51results about How to "Realize all-fiber" patented technology

The invention relaters to the weakly light signal detection field, especially to a kind of high-effect infrared single photon detection method including the infrared single photon signal source, the pumping source, the nonlinear crystal, the single photon signal channel and pumping light channel. It is characterized in that the pumping source is composed by the optical fiber laser; the infrared single photon signal inputted by the optical fiber transmission and the pumping light inputted by the optical fiber laser are coupled by the optical fiber polarized controller separately, which are inputted into the wavelength division multiplexer. The output pumping and signal light are outputted by one optical fiber collimator, which can save the complex system accesspries and adjusting process. It has the compact structure, good portable. The laser power is outputted stably, also it has good mode and easy for nonlinear coupling, so it can reach the good room mode matching of two beams in nonlinear crystal. The whole detector can be made by all optical fiber and has low energy cost. It is also convenience to connect other optical fiber devices and reaches the alter use of many systems.

The invention relates to a laser of semiconductor laser seed pulse principal oscillation enlarge entire optical fiber, the output of the seed light system connects to the optical fiber amplifier with the optical fiber isolator. The seed light system includes the signal mixer, the bias current supply and the modulation supply oscillator which meets the signal mixer input end, the semiconductor laser chip which meets the signal mixer out-port, the out-port of semiconductor laser chip constitutes the out-port of the seed light system. The optical fiber amplifier includes the optical fiber optical coupler, the semiconductor laser which meets the input end of the optical fiber optical coupler, the doping optical fiber which meets the out-port of the optical fiber optical coupler, the another end of the dopes optical fiber constitutes the out-port of the optical fiber amplifier. The input end of optical fiber optical coupler constitutes the input end of the optical fiber amplifier. The invention has solved the technical question of big volume, bad stability in the background technology. The invention has used the entire optical fiber structure, the frequency of the output laser is adjustable, the pulse width is adjustable.

The invention discloses an ytterbium-doped full-optical-fiber optical frequency comb system and relates to the technical field of frequency comb measurement. The system utilizes an ytterbium-doped full-optical-fiber annular cavity mode-locked laser to achieve mode-locked laser pulse output under the non-linear polarization rotation condition, achieves control chromatic dispersion in a cavity through a first band gap photonic crystal fiber and accordingly reduces in-cavity noise. An ytterbium-doped double-clad optical fiber amplifier is utilized to perform mode-locked laser pulse amplification, and a second first band gap photonic crystal fiber is utilized to achieve compression of mode-locked laser pulse width. Compressed mode-locked laser pulses pass through a tapering photonic crystal fiber welded with an optical fiber compressor to achieve output of an octave super-continuous spectrum. The full-optical-fiber performance of the whole ytterbium-doped full-optical-fiber optical frequency comb system achieves is achieved, repetition frequency and original frequency of an optical frequency comb can be locked, and the stability and portability of the ytterbium-doped optical frequency comb with a full-optical-fiber structure are improved.

The invention discloses a multi-parameter sensor based on a photonic crystal fiber. An input end and an output end of the sensor are respectively provided with an input coupler and an output coupler, an annular photonic crystal fiber cavity is formed in the way that a section of hollow photonic crystal fiber is connected between the two couplers, and the section of hollow photonic crystal fiber is used as a sensing head of the multi-parameter sensor. The invention also discloses a multi-parameter measurement system which comprises a signal acquiring, processing and displaying module and the multi-parameter sensor, the sensor is respectively connected with a light source and a photoelectric detector through the input coupler and the output coupler thereof, and the photoelectric detector is connected to the signal acquiring, processing and displaying module. The invention additionally provides a pressure measurement system comprising the multi-parameter measurement system and a pressurizing device arranged on the sensing head, and the pressuring device comprises a plenum chamber, a photonic crystal fiber clamp, a connector and the like. The multi-parameter sensor and measurement system of the invention has the advantages of simple and convenient operation, simplified structure, high measurement precision, easy miniaturization and standardization design and the like.

The invention discloses a linear-cavity active Q-switching all-fiber laser. The laser is characterized in that a linear cavity is provided, the output tail of a pumping semiconductor laser is connected with the pumping input port of a fiber beam combiner; the fiber output port of the fiber beam combiner is connected with a high-reflectivity fiber bragg grating; the other terminal of the high-reflectivity fiber bragg grating is welded with gain fibers together; the other terminal of the gain fibers is welded with a low-reflectivity fiber bragg grating formed on polarization-preserving fiber; an adjustable piezoelectric element signal drive circuit is used for driving a piezoelectric element to press fiber in the cavity periodically to modulate the polarization direction of light; the other terminal of the low-reflectivity fiber bragg grating is connected with the input terminal of a fiber isolator; and the output fiber is connected with the output terminal of the fiber isolator. The laser provided by the invention has the advantages of little insertion loss, simplified structure, high repeating frequency of laser pulses, low cost and easiness in industrialization. Large-diameter core double-cladding gain fibers can be used in the laser cavity, so that high-energy high-power laser pulses can be obtained conveniently.

The invention provides a fiber femtosecond laser generating device and method based on triangular pulse passive forming and belongs to the technical field of ultrafast laser. The device comprises a fiber passive mode-locked laser, a negative dispersion chirped fiber grating, a positive dispersion nonlinear passive fiber, a positive dispersion fiber amplifier, and a dispersion compensator. The fiber passive mode-locked laser produces an ultra-short laser pulse that passes through the negative dispersion chirped fiber grating to be converted into an ultra-short laser pulse with a negative chirp.The ultra-short laser pulse with the negative chirp is coupled into the positive dispersion nonlinear fiber to form a triangular narrow-band ultra-short laser pulse. The triangular narrow-band ultra-short laser pulse is coupled into the positive dispersion fiber amplifier to complete pulse self-similar amplification evolution and form a parabolic broadband linear chirped pulse. The broadband linear chirped pulse enters the dispersion compensator. The dispersion compensator compensates for the positive chirps accumulated by the broadband linear chirp pulse in the self-similar amplification process, to obtain the femtosecond laser with Fourier transform limit pulse quality.

The invention relates to technical fields of optical fibers and laser, and specifically relates to an incoherent beam combination-based high-energy nanosecond pulse all-fiber laser. The incoherent beam combination-based high-energy nanosecond pulse all-fiber laser is characterized by comprising a nanosecond pulse seed laser, an optical fiber beam splitter, optical fiber amplifiers, synchronous optical paths, an optical fiber beam combiner and a laser output end, wherein the output end of the nanosecond pulse seed laser is connected with the input end of the optical fiber beam splitter; the corresponding optical fiber amplifiers are arranged at the output ends of the sub paths of the optical fiber beam splitter respectively; the optical fiber beam splitter is used for performing branching on an optical signal from the nanosecond pulse seed laser, and then performing amplification on each sub path optical signal of the optical fiber beam splitter separately; the output ends of the sub paths of the optical fiber beam splitter are connected with the input ends of the corresponding optical fiber amplifiers; the output ends of the optical fiber amplifiers are connected with the input end of the optical fiber beam combiner through the synchronous optical paths separately; and the output end of the optical fiber beam combiner is connected with the laser output end. The incoherent beam combination-based high-energy nanosecond pulse all-fiber laser has the advantages of high average power, high pulse energy, small size, easy maintenance, stability, reliability and the like.

The invention belongs to the field of laser devices, and particularly relates to an acousto-optic Q-switched ytterbium-doped all-fiber laser. In order to solve the problems of low coupling efficiency, high maladjustment sensitivity, complex experimental facilities and the like caused by separated component structure in Q-switched fiber laser, the invention adopts a technical proposal of the acousto-optic Q-switched ytterbium-doped all-fiber laser which comprises a fiber bragg grating (FBG), an acousto-optic modulator (AOM) with tail fiber, a multimode coupler, two pumping light-emitting diodes (LDs), ytterbium-doped double-clad fiber and output tail fiber, wherein the two pumping LDs couple pumping light to the ytterbium-doped double-clad fiber respectively by the multimode coupler; the ytterbium-doped double-clad fiber is connected between the output terminal of the multimode coupler and the output tail fiber; the FGB is connected to a signal terminal of the multimode coupler by the AOM with tail fiber, and forms a resonant cavity with the end surface of the output tail fiber simultaneously; and alternating voltage is applied on the AOM. The invention is mainly used in the manufacturing and designing of lasers.

The present invention relates to an integrated all-fiber passive Q-switched pulsed fiber laser. The integrated all-fiber passive Q-switched pulsed fiber laser is realized through an in-band pumping mode and on the basis of the dual-cavity coupling principle. The working wave bands of resonant cavities are reasonably designed on the basis of full utilization of the characteristics of the wide absorption bandwidth and transmission bandwidth of doped gain fibers and the large cross and overlapping range of the wide absorption bandwidth and transmission bandwidth; the gain function and saturation absorption function of laser radiation are realized in the doped gain fibers; the radiated laser of a first resonant cavity is utilized to pump a second resonant cavity; the integrated all-fiber passive Q-switched pulsed fiber laser is realized through the coupled cavity; and the core diameter of the fiber core of a second resonant cavity doped gain fiber and the core diameter of the fiber core of a first resonant cavity fiber doped gain fiber are different, and therefore, the energy density of laser in the second resonant cavity doped gain fiber is improved, and the bleaching and switching capability of a passive saturable absorber can be improved. The pulsed fiber laser of the invention has the advantages of compact structure and stable performance. The all-fiber-based performance of the pulsed fiber laser can be realized truly.

The invention is applicable to the technical fields of optical fiber and fiber lasers, and provides photonic bandgap fiber (PBGF). The PBGF comprises a cladding layer and a fiber core wrapped in the cladding layer, wherein, the internal cladding layer is formed by a ring composed of large air holes, and the internal cladding layer contains germanium (Ge)-doped glass wires; and the fiber core contains a fluorine (F)-doped area with low refractive index. In the invention, slight refractive index subsidence is applied to the fiber core of the all-solid-state PBGF, which effectively enhances resonance coupling between a mode field and the Ge-doped glass wires in a 'loss zone' and further reduces the number of the Ge-doped glass wires in the cladding layer and absorption of the glass wires in the cladding layer on pump light.

The invention provides a D-shaped fiber-based cross-polarization beat laser and a sensor. The laser comprises a pump laser, a wavelength division multiplexer connected with the pump laser, a first fiber Bragg grating, one end of which is connected with the wavelength division multiplexer, a second fiber Bragg grating, one end of which is connected with an output fiber, and an erbium-doped D-shaped fiber which is encapsulated between the other end of the first fiber Bragg grating and the other end of the second fiber Bragg grating, wherein the first fiber Bragg grating, the second fiber Bragg grating and the erbium-doped D-shaped fiber are integrated on one fiber. The distributed fiber grating is adopted as a reflector to form an ultrashort resonant cavity, and the cavity length can be effectively shortened, so that the laser can run in a single-longitudinal-mode state, and the generated laser has good coherence. The D-shaped fiber is used as the body of the resonant cavity, the constraining performance of the resonant cavity on light can be reduced, and part of the transmitted light is leaked from one side to form an evanescent field which is sensitive to external environment changes, so that induction of a specific parameter can be realized.

The invention belongs to the technical field of fiber lasers, and particularly relates to an incoherent super-continuum spectrum light source with controllable spectrum and tunable output power. The incoherent super-continuum spectrum light source comprises a random pulse fiber laser, a single-mode fiber, a double-clad ytterbium-doped / tapered ytterbium-doped fiber amplifier and a highly-nonlinearintermediate infrared soft glass fiber. The incoherent super-continuum spectrum light source can realize three modes of incoherent super-continuum spectrum output such as a near-infrared band or an intermediate infrared band, a visible light-near infrared band or a near infrared-intermediate infrared band and a visible light-intermediate infrared band through selecting different super-continuum generation modules. In addition, through performing combined control on the length of the single-mode fiber, the output power of a pumping source in the double-clad ytterbium-doped / tapered ytterbium-doped fiber amplifier and the length of the highly-nonlinear intermediate infrared soft glass fiber, the incoherent super-continuum spectrum light source not only can realize control on the output spectrum range and shape, but also can realize tunable output power of the super-continuum spectrum under the condition that the output spectrum range and shape are fixed.

The invention belongs to the technical field of trace gas detection, and provides a scattering enhanced gas sensing probe comprising a metal shell, a non-resonant photo-acoustic cavity, a porous scattering medium, a fiber F-P sonic sensor sensitive film, a gold-plated reflector, a photo-acoustic excitation light source incident fiber, a fiber collimator, a fiber F-P sonic sensor detection light source incident fiber, a F-P cavity, an air inlet and an air outlet, wherein the metal shell is detachably connected with one end of the non-resonant photo-acoustic cavity, and the gold-plated reflectoris fixed at the other end of the non-resonant photo-acoustic cavity; the porous scattering medium is filled into the non-resonant photo-acoustic cavity; a groove is formed in one surface of the metalshell and sealed by the fiber F-P sonic sensor sensitive film, and thus the F-P cavity is formed; the metal shell is provided with the fiber F-P sonic sensor detection light source incident fiber andthe photo-acoustic excitation light source incident fiber. The scattering enhanced gas sensing probe can improve the absorption optical distance of the gas, and enhance the detection sensitivity of the trace gas.

The invention discloses a fiber grating wavelength demodulating device based on a saturable absorption fiber. The device comprises a pumping source, a gain fiber, the saturable absorption fiber, a circulator, an annular cavity or linear cavity fiber laser formed by a fiber grating to be measured and a photoelectric detection system used for measuring the repetition frequency of lasers. By measuring the repetition frequency of the lasers, wavelength changes of the fiber grating to be measured are obtained through calculation, and wavelength demodulation is achieved. The fiber grating wavelength demodulating device based on the saturable absorption fiber avoids using spectral analysis equipment and thus lowers the wavelength demodulation cost. Meanwhile, an all-fiber demodulating system is obtained, the demodulating system is made to be small in size, easy to maintain and easy and convenient to use.

Disclosed is a Multi-pass chirped fiber grating pulse broadening device for. The device comprises a wide-spectrum signal source, a 2*2 acoustic optical modulator, an optical fiber circulator, a chirped fiber grating, an optical fiber isolator, gain media, a wavelength division multiplexer, a band-pass filter, a general control trigger signal source, a digital pulse delay generator, a pumping protector and a pumping source. The device has the advantages that pulse broadening of large dispersion measures can be achieved through the short chirped fiber grating, the broadening amount can be adjusted freely by controlling the broadening times through gate signals generated by the digital pulse delay generator, and accordingly, the cost is reduced effectively, all-fiber is achieved, the structure is compact, and energy losses in a broadening process are compensated.

The invention relates to a nanosecond pulse fiber laser with a circle structure, belonging to the technical field of lasers. The laser mainly comprises a pumping source (1), a WDM (wavelength division multiplexer) (2), a gain fiber (3), a fiber beam splitter (4), an output end (5) of the fiber beam splitter, a first glass sleeve (6), a first auto-focusing lens (7), a saturable absorber (8), a second auto-focusing lens (9), a second glass sleeve (10), a fiber circulator (11), an FBG (fiber Bragg grating) (12), a reflector (13) and a fiber isolator (14). The glass sleeves, the auto-focusing lenses and the saturable absorber are bonded together to form a miniaturized Q-adjusting component, thus realizing the overall fiber of the fiber laser and reducing the interferences from other external factors. The nanosecond pulse fiber laser has the advantages of small volume, low cost, overall fiber, simple structure, wide application prospects and the like.

The invention discloses a cascaded pumping all-optical fiber cable polarization mode-locked laser device, which comprises a cascaded pumping system, a main oscillator loop and a nonlinear optical loopmirror system. By adopting the cascaded pumping all-optical fiber cable polarization mode-locked laser device, mode-locked pulse output is realized without using a space component, and the cascaded pumping all-optical fiber cable polarization mode-locked laser device has the advantages of simple design, compact structure, high stability and high efficiency.

The invention discloses an upconversion single-frequency blue-green optical fiber laser, which comprises a broadband optical fiber Bragg grating, a highly doped fluoride optical fiber, a narrow-band optical fiber Bragg grating, a resonant cavity temperature control module, a wavelength division multiplexer, a pump source and an optical isolator. High-doped fluoride fiber is used as laser gain medium, which is connected with broadband fiber Bragg grating and narrow-band fiber Bragg grating respectively to form single-frequency laser short cavity. Combined with the upconversion luminescence process of high-doped fluoride fiber, the single-frequency blue-green fiber laser output is realized from the resonant cavity. Compared with the traditional semiconductor blue-green laser and the blue-green laser obtained by nonlinear frequency conversion, The invention has the advantages of all optical fiber connection, simple structure, easy maintenance, low cost and high stability, and can be usedfor laser display, underwater communication and optical data storage, and has important application value in the fields of atomic detection, laser spectroscopy, biomedical treatment and the like.

The invention provides a high-sensitivity all-optical-fiber anti-stokes Raman detection system. A light output end of an optical fiber laser device is connected with a first optical fiber and a second optical fiber respectively; a light outgoing end of the first optical fiber is connected with an optical fiber high-pass filter by a non-linear optical fiber; a stokes light output end of the optical fiber high-pass filter is jointly connected with a fourth optical fiber through pump light outgoing ends of a third optical fiber and the second optical fiber; a light outgoing end of the fourth optical fiber sequentially passes through an optical fiber grating filter, an optical fiber bundle and a convex lens to reach an incidence end of a sample; a light reflection end of the sample is connected with a first collection optical fiber and a second collection optical fiber by the optical fiber bundle and the optical fiber grating filter in sequence; a light outgoing end of the first collection optical fiber is connected with a light signal strength detection unit; and a light outgoing end of the second collection optical fiber is connected with a spectral signal detection unit. According to the high-sensitivity all-optical-fiber anti-stokes Raman detection system, the full optical fiberization of a light source and epi-CARS signal detection can be realized, so that the simplification and miniaturization of a high-sensitivity CARS detection system can be realized, and the application range of the CARS detection system is enlarged.

The invention discloses an all-solid-state high-speed rotation measurement system based on an optical fiber structure. Its three sets of orthogonal optical fiber gyroscope modules and optical fiber metering modules share a light source, and three axial optical fiber gyroscope modules and three axial optical fiber gyroscope modules The optical fiber metering modules share a detector respectively, and multiplexing technology is used to extract motion information in three orthogonal directions. The whole system is uniformly controlled by the central processor to realize the fusion of the fiber optic gyroscope module and the fiber optic metering module. The present invention realizes the all-solid-state, all-optical, integration and integration of the entire inertial measurement system, which not only saves resources and costs for the system, reduces power consumption, but also improves the stability and reliability of the system, providing a The upgrade provides strong technical support.

A device for measuring a stimulated brillouin scattering gain spectrum of a low-temperature optical fiber comprises a continuous optical fiber laser device, an optical fiber isolator, a 1*2 optical fiber beam splitter, a doubly clad optical fiber amplifier, an optical fiber circulator, a temperature control system, a monomode optical fiber, a 2*2 port 3dB beam splitter, a band-pass filter, a photoelectric detector and an electrical-graphic analyzer. The optical fiber can be refrigerated in a temperature-controllable manner by using liquid nitrogen, the stimulated brillouin scattering gain spectrum in the optical fiber is measured by using an optical heterodyning detecting technology, and measurement accuracy can be improved. The device can realize all-fiber laser, and is controllable in temperature, compact in structure and high in measurement accuracy.

The utility model provides a device for improving the Signal-to-Noise Ratio of laser. The device for device for improving the Signal-to-Noise Ratio of laser consists of a first polarization controller, a polarizer, and a beam splitter with 1*2 ports, which are fixed in turn in the direction of travel of the beam of light. After the incident beam passes through the beam splitter with the 1*2 ports, the incident beam is split into two beams. One of the beams is used for monitoring, and the other beam is outputted after passing through a non-linear birefringent medium, a second polarization controller and a polarization analyzer. The device for improving the Signal-to-Noise Ratio of laser has the characteristics of easy adjustment, compact structure, the Signal-to-Noise Ratio improved by 10<4>, and full utilization of optical fiber.

An optical fiber smoke sensing temperature fire automatic alarm linkage control system is provided. The system comprises a fire linkage controller, at least one smoke fire alarm controller, and at least one temperature fire alarm controller. The fire linkage controller is in a signal connection with the smoke fire alarm controller and the temperature fire alarm controller by using the optical fiber; the fire linkage controller, the smoke fire alarm controller, and the temperature fire alarm controller are in a signal connection with a manual fire alarm button, a manual fire hydrant button, a linkage control device, and a fire extinguishing controller by using the optical fiber; and the smoke fire alarm controller and the temperature fire alarm controller are in a signal connection with a corresponding fiber-optic smoke-sensed detector and a corresponding fiber-optic temperature-sensed detector by using the optical fiber. According to the design of the present invention, not only the optical fiber technology can be used to build a fire alarm system with a better fire alarm effect, but also high precision, strong safety and a wide control area can be realized.

A long and short laser pulse synchronization device is applicable to high precision time synchronization between short laser pulses and arbitrarily-shaped long laser pulses, and a stable relative time relation between multiple paths of laser pulse signals is realized. Beam splitting is carried out on light outputted by a short laser pulse system by a 1*2 beam splitter, a beam of light obtained through beam splitting sequentially passes through an optical pulse accumulation device, a high-speed photoelectric tube, a fast comparator and a first wideband high speed electric amplifier, and after outputted square wave electrical signals are subjected to shaping of an aperture coupled microstrip line shaping plate and amplification of a second wideband high speed electric amplifier, the signals are inputted to a radio frequency input end of an amplitude modulator. In addition, output light of a long pulse laser enters the amplitude modulator via a second adjustable delay device, and the amplitude modulator outputs shaped light pulses. The relative time jitter between light pulses outputted by the shaped light pulses and the short pulse laser system is 3.5 ps (mean square root, five hours), the repetition frequency can achieve MHz order of magnitude, and the device of the invention has the advantages of compact structure, reliable work, low cost and easy extension.

The invention discloses an ytterbium-doped full-optical-fiber optical frequency comb system and relates to the technical field of frequency comb measurement. The system utilizes an ytterbium-doped full-optical-fiber annular cavity mode-locked laser to achieve mode-locked laser pulse output under the non-linear polarization rotation condition, achieves control chromatic dispersion in a cavity through a first band gap photonic crystal fiber and accordingly reduces in-cavity noise. An ytterbium-doped double-clad optical fiber amplifier is utilized to perform mode-locked laser pulse amplification, and a second first band gap photonic crystal fiber is utilized to achieve compression of mode-locked laser pulse width. Compressed mode-locked laser pulses pass through a tapering photonic crystal fiber welded with an optical fiber compressor to achieve output of an octave super-continuous spectrum. The full-optical-fiber performance of the whole ytterbium-doped full-optical-fiber optical frequency comb system achieves is achieved, repetition frequency and original frequency of an optical frequency comb can be locked, and the stability and portability of the ytterbium-doped optical frequency comb with a full-optical-fiber structure are improved.

The invention discloses a mode-locked fiber laser based on self-phase modulation. The mode-locked fiber laser comprises a wavelength division multiplexer, a semiconductor laser, a gain fiber and a band-pass filter. Laser pulses emitted by the semiconductor laser are coupled into the gain optical fiber through the wavelength division multiplexer. The spectrum is broadened nonlinearly under the action of self-phase modulation, the width of the laser pulse is in positive correlation with the broadened spectrum, the spectrum broadening reaches the filtering range of an optical filter in the band-pass filter so as to improve the transmittance of the optical filter to the spectrum, and a saturable absorption mechanism is formed so as to realize mode locking. The mode-locked fiber laser has the advantages that the structure of the fiber laser is simplified, the monopulse energy of the laser is improved, the spectral width of pulses is increased, the pulse width of the pulses is reduced, and the peak power of the pulses is improved.

The invention relates to a fluorescence detection system and method based on a double-core photonic crystal fiber. A to-be-detected fluorescence sample solution is poured into an air hole of the double-core photonic crystal fiber through a liquid absorption device; one end of the double-core photonic crystal fiber is connected to a spectrometer module, and the other end of the double-core photonic crystal fiber is connected to a laser through a single-mode fiber; a first fiber core in the double-core photonic crystal fiber outputs excitation laser; a second fiber core in the double-core photonic crystal fiber outputs a fluorescence signal; and the fluorescence signal is coupled to a spectrograph module for subsequent analysis. Background laser can be effectively filtered, the micro-fluidic function and the fluorescence excitation enhancing function are achieved, and a good detection effect can be obtained under the condition that only a small number of samples are consumed.

The invention discloses an all-fiber polarizer and a preparation method. According to the polarizer, acting surfaces and a metal film are designed on a double-clad fiber, a stripping area is arranged in the middle of a coating layer of the fiber, two acting surfaces are processed on a cladding corresponding to the stripping area, the acting surfaces are symmetrically distributed on the two sides of a fiber core and are parallel to each other, and a layer of metal film is plated on each acting surface. The preparation method disclosed by the invention comprises the steps of firstly, stripping part of the coating on the coating layer; then grinding the cladding to obtain two acting surfaces which are symmetrical and parallel to each other; secondly, plating a layer of metal film on the two acting surfaces; and finally, packaging a coating layer stripping area by using a glass tube. The all-fiber polarizer provided by the invention can be directly welded with the output end of a polarization-maintaining fiber laser, greatly improves the extinction ratio of polarization-maintaining laser while ensuring the transmission efficiency, can realize laser single-mode transmission, ensures that the light beam quality is not degraded, and has the advantages of simple structure, low cost, capability of realizing all-fiber and the like.

The invention relates to a coupling structure and a packaging method of an SESAM (semiconductor saturable absorber mirror) and an optical fiber. The coupling structure comprises an optical fiber optical path switching device, a plug, an SESAM mounting base and a multi-axis mounting frame, wherein the SESAM mounting base is arranged on the optical fiber optical path switching device; the plug comprises micropores, and the optical fiber passes through the micropores from one end face of the plug to the other end face of the plug. The other end surface of the plug and the mirror surface end of the SESAM7 are sealed in a closed space; the SESAM is mounted on the SESAM mounting base, and the multi-axis mounting frame clamps the SESAM mounting base to adjust the relative distance and angle between the mirror surface end of the SESAM and the other end surface of the plug, so that each working point of the SESAM corresponds to the position of each optical fiber passing through the plug; pointchanging work of the SESAM is achieved through switching of the multiple optical fibers, the utilization rate of the SESAM is increased, the service life of the SESAM is obviously prolonged, and the maintenance cost of the laser is reduced. The coupling mode is simple in structure, feasible in operation, low in cost and compact in size, realizes all-fiber and replaceable points of the SESAM, and is very beneficial to batch production of fiber ultrafast lasers.