US4503541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled-linewidth laser source
Assignee: United States Department of the Navy
•
Filing: 1982-11-10
•
Granted: 1985-03-05
•
Expires: 2002-11-10
Abstract
Abstract Laser linewidth is controlled by reflecting a certain portion of the laser light back into the laser cavity. This control is accomplished by aligning the active layer on an electroabsorptive cell with the active layer of a semiconductor laser on a single substrate with a first waveguide therebetween. Light from the laser is guided by the first waveguide to the electroabsorptive cell whose light absorption is electronically controlled. The laser light propagates through the active region in the electroabsorptive cell and then is guided by a second waveguide to a reflection facet. The laser light is reflected by this reflection facet back through the waveguide-cell-waveguide-laser light path. The foregoing device can be formed using either a monolithic or a hybrid design.
Inventors
- 👤 Joseph F. Weller
- 👤 Lew Goldberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:53
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/06; H01S5/065; H01S5/0601; H01S5/10; H01S5/14; H01S5/02; H01S5/026
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
164 words
A controlled-linewidth laser diode source comprising: a semiconductor laser diode with a laser active region with partially reflecting first and second facets at two opposing ends thereof to form a laser cavity, a laser biasing circuit for biasing said laser diode into conduction; an electroabsorption cell with an absorption active region with a third facet on a cell wall closest to said laser diode second facet; a first light path disposed between said laser diode second facet and said electroabsorption cell third facet for conducting light passing through said facets therebetween; an electroabsorption cell bias circuit for biasing said electroabsorption cell; reflecting means for reflecting light; and a second light path disposed to conduct light from the end of said electroabsorption cell opposite to said third facet to said reflecting means; wherein an output light signal is taken from said first facet and wherein linewidth variation thereof is obtained by varying the bias applied by said electroabsorption cell bias circuit to said electroabsorption cell.
Claim 2
Dependent Claim
164 words
A controlled-linewidth laser diode source comprising: a semiconductor laser diode with a laser active region with partially reflecting first and second facets at two opposing ends thereof to form a laser cavity, a laser biasing circuit for biasing said laser diode into conduction; an electroabsorption cell with an absorption active region with a third facet on a cell wall closest to said laser diode second facet; a first light path disposed between said laser diode second facet and said electroabsorption cell third facet for conducting light passing through said facets therebetween; an electroabsorption cell bias circuit for biasing said electroabsorption cell; reflecting means for reflecting light; and a second light path disposed to conduct light from the end of said electroabsorption cell opposite to said third facet to said reflecting means; wherein an output light signal is taken from said first facet and wherein linewidth variation thereof is obtained by varying the bias applied by said electroabsorption cell bias circuit to said electroabsorption cell.
Claim 3
Dependent Claim
18 words
A laser diode source as defined in claim 1, wherein said first light path comprises an optical waveguide.
Claim 4
Dependent Claim
18 words
A laser diode source as defined in claim 2, wherein said second light path comprises an optical waveguide.
Claim 5
Dependent Claim
20 words
A laser diode source as defined in claim 3, wherein said second light path comprises a length of optical fiber.
Claim 6
Dependent Claim
25 words
A laser diode source as defined in claim 3, wherein said laser diode and said electroabsorption cell are disposed on a single monolithic semiconductor substrate.
Claim 7
Dependent Claim
45 words
A laser diode source as defined in claim 5, wherein said second facet of said laser diode and said third facet of said electroabsorption cell are in parallel alignment, and wherein said first light path between said second and third facets comprises an air space.
Claim 8
Dependent Claim
51 words
A laser diode source as defined in claim 6, wherein electroabsorptive cell end opposite to said third facet has a fourth facet formed thereon which is in parallel alignment with said reflecting means; and wherein said second light path between said fourth facet and said reflecting means comprises an air space.
Claim 9
Dependent Claim
40 words
A laser diode as defined in claim 4, further comprising means for adjusting the phase of the light propagating in the light path formed by said laser diode, said first light path, said electroabsorption cell, and said second light path.
Claim 10
Dependent Claim
175 words
A controlled-linewidth laser diode source comprising: a semiconductor substrate; a laser diode formed on said substrate, said laser diode including a laser active region with partially reflecting parallel facets at two opposing ends thereof to form a laser cavity; an electroabsorption cell formed on said substrate, said electroabsorption cell having an absorption active region with a third facet on the end of said cell closest to said laser second facet; a first light path disposed on said substrate between said laser diode second facet and said electroabsorption cell third facet for conducting light therebetween; a waveguide comprising a second light path formed on said substrate adjacent the end of said electroabsorption cell opposite to said third facet for conducting light passing through this end therethrough, said waveguide having a given length and with a fourth facet at the end thereof for reflecting light propagating in said second path waveguide back toward said electroabsorption cell and said laser diode; and appropriate contacts for applying driving currents and voltages to said laser diode and electroabsorptive cell, respectively.
Claim 11
Dependent Claim
175 words
A controlled-linewidth laser diode source comprising: a semiconductor substrate; a laser diode formed on said substrate, said laser diode including a laser active region with partially reflecting parallel facets at two opposing ends thereof to form a laser cavity; an electroabsorption cell formed on said substrate, said electroabsorption cell having an absorption active region with a third facet on the end of said cell closest to said laser second facet; a first light path disposed on said substrate between said laser diode second facet and said electroabsorption cell third facet for conducting light therebetween; a waveguide comprising a second light path formed on said substrate adjacent the end of said electroabsorption cell opposite to said third facet for conducting light passing through this end therethrough, said waveguide having a given length and with a fourth facet at the end thereof for reflecting light propagating in said second path waveguide back toward said electroabsorption cell and said laser diode; and appropriate contacts for applying driving currents and voltages to said laser diode and electroabsorptive cell, respectively.
Claim 12
Dependent Claim
27 words
A laser diode source as defined in claim 9, wherein said first light path comprises a waveguide formed on said substrate between said second and third facets.
Claim 13
Dependent Claim
42 words
A laser diode source as defined in claim 10, further comprising means for adjusting the phase of the light propagating in the light path formed by said laser diode, said first light path, said electroabsorption cell, and said second light path waveguide.
References Cited (Backward Citations)
US2915943A
Cited
US3470375A
Cited
US3331036A
Cited
US3395961A
Cited
US3454771A
Cited
US3979694A
Cited
US3999146A
Cited
US4101845A
Cited
US4093345A
Cited
US4138274A
Cited
US4237427A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-04 | 1988-09-03 | 1989-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-04 | 1992-09-03 | 1993-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-04 | 1996-09-03 | 1997-03-05 | $7700.00 | Window Closed / Lapsed |