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EP0065818A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Phase-locked semiconductor laser device

Assignee: Hitachi Ltd
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Filing: 1982-04-22
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Granted: —
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Expires: 2002-04-22
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Abstract

Abstract A phase-locked semiconductor laser device comprising a laminated structure in which the active regions are vertically arrayed and comprise a plurality of first semiconductor layers (3, 5, 7) having substantially the same composition as each other, stacked so as to be sandwiched between second semiconductor layers (2,4,6,8,) having a band gap wider, and a refractive index lower, than those of said first semiconductor layers, forming cladding layers. A third semiconductor layer (9) is disposed in contact with at least one of the side faces of said laminated structure (2 - 8) parallel to the direction of travel of a laser beam, and is not narrower in band gap and not higher in the refractive index than said first semiconductor layers (3,5,7) and does not have the same conductivity type as, at least, that of said first semiconductor layers. Electrodes (10, 11) inject current into an interface between said first semiconductor layers (3, 5, 7) and said third semiconductor layer (9). Cleaved faces (12,12') act as an optical resonator for the laser beam. Laser beams from the plurality of active regions have coherent wavelengths and phases, and a high optical output.

Inventors

  • 👤 Hisao Nakashima
  • 👤 Jun-Ichi Umeda
  • 👤 Hiroshi Matsuda
  • 👤 Takao Kuroda
  • 👤 Takashi Kajimura

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-30 20:04
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/2203; H01S5/40; H01S5/4025; H01S5/4031; H01S5/4043; H01S5/04; H01S5/042; H01S5/0421; H01S5/0422; H01S5/0424; H01S5/227; H01S5/2275

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 60 words
A semiconductor laser device comprising a plurality active regions (3,5,7,13); cladding layers (2,4,6,8,14) sandwiching the active regions; and means (9,9',10,10',11, 22,23) for injecting current into the active regions to cause laser action therein; characterised in that at least two active regions are in the form of layers (3,5,7) vertically arrayed one over another, with a cladding layer (4,6) between them.
Claim 2
Dependent Claim 60 words
A semiconductor laser device comprising a plurality active regions (3,5,7,13); cladding layers (2,4,6,8,14) sandwiching the active regions; and means (9,9',10,10',11, 22,23) for injecting current into the active regions to cause laser action therein; characterised in that at least two active regions are in the form of layers (3,5,7) vertically arrayed one over another, with a cladding layer (4,6) between them.
Claim 3
Dependent Claim 183 words
A semiconductor laser device as defined in claim 1 comprising a laminated structure in which said active regions are a plurality of first semiconductor layers (3,5,7,13) having substantially the same composition as each other stacked so as to be sandwiched between second semiconductor layers (2,4,6,8,14) which are wider in band gap, and which are lower in refractive index, than those of said first semiconductor layers; a third semiconductor layer (9,9') which is disposed in contact with at least one of the side faces of said laminated structure parallel to the direction of travel of a laser beam, the third semiconductor layer being not narrower in band gap and not higher in refractive index than said first semiconductor layers and not having the same conductivity type as, at least, that of said first semiconductor layers; said current injection means (10,10',11,22,23) being arranged to inject current into an interface between said first semiconductor layers (3,5,7,13) and said third semiconductor layer (9,9') disposed on the side face of said laminated structure; the device including means (12,12') to act as an optical resonator for the laser beam.
Claim 4
Dependent Claim 41 words
A semiconductor laser device as defined in claim 1, wherein there are said third semiconductor layers (9,9') disposed on both the opposing side faces of said laminated structure (2 - 8) parallel to the direction of travel of the laser beam.
Claim 5
Dependent Claim 44 words
A semiconductor laser device as defined in claim 2 or 3, wherein facets (16,16') of a region emitting the laser beam in said laminated structure (2 - 8) have a conductivity type opposite to that of the other part (15) of said laminated structure.
Claim 6
Dependent Claim 34 words
A semiconductor laser device as defined in any of claims 2 to 4, wherein said laminated structure (2 - 8) and said third semiconductor layer (9,9') are formed on a semi-insulating semiconductor substrate (1).
Claim 7
Dependent Claim 35 words
A semiconductor laser device as defined in any of claims 2 to 4, wherein at least said laminated structure (2 - 8) is disposed on a semi-insulating semiconductor layer (20) over a semiconductor substrate (31).

References Cited (Backward Citations)

US3514715A Cited
US4121177A Cited
FR2461380A1 Cited

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