OPTICAL TRANSMITTER EMITTING LIGHT WITH NARROWED LINEWIDTH

摘要

An optical transmitter that narrows the linewidth of the output light is disclosed. The optical transmitter includes a wavelength tunable laser diode (LD) type of the CSG-DR LD integrated with a semiconductor optical amplifier (SOA) driven by the constant magnitude mode. The wavelength of the light output from the LD is determined through the etalon filter. The optical transmitter feeds the output of the etalon filter back to the injection current supplied to the LID to reduce the phase noise inherently contained in the output light.

主权项

1. An optical transmitter, comprising:
a wavelength tunable laser diode (t-LD) that emits light at a target wavelength, the t-LD providing a sampled grating distributed feedback (SG-DFB) section and a chirped sampled grating distributed Bargg reflector (CSG-DBR) section that forms an optical cavity combined with the SG-DFB section, the optical cavity setting an emission wavelength of the t-LD at the target wavelength; an optical component having a wavelength dependent transmittance, the optical component receiving the light emitted from the t-LD; and an optical detector that receives an output of the optical component, wherein the output of the optical detector is superposed on a bias current supplied to the SG-DFB section of the t-LD.