EP0416195A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor laser device
Assignee: Mitsubishi Electric Corp
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Filing: 1990-01-17
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Granted: —
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Expires: 2010-01-17
Abstract
Abstract A semiconductor laser device comprises a semiconductor laser light emitting element (1), and a cap (5) that covers and hermetically seals the laser light emitting element. Laser light emitted from the element goes out through a hole formed in the top wall of the cap (5). Reflected light blocking means is disposed in the hole in the top wall of the cap. The reflected light blocking means comprises a twisted-nematic liquid crystal cell and a pair of polarizers (61,62) between which the twisted-nematic liquid crystal cell (7) is disposed.
Inventors
- 👤 Katsuhisa C/O Mitsubishi Denki K.K. Tada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 04:57
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/005; H01S3/0064; G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4204; G02B6/4207; G02B6/4208
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
78 words
A semiconductor laser device comprising: a laser element which emits laser light; a cap covering and hermetically sealing said laser element. said cap having, in its top wall, a hole through which laser light is emitted; and reflected light blocking means disposed in said hole in said top wall of said cap; wherein said reflected light blocking means comprises a twisted-nematic liquid crystal cell and a pair of polarizers between which said twisted-nematic liquid crystal cell is disposed.
Claim 2
Dependent Claim
78 words
A semiconductor laser device comprising: a laser element which emits laser light; a cap covering and hermetically sealing said laser element. said cap having, in its top wall, a hole through which laser light is emitted; and reflected light blocking means disposed in said hole in said top wall of said cap; wherein said reflected light blocking means comprises a twisted-nematic liquid crystal cell and a pair of polarizers between which said twisted-nematic liquid crystal cell is disposed.
Claim 3
Dependent Claim
46 words
A semiconductor laser devioe according to Claim 1 wherein said twisted-nematic liquid crystal cell rotates the plane of polarization of laser light by 45° as laser light passes through said cells and the directions of polarization of said polarizers are at 45° relative to each other.
Claim 4
Dependent Claim
13 words
A semiconductor laser device according to Claim 1 wherein said polarizers comprise calcite.
Claim 5
Dependent Claim
13 words
A semiconductor laser device according to Claim 2 wherein said polarizers comprises calcite.
References Cited (Backward Citations)
No citation records indexed.
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