US3729250A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acousto-optic filter having means for damping acoustic resonances and stray light
Assignee: HP Inc
•
Filing: 1971-07-23
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Granted: 1973-04-24
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Expires: 1991-07-23
Abstract
Abstract Acoustic resonances in the acoustically excited photoelastic optically birefringent crystal of an acousto-optic filter are damped by coating the side of the photoelastic crystal with an acoustic absorbing medium, such as tungsten powder loaded epoxy, whereby undesired acoustic resonances are damped. The acoustic impedance of the coating preferably matches the acoustic impedance of the crystal. The outside surface of the crystal is preferably cleaned and roughened to assure an intimate bond between the absorbing material and the crystal medium.
Inventors
- 👤 L Hubby
- 👤 J Kusters
- 👤 D Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:24
CPC Classifications
G; G10; G10K; G10K11/00; G10K11/002; G02; G02F; G02F1/00; G02F1/01; G02F1/11; G02F1/116
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
88 words
An acousto-optic filter comprising a photoelastic birefringent crystal, means for directing a polarized beam of light through said photoelastic birefringent crystal, means for directing an acoustic wave collinearly with the polarized beam of light through said photoelastic birefringent crystal to shift a portion of the polarized beam of light from a first polarization to an orthogonal second polarization, and a single coating comprising a mixture of acoustic and light energy absorbing material on the sides of said photoelastic birefringent crystal to damp undesired acoustic resonances and stray light.
Claim 2
Dependent Claim
88 words
An acousto-optic filter comprising a photoelastic birefringent crystal, means for directing a polarized beam of light through said photoelastic birefringent crystal, means for directing an acoustic wave collinearly with the polarized beam of light through said photoelastic birefringent crystal to shift a portion of the polarized beam of light from a first polarization to an orthogonal second polarization, and a single coating comprising a mixture of acoustic and light energy absorbing material on the sides of said photoelastic birefringent crystal to damp undesired acoustic resonances and stray light.
Claim 3
Dependent Claim
26 words
An acousto-optic filter as in claim 1 wherein said coating of acoustic and light energy absorbing material comprises an epoxy adhesive loaded with particles of tungsten.
References Cited (Backward Citations)
US2392350A
Cited
US3572897A
Cited
US3614201A
Cited
US3637288A
Cited
US3632193A
Cited
US3644015A
Cited
US3653743A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |