US5708461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic touch position sensor using a low-loss transparent substrate
Assignee: Elo Touch Solutions Inc
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Filing: 1995-01-24
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Granted: 1998-01-13
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Expires: 2015-01-24
Abstract
Abstract A touch position sensor or "touchscreen" utilizes acoustic waves within a sensor substrate to determine the position of touch. The substrate is made of a transparent material, such as borosilicate glass or a barium glass, which exhibits substantially less acoustic absorption than soda-lime glass.
Inventors
- 👤 Joel Kent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:40
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/043; G06F3/0436; G06F3/0416
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
116 words
In a touch sensor comprising: a substrate capable of propagating acoustic waves along a plurality of acoustic paths and having at least one touch-sensitive surface, a touch on said surface causing a perturbation of said acoustic waves; at least one transmitting transducer coupled to said substrate for producing acoustic waves therein; and means coupled to said substrate for sensing a touch-induced perturbation of said acoustic waves; wherein Rayleigh waves are propagated along at least a portion of said acoustic paths; the improvement wherein a touch-induced pertubation of Rayleigh waves is sensed by said sensing means and said substrate is made of a glass selected from the group consisting of a borosilicate glass and a barium-containing glass.
Claim 2
Dependent Claim
116 words
In a touch sensor comprising: a substrate capable of propagating acoustic waves along a plurality of acoustic paths and having at least one touch-sensitive surface, a touch on said surface causing a perturbation of said acoustic waves; at least one transmitting transducer coupled to said substrate for producing acoustic waves therein; and means coupled to said substrate for sensing a touch-induced perturbation of said acoustic waves; wherein Rayleigh waves are propagated along at least a portion of said acoustic paths; the improvement wherein a touch-induced pertubation of Rayleigh waves is sensed by said sensing means and said substrate is made of a glass selected from the group consisting of a borosilicate glass and a barium-containing glass.
Claim 3
Dependent Claim
27 words
The touch sensor according to claim 1, wherein said means for sensing a touch-induced perturbation comprises means for determining the position of a touch on said surface.
Claim 4
Dependent Claim
72 words
The touch sensor according to claim 2, wherein said acoustic waves traverse an area of said substrate having a plurality of regions, said regions each having a characteristic period of delay in the time of traverse of said waves, a touch on said surface in a given region perturbing said acoustic waves at said characteristic delay period, and wherein said means for sensing touch-induced perturbation comprises means for determining said delay period.
Claim 5
Dependent Claim
38 words
The touch sensor according to claim 3, wherein said means for sensing touch induced perturbation includes at least one receiving transducer coupled to said substrate for producing electrical signals in response to the receipt of said acoustic waves.
Claim 6
Dependent Claim
37 words
The touch sensor according to claim 4, wherein said means for sensing touch induced perturbation includes electronic analyzer means, coupled to said receiving transducer, for processing said electrical signals to determine said touch position on said sensor.
Claim 7
Dependent Claim
34 words
The touch sensor according to claim 1, further comprising an electronic controller having an electronic driver means, coupled to said transmitting transducer, for producing an electrical oscillating signal burst to activate said transmitting transducer.
Claim 8
Dependent Claim
17 words
The touch sensor according to claim 6, wherein said electronic driver means includes a TTL output stage.
Claim 9
Dependent Claim
36 words
The touch sensor according to claim 3, further comprising means arranged on said substrate for diverting said acoustic waves produced by a single transmitting transducer into a plurality of paths extending across said plurality of regions.
Claim 10
Dependent Claim
61 words
The touch sensor according to claim 8, wherein said diverting means comprises at least one first linear array of diverting elements for diverting acoustic waves at an angle of about 90° with respect to the axis of propagation thereof as produced by said single transmitting transducer, said first linear array having a central axis substantially aligned with said axis of propagation.
Claim 11
Dependent Claim
48 words
The touch sensor according to claim 9, wherein said substrate is generally rectangular in shape, in face view, and has four substantially straight edges, and wherein said first array is disposed on said surface with its central axis substantially parallel and adjacent to an edge of said substrate.
Claim 12
Dependent Claim
37 words
The touch sensor according to claim 10, wherein said transmitting transducer produces acoustic waves with a prescribed beam width and wherein said first array has a width which is less than one half of said beam width.
Claim 13
Dependent Claim
18 words
The touch sensor according to claim 9, wherein said diverting elements of said first array are reflective elements.
Claim 14
Dependent Claim
75 words
The touch sensor according to claim 10, further comprising at least one second linear array of diverting elements disposed on said surface and having a central axis substantially parallel and adjacent to an edge of said substrate which is opposite to the edge adjacent to said first array, said second array diverting said acoustic waves at an angle of about 90° with respect to the direction of propagation thereof as determined by said first array.
Claim 15
Dependent Claim
37 words
The touch sensor according to claim 13, wherein said transmitting transducer produces acoustic waves with a prescribed beam width and wherein said second array has a width which is less than one half of said beam width.
Claim 16
Dependent Claim
18 words
The touch sensor according to claim 13, wherein said diverting elements of said second array are reflective elements.
Claim 17
Dependent Claim
35 words
The touch sensor according to claim 1, wherein said substrate is generally rectangular in shape, in face view, and has four substantially straight edges, the diagonal dimension of said substrate being greater than 21 inches.
Claim 18
Dependent Claim
33 words
The touch sensor according to claim 9, wherein said diverting elements of said first array convert acoustic energy in one type of acoustic wave to acoustic energy in another type of acoustic wave.
Claim 19
Dependent Claim
14 words
The touch sensor according to claim 1, wherein said transmitting transducer produces Rayleigh waves.
Claim 20
Dependent Claim
14 words
The touch sensor according to claim 1, wherein said transmitting transducer produces Lamb waves.
Claim 21
Dependent Claim
14 words
The touch sensor according to claim 1, wherein said transmitting transducer produces shear waves.
Claim 22
Dependent Claim
33 words
The touch sensor according to claim 13, wherein said diverting elements of said second array convert acoustic energy in one type of acoustic wave to acoustic energy in another type of acoustic wave.
Claim 23
Dependent Claim
14 words
The touch sensor according to claim 4, wherein said receiving transducer receives Rayleigh waves.
Claim 24
Dependent Claim
14 words
The touch sensor according to claim 4, wherein said receiving transducer receives Lamb waves.
Claim 25
Dependent Claim
14 words
The touch sensor according to claim 4, wherein said receiving transducer receives shear waves.
Claim 26
Dependent Claim
39 words
The touch sensor according to claim 1, wherein said transmitting transducer is a wedge transducer bonded to said substrate surface with a bonding footprint, said bonding footprint on said substrate being narrower than four wavelengths of said acoustic waves.
Claim 27
Dependent Claim
39 words
The touch sensor according to claim 2, wherein said means for sensing a touch induced perturbation includes at least one receiving transducer coupled to said substrate for producing electrical signals in response to the receipt of said acoustic waves.
Claim 28
Dependent Claim
28 words
The touch tensor according to claim 26, wherein at least one of said transmitting transducer and said receiving transducer is a wedge transducer arranged on said substrate surface.
Claim 29
Dependent Claim
20 words
The touch sensor according to claim 27, wherein all of said transducers are wedge transducers arranged on said substrate surface.
Claim 30
Dependent Claim
28 words
The touch sensor according to claim 26, wherein at least one of said transmitting transducer and said receiving transducer is a flat transducer arranged on said substrate surface.
Claim 31
Dependent Claim
20 words
The touch sensor according to claim 29, wherein all of said transducers are flat transducers arranged on said substrate surface.
Claim 32
Dependent Claim
30 words
The touch sensor according to claim 26, wherein at least one of said transmitting transducer and said receiving transducer is an edge transducer arranged on an edge of said substrate.
Claim 33
Dependent Claim
22 words
The touch sensor according to claim 31, wherein all of said transducers are edge transducers arranged on an edge of said substrate.
Claim 34
Dependent Claim
32 words
The touch sensor according to claim 1, wherein said substrate has an outer edge and wherein said sensor further comprises a seal disposed in contact with said surface adjacent said outer edge.
Claim 35
Dependent Claim
21 words
The touch sensor according to claim 33, wherein said seal causes an acoustic wave energy loss of at least 6 dB.
Claim 36
Dependent Claim
21 words
The touch sensor according to claim 34, wherein said seal causes an acoustic wave energy loss of at least 12 dB.
Claim 37
Dependent Claim
21 words
A touch sensor according to claim 1, wherein said substrate has an optical coating on said surface to substantially eliminate reflection.
Claim 38
Dependent Claim
16 words
A touch sensor according to claim 36, wherein said optical coating is a layer of plastic.
Claim 39
Dependent Claim
12 words
A touch sensor according to claim 1, wherein said substrate is frosted.
Claim 40
Dependent Claim
14 words
A touch sensor according to claim 1, wherein said substrate is curved in profile.
Claim 41
Dependent Claim
23 words
A touch sensor according to claim 13, having two transmitting transducers, one for each axis, and two receiving transducers, one for each axis.
Claim 42
Dependent Claim
36 words
A touch sensor according to claim 13, having three transmitting transducers, two for one axis, and one for the other axis, and three receiving transducers, two for said one axis and one for said other axis.
Claim 43
Dependent Claim
36 words
A touch sensor according to claim 1, having four transmitting transducers, two for one axis, and two for the other axis, and four receiving transducers, two for said one axis, and two for said other axis.
Claim 44
Dependent Claim
24 words
A touch sensor according to claim 1, further comprising a table top, and wherein said substrate forms a surface portion of said table top.
Claim 45
Dependent Claim
23 words
A touch sensor according to claim 43, wherein said substrate is frosted and further comprising means for projecting an image onto said substrate.
Claim 46
Dependent Claim
17 words
A touch sensor according to claim 38, further comprising means for projecting an image onto said substrate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-01-12 | 2001-07-14 | 2002-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-12 | 2005-07-14 | 2006-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-12 | 2009-07-14 | 2010-01-13 | $7700.00 | Window Closed / Lapsed |