A passively, Q-switched laser is described. The laser may operate at an eye-safe lasing wavelength of 1.34 microns and use a gain element of Nd:YVO.sub.4 and a saturable absorber element of V:YAG with a space separating the gain element and saturable absorber element. The Q-switched laser is pumped by a grating stabilized laser diode. The laser may be used in laser ranging applications.

Methods and systems for controlling pressure in a cavity of a light source are provided. One system includes a barometric pressure sensor configured for measuring pressure in a cavity of a light source. The system also includes one or more gas flow elements configured for controlling an amount of one or more gases in the cavity. In addition, the system includes a control subsystem configured for comparing the measured pressure to a predetermined range of values for the pressure and, when the measured pressure is outside of the predetermined range, altering a parameter of at least one of the one or more gas flow elements based on results of the comparing.

A laser medium unit 10 in a laser beam amplification device includes a plurality of laser media 14. A cooling medium flow path F1 is provided around the laser medium unit 10 to cool the laser medium unit 10 from outside. A sealed space between the laser media 14 is filled with gas or liquid, and a laser beam for passing through the sealed space is not interfered by a cooling medium flowing outside. Therefore, a fluctuation of an amplified laser beam is prevented, and a quality such as stability and focusing characteristics of the laser beam is improved.

The purpose of the present invention is to provide a laser device that makes it possible to minimize condensation in a closed space by means of a simple structure. This laser device comprises a closed space (S4) in which an optical system (31) for transmitting laser light is accommodated and a dew point adjustment flow path (5) of which at least one part is a flow path wall section formed from a transmissive material (51) through which gas molecules including water vapor are transmitted and dust and oil mist are not transmitted. The transmissive material (51) separates the interior of the dew point adjustment flow path (5) and the closed space (S4).

Various embodiments of a multi-laser system are disclosed. In some embodiments, the multi-laser system includes a plurality of lasers, a plurality of laser beams, a beam positioning system, a thermally stable enclosure, and a temperature controller. The thermally stable enclosure is substantially made of a material with high thermal conductivity such as at least 5 W/(m K). The thermally stable enclosure can help maintain alignment of the laser beams to a target object over a range of ambient temperatures. Various embodiments of an optical system for directing light for optical measurements such laser-induced fluorescence and spectroscopic analysis are disclosed. In some embodiments, the optical system includes a thermally conductive housing and a thermoelectric controller, a plurality of optical fibers, and one or more optical elements to direct light emitted by the optical fibers to illuminate a flow cell. The housing is configured to attach to a flow cell.

A passively, Q-switched laser operating at an eye safe wavelength of between 1.2 and 1.4 microns is described. The laser may operate at a lasing wavelength of 1.34 microns and use a gain element of Nd:YVO.sub.4 and a saturable absorber element of V:YAG. The position of the resonator axial mode spectrum relative to a gain peak of the gain element is controlled to yield desired characteristics in the laser output.

According to one embodiment, an illumination device includes a light guide including an upper surface, a lower surface and a light entering surface, a first light emitting portion, a second light emitting portion, and a third light emitting portion. A first surface, a second surface, a third surface and a fourth surface of the upper surface are arranged in this order in a first direction. A width of the first surface is less than a width of the second surface, and the width of the second surface is less than a width of the third surface. An angle between the light entering surface and the first surface is an acute angle. The first light emitting portion, the second light emitting portion and the third light emitting portion face the light entering surface.

There are provided high power, high brightness solid-state laser systems that maintain initial beam properties, including power levels, and do not have degradation of performance or beam quality, for at least 10,000 hours of operation. There are provided high power, high brightness solid-state laser systems containing Oxygen in their internal environments and which are free from siloxanes.

The present disclosure is intended to provide a smaller laser oscillator that can be manufactured at a reduced cost. Provided is a laser oscillator for producing a laser beam, the laser oscillator including: a housing; a transformer arranged in the housing, connected to a power supply, and supplying power to a first device that consumes a predetermined amount of power; and a power factor correction unit arranged in the housing, having a power factor correction circuit that brings a power factor close to 1, connected to the power supply, and supplying power to a second device that consumes a relatively larger amount of power than the first device.

A high air-tightness device is provided with a bottom plate (1), a frame body wall (2) and a shell body cover (3). The materials of said parts are one and more of metal, glass and ceramic, and the junctions among the parts are sealed by extruding a hollow-core metal sealing ring (12) by thread. The device is provided with one and more of a window glass (17), a pipeline (10), a pipeline interface, an openable and closable valve (11), an electrode communicating inside with outside and a threaded opening, and the device is connected and sealed by extruding the hollow-core metal sealing ring using the internal or external threaded part to move straight or rotate; or the device is pre-sealing formed by one and more of a metal solder welding processing technique, a metal welding processing technique, a glass welding processing technique and a sintering ceramic formed processing technique. The materials of each part for isolating inside from outside during the sealing are one and more of metal, glass and ceramic. Vacuum, special gas and liquid can be sealed within the high air-tightness device for a long time. The high air-tightness device is easy to be opened and re-sealed, and has easy maintenance and low cost.