| 摘要 |
This application is concerned with the generation of an optical comb signal using an externally seeded gain-switched multi-modal laser diode 2, such as a Fabry-Perot laser. An RF signal input through a bias-tee provides the gain switching, the frequency of which determines the comb spacing. The external seeding is provided by a tunable single mode laser 4 which provides injection seeding into the lasing cavity of the multi-modal laser. Preferably the seeding is input through a circulator, CIR. The wavelength of the single mode laser determines the centre frequency of the comb (Fig. 6). Fine tuning may be provided through temperature adjustment of the multi-modal device. In one embodiment external phase modulation (PM) is used to extend the width of the comb signal. |
