16 results about "Thermal lensing" patented technology

The application relates to the technical field of continuous laser optical film, in particular to a low-heat-effect laser film and a preparation method thereof. The method comprises the following steps: designing a film system according to laser wavelengths and optical performance and simulating and optimizing; precisely polishing a substrate, ultrasonic cleaning and activating; alternately preparing high and low refractive index functional layers and interface modification layers by physical vapor deposition and atomic layer deposition, setting the interface modification layers between the adjacent high and low refractive index functional layers, forming a periodic stacking structure; and annealing treatment under an inert atmosphere at 150-300 DEG C to obtain a finished product. The method has the advantages that: phonon bridging and interface passivation are realized through nano-Al2O3 interface modification, interface thermal resistance is significantly reduced, heat accumulation and thermal lens effect are inhibited, and the laser damage threshold is improved; the process is controllable, the film layer is dense and uniform, and the method is suitable for antireflection, high-reflection or light-splitting devices of high-power continuous laser systems.

This invention provides a reliability prediction and aging screening method for InP optical communication laser chips, relating to the field of semiconductor laser manufacturing and reliability assessment technology. The method first induces a transient thermal lensing effect through asymmetric bipolar current perturbation, then uses reverse bias to clear charge interference, capturing the dynamic resistance and wavelength chirp sequence reflecting lattice dislocation climb. Subsequently, a physical failure mode database is constructed, and intrinsic thermal damping is stripped in the frequency domain, mapping degradation features to epitaxial stress relaxation and nonradiative recombination mechanisms to achieve in-depth defect fingerprint analysis. Finally, based on a physically embedded deep learning architecture, the carrier rate equation and entropy increase law are used as constraints for lifetime prediction, and the second derivative of the predicted trajectory is used to evaluate the remaining lattice structure margin. This invention solves the problems of insufficient latent defect identification and predictions violating physical laws, achieving high-precision performance grading and risk interception.

This invention discloses a holmium ion-doped yttrium gadolinium oxide single-crystal optical fiber, its preparation method, and its applications, belonging to the field of laser materials and laser technology. The chemical formula of the single-crystal optical fiber is Ho. 3+ YGdO3, wherein the Ho ion doping concentration is 0.2-1.0 at.%, is a cubic C-type sesquioxide crystal structure with space group Ia-3. This crystal exhibits characteristic absorption peaks at wavelengths of 1100-1200 nm and Ho-derived absorption peaks at 2.80-2.90 μm. 3+ ion 5 I6→ 5 Broad-spectrum mid-infrared fluorescence emission with I7 level transition; this crystal possesses a wide gain bandwidth, a large emission cross section, and excellent thermal properties, making it less prone to thermal lensing and thermal depolarization under continuous or high-repetition-rate pumping of single-crystal fibers, thus ensuring high stability of laser output. It is particularly suitable for realizing broadband tunable and ultrafast mode-locked mid-infrared lasers, and has broad application prospects in laser surgery, environmental monitoring, remote sensing, and other fields.

A method of altering a refractive property of a crosslinked acrylic polymer material by irradiating the material with a high energy pulsed laser beam to change its refractive index. The method is used to alter the refractive property, and hence the optical power, of an implantable intraocular lens after implantation in the patient's eye. In some examples, the wavelength of the laser beam is in the far red and near IR range and the light is absorbed by the crosslinked acrylic polymer via two-photon absorption at high laser pulse energy. The method also includes designing laser beam scan patterns that compensate for effects of multiphone absorption such as a shift in the depth of the laser pulse absorption location, and compensate for effects caused by high laser pulse energy such as thermal lensing. The method can be used to form a Fresnel lens in the optical zone.

This invention discloses a laser frequency conversion system and method based on thermal lensing effect enhancement, belonging to the field of laser technology. The system includes a first pump source, a nonlinear frequency conversion crystal, and a second pump source. The crystal is a rare-earth-doped calcium borate crystal, which absorbs the first pump light to generate a controllable thermal lensing effect. The fundamental wave light emitted from the second pump source is coaxially incident on the crystal with the first pump light. The thermal lens focuses the fundamental wave light, significantly increasing its power density within the crystal. The crystal then utilizes a nonlinear optical effect to efficiently convert the high-power-density fundamental wave light into harmonic light output. This invention solves the problem of low efficiency in traditional extracavity frequency doubling. Through an active focusing mechanism, high-efficiency and high-stability visible light laser output can be achieved with only a lower fundamental wave power, making it particularly suitable for biological detection and medical aesthetics.

This invention proposes a gallium nitride-based semiconductor laser, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer. This invention incorporates a multi-layered, multi-vacancy electron-phonon modulation layer within the semiconductor laser element, defining the electron affinity distribution and polarization optical phonon energy distribution characteristics of each multi-vacancy electron-phonon modulation layer. This forms single-vacancy, vacancy cluster, and multi-vacancy modulated electron-phonon structures, localizing electron-phonons between the lower confinement layer and the lower waveguide layer. This reduces the Stokes shift caused by the photon energy difference between the pump light and the oscillating light, reduces heat loss from phonon vibration and phonon transport, improves the heat dissipation of the laser element, mitigates interlayer thermal mismatch, suppresses the thermal lensing effect and stress birefringence effect of the laser, improves laser beam distortion and depolarization, and enhances the laser beam quality factor.

This invention discloses a laser welding device with a laser welding head cooling mechanism, comprising: a laser welding head, with a housing on each of the left and right sides; copper tubes, which are respectively inserted through and fixed to the front of the inner walls of the two housings, with several water outlets on the back of the copper tubes; several water pipes, which are respectively fixed to the back of the water outlets of the two sets of copper tubes; a cold water plate, which is fixedly installed on the inner walls of the two housings; a cooling assembly, which is disposed on the front of the cold water plate; a U-shaped plate, which is fixed to the back of the cold water plate; and two guide rods, which are fixed to the bottom and top of the U-shaped plate. This invention uses a tank shell to evenly blow gas to the back of the laser welding head, thereby avoiding the problem of heat accumulation in a localized area of ​​the laser welding head, which causes thermal lensing effect and beam quality degradation.

Exemplary thermoelectric devices and methods are disclosed herein. Thermoelectric generator performance is increased by the shaping isothermal fields within the bulk of a thermoelectric pellet, resulting in an increase in power output of a thermoelectric generator module. In one embodiment, a thermoelectric device includes a pellet comprising a semiconductor material, a first metal layer surrounding a first portion of the pellet, and a second metal layer surrounding a second portion of the pellet. The first and second metal layers are configured proximate to one another about a perimeter of the pellet. The pellet is exposed at the perimeter. And the perimeter is configured at a sidewall height about the pellet to provide a non-linear effect on a power output of the thermoelectric device by modifying an isotherm surface curvature within the pellet. The device also includes a metal container thermally and electrically bonded to the pellet.

This invention discloses a dynamic thermal lens compensation method based on an unstable resonant cavity, comprising: (1) deriving the abcd matrix of light traveling one round trip in the cold cavity according to a repetition frequency of 1 Hz, and calculating its geometric magnification; (2) measuring the focal length of the thermal lens at different repetition frequencies; (3) fixing the distances from the output mirror and the original total reflection mirror in the resonant cavity to the end face of the crystal, and replacing the original total reflection mirror with a planar total reflection mirror; (4) deriving the ABCD matrix of light traveling one round trip in the compensation cavity according to the focal length of the thermal lens corresponding to different repetition frequencies, and calculating its geometric magnification; (5) setting the distance between the planar total reflection mirror and the left end face of the crystal as a variable, making the geometric magnification of the compensation cavity equal to that of the cold cavity, and calculating the corresponding distance between the planar total reflection mirror and the left end face of the crystal; (6) constructing the final compensation unstable cavity according to the distance between the planar total reflection mirror and the left end face of the crystal, thus completing the thermal lens compensation. This invention achieves dynamic compensation of the focal length of the thermal lens corresponding to different repetition frequencies using simple operations.

The application relates to the technical field of laser amplification. A laser amplification system comprises a gain module and a mirror reflection module. The gain module has a first reflection surface and a gain medium which are stacked. The first reflection surface is used for reflecting laser light. The first reflection surface is recessed from the gain medium towards the first reflection surface. Laser light is incident into the first reflection surface from the gain medium towards the first reflection surface. The mirror reflection module is located on the reflection side of the gain module and comprises a plane mirror and a folded mirror. The folded mirror is located between the gain module and the plane mirror. The folded mirror comprises a second reflection surface and a third reflection surface which are perpendicular to each other and face the plane mirror. The second reflection surface and the third reflection surface are used for making the laser light incident into the folded mirror and the laser light emitted from the folded mirror parallel. The laser amplification system satisfies the above structure, realizes folding of the optical path of laser light, and can compensate for thermal lens effect in the laser amplification system.

The application belongs to the technical field of laser, and discloses a steady-state simulation method, equipment and storage medium of a solid laser. A pump source model is constructed to calculate pump light intensity and photon flux; a crystal heat source distribution is solved based on the pump light intensity, a three-dimensional temperature field and a thermal lens focal length are obtained by using a step-by-step Fourier solving method; the stability is analyzed by dynamically updating the equivalent g parameter and the curvature radius of the resonant cavity by using the thermal lens focal length; the pump absorption and gain distribution are calculated in combination with the pump light intensity, the photon flux and the crystal boundary reflection characteristics; the pump-laser mode overlap factor is calculated based on the beam parameter calculated according to the equivalent g parameter, the pump light intensity and the laser light intensity; the laser threshold power is calculated, and the output power is calculated in combination with the threshold power and the input pump power; the steady-state laser field is iteratively solved based on the equivalent g parameter, the thermal lens focal length and the gain distribution, and finally the simulation result is output, the dynamic coupling feedback of the thermal lens focal length and the resonant cavity parameter is realized, and the simulation precision is significantly improved.

To provide a glass material and a magnetic optical element with a reduced thermal lens effect. A glass material contains, in mol %, from 10% to 90% of Tb2O3, from 1% to 89% of B2O3+Al2O3+SiO2+P2O5, and from 0.01 ppm to 100 ppm of FeO+Fe2O3, and further contains, as an external proportion, from 0.001% to 1% of CeO2.

A spectral beam combiner (50) comprises at least one transmitting volume chirped Bragg grating, TVCBG, (24, 62) configured to diffract a first broadband beam (42, 66) propagating at one central wavelength, which satisfies the Bragg condition, and incident on the TVCBG (24, 62) at one of (+) (-) Bragg angles, transmit at least one second broadband beam (40, 68) propagating at a second central wavelength, which does not satisfy the Bragg condition, and incident on the TVCBG (24, 62) at the Bragg angle which is opposite to the one Bragg angle of the first broadband beam (42, 66), and combine the diffracted first (42, 66) and transmitted second (40, 68) broadband beams into a first single high-power collimated broadband output beam. The spectral beam combiner (50) further comprises a first thermal lens compensator, wherein a thermal lens is induced in the one TVCBG (24, 62) by one of or both first and second broadband beams (40, 42, 66, 68). The first thermal lens compensator includes a holographic achromatic broadband phase mask, HAPM, recorded in a designated PTR, photo-thermo-refractive, glass plate (35) which is located downstream from the one TVCBG (24, 62) or recorded in a PTR glass plate (35) with the one TVCBG (24, 62) and / or a pair of holographic phase masks, HPM, which are aligned at respective opposite Bragg angles upstream from the one TVCBG (24, 62), the HPMs diffracting the second broadband beam (40, 68) while converting a Gaussian intensity profile thereof to a donut-shaped intensity profile.

This invention discloses a long-range, non-contact obstacle removal system and method based on laser, including a portable laser obstacle removal case, a laser support, and a laser obstacle removal device. The portable case is connected to the laser obstacle removal device via a cable. A servo motor gimbal is mounted on the top of the laser support, and the laser obstacle removal device is mounted on the servo motor gimbal. The laser obstacle removal device includes: a fiber laser for generating obstacle removal laser; an optical path guiding mirror group for transmitting the generated obstacle removal laser; a focusing and directional mirror group for orienting, zooming, and focusing the generated obstacle removal laser so that it acts on the obstacle removal target; and a laser stabilization component for protecting the focusing and directional mirror group and maintaining laser stability. This invention improves the position of the laser obstacle removal device's emission port to avoid thermal lensing effects, ensuring laser concentration and accuracy, allowing the laser to act more precisely on the obstacle removal target, thereby efficiently completing the obstacle removal work.

This invention discloses a high-precision laser cutting positioning device for stainless steel watch case blanks, belonging to the field of laser cutting technology. It includes a plasma-flow field disturbance calculation module, a mechanical-electromagnetic perturbation calculation module, an environmental-optical drift calculation module, an optical-polarization condition adaptation calculation module, a micro-flow pulsation amplitude optimization module, and an actuator. By generating plasma-flow field disturbance coefficients, mechanical-electromagnetic perturbation coefficients, environmental-optical drift coefficients, and optical-polarization condition adaptation, and then using the mechanical-electromagnetic perturbation coefficient as an adjustment factor, the cooling water pulsation amplitude is optimized using a hyperbolic tangent function based on the adaptation deviation. This drives a proportional valve to regulate the flow pulsation, and the positioning error caused by external disturbances and optical mismatch is compensated by the micro-oscillation of the thermal lens focus. This invention achieves adaptive high-precision positioning compensation under multi-field coupled disturbances, significantly improving the dimensional consistency and cross-sectional quality of watch case blank cutting.

The application discloses a gradient refractive index lens-based optical beam shaping system and a design method thereof. The optical system comprises at least one divergent gradient refractive index lens and at least one convergent gradient refractive index lens. The divergent gradient refractive index lens and the convergent gradient refractive index lens are combined along the same optical axis. The arrangement order and the relative position relationship of the gradient refractive index lenses in the optical axis direction are designed, so that the optical system forms an afocal optical path structure as a whole. The optical system is used for transverse scale regulation of an incident light beam. On the premise of maintaining the approximate collimation propagation characteristics of an output light beam, the optical system realizes beam expansion, beam contraction and beam shaping. The structure can avoid the thermal lens effect in high-power laser, improve the stability and reliability of the system, support close fitting, cascade expansion and direct coupling with an optical fiber, and is convenient for miniaturization and integrated application.