A heat sink assembly may include a first cooling stack. The first cooling stack may include a silver-diamond composite material. The heat sink assembly may include a second cooling stack. The second cooling stack may include the silver-diamond composite material. The heat sink assembly may include a crystal rod. The crystal rod may be an ytterbium-doped, yttrium-aluminum-garnet laser medium. The crystal rod may be at least partially sandwiched by the first cooling stack and the second cooling stack.

A modular solid-state laser comprises a diode-laser pump module and a laser-enclosure. The diode-laser pump module produces a collimated beam of laser-radiation for pumping a gain-element within the laser-enclosure. The beam of pump laser-radiation is focused into the gain-element by optics located within the laser-enclosure. The diode-laser pump module can be replaced or exchanged without realigning optics located within the laser-enclosure.

A short-pulse, narrowband, line-selectable and tunable solid-state laser is described. The device requires a pump source, an active solid-state laser medium, an enclosing cavity, mirrors to contain the light, a method of removing the pulse from the cavity, a wavelength selection system, and a laser linewidth narrowing system. One implementation of this is an Er:YAG laser, side pumped by semiconductor lasers in the erbium absorption band near 1475 nm, with an intracavity etalon and a switchable spectral filter. To remove the pulse from the cavity, cavity dumping issues, which assures constant pulse energy and pulse length over a range of repetition rates, in this case from 100 Hz to 20 kHz. Line selection is obtained by use of wavelength filters and fine tuning with an etalon, which also acts as the linewidth narrowing system.

An optical resonator may be provided. The optical resonator may comprise a laser system with an adjustable optical path length. The optical resonator may include a back mirror. The back mirror may include a first back mirror surface and a second back mirror surface. The first back mirror surface and may provide a first optical path length for the optical resonator if the first back mirror surface may be included in the optical path. The second back mirror may provide a second optical path length for the optical resonator if the second back mirror surface is included in the optical path.

An optical oscillator according to an embodiment includes a first reflecting portion that transmits light having a first wavelength and reflects light having a second wavelength different from the first wavelength, a second reflecting portion that forms an unstable resonator together with the first reflecting portion and reflect light having the second wavelength, a laser medium that is disposed between the first reflecting portion and the second reflecting portion and emits light having the second wavelength due to incidence of light having the first wavelength, and a saturable absorption portion disposed on a side opposite to the first reflecting portion when viewed from the laser medium in the one direction, the first reflecting portion includes an incidence surface on which light having the first wavelength is incident, on a side opposite to the laser medium, a size of the second reflecting portion is smaller than a size of the first reflecting portion when viewed in the one direction, at least a part of a surface of the saturable absorption body on the side opposite to the laser medium includes a curved region curved toward the laser medium side, and the second reflecting portion is a dielectric multilayer film provided in the curved region.

A flash lamp 32 excites a laser rod 31. A Q switch 35 which changes the loss of the optical resonator according to the voltage applied is inserted on the optical path of a pair of mirrors 33 and 34 forming the optical resonator. An optical path shutter 39 is provided on the optical path of laser emission light. In a first operation mode in which laser emission is performed, the optical path shutter 39 is opened and the voltage applied to the Q switch 35 is changed from a high voltage to, for example, 0 V to emit pulsed laser light after the flash lamp 32 excites the laser rod 31. In a second operation mode in which the laser emission is interrupted and waited for, the optical path shutter 39 is closed and the voltage applied to the Q switch 35 is, for example, 0 V.

In a solid-state laser device and a photoacoustic measurement device including the solid-state laser device, the distance between a laser rod and a flash lamp is narrowed. A shielding lid shields mirrors and an optical path of laser light from the outside. A first portion of a frame body of a laser chamber is exposed from the shielding lid. A flash lamp stored in the frame body of the laser chamber is able to be removed from and inserted into the first portion of the frame body. A thin film portion having a thickness smaller than the thickness of other portions of the shielding lid is provided in at least a part of a region of the shielding lid covering the optical path of a light beam on the outside in a longitudinal direction from the first portion of the frame body of the laser chamber.

A MOPA laser system that includes a seed laser configured to output pulsed laser light, an amplifier configured to receive and amplify the pulsed laser light emitted by the seed laser; and a pump laser configured to deliver a pump laser beam to both the seed laser and the amplifier.

A monolithic photonic resonator includes a bulk optic with first and second superpolished facets, and a high-reflectivity coating applied to each of the first and second superpolished facets. The superpolished facets form an optical resonator. The bulk optic is a single piece of an optical material that is solid, i.e., has no internal holes, gaps, or pockets. The bulk optic therefore serves as an intraresonator optical medium while still supporting a finesse of 10,000 or more. The superpolished facets may be counterfacing to form a Fabry-Perot cavity. Alternatively, the bulk optic may include forms one or more additional facets off of which light inside the bulk optic undergoes total internal reflection. The monolithic photonic resonator may be mounted in a support structure that minimizes the overall vibration sensitivity of the resonator's resonance frequency.

A laser system includes a first laser cavity to output a laser light along a first path, a first mirror to receive the laser light from the first laser cavity, and redirect the laser light along a second path that is different than the first path, a second mirror to receive the laser light from the first mirror, and redirect the laser light along a third path that is different than the first path and the second path, a beam splitter located at a first position on the third path, a beam combiner located at a second position on the third path; and a coupling lens assembly, the coupling lens assembly including a lens located at a third position on the third path, wherein the coupling lens assembly moves the lens in x-, y-, and x-directions.