The invention relates to a microchip laser having a monolithic resonator (1) which has a birefringent laser crystal (2), wherein a laser beam (9) decoupled from the resonator, (1) which has a laser wavelength, exits the resonator (1) along a laser beam axis (12) and the length (L) of the resonator (1) is less than 150 m based on a direction of the laser beam axis (12). The laser crystal (2) has a thickness (D) based on the direction of the laser beam axis (12) such that, in the case of a light beam (16) having the laser wavelength occurring in the direction of the laser beam axis (12) being incident on the laser crystal (2) between the ordinary and extraordinary beam (17, 19), in which the light beam (16) is divided in the laser crystal (2), a phase shift in the range of /2+//4 occurs in a single pass through the laser crystal (2).

Disclosed herein is a single pulse laser apparatus which includes a first mirror and a second mirror disposed at both ends of the single pulse laser apparatus and having reflectivities of a predetermined level or more; a gain medium rotated at a predetermined angle and configured to oscillate a laser beam in a manual mode-locking state; a linear polarizer configured to output a beam having a specific polarized component of the oscillated laser beam; an etalon configured to adjust a pulse width of the oscillated laser beam; and an electro-optic modulator configured to perform Q-switching and single pulse switching.

A laser apparatus according to the present invention may comprise: a plurality of reflection mirrors which form a resonance path so as for light to be amplified by an induced emission; a medium having a first surface which forms a vertical surface with respect to the resonance path, and a second interface which does not form a vertical surface with respect to the resonance path, and absorbs energy from a light source and amplifies and emits the light; and a saturable absorber having a second surface which forms a vertical surface with respect to the resonance path, and a second interface which does not form a vertical surface with respect to the resonance path, and generates ultrashort pulses. The laser apparatus according to the present invention has the effects of cutting a saturable absorber having a specific crystallographic axis to thereby make polarization capacity in one direction advantageous and minimize propagation loss. In addition, the laser apparatus according to the present invention has the effect of maximizing transmittivity maintenance capacity of polarization orientation in one direction by arranging a medium and a saturable medium so as to have a specific inclined plane.

A dual output semiconductor optical amplifier-based tunable fiber laser is provided that can be switched from low to high power and vice versa. The laser system uses bidirectional semiconductor optical amplifier (SOA) for amplification and hence is able to introduce a unique feature of adjustable dual/single output ports.

A housing for an optically pumped semiconductor (OPS) laser resonator is terminated at one end thereof by an OPS-chip. The laser resonator is assembled on a platform with the OPS-chip at one end of the platform. The platform is fixedly attached to a baseplate at the OPS-chip end of the platform. The remainder of the platform extends over the baseplate with a gap between the platform and the baseplate. A pump-laser is mounted directly on the baseplate and delivers pump radiation to the OPS-chip.

A device may include a first photodetector to generate a first current based on an optical power of an optical beam. The device may include a beam splitter to split a portion of the optical beam into a first beam and a second beam. The device may include a wavelength filter to filter the first beam and the second beam. The wavelength filter may filter the second beam differently than the first beam based on a difference between an optical path length of the first beam and an optical path length of the second beam through the wavelength filter. The device may include second and third photodetectors to respectively receive, after the wavelength filter, the first beam and the second beam and to generate respective second currents.

An intra-cavity doubled OPS-laser has a laser-resonator including a birefringent filter (BRF) for coarse wavelength-selection, and an optically nonlinear (ONL) crystal arranged for type-II frequency-doubling and fine wavelength-selection. Laser-radiation circulates in the laser-resonator at one of a range of fundamental wavelengths dependent on the resonator length. The ONL crystal has a transmission peak-wavelength dependent on the crystal temperature. Reflection of circulating radiation from the BRF is monitored. The reflection is at a minimum when the ONL crystal transmission-peak wavelength is at the circulating radiation wavelength. The temperature of the ONL crystal is selectively varied to maintain the monitored reflection at about a minimum.

A narrow band laser apparatus may include: a laser resonator; a pair of discharge electrodes; a power supply; a first wavelength measurement device configured to output a first measurement result; a second wavelength measurement device configured to output a second measurement result; and a control unit. The control unit calibrates the first measurement result, based on a difference between the second measurement result derived when the control unit controls the power supply to apply a pulsed voltage to the pair of discharge electrodes with a first repetition frequency and the second measurement result derived when the control unit controls the power supply to apply the pulsed voltage to the pair of discharge electrodes with a second repetition frequency, the second repetition frequency being higher than the first repetition frequency.

A housing for an optically pumped semiconductor (OPS) laser resonator is terminated at one end thereof by an OPS-chip. The laser resonator is assembled on a platform with the OPS-chip at one end of the platform. The platform is fixedly attached to a baseplate at the OPS-chip end of the platform. The remainder of the platform extends over the baseplate with a gap between the platform and the baseplate. A pump-laser is mounted directly on the baseplate and delivers pump radiation to the OPS-chip.

In a method, energy is supplied to a first gas discharge chamber of a first stage until a pulsed amplified light beam is output from the first stage and directed toward a second stage. While the energy is supplied to the first gas discharge chamber: a value of an operating parameter of the first gas discharge chamber is measured; it is determined whether to adjust an operating characteristic of the first gas discharge chamber based on the measured value; and, the operating characteristic of the first gas discharge chamber is adjusted if it is determined that the operating characteristic of the first gas discharge chamber should be adjusted. After it is determined that the operating characteristic of the first gas discharge chamber no longer should be adjusted, then an adjustment procedure is applied to an operating characteristic of a second gas discharge chamber of the second stage.