a film layer, according to an embodiment of the present invention.

[0024] Figure 10 illustrates a rear view of a lamp layer, according to an embodiment of the present invention.

[0025] Figure 11 illustrates a front view of a spacer layer, according to an embodiment of the present invention.

[0026] Figure 12 illustrates an isometric, exploded front view of a device having an overlay assembly, according to an embodiment of the present invention.

[0027] Figure 13 illustrates an isometric, exploded rear view of a device having an overlay assembly, according to an embodiment of the present invention.

[0028] Figure 14 illustrates an isometric front view of a device having an overlay assembly, according to an embodiment of the present invention.

[0029] Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of "including" and "comprising" and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0030] Figure 1 illustrates a front isometric view of a device 10 having acoustic wave switches 12, according to an embodiment of the present invention. The device 10 may be any device that uses acoustic wave switches 12. Further, more or less acoustic wave switches 12 than those shown may be used. [0031] The device 10 includes a cabinet 14 having a base 16, lateral walls 18, a top wall 20, and a rear wall (not shown). The cabinet 14 supports an acoustic wave panel 22 that includes the acoustic wave switches 12.

[0032] The cabinet 14 includes a retaining ridge 24 formed around the front face of the acoustic wave panel 22. The retaining ridge 24 is configured to receive and retain an overlay assembly (described below).

[0033] Figure 2 illustrates an isometric, partial cross-sectional view of an acoustic wave switch (or button) 12, according to an embodiment of the present invention. The acoustic wave switch 12 includes an associated acoustic wave cavity, or resonator, 26 that extends through the thickness b_s of a substrate 28, which may be formed through the acoustic wave panel 22. The substrate 28 may be formed of metal, plastic, glass, ceramic, or the like that is capable of supporting a resonant acoustic wave.

[0034] The acoustic wave cavity 26 is formed in the substrate 28 such that the mass per unit surface area of the acoustic wave cavity 26 is greater than the mass per unit surface area of the substrate 28 adjacent the acoustic wave cavity 26. In one embodiment, the mass per unit area of the substrate 28 in the switch region is increased to form the acoustic wave cavity 26 by forming a thin plateau or mesa 30 on a surface of the substrate 28 that is parallel to the plane of the substrate 28 and/or a touch surface 32, which is configured to be engaged by an operator. The mesa 30 may be formed on a back surface 34 of the substrate 28 opposite the touch surface 32 of the acoustic wave cavity 26. In general, the back surface 34 is secured within an internal chamber defined by the cabinet 14 (shown in Figure 1) and the touch surface 32 is exposed on the front face of the acoustic wave panel 22. Alternatively, the mesa 30 may be formed on the touch surface 32.

[0035] A transducer 36 may be mounted on a surface 38 of the acoustic wave cavity 26 to generate an acoustic wave that is substantially trapped or localized within the acoustic wave cavity 26. Although the transducer 36 is shown as being mounted on the mesa 30, if the mesa 30 is formed on the touch surface 32 of the substrate 28, the transducer 36 may be mounted directly on the substrate surface of the acoustic wave cavity 26 opposite the mesa 30. The transducer 36 is electrically connected to a sensing circuit 40 or separate processing unit secured within the cabinet 14.

[0036] The acoustic wave switch 12 may use any type of acoustic wave capable of being substantially trapped in the acoustic wave cavity 26. For simplicity, the acoustic wave switch 12 is described using a shear wave in a direction that is in the plane of the substrate 28, wherein the shear wave energy extends in a direction perpendicular to the plane of the substrate 28, that is, through the thickness of the substrate 28. A shear wave is advantageous because it is insensitive to liquids and other contaminants on the touch surface 32 of the acoustic wave switch 12.

[0037] Because the fundamental or zeroth order mode of a horizontally polarized shear wave may not be substantially trapped, higher order shear wave modes are used in accordance with embodiments of the present invention. It should be appreciated that because the acoustic wave used is trapped, the wave is a standing wave. A standing wave has a number of advantages over an acoustic wave that propagates or travels along a path in a substrate. For example, propagating waves are not confined to the main path of propagation but can diffract off of the main path complicating touch detection. This is opposed to a standing wave which by its nature is confined to the area of a particular acoustic wave cavity 26. Because the acoustic wave is confined, touch detection is easily accomplished. Further, the wave energy of a propagating wave is not stored at any location along the path. Once a propagating wave passes a point along the path, the wave is gone, thereby making timing and control critical for touch detection with propagating waves. There are no timing or control issues with a standing wave because the wave energy is stored in the acoustic wave cavity 26. Moreover, a propagating wave is not a resonating wave. As such, the wave energy decays as it travels. A standing wave is resonant so that the wave is reinforced and prolonged. As a result, the standing wave has a much greater amplitude than a wave that is not confined. The construction and operation of the acoustic wave cavity 26 is further described in United States Patent No. 7,106,310, entitled "Acoustic Wave Touch Actuated Switch" (The "'310 patent"), which is hereby incorporated by reference in its entirety.

[0038] Embodiments of the present invention provide a system and method of detecting pressure and movement with respect to the touch surface 32 of the acoustic wave switch 12, using acoustic wave energy that employs trapped energy concepts to create a localized mechanical resonator, or acoustic wave cavity 26. The '310 patent discloses an acoustic wave switch that includes a substrate with an acoustic wave cavity, or resonator, formed therein such that the mass per unit area of the acoustic cavity is greater than the mass per unit area of the substrate adjacent the acoustic cavity. A transducer is mounted on the acoustic cavity for generating an acoustic wave that is substantially trapped in the cavity. A touch on the touch surface of the acoustic wave cavity absorbs acoustic wave energy and produces a detectable change in the impedance of the transducer. Moreover, as a user touches the touch surface, the resonant frequency changes, which may be detected by the sensing circuit 40 and/or processing unit which is electrically connected to the transducer.

[0039] The acoustic wave switch 12 has a high Q (the ratio of the stored energy to lost or dissipated energy over a complete cycle) so as to enable a touch to be detected by extremely simple, low-cost circuitry. The acoustic wave switch 12 is rugged, explosion proof, operates in the presence of liquids and other contaminants, has a lower power consumption and may be incorporated and integrally formed in acoustic wave panel 22.

[0040] The acoustic wave switch 12 may be connected to an extremely simple touch detection or sensing circuit 40, such as shown and described in the '310 patent. For example, the transducer 36 may be coupled to a multiplexer that sequentially couples the transducer 36 and its associated acoustic wave switch 12 to an oscillator, as discussed in the '310 patent. Embodiments of the present invention may detect a touch on the touch surface 32 through a detected change in impedance, as described in the '310 patent. A change in impedance is detected as soon as contact is made with the touch surface 32. [0041] Optionally, embodiments of the present invention may detect a touch on the touch surface 32 by measuring the decay time of the acoustic wave within the acoustic wave cavity 26. United States Patent Application Publication No. 2004/0246239, entitled "Acoustic Wave Touch Detection Circuit and Method" (the "'239 application") which is hereby incorporated by reference in its entirety, describes a controller that detects a sensed event such as a touch on an acoustic wave switch/sensor based on the decay time. The trapped acoustic wave within the acoustic wave cavity, or resonator, acts to "ring" the acoustic cavity. That is, as a voltage is applied to the transducer, the transducer operates to resonate the acoustic cavity.

[0042] As described in the '239 application, the sensing circuit 40 operatively connected to the acoustic wave switch 12 may include a controller that drives the transducer 36 to generate a resonant acoustic wave in the acoustic wave cavity 26 during a first portion of a sampling cycle. In a second portion of the sampling cycle, the controller monitors the time that it takes for the acoustic wave signal from the transducer 36 to decay to a predetermined level. Based on the decay time, the controller detects a sensed event, such as a touch on the touch surface 32.

[0043] Figures 3 and 4 illustrate isometric, exploded front and rear views, respectively, of an overlay assembly 50, according to an embodiment of the present invention. The overlay assembly 50 is configured to be used over the acoustic wave panel 22, shown in Figure 1, for example. That is, the overlay assembly 50 is configured to be received and secured by the ridge 24 that surrounds the front face of the acoustic wave panel 22. Optionally, the overlay assembly 50 may be adhesively secured to the front face of the acoustic wave panel 22 (shown in Figures 1-2). The overlay assembly 50 includes a plurality of plastic sheets or layers. Referring to Figures 3 and 4, the overlay assembly includes an overlay face layer 52, a pocket layer 54, a film layer 56, a lamp layer 58, and a spacer layer 60.

[0044] Referring to Figure 4, in particular, the lamp layer 58 is rear-surface printed with dampener elastomeric ink at areas that are to be aligned with acoustic wave switches. As such, elastomeric dampening pads are formed on a rear-side of the lamp layer 58. While the overlay assembly 50 shown is configured with 14 touch areas that are configured to align with 14 acoustic wave switch areas, only 4 elastomeric dampening pads 62 are shown on the rear side of the lamp layer 58 in Figure 4.

[0045] Figures 5 and 6 illustrate isometric front and rear views, respectively, of the overlay assembly 50, according to an embodiment of the present invention. Referring to Figures 3-6, the overlay face layer 52, the pocket layer 54, the film layer 56, the lamp layer 58, and the spacer layer 60 are sandwiched together to form the overlay assembly 50. Each layer may sealingly engage an adjacent layer. For example, the overlay face layer 52 may be aligned with and sealed to the pocket layer 54.

[0046] The overlay face layer 52, the pocket layer 54, and the film layer 56 may be assembled together to form a first sub-assembly. The lamp layer 58 and the spacer layer 60 may be assembled together to form a second sub-assembly. Slide-in cards may be fit into the first sub-assembly, after which, the first and second subassemblies may be laminated together.

[0047] Figure 7 illustrates a front view of the overlay face layer 52, according to an embodiment of the present invention. The overlay face layer 52 includes a plurality of embossed touch areas 64 that are configured to align with the touch surfaces 32 of the acoustic wave switches 12 (as shown in Figures 1-2). Each embossed touch area 64 includes a clear card window 66. Each window 66 may be front surface printed with clear ultraviolet varnish for improved clarity of legends on slide-in cards that are configured to be positioned underneath the card windows 66. That is, the slide-in cards include markings denoting switch functions. The markings are visible through the windows 66. While 14 windows 66 are shown, more or less windows 66 may be used, depending on the type of device or component being used with the overlay assembly 50.

[0048] Each embossed touch area 64 also includes at least one light window 68 formed at a corner of the touch area 64. The light windows 68 of each touch area 64 may be distally located away from respective card windows 66. The light windows 68 are unprinted in order to allow light from light sources, such as light-emitting diodes (LEDs) to transmit therethrough and illuminate each embossed touch area 64.

[0049] More or less light windows 68 may be used than those shown in Figure 7. Further, while the light windows 68 are shown as circular, the light windows 68 may be various shapes and sizes.

[0050] The embossed touch areas 64 are embossed to provide an operator with a defined, tactile area to engage. Optionally, the touch areas 64 may not be embossed, but rather simply denote touch areas with card windows 66 and light windows 68 on a flat layer.

[0051] Figure 8 illustrates a front view of the pocket layer 54, according to an embodiment of the present invention. The perimeter of the pocket layer 54 is similar to that of the overlay face layer 52, as well as the other layers. The pocket layer 54 is configured to receive and retain slide-in cards that are configured to show through the windows 66 of the overlay face layer 52.

[0052] The pocket layer 54 includes internal channels 70 and 72 formed therethrough. The channels 70 and 72 are configured to receive and retain slide-in cards. For example, the slide-in cards may include notches around peripheral edges that are configured to secure to edges that define the channels 70 and 72. Thus, an operator may customize the slide-in cards so that they are associated with particular functions associated with each acoustic wave switch 12 (shown in Figures 1-2). Once the slide-in cards are positioned within the channels 70 and 72, the pocket layer 54 is aligned and secured to the overlay face layer 52 such that distinguishing markings on each slide-in card show through respective card windows 66. Optionally, or additionally, the slide-in cards may be secured to the film layer 56, as noted below.

[0053] Figure 9 illustrates a front view of the film layer 56, according to an embodiment of the present invention. The film layer 56 is configured to sandwich the pocket layer 54 between the film layer 56 and the overlay face layer 52. The film layer 56 includes slots 74. The slots 74 may be configured to receive and retain tabs of the slide-in cards that are configured to show through the channels 70 and 72 of the pocket layer 54, and therefore the card windows 66. While only three slots 74 are shown in Figure 9, more or less may be used, depending on the number of slide-in cards used. Thus, the slots 74 may secure the slide-in cards to a front surface of the film layer 56, by way of tabs extending from the slide-in cards. The film layer 56, with the slide-in cards secured to the front face, is then pressed into the pocket layer 54, thereby further securing the slide-in cards in place. At this point, the overlay face layer 52, the pocket layer 54, and the film layer 56 may be laminated together to form a first sub-assembly.

[0054] Additionally, adhesive may be laminated to a rear surface of the film layer 56. The adhesive may be used to secure the first sub-assembly to the second subassembly.

[0055] Figure 10 illustrates a rear view of the lamp layer 58, such as an electroluminescent lamp layer, according to an embodiment of the present invention. The lamp layer 58 includes the elastomeric dampening pads 62 secured to a rear-side thereof. The dampening pads 62 are used in conjunction with the acoustic wave switches 12 (shown in Figures 1 and 2) in order to provide a detectable touch, when the pads 62 contact the switches 12 and dampen acoustic wave energy. That is, because the dampening pads 62 are formed of an elastomeric material, such as rubber, the dampening pads, unlike conventional overlays, provide a medium that sufficiently dampens acoustic wave energy of the acoustic wave switches 12 (shown in Figures 1 and 2) when the dampening pads 62 contact the touch surfaces 32 of the switches 12.

[0056] The lamp layer 58 is configured to provide a low-level back light to the touch areas 64 of the overlay face layer 52. Each LED 80, which may be on the lamp layer 58 or on the device 10, may provide a pin-point of light that indicates key operation or status.

[0057] The lamp layer 58 and the LEDs 80 may be powered separately from internal power sources. As such, the lamp layer 58 and the LEDs 80 may be independent of each other and may be switched on and off by separate software commands. [0058] A power lead 76 may extend from a lower corner of the lamp layer 58. The power lead 76 includes power lines 78 that connect to power buses of the lamp layer 58. The power lines 78 are input into a reciprocal socket in the device 10 (shown in Figure 1) in order to supply power to the lamp layer 58.

[0059] Optionally, the areas of Figure 10 showing the LEDs 80 may be open spaces. The LEDs 80 may instead be formed on the face of the device 10 (as noted above, and as shown in Figure 12). Also, alternatively, the device 10 and the overlay assembly 50 may not include light-emitting devices.

[0060] The power buses transmit luminescence generated by LEDs, whether on the lamp layer 58, or on the device 10. Thus, when LEDs are activated, the lamp layer 58 generates light by way of electroluminescence.

[0061] Figure 11 illustrates a front view of the spacer layer 60, according to an embodiment of the present invention. The spacer layer 60 includes a plurality of openings 81 that are configured to be aligned with the dampening pads 62 of the lamp layer 58 (shown in Figure 10). In this manner, the dampening pads 62 may pass through the openings 81 and contact touch surfaces 32 of the acoustic wave switches 12 (shown in Figures 1 and 2). The spacer layer 60 is aligned with the lamp layer 58 (shown in Figure 10) and laminated together to form the second-subassembly. The first and second sub-assemblies are then laminated together to form the overlay assembly 50 (shown in Figures 3-6).

[0062] The spacer layer 60 ensures that the dampening pads 62 do not touch the touch surfaces 32 when an operator is not touching the embossed touch areas 64 of the overlay face layer 52. That is, the spacer layer 60 spaces the lamp layer 58 from the acoustic wave panel 22 (shown in Figures 1 and 2)

[0063] Figures 12 and 13 illustrate isometric, exploded front and rear views, respectively, of the device 10 having the overlay assembly 50, according to an embodiment of the present invention. As previously discussed, the overlay assembly 50 includes the first sub-assembly 82, including the overlay face layer 52, the pocket layer 54, and the film layer 56 laminated together, and the second sub-assembly 84, including the lamp layer 58 and the spacer layer 60 laminated together. The first and second subassemblies 82 and 84 are laminated to one another to form the overlay assembly 50. The overlay assembly 50 is then secured to the front face of the acoustic wave panel 12, which may include a plurality of LEDs 88 (if the lamp layer 58 does not include integral LEDs). The power lead 76 of the lamp layer 58 may pass through an opening 90 formed through the acoustic wave panel 12 and connect to a socket within the device 10.

[0064] Figure 14 illustrates an isometric front view of the device having the overlay assembly 50 secured thereon, according to an embodiment of the present invention. As shown, a plurality of cards 92, such as slide-in cards, show through the card windows 66 of the embossed touch areas 64.

[0065] Referring to Figures 1-14, in order to engage a touch surface 32 of an acoustic wave switch 12, an operator touches a desired embossed touch area 64 of the overlay face layer 52. The embossed touch area 64, including the respective window 66, then moves into the card 92 secured in place by the pocket layer 54 and the film layer 56. The card 92 is then forced into the film layer 56, thereby causing the film layer 56 to move toward a dampening pad 62 on the lamp layer 58. The dampening pad 62 then moves through an opening 81 of the spacer layer 60 and into the touch surface 32. The resulting change of absorbed energy is then detected by the sensing circuit 40.

[0066] Thus, unlike typical overlays, embodiments of the present invention provide an overlay assembly that exhibits sufficient energy absorption properties to be used in conjunction with acoustic wave switches. As noted above, it has been found that the elastomeric pads provide such energy absorption properties.

[0067] Embodiments of the present invention provide a system of colored, illuminated front surfaces for acoustic wave switches. The card windows, or areas surrounding the card windows, of the overlay face layer may be colored, and illuminated by the LEDs. [0068] The overlay assembly 50 may be formed of a screen printed plastic membrane. The main body of each layer may be formed of a thin sheet of clear plastic. For example, the main bodies of the layers may be formed of polyester or polycarbonate and laminated together with acrylic adhesives. Specialized inks are used on the cards to provide graphic features, colors, and lettering. It has been found that the dampening pads, which may be formed of the specialized elastomeric ink, enables the overlay assembly to be operated with acoustic wave switches, and even with electroluminescent backlighting.

[0069] As noted above, more or less switch areas, windows, and the like may be used than those shown. Additionally, the windows and switch areas may be in different configurations, sizes, and shapes than those shown.

[0070] The overlay assembly 50 may be configured to be removably retained by the device. For example, the overlay assembly 50 may be removably secured by the retaining ridge of the device 10. As such, the overlay assembly 50 may be secured to the acoustic wave panel 22 without being sealed thereto. Accordingly, the overlay assembly 50 may be removed at any time, and interchanged with another overlay assembly 50.

[0071] While various spatial and directional terms, such as top, bottom, lower, mid, lateral, horizontal, vertical, front and the like may used to describe embodiments of the present invention, it is understood that such terms are merely used with respect to the orientations shown in the drawings. The orientations may be inverted, rotated, or otherwise changed, such that an upper portion is a lower portion, and vice versa, horizontal becomes vertical, and the like.

[0072] Variations and modifications of the foregoing are within the scope of the present invention. It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.

[0073] Various features of the invention are set forth in the following claims.

Claims

1. An overlay assembly configured to be used with an acoustic wave panel of a device, the overlay assembly comprising:

an overlay face layer including a touch area defining a card window;

a pocket layer including a channel aligned with said touch area;

a film layer aligned with said overlay face layer and said pocket layer;

a switch card secured by at least one of said pocket layer and said film layer, wherein said switch card shows through said card window;

a lamp layer including a dampening pad aligned with said switch card and said touch area; and

a spacer layer having an opening formed therethrough, wherein said dampening pad is aligned with said opening.

2. The overlay assembly of claim 1, wherein said touch area is embossed.

3. The overlay assembly of claim 1, wherein said overlay face layer comprises at least one light window proximate said card window.

4. The overlay assembly of claim 1, wherein said film layer comprises at least one slot configured to receive and retain a tab of said switch card.

5. The overlay assembly of claim 1, wherein said lamp layer is configured to radiate light through electroluminescence.

6. The overlay assembly of claim 1, wherein said dampening pad is formed of elastomeric ink.

7. The overlay assembly of claim 1, wherein said overlay face layer, said pocket layer, said film layer, said lamp layer, and said spacer layer are sandwiched and laminated together.

8. The overlay assembly of claim 7, wherein said layers are laminated together with an acrylic adhesive.

9. The overlay assembly of claim 1, wherein said layers are formed of polyester or polycarbonate.

10. The overlay assembly of claim 1, wherein said overlay face layer, said pocket layer, and said film layer are laminated together to form a first sub-assembly, wherein said lamp layer and said spacer layer are laminated together to form a second sub-assembly, and said first sub-assembly is adhesively secured to said second subassembly.

11. The overlay assembly of claim 1, wherein said lamp layer comprises at least one light-emitting diode (LED).

12. A system comprising:

an acoustic wave panel including an acoustic wave switch having an acoustic wave cavity with a touch surface, and a transducer secured to said acoustic wave cavity opposite said touch surface, wherein said transducer is configured to generate a trapped acoustic wave within said acoustic wave cavity; and

an overlay assembly configured to overlay said acoustic wave panel, said overlay assembly comprising:

an overlay face layer including a touch area defining a card window, wherein said touch area is aligned with said touch surface of said acoustic wave cavity; a pocket layer including a channel aligned with said touch area and said touch surface;

a film layer aligned with said overlay face layer and said pocket layer; a switch card secured by at least one of said pocket layer and said film layer, wherein said switch card shows through said card window;

an electroluminescent lamp layer including a dampening pad aligned with said switch card, said touch area, and said touch surface; and

a spacer layer having an opening formed therethrough, wherein said dampening pad is aligned with said opening such that said dampening pad is configured to pass through said opening and contact said touch surface.

13. The system of claim 12, wherein said touch area is embossed.

14. The system of claim 12, wherein said overlay face layer comprises at least one light window proximate said card window.

15. The system of claim 12, wherein said film layer comprises at least one slot configured to receive and retain a tab of said switch card.

16. The system of claim 12, wherein said dampening pad is formed of elastomeric ink.

17. The system of claim 12, wherein said overlay face layer, said pocket layer, said film layer, said lamp layer, and said spacer layer are sandwiched and laminated together.

18. The system of claim 1, wherein one or both of said acoustic wave panel and/or said lamp layer comprises at least one light-emitting diode (LED).

19. An overlay assembly configured to be used with an acoustic wave panel of a device, the overlay assembly comprising:

an overlay face layer including at least one card embossed touch area defining a card window and at least one light window proximate said card window;

a pocket layer including at least one channel aligned with said at least one embossed touch area;

a film layer aligned with said overlay face layer and said pocket layer;

at least one switch card secured by at least one of said pocket layer and said film layer, wherein said at least one switch card shows through said card window;

an electroluminescent lamp layer including at least one elastomeric dampening pad aligned with said at least one switch card and said at least one embossed touch area, wherein said lamp layer is configured to radiate light through electroluminescence; and a spacer layer having at least one opening formed therethrough, wherein said at least one dampening pad is aligned with said at least one opening,

wherein said overlay face layer, said pocket layer, said film layer, said lamp layer, and said spacer layer are sandwiched and laminated together with an acrylic adhesive.

20. The overlay assembly of claim 19, wherein said at least one card embossed touch area comprises a plurality of card embossed touch areas that correspond to a number of acoustic wave switches on the acoustic wave panel, wherein said at least one dampening pad comprises a plurality of dampening pads that correspond to the number of the acoustic wave switches on the acoustic wave panel.