Abstract: A light emitting element includes: a substrate; a mesa portion formed on the substrate and including an active layer, a first semiconductor layer, and a second semiconductor layer; a metal layer including a first metal part disposed on a top surface of the mesa portion and connected to the second semiconductor layer and a second metal part formed integrally with the first metal part and extending along a side surface of the mesa portion; an insulating layer formed on the side surface; and a resin layer formed on the insulating layer. The first metal part includes an opening region formed with a light passage opening and a connection region for external connection. The second metal part is formed on the side surface via the insulating layer and the resin layer and overlaps the active layer when viewed in a direction perpendicular to a thickness direction of the substrate.

Abstract: A radio-frequency excited carbon dioxide (CO2) or carbon monoxide (CO) gas laser includes two electrodes, which have passivated surfaces, within a sealed housing. Features in a ceramic slab or a ceramic cylinder located between the electrodes define a gain volume. Surfaces of the ceramic slab or the ceramic cylinder are separated from the passivated surfaces of the electrodes by small gaps to prevent abrasion thereof. Reducing compressive forces that secure these components within the housing further reduces abrasion, thereby extending the operational lifetime of the gas laser.

Abstract: A broadband light source apparatus, and corresponding method, includes a broadband light source configured to provide broadband source light characterized by a source wavelength spectrum. The apparatus also includes a broadband optical filter including both a polarization changer with a length, as well as an exit polarizer. The broadband optical filter receives the source light and delivers broadband output light characterized by an output wavelength spectrum that is a function of the source wavelength spectrum and the polarization changer length and has an output centroid wavelength. The polarization changer length is configured to minimize a thermal sensitivity of the output centroid wavelength. The filter can be configured in view of a particular source wavelength spectrum to thermally stabilize the centroid wavelength and to maximize relative integrated output power passively with respect to ambient temperature fluctuations.

Abstract: Provided are a hybrid photon device including an etch stop layer and a method of manufacturing the hybrid photon device. The hybrid photon device includes: a silicon substrate including a waveguide on a surface thereof; a front etch stop layer and a rear etch stop layer disposed on a surface of the waveguide, the front and rear etch stop layers formed respectively to either side of the first region in a length direction of the waveguide; and a group III/V light-emitting unit generating light on a region of the silicon substrate between the front and rear etch stop layers.

Abstract: The disclosure relates to method and apparatus for micro-contact printing of micro-electromechanical systems (“MEMS”) in a solvent-free environment. The disclosed embodiments enable forming a composite membrane over a parylene layer and transferring the composite structure to a receiving structure to form one or more microcavities covered by the composite membrane. The parylene film may have a thickness in the range of about 100 nm-2 microns; 100 nm-1 micron, 200-300 nm, 300-500 nm, 500 nm to 1 micron and 1-30 microns. Next, one or more secondary layers are formed over the parylene to create a composite membrane. The composite membrane may have a thickness of about 100 nm to 700 nm to several microns. The composite membrane's deflection in response to external forces can be measured to provide a contact-less detector. Conversely, the composite membrane may be actuated using an external bias to cause deflection commensurate with the applied bias.

Abstract: A therapeutic laser with a source of pulsed electromagnetic radiation, a control device for controlling the intensity and/or the duration of the therapeutic laser applied to the tissue, and a detection device for detecting optoacoustic signals triggered by irradiating the living tissue with the pulsed electromagnetic radiation. The therapeutic laser is characterized by an evaluation device that acts on the control device and is used for calculating a degree of quality B(t) from the optoacoustic signals detected by the detection device for individual laser pulses applied to a predetermined laser spot and determining a fit function f(t) at a predetermined point in time ?t1, the fit function f(t) approximating the mean curve of B(t) for 0?t??t1. The intensity and/or the irradiation time of the therapeutic laser is defined by the parameters for the predetermined laser spot, the parameters being determined for the fit function f(t).

Abstract: The present invention provides a laser processing method comprising the steps of attaching a protective tape 25 to a front face 3 of a wafer 1a, irradiating a substrate 15 with laser light L while employing a rear face of the wafer 1a as a laser light entrance surface and locating a light-converging point P within the substrate 15 so as to form a molten processed region 13 due to multiphoton absorption, causing the molten processed region 13 to form a cutting start region 8 inside by a predetermined distance from the laser light entrance surface along a line 5 along which the object is intended to be cut in the wafer 1a, attaching an expandable tape 23 to the rear face 21 of the wafer 1a, and expanding the expandable tape 23 so as to separate a plurality of chip parts 24 produced upon cutting the wafer 1a from the cutting start region 8 acting as a start point from each other.

Abstract: A hybrid laser for generating radiation includes an optical passive material and an optical active material. The laser includes a first optical waveguide and optical laser components with reflectors in the optical passive material. The first optical waveguide is adapted for coupling out radiation from the hybrid laser. The laser also includes a second optical waveguide defined in the optical active material. The optical laser components include reflectors defining a cavity and furthermore are adapted for providing laser cavity confinement in the first optical waveguide and the second optical waveguide. The second optical waveguide thereby is positioned at least partly over the first optical waveguide so that an evanescent coupling interface is defined between the second optical waveguide and the first optical waveguide and the evanescent coupling interface is positioned within the laser cavity.

Abstract: An infrared laser source system that combines laser emitters through an optical waveguide. Each emitter is coupled to a port of the optical waveguide and the waveguided signal is combined to provide a spatially combined laser source with a single common exit aperture. The materials used for waveguiding allow the propagation of wavelengths in the infrared. The system can be used for combining multiple laser emitters to increase the total output power and/or for combination of multiple emitters with different wavelength for increased spectral coverage out of the laser system.

Abstract: High-efficiency method and device, to produce coherent Smith-Purcell radiation. A conductive diffraction grating, delimited by two conductive walls, is used, and an electron beam is passed above the grating to generate the radiation. According to the invention, the speed of the electrons is sufficiently low in order that, in a diagram (wave number k, frequency f), the beam line (I) intersects a portion (V) of a branch of the dispersion relationship, located in the first Brillouin zone, and corresponding to the grating's fundamental mode, at a point (P) located outside the zone delimited by the light lines (III, IV), and the current density of the beam is sufficiently high to excite the grating's fundamental mode which is radiated towards the outside thereof.

Abstract: Disclosed is a method for creating a mark desired properties on an anodized specimen and the mark itself. The method includes providing a laser marking system having a controllable laser pulse parameters, determining the laser pulse parameters associated with the desired properties and directing the laser marking system to mark the article using the selected laser pulse parameters. Laser marks so made have optical density that ranges from transparent to opaque, white color, texture indistinguishable from the surrounding article and durable, substantially intact anodization. The anodization may also be dyed and optionally bleached to create other colors.

Abstract: The invention is a method and apparatus for creating marks on an anodized aluminum specimen with selectable color and optical density. The method includes providing a laser marking system having a laser, laser optics and a controller operatively connected to said laser to control laser pulse parameters. The laser marking system is directed to produce laser pulses having laser pulse parameters associated with the desired color and optical density in the presence of a fluid directed to the surface of the anodized aluminum specimen while marking.

Abstract: Populations of Salmonella in animals may be substantially reduced by treatment with a vaccine composition which has been produced by exposing whole, intact cells of a Salmonella species to irradiation with an electron beam under conditions effective to kill the cells. The electron beam irradiated cells of Salmonella are effective for stimulating protective immune responses in the animals against the Salmonella. Induction of these immune responses significantly reduces or eliminates the colonization of the animal by the Salmonella, and consequently reduces or eliminates the shedding of Salmonella in the feces of the animals.

Abstract: A method of thermal forming of refractory alloy suture needles is disclosed. Needle blanks made from refractory alloys are used to form surgical needles, which are heated to a temperature above the ductile to brittle transition temperature but below the recrystallization temperature of the refractory alloy. The heated needle blanks are then mechanically formed into a surgical needle. A Fixture and an apparatus for forming refractory alloy surgical needles using this method are also disclosed.

Abstract: A projection system includes a light source module illuminating a plurality of monochromic lights, at least one optical modulator modulating the lights illuminated by the light source module according to each of color signals, a color combining prism combining the monochromic lights modulated by the optical modulator to form an image, and a projection lens projecting the image formed by the color combining prism toward a screen. A semiconductor diode including a P type semiconductor layer, an intrinsic semiconductor layer, and an N type semiconductor layer to absorb or transmit the monochromic lights according to the value of a reverse bias voltage is arranged in units of pixels.

Abstract: A light emitting diode (LED) structure, a LED packaging structure, and a method of forming LED structure are disclosed. The LED structure includes a sub-mount, a stacked structure, an electrode, an isolation layer and a conductive thin film layer. The sub-mount has a first surface and a second surface opposite the first surface. The stacked structure has a first semiconductor layer, an active layer and a second semiconductor layer that are laminated on the first surface. The electrode is disposed apart from the stacked structure on the first surface. The isolation layer is disposed on the first surface to surround the stacked structure as well as cover the lateral sides of the active layer. The conductive thin film layer connects the electrode to the stacked structure and covers the stacked structure.

Abstract: A method for controlling operation of a transistor includes the following steps: providing a bipolar transistor having emitter, base and collector regions; applying electrical signals to the transistor to produce light emission from the transistor; effecting photon-assisted tunneling of carriers in the transistor with self-generated photons of the light emission, and controlling operation of the transistor by controlling the photon-assisted tunneling.

Abstract: A method for producing an optical output, including the following steps: providing first and second electrical signals; providing a bipolar light-emitting transistor device that includes collector, base, and emitter regions; providing a collector electrode coupled with the collector region and an emitter electrode coupled with the emitter region, and coupling electrical potentials with respect to the collector and emitter electrodes; providing an optical coupling in optical communication with the base region; providing first and second base electrodes coupled with the base region; and coupling the first and second electrical signals with the first and second base electrodes, respectively, to produce an optical output emitted from the base region and coupled into the optical coupling, the optical output being a function of the first and second electrical signals.

Abstract: Provided is a super luminescent diode having low power consumption due to low threshold current and a high output power in low-current operation, which is suitable for an external cavity laser. The super luminescent diode for use in the external cavity laser is divided into a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region to provide a light source having a low threshold current and a nearly double output power of a conventional SLD.

Abstract: A 1.55 ?m SLD having a laser diode (LD) region and a semiconductor optical amplifier (SOA) region, and a method of fabricating the same, are disclosed. The SLD includes: an InP substrate having a LD region and a SOA region for amplifying light emitted from the LD region; an optical waveguide having a BRS (buried ridge strip) structure having an active layer of resonant strip pattern formed on the InP substrate and extending from the SOA region to the LD region; a first electrode formed on the active layer in the SOA region, a second electrode formed on the active layer in the LD region and electrically isolated from the first electrode; and a current blocking region interposed between the first electrode and the second electrode in order to electrically isolate the first electrode and the second electrode from each other.

Abstract: A blue phase liquid crystalline material comprising a mixture comprising at least one bimesogenic compound and at least one chiral compound, wherein the material is capable of stable existence in the blue phase over a temperature range of at least 5° C. A process for the preparation of the above blue phase liquid crystalline material, an optical device comprising it, a process of mirrorless lasing and a slotted monolithic optical waveguide using it are also disclosed.

Abstract: A method for the environment heat conversion in coherent electromagnetic energy by a super radiant quantum decay and a thermal excitation of a system of electrons is disclosed. A semiconductor device is also disclosed comprising a system of n-i-p-n transistors, a double array of quantum dots on the two sides of the thin i-layer of the n-i emitter, a system of intermediate n and p layers separating the active quantum region from the n and respectively p regions by potential barriers, a metal front electrode, a heat absorber in intimate contact with this electrode, a semitransparent rear electrode forming with the front electrode a Fabry-Perot resonator tuned with the electron quantum transition frequency through the i-layer, and an output semitransparent mirror of the same transparency as the transparency of the rear electrode, by this forming with the rear electrode a total transmission Fabry-Perot resonator.

Abstract: A light emitting device includes a substrate, at least one semiconductor light emitting device formed in or on the substrate, and upconverting material disposed in or on the substrate. The upconverting material is disposed in a path of light processed or emitted by the semiconductor device. The upconverting material absorbs light emitted by the semiconductor device and emits upconverted light in response. Integrated pixelated displays include a plurality of pixels formed on a surface of the substrate, with each pixel including up-conversion material based red light source, a blue light source a green light source, and a structure for selectively controlling emission from the red, blue and green lights sources for each of the pixels.

Abstract: A process including: magnetically energizing susceptible magnetic particles; and accumulating the resulting terahertz lasing mode output of the particles.

Abstract: Superradiance is generated by generating coherent radiation in the 10 gigahertz (1010) to terahertz (1012) regions of the electromagnetic spectrum. The radiation is produced by pulsing a micro crystal of a molecular magnet in a cavity or between a pair of superconductor mirrors at Kelvin or milli-Kelvin temperatures. The coherence and source of the radiation result from enhanced quantum mechanical spin tunneling. Alternatively, the radiation may be obtained by moving the crystal in and out of the field of a permanent magnet.

Abstract: A dual wavelength optical fiber distributed feedback laser comprises a pump laser coupled to a birefringent fiber in which a first grating device (two co-located single phase-shift fiber Bragg gratings (FBGs)) is provided. The grating device gives the laser two potential lasing modes in each of two orthogonal polarization states. A polarization mode coupling FBG selects two orthogonally polarized modes on which the laser oscillates. In a photonic data carrying signal source, the laser is coupled to a polarization dependent, optical modulator operable to apply a modulation, at a data signal frequency, to one polarization mode of the laser output. In an optical waveguide based electronic signal transmission system the modulated and un-modulated polarization modes output from the source are transmitted across a fiber transmission line to a polarizing optical fiber in which the two modes heterodyne to generate an electronic carrier signal in the optical domain.

Abstract: The present invention provides a laser machining apparatus in a simple structure which can properly carry out laser machining by irradiating a laser beam easily at a predetermined energy density to a machining-target site in a predetermined range, and in addition, which can be downsized and can be kept with easy maintenance and has enhanced durability. The apparatus includes: a semiconductor stack 1 comprising a plurality of semiconductor laser elements; and a controller for controlling emission of the laser beam emitted from each of the semiconductor laser elements. The semiconductor stack 1 is divided into a plurality of blocks B11, B12, B13, B14 in correspondence with the machining-target site of a work piece. The controller controls the irradiation of the laser beam from each of the blocks B11, B12, B13, B14 to be changeable in terms of time.

Abstract: High-efficiency laser-like emission at low thresholds in dipolar organic materials upon pulsed optical excitation, without using any external mirrors. Unusually high conversion efficiencies and low thresholds in laser-like emission have been observed in the solutions of organic molecular salts having large dipole moments and specific dye molecules having high photoluminescence efficiencies. Pumped with frequency-doubled pulses from a Nd:YAG laser, conversion efficiencies in the range of 15-40% were achieved without incorporation of external mirrors. The threshold pump energies for such emission have been observed to be low (<8 ?J). The spectrally narrowed output beam was found to have low divergence, high degree of polarization, and pulse-width less than that of the excitation pulses (50 picoseconds).

Abstract: Superradiance is generated by generating coherent radiation in the 10 gigahertz (1010) to terahertz (1012) regions of the electromagnetic spectrum. The radiation is produced by pulsing a micro crystal of a molecular magnet in a cavity or between a pair of superconductor mirrors at Kelvin or milli-Kelvin temperatures. The coherence and source of the radiation result from enhanced quantum mechanical spin tunneling. Alternatively, the radiation may be obtained by moving the crystal in and out of the field of a permanent magnet.

Abstract: An external-resonator laser system having multiple laser elements is configured to permit each laser to undergo individual amplification notwithstanding optical beam combination. In this way, overall output power may be scaled in a desired fashion, depending on the selected characteristics of the optical amplifier elements. To achieve additional power, each of the amplifiers may implemented as a phased array. Viewed more generally, a phased-array configuration affords beam combining in two stages, with each contributing input source itself composed of multiple sources whose outputs have been combined. If each phased-array source emits at a different wavelength, this design offers a multi-wavelength output whose power level may be scaled in accordance with the number and character of the devices forming each phased array.

Abstract: The negative effects of kinking in the L-I characteristics of laser diode operation with respect to feedback control for laser diode current control is suppressed by either (1) combining the output of a plurality of laser diodes together or (2) by imparting a current modulation superimposed on the direct driving current of the laser diode in conjunction with a limited feedback bandwidth, or a combination of both approaches (1) and (2).

Abstract: An illuminable laser sight has a power source, a laser module coupled to the power source, a laser module coupled to the power source and having a laser diode for emitting laser beams, and an adjuster module positioned around the laser module and coupled to the power source, the adjuster module having a front face and a laser light exit formed at the center of the front face and aligned with the laser diode. The laser sight further includes an illuminator module positioned adjacent the front face of the adjuster module, the illuminator module having a plurality of LEDs arranged in an annular manner to define a central bore that is axially aligned with the laser light exit and the laser diode.

Abstract: Disclosed is a gas laser utilizing radio frequency excitation in the area of sonic or supersonic/subsonic transfer gas flow. The laser uses various types of gases and mixtures of gases as the active medium using radio frequency excitation. The gas is supplied into a supersonic nozzle for acceleration of the active gaseous flow to supersonic or deceleration to high subsonic speeds in order to provide intensive dynamic cooling of the active gas medium. The gas is excited using radio frequency excitation in the critical area of the supersonic nozzle or downstream therefrom. The radio frequency action and excitation can also occur within the optical resonator region which is located within the supersonic area of the nozzle.

Abstract: An illuminable laser sight has a power source, a laser module coupled to the power source, a laser module coupled to the power source and having a laser diode for emitting laser beams, and an adjuster module positioned around the laser module and coupled to the power source, the adjuster module having a front face and a laser light exit formed at the center of the front face and aligned with the laser diode. The laser sight further includes an illuminator module positioned adjacent the front face of the adjuster module, the illuminator module having a plurality of LEDs arranged in an annular manner to define a central bore that is axially aligned with the laser light exit and the laser diode.

Abstract: Fiber-amplified spontaneous emission sources incorporating spectral filters show an improvement in mean wavelength stability versus a number of operating factors, including pump wavelength, pump power, feedback, and temperature. By adjusting the spectral characteristics of the filter, the position of the filter along the length of the fiber, and the length of the rare-earth doped fiber, a stable ASE source is designed so as to provide stable operating points for the mean wavelength versus desired operating parameters. In many cases the sources show an improvement in mean wavelength stability by an order of magnitude or more over present sources.

Abstract: An improved broadband light source for a Sagnac interferometer includes a waveguide, such as a fluorescent optical fiber, that is pumped by a pump source with a sufficient intensity to generate temporally incoherent light. The fluorescent optical fiber has first and second ends, one end being an input end of the fiber. The broadband light is provided at an output of the fluorescent optical fiber and is input to the interferometer. In order to prevent laser oscillations between the light source and the interferometer, one end of the fluorescent optical fiber is formed so as to prevent reflections. The light output from the fluorescent fiber to the interferometer comprises only that light that initially propagates toward the output of the optical fiber. In one embodiment of the light source, the pump light from the pump source is coupled into the fluorescent optical fiber in a direction so that it travels away from the output of the fluorescent optical fiber towards the first end.

Abstract: An improved broadband light source for a Sagnac interferometer includes a fluorescent optical medium that is pumped by light from a pump source with a sufficient intensity to cause the fluorescent optical medium to generate temporally incoherent light by superfluorescence. In the preferred embodiment, the superfluorescent optical medium comprises an optical fiber which is backward pumped. The signal output from the interferometer loop is amplified by the optical gain of the superfluorescent fiber which acts as a light source and as an amplifier. In order to avoid gain modulation in the superflorescent fiber, the modulation frequency is selected so that the modulation gain depth is substantially reduced.

Abstract: Disclosed is an x-ray laser system comprising a laser containing generating means for emitting short wave length radiation, and means external to said laser for energizing said generating means, wherein when the laser is in an operative mode emitting radiation, the radiation has a transverse coherence length to width ratio of from about 0.05 to 1. Also disclosed is a method of adjusting the parameters of the laser to achieve the desired coherence length to laser width ratio.

Abstract: An energy generator (10) that converts matter in the form of a gas into an energy source. The generator functions by injecting a gas, such as hydrogen, into a confined chamber (12). The chamber includes an annular permanent magnet (30) and a rotating magnetic assembly (32) that includes a plurality of magnetic fins (36) that form a funnel shape. The combination of the magnets (30), (36) serves to accelerate and centrifugally confine and cause the gas molecules to collide with one another until they acquire sufficient energy to cause lasing.

Abstract: An operational X-ray laser (30) is provided that amplifies 3p-3s transition X-ray radiation along an approximately linear path. The X-ray laser (30) is driven by a high power optical laser. The driving line focused optical laser beam (32) illuminates a free-standing thin foil (34) that may be associated with a substrate (36) for improved structural integrity. This illumination produces a generally cylindrically shaped plasma having an essentially uniform electron density and temperature, that exists over a long period of time, and provides the X-ray laser gain medium. The X-ray laser (30) may be driven by more than one optical laser beam (32, 44). The X-ray laser (30) has been successfully demonstrated to function in a series of experimental tests.

Abstract: A lighting device is provided for emitting superradiant fluorescent light. First material layers are provided which emit predetermined electromagnetic waves of spontaneous emission when supplied with a predetermined energy (e.g. a pumping ray or beam). Second material layers, transparent to the electromagnetic wave, are stacked between the layers of the first material. To provide an improved light emission, the second material layers are arranged so that the interspaces l between the first material layers are smaller than c.multidot..tau..sub.R, where c is the velocity of said electromagnetic wave and .tau..sub.R is a time constant of the spontaneous emission.

Abstract: X-ray laser method and apparatus for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4-50 cm.sup.-1.

Abstract: A super-radiant light source having an output with a low temporal coherence well suited, for example, to optical inertial sensor applications, includes a single mode optical waveguide such as an optical fiber having its core doped with an active laser material, such as neodymium. Pump light is coupled into the optical fiber at an intensity sufficient to produce a significant amplification of the spontaneous emission. The reflectivity at the exit end of the fiber is low enough so that even with a high gain for the light in one traverse through the fiber, the fiber is operated well below threshold for laser oscillation. The resulting emission is of high intensity, but has a low temporal coherence. In one form, the pump light is coupled into one end of the fiber and a dichroic filter is interposed in the light path between the pump light and the optical fiber to pass pump light into the core and reflect the spontaneous emission of the active material back into the core and toward the output.