133 results about "Microchip laser" patented technology

For increasing the power emitted by surface emitting lasers and for improving the spatial coherence of the laser beam, emitted in particular by disk lasers, microchip lasers and VCSELs having a relatively wide emitting area, the invention proposes to select a low order transverse cavity mode by means of a mirror structure (12) of high reflectivity, and of high angular selectivity. The mirror structure comprises a multilayer (14) receiving the optical beam (24) and a resonant grating mirror (16) following the multilayer and arranged for highly reflecting the optical beam in a narrow angular range at each side of a determined incidence angle.

A miniaturized laser package is provided comprising a standard semiconductor laser package modified to accept a solid state microchip assembly pumped by the diode laser. Standard packages described in the invention include TO and HHL packages all of which are characterized by small dimensions, well sealed housing, robust mounting features, known characterized materials and economical production and assembly techniques characteristic of the semiconductor processing industry. In particular, the microchip lasers are produced using high density techniques that lend themselves to mass production, resulting in very low unit costs. At the same time, the compact laser devices provide a solution to the problem of providing laser radiation at high beam quality and good reliability features with a variety of wavelengths and operational characteristics and low noise features not available from diode lasers yet relying primarily on standardized designs, materials and techniques common to diode laser manufacturing. The devices constructed according to methods taught by the invention can therefore be readily integrated into numerous applications where power, reliability and performance are at a premium but low cost is essential, eventually replacing diode lasers in many existing systems but also enabling many new commercial, biomedical, scientific and military systems.

The invention discloses a laser self-mixing multi-physical parameter measurement method and a laser self-mixing multi-physical parameter measurement device for an atmospheric particulate. The laser self-mixing multi-physical parameter measurement device comprises a microchip laser, a collimating lens, a beam splitter, converging lenses, a photodetector, an amplifier, a data acquisition card and a spectrum analyzer. Laser emitted by the microchip laser is focused onto the atmospheric particulate to be measured through the collimating lens and the converging lens, and part of generated backwards-scattered light is fed back to the laser due to the reversibility principle of an optical path, so that parameters such as power and wavelength of the laser are changed, namely a laser self-mixing effect is achieved. In addition, the beam splitter is additionally arranged in the optical path to split a small part of laser beam for the photodetector to receive, and a laser self-mixing signal is acquired and analyzed by the amplifier, the data acquisition card and the spectrum analyzer. The laser self-mixing multi-physical parameter measurement device has a simple structure, and is easy to regulate; and the detection accuracy of an atmospheric particulate detection device is effectively improved.

The invention relates to an electronic distance measuring device which measures the propagation time to and from a target of a shor pulse of a trasmitted electromagnetic beam from a radiation source comprising a microchip laser, and comprising objective optical system (6; 16; 21); for the reflected beam from the target and a detecting unit (9; 13; 20) to which the received beam is transmitted. Means (4, 5; 15) is provided for making the transmitted and the receiving electromagnetic beam coaxial. Means (6, 10, 12; 14, 16; 21, 22) are also provided for focusing the received beam onto the detecting unit (9; 13; 20). A means (3) makes the transmitted electromagnetic beam simultaneously as narrow and as collimated as possible in order to get a well-defined radiation measuring spot on the target.

A method for producing low-noise laser output at wavelengths ranging from IR through visible to UV in various operation modes from a monolithic microchip laser comprises schemes of (1) generating one or two fundamental beam(s) from light source(s) selected upon the desired wavelength(s), polarization(s), and other features related to the desired laser output; (2) intracavity beam combination / separation due to the walk-off effect in one or more birefringent crystal(s) transparent to the propagating lights and highly anisotropic; (3) wavelength conversion in one or more nonlinear optical crystal(s); (4) compact and efficient pump source(s); and (5) minimization of intracavity loss / noise. One resonator cavity supports only one fundamental beam, which eliminates the green problem. The gain media can be selected from an extensive group of materials including isotropic and naturally birefringent crystals, with polarization dependent or independent laser emissions. Laser devices constructed in accordance with the inventive method are demonstrated with various configurations.

A method for producing low-noise laser output at various wavelengths and / or in various operation modes in a monolithic microchip laser comprises schemes of generating two fundamental beams in separate cavities, precise intracavity beam combination based on the walk-off effect in birefringent crystal, and wavelength conversion in nonlinear optical crystals. The fundamental beams are produced from light sources selected upon the desired wavelengths, polarizations, and other features related to the laser output. Low-noise laser devices operated in SLM or with spectra of flat-top or desired bandwidths are constructed according to the method. High-volume fabrication is feasible. Apparatus of compact size and efficient frequency conversion is demonstrated with various configurations including those for generating low-noise 491 nm laser, as a replacement of Argon ion laser.

For increasing the power emitted by surface emitting lasers and for improving the spatial coherence of the laser beam, emitted in particular by disk lasers, microchip lasers and VCSELs having a relatively wide emitting area, the invention proposes to select a low order transverse cavity mode by means of a mirror structure (12) of high reflectivity, and of high angular selectivity. The mirror structure comprises a multilayer (14) receiving the optical beam (24) and a resonant grating mirror (16) following the multilayer and arranged for highly reflecting the optical beam in a narrow angular range at each side of a determined incidence angle.

Geometrical design of laser microchips is disclosed that allows variation of the optical path length in the different media by simple displacement of the microchip, the movement having a non-zero projection orthogonal to the pump beam. The concept can be implemented to vary optical loss in the lasing cavity, the absorbed pump power, or the optical length of the cavity. Passively Q-switched microchip laser output performance can thus be controlled by simple transverse displacement of the microchip relative to the pump beam. The above microlaser can be combined with voltage-controlled variable-focus output optics in order to control the peak power density of the laser pulses.

A method for producing low-noise laser output at various wavelengths and / or in various operation modes in a monolithic microchip laser comprises schemes of generating two fundamental beams in separate cavities, precise intracavity beam combination based on the walk-off effect in birefringent crystal, and wavelength conversion in nonlinear optical crystals. The fundamental beams are produced from light sources selected upon the desired wavelengths, polarizations, and other features related to the laser output. Low-noise laser devices operated in SLM or with spectra of flat-top or desired bandwidths are constructed according to the method. High-volume fabrication is feasible. Apparatus of compact size and efficient frequency conversion is demonstrated with various configurations including those for generating low-noise 491 nm laser, as a replacement of Argon ion laser.

A compact solid-state laser array for nonlinear intracavity frequency conversion into desired wavelengths using periodically poled nonlinear crystals. The crystals contain dopants such as MgO and / or have a specified stoichiometry. A preferred embodiment comprises a microchip laser cavity that includes a solid-state gain chip, such as Nd:YVO4, which also provides polarization control of the laser; and a periodically poled nonlinear crystal chip such as PPMgOLN, for efficient frequency doubling of a infrared laser pump beam into the visible wavelength range. The described designs are especially advantageous for obtaining low-cost green and blue laser sources. The use of such high-efficiency pumps and nonlinear materials allows scaling of a compact, low-cost architecture to provide high output power levels in the blue / green wavelength range.

A method for producing low-noise laser output at wavelengths ranging from IR through visible to UV in various operation modes from a monolithic microchip laser comprises schemes of (1) generating one or two fundamental beam(s) from light source(s) selected upon the desired wavelength(s), polarization(s), and other features related to the desired laser output; (2) intracavity beam combination / separation due to the walk-off effect in one or more birefringent crystal(s) transparent to the propagating lights and highly anisotropic; (3) wavelength conversion in one or more nonlinear optical crystal(s); (4) compact and efficient pump source(s); and (5) minimization of intracavity loss / noise. One resonator cavity supports only one fundamental beam, which eliminates the green problem. The gain media can be selected from an extensive group of materials including isotropic and naturally birefringent crystals, with polarization dependent or independent laser emissions. Laser devices constructed in accordance with the inventive method are demonstrated with various configurations.

An optical geophone or hydrophone for detecting seismic vibrational energy comprising a laser material, which generates a lasing frequency signal, the frequency of which varies in accordance with vibrational energy incident upon the laser material, a light source occurring at an excitation frequency for providing excitation energy incident upon the laser material, so that the laser material emits light at the lasing frequency modulated by the vibrational energy and a fiber optic cable for transmitting the excitation frequency light to the laser material and receiving the frequency modulated lasing frequency for transmission to a receiver. The laser material comprises a first face and a second face, the first face being parallel to the second face. The first face is coated so that it passes substantially all of the lasing frequency light and reflects substantially all of the excitation frequency light. The second face is coated so that the second face reflects substantially all of the lasing frequency light and substantially all of the excitation frequency light. An acoustic amplifier is provided for coupling vibrational energy to the laser material, wherein the vibrational energy is incident upon a side of the laser material orthogonal or parallel to the incidence of the excitation energy.

A method for reducing speckle noise of a monolithic microchip laser with intracavity beam combining and sum frequency mixing is based on time averaging of uncorrelated speckle patterns generated from a large number of independent longitudinal modes and comprises schemes including selection of gain media and nonlinear optical materials to support broadband sum frequency mixing; adoption of gain-conjugated and / or chirped mirrors for flat-top spectra and / or mode phase diversification; multimode laser operation introduced by RF modulation; and multiplication of source modes in frequency mixing process featured with degeneration free and narrowed / uneven intervals. A device and an apparatus for generating low speckle noise red, green, blue lasers adaptable for color display systems are developed based on the inventive method.

A method of fabrication of laser gain material and utilization of such media includes the steps of introducing a transitional metal, preferably Cr2+ thin film of controllable thickness on the ZnS crystal facets after crystal growth by means of pulse laser deposition or plasma sputtering, thermal annealing of the crystals for effective thermal diffusion of the dopant into the crystal volume with a temperature and exposition time providing the highest concentration of the dopant in the volume without degrading laser performance due to scattering and concentration quenching, and formation of a microchip laser either by means of direct deposition of mirrors on flat and parallel polished facets of a thin Cr:ZnS wafer or by relying on the internal reflectance of such facets. The gain material is susceptible to utilization of direct diode or fiber laser pumping of a microchip laser with a level of power density providing formation of positive lens and corresponding cavity stabilization as well as threshold population inversion in the laser material. Multiple applications of the laser material are contemplated in the invention.

A diode-pumped laser with a direct edge coupling of a pump beam is provided. The laser includes a microchip laser cavity optically pumped by a laser diode emitting an astigmatic pump beam having a substantially elliptical beam cross-section at an output laser diode facet. The microchip laser cavity is disposed at a substantial distance exceeding 0.001″ from the laser diode pump where the astigmatic pump beam has a greatly reduced ellipticity, providing high laser output efficiency without coupling lens element between the laser cavity and the laser diode pump. The pumping arrangement is favourable for single-mode lasing. In some embodiments, the laser cavity includes nonlinear crystal for intra-cavity SHG, a saturable absorber for passive Q-switching and mode locking, and a polarizing prism.

The invention relates to a semiconductor pumped full-cavity microchip laser device with stable output wavelength, which is characterized by comprising a laser device, a temperature sensor, a temperature drive unit, a temperature control device and a refrigerating element, wherein the laser device comprises a semiconductor pumping source, a Nd:YAG crystal and a closed thermal insulation space arranged for the Nd:YAG crystal; a thermoprobe of the temperature sensor contacts with a surface of the Nd:YAG crystal; the temperature drive unit comprises an error amplifier and an H bridge; the temperature control device comprises a data acquisition card and a computer which is connected with the data acquisition card in two directions; a control and display module and a PID digital compensating network are arranged in the computer; the error amplifier and the temperature sensor are electrically connected with each other; the data acquisition card is electrically connected with the error amplifier; the control and display module compares the existing temperature digital signal with the preset standard temperature value to obtain a temperature difference value; and the PID digital compensating network carries out PID digital compensation according to the temperature difference value, and transmits the obtained feedback conditioning signal to the H bridge for power amplification, thereby driving temperature of the refrigerating element. The invention can be widely used in the fields of laser precision measurement and laser technology.

A method, an apparatus, and a module for producing dual beam from a single laser diode provide for means of simultaneously pumping two individual gain media with orthogonal polarizations. A beam splitter splits the emissive laser beam into two portions based on the polarization. A polarization control element or mechanism adjusts the polarization and the intensity ratio of the separated beam portions. Applications to monolithic microchip lasers include generating new wavelengths based on intracavity beam combining and mixing.

A solid-state laser apparatus includes a solid-state laser medium producing an output laser beam, the solid-state laser medium forming a microchip laser and having opposing end surfaces forming a laser cavity, a semiconductor laser array pumping the solid-state laser medium by a pumping laser beam, the semiconductor laser array injecting the pumping laser beam to the solid-state laser medium from a direction perpendicular to a direction of the output laser beam, the solid-state laser medium and the semiconductor laser array are mounted on a common mounting substrate.

The invention relates to a measuring system for the expansion coefficient of a material. The measuring system is characterized by comprising two solid microchip laser feedback interferometer optical systems and an electrical logging and electric control system, wherein a heating furnace is arranged between the two solid microchip laser feedback interferometer optical systems and comprises a furnace chamber; a cavity is formed in the furnace chamber; a perforating hole is symmetrically formed in the two opposite sides of the cavity outward respectively; a perforating hole packaging structure is fixedly arranged at the outer end part of each perforating hole; a window plate is fixed outside each perforating hole packaging structure through a window plate clamping seat; a sample table device capable of accommodating a sample to be measured is further arranged in the cavity body; a heating element and a temperature sensor are fixedly arranged on the inner wall of the furnace chamber in a suspended mode. The measuring system for coefficient of liner expansion has the advantages of complete non-contact, high precision, large temperature measuring range and high resistance to shock, and is particularly suitable for a relatively low surface reflecting material. The measuring system can be widely applied to large temperature range and high precision measurement of expansion coefficient of various materials.

A method, an apparatus, and a module for producing dual beam from a single laser diode provide for means of simultaneously pumping two individual gain media with orthogonal polarizations. A beam splitter splits the emissive laser beam into two portions based on the polarization. A polarization control element or mechanism adjusts the polarization and the intensity ratio of the separated beam portions. Applications to monolithic microchip lasers include generating new wavelengths based on intracavity beam combining and mixing.

A method of fabrication of laser gain material and utilization of such media includes the steps of introducing a transitional metal, preferably Cr2+ thin film of controllable thickness on the ZnS crystal facets after crystal growth by means of pulse laser deposition or plasma sputtering, thermal annealing of the crystals for effective thermal diffusion of the dopant into the crystal volume with a temperature and exposition time providing the highest concentration of the dopant in the volume without degrading laser performance due to scattering and concentration quenching, and formation of a microchip laser either by means of direct deposition of mirrors on flat and parallel polished facets of a thin Cr:ZnS wafer or by relying on the internal reflectance of such facets. The gain material is susceptible to utilization of direct diode or fiber laser pumping of a microchip laser with a level of power density providing formation of positive lens and corresponding cavity stabilization as well as threshold population inversion in the laser material. Multiple applications of the laser material are contemplated in the invention.

A diode-pumped laser with a direct edge coupling of a pump beam is provided. The laser includes a microchip laser cavity optically pumped by a laser diode emitting an astigmatic pump beam having a substantially elliptical beam cross-section at an output laser diode facet. The microchip laser cavity is disposed at a substantial distance exceeding 0.001″ from the laser diode pump where the astigmatic pump beam has a greatly reduced ellipticity, providing high laser output efficiency without coupling lens element between the laser cavity and the laser diode pump. The pumping arrangement is favourable for single-mode lasing. In some embodiments, the laser cavity includes nonlinear crystal for intra-cavity SHG, a saturable absorber for passive Q-switching and mode locking, and a polarizing prism.

Application of a modular coaxial package design, compatible with telecommunication passive component packaging, to microchip lasers, in particular to passively Q-switched microlasers, pumped with a fiber-coupled diode, is disclosed. The number of parts is thereby reduced while providing the adequate degrees of freedom for the active or passive alignment of the optical elements within the package.

The invention relates to the field of lasers, in particular to a method for achieving the adjustment of laser frequency difference and a single longitudinal mode microchip laser thereof. The method for achieving the adjustment of laser frequency difference comprises leading pump power to be basically the same through two different pump point-source light source pump lasers, and getting needed laser frequency difference through adjusting pump power difference. The invention simultaneously discloses four single longitudinal mode microchip lasers whose frequency difference can be adjusted through using the method. With the technical proposal, the invention has the advantages of miniaturization and easy installation and adjustment of LD pump, which is a novel method for achieving the adjustment of laser frequency difference and a single longitudinal mode microchip laser whose frequency difference can be adjusted.

A compact solid-state laser array for nonlinear intracavity frequency conversion into desired wavelengths using periodically poled nonlinear crystals. The crystals contain dopants such as MgO and / or have a specified stoichiometry. A preferred embodiment comprises a microchip laser cavity that includes a solid-state gain chip, such as Nd:YVO4, which also provides polarization control of the laser; and a periodically poled nonlinear crystal chip such as PPMgOLN, for efficient frequency doubling of a infrared laser pump beam into the visible wavelength range. The described designs are especially advantageous for obtaining low-cost green and blue laser sources. The use of such high-efficiency pumps and nonlinear materials allows scaling of a compact, low-cost architecture to provide high output power levels in the blue / green wavelength range.

A laser system comprises a pump diode, fiber, relay optics, and a microchip laser crystal. The pump diode produces light at a first wavelength. The fiber receives the light from the pump diode and produces a round, homogeneous light spot at an output of the fiber. The relay optics receives the light from the fiber. The microchip laser crystal receives the light from the relay optics and produces a linearly polarized single frequency output at a second wavelength. The microchip laser crystal includes a first layer and a second layer. The first layer absorbs the light at the first wavelength and emits light at the second wavelength. The second layer receives the light at the second wavelength and either provides a polarization dependent loss at the second wavelength or maintains a polarization of the light at the second wavelength.

Using immersion method to dispose rubidium (0.2-8.0wt%) in vycor laser glass. The glass contains SiO2 above 95%. In order to enhance luminescent intensity. Y3+,V5+,Al3+ immerge in it. Solid phase is exposed to air or O2 at 1000de.c to 1200deg.c and product is obtained then. The glass can exploit 1060nm laser from 808nm laser pump after polishing in laser resonant cavity. Preparing microchip laser.

The invention relates to the laser field, in particular to a method for realizing double-frequency output lasers. The method for realizing double-frequency output lasers comprises the following steps that: a first microchip laser and a second microchip laser are pumped by a pump light source, so as to ensure that the first microchip laser and the second microchip laser have optical thickness difference in cavity length, and furthermore, the range of the optical thickness difference is between 0 and 0.1 mm. The first microchip laser and the second microchip laser are a single whole through optical cement, gluing or deepened optical cement. Two single-longitudinal-mode output fundamental wave or frequency doubled laser output lasers with little difference in wavelength are formed through the pumping of the same pumping source, so as to obtain a microchip-type double-frequency laser which is used for double-frequency laser heterodyne interferometers and replaces the common double-frequency He-Ne laser. As the invention puts forward a novel method for realizing double-frequency output lasers, the double-frequency laser in small size can be obtained.

The invention relates to laser field, particularly relates to optical polarizer field. Optical principle of the invention is adoption of two wedge angle crystals with same index of refraction and made of same optical materials, relative slope of the wedge angle crystals is plated with optical material coating with different index of refraction, a single block is composed between the wedge angle crystals by optical cement or deepened optical cement. The vertical light pass surface and optical cement film of the middle slope compose a brewster angel theta, thereby a flat type portion polarizer is composed for transparent transmission of P weight polarized light and partial reflection of S weight polarized light. The invention uses the technical scheme, has a optical structure of easy implementation, less optical loss, higher damage resistance threshold value, which is suitable for producing polarizer in laser vcavity and particularly in microchip laser, and can implement efficient integration with other optical crystals or optical device.