119results about How to "Improve laser efficiency" patented technology

A semiconductor laser device has a semiconductor laser diode structure made of group III nitride semiconductors having major growth surfaces defined by nonpolar planes or semipolar planes. The semiconductor laser diode structure includes a p-type cladding layer and an n-type cladding layer, a p-type guide layer and an n-type guide layer held between the p-type cladding layer and the n-type cladding layer, and an active layer containing In held between the p-type guide layer and the n-type guide layer. The In compositions in the p-type guide layer and the n-type guide layer are increased as approaching the active layer respectively. Each of the p-type guide layer and the n-type guide layer may have a plurality of In_xGa_1-xN layers (0≦x≦1). In this case, the plurality of In_xGa_1-xN layers may be stacked in such order that the In compositions therein are increased as approaching the active layer.

A semiconductor light emitting device is made of a group III nitride semiconductor having a major growth surface defined by a nonpolar plane or a semipolar plane, and has a quantum well layer containing In in a light emitting layer. A strain compensation layer made of a group III nitride semiconductor containing Al and having a lattice constant smaller than the lattice constant of the quantum well layer in a strain-free state is interposed in the light emitting layer of a quantum well structure having the quantum well layer and a barrier layer or in an adjacent layer adjacent to the light emitting layer.

An apparatus for intraoral scanning includes an elongate handheld wand that has a probe. One or more light projectors and two or more cameras are disposed within the probe. The light projectors each has a pattern generating optical element, which may use diffraction or refraction to form a light pattern. Each camera may be configured to focus between 1 mm and 30 mm from a lens that is farthest from the camera sensor. Other applications are also described.

The present invention relates to granular composite density enhancement, and related methods and compositions. The applications where these properties are valuable include but are not limited to: 1) additive manufacturing (“3D printing”) involving metallic, ceramic, cermet, polymer, plastic, or other dry or solvent-suspended powders or gels, 2) concrete materials, 3) solid propellant materials, 4) cermet materials, 5) granular armors, 6) glass-metal and glass-plastic mixtures, and 7) ceramics comprising (or manufactured using) granular composites.

A vortex laser based on a laser medium center zero gain structure is applied to optical tweezers, optical spanners and the field of optical communication. The vortex laser comprises a pumping source, an optical coupling system, an input mirror, a zero gain center laser medium, and an output mirror, all of which are arranged in sequence. The zero gain center laser medium is a piece of ceramic or crystal which is provided with a hole in the center and annularly doped with activated ions or doped with zero-activated ions in the center region. Fundamental transverse mode oscillation is inhibited by the zero gain center structure of the laser medium. Pure higher-order Laguerre-Gaussian (LG0, l(l>=1)) beam output is realized through mode matching. No other optical components are needed, and no pumping spot shaping is needed. The vortex laser has the advantages of high laser efficiency, wide scope of applications, simple operation, easy integration, and the like.

The invention describes the method and apparatus for enhanced efficiency in a laterally-coupled distributed feedback (LC-DFB) laser. In a device featuring the effective ridge design, lateral confinement of the guided optical modes is provided by a surface etched grating, which also serves as a DFB element of the laser. Coupling and quantum efficiency of such a LC-DFB laser both improve with an increase of the lateral mode order. In accordance with this invention, a dramatic enhancement of the laser efficiency is achievable by designing it to operate in one of the higher order modes, notably the first order mode, while all the other lateral modes, including the zero order mode, are suppressed through gain-loss discrimination. In the exemplary embodiment of the invention, this enhanced efficiency technique is applied to the design of a single-mode LC-DFB laser suitable for a monolithic integration with other active and passive functional elements of photonic integrated circuits fabricated by using one-step epitaxial growth.

Particular embodiments of the present invention relate generally to semiconductor lasers and laser scanning systems and, more particularly, to schemes for controlling semiconductor lasers. According to one embodiment of the present invention, a laser is configured for optical emission of encoded data. At least one parameter of the optical emission is a function of a drive current I_GAIN injected into the gain section of the semiconductor laser and one or more additional drive currents I/V_PHASE, I/V_DBR. Mode selection in the semiconductor laser is altered by applying a phase shifting signal I/V_Φ to the phase section that is synched with a wavelength recovery portions in drive current I_GAIN such that a plurality of cavity modes are shifted by one half of the free spectral range at each wavelength recovery portion. In this manner, patterned variations in the wavelength or intensity profile of the laser can be disrupted to disguise patterned flaws that would otherwise be readily noticeable in the output of the laser.

The present invention is a laser irradiation apparatus which is capable of selecting among a plurality of laser lights L having different wavelengths a laser light of a wavelength according to a purpose of irradiation and irradiating an object Ob to be irradiated with the laser light having the wavelength. The laser irradiation apparatus includes: on an optical path of a mixed light beam of the plurality of laser lights L having different wavelengths, a slit having a width corresponding to a diffraction limit of the laser light having the shortest wavelength among the plurality of laser lights L having different wavelengths; and an objective lens for focusing a laser light that has passed through the slit, on the object Ob to be irradiated.

High-efficiency mid-infrared laser crystal is used for outputting mid-infrared laser with the wave band ranging from 2.7 micrometers to 3 micrometers. The molecular formula of the crystal is Cr2xEr3yRe3zY3(1-y-z)Sc2(1-x)Ga3O12, wherein the Er is the abbreviation for Er3+, the Re is the abbreviation for Re3+, the Y is the abbreviation of Y3+, the Cr is the abbreviation for Cr3+, the Re3+ is Eu3+ or Tb3+, both the Re3+ and the Er3+ substitute Y3+ ions in 3Sc2Ga3O12 host crystal, the substitution concentration of the Er3+ ranges from 5at% to 30at%, namely the y ranges from 0.05 to 0.3, the substitution concentration of the Re3+ ranges from 0.1at% to 5at%, namely, the z ranges from 0.001 to 0.05, and the substitution concentration of the Cr3+ ranges from 0.1at% to 5at%, namely, the x ranges from 0.001 to 0.05. ions of the Re3+(Re=Eu, Tb) have an energy level structure close to ions of the Er3+, the evaporation rate of particles with the energy level of 4I13/2 can be increased by the aid of resonance energy transfer among the ions of the Re3+ and the ions of the Er3+, the life time of the energy level of laser with the wave band ranging from 2.7 micrometers to 3 micrometers can be shortened to a certain degree, accordingly, output efficiency and power of laser of the crystal can be effectively enhanced, and the high-efficiency mid-infrared laser crystal has important application in the fields of bio-medical treatment, optical parameter oscillation, electro-optical countermeasure and the like.

The invention discloses an air-breathing premixed carbon dioxide pneumatic laser driven by continuous rotary detonation combustion. The laser comprises an air-breathing continuous rotary detonation combustion device, a transition section, a CO2 pneumatic laser generation device and an exhaust section. The air-breathing continuous rotary detonation combustion device is used for generating a high-temperature and high-pressure fuel gas heat source serving as total energy for downstream output laser, and comprises a center body and a cylindrical shell. The center body comprises an air inlet cone part, a large cylinder part, a small cylinder part and a tail cone part which are sequentially arranged from front to back. An air inlet channel is formed by a gap between the air inlet conical part and the front-end conical shell, and a rotary detonation combustion chamber is formed by a gap between the small cylindrical part and a rear-end cylindrical shell. The laser is applied to an air-breathing aircraft, and the air-breathing continuous rotary detonation combustion device is adopted as a pumping source; the generated laser is high in efficiency, and energy is saved. The same air-breathingcontinuous rotary detonation combustion device is adopted without increasing the load, so not only can thrust be generated, but also laser can be generated.

The invention relates to novel gadolinium gallium garnet laser crystal activated by 1.54mu m wave-band rare earth ion, which belongs to the field of laser crystal materials. The chemical formula of the laser crystal material is Yb: Er: Ce: Gd3Ga5O12. Super-fine powders of Ga2O3, Gd2O3, Er2O3, Yb2O3 and CeO2 serve as the raw material, and the Yb: Er: Ce: Gd3Ga5O12 raw material is obtained through a high-temperature solid phase reaction in reducing atmosphere like nitrogen; the crystal is grown through a pulling method in the reducing atmosphere like nitrogen. The material is used to output the 1.54mu m wave-band laser.

The invention discloses a high-efficiency holmium laser. The laser comprises a resonant cavity, a light condensation cavity, a laser crystal rod, and a pulse xenon lamp. The light condensation cavity comprises a ceramic reflector, a cerium-doped quartz socket tube, current guide baffle plates, crystal end heating sleeves, and a cavity structure. The cerium-doped quartz socket tube is embedded into the ceramic reflector, and the laser crystal rod passes through the cerium-doped quartz socket tube. Moreover, two ends of the laser crystal rod are supported by the cavity structure, thereby achieving the sealing of the interior and exterior of the cavity. The two crystal end heating sleeves respectively sleeve two ends of the laser crystal rod, and are fixed through the cavity structure. The pulse xenon lamp passes through the ceramic reflector, and two ends of the pulse xenon lamp are supported by the cavity structure, thereby achieving the sealing of the interior and exterior of the cavity. The current guide baffle plates with small holes are disposed at two ends of the ceramic reflector. The laser can achieve that laser crystal works under lower temperature, greatly improves the efficiency, prevents the moisture condensation on an end face of an optical device from causing sudden damage, and guarantees the long-time reliable operation.

The invention discloses a high-power LD (Laser Diode) pumping thulium laser module. The high-power LD pumping thulium laser module comprises a laser crystal bar, a quartz socket tube, an LD array, a light guiding structure and a crystal end part heating sleeve which are mounted in a stainless steel support structure, wherein the laser crystal bar is a Tm:YAG bonding crystal bar; the lengths of non-doped parts at two ends of the laser crystal bar are not less than 35mm; the lengths of doping parts are 60mm; the non-doped parts at the two ends of the laser crystal bar are sealed, positioned and mounted in crystal mounting holes; a water path for cooling the LD array is arranged inside a copper matrix of the light guiding structure; and a low-temperature cooling water path for cooling the Tm:YAG bonding crystal bar is also arranged in the support structure. According to the laser module, high-low-temperature cooling of an LD pumping source and a thulium laser crystal can be conveniently realized; the damage to the device caused by water vapor condensation due to low temperature of an end face of an optical device on the basis that the laser efficiency is increased is avoided; and meanwhile, a thermal lens effect is reduced and the long-time reliable operation is ensured.

A method for preparing yttrium aluminum garnet crystals doped with Yb3+ and Cr4+ ions. The raw materials of the method are formulated according to the following reaction equation: 3xYb2O3+3(1-x-z)Y2O3+5(1-y)Al2O3+5yCr2O3+ 6zCaCO3=2Yb3xY3(1-x-z) Cr5yCa3zAl5(1-y) O (12-3z/2) +6zCO2 in which 0.05≤x≤0.5, 0.01%≤y≤2%, y≤z≤5y, in common The medium frequency induction heating single crystal furnace adopts the pulling method to grow. The method of the invention is easy to grow the yttrium aluminum garnet crystal of Yb3+ and Cr4+ ions, and the crystal can be directly pumped by an InGaAs semiconductor laser to realize the excitation output of 1.1-1.6 μm, and can improve the laser performance of the crystal.

The invention relates to an intelligent power supply line maintenance system, comprising laser bird repellent equipment, a CCD (Charge Coupled Device) vision sensor, bird body detection equipment and a robot main body architecture, wherein the CCD vision sensor is used for acquiring a power supply line image; the bird body detection equipment is connected with the CCD vision sensor, and is used for recognizing a target bird body type in the power supply line image; the robot main body architecture is respectively connected with the laser bird repellent equipment and the bird body detection equipment, and is used for determining the wavelength of bird repellent laser emitted by the laser bird repellent equipment on the basis of the target bird body type. Through the intelligent power supply line maintenance system, flying birds on a power supply line can be intelligently and self-adaptively repelled.