A light based treatment device comprises an optical arrangement at a light exit end of an optical fiber. The optical arrangement includes a master oscillator power amplifier based on a semiconductor optical laser and a crystal optical amplifier. In this way, the peak power provided along the optical fiber can be reduced to prevent damage to the optical fiber, while enabling a sufficiently high pulse power to be delivered for tissue treatment.

A light based treatment device comprises an optical arrangement at a light exit end of an optical fiber. The optical arrangement includes a master oscillator power amplifier based on a semiconductor optical laser and a crystal optical amplifier. In this way, the peak power provided along the optical fiber can be reduced to prevent damage to the optical fiber, while enabling a sufficiently high pulse power to be delivered for tissue treatment.

A light based treatment device comprises an optical arrangement at a light exit end of an optical fiber. The optical arrangement includes a master oscillator power amplifier based on a semiconductor optical laser and a crystal optical amplifier. In this way, the peak power provided along the optical fiber can be reduced to prevent damage to the optical fiber, while enabling a sufficiently high pulse power to be delivered for tissue treatment.

Laser devices include a light source that emits a laser beam, an optical system that concentrates the laser beam emitted from the light source, an optical window through which the laser beam exited from the optical system passes, a housing that accommodates the optical system, and an optical window holding member fixed to the housing. The optical window holding member holds the optical window. In the first laser device, the optical window has a face or a protruding face through which the laser beam passes. When the optical window has the face, the face is flush with an edge of the optical window holding member and a film is formed on the face. When the optical window has the protruding face, the protruding face protrudes with reference to the edge of the optical window holding member and a film is formed on the protruding face.

A Cr:YAG sintered body including Al, Y, Cr, Ca, Mg, Si, and O, and component contents in the sintered body satisfying conditional expressions of 1) to 3) below, provided in the Conditional expression, each chemical symbol represents a component content (atppm).

|(Y+Ca)/(Al+Cr+Si+Mg)−0.6|<0.001;  1)

0≤(Ca+Mg)−(Cr+Si)≤50 atppm; and  2)

50≤Si≤500 atppm  3)

The embodiment of the present invention is to provide a Cr:YAG sintered body which exhibits high transparency and has a high Cr.sup.4+ conversion ratio, and its production method.

Systems and methods for imaging in the short wave infrared (SWIR), photodetectors with low dark current and associated circuits for reducing dark currents and methods for generating image information based on data of a photodetector array. A SWIR imaging system may include a pulsed illumination source operative to emit radiation pulses in the SWIR band towards a target resulting in reflected radiation from the target; (b) an imaging receiver including a plurality of Ge PDs operative to detect the reflected SWIR radiation and a controller, operative to control activation of the receiver for an integration time during which the accumulated dark current noise does not exceed the time independent readout noise.

Systems and methods are provided for providing a passively switched light source. An integrated optical component includes a photonic material and a phase change material in direct contact with the photonic material. A light source provides light into the integrated optical component. The light interacts with the phase change material such that an index of refraction of the phase change material depends on the intensity of the light within the integrated optical component as to provide a passive change to a parameter of the integrated optical component.

A laser system, comprising: a laser cavity, a gain medium positioned within the laser cavity, a pump source optically coupled to the gain medium, an input minor positioned at a first end of the laser cavity, an output coupler positioned at a second end of the laser cavity, a first etalon positioned within the laser cavity, and a q-switching element positioned within the laser cavity, wherein the laser system is configured to provide a laser beam at a selected wavelength ranging of 1700 to 3000 nm with a tunable spectral range of at least 10 nm. A method for using the laser system e.g., for producing a pulsed laser beam is further disclosed.

In one aspect, a composition of matter includes: a plurality of particles in a thixotropic suspension to form an ink, where the plurality of particles are present in an amount of at least about 20 vol %, and the plurality of particles include: a first host medium material containing at least one of: one or more lasing species dopants; and one or more other dopant species; and a second host medium material containing at least one other dopant species. The composition of matter further includes a liquid phase present in an amount greater than 20 vol % and less than about 80 vol %, where the liquid phase comprises at least one of: at least one surfactant; at least one polar organic solvent; and at least one binder.

In one aspect, a composition of matter includes: a plurality of particles in a thixotropic suspension to form an ink, where the plurality of particles are present in an amount of at least about 20 vol %, and the plurality of particles include: a first host medium material containing at least one of: one or more lasing species dopants; and one or more other dopant species; and a second host medium material containing at least one other dopant species. The composition of matter further includes a liquid phase present in an amount greater than 20 vol % and less than about 80 vol %, where the liquid phase comprises at least one of: at least one surfactant; at least one polar organic solvent; and at least one binder.