Title:
OPTICAL PHASE SYNCHRONIZATION LIGHT SOURCE AND OPTICAL FREQUENCY SYNCHRONIZATION LIGHT SOURCE
Document Type and Number:
Japanese Patent JP3411832
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To realize highly reliable optical phase synchronization and optical frequency synchronization by controlling a resonator length of optical frequency variable laser light source, a refractive index of a laser resonator and the temperature of a laser resonator based on a low frequency element of an error signal.
SOLUTION: An optical multiplexer 41 combines controlled light and reference signal light. When a signal showing optical frequency difference of both lights is output from a balanced receiver 42, a phase detection means 6 inputs an output signal of a balanced receiver 42 and an output signal of an offset frequency setting means 5 for detecting phase error of both lights. That is, only a low frequency element of an error signal which is fed back to an optical frequency variable laser light source 1 is separated and a resonator length of the optical frequency variable laser light source 1 is controlled. Thereby, loop gain of a DC proximate element can be increased and an optical phase synchronization holding width can be increased to GHz or more without greatly affecting output light intensity of the optical frequency variable laser light source 1.
Inventors:
Koh Imajuku
Atsushi Takada
Atsushi Takada
Application Number:
JP23276098A
Publication Date:
June 03, 2003
Filing Date:
August 19, 1998
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
H01S3/139; H01S3/10; H01S5/00; H01S5/0687; H04B10/07; H04B10/293; H04B10/516; H04B10/564; H04B10/572; H04B10/61; (IPC1-7): H01S5/0687; H01S3/10; H04B10/04; H04B10/06; H04B10/14
Domestic Patent References:
| JP7249232A | ||||
| JP669580A | ||||
| JP7264136A |
Attorney, Agent or Firm:
Furuya Fumio