Patent US4450542A successfully refreshed from Google Patents.
US4450542A
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US
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Multiple beam lens transducer for sonar systems
Assignee: Litton Marine Systems Inc
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Filing: 1982-03-05
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Granted: 1984-05-22
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Expires: 2002-03-05
Abstract
Abstract A compact apparatus for transmitting and receiving multiple sonar beams utilizes an acoustic lens to direct plane waves incident in desired directions to electroacoustic transducers positioned on spherical shell segments centered in the focal regions of the lens associated with the incident beams. The electroacoustic transducers transmit spherical waves that are transformed by the acoustic lens to plane waves emergent in the desired directions.
Inventors
- 👤 Jacob A. Kritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:04
CPC Classifications
G; G10; G10K; G10K11/00; G10K11/004; G10K11/18; G10K11/26; G10K11/30
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
114 words
An apparatus for transmitting and receiving a plurality of sonar beams comprising: lens means having a central axis and a focal surface, for converting incident plane sound waves to sound waves that converge at a focal region in said focal surface such that plane waves incident in different predetermined directions converge to different focal regions, and for converting sound waves emitted from said focal regions to plane sound waves radiating from said lens means in said predetermined directions, and a plurality of electroacoustic transducers, configured as segments of spherical shells, said spherical shells having centers in said focal regions, said transducers disposed between said lens means and said centers to receive focused sound waves.
Claim 2
Independent Claim
114 words
An apparatus for transmitting and receiving a plurality of sonar beams comprising: lens means having a central axis and a focal surface, for converting incident plane sound waves to sound waves that converge at a focal region in said focal surface such that plane waves incident in different predetermined directions converge to different focal regions, and for converting sound waves emitted from said focal regions to plane sound waves radiating from said lens means in said predetermined directions, and a plurality of electroacoustic transducers, configured as segments of spherical shells, said spherical shells having centers in said focal regions, said transducers disposed between said lens means and said centers to receive focused sound waves.
Claim 3
Dependent Claim
67 words
Apparatus as described in claim 1 wherein said lens means includes a doubly concave acoustic lens constructed of a material with an acoustic propagating velocity that is greater than the acoustic propagating velocity of water, and an acoustic propagating medium having an acoustic propagating velocity that is less than said acoustic propagating velocity of said lens material, positioned between said lens and said plurality of acoustic transducers.
Claim 4
Dependent Claim
57 words
Apparatus as described in claim 2 further including: window means positioned between said transducers and said acoustic propagating medium, for transmitting acoustic signals, transporting heat, and providing structural strength, and matching means positioned between said window means and said acoustic propagating medium for providing an acoustic impedance match between said window means and said acoustic propagating medium.
Claim 5
Dependent Claim
16 words
Apparatus as described in claim 3 wherein said doubly concave acoustic lens is comprised of polystyrene.
Claim 6
Dependent Claim
16 words
Apparatus as described in claim 4 wherein said acoustic propagating medium is comprised of silicone rubber.
Claim 7
Dependent Claim
64 words
Apparatus as described in claim 5 wherein said window means is comprised of a plurality of spherical shell segments having thicknesses that are an integral multiple of a half wavelength of an incident sound wave, and said matching means is comprised of a plurality of spherical shell segments having thicknesses that are an odd multiple of a quarter wavelength of said incident sound wave.
Claim 8
Dependent Claim
14 words
Apparatus as described in claim 6 wherein said window means is comprised of metal.
Claim 9
Dependent Claim
14 words
Apparatus as described in claim 7 wherein said matching means is comprised of plastic.
Claim 10
Dependent Claim
13 words
Apparatus as described in claim 8 wherein said metal is comprised of aluminum.
Claim 11
Dependent Claim
13 words
Apparatus as described in claim 9 wherein said plastic is comprised of epoxy.
Claim 12
Dependent Claim
27 words
Apparatus as described in claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wherein each of said transducers is comprised of a piezoelectric crystal.
Claim 13
Dependent Claim
26 words
Apparatus as described in claim 11 wherein said piezoelectric crystals are three in number, each positioned 15 degrees off said central axis of said lens means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-22 | 1987-11-21 | 1988-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-22 | 1991-11-21 | 1992-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-22 | 1995-11-21 | 1996-05-22 | $7700.00 | Window Closed / Lapsed |