EXTERNAL CAVITY TUNABLE LASER AND CAVITY MODE LOCKING METHOD THEREOF

摘要

An external cavity tunable laser and a cavity mode locking method thereof. The external cavity tunable laser comprises a semiconductor optical amplifier (1) used for providing gains. Two end surfaces of the semiconductor optical amplifier (1) are partly plated with a reflecting film and an antireflection film separately. A beam expansion collimation lens (2), a tunable filter (3), a fixed grid filter (4) and an external cavity reflector (6) are disposed on one side, plated with the antireflection film, of the semiconductor optical amplifier (1) so as to form an external cavity of the external cavity tunable laser. The external cavity of the external cavity tunable laser further comprises a large-phase adjustment assembly (5) and a phase fast-adjustment assembly (7). The large-phase adjustment assembly (5) can adjust the cavity length of the external cavity of the external cavity tunable laser in a large range. The phase fast-adjustment assembly (7) can fast adjust the cavity length of the external cavity of the external cavity tunable laser. The apparatus and the method are used for achieving wavelength locking, the structure is simple, and the accuracy of wavelength locking is high.