Abstract: A method for switching a wavelength of a tunable wavelength laser, which is provided with a temperature control device for an etalon and a wavelength detecting section for identifying a wavelength of the laser by a front/back ratio of the etalon, the wavelength of the laser being set in a target wavelength on the basis of a detection result of the wavelength detecting section, and the method comprises: driving the laser at a first wavelength; suppressing output of light of the laser in response to a command indicating an optical output at a second wavelength; starting control of the temperature control device towards a second etalon temperature corresponding to the second wavelength; and before the etalon reaches the second etalon temperature, detecting that the etalon reaches a temperature range corresponding to an allowable wavelength range corresponding to the second wavelength, and cancelling the suppression of light in response thereto.

Abstract: A laser system that allows transverse arrangement of laser emitters around a laser medium. The system includes a laser medium with a coolant source and electrical controls. A pump layer has a mounting surface, an opposite bottom surface and a center aperture through which the laser medium is inserted. Laser diode emitters are disposed on the mounting surface circumferentially around the laser medium. An intermediate layer has at least one radial channel in fluid communication with the coolant conduit. The intermediate layer is in contact with the bottom surface. A middle layer has micro-channels formed therethrough and a center aperture. The micro-channels are radially arranged around the center aperture and the middle layer is in contact with the intermediate layer. The coolant source is fluidly coupled to the micro-channels to allow coolant to be directed through the microchannels and the radial channel to impinge on the bottom surface.

Abstract: An edge emitting semiconductor laser includes a semiconductor body including a waveguide region, the waveguide region including first and second waveguide layers and an active layer arranged between the first and second waveguide layers, that generates laser radiation; the waveguide region is arranged between a first and second cladding layers disposed downstream of the waveguide region; a phase structure for selection of lateral modes of the laser radiation emitted by the active layer, wherein the phase structure includes at least one cutout extending from a top side of the semiconductor body into the second cladding layer; at least one first intermediate layer composed of a semiconductor material different from that of the second cladding layer embedded into the second cladding layer; and the cutout at least partly extends from the top side into the first intermediate layer; the second cladding layer contains a first partial layer adjoining the waveguide region.

Abstract: Provided is a method for manufacturing a silicon carbide semiconductor device capable of preventing an increase in a cost of manufacturing one chip while favorably maintaining forward characteristics of the semiconductor device including (a) inspecting the characteristics of the forward conduction of body diodes as element structures; (b) classifying the body diode and the body diode as either a first group suitable for forward conduction or a second group unsuitable for forward conduction on the basis of an inspection result; and (c) manufacturing a silicon carbide semiconductor MOSFET that requires forward conduction using the body diode classified into the first group or manufacturing a silicon carbide semiconductor MOSFET that does not need forward conduction using the body diode classified into the second group.

Abstract: The invention relates to a skin treatment device, a lamp for use in such a skin treatment device, and its use. The skin treatment device according to the invention uses a combination of tanning-effective and/or anti-acne effective amounts of blue light in the spectral range from 400-440 nm in addition to the UV-light known in the art. An important advantage is that a lower UV dose can be used, leading to lower health risks, while the exposure times can be kept within acceptable limits, without compromising the skin treatment result.

Abstract: A method for sweeping an electromagnetic radiation source (12) to produce single mode operation having an optimized side-mode suppression ratio over a continuous range of wavelengths within a prescribed temporal profile, the electromagnetic radiation source is configured to output electromagnetic radiation at a given wavelength based upon parameters. The method includes determining a set of parameter combinations that satisfy a condition for a desired set of wavelengths and a maximum side mode suppression ratio over the range of wavelengths. The set of parameter combinations define sub-paths for transitioning from one wavelength to another wavelength. Combinations of select sub-paths provide a multivariate path for transitioning over the range of wavelengths. The method also includes controlling the semiconductor laser to emit electromagnetic radiation over the range of wavelengths by traversing the multivariate path in a desired manner.

Abstract: A method of isolating a semiconductor fin from an underlying substrate including forming a masking layer around a base portion of the fin, forming spacers on a top portion of the fin above the masking layer, removing the masking layer to expose the base portion of the fin, and converting the base portion of the fin to an isolation region that electrically isolates the fin from the substrate. The base portion of the fin may be converted to an isolation region by oxidizing the base portion of the fin, using for example a thermal oxidation process. While converting the base portion of the fin to an isolation region, the spacers prevent the top portion of the fin from also being converted.

Abstract: A hand held, home use, device for treatment of skin, comprising: a housing exhibiting an opening therein and forming an air cavity when the opening is placed in contact with the skin; an incandescent type bulb secured within the housing and arranged to irradiate the skin with infra-red radiation and heat air within the formed air cavity, the incandescent type bulb exhibiting a filament; and a control and driving circuitry in electrical communication with the incandescent type bulb and operative to output a train of pulses exhibiting an on time when current is driven through the filament and an off time when current is not driven through the filament, the off time greater than or equal to the on time, the off time being of a duration such that the infra-red radiation irradiating the skin falls, during the off time, to no less than 25% of its maximum value.

Abstract: In a method of stabilizing pump energy, a gain medium is provided having an absorption coefficient that varies with wavelength. An absorption coefficient curve of the absorption coefficient or a range of wavelengths comprises peaks and valleys. Pump energy is generated at an operating wavelength within one of the valleys, at which the absorption coefficient is approximately at a minimum. The pump energy is transmitted through the gain medium. A portion of the pump energy is absorbed with the gain medium and laser light is emitted from the gain medium responsive to the absorbed pump energy. The non-absorbed pump energy (feedback pump energy) is fed back to the pump module. The operating wavelength of the pump energy is stabilized using the feedback pump energy.

Abstract: A broadband, integrated quantum cascade laser is disclosed, comprising ridge waveguide quantum cascade lasers formed by applying standard semiconductor process techniques to a monolithic structure of alternating layers of claddings and active region layers. The resulting ridge waveguide quantum cascade lasers may be individually controlled by independent voltage potentials, resulting in control of the overall spectrum of the integrated quantum cascade laser source. Other embodiments are described and claimed.

Abstract: The wavelength of fundamental wave light emitted from a semiconductor laser is converted by a wavelength conversion element, and the wavelength-converted light is emitted. A power supply circuit feeds electric power to the semiconductor laser. A control part controls an amount of electric power to be fed to a heater such that the wavelength conversion element becomes a temperature that optimizes the wavelength conversion efficiency. Temperatures detected by an element temperature detector and a light source part temperature detector are introduced to the control part, and the control part takes a wavelength conversion element temperature, at which a temperature detected by the light source part temperature detector is minimum, as a set temperature that makes the wavelength conversion efficiency optimal, and feedback-controls the wavelength conversion element temperature such that the wavelength conversion element temperature is at the set temperature by controlling the heating quantity of the heater.

Abstract: A quantum cascade laser includes a substrate having first, second, third, and fourth regions; a stacked semiconductor layer including n-type lower and upper conductive layers, a core layer having a mesa structure, and a cladding layer; first and second buried layers disposed on side surfaces of the core layer and above the substrate; a first electrode disposed on the upper conductive layer above the first region; and a second electrode disposed on the lower conductive layer above the fourth region. The core layer is disposed on the lower conductive layer above the second region. The upper conductive layer is disposed on the first buried layer and the core layer. The cladding layer is disposed on the upper conductive layer above the second region. The substrate and the cladding layer are formed of an undoped or semi-insulating semiconductor. The first and second buried layers are formed of a semi-insulating semiconductor.

Abstract: A vertical-cavity surface-emitting laser diode includes: a first resonator that has a plurality of semiconductor layers comprising a first current narrowing structure having a first conductive region and a first non-conductor region; a first electrode that supplies electric power to drive the first resonator; a second resonator that has a plurality of semiconductor layers comprising a second current narrowing structure having a second conductive region and a second non-conductive region and that is formed side by side with the first resonator, the second current narrowing structure being formed in same current narrowing layer as the layer where the first current narrowing structure is formed; and a coupling portion as defined herein; and an equivalent refractive index of the coupling portion is smaller than an equivalent refractive index of each of the first resonator and the second resonator.

Abstract: It is the object of the present invention to specify a light source with high efficiency and high eye safety at the same time. For this purpose, the active layer (10), the first cladding layer (14), the first waveguide layer (12), the second waveguide layer (16), and the second cladding layer (18) should be designed such that 0.01 ?m?dwL?1.0 ?m and ?n?0.04, where dwL is the sum total of the layer thickness of the first waveguide layer (12), the layer thickness of the active layer (10), and the layer thickness of the second waveguide layer (16) and ?n is a maximum of the refractive index difference between the first cladding layer (14) and the first waveguide layer (12) and the refractive index difference between the second waveguide layer (16) and the second cladding layer (18).

Abstract: A plasmonic laser device has resonant nanocavities filled with a gain medium containing an organic dye. The resonant plasmon frequencies of the nanocavities are tuned to align with both the absorption and emission spectra of the dye. Variables in the system include the nature of the dye and the wavelength of its absorption and emission, the wavelength of the pumping radiation, and the resonance frequencies of the nanocavities. In addition the pumping frequency of the dye is selected to be close to the absorption maximum.

Abstract: A device is provided. The device includes a first organic light emitting device, which further comprises a first electrode, a second electrode, and an organic emissive layer disposed between the first electrode and the second electrode. The device also includes a first laser device, which further comprises an optical cavity and an organic lasing material disposed within the optical cavity. A focus mechanism is disposed to focus light emitted by the first organic light emitting device onto the first laser device. Preferably, the focus mechanism provides light incident on the first laser device at least 10 times greater, and more preferably at least 100 times greater, in intensity than the light emitted by the first organic light emitting device.

Abstract: A frequency tuneable or chirped laser device is described that includes a laser cavity formed from a plurality of optical components. The optical components include a laser source for generating a beam of light, a spectral tuning element and one or more further optical components for directing the beam of light on to the spectral tuning element. At least one of the plurality of optical components is moveable in a first degree of freedom; such movement simultaneously altering the effective optical path length of the laser cavity and the tuning frequency of the spectral tuning element. The effective optical path length and the tuning frequency of the device are substantially insensitive to any movement of said at least one moveable optical component in degrees of freedom other than the first degree of freedom. This provides frequency tuning in which mode hopping is suppressed.

Abstract: A method for operating a frequency converted laser source comprising at least one semiconductor laser and a wavelength conversion device optically coupled to at least one semiconductor laser may include operating the frequency converted laser source to produce a frequency converted output beam from the wavelength conversion device and intermittently heating the wavelength conversion device above a recovery threshold temperature TR of the wavelength conversion device. When the wavelength conversion device is heated above the recovery threshold temperature, the wavelength conversion device is held above the recovery threshold temperature TR for a period of time sufficient to restore output power lost to photo-degradation in the wavelength conversion device during operation of the frequency converted laser source.

Abstract: A laser device including lasing materials composed of nanoparticles in an aerosol phase. One example is Nd2O3 in DMDCS with DMSO which is sprayed into a cuvette, measures have to be taken to prevent for aggregation. The fluorescence life-time is significantly shorter compared to nanoparticles dissolved in a liquid.

Abstract: A laser system comprising a laser configured to generate a laser beam, a power supply arranged to provide a drive power to the laser, a photodetector arranged to detect the power of the laser beam and provide a detection signal from the power of the laser beam and a feedback loop arranged to form a feedback signal by subtracting a target signal from the detection signal wherein the feedback signal has a high bandwidth, amplify the feedback signal and adjust the drive power according to the amplified feedback signal, thereby reducing noise in the laser beam.