Broadly and fast tunable optical parametric oscillator

摘要

A coherent light source is provided for producing narrow-linewidth output, continuously tunable within a broad (at least one-octave-wide) range of optical wavelengths. The source is based on type-I or type-0 near-degenerate optical parametric oscillator (OPO), which uses a nonlinear optical crystal with either birefringent phase matching or quasi phase matching. The pump wavelength is chosen such that the OPO degeneracy wavelength (at twice the pump wavelength), is close to the point of zero group-velocity dispersion. That results in an extremely broad OPO bandwidth. Fast OPO wavelength tuning is achieved by rotating an intracavity diffraction grating. In accordance with the invention, the choice of a nonlinear crystal and a pump source determines the overall tuning range. For example, the use of lithium niobate provides tuning over the range of 1.3 to 3 microns, ZGP—3.8 to 8 microns, gallium arsenide—4 to 12 microns, CGA—6 to 13 microns.

主权项

1. A laser system for producing a narrow-bandwidth, coherent, infrared radiation, wavelength tunable output beam, comprising:
a pump wavelength source providing a selected pump wavelength output; an optical parametric oscillator (OPO) including a nonlinear optical component, disposed to receive the selected pump wavelength output; and an output controllable, spectrally selective element disposed within the OPO,further characterized by a tuning rate that is equal to or greater than 1 kHz for any two wavelengths over a gain bandwidth.