Patent EP0377948A2 successfully refreshed from Google Patents.
EP0377948A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
An optical amplifying device
Assignee: Toshiba Corp
•
Filing: 1989-11-03
•
Granted: —
•
Expires: 2009-11-03
Abstract
Abstract A device for amplifying an input optical signal includes an optical amplifier having a gain control region (14) in which the input optical signal is amplified, a first detecting region (13) for detecting the input optical signal, and a second detecting region (15) for detecting an amplified optical signal. The gain of the optical amplifier is controlled by a gain control signal from a signal source (17). A controller (18), responsive to detecting signals (S1,S2) from the first and second detecting regions (13,15), produces a source control signal which is supplied to control the signal source (17).
Inventors
- 👤 Hideaki Intellectual Property Division Yamakawa
- 👤 Nobuo Intellectual Property Division Suzuki
- 👤 Takeshi Intellectual Property Division Ozeki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 16:34
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/29; H01; H01S; H01S5/00; H01S5/50; H01S5/0014; H01S5/0028; H01S5/02; H01S5/026; H01S5/0262; H01S5/0264
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
120 words
A device for amplifying an input optical signal characterized by: optical amplifying means (A) having a gain control section (14) for amplifying the input optical signal to produce an amplified optical signal in accordance with a gain control signal; a first detecting section (13) for detecting the input optical signal; and a second detecting section (15) for detecting the amplified optical signal from the gain control section (14); control means (18, 51, 52, 81) responsive to detected signals from the first and second detecting sections (13, 14) for producing a source control signal related thereto; and signal source means (17, 53, 82), coupled to the amplifying means (A), for generating a gain control signal corresponding to the source control signal.
Claim 2
Independent Claim
120 words
A device for amplifying an input optical signal characterized by: optical amplifying means (A) having a gain control section (14) for amplifying the input optical signal to produce an amplified optical signal in accordance with a gain control signal; a first detecting section (13) for detecting the input optical signal; and a second detecting section (15) for detecting the amplified optical signal from the gain control section (14); control means (18, 51, 52, 81) responsive to detected signals from the first and second detecting sections (13, 14) for producing a source control signal related thereto; and signal source means (17, 53, 82), coupled to the amplifying means (A), for generating a gain control signal corresponding to the source control signal.
Claim 3
Dependent Claim
27 words
The device of claim 1, characterized in that the optical amplifying means (A) includes means (131, 141, 151) for restricting a reflection factor of the optical signals.
Claim 4
Dependent Claim
59 words
The device of claim 1 or claim 2 further characterized in that the first detecting portion (13) of the optical amplifying means (A) includes means for generating a first electrical signal (S1) corresponding to the input optical signal and the second detecting portion (15) includes means for generating a second electrical signal (S2) corresponding to the amplified optical signal.
Claim 5
Independent Claim
74 words
A device according to any preceding claim further characterized in that the control means (18) includes: divider means (181) for generating a signal corresponding to the ratio of levels of the input optical signal and the amplified optical signal as detected by the first and second detecting sections (13, 15), respectively; and differential amplifier means (182) for producing the source control signal in accordance with the difference between the ratio and a reference value.
Claim 6
Dependent Claim
59 words
A device according to claim 3, characterized in that the control means (18) includes: divider means (181) for generating a ratio signal corresponding to a ratio of levels of the first and second electrical signals (S1, S2); and differential amplifier means (182) for producing the source control signal corresponding to the difference between the ratio and a reference value.
Claim 7
Independent Claim
37 words
A device according to any preceding claim, further characterized in that the signal source means (17) includes a transistor (31) for producing a gain control current, corresponding to the source control signal, as the gain control signal.
Claim 8
Dependent Claim
47 words
A device according to claim 1, characterized in that the control means (18, 81) includes means (181, 182, 811, 812, 813) for controlling the gain control signal from the signal source means so that the gain of the optical amplifying means is maintained at a constant value.
Claim 9
Dependent Claim
31 words
A device according to claim 1, further characterized in that the signal source means (17) includes means (41) for producing the gain control signal substantially equal to the source control signal.
Claim 10
Dependent Claim
63 words
A device according to claim 8, further characterized in that the signal source means (17) includes two transistors (42, 43) in a common-base and common-emitter configuration, one of the transistors having the source control signal applied to its collector and having the base and collector connected together and the gain control signal being produced at the collector of the other of the transistors.
Claim 11
Dependent Claim
41 words
A device according to claim 1, further characterized in that the control means (51, 52) includes means for controlling the gain control signal from the signal source means (53) so that the amplified optical signal is maintained at a constant value.
Claim 12
Dependent Claim
47 words
A device according to claim 10, characterized in that the controlling means (51, 52) includes a differential amplifier (51) for producing the source control signal corresponding to the difference between a level of the detected signal from the first detecting portion (13) and a first reference level.
Claim 13
Dependent Claim
47 words
A device according to claim 10, characterized in that the control means (51, 52) includes a differential amplifier (52) for producing the source control signal corresponding to the difference between a level of the detected signal from the second detecting portion (15) and a second reference level.
Claim 14
Dependent Claim
91 words
A device according to claim 1, further characterized in that the controlling means (51, 52) includes means (51, 52) for producing a first source control signal corresponding to the difference between a level of the detected signal from the first detecting portion (13) and a first reference level, and for producing a second source control signal corresponding to the difference between a level of the detected signal from the second detecting portion (15) and a second reference level, the first and second source control signals controlling the signal source means (53).
Claim 15
Dependent Claim
74 words
A device according to claim 13, characterized in that the signal source means (53) includes: a first transistor (61) having a base provided with the first source control signal; and a second transistor (62) having a base being provided with the second source control signal, an emitter being connected to a collector of the first transistor (61), and a collector being connected to th gain control portion (14) of the optical amplifying means (A).
Claim 16
Dependent Claim
41 words
A device according to claim 13, characterised in that the signal source means (53) includes means (63, 64, 65) for producing the gain control signal substantially equal to the difference between the levels of the first and second source control signals.
Claim 17
Dependent Claim
64 words
A device according to claim 13, characterised in that the signal source means (53) includes means (61, 62, 63, 64, 72, 73, 74, 75) for producing a first gain control signal corresponding to the first source control signal, and a second gain control signal corresponding to the second source control signal, the first and second gain control signals controlling the optical amplifying means (A).
Claim 18
Dependent Claim
80 words
A device according to claim 1, characterized in that the control means (81) includes: a divider (811) for generating a signal corresponding to a ratio of levels of the input optical signal and the amplified optical signal; processing means (813) for producing a predetermined level corresponding to characteristics of the optical amplifying means (A); and a differential amplifier (812) for producing the source control signal corresponding to the difference between a level of the ratio signal and the predetermined level.
Claim 19
Dependent Claim
43 words
A device according to claim 1, characterised in that the optical amplifying means (A) includes a semiconductor laser amplifier having a gain control section (14) and first and second detecting sections (13, 15), each section being separated from the others by space (20).
Claim 20
Dependent Claim
28 words
A device according to claim 18, characterized in that the semiconductor laser amplifier has dielectric multilayers (131, 141, 151) formed on faces of the sections (13, 14, 15).
Claim 21
Dependent Claim
33 words
A device according to claim 1, characterized in that the first detecting section (13) comprises an optical coupler (13C, 15C) having optical fibers (132, 134) for diving the input optical signal into portions.
Claim 22
Dependent Claim
32 words
A device according to claim 1, characterized in that the second detecting section (14) comprises an optical coupler (15C) having optical fibers (152, 154) for dividing the amplified optical signal into portions.
Claim 23
Dependent Claim
59 words
A device according to claim 1, characterized in that the optical amplifying means (A) includes a semiconductor laser amplifier having an active layer (16) provided with the input optical signal, a first branch (161) of the active layer (16) dividing the input optical signal, and a second branch (162) of the active layer (16) dividing the amplified optical signal.
Claim 24
Dependent Claim
67 words
A device according to claim 1, characterized in that the optical amplifying means (A) comprises a semiconductor laser amplifier including cladding layers (11, 12) and an active layer (16) between the cladding layers (11, 12), one of the cladding layers (11, 12) having grooves (121, 122) between each detecting section (13, 15) and the gain control section (14) for cutting off currents in the cladding layer (12).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.