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EP0213965A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Semiconductor laser devices

Assignee: Hitachi Ltd
•
Filing: 1986-09-04
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Granted: —
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Expires: 2006-09-04
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Abstract

Abstract It is possible to narrow the emission spectrum linewidth of a semiconductor laser device by coupling optically an external resonator (2) with one end surface of the semiconductor laser (l). However, the structure of the external resonator (2) should match the phase of the light emitted by the laser (l). Heretofore, this matching has been effected by adjusting the length of the external resonator (2), and hence productivity and reproducibility have not been good. According to this invention, characteristics of the external resonator (2) can be adjusted electrically to be matched with the phase of the emitted light owing to the fact that the external resonator (2) is made of a material, whose refractive index can be varied electrically. Therefore the semiconductor laser device according to this invention is very practical.

Inventors

  • 👤 Shinji Hitachi Dai-4-Kyoshinryo Sakano
  • 👤 Hiroyoshi Matsumura

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-28 21:27
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/107; H01S5/00; H01S5/10; H01S5/14; H01S5/141; H01S5/06; H01S5/062; H01S5/0625; H01S5/06255; H01S5/06256; H01S5/12; H01S5/125

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 49 words
A semiconductor laser device comprising: a semiconductor laser (l) having a pair of light emitting end surfaces, and a resonator (2) optically coupled with the semiconductor laser (l) at one of the light emitting end surfaces and made of a material, the optical property of which is electrically changeable.
Claim 2
Dependent Claim 49 words
A semiconductor laser device comprising: a semiconductor laser (l) having a pair of light emitting end surfaces, and a resonator (2) optically coupled with the semiconductor laser (l) at one of the light emitting end surfaces and made of a material, the optical property of which is electrically changeable.
Claim 3
Dependent Claim 32 words
A semiconductor laser device according to Claim l, in which said semiconductor laser (l) and said resonator (2) are formed in a monolithic form on a compound semiconductor crystal substrate (l4, 27).
Claim 4
Dependent Claim 25 words
A semiconductor laser device according to Claim 2, in which said resonator (2) includes an area for regulating electrically the intensity of light passing therethrough.
Claim 5
Dependent Claim 16 words
A semiconductor laser device according to Claim l, in which said material has an electro-optical effect.
Claim 6
Dependent Claim 15 words
A semiconductor laser device according to Claim l, wherein said optical property is refractive index.
Claim 7
Dependent Claim 21 words
A semiconductor laser device according to Claim 5, wherein said laser (l) and said resonator (2) are aligned end to end.
Claim 8
Dependent Claim 25 words
A semiconductor laser device according to claim 6, wherein said laser (l) and said resonator (2) are mainly formed of a same III-V compound material.
Claim 9
Dependent Claim 28 words
A semiconductor laser device according to claim 7, wherein said resonator (2) includes a reflection mirror (9) at the opposite end to that coupled to said laser (l).

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