Optical field transformation methods and systems
A method of performing coherent transformations of optical fields includes forming a far field distribution of the input optical field. A fraction of the formed far field is diffracted by producing localized discontinuities within said far field. A Fraunhofer diffraction pattern of the diffracted optical field is formed. The Fraunhofer diffraction pattern is modified by producing localized optical path differences within the Fraunhofer diffraction pattern. The transformed output optical field is produced in the far field with respect to the modified Fraunhofer diffraction pattern.
1. A method of performing coherent transformations of optical fields, comprising the following steps:
forming a far field distribution of the input optical field;
diffracting a fraction of the formed far field by producing localized discontinuities within said far field;
forming a Fraunhofer diffraction pattern of the diffracted optical field;
modifying the Fraunhofer diffraction pattern by producing localized optical path differences within the Fraunhofer diffraction pattern; and
producing the transformed output optical field in the far field with respect to the modified Fraunhofer diffraction pattern.
2. The method according to claim 1 , wherein diffraction of said far field is achieved by producing at least one of localized phase discontinuities and localized amplitude discontinuities.
3. The method according to claim 1 , further comprising adjusting the localized discontinuities diffracting the formed far field.
4. The method according to claim 3 , further comprising adjusting at least one of lateral dimensions, lateral shapes, and lateral positions of the localized discontinuities diffracting the far field.
5. The method according to claim 3 , further comprising adjusting at least one of localized optical phase discontinuities and localized amplitude discontinuities.
6. The method according to claim 1 , further comprising producing said localized discontinuities in the focal plane of an optical system.
7. The method according to claim 1 , further comprising adjusting the produced localized optical path differences within said Fraunhofer diffraction pattern.
8. The method according to claim 1 , further comprising producing the localized optical path differences within said Fraunhofer diffraction pattern to reduce optical phase discontinuities within said Fraunhofer diffraction pattern.
9. The method according to claim 1 , further comprising producing localized optical path differences within said Fraunhofer diffraction pattern to modify at least one of spatial distributions and lateral positions of the transformed output field.
10. The method according to claim 1 , further comprising adjusting the transformed output optical field by modifying the lateral extent of the optical field within the Fraunhofer diffraction region.
11. The method according to claim 1 , further comprising producing the transformed optical field in the focal plane of a lens with positive optical power focusing the modified Fraunhofer diffraction pattern.
12. The method according to claim 11 , further comprising modifying the lateral size of the transformed optical field by changing the focal lengths of the optical components with positive optical powers.
13. The method according to claim 1 , further comprising adjusting the localized discontinuities diffracting the far field to reduce the influence of the input field distortions onto the transformed output field.
14. The method according to claim 1 , further comprising adjusting the localized optical path differences within the Fraunhofer diffraction pattern to reduce the influence of the input field distortions onto the transformed output field.
15. The method according to claim 1 , further comprising producing additional optical path modifications of the input optical field prior to forming the far field distribution of the input optical field.