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US4686678A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor laser apparatus with isolator

Assignee: NEC Corp
•
Filing: 1985-03-25
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Granted: 1987-08-11
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Expires: 2005-03-25
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Abstract

Abstract The apparatus includes a semiconductor laser diode, a mounting for the laser diode and a casing with a window through which light from the diode passes. The casing hermetically seals the diode. A magneto-optical member is provided between the end face of the laser diode and the window. The magneto-optical member has a spontaneous magnetization oriented in the direction of the light transmission and a magnetic field is applied to saturate the magneto-optical member.

Inventors

  • 👤 Yoshinori Ohta
  • 👤 Isamu Sakuma
  • 👤 Taketoshi Hibiya
  • 👤 Mitsuhito Sakaguchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:24
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/09; G02F1/093; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4204; G02B6/4207; G02B6/4208; H; H01; H01S; H01S5/00; H01S5/02; H01S5/022; H01S5/0225; H01S5/02257; H01S5/005; H01S5/0064; Y; Y10; Y10S; Y10S372/00; Y10S372/703

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 131 words
A semiconductor laser apparatus with an optical isolation function comprising: a semiconductor laser diode; means for mounting said semiconductor laser diode; a casing with a window through which oscillation light from said semiconductor laser diode passes, for hermetically sealing said semiconductor laser diode; a magneto-optical member, provided between an end face of said semiconductor laser diode and said window, and having spontaneous magnetization oriented in the direction of said oscillation light transmission, for polarizing oscillation light that is reflected back to said laser diode through said window at 90° with respect to said oscillation light that passes through said window from said laser diode; and means for applying a magnetic field in the direction of said oscillation light transmission in a manner to saturate the spontaneous magnetization of said magneto-optical member.
Claim 2
Dependent Claim 131 words
A semiconductor laser apparatus with an optical isolation function comprising: a semiconductor laser diode; means for mounting said semiconductor laser diode; a casing with a window through which oscillation light from said semiconductor laser diode passes, for hermetically sealing said semiconductor laser diode; a magneto-optical member, provided between an end face of said semiconductor laser diode and said window, and having spontaneous magnetization oriented in the direction of said oscillation light transmission, for polarizing oscillation light that is reflected back to said laser diode through said window at 90° with respect to said oscillation light that passes through said window from said laser diode; and means for applying a magnetic field in the direction of said oscillation light transmission in a manner to saturate the spontaneous magnetization of said magneto-optical member.
Claim 3
Dependent Claim 15 words
An apparatus as set forth in claim 1, wherein said magneto-optical member comprises a crystal.
Claim 4
Dependent Claim 24 words
An apparatus as set forth in claim 2, wherein said crystal has a composition of Gb 3-x Bi x Fe 5 O 12 .
Claim 5
Dependent Claim 27 words
An apparatus as set forth in claim 1, wherein said magneto-optical member is set to provide 45° of Faraday rotation to light emitted from said laser diode.
Claim 6
Dependent Claim 19 words
An apparatus as set forth in claim 1, wherein said magneto-optical element comprises a garnet film on said window.
Claim 7
Dependent Claim 25 words
An apparatus as set forth in claim 5, wherein said garnet film has a composition of Bi x Y 3-x Fe 5 O 12 .
Claim 8
Dependent Claim 33 words
An apparatus as set forth in claim 5, wherein said garnet film has a composition of R 3 Fe 5 S 7 .5 O 4 .5 where R is a rare earth atom.
Claim 9
Dependent Claim 22 words
An apparatus as set forth in claim 1, wherein said magneto-optical member comprises a garnet film connected to said semiconnector laser diode.
Claim 10
Dependent Claim 32 words
An apparatus as set forth in claim 8, including a dielectric film provided over one end face of said semiconnector laser diode, said garnet film being provided directly over said dielectric film.

References Cited (Backward Citations)

US3840889A Cited
US4375910A Cited
US4540284A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-08-10 1991-02-09 1991-08-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-08-10 1995-02-09 1995-08-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-08-10 1999-02-09 1999-08-11 $7700.00 Window Closed / Lapsed

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