Generation of frequency-pre-selectable radiation by using more than one cascaded frequency conversion processes of resonantly enhanced beams

摘要

The invention describes methods and apparatus for the generation of laser radiation with pre-selectable frequency, which could be bigger or smaller than its fundamental beam frequency, through a combination of two or more intracavity frequency conversion processes of two or more resonantly enhanced beams. These techniques are particularly useful for generating continuous wave tunable frequency radiation in uv, visible and infrared wavelength ranges. These processes can be a combination of an intracavity fundamental beam pumped optical parametric oscillation (OPO) and an intracavity sum- or difference-frequency-mixing of the fundamental laser beam with an OPO generated beam and an intracavity frequency doubling the optical parametrical generated signal or idler beam to desirable frequencies for continuous wave. These plural intracavity nonlinear processes can be a combination of an intracavity or resonantly cavity-build-up fundamental beam pumped OPO and another frequency conversion within this OPO and the fundamental cavity. These intracavity enhanced frequency conversion processes allow for minimizing the parent frequency beams' losses and increasing the final conversion and, particularly, highly efficient conversion for continuous waves.