Single Frequency Laser with Intracavity Electro-Optic Phase Modulation for Frequency Agility and Frequency Stabilization

Single frequency lasers with rapid tuning ability and subsequent active phase noise suppression for sub-1kHz linewidths are key components for coherent laser applications requiring long coherence length local oscillators and Doppler frequency shift compensation. Such applications include airborne and space-borne long-range micro-Doppler imaging and inter-satellite coherent communications. Coherent Technologies, Inc. proposes to develop a compact laser source based on Nd:YVO4 operating at 1.064 microns, that uses intracavity electro-optic phase modulation to both provide sub-1ms step frequency-tuning over a 60GHz range and sub-1kHz long term frequency stability achieved within a few hundred microseconds timescale. Frequency stability is achieved using a wide bandwidth servo locking scheme. In Phase 1, CTI will determine means for compacting the frequency-agile and frequency-stable laser design for practical deployment on ground, airborne and space-based platforms, and will address means for decreasing the characteristic timescale for frequency tuning and frequency settling to a few hundred microseconds. In Phase 2, CTI will develop a frequency-agile and frequency stable laser source meeting these tuning requirements with an average single frequency output power of 100mW over the 60GHz tuning range. The compact laser architecture will also facilitate commercialization of the frequency-agile and frequency-stable laser technology for Optical Air Data sensing applications.