US3786368A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Planar waveguide-type distributed feedback laser with angular tuning
Assignee: AT&T Inc
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Filing: 1972-10-20
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Granted: 1974-01-15
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Expires: 1992-10-20
Abstract
Abstract There is disclosed a distributed feedback laser made in an active thin film optical waveguide deposited on an anisotropic substrate of which the ordinary and extraordinary indices are lower than the film index. The laser is tunable by changing the direction of the pumping fringes or other spaced perturbations that produce the distributed feedback scattering with respect to the substrate optic axis. The change in direction of the pumping fringes or effective perturbation also changes the direction of propagation of laser light relative to the substrate optic axis and changes the optical fringe spacing without changing the freespace fringe spacing. Narrow-line single-mode tunable oscillation has been obtained.
Inventors
- 👤 J Bjorkholm
- 👤 C Shank
- 👤 T Sosnowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:52
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/08; H01S3/081; H01S3/083; H01S3/06; H01S3/063; H01S3/0632; H01S3/0635; H01S3/10; H01S3/102
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
138 words
A laser comprising an anisotropic substrate having an optic axis non-orthogonal to a major surface thereof, a waveguiding film adjoining said major surface and having an index of refraction higher than both indices of refraction of said substrate, one of said film and substrate including an active medium, and means for pumping said medium to establish a population inversion between energy levels in said medium with optical radiation in a directionally-oriented pattern determining an effective direction of distributed feedback scattering, said pattern of pumping radiation and the combination of said substrate and said films together providing periodic optical perturbations to yield the distributed feedback scattering, said laser including means for tuning its frequency of oscillation by changing the angle phi between the effective direction of feedback scattering and the projection of said optic axis on said major surface.
Claim 2
Dependent Claim
138 words
A laser comprising an anisotropic substrate having an optic axis non-orthogonal to a major surface thereof, a waveguiding film adjoining said major surface and having an index of refraction higher than both indices of refraction of said substrate, one of said film and substrate including an active medium, and means for pumping said medium to establish a population inversion between energy levels in said medium with optical radiation in a directionally-oriented pattern determining an effective direction of distributed feedback scattering, said pattern of pumping radiation and the combination of said substrate and said films together providing periodic optical perturbations to yield the distributed feedback scattering, said laser including means for tuning its frequency of oscillation by changing the angle phi between the effective direction of feedback scattering and the projection of said optic axis on said major surface.
Claim 3
Dependent Claim
86 words
A laser according to claim 1 in which the means for pumping the medium includes means for supplying to said medium two coherent interfering pumping beams yielding interference fringes that yield along their minimum spacing distributed feedback scattering and in which the means for tuning by changing the angle phi comprise means for changing the orientation of the fringes with respect to the projection of the substrate optic axis, comprising means for rotating the waveguiding film in a plane effective to change said angle phi .
Claim 4
Dependent Claim
107 words
A laser according to claim 1 in which the combination of the anisotropic substrate and the waveguiding film has an axis of substantially circular symmetry and includes evenly spaced perturbations in material properties of said combination, said perturbations being circularly symmetrical about said axis of symmetry, and the means for pumping the medium comprises means for supplying to said combination coherent pumping light in an elongated continous pattern illuminating an elongated region extending through the axis of symmetry between opposite edges of the film, the means for tuning the frequency by changing the angle phi comprising means for rotating the combination with respect to the elongated region.
Claim 5
Dependent Claim
19 words
A laser according to claim 3 in which the rotating means rotates the combination about the axis of symmetry.
Claim 6
Dependent Claim
95 words
An optical thin film waveguide device comprising an anisotropic substrate having an optic axis substantially parallel a major surface thereof, a waveguiding film adjoining said major surface and having an index-of-refraction higher than both indices of refraction of the substrate, one of said film and substrate including an active medium, and means for pumping said medium with optical radiation interference fringes, said optical thin film waveguide device including means for tuning its frequency of oscillation in that said pumping means includes means for changing the orientation of the fringes with respect to said optic axis.
Claim 7
Dependent Claim
95 words
An optical thin film waveguide device comprising an anisotropic substrate having an optic axis substantially parallel a major surface thereof, a waveguiding film adjoining said major surface and having an index-of-refraction higher than both indices of refraction of the substrate, one of said film and substrate including an active medium, and means for pumping said medium with optical radiation interference fringes, said optical thin film waveguide device including means for tuning its frequency of oscillation in that said pumping means includes means for changing the orientation of the fringes with respect to said optic axis.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |