EP0283248A2
Expired / Lapsed
EP
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Laser devices
Assignee: Toshiba Corp
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Filing: 1988-03-15
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Granted: —
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Expires: 2008-03-15
Abstract
Abstract A laser device has a semiconductor laser (61) which has at least two longitudinal modes λ₀ and λ₁ both of which are able to oscillate, and oscillating at the single longitudinal mode λ₀. The device further comprises input means(62) which inputs a wave nearly coincident with λ₁ to the semiconductor laser (61) maintains its oscillating wavelength λ₁ even if the intensity of said wave input from said input means (62) reduces.
Inventors
- 👤 Hiroyuki C/O Patent Division Ibe
- 👤 Hideaki C/O Patent Division Yamakawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 16:57
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/40; H01S5/4006; H01S5/10; H01S5/12
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
108 words
A laser device, comprising: a semiconductor laser (61, 71,81), said semiconductor laser having at least two longitudinal modes with wavelengths λ₀ and λ₁ at which it is able to oscillate, and means for oscillating said semiconductor laser at the single longitudinal mode λ₀; and input means (62,63;72,73,74;82,83,84) for inputting a wave of a wavelength which nearly coincides with said wavelength λ₁ of said semiconductor laser (61,71,81) to switch the oscillating wavelength of said semiconductor laser from λ₀ to λ₁, such that said semiconductor laser (61,71,81) maintains its oscillating at the single longitudinal mode of λ₁ even if the intensity of said wave input from said input means reduces.
Claim 2
Dependent Claim
108 words
A laser device, comprising: a semiconductor laser (61, 71,81), said semiconductor laser having at least two longitudinal modes with wavelengths λ₀ and λ₁ at which it is able to oscillate, and means for oscillating said semiconductor laser at the single longitudinal mode λ₀; and input means (62,63;72,73,74;82,83,84) for inputting a wave of a wavelength which nearly coincides with said wavelength λ₁ of said semiconductor laser (61,71,81) to switch the oscillating wavelength of said semiconductor laser from λ₀ to λ₁, such that said semiconductor laser (61,71,81) maintains its oscillating at the single longitudinal mode of λ₁ even if the intensity of said wave input from said input means reduces.
Claim 3
Dependent Claim
37 words
A laser device according to claim 1, including means for returning said semiconductor laser to its oscillating wavelength λ₀ for said wavelength λ₁ by inputting a wave with a wavelength which nearly coincides with said wavelength λ₀.
Claim 4
Dependent Claim
32 words
A laser device according to claim 1, including means from returning said semiconductor laser to its oscillating wavelength λ₀ from said wavelength λ1 by reducing a drive current of said semiconductor laser.
Claim 5
Dependent Claim
29 words
A laser device according to claim 1 wherein said semiconductor laser maintain its oscillating wavelength λ₁ after reducing the intensity of input wave from said input means to zero.
Claim 6
Dependent Claim
48 words
A laser device according to claim 1, wherein said input means is an optical switch means having a wave input section for receiving a first wave and a second wave and a clock input section for selecting an output wavelength from said first wave and said second wave.
Claim 7
Dependent Claim
53 words
A laser device according to claim 1, wherein said input means comprises a first wave source for producing a first wave, a second wave source and a connecting means to connect said first and second wave sources to said semiconductor laser, wherein one of said waves is selectively input to said semiconductor laser.
Claim 8
Dependent Claim
15 words
A laser device according to claim 6, wherein said connecting means is a beam splitter.
Claim 9
Dependent Claim
16 words
A laser device according to claim 6, wherein said connecting means is an optical wave guide.
Claim 10
Dependent Claim
15 words
A laser device according to claim 1, wherein said input means is a laser source.
Claim 11
Dependent Claim
21 words
A laser device according to claim 1, wherein said longitudinal modes are the nearest two longitudinal modes of said semiconductor laser.
Claim 12
Dependent Claim
26 words
A laser device according to claim 1, wherein one of said longitudinal modes is at the Bragg wavelength, and the other one is a sub mode.
Claim 13
Dependent Claim
23 words
A laser device according to claim 1, wherein said semiconductor laser has an active layer and a grating means along the active layer.
Claim 14
Dependent Claim
14 words
A laser device according to claim 1, wherein said semiconductor laser is λ/4 shifted.
Claim 15
Dependent Claim
18 words
A laser device according to claim 1, wherein drive current of said laser is above the threshold value.
Claim 16
Dependent Claim
33 words
A laser device according to claim 1, wherein said semiconductor laser has a drive current and a threshold value, said drive current of said laser being 1.4 times higher than the threshold value.
Claim 17
Dependent Claim
27 words
A laser device according to claim 1, further comprising: optical isolator means to selectively allow the wave to transfer from said input means to said semiconductor laser.
Claim 18
Dependent Claim
18 words
A laser device according to claim 1, wherein the transverse mode of said semiconductor lasers are the same.
Claim 19
Dependent Claim
31 words
A laser device according to claim 1, wherein the mode of said input wave and the modes of the output waves λ₀, λ₁ of said semiconductor laser are transverse electric modes.
References Cited (Backward Citations)
No citation records indexed.
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