REPEATER, EXCITATION LIGHT SUPPLY DEVICE USED FOR THE SAME, AND EXCITATION LIGHT SUPPLY METHOD

• US 20150048238A1
• Filed: 02/07/2013
• Published: 02/19/2015
• Est. Priority Date: 02/14/2012
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Kawai, Motoyoshi
• Granted Patent: US 9,444,219 B2
• Time in Patent Office: Days
• US Class Current: 250/205
• CPC Class Codes: H01S 3/06754 Fibre amplifiers H01S3/06708 takes precedence
• CPC Class Codes: H01S 3/094061 Shared pump, i.e. pump light of a single pump source is used to pump plural gain media in parallel
• CPC Class Codes: H01S 3/09408 Pump redundancy
• CPC Class Codes: H01S 3/094096 Multi-wavelength pumping
• CPC Class Codes: H01S 3/09415 the pumping beam being parallel to the lasing mode of the pumped medium, e.g. end-pumping
• CPC Class Codes: H01S 3/2383 Parallel arrangements
• CPC Class Codes: H01S 5/0683 by monitoring the optical output parameters
• CPC Class Codes: H04B 10/291 in which processing or amplification is carried out without conversion of the main signal from optical form
• CPC Class Codes: H04B 13/02 Transmission systems in which the medium consists of the earth or a large mass of water thereon, e.g. earth telegraphy

Abstract

Even when some light emitting elements among the plurality of light emitting elements fail, a repeater, can be continuously operated. Means for solving the problems A light source unit 50 which includes a plurality of pumping light source modules 51 (51a to 51d) which include light emitting elements 52 (52a to 52d) for emitting an excitation light and monitor elements 53 (53a to 53d) for monitoring the excitation lights of the light emitting elements 52 (52a to 52d), respectively, a distribution unit 40 which combines the excitation lights from the plurality of pumping light source modules 51 (51a to 51d) and distributes it, and a control unit 60 which supplies a drive current flowing serially through the plurality of light emitting elements 52 (52a to 52d) in a plurality of excitation modules 51 (51a to 51d) are included.

Claims

1. An excitation light supply device which supplies an excitation light, comprising:

a light source unit which includes a plurality of excitation light source modules, each of which includes a light emitting element for emitting the excitation light and a monitor element for monitoring the excitation light of the light emitting element;

a distribution unit which combines the excitation lights from the plurality of excitation light source modules and distributes the combined excitation lights; and

a control unit which supplies a drive current flowing serially through the plurality of light emitting elements in a plurality of excitation modules.

2. The excitation light supply device according to claim 1, wherein

the control unit comprises:

a control circuit which detects an output signal of the monitor element, obtains a sum of the output signals as a monitor signal, generates a drive signal by which a level of the monitor signal is made equal to a reference value set in advance and outputs the drive signal; and

a drive circuit which outputs the drive current to the light source unit based on the drive signal.

3. The excitation light supply device according to claim 2, wherein

the control circuit monitors whether or not a no signal state in which a level of the output signal from the monitor element is zero exists and generates the drive signal based on the number of no signal states when the no signal state exists.

4. The excitation light supply device according to claim 1, wherein

one excitation light source module emits the excitation light having a predetermined wavelength and the wavelengths of the excitation lights emitted by the plurality of excitation light source modules are set so that the excitation lights having a plurality of wavelengths are supplied to the distribution unit.

5. A repeater, used for optical communication, comprising:

an optical amplifier provided to an optical fiber; and

an excitation light supply device described in claim 3 which supplies an excitation light to the optical amplifier.

6. An excitation light supply method for supplying an excitation light, comprising the steps of:

emitting the excitation light from a light emitting element and monitoring the excitation light by a monitor element at the time;

combining the emitted excitation lights and distributing it by a distribution unit;

detecting a sum of the detected output signals of the monitor elements as a monitor signal; and

outputting a drive current supplied to the plurality of light emitting elements connected in series based on the monitor signal.

7. The excitation light supply method according to claim 6, further comprising the steps of;

monitoring whether or not a no signal state in which a level of the detected output signal of the monitor element is zero exists;

wherein

the drive current is outputted based on the number of no signal states and the monitor signal.

8. The excitation light supply method according to claim 7, wherein

the light emitting elements emit the excitation lights having different wavelengths from each other.