Abstract: A system for providing a single pulse of laser oscillator radiation of broad spectral range operative to excite a plurality of modes of a ring laser operating as an injection locked oscillator. In order to provide injection locking of the ring oscillator at multiple modes, a pump laser for the laser oscillator has its cavity length substantially similar to that of the laser oscillator thereby producing partial mode locking of the laser oscillator by amplitude modulation of the pump laser. In this manner the laser oscillator provides a single pulse of mode rich frequencies which are chosen within the band desired in the ring laser. This pulse continuously circulates within the cavity of the laser oscillator. The output of the laser oscillator through an output mirror thus forms a series of pulses separated in time by the roundtrip delay of the laser oscillator cavity. A single such pulse is selected by Pockels cell gating for injection into the ring oscillator.

Abstract: A system for making optimum use of frequency shifted radiation by extracting both front and back travelling frequency shifted radiation beams. The two extracted laser beams are later combined in the same polarization for energization of a dye laser channel or cell for increased pumping efficiency in the dye laser operation. Additionally, where the generating cavity for the two beams is mode locked, the two extracted beams may be applied to the dye laser cell in time staggered manner in order to maintain the stability of subsequent amplification stages between pulses.