Self-optimizing beam combining apparatus and method for semiconductor laser beam quality

A self-optimizing beam combining apparatus for semiconductor laser beam quality, comprising:

• a semiconductor laser array, a fast axis collimator array, a slow axis collimator array, a mirror array, a volume Bragg grating array, and an external cavity mirror, wherein
• the semiconductor laser array emits a beam array with identical wavelengths, wherein the beam array sequentially passes through the fast axis collimator array, the slow axis collimator array, the mirror array, the volume Bragg grating array, and the external cavity mirror before being emitted;
• the fast axis collimator array reduces a divergence angle of the beam array in a fast axis direction, the slow axis collimator array reduces a divergence angle of the beam array in a slow axis direction, the mirror array reflects the beam array emitted from the slow axis collimator array to the volume Bragg grating array, the volume Bragg grating array diffracts the beam array and causes a portion of laser light within an entire semiconductor laser spectrum that satisfies a Bragg diffraction condition to be incident on the external cavity mirror, and the external cavity mirror feeds back the laser light satisfying the Bragg diffraction condition sequentially through the volume Bragg grating array, the mirror array, the slow axis collimator array, and the fast axis collimator array along an original path back into chips of respective semiconductor lasers in the semiconductor laser array, achieving mode competition and automatic wavelength adjustment;
• the adjusted beam array is then combined again by sequentially passing through the fast axis collimator array, the slow axis collimator array, the mirror array, and the volume Bragg grating array;
• and a combined beam is output through the external cavity mirror;
• the semiconductor laser array comprises at least two semiconductor lasers;
• the fast axis collimator array comprises at least two fast axis collimators, with each of the fast axis collimators correspondingly arranged for each of the semiconductor lasers;
• the slow axis collimator array comprises at least two slow axis collimators, with each of the slow axis collimators correspondingly arranged for each of the semiconductor lasers;
• the mirror array comprises at least two mirrors, with each of the mirrors correspondingly arranged for each of the semiconductor lasers;
• and
• the volume Bragg grating array comprises at least two volume Bragg gratings, wherein each of the volume Bragg gratings is correspondingly arranged for each of the mirrors, and a wavelength and incident laser angle of a target beam for each of the volume Bragg gratings satisfy the following equation:
• ❘
• "\[LeftBracketingBar]"
• cos
• ⁢
• ϕ
• 0
• ❘
• "\[RightBracketingBar]"
• =
• λ
• 2
• ⁢
• Λ
• ⁢
• n
• av
• ;
• wherein do represents the incident laser angle for the volume Bragg gratings;
• Λ represents a grating period;
• nav represents a grating refractive index;
• and λ represents the wavelength of the target beam.