Patent EP0282331A2 successfully refreshed from Google Patents.
EP0282331A2
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Distributed feedback semiconductor laser with monitor
Assignee: KDDI Corp
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Filing: 1988-03-11
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Granted: —
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Expires: 2008-03-11
Abstract
Abstract A distributed feedback semiconductor laser with monitor, in which the energy gap of a light absorbing layer (16,(17)) provided on the window region (31) alone is smaller than the energy gap of the light emitting layer (3) and in which an independent pn-junction isolated from the pn-junction in the laser region is provided in or at one edge of the light absorbing layer (16, (17)) on the window region (31).
Inventors
- 👤 Masashi Usami
- 👤 Shigeyuki Akiba
- 👤 Katsuyuki Utaka
- 👤 Yuichi Matsushima
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 21:55
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02; H01S5/026; H01S5/0262; H01S5/0264; H01S5/10; H01S5/12; H01S5/16; H01S5/164
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
156 words
A distributed feedback semiconductor laser with monitor, comprising: a laser region (30) having a light emitting layer (3), an effective periodic refractive index variation (10) along the direction of travel of light and a pn-junction provided in the vicinity of the light emitting layer; a window region (31) formed by burying in at least one end of the light emitting layer a semiconductor layer (5,6) of a larger energy gap than that of the light emitting layer; and a light absorbing layer (16,17) formed on the window region; wherein the energy gap of the light absorbing layer (16) is set to a value smaller than that of the light emitting layer, and a pn-junction isolated from the pn-junction in the laser region is provided in the light absorbing layer (16) on the window region so that a part of a light output from the light emitting layer is monitored through the pn-junction in the window region.
Claim 2
Dependent Claim
156 words
A distributed feedback semiconductor laser with monitor, comprising: a laser region (30) having a light emitting layer (3), an effective periodic refractive index variation (10) along the direction of travel of light and a pn-junction provided in the vicinity of the light emitting layer; a window region (31) formed by burying in at least one end of the light emitting layer a semiconductor layer (5,6) of a larger energy gap than that of the light emitting layer; and a light absorbing layer (16,17) formed on the window region; wherein the energy gap of the light absorbing layer (16) is set to a value smaller than that of the light emitting layer, and a pn-junction isolated from the pn-junction in the laser region is provided in the light absorbing layer (16) on the window region so that a part of a light output from the light emitting layer is monitored through the pn-junction in the window region.
Claim 3
Dependent Claim
161 words
A distributed feedback semiconductor laser with monitor, comprising: a laser region (30) having a light emitting layer (3), an effective periodic refractive index variation (10) along the direction of travel of light and a pn-junction provided in the vicinity of the light emitting layer; a window region (31) formed by burying in at least one end of the light emitting layer a semiconductor layer (5,6) of a larger energy gap than that of the light emitting layer; and a light absorbing layer (16) formed on the window region; wherein the energy gap of the light absorbing layer (16) is set to a value smaller than that of the light emitting layer, and a pn-junction isolated from the pn-junction in the laser region (30) is provided at one edge of the light absorbing layer (16) on the window region so that a part of a light output from the light emitting layer is monitored through the pn-junction in the window region (31).
Claim 4
Dependent Claim
161 words
A distributed feedback semiconductor laser with monitor, comprising: a laser region (30) having a light emitting layer (3), an effective periodic refractive index variation (10) along the direction of travel of light and a pn-junction provided in the vicinity of the light emitting layer; a window region (31) formed by burying in at least one end of the light emitting layer a semiconductor layer (5,6) of a larger energy gap than that of the light emitting layer; and a light absorbing layer (16) formed on the window region; wherein the energy gap of the light absorbing layer (16) is set to a value smaller than that of the light emitting layer, and a pn-junction isolated from the pn-junction in the laser region (30) is provided at one edge of the light absorbing layer (16) on the window region so that a part of a light output from the light emitting layer is monitored through the pn-junction in the window region (31).
Claim 5
Dependent Claim
45 words
A distributed feedback semiconductor laser with monitor according to any preceding claim, further comprising an anti-reflection coating film (19) provided at one end of the laser region (30) to pass therethrough the main part of the light output (102,104) from the light emitting layer (3).
Claim 6
Dependent Claim
41 words
A distributed feedback semiconductor laser with monitor according to any preceding claim, in which the light absorbing layer (16) is formed on a p-type layer (15) having a value of energy gap larger than that of the light emitting layer (3).
References Cited (Backward Citations)
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