Two-dimensional coherent beam combination using circular or spiral diffraction grating
View Patent ↗Examples of combining multiple laser beams into a single laser beam by using a circular or spiral diffraction grating are described. The multiple laser beams can be combined coherently or incoherently depending on the geometrical layout of the laser beams.
1. A method of coherently combining a plurality of optical beams, comprising:
arranging a plurality of single-wavelength lasers in a ring-shaped pattern; and
energizing the plurality of single-wavelength lasers to emit the plurality of optical beams such that the plurality of optical beams impinge on a central region of a diffractive element to combine the optical beams to form a single laser beam,
wherein the single laser beam resonates through a laser cavity formed by a partial reflector and the plurality of single-wavelength lasers, and
wherein the diffractive element comprises a spiral grating configured to generate one or more ring-like diffractive patterns.
2. The method of claim 1 , wherein the single-wavelength lasers comprise at least one array of semiconductor diode lasers, fiber lasers, solid-state lasers, gas lasers, or a combination thereof.
3. The method of claim 1 , wherein a spectral bandwidth of the optical beams emitted by the single-wavelength lasers is equal to or less than 5 nanometers.
4. The method of claim 1 , wherein the diffractive element comprises a reflective grating or a transmissive grating.
5. The method of claim 1 , wherein the diffractive element comprises a circular grating configured to generate one or more ring-like diffractive patterns.
6. The method of claim 5 , wherein the one or more ring-like diffractive patterns comprise a continuous or discrete form of one or more ring-like shapes.
7. The method of claim 5 , wherein the one or more ring-like diffractive patterns match with a diffractive angle of the diffractive element at the single-wavelength lasers.
8. The method of claim 1 , wherein the one or more ring-like diffractive patterns comprise a continuous or discrete form of one or more ring-like shapes.
9. The method of claim 1 , wherein the one or more ring-like diffractive patterns match with a diffractive angle of the diffractive element at the single-wavelength lasers.
10. A method of incoherently combining a plurality of optical beams, comprising:
arranging a plurality of multiple-wavelength lasers in a plurality of ring-shaped patterns; and
energizing the plurality of multiple-wavelength lasers to emit the plurality of optical beams such that the plurality of optical beams impinge on a central region of a diffractive element to combine the optical beams to form a single laser beam,
wherein the single laser beam resonates through a laser cavity formed by a partial reflector and the plurality of multiple-wavelength lasers, and
wherein the diffractive element comprises a circular grating configured to generate one or more ring-like diffractive patterns at a plurality of wavelengths.
11. The method of claim 10 , wherein the multiple-wavelength lasers comprise at least one array of semiconductor diode lasers, fiber lasers, solid-state lasers, gas lasers, or a combination thereof.
12. The method of claim 10 , wherein each of the optical beams has at least two separate wavelengths, each of the at least two separate wavelengths having a spectral bandwidth equal to or less than 5 nanometers.
13. The method of claim 10 , wherein the diffractive element comprises a reflective grating or a transmissive grating.
14. The method of claim 10 , wherein the one or more ring-like diffractive patterns comprise a continuous or discrete form of one or more ring-like shapes at the plurality of wavelengths.
15. The method of claim 10 , wherein the one or more ring-like diffractive patterns match with a diffractive angle of the diffractive element at the plurality of multiple-wavelength lasers.
16. The method of claim 10 , wherein the diffractive element comprises a spiral grating configured to generate one or more ring-like diffractive patterns at a plurality of wavelengths.
17. The method of claim 16 , wherein the one or more ring-like diffractive patterns comprise a continuous or discrete form of one or more ring-like shapes at the plurality of wavelengths.
18. The method of claim 16 , wherein the one or more ring-like diffractive patterns match with a diffractive angle of the diffractive element at the plurality of multiple-wavelength lasers.