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US5224112A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor laser device driving circuit

Assignee: Sumitomo Electric Industries Ltd
•
Filing: 1992-01-27
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Granted: 1993-06-29
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Expires: 2012-01-27
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Abstract

Abstract A semiconductor laser device driving circuit including a semiconductor laser device, a detection unit for detecting a luminous output of the semiconductor laser device, a reference current unit for providing reference currents for reference maximum and minimum values of the luminous output of the semiconductor laser device, and a driving unit for supplying currents to the semiconductor laser device so as to make maximum and minimum values of the luminous output of the semiconductor laser device detected by the detection unit coincident with the reference maximum and minimum values determined by the reference currents. In the semiconductor laser device driving circuit, the reference currents are given as differences between a plurality of currents supplied from current sources.

Inventors

  • 👤 Katsumi Uesaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 09:17
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/06; H01S5/068; H01S5/0683; H01S5/06832

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 130 words
A semiconductor laser device driving circuit comprising: a semiconductor laser device; detection means for detecting a luminous output of said semiconductor laser device and generating detected current signals corresponding to detected minimum and maximum luminous output values of said semiconductor laser device; current source means for generating a plurality of source current signals; reference current means for generating a plurality of reference current signals corresponding to reference maximum and minimum luminous output values of said semiconductor laser device, said plurality of reference current signals being differences between the plurality of said source current signals supplied from said current source means; and driving means for receiving said detected current signals and said reference current signals, generating corresponding driving current signals and supplying said driving current signals to said semiconductor laser device.
Claim 2
Dependent Claim 130 words
A semiconductor laser device driving circuit comprising: a semiconductor laser device; detection means for detecting a luminous output of said semiconductor laser device and generating detected current signals corresponding to detected minimum and maximum luminous output values of said semiconductor laser device; current source means for generating a plurality of source current signals; reference current means for generating a plurality of reference current signals corresponding to reference maximum and minimum luminous output values of said semiconductor laser device, said plurality of reference current signals being differences between the plurality of said source current signals supplied from said current source means; and driving means for receiving said detected current signals and said reference current signals, generating corresponding driving current signals and supplying said driving current signals to said semiconductor laser device.
Claim 3
Dependent Claim 101 words
The semiconductor laser device driving circuit according to claim 1, wherein said current source means includes first, second and third current sources, a first reference current signal of the plurality of reference current signals being a difference between a first source current signal supplied from said first current source and a second source current signal supplied from said second current source, and a second reference current signal of the plurality of reference current signals being a difference between said first source current signal supplied from said first current source and a third source current signal supplied from said third current source.
Claim 4
Dependent Claim 64 words
The semiconductor laser device driving circuit according to claim 1, wherein said driving means includes a first differential amplifier supplied with said detected maximum luminous output value and said reference maximum luminous output value of said semiconductor laser device, and a second differential amplifier supplied with said detected minimum luminous output value and said reference minimum luminous output value of said semiconductor laser device.
Claim 5
Dependent Claim 44 words
The semiconductor laser device driving circuit according to claim 3, further comprising control means for controlling a pulse width of a modulation current for said semiconductor laser device modulated by an input signal which is based on an output of said second differential amplifier.
Claim 6
Dependent Claim 65 words
The semiconductor laser device driving circuit according to claim 1, wherein said driving means supplies a modulation current to said semiconductor laser device based on said detected and said reference maximum luminous output values of said semiconductor laser device, and supplies a bias current to said semiconductor laser device based on said detected and said reference minimum luminous output values of said semiconductor laser device.
Claim 7
Dependent Claim 17 words
The semiconductor laser device driving circuit according to claim 1, wherein said detection means includes a photodiode.
Claim 8
Dependent Claim 51 words
The semiconductor laser device driving circuit according to claim 1, further comprising control means for controlling a pulse width of a modulation current for said semiconductor laser device modulated by an input signal which is based on said detected and said reference minimum luminous output values of said semiconductor laser device.

References Cited (Backward Citations)

DE3404444A1 Cited
JPS6025335A Cited
JPS6142182A Cited
CA1229653A Cited
JPS61283237A Cited
DE4030995A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-06-28 1996-12-28 1997-06-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-06-28 2000-12-28 2001-06-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-06-28 2004-12-28 2005-06-29 $7700.00 Window Closed / Lapsed

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