| 摘要 |
PURPOSE:To stabilize the oscillation frequency of LD and obtain a light source for wavelength multiplex optical communication with high order multiplexing level by forming an external optical resonator of a particular wavelength to each LD, detecting variation of power of 0th order diffracted light at the flat diffraction lattice and effectuating a negative feedback to the drive circuit of LD. CONSTITUTION:A resonance frequency is varied and the oscillation frequency of LD1 is also varied within the range of gain by changing the position in the plane (x'-y') of reflector 6 at the focal point surface of lens 5. Therefore, if the LD light source which oscillates with a constant wavelength interval is required as the light source for wavelength multiplex optical communication, a plurality of reflectors 6 are arranged at the necessary wavelength positions and moreover the emitting end of optical fiber is scattered for arrangement in the direction of y axis. Thus, while the diffracted light of LD1 is focused through scattering in the direction of y' axis on the focal point surface of condenser lens 5 and overlaps the skirts of spectrum generated by spreading of gain of LD1 is avoided on the focal point surface of lens, 5 the reflectors 6 are bidimensionally arranged on the x'-y' plane to form an external light resonator. |
