WAVELENGTH-TUNABLE LIGHT SOURCE AND WAVELENGTH CONTROL METHOD THEREOF

• Main Authors: KAMISAKA KATSUMI, MIURA TOMOKO
• Format: Patent
• Language: English; Japanese
• Published: 08.10.2020
• Subjects: BASIC ELECTRIC ELEMENTS; DEVICES USING STIMULATED EMISSION; ELECTRICITY

To provide a wavelength-tunable light source and a wavelength control method thereof that can shorten a time until a wavelength-tunable laser stabilizes at a target oscillation frequency even when a thermoelectron cooler is shared between a frequency rocker and the wavelength-tunable laser.SOLUTION: A wavelength-tunable light source includes a wavelength-tunable laser having an SG-DFB region including a first heater and a CSG-DBR region including a second heater and photocoupled to the SG-DFB region, a frequency rocker that receives the output light of the wavelength-tunable laser and outputs two electrical control signals that have periodicity with respect to the frequency of the output light and are 90° out of phase with each other, a thermoelectron cooler equipped with the wavelength-tunable laser and the frequency rocker, and a controller that controls the temperature of the first heater, the second heater, and the thermoelectron cooler on the basis of one of the two control signals.SELECTED DRAWING: Figure 1 【課題】周波数ロッカと波長可変レーザとで熱電子冷却器を共通化した態様であっても、波長可変レーザが目標発振周波数で安定化するまでの時間を短縮可能な波長可変光源及びその波長制御方法を提供する。【解決手段】 波長可変光源は、第１のヒータを含むＳＧ−ＤＦＢ領域、及び、第２のヒータを含むと共にＳＧ−ＤＦＢ領域に光結合するＣＳＧ−ＤＢＲ領域を有する波長可変レーザと、波長可変レーザの出力光を受け、当該出力光の周波数に対して周期性を有すると共に互いに位相が９０°異なる電気的な二つの制御信号を出力する周波数ロッカと、波長可変レーザ及び周波数ロッカを搭載する熱電子冷却器と、二つの制御信号の何れか一方に基づいて、第１のヒータ、第２のヒータ、及び、熱電子冷却器の温度を制御するコントローラと、を備える。【選択図】図１