A laser assembly (1710) for generating an assembly output beam (1712) includes a laser subassembly (1716) including a first laser module (1716A) and a second laser module (1716B), a transform assembly (1744), and a beam combiner (1746). The first laser module (1716A) emits a plurality of spaced apart first laser beams (1720A). The second laser module (1716B) emits a plurality of spaced apart second laser beams (1720B). The transform assembly (1744) is positioned in a path of the laser beams (1720A) (1720B). The transform assembly (1744) directs the laser beams (1720A) (1720B) to spatially overlap at a focal plane of the transform assembly (1744). The beam combiner (1746) is positioned at the focal plane that combines the lasers beams (1720A) (1720B) to provide a combination beam. The laser beams (1720A) (1720B) directed by the transform assembly (1744) impinge on the beam combiner (1746) at different angles.

In accordance with various embodiments, a multi-wavelength beam output is formed by stabilizing beams each to a unique wavelength with a stabilizing dispersive element, which reflects a portion of the beam back to its emitter to stabilize the beam and transmits the stabilized beam. The stabilized beams are then transmitted to a combining dispersive element that combines the stabilized beams into the multi-wavelength beam output.

In various embodiments, laser resonator modules produce output beams via manipulation of input beams on opposite sides of the module. The input beams are emitted by one or more beam emitters that may be cooled using a liquid coolant cavity. The liquid coolant cavity may be isolated from optical elements utilized to manipulate the input beams, at least in part, by an isolation wall protruding from the base plate of the resonator module.

A swept light source of the present invention keeps a coherence length of an output beam long over an entire sweep wavelength range. A gain of a gain medium is changed with time in response to a wavelength sweep and the coherence length is kept maximum. The gain of the gain medium is kept close to a lasing threshold and an unsaturated gain range of the gain medium is narrowed over the entire sweep wavelength range. An SOA current waveform data acquiring method of driving while keeping the coherence length long, a novel coherence length measuring method, and an optical deflector suitable for the swept light source are also disclosed.

In various embodiments, one or more optical elements are utilized to alter the numerical aperture of a radiation beam received from an optical fiber in order to accommodate the properties of a downstream collimator within a laser delivery head.

In a WBC system of the present disclosure, an LD bar array constituted by a plurality of LD bars is configured such that a main axis direction of an off-angle of at least one LD bar is reversed with respect to a main axis direction of an off-angle of the other LD bar. By doing so, even in the LD bar in which a wavelength distribution in a wafer exists, a difference between a designed lock wavelength and a gain peak wavelength can be kept within a range where an LD oscillation due to an external resonance is possible for all emitters in the LD bar, thereby an output in the WBC system can be maximized.

A light source device including: a first light source configured to coaxially combine a plurality of first laser beams, each having a peak wavelength within a first wavelength range, to thereby generate and emit a first wavelength-combined beam; a second light source configured to coaxially combine a plurality of second laser beams, each having a peak wavelength within a second wavelength range that defines a range of peak wavelengths shorter than the peak wavelengths in the first wavelength range, to thereby generate and emit a second wavelength-combined beam; and a wavelength filter configured to coaxially combine the first wavelength-combined beam and the second wavelength-combined beam to thereby generate and emit a third wavelength-combined beam.

A laser light source device includes: a first light emitter that emits a first laser beam; a second light emitter that emits a second laser beam; an optical element that converges the first laser beam and the second laser beam; a wavelength dispersing element on which the first laser beam and the second laser beam from the optical element are incident, and which causes optical axes of the first laser beam and the second laser beam to coincide with one another, and then transmits the first laser beam and the second laser beam; and a partially reflecting mirror that returns portions of the first laser beam and the second laser beam from the wavelength dispersing element by reflection, and transmits remaining portions of the first laser beam and the second laser beam that have exited from the wavelength dispersing element. The reflectance of the partially reflecting mirror is wavelength-dependent.

A wavelength beam combining device includes: a laser diode stack comprising a plurality of stacked laser diode bars, wherein each laser diode bar comprises a plurality of laser diodes arranged laterally in a row; a light condensing member; a diffraction grating; a resonator mirror; and an output control unit configured to control each of the laser diode bars such that, in every possible mode in which the output control unit controls each laser diode bar to operate such that one or more of the laser diodes emit laser beams and one or more of the laser diodes do not emit laser beams, the one or more laser diodes that emit laser beams are located inward of the one or more laser diodes that do not emit laser beams.

A semiconductor laser device includes: a plurality of semiconductor light emitting elements each of which emits a light beam; a wavelength dispersion element (a diffraction grating) that emits the light beam emitted from each of the plurality of semiconductor light emitting elements to pass through one optical path; a pedestal that supports the wavelength dispersion element; and a presser that fixes the wavelength dispersion element to the pedestal by pressing the wavelength dispersion element. The presser presses on the wavelength dispersion element in a direction perpendicular to a surface on which with the wavelength dispersion element is provided.