Frequency-converted light source

1. A light source comprising:

a light emitting element that is configured to emit a non-diffraction limited input light beam;

a nonlinear frequency conversion (NLFC) component that exhibits walkoff and performs second harmonic generation whereby at least a portion of an output beam outputted by the NLFC component has twice a frequency of the non-diffraction limited input light beam; and

an optical component positioned to receive the non-diffraction limited input light beam and configured to converge the non-diffraction limited input light beam into the NLFC component;

wherein the light emitting element is configured to emit the non-diffraction limited input light beam having a beam quality factor in at least one plane of the input beam that is greater than 2 (M 2 >2); and

wherein the light emitting element is a laser diode including Al y In x Ga 1-x-y N (0≦x≦1, 0≦y≦1) semiconductor materials, and one dimension of an emission region of the laser diode is at least 5 μm.

2. The light source of claim 1 , wherein a wavelength of the non-diffraction limited input light beam is 400-600 nm and a wavelength of the output beam is 200-300 nm.

3. The light source of claim 1 , wherein the light emitting element is configured to emit the non-diffraction limited input light beam having a beam quality factor in a plane parallel to a non-walkoff plane of the NLFC component that is greater than 3 (M y 2 >3).

4. The light source of claim 1 , wherein the light emitting element is configured to emit the non-diffraction limited input light beam having a beam quality factor in a plane parallel to a non-walkoff plane of the NLFC component that is greater than 2 (M y 2 >2).

5. The light source of claim 1 , wherein the optical component is configured to converge the non-diffraction limited input light beam with a convergence half-angle between 0.9° and 10.5°.

6. The light source of claim 5 , wherein the optical component is configured to converge the non-diffraction limited input light beam to have a convergence half-angle characterized in that a beam waist radii of the non-diffraction limited input light beam, after propagation through an input surface of the NLFC component which is not planar or does not have a surface normal parallel to the propagation direction of the non-diffraction limited input light beam, are approximately equal to a beam waist radii of the non-diffraction limited input light beam which would form in the NLFC component after propagation of a non-diffraction limited input light beam with a convergence half-angle in air into an input surface of the NLFC component that is a planar surface and the direction normal to said surface is parallel to the propagation direction of the non-diffraction limited input light beam.

7. The light source of claim 1 , wherein ε=1.0 and the optical component is configured to converge the non-diffraction limited input light beam with a convergence half-angle of 2.1±1°.

8. The light source of claim 1 , wherein the NLFC component includes a β-BaB 2 O 4 crystal.

9. The NLFC device of claim 1 , wherein the light emitting element is configured to emit the non-diffraction limited input light beam having a beam quality factor in at least one plane of the non-diffraction limited input light beam that is greater than 3 (M 2 >3).

10. The light source of claim 1 , wherein:

the NLFC component includes a β-BaB 2 O 4 crystal;

the optical component is configured to converge the non-diffraction limited input light beam with a convergence half-angle in air in the non-walkoff place of the NLFC component between 0.9° and 10.5°;

the light emitting element is configured to emit the non-diffraction limited input light beam having a beam quality factor in a plane parallel to a non-walkoff plane of the NLFC component that is greater than 3 (M y 2 >3); and

a wavelength of the non-diffraction limited input light beam is 400-600 nm and a wavelength of the output beam is 200-300 nm.

11. The light source of claim 10 , wherein the output beam has an output power of greater than 0.002 mW and a wavelength between 210 nm and 230 nm.