US Patent 7283573 Optical microwave source

A simple, tuned monolithic integrated component for the generation of optical microwaves in the frequency range of from 0.5 GHz to the THz range by means of an optical microwave source, embodied as a multi-section semiconductor laser, the sections of which are such as to be independently electrically controlled, with a single mode DFB laser, driven above the laser threshold and at least one monolithic integrated (external) cavity, having a passive phase control section and an active section.