Apparatus and methods for using achromatic phase matching at high orders of dispersion

An instantaneously tunable optical parametric generator, comprising:

• a nonlinear optical medium having:
• a negative birefringence;
• first and second parallel plane faces, said second plane face having a zero-order half-wave plate fixedly attached thereto, said half-wave plate for rotating a light beam polarization from a first polarization type to a second polarization type;
• an optimum entrance angle for every wavelength of light, said optimum entrance angle varying as a high order polynomial function of said light wavelength;
• and
• an optical pumping beam, said optical pumping beam being a narrow-band coherent light beam having a pumping beam frequency and a corresponding pumping beam wavelength, said optical pumping beam entering said nonlinear optical medium first plane face at an angle matching said optimum entrance angle for said pumping beam wavelength to at least a second order approximation of said high order polynomial function, said optical pumping beam interacting with said nonlinear optical medium to provide converted signal and idler beams having broadened bandwidths, wherein each of said converted signal and idler beams comprises a plurality of output rays having frequencies less than said pumping beam frequency and corresponding wavelengths greater than said pumping beam wavelength;
• and
• optical means for reconstructing said converted signal beam into a collinear beam, wherein said signal beam output rays are all aligned about parallel to one another, said optical means collecting said converted signal beam output rays, de-magnifying a dispersion of said converted signal beam output rays, and spatially converging said converted signal beam output rays to form said collinear beam, wherein said collinear beam has a bandwidth of about 40 nm.

An optical parametric oscillator, comprising:

• an optical resonator cavity comprising:
• a nonlinear optical medium, said nonlinear optical medium having parallel plane faces, said faces having a zero order half wave plate fixedly attached thereto, said nonlinear optical medium further having an optimum optical entrance angle for every frequency of light, said entrance angle varying as a high order polynomial function of said light wavelength, said entrance angle an incidence angle measured with respect to a normal to either of said parallel plane faces;
• an optical pathway passing through said nonlinear optical medium and each said parallel plane face;
• opposing first and second resonator mirrors arranged at opposite ends of said optical pathway;
• and
• first and second beam alignment means disposed at opposite sides of a nonlinear optical medium between said nonlinear medium and each of said first and second resonator mirrors and lying along said optical pathway, said first and second beam alignment means for directing a collinear light beam onto said first or said second resonator mirrors, said collinear light beam comprising a plurality of about parallel light rays, said first and second beam alignment means arranged to receive and disperse a light beam exiting said nonlinear optical medium, said exiting light beam comprising a plurality of diverging light rays, said first and second beam alignment means de-magnifying a dispersion of said diverging light rays, and spatially converging said diverging light rays to form said collinear beam, said first and second beam alignment means further arranged to receive said collinear beam reflected by said first or said second resonator mirror and to reverse said collinear beam formation to provide thereby a plurality of reflected rays converging into said nonlinear optical medium;
• and
• an optical pumping beam, said optical pumping beam being a narrow-band coherent light beam having a pumping beam frequency and a corresponding pumping beam wavelength, said optical pumping beam entering said nonlinear optical medium at an angle matching said optimum entrance angle to at least a second order approximation of said high order polynomial function, said optical pumping beam converted by an interaction in said nonlinear optical medium to provide converted signal and idler beams having broadened bandwidths, wherein each of said converted signal and idler beams comprises a plurality of output rays having frequencies less than said pumping beam frequency and corresponding wavelengths greater than said pumping beam wavelength, said converted signal beam output rays forming a light output beam, said output light beam cyclically propagating between said first and second resonator mirrors by passing through said first and second beam alignment means and said nonlinear optical medium, said light output beam amplified by an interaction with said pumping beam in said nonlinear optical medium once each cycle.