Apparatuses and methods are disclosed for applying laser energy having desired pulse characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device positioned along the optical axis of the resonator.

A titanium-sapphire laser apparatus may include a continuous wave oscillation laser unit, an amplification oscillator, a pulsed laser unit, an error detector, an error controller, and an optical path length corrector. The amplification oscillator may include an optical resonator and a titanium-sapphire crystal that is provided in an optical path in the optical resonator. The error detector may be provided in an optical path of leak light of seed light from the optical resonator, and may detect an optical path length error between an optical path length in the optical resonator and a positive integer multiple of a wavelength of the seed light and output an optical path length error signal. The optical path length corrector may vary the optical path length in the optical resonator on a basis of a signal resulting from adding a correction value to the optical path error signal.

The present application is directed to a planar waveguide amplifier. The planar waveguide amplifier includes a substrate having an upper surface and a lower surface. The planar waveguide amplifier includes a core formed on an upper surface of the substrate. The core includes a channel configured to transmit light there through. The planar waveguide amplifier also includes an upper cladding layer formed above the core. The upper cladding layer includes a glass doped with rare earth material in an amount less than about 5% of the upper cladding layer. The application is also directed to a method of amplifying a signal.

A lidar system comprises a photodetector circuit and a signal processing circuit. The photodetector circuit comprises an array of pixels for sensing incident light. The signal processing circuit processes a signal representative of the sensed incident light to detect a reflection of a laser pulse from a target within a field of view. The signal processing circuit can comprise a plurality of matched filters that are tuned to different reflected pulse shapes for detecting pulse reflections within the incident light, and wherein the signal processing circuit applies the signal to the matched filters to determine an obliquity for the target based how the matched filters respond to the applied signal.

A multi-core optical amplifying fiber device includes a plurality of multi-core optical amplifying fibers including a plurality of core portions doped with amplification medium and a cladding portion formed at outer peripheries of the plurality of core portions; and a connection portion connecting the core portions of the plurality of multi-core optical amplifying fibers to one another. The connection portion connects the core portions to restrain deviation, between every connected core portions, of amplification gain for a total length of the core portions connected one another.

An optical arrangement has a light source, which emits a light beam along a first optical axis. A first reflector is provided, and a second reflector reflects light reflected by the first reflector. The first reflector has a transverse offset from the first optical axis to reflect light along a second optical axis which has a parallel offset of two times the transverse offset of the first optical axis. The second reflector reflects the light beam back to the first reflector along a third optical axis having a parallel offset with a fixed amount in a fixed transverse direction in relation to the second optical axis. The light beam is reflected by the first reflector along a fourth optical axis which has a parallel offset in relation to the first optical axis with a fixed amount counter to the fixed transverse direction.

An object information acquiring apparatus is used which includes a laser medium that oscillates laser light, an excitation source that excites the laser medium, a voltage accumulator that applies a voltage to the excitation source, a voltage supplier that supplies a voltage to the voltage accumulator, a voltage controller that limits a maximum supplied voltage from the voltage supplier, a receiver that receives a photoacoustic wave generated by an object irradiated with the laser light, and a constructor that acquires characteristic information relating to the object in use of the photoacoustic wave, wherein the voltage controller compares a measured voltage value obtained by implementing division of a supplied voltage from the voltage supplier with a reference voltage value defining the maximum supplied voltage.

A solid-state laser active medium comprising an optical gain material; a heat sink, wherein the heat sink is transparent, in particular over a wavelength range of 200 nm to 4000 nm, preferably with an absorption coefficient of <1 cm.sup.−1; the heat sink having a high thermal conductivity, in particular ≧149 W/(m*K); wherein the optical gain material and the heat sink exhibit a root-mean square, RMS, surface roughness of <1 nm; wherein the optical gain material is attached to the transparent heat sink by direct bonding.

A laser apparatus and a polycrystalline material are described. The apparatus includes the polycrystalline material which is configured to receive pumping light at a pump wavelength and to produce an optical gain for laser oscillation at a laser wavelength different from the pump wavelength. The polycrystalline material includes a ceramic material with a predetermined grain size. The polycrystalline material further includes a rare earth dopant with a predetermined concentration, wherein the predetermined grain size and the predetermined concentration cause the polycrystalline material to exhibit the optical gain at the laser wavelength.

The invention relates to a LASER amplification module for a solid-state laser system and method for manufacturing thereof. The present invention relates to a laser amplification module for a solid-state laser. More particularly, the present invention relates to the module amplifying laser beam capable to provide effective cooling of a heat sink bonded to a solid-state disk. The monolithic laser amplification module (1) comprises a solid-state disk (2); a monolithic composite (6) comprising a heat sink (3) and a reflecting coating (4) configured to at least partially reflect an incident beam (5) propagated in the solid-state disk (2) in a wavelength range λ from 200 nm-10 μm, wherein the reflecting coating (4) is deposited on surface of the heat sink by a deposition method, wherein the heat sink (3) has: transverse thermal conductivity at least 100 W/m*K, Young's modulus at least 100 GPa, preferably at least 300 GPa; and thickness of the heat sink at least 1 mm, preferably at least 2 mm; and wherein the solid-state disk and the monolithic composite have surfaces (61 and 21) having PV-flatness<210 nm and have a surface roughness RMS<2 nm; and wherein the surfaces (21 and 61) of the solid-state disk (2) and the monolithic composite (6) are directly and permanently bonded together.