241 results about "Random laser" patented technology

The invention discloses an automatically-extracting power line method in random laser point cloud data. According to the automatically-extracting power line method, a ground point cloud is segmented and filtered through a point cloud of an elevation; on direction projection of the segmented point cloud, a straight line segment is detected and further back-projected to three-dimensional space so as to obtain a three-dimensional line segment; while the three-dimensional line segment serves as a clustering nuclear, a distance clustering method is used to obtain an accurate point cloud of the power line and generates a power line vector node based on the accurate point cloud of the power line; and a power line vector is outputted, so that automatic extraction of the power line is realized. The automatically-extracting power line method in the random laser point cloud data is efficient in extracting, and can automatically extract the power line.

The invention discloses a dye auto-polymerized thin film random laser. The dye auto-polymerized thin film random laser comprises external pump light and a thin film sample, wherein the thin film sample consists of a glass negative and a PDMS thin film; the glass negative and the PDMS thin film together form a leakage waveguide structure; and the PDMS thin film contains an auto-aggregated dye micro-nano crystal which is formed by auto aggregation of PM597 dye molecules. The invention furthermore discloses a preparation method of the dye auto-polymerized thin film random laser. According to the dye auto-polymerized thin film random laser, the low-concentration dye molecules are low in energy of self-absorption loss, so that the threshold value of the random laser is reduced and then the energy loss of the pump light is reduced; the solubility of the dye molecules change and the dye molecules aggregate to form the micro-nano crystal which serves as a scattering medium and a gain medium in a random laser outgoing process, so that the preparation method of the random laser is simplified; and the thin film random laser is low in threshold value and simple in preparation process.

The invention discloses a PDLC (polymer dispersed liquid crystal) optical fiber doped with dye and metal nanoparticles. The optical fiber comprises a hollow optical fiber body and a PDLC polymer solidified in the optical fiber body and doped with the dye and the metal nanoparticles, an indium tin oxide (ITO) conductive layer is axially coated on the outer surface of the optical fiber body, an ITO conductive layer identical with the inner diameter of the optical fiber body in width is formed on the outer layer of the hollow optical fiber body by a vacuum magnetron sputtering method, a homogeneous solution is prepared by PDLCs and an ethanol solution of the laser dye and the metal nanoparticles according to a certain mass ratio, is absorbed into the hollow optical fiber body through the capillary effect and fills up the inner diameter of the hollow optical fiber body through light solidifying to enable the refractive index of the polymer to be larger than that of the optical fiber, and positive and negative voltage is connected through the ITO conductive layer to form an electric field to change axial directions of liquid crystal molecules so as to control outputting of random lasers. The PDLC optical fiber doped with the dye and the metal nanoparticles can be applied to aspects of optical communication, sensing, biomedicine, tunable narrow-band coherent light sources and the like.

The invention discloses a semi-open cavity random fiber laser with a low threshold. An optical wave is coupled into a standard single mode fiber (6) from a front end by a pump source (1) of the semi-open cavity random fiber laser through a wavelength division multiplexer WDM (3). A common terminal (9) of the wavelength division multiplexer WDM (3) is connected with a high-reflectivity fiber grating (4) with a specific central wavelength. A feedback in the fiber laser is provided by a randomly distributed Rayleigh scattering (10) and a fiber grating feedback (5). A tail end (7) of the optical fiber is an output end of the laser. The semi-open cavity random fiber laser with a low threshold provided by the invention has characteristics such as tunable wavelength, multi-order random laser mixed output, and simple structure. The semi-open cavity random fiber laser with a low threshold provides a new development method for related optical devices and systems, and facilitates further promotion of the application of a feedback-randomly-distributed fiber laser in the fields of optical sensing and optical communication.

A long-distance polarization and phase-sensitive reflectometry based on random laser amplification for extending a sensing distance includes a long-distance polarization and phase-sensitive reflectometry of a distributed Raman amplification based on optical fiber random lasers generated by unilateral pumps, a long-distance polarization and phase-sensitive reflectometry of a distributed Raman amplification based on optical fiber random lasers generated by bilateral pumps, and a long-distance polarization and phase-sensitive reflectometry of a Raman amplification based on a combination of optical fiber random lasers generated by unilateral pumps and a common Raman pump source, which are applied in optical fiber perturbation sensing and have a capability of greatly improving a working distance of a sensing system and a high practicability.

The invention relates to a light polarization compensation device for utilizing a beam shaping technology and a space beam combination system to convert incident laser into polarized laser to be output and belongs to the technical field of light polarization compensation. The device mainly comprises an input optical interface, a polarization beam splitter, a shaper, a first reflecting mirror, a spiral wave device, a second reflecting mirror and a space beam combiner. Against the polarization compensation problem of a laser, the light polarization compensation device aims to solve the problem of polarization instability and low extinction ratio of the laser, the lossless polarization compensation device based on the high-duty-cycle space beam combination system and the beam shaping technology is provided, and random laser is converted into high-extinction-ratio polarization laser to be output on the condition that the laser power level and beam quality are not affected. The light polarization compensation device is very small in power loss, the structure of the laser is not affected, and the cost and the complexity of the linear polarization laser can be effectively reduced; a control method for the light polarization compensation device is simple, a feedback and control system does not need to be arranged, and the light polarization compensation device is stable and reliable in performance.

The present invention relates to the technical field of intermediate infrared laser, and solves the technical problems that when an intermediate infrared passively Q-switched fiber laser in the prior art outputs an intermediate infrared laser light source at a 3[mu]m wave band, the outputted laser light source is low in energy and low in output efficiency. An all-fiber intermediate infrared high-energy passively Q-switched fiber laser comprises a random laser pumping source, a double-cladding Ho3+-doped ZBLAN optical fiber, and a single-cladding Dy3+-doped ZBLAN optical fiber which are connected in order, wherein a first fluoride fiber grating is etched at the front end of the double-cladding Ho3+-doped ZBLAN optical fiber, a second fluoride fiber grating is etched at the tail end of the single-cladding Dy3+-doped ZBLAN optical fiber, a resonant cavity is formed between the first fluoride fiber grating and the second fluoride fiber grating, thereby achieving the technical effect of outputting high-energy and high-efficiency intermediate infrared laser at the 3[mu]m wave band.

The invention discloses a dye and liquid crystal co-doped light source device-based novel tunable method. The method comprises the following steps of: performing orientation treatment on in-plane switching (IPS) glass base plates, wherein the friction direction of upper and lower glass base plates is antiparallel to a manufacturing liquid crystal box; uniformly mixing chiral liquid crystal and dye according to the proportion, heating until an isotropic phase is formed, and injecting into the liquid crystal box under the capillary action; and exciting the device by using laser of a certain wave band, applying an alternating current electric field to an IPS electrode, and allowing the light source of the device to perform wavelength tuning in the wave band of visible light by changing an additive electric field. The method has the advantages that: 1, the device has a tiny volume and high integrated level; 2, the luminous mechanism of the light source device is multiple scattering of random laser, so that monochromaticity of the light source and the luminance are high; and 3, the luminous wavelength of the light source device can be continuously tuned under the action of the electric field.

The invention discloses a random fiber laser system with tunable wavelength, belonging to the laser device field. According to the system, first pump source laser with tunable wavelength and a series of low energy seed source laser are injected into a fiber, through a series of Raman amplification effects, distributed Raman amplification light is generated in a transmission fiber, and distributedRayleigh backward diffusion light forms random laser after Raman amplification. A random laser in the invention can realize continuous tunable wavelength. In a selectable scheme, after first Raman amplification, residual energy of a first pump source or a first seed source is fed back to the fiber for reuse, and slope efficiency of a finally formed random laser is raised. The system can control aRaman gain and a shape of a Raman gain spectrum through additional seed light, reduce a threshold of the laser, and raise output power.

The invention provides a random fiber laser system and belongs to the novel laser device field. In the system, a traditional single-mode fiber is taken as a laser medium, and a cascaded semiconductor laser is taken as pump light which is coupled to the fiber along an opposite direction from a middle point of the fiber. Photon is in propagation in the fiber, scattering is generated because of nonuniform random refractive index, and distributed Rayleigh scattering is formed. The pump light provides distributed Raman gain along the fiber. When total gain is greater than total loss, backward scattered photon is amplified to generate laser. Frequency of random laser is a result of frequency of last grade pump light shifting downward with 13 THz. By properly selecting pump light, output of the random laser in a whole fiber transparent window is realized. By using cascaded semiconductor laser as the pump light, not only is Raman gain spectrum bandwidth increased, but also Raman gain form is controlled. Thereby the random laser in the invention has the characteristics of controllable mode, super-long transmission, low threshold, high output power and the like.

The invention discloses a plasmon nanometer structure-based tunable random laser array device. The random laser array device sequentially comprises a pumping light source (6), a substrate (1), a bottom electrode (21), a dielectric layer (3), a laser cavity unit (5) and a top electrode (22) from bottom to top, the laser cavity unit (5) is encircled by a spacing layer (4), and an peripheral driving circuit (7) forms a closed loop by the bottom electrode (21) and the top electrode (22). By the tunable random laser array device, two light sources can be obtained: conventional lighting light and random laser; rapid switch between the two light sources is achieved by changing a working voltage; and moreover, compared with existing random laser devices, the obtained random laser has the advantages of low threshold, dynamic direction tunability, high efficiency and the like.

The invention discloses a random fiber laser system. According to the system, an optical fiber serves as a laser medium, and a fiber laser comprising a crystal fiber laser, a nonlinear fiber laser, a rare earth doped fiber laser and a plastic fiber laser serves as pump light to be coupled into the optical fiber. Because the refractive index of the optical fiber has non-uniformity and is randomly distributed along the optical fiber, so that the photon is subjected to rayleigh scattering during transmission in the optical fiber; and moreover, the pump light provides gain for the backward scattered light along the optical fiber, when the overall gain is greater than the total loss, the backward scattered light is amplified to form random laser. A discrete optical component is not arranged in the light path of the system, so that all-fiber connection is realized. In the system, the residual pump light is returned to the optical fiber, and the distributed weak scattered light is amplified, and therefore, according to the random fiber laser system, the threshold power of the pump light can be reduced, the utilization rate of the pump light can be improved, and the slope efficiency of the laser is improved.

The invention discloses an electric pumping random laser of silicon zinc oxide nano-rod array, wherein a ZnO film, a ZnO nano-rod array, a SiO2 film and a semitransparent electrode are sequentially formed from bottom to top on the front side of a silicon substrate, and an ohmic contact electrode is deposited at the back side of the silicon substrate. The invention further discloses a preparation method of the electric pumping random laser, including the followings: the ZnO film is formed on n-type silicon chip after cleaning by using magnetron sputtering method; the ZnO nano-rod array is formed on the ZnO film by using chemical water bath deposition method, and heat treatment is carried out under air atmosphere; the SiO2 film is formed on the ZnO nano-rod array by using sol-gel method; and the semitransparent electrode is spattered on the SiO2 film, and the ohmic contact electrode is spattered on the back side of the silicon substrate. The electric pumping random laser of silicon zinc oxide nano-rod array in the invention has simple structure, and ultraviolet electric pumping random laser from ZnO nano-rod array can be obtained under the condition of enough forward bias (Si being connected with the cathode).

The invention discloses a random laser based on Fresnel reflection of fiber flat surface and relates to the field of a high-power fiber laser. The laser comprises a pump light source, a wavelength division multiplexer, a band elimination filter and a single-mode fiber; the wavelength division multiplexer is provided with two input ports and one output port; the pump light of the pump light source is input to the wavelength division multiplexer via one input port and the other input port only allows the passing of first-order Stokes light, is connected to a fiber with a flat surface at the tail end and reflects the first-order Stokes light of the pump light from the inside of the fiber by stimulated emission; the output end of the wavelength division multiplexer is connected with the input end of the band elimination filter via the fiber; the output end of the band elimination filter is connected with one section of the single-mode fiber; the tail end of the single-mode fiber is an inclined surface and is used as the output end of the laser. The maximum output power of the first-order random laser is further increased and the output of the high-power and first-order random laser with light conversion rate of greater than 80% is obtained.

A white light random laser outputs a three primary colors by the aid of a laser pump mixed with dyes, and acquires white lights with narrow line width and high strength by means of using titanium dioxide (TiO2) nanoparticles as random scatterer for providing positive feedback, wherein the three primary colors comprise red, green and blue. The dyes used for generating the three primary colors of red, green and blue include coumarin 440 (C-440), coumarin 6 (C-6), pumping source of 355nm light and Oxazine with pumping source of 532nm. The basic principle of the white light random laser includes that by the aid of the nanosecond pulsed laser pumping with a 355nm wavelength, red light (R) is generated by means of coumarin C-440 blue light (B), coumarin C-440 green light (G) and a litter portion of light close to the 532nm green light as pumping oxazine, and most of the light close to the 532nm green light is used as the green light (G) of the white light. The white light random laser adopts the random laser principle, and outputs lasers by using titanium dioxide nanoparticles as random scatterer for providing positive feedback.

The invention discloses a method used for adjusting and controlling the outgoing wavelength of a random laser through changing thickness. The method comprises the following steps of: firstly taking gaskets with different thicknesses to respectively fill on two ends between two glass substrates of the random laser, manufacturing an interfinger structure with thickness gradient variation, wherein the thickness of the two gaskets is in a range of 3-300 mu m; then, filling a disordering gain dielectric in an interfinger, and subsequently utilizing a convergence lens to converge a pump light bundle to a disordering gain dielectric layer of the random laser; and when an optical pumping random laser is in different thicknesses, detecting emergent light of different wavelengths in front and back, and not needing to carry out an adjust and control such as electric field and temperature. The method provided by the invention guarantees the outgoing characteristic of the dynamic adjust and control random laser, with no need of changing the conditions such as ambient temperature, the electric field and illumination, and has the advantages of simple structure, convenience in manufacturing, and low environmental disturbance; and a large area optical pumping is utilized to obtain a laser bean of a width spectrum.

The invention discloses a method for compensating the influence of environmental temperature on a liquid crystal random laser through voltage. The method comprises the following steps: firstly, focusing a pump light emitted from a laser by lens, and irradiating focused pump light to a liquid crystal random laser, wherein the liquid crystal random laser is of a box-shaped structure composed of two pieces of glass, the gain medium of the liquid crystal random laser is a mixture solution composed of liquid crystal microdrop and laser dye; then, placing a detector before or behind the liquid crystal random laser so as to detect emitted random laser; and subsequently, applying a basic voltage to the liquid crystal random laser through a glass layer, when the environmental temperature is higher than the optimal working temperature of the liquid crystal random laser, modulating a power supply so as to reduce a loaded voltage value, and when the environmental temperature is lower than the optimal working temperature of the liquid crystal random laser, modulating the power supply so as to boost the loading voltage value. The influence of the environmental temperature on the liquid crystal random laser is modified effectively in a mode of boosting the voltage; and the device is simple in structure, convenient to manufacture and easy to realize.

The invention discloses a wavelength-tunable liquid crystal random laser device. The wavelength-tunable liquid crystal random laser device comprises a pump light source, flat-plate photonic crystal liquid crystal micro resonant cavity, wherein the flat-plate photonic crystal liquid crystal micro resonant cavity is connected with the pump light source through a transmission optical fiber, and comprises a fiber core and a plurality of round air holes; the fiber core is arranged at the center of the flat-plate photonic crystal liquid crystal micro resonant cavity and is used for filling liquid crystal scattering media; the round air holes are arranged at the periphery of the fiber core; and the liquid crystal scattering media filled in the fiber core are nematic liquid crystals doped with a laser gain medium and scattering particles. The invention has the advantages that the wavelength is tunable, the width of generated laser emission spectral bands is narrow, and the quality factor which can reach above 10000.

The invention discloses an external cavity type fiber laser sensor based on random feedback. The external cavity type fiber laser sensor comprises a pump light source, a laser coupled device, a filled-type special optical fiber, an external cavity structure and a frequency spectrum-mode field analysis device, wherein the external cavity structure is composed of a crossed hollow core glass tube, the crossed hollow core glass tube is embedded in the filled-type special optical fiber, and the joint of the hollow core glass tube and the filled-type special optical fiber is adhered and sealed by adopting an optical cement, so as to form a resonant cavity for random fiber lasers; the crossed hollow core glass tube comprises an upper hole and a lower hole, a sample to be tested enters the resonant cavity through the upper hole and flows out from the lower hole; the pump light source is used for generating light waves, and the laser coupled device is used for coupling the light waves in the filled-type special optical fiber to stimulate random lasers; the output light waves of the resonant cavity are coupled to enter the frequency spectrum-mode field analysis device to carry out frequency spectrum and mode field information analysis.

The invention relates to semiconductor quantum dot doped polymer dispersed liquid crystal containing Ag nanoparticles and a preparation method thereof. The semiconductor quantum dot doped polymer dispersed liquid crystal containing the Ag nanoparticles is prepared from the following components in parts by mass: 1 to 5 parts of semiconductor quantum dots, 20 to 74 parts of a photosensitive polymer,20 to 78 parts of nematic liquid crystal, 1-5 parts of a photoinitiator, and 0.5 to 1.5 parts of Ag nano particles. The invention also relates to an application of the semiconductor quantum dot dopedpolymer dispersed liquid crystal containing the Ag nanoparticles in a random laser. The semiconductor quantum dot doped polymer dispersed liquid crystal containing the Ag nanoparticles has the advantages that the raw materials are simple and easy to obtain;, and the cost is low; the obtained random laser has the advantages of short preparation period, simple preparation process, easy regulation and control of emission wavelength, low production cost, higher intensity of emitted light, low threshold value and the like; and the semiconductor quantum dot doped polymer dispersed liquid crystal containing the Ag nanoparticles has a wide commercial application prospect.

The invention discloses a plasmon random laser array device based on a two-dimensional material. The plasmon random laser array device consists of an array of laser chamber units; the integral structure of the random laser array device comprises a pumping light source (1), a substrate (2), bottom electrodes (31), a medium layer (4), laser chamber units (6) enclosed by spacing layers (5) and a top electrode (32) which are successively arranged from the bottom to the top; two ends of a periphery driving circuit (7) are respectively connected to the bottom electrodes (31) and the top electrode (32); the bottom electrode (31), the medium layer (4), the laser chamber units (6) and the top electrode (32) form a closed circuit. The random laser array uses the two-dimensional material nanometer sheet which has high photoluminescence efficiency as a random gain medium, can effectively enhance light scattering through the localized surface plasmon resonance (LSPR) of metal nanometer particles and can reduce the threshold of the laser. Besides, the Plasmon random laser array device can perform dynamic regulation on a radiation spectrum and directivity through changing working voltage of the laser chamber.

The invention discloses a random fiber laser for hybrid of a special fiber and a standard single mode fiber, which belongs to the technical field of novel lasers, and comprises a pump light source, a wavelength division multiplexing device WDM provided with three ports, and the special fiber, wherein the pump light source, the wavelength division multiplexing device WDM, the standard single mode fiber, and the special fiber are connected in sequence; an open resonant cavity is formed by the standard single mode fiber and the special fiber, so that a random resonant mode is formed; pump light emanated by the pump light source is coupled with the standard single mode fiber and the special fiber through the wavelength division multiplexing device WDM to obtain strong rayleigh scattering and high Raman gain, when the gain is greater than the loss, random laser output is realized at the fiber tail-end. The random fiber laser has the characteristics of low pump threshold value, tunable wavelength, stable output, and simple structure, which provide a new way for the development of related optical devices and systems, and meanwhile facilitate the further pushing of the application of the random distributed feedback fiber laser in the field of optical sensing, optical communication, and the like.

The invention discloses a Q-modulated multi-frequency mode-locked fiber random laser comprising a fiber totally-reflective mirror 1, a saturable absorber 2, a coupler 3, a polarization controller 4, a pump light source 5, a wavelength division multiplexer 6, and an active fiber 7. A stochastic feedback and photon local effect introduced by a random resonant cavity structure enables laser output to be in multiple possible modes. In addition, multiple high-order harmonic sub pulses can be produced while a linear cavity resonates to produce low-frequency mode-locked pulse, namely, pulses of multiple frequencies can be acquired in a very wide frequency range. The repetition frequencies of pulse include both high frequency and low frequency. However, the pulse repetition frequency of the traditional typical mode-locked laser corresponds to a determined cavity length, there is a single pulse frequency, and the adjustable range is narrow.

The invention discloses a hybrid cavity type dual-wavelength narrow linewidth optical fiber laser, relates to the field of a laser and aims at solving the problem that in the prior part, dual-wavelengths or multi-wavelengths are generally generated in a fixing cavity or a random cavity independently and narrow linewidth traditional lasers and random lasers cannot be output at the same time. According to the hybrid cavity type dual-wavelength narrow linewidth optical fiber laser, a linear resonant cavity is driven through two lasers emitted by two pump lasers; two narrow linewidth lasers are symmetrically output through oscillation tuning of the linear resonant cavity; the random cavity is driven by the two narrow linewidth lasers output by the linear resonant cavity; two ultra-narrow linewidth Brillouin random lasers through oscillation tuning of the random cavity; two different cavity structures and two different gain mechanisms are realized in the same system; and the narrow linewidth traditional lasers and random lasers are output at the same time under the effect of the same pump source. The hybrid cavity type dual-wavelength narrow linewidth optical fiber laser applies to the field of a laser technology and the laser.