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US5361271A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor laser

Assignee: Sharp Corp
•
Filing: 1993-09-13
•
Granted: 1994-11-01
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Expires: 2013-09-13
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Abstract

Abstract A semiconductor laser of the present invention includes: a semiconductor substrate, a multi-layered structure formed on the semiconductor substrate and a current and light confining section formed on the multi-layered structure, wherein the current and light confining section includes at least two multi-layered current and light confining portions each having a laser beam transmission layer and a laser beam absorption layer formed on the laser beam transmission layer, and at least one stripe groove which spatially separates the at least two current and light confining portions; wherein an equivalent refractive index in the multi-layered current and light confining portions with respect to a laser beam in a fundamental transverse mode is made smaller than that within the stripe groove; wherein the multi-layered structure includes an active layer, and the active layer has a region positioned below the stripe groove of the current and light confining section and regions positioned below a respective one of the multi-layered current and light confining portions; and wherein a optical confinement factor Γ of the active layer outside the stripe groove with respect to a laser beam in a guide mode is larger than that outside the stripe groove with respect to a laser beam in an anti-guide mode.

Inventors

  • 👤 Haruhisa Takiguchi
  • 👤 Kazuhiko Inoguchi
  • 👤 Hiroaki Kudo
  • 👤 Satoshi Sugahara
  • 👤 Mototaka Taneya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 04:30
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/223; H01S5/2231; H01S5/2004; H01S5/2205; H01S5/2206; H01S5/2232; H01S5/30; H01S5/32; H01S5/323; H01S5/32308; H01S5/32316

Claims Analysis

Total Claims: 26
Claim 1
Independent Claim 200 words
A semiconductor laser comprising a semiconductor substrate, a multi-layered structure formed on the semiconductor substrate and a current and light confining means formed on the multi-layered structure, wherein the current and light confining means includes at least two multi-layered current and light confining portions each having a laser beam transmission layer and a laser beam absorption layer formed on the laser beam transmission layer, and at least one stripe groove which spatially separates the at least two current and light confining portions; wherein an equivalent refractive index in the multi-layered current and light confining portions with respect to a laser beam in a fundamental transverse mode is made smaller than that within the stripe groove; wherein the multi-layered structure includes an active layer, and the active layer has a region positioned below the stripe groove of the current and light confining means and regions positioned below a respective one of the multi-layered current and light confining portions; and wherein an optical confinement factor Γ of the active layer outside the stripe groove with respect to a laser beam in a guide mode is larger than that outside the stripe groove with respect to a laser beam in an anti-guide mode.
Claim 2
Dependent Claim 200 words
A semiconductor laser comprising a semiconductor substrate, a multi-layered structure formed on the semiconductor substrate and a current and light confining means formed on the multi-layered structure, wherein the current and light confining means includes at least two multi-layered current and light confining portions each having a laser beam transmission layer and a laser beam absorption layer formed on the laser beam transmission layer, and at least one stripe groove which spatially separates the at least two current and light confining portions; wherein an equivalent refractive index in the multi-layered current and light confining portions with respect to a laser beam in a fundamental transverse mode is made smaller than that within the stripe groove; wherein the multi-layered structure includes an active layer, and the active layer has a region positioned below the stripe groove of the current and light confining means and regions positioned below a respective one of the multi-layered current and light confining portions; and wherein an optical confinement factor Γ of the active layer outside the stripe groove with respect to a laser beam in a guide mode is larger than that outside the stripe groove with respect to a laser beam in an anti-guide mode.
Claim 3
Dependent Claim 30 words
A semiconductor laser according to claim 1, wherein the multi-layered current and light confining portions further include another laser beam transmission layer formed adjacent to the laser beam absorption layers.
Claim 4
Dependent Claim 43 words
A semiconductor laser according to claim 1, wherein a refractive index in the laser beam transmission layer is smaller than the equivalent refractive index in the multi-layered current and light confining portions with respect to the laser beam in the fundamental transverse mode.
Claim 5
Dependent Claim 59 words
A semiconductor laser according to claim 2, wherein at least either one of the refractive index of the laser beam transmission layer or the equivalent refractive index of the another laser beam transmission layer is smaller than the equivalent refractive index in the multi-layered current and light confining portions with respect to the laser beam in the fundamental mode.
Claim 6
Dependent Claim 43 words
A semiconductor laser according to claim 1, wherein a band gap of the laser beam transmission layer is larger than that of the active layer, and a band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 7
Dependent Claim 52 words
A semiconductor laser according to claim 2, wherein any of the band gap of the laser beam transmission layer and the another laser beam transmission layer is larger than that of the active layer, and the band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 8
Dependent Claim 52 words
A semiconductor laser according to claim 4, wherein any of the band gap of the laser beam transmission layer and the another laser beam transmission layer is larger than that of the active layer, and the band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 9
Dependent Claim 43 words
A semiconductor laser according to claim 1, wherein a thickness of the laser beam absorption layer is equal to or less than 1/2 of a reciprocal of an absorption coefficient of the laser beam absorption layer with respect to a laser lasing wavelength.
Claim 10
Dependent Claim 34 words
A semiconductor laser according to claim 1, wherein the thickness of the laser beam absorption layer is equal to or less than a diffusion length of minority carriers in the laser beam absorption layer.
Claim 11
Dependent Claim 87 words
A semiconductor laser according to claim 1, wherein the multi-layered structure, the laser beam transmission layer, and the laser beam absorption layer are Al x Ga 1-x As layers; and wherein a mole fraction x of the laser beam transmission layer is set so that an optical confinement factor Γ of the active layer outside the strip groove with respect to the laser beam in the guide mode is made larger than that outside the stripe groove with respect to the laser beam in the anti-guide mode.
Claim 12
Dependent Claim 93 words
A semiconductor laser according to claim 1, wherein the multi-layered structure, the laser beam transmission layer, and the laser beam absorption layer are (Al x Ga 1-x ) 0 .5 In 0 .5 P layers; and wherein a mole fraction x of the laser beam transmission layer is set so that an optical confinement factor Γ of the active layer outside the stripe groove with respect to the laser beam in the guide mode is made larger than that outside the stripe groove with respect to the laser beam in the anti-guide mode.
Claim 13
Dependent Claim 214 words
A semiconductor laser comprising a semiconductor substrate, a current and light confining means formed on the semiconductor substrate, and a multi-layered structure formed on the current and light confining means, wherein the current and light confining means includes at least two multi-layered current and light confining portions having a laser beam absorption layer and a laser beam transmission layer formed on the laser beam absorption layer, and at least one strip groove which spatially separates the current and light confining portions; wherein an equivalent refractive index in the multi-layered current and light confining portions with respect to a laser beam in a fundamental transverse mode is made smaller than that within the stripe groove; wherein the multi-layered structure includes an active layer, and the active layer has a region positioned above the stripe groove of the current and light confining means and regions positioned above a respective one of the multi-layered current and light confining means and regions positioned above a respective one of the multi-layered current and light confining portions; and wherein an optical confinement factor Γ of the active layer outside the stripe groove with respect to a laser beam in a guide mode is larger than that outside the stripe groove with respect to a laser beam in an anti-guide mode.
Claim 14
Dependent Claim 214 words
A semiconductor laser comprising a semiconductor substrate, a current and light confining means formed on the semiconductor substrate, and a multi-layered structure formed on the current and light confining means, wherein the current and light confining means includes at least two multi-layered current and light confining portions having a laser beam absorption layer and a laser beam transmission layer formed on the laser beam absorption layer, and at least one strip groove which spatially separates the current and light confining portions; wherein an equivalent refractive index in the multi-layered current and light confining portions with respect to a laser beam in a fundamental transverse mode is made smaller than that within the stripe groove; wherein the multi-layered structure includes an active layer, and the active layer has a region positioned above the stripe groove of the current and light confining means and regions positioned above a respective one of the multi-layered current and light confining means and regions positioned above a respective one of the multi-layered current and light confining portions; and wherein an optical confinement factor Γ of the active layer outside the stripe groove with respect to a laser beam in a guide mode is larger than that outside the stripe groove with respect to a laser beam in an anti-guide mode.
Claim 15
Dependent Claim 30 words
A semiconductor laser according to claim 12, wherein the multi-layered current and light confining portions further include another laser beam transmission layer formed adjacent to the laser beam absorption layer.
Claim 16
Dependent Claim 43 words
A semiconductor laser according to claim 12, wherein a refractive index in the laser beam transmission layer is smaller than the equivalent refractive index in the multi-layered current and light confining portions with respect to the laser beam in the fundamental transverse mode.
Claim 17
Dependent Claim 59 words
A semiconductor laser according to claim 13, wherein at least either one of the refractive index of the laser beam transmission layer or the equivalent refractive index of the another laser beam transmission layer is smaller than the equivalent refractive index in the multi-layered current and light confining portions with respect to the laser beam in the fundamental mode.
Claim 18
Dependent Claim 43 words
A semiconductor laser according to claim 12, wherein a band gap of the laser beam transmission layer is larger than that of the active layer, and a band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 19
Dependent Claim 43 words
A semiconductor laser according to claim 3, wherein a band gap of the laser beam transmission layer is larger than that of the active layer, and a band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 20
Dependent Claim 43 words
A semiconductor laser according to claim 14, wherein a band gap of the laser beam transmission layer is larger than that of the active layer, and a band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 21
Dependent Claim 52 words
A semiconductor laser according to claim 13, wherein any of the band gap of the laser beam transmission layer and the another laser beam transmission layer is larger than that of the active layer, and the band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 22
Dependent Claim 52 words
A semiconductor laser according to claim 15, wherein any of the band gap of the laser beam transmission layer and the another laser beam transmission layer is larger than that of the active layer, and the band gap of the laser beam absorption layer is smaller than that of the active layer.
Claim 23
Dependent Claim 43 words
A semiconductor laser according to claim 12, wherein a thickness of the laser beam absorption layer is equal to or less than 1/2 of a reciprocal of an absorption coefficient of the laser beam absorption layer with respect to a laser lasing wavelength.
Claim 24
Dependent Claim 34 words
A semiconductor laser according to claim 12, wherein the thickness of the laser beam absorption layer is equal to or less than a diffusion length of minority carriers in the laser beam absorption layer.
Claim 25
Dependent Claim 87 words
A semiconductor laser according to claim 12, wherein the multi-layered structure, the laser beam transmission layer, and the laser beam absorption layer are Al x Ga 1-x As layers; and wherein a mole fraction x of the laser beam transmission layer is set so that an optical confinement factor Γ of the active layer outside the stripe groove with respect to the laser beam in the guide mode is made larger than that outside the stripe groove with respect to the laser beam in the anti-guide mode.
Claim 26
Dependent Claim 93 words
A semiconductor laser according to claim 12, wherein the multi-layered structure, the laser beam transmission layer, and the laser beam absorption layer are (Al x Ga 1-x ) 0 .5 In 0 .5 P layers; and wherein a mole fraction x of the laser beam transmission layer is set so that an optical confinement factor Γ of the active layer outside the stripe groove with respect to the laser beam in the guide mode is made larger than that outside the stripe groove with respect to the laser beam in the anti-guide mode.

References Cited (Backward Citations)

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JPH01289185A Cited
JPH01289184A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-10-31 1998-05-02 1998-11-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-10-31 2002-05-02 2002-11-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-10-31 2006-05-02 2006-11-01 $7700.00 Window Closed / Lapsed

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