The passively q-switched diode end-pumped solid-state laser is used the gain medium made of Er:Yb doped crystal and the Q-switch made of Co.sup.2+:MgAl.sub.2O.sub.4 crystal. The optical elements are optimally designed for the resonator to achieve pulse energy in a range 0.5 mJ<E<2mJ with the pulse width in a range of 4 ns-15 ns. The resonator is appropriate to use in laser rangefinders, target designator, and other products in military and civilian applications.

In one embodiment, a lidar system includes a light source configured to emit light at one or more wavelengths between 1200 nm and 1400 nm. The lidar system also includes a scanner configured to scan the emitted light across a field of regard of the lidar system and a receiver configured to detect a portion of the emitted light scattered by a target located a distance from the lidar system. The lidar system further includes a processor configured to determine the distance from the lidar system to the target based at least in part on a round-trip time for the portion of the emitted light to travel from the lidar system to the target and back to the lidar system.

An amplifier assembly may include a first heat sink plate that includes a first channel, a second heat sink plate that includes a second channel, and an amplifier rod disposed in the first channel and the second channel. The second heat sink plate may be connected with the first heat sink plate such that the first channel and the second channel align. The amplifier rod may be connected to the first heat sink plate and the second heat sink plate by a non-eutectic solder.

A Q switch is vibrated by applying a first voltage, and pulsed laser light is emitted by applying a second voltage to the Q switch at a point in time at which a preset delay time has passed from the start of emission of excitation light. Then, in this case, a time which is within a period, for which the vibration of the Q switch continues, and at which the intensity of the pulsed laser light periodically changing due to the vibration of the Q switch is maximized in a case where a point in time of application of the second voltage to the Q switch is changed is set as the delay time.

A laser system may include a seed laser formed from a Ti:Sapphire laser providing pulsed light and an optical parametric amplifier to generate pulsed light within a Holmium emission spectrum as seed pulses in response to the pulsed light from the Ti:Sapphire laser. A laser system may further include an amplifier to generate amplified pulses of light in response to the seed pulses from the seed laser, where the amplified pulses include at least some of the seed pulses amplified by the one or more Holmium-doped gain media pumped by the one or more pump lasers. The amplifier may include one or more Holmium-doped gain media and one or more pump lasers providing continuous-wave pump light within an absorption spectrum of the one or more Holmium-doped gain media.

Provided is a single-crystal fiber including a waveguide structure for a wavelength to be subjected to optical amplification, in which at least one end of the single-crystal fiber is planar, an angle θ between a normal to a facet of the single-crystal fiber and an optical axis of the single-crystal fiber satisfies a relationship of θ=90°−tan.sup.−1(n.sub.2/n.sub.1), where n.sub.1 represents a refractive index of a medium of a space that uses the single-crystal fiber, and n.sub.2 represents a refractive index of the single-crystal fiber for a guided light beam having a polarization direction parallel with a plane that includes the normal to the facet and the optical axis, and a diameter Dx in an X-direction and a diameter Dy in a Y-direction of a cross-section of the single-crystal fiber perpendicular to the optical axis satisfies a relationship of (n.sub.2/n.sub.1)0.9≤Dx/Dy≤(n.sub.2/n.sub.1)1.1.

Disclosed is a laser device including: a rod-shaped laser medium extending in a first direction; a first light source unit including a first base having a first notch through which the laser medium passes and a plurality of excitation light sources attached to the first base; and a holder supporting the laser medium and the first light source unit. At least one of the first base and the holder includes a first regulating part configured to regulate a position of the first base with respect to the holder.

Disclosed is a laser device includes: a rod-shaped laser medium extending in a first direction; a first light source unit including a first base and a plurality of excitation light sources; a second light source unit arranged side by side with the first light source unit in a second direction intersecting with the first direction, the second light source unit including a second base and a plurality of excitation light sources; and a holder supporting the laser medium, the first light source unit, and the second light source unit. At least one of the first base and the holder includes a first regulating part configured to regulate a position of the first base with respect to the holder, and at least one of the second base and the holder includes a second regulating part configured to regulate a position of the second base with respect to the holder.

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.

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.