Title:
FREQUENCY MODULATION SYSTEM
Document Type and Number:
Japanese Patent JP3451890
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a new broadband frequency modulation system which is not affected by a residual AM component of a laser and has excellent FM modulation characteristics.
SOLUTION: A 1st modulated signal and a 2nd modulated signal which are opposite in phase from each other are generated form a modulated signal to modulate the current flowing to a 1st semiconductor laser 1 with the 1st modulated signal and the current flowing to a 2nd semiconductor laser 2 with the 2nd modulated signal, and the output light of the 1st semiconductor laser and the output light of the 2nd semiconductor laser are put together by an optical coupler 5. Remaining AM modulation components are opposite in phase from each other, so they cancel each other.
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Inventors:
Masahiko Kobayashi
Application Number:
JP15484397A
Publication Date:
September 29, 2003
Filing Date:
June 12, 1997
Export Citation:
Assignee:
Hitachi Cable Ltd.
International Classes:
G02F2/02; H01S5/06; H04B10/00; H04B10/07; H04B10/516; H04B10/548; H04B10/564; H04B10/61; (IPC1-7): G02F2/02; H04B10/00; H04B10/04; H04B10/06; H04B10/142; H04B10/152
Domestic Patent References:
| JP9312624A | ||||
| JP10190586A |
Attorney, Agent or Firm:
Nobuo Kinutani
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