Abstract: The present invention relates to a laser device being formed of at least one VCSEL (15) with intracavity contacts. The VCSEL comprises a layer structure (18) with an active region (6) between a first DBR (4) and a second DBR (10), a first current-injection layer (5) of a first conductivity type between the first DBR (4) and the active region (6), and a second current-injection layer (8) of a second conductivity type between the second DBR (10) and the active region (6). The first and second current-injection layers (5, 8) are in contact with a first and a second metallic contact (11, 12), respectively. The first and/or second DBR (4, 10) are formed of alternating Aluminum oxide and Al(x)Ga(1?x)As containing layers. The proposed design of this VCSEL allows an increased efficiency and lower production costs of such a laser since the top and bottom DBRs may be formed of a considerable reduced thickness.

Abstract: Embodiments are directed to systems and methods for correcting lateral and angular displacement of laser beams within a laser cavity. For some embodiments, such systems and methods are used to correct angular displacement of laser beams within a laser cavity that result from varying the lasing wavelength in a tunable laser system.

Abstract: An aluminium gallium indium phosphide (AlGaInP)-based semiconductor laser device is provided. On a main surface of a semiconductor substrate formed of n-type GaAs (gallium arsenide), from the bottom layer, an n-type buffer layer, an n-type cladding layer formed of an AlGaInP-based semiconductor containing silicon (Si) as a dopant, an active layer, a p-type cladding layer formed of an AlGaInP-based semiconductor containing magnesium (Mg) or zinc (Zn) as a dopant, an etching stopper layer, and a p-type contact layer are formed. Here, when an Al composition ratio x of the AlGaInP-based semiconductor is taken as a composition ratio of Al and Ga defined as (AlxGa1?x)0.5In0.5P, a composition of the n-type cladding layer is expressed as (AlxnGa1?xn)0.5In0.5P (0.9<xn<1) and a composition of the p-type cladding layer is expressed as (AlxpGa1?xp)0.5In0.5P (0.9<xp?1), and xn and xp satisfy a relationship of xn<xp.

Abstract: An optical pumping structure for lasers includes: an active medium in the form of a cylindrical rod with a circular cross-section, said rod being inserted at its ends into two rings made of a thermally conductive material; at least three stacks of pumping diode strips arranged in the form of a star around the rod; and a support temperature-regulated by a Peltier-effect module. The rings are in contact with the support, and a stack of diodes, called bottom stack, being situated between the rod and the support, and the structure comprises, for each other stack, a thermal conduction block forming a support for said stack, these blocks being mounted on the cooled support and not being in contact with one another or with the rings.

Abstract: The patent refers to one or more droplets of chiral liquid crystals used as point source(s) of laser light. The source is shaped as a droplet of chiral liquid crystals (1) and an active medium preferably dispersed in the liquid crystals. The source is spherical and with a size of preferably between a few nanometres and 100 micrometres. A droplet consists of chiral liquid crystals (1) that have selective reflection in the range of the active medium's emission and can be cholesteric liquid crystals, a mixture of nematic liquid crystals and a chiral dopant or any other chiral liquid-crystal phase, preferably the blue phase, the ferroelectric phase, the antiferroelectric phase, any of the ferrielectric phases or another chiral phase of a soft substance, that need not be chiral by itself.

Abstract: A method and apparatus for producing single mode random fiber ring laser by inducing random distributed feedback in a short section of the fiber ring to thereby enable single mode lasing while reducing frequency jitter and relative intensity noise. The random distributed feedback maybe achieved through deep refractive index modulation at a series of randomly distributed laser-irradiated points inscribed along the length of the induced random distributed feedback fiber. The laser-processed random distributed feedback fiber maybe incorporated into the fiber ring in conjunction with a variable optical attenuator and band pass optical filter for enhancing the single mode operation.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: An economical slab laser for high power applications. The laser is a lamp driven slab design with face-to-face beam propagation and an end reflection that redirects the amplified radiation back out the input surface. Also presented is a side-to-side larger amplifier configuration, permitting very high average and peak powers due to the electrical efficiency of converting and getting energy into the crystal, optical extraction efficiency, and scalability of device architecture. Cavity filters adjacent to pump lamps convert the unusable UV portion of the pump lamp spectrum into light in the absorption band of the slab laser thereby increasing the overall pump efficiency. The angle of the end reflecting surface is changed to cause the exit beam to be at a different angle than the inlet beam, thereby eliminating the need to separate the beams external to the laser with the subsequent loss of power.

Abstract: A laser includes an optically pumped semiconductor OPS gain-structure. The apparatus has a laser-resonator which includes a mode-locking device for causing the laser to deliver mode-locked pulses. The resonator has a total length selected such that the mode-locked pulses are delivered at a pulse repetition frequency less than 150 MHz. An optical arrangement within the resonator provides that radiation circulating in the resonator makes a plurality of incidences on the OPS gain-structure with a time less than the excited-state lifetime of the gain-structure between successive incidences.

Abstract: An optical amplifier includes a solid state gain-element. The gain-element is pumped by pump-radiation from a diode-laser bar. The diode-laser radiation is delivered from the diode-laser bar to the gain-element entirely via a tapered light-guide which guides the radiation only in a fast-axis direction of the diode laser bar. The tapering of the light-guide reduces fast-axis divergence of the pump-radiation by about a factor of ten. The pump-radiation is delivered to the gain-element as a line of radiation homogenized in the fast-axis direction.

Abstract: The different advantageous embodiments provide an apparatus and method comprising a substrate configured to increase an intensity of light at a desired wavelength. The substrate has a front side, a back side, and an outer edge. The substrate is configured to reflect the light received on the front side of the substrate. The substrate comprises ceramic. The substrate comprises a plurality of sections. The method and apparatus also comprise a material configured to attenuate the light passing between the plurality of sections. The material surrounds an edge of each section of the plurality of sections. The apparatus and method also comprise a cooling system configured to allow liquid nitrogen to be transmitted through the cooling system and receive heat generated in the substrate from the back side of the substrate.

Abstract: Embodiments of systems and methods are provided for a tunable laser device. The tunable laser device may include a diffraction grating connected to a pivot arm that pivots the diffraction grating about a pivot point to tune the laser device. In pivoting the diffraction grating about the pivot point, both the wavelength to which the diffraction grating is tuned and the length of the optical cavity may be changed. The length of the pivot arm may be selected to reduce the number of mode hops of the tunable laser device when tuning the laser device over its tuning range.

Abstract: A method is for operating a pump light source having a diode laser, which provides a pump light, in particular for optical pumping of a laser device. The pump light source is activated in a first mode of operation such that the diode laser assumes a predefinable target temperature, which lies in a range of a maximum of the coefficient of absorption of the laser-active solid of the laser device. In a second mode of operation, following the first mode of operation, the pump light source is activated such that it generates pump light to build up a population inversion in the laser-active solid of the laser device. In a third mode of operation, following the second mode of operation, the pump light source is activated such that it generates pump light to activate a laser operation in the laser device.

Abstract: An integrated circuit includes an optical source that provides an optical signal to an optical waveguide. In particular, the optical source may be implemented by fusion-bonding a III-V semiconductor to a semiconductor layer in the integrated circuit. In conjunction with surrounding mirrors (at least one of which is other than a distributed Bragg reflector), this structure may provide a cavity with suitable optical gain at a wavelength in the optical signal along a vertical direction that is perpendicular to a plane of the semiconductor layer. For example, the optical source may include a vertical-cavity surface-emitting laser (VCSEL). Moreover, the optical waveguide, defined in the semiconductor layer, may be separated from the optical source by a horizontal gap in the plane of the semiconductor layer. During operation of the optical source, the optical signal may be optically coupled across the gap from the optical source to the optical waveguide.

Abstract: Multi-mode diode emitters are stacked in a staircase formation to provide a spatially-multiplexed output. Improved coupling efficiency is achieved by providing tilted collimated output beams that determine an effective step height of the stepped structure. Since the effective step height is dependent on the tilt angle, a variable number of emitters can be used inside packages having a same physical step height, while still attaining high coupling efficiency.

Abstract: A method for quasi-synchronous tuning of wavelength or frequency of grating external-cavity semiconductor laser and a corresponding semiconductor laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) as rotation center, so as to achieve the frequency selections by grating and resonance cavity in quasi-synchronous tuning, wherein the angle of the line between the quasi-synchronous tuning point (Pq) and a conventional synchronous tuning point (P0) with respect to the direction of light incident on the grating is determined according to the angle difference between the incidence angle and diffraction angle of light on the grating. According to present invention, approximately synchronous tuning of laser is achieved with a simple and flexible design.

Abstract: A laser diode device includes a laminated structure in which a first compound semiconductor layer, a third compound semiconductor layer that has a light emitting region and a saturable absorption region, and a second compound semiconductor layer are sequentially layered, a second electrode, and a first electrode. The laminated structure has ridge stripe structure. The second electrode is separated into a first section to obtain forward bias state by applying a direct current to the first electrode through the light emitting region and a second section to add electric field to the saturable absorption region by an isolation trench. When minimum width of the ridge stripe structure is WMIN, and width of the ridge stripe structure of the second section of the second electrode in an interface between the second section of the second electrode and the isolation trench is W2, 1<W2/WMIN is satisfied.

Abstract: A power monitoring and correction to a desired power level of a laser or group of lasers utilizes two photodetectors which are employed to accurately determine the amount of output power from the front end or “customer” end of a laser or a plurality of such lasers. During power detection, which may be accomplished intermittently or continuously, the laser is modulated with a tone of low frequency modulation. One photodetector at the rear of the laser is employed to detect the DC value of the frequency tone, i.e., a value or number representative of the AC peak-to-peak swing, amplitude or modulation depth of the tone. Also, the rear photodetector may be employed to determine the optical modulation index (OMI). In either case, these values may be employed in a closed loop feedback system to adjust or otherwise calibrate the value of the low tone frequency relative to the total desired bias current applied to the laser.

Abstract: A method for quasi-synchronous tuning of wavelength or frequency of grating external-cavity semiconductor laser and a corresponding semiconductor laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) as rotation center, so as to achieve the frequency selections by grating and resonance cavity in quasi-synchronous tuning, wherein the angle of the line between the quasi-synchronous tuning point (Pq) and a conventional synchronous tuning point (P0) with respect to the direction of light incident on the grating is determined according to the angle difference between the incidence angle and diffraction angle of light on the grating. According to present invention, approximately synchronous tuning of laser is achieved with a simple and flexible design.

Abstract: Embodiments are directed to systems and methods for correcting lateral and angular displacement of laser beams within a laser cavity. For some embodiments, such systems and methods are used to correct angular displacement of laser beams within a laser cavity that result from varying the lasing wavelength in a tunable laser system.