Multi-Channels coherent beam combining (CBC) using a mechanism for phase and/or polarization locking that uses a reference optical beam and an array of optical detectors each detector being configured and located to detect overall intensity of an optical interference signal caused by interfering of the reference beam and a beam of the respective channel, where the fast intensity per-channel detection allows simultaneous and quick phase/polarization locking of all channels for improving beam combining system performances.

A tip/tilt/piston (“TTP”) MEMS MMA is used to provide coherent beam combination (CBC) such that the combined beam behaves as if it were emitted from a single aperture laser, but with higher brightness than can be obtained from an individual laser. Piston actuation of the mirrors is used to adjust the phase of individual amplified laser beams and maintain a zero phase difference across all of the amplified laser beams. Tip/Tilt actuation of the mirrors is used to steer the phase-adjusted amplified laser beams to form a coherent output laser beam. Additional TTP actuation can be used to oversample and superimpose Adaptive Optics correction or focusing/defocusing on the beam. A multi-spectral system may be implemented with a common MEMS MMA to produce a spectrally beam combined, multi-channel coherent laser beam.

A hybrid coherent beam combining (CBC) and spectral beam combining (SBC) fiber laser amplifier system including a beam shaper array assembly and a beam source that provides a plurality of beams having a low fill factor profile. The assembly includes an input beam shaper array having a plurality of rectilinear input cells positioned adjacent to each other that are shaped to cause the beam to expand as it propagates away from the input array to be converted from the low fill factor profile to a high fill factor profile. The assembly further includes an output beam shaper array having a plurality of output cells positioned adjacent to each other that are shaped to cause the beam to stop expanding so that the output array provides a plurality of adjacent beams with minimal overlap and a minimal gap between the beams.

Various implementations of the invention compensate for “phase wandering” in tunable laser sources. Phase wandering may negatively impact a performance of a lidar system that employ such laser sources, typically by reducing a coherence length/range of the lidar system, an effective bandwidth of the lidar system, a sensitivity of the lidar system, etc. Some implementations of the invention compensate for phase wandering near the laser source and before the output of the laser is directed toward a target. Some implementations of the invention compensate for phase wandering in the target signal (i.e., the output of the laser that is incident on and reflected back from the target). Some implementations of the invention compensate for phase wandering at the laser source and in the target signal.

Various implementations of the invention compensate for “phase wandering” in tunable laser sources. Phase wandering may negatively impact a performance of a lidar system that employ such laser sources, typically by reducing a coherence length/range of the lidar system, an effective bandwidth of the lidar system, a sensitivity of the lidar system, etc. Some implementations of the invention compensate for phase wandering near the laser source and before the output of the laser is directed toward a target. Some implementations of the invention compensate for phase wandering in the target signal (i.e., the output of the laser that is incident on and reflected back from the target). Some implementations of the invention compensate for phase wandering at the laser source and in the target signal.

A light-scanning endoscope is provided with: a light-scanner that causes an optical fiber to be vibrated; a controller that causes light to be emitted from the optical fiber with the same phase as the vibrations; an adjusting unit that adjusts a distortion correction amount on the basis of a shape of a row of irradiation positions of the light on an imaging subject; and a phase correcting unit that corrects the phase in which the light is emitted on the basis of the adjusted distortion correction amount.

This application describes a wavelength-tunable laser apparatus, which reduces complexity of wavelength tuning of a laser. The laser includes a reflective gain unit, an optical phase shifter, a coupler, and a passive filter unit array. Furthermore, an output port of the reflective gain unit is connected to an input port of the optical phase shifter, an output port of the optical phase shifter is connected to an input port of the coupler, a first output port of the coupler is connected to an input port of the passive filter unit array, and a second output port of the coupler is an output port of the laser. The passive filter unit array includes a plurality of passive filter units, where any two of the plurality of passive filter units have different wavelength tuning ranges, and each filter unit has a linearly tunable wavelength.

A hybrid coherent beam combining (CBC) and spectral beam combining (SBC) fiber laser amplifier system including a beam shaper array assembly and a beam source that provides a plurality of beams having a low fill factor profile. The assembly includes an input beam shaper array having a plurality of rectilinear input cells positioned adjacent to each other that are shaped to cause the beam to expand as it propagates away from the input array to be converted from the low fill factor profile to a high fill factor profile. The assembly further includes an output beam shaper array having a plurality of output cells positioned adjacent to each other that are shaped to cause the beam to stop expanding so that the output array provides a plurality of adjacent beams with minimal overlap and a minimal gap between the beams.

A coherently beam combining (CBC) fiber laser amplifier system including beam shaper array assembly and a beam source that provides a plurality of beams having a low fill factor profile. The assembly includes an input beam shaper array having a plurality of input cells positioned adjacent to each other that are shaped to cause the beam to expand as it propagates away from the input array to be converted from the low fill factor profile to a high fill factor profile and cause the profile to taper to a lower value at a perimeter of each input array cell. The assembly further includes an output beam shaper array having a plurality of output cells positioned adjacent to each other that are shaped to cause the beam to stop expanding so that the output array provides a plurality of adjacent beams with minimal overlap and a minimal gap between the beams.

A spectral beam combining (SBC) fiber laser amplifier system including a beam shaper array assembly and a beam source that provides a plurality of beams having a low fill factor profile. The assembly includes an input beam shaper array having a plurality of input cells positioned adjacent to each other that are shaped to cause the beams to expand as they propagates away from the input array to be converted from the low fill factor profile to a high fill factor profile and be tapered to a lower value at a perimeter of each input array cell. The assembly further includes an output beam shaper array having a plurality of output cells positioned adjacent to each other that are shaped to cause the beams to stop expanding so that the output array provides a plurality of adjacent beams with minimal overlap and a minimal gap between the beams.