| 摘要 |
PURPOSE:To realize simultaneous stabilization of the frequency interval of arbitrary number of lasers by converting the oscillation frequency interval of a plurality of lasers to the time interval and by controlling the error signal, which is obtained by comparing the time interval with a time interval corresponding to the frequency interval standard, to have a definite value. CONSTITUTION:Pulsed electric signal is output from a low-pass filter when the difference between the beam frequency from 1.55mum band phase control region distribution reflection type laser DFB-LD1 and the beam frequency from 1.55mum distribution feedback type lasers DFB-LD 4, 5, 6 is within the range of about 100MHz. The number of pulse is three and is the same as that of the oscillation frequency difference which comes in the range of 100MHz in one cycle of the output signal of a sawtooth generator 2. The output of the third photo detector 21 through the low-pass filter is applied to the third input terminal 33 of a controller 3. In the controller 3, the error signal is the time difference of pulse generation between the input to the first input terminal 31 and the input to the third input terminal 33, and a control signal is output to control the difference to be of a definite value. The control signal from the controller 3 is input to laser driving equipment 22, 23 and 24. |
