A laser device includes: a plurality of laser diodes that emit laser beams having different wavelengths; a partial reflection mirror that resonates the plurality of laser beams emitted by the plurality of laser diodes; and a wavelength dispersion element that causes the plurality of laser beams incident from the plurality of laser diodes in different orientations of optical axes of the laser beams to travel to the mirror with the optical axes aligned. Each of the plurality of laser diodes is integrally formed with an adjustment component that is rotatable around an emission end of the laser diode.

A photonic-based microwave generator includes a mode-locked laser that generates an optical pulse train, a feedback photodiode that samples the optical pulse train, and a servo amplifier that processes the photodiode output into a servo signal. The servo signal controls the mode-locked laser to suppress relative intensity noise on the optical pulse train. The microwave generator may also include a microwave photodiode for converting the optical pulse train into a microwave signal. The microwave generator may also include a second servo amplifier that processes a low-frequency output of the microwave photodiode into a second servo signal that drives an optical modulator that modulates the optical pulse train. The microwave photodiode, optical modulator, and servo amplifier form a feedback loop that suppresses amplitude noise on the microwave signal. By reducing amplitude noise and relative intensity noise, phase noise caused by amplitude-to-phase noise conversion is minimized.

A laser device includes: a plurality of laser diodes that emit laser beams having different wavelengths; a partial reflection mirror that resonates the plurality of laser beams emitted by the plurality of laser diodes; and a wavelength dispersion element that causes the plurality of laser beams incident from the plurality of laser diodes in different orientations of optical axes of the laser beams to travel to the mirror with the optical axes aligned. Each of the plurality of laser diodes is integrally formed with an adjustment component that is rotatable around an emission end of the laser diode.

A spectral beam combining system includes a plurality of input fibers and a prism having a curved input surface. The plurality of input fibers are attached to the curved input surface. The spectral beam combining system also includes an immersion grating defined on a second surface of the prism, a protective cap disposed over the immersion grating, and an output surface.

Apparatus, systems and methods to spectrally beam combine a group of diode lasers in an external cavity arrangement. A dichroic beam combiner or volume Bragg grating beam combiner is placed in an external cavity to force each of the diode lasers or groups of diode lasers to oscillate at a wavelength determined by the passband of the beam combiner. In embodiments the combination of a large number of laser diodes in a sufficiently narrow bandwidth to produce a high brightness laser source that has many applications including as to pump a Raman laser or Raman amplifier.

A frequency double or mixing laser includes a laser pump, a rear optical element, a Brewster window, a laser generator medium, an output coupler and a nonlinear crystal located inside the resonator cavity. The nonlinear crystal may be located inside the resonator cavity before the output coupler. The laser may further include at least one optical element that controls the phase or/and the amplitude of the fundamental laser beam to a high-order.

A radio-frequency excited carbon dioxide (CO.sub.2) or carbon monoxide (CO) gas laser includes two electrodes, which have passivated surfaces, within a sealed housing. Features in a ceramic slab or a ceramic cylinder located between the electrodes define a gain volume. Surfaces of the ceramic slab or the ceramic cylinder are separated from the passivated surfaces of the electrodes by small gaps to prevent abrasion thereof. Reducing compressive forces that secure these components within the housing further reduces abrasion, thereby extending the operational lifetime of the gas laser.

The present invention provides a way to use anisotropic laser gain media to make a laser that can lase in two longitudinal modes at different wavelengths with orthogonal polarizations. The two longitudinal mode (LM) laser output can be separated to generate two single LM outputs. This type of lasers can also be used to generate low noise continuous wave (CW) harmonics through intracavity harmonic generation.

To prevent an output decrease of laser light due to impurities formed in a Q switch. A laser machining device includes a Q-switch housing section configured by housing a Q switch and a first mirror and a wavelength converting section including a housing in which a transmission window section capable of transmitting a fundamental wave is formed, the wavelength converting section being configured by airtightly housing, with an internal space surrounded by the housing, at least a first wavelength conversion element, a second wavelength conversion element, and a second mirror. A resonator forming a resonant optical path passing through the transmission window section is configured by the first mirror in the Q-switch housing section and the second mirror in the wavelength converting section.

A laser apparatus that can generate a high-quality laser beam is provided. The laser apparatus is provided with a laser medium and an insulation layer. The laser medium has a first surface and a second surface. Incident laser light is incident on the first surface. The second surface totally reflects the incident laser light that is incident to the second surface at an incident angle equal to or larger than a critical angle. The insulation layer covers a second area of the second surface that surrounds a first area of the second surface, the first area totally reflecting the incident laser light. The laser medium is exposed in the first area.