Optical fiber amplifier having light collecting layer structure

The invention, which relates to the communication and large-power laser amplification field, discloses an optical fiber amplifier having a light collecting layer structure. The optical fiber amplifier comprises a fiber (4) and a pumping source (5), wherein the fiber (4) is composed of a fiber core (1), a cladding (2), and a light collecting layer (3). The cross section of the light collecting layer (3) is an ellipse that takes a side length as a long axis, wherein the side length belongs to an inscribed regular N-gon shape of an excircle of the cladding of the fiber or to a regular N-gon shape that is in the cladding and is concentric with the fiber; besides, the N is an integer from 4 to 8. A refractive index of the fiber core (1) is 1.4 to 1.8; a refractive index of the cladding (2) is 1.3 to 1.7; a refractive index of the light collecting layer (3) is 1.5 to 1.9. Besides, a diameter of the fiber core (1) is 5 to 8 microns and an outer radius of the fiber is 62.5 to 100 microns. A side ...

Realization method of linetype cavity single polarization dual wavelength optical fiber grating laser

High-power multiband multilayer rare-earth ion-doped ring-core optical fiber amplifier

The invention relates to a high-power multiband multilayer rare-earth ion-doped ring-core optical fiber amplifier which belongs to the field of high-power broadband optical fiber amplifiers, lasers and special optical fibers. The optical fiber amplifier comprises pump light, signal light and an active optical fiber, wherein the active optical fiber adopts N layers of rare-earth ion-doped ring-core optical fibers, the N is not less than 2 and not more than 10, and the pump light is coupled into the active optical fiber to realize multiband signal light amplification. Because the adopted N layers of rare-earth ion-doped ring-core optical fibers exist in a common central cladding region, the pumping efficiency is greatly improved. Relatively to a traditional double-cladding optical fiber amplifier which only can amplify single-band signal light, the optical fiber amplifier realizes multiband signal light amplification. Relatively to a traditional multiband signal light amplifying device, because ...

Big mode field area microstructure optical fiber having flat basis mode field distribution

The invention discloses a large mode field area and microstructural optical fiber with the mode field distribution of a flat base mode, which relates to a microstructural optical fiber and solves the problem of high-precision control for production technology that a traditional large mode field area optical fiber with the mode field distribution of a flat base mode is provided with an ultralow optical core number hole. The microstructural optical fiber is composed of an optical core and a cladding which surrounds the optical core, wherein a core zone is composed of one or seven air hole defects; the cladding is composed of air holes (2) arranged in a triangle period, or fluorine-silica medium cores (4); and a germanium-doped silica medium layer which is provided with a specific radius andrefraction index of inner layers and outer layers is led in the juncture of the fiber core of the microstructural optical fiber and the cladding. The base mode field of the microstructural optical fiber ...

Double greenhouse apparatus of single frequency fiber amplifier for raising stimulated Brillouin scattering threshold

The invention provides a double greenhouse apparatus of a single frequency fiber amplifier for raising stimulated Brillouin scattering threshold, belonging to the high rating narrow linewidth fiber laser and fiber amplifier field. According to the invention, the problems of complex technology, unable reuse of a fiber and small expansion of a fiber in present apparatus are solved. In the apparatus, the opening of the short shaft of a first thin elliptical half pipe (4) and the opening of the short shaft of a second thin elliptical half pipe (5) are positioned in a parallel way, and the first thin elliptical half pipe (4) and the second thin elliptical half pipe (5) are respectively arranged in a first heat insulation box (1) and a second heat insulation box (2). A first temperature controller load (17) and a second controller load (27) are respectively arranged in the first heat insulation box and the second heat insulation box, connecting a first temperature controller (16) and a second ...

Optical fiber of coupling multilayer rare earth blending ring-shaped fiber core with single-mold fiber core

The invention relates to an optical fiber of coupling a multilayer rare earth blending ring-shaped fiber core with a single-mold fiber core, belonging to high-power optical fiber amplifiers, lasers and special fibers; a rare earth blending ion core area (1) is arranged at the center of the optical fiber, a first silicon ring core (21), a first rare earth blending ion ring core (41), ...(N+1)th silicon ring core (2, N+1), and a coating layer (3) are sequentially arranged from inwards to outwards, wherein, N is more than or equal to 2 and is less than or equal to 50; the refractive indexes of the rare earth blending ion core area, the first rare earth blending ion ring core, ...and the Nth rare earth blending ion ring core (4N) are equal, the refractive indexes of the first silicon ring core, ...and the (N+1)th silicon ring core are equal, the refractive indexes of the first silicon ring core (21), ...and the (N+1)th silicon ring core are lower than the refractive indexes of the rare earth ...

Extra-bright single-mold fiber laser with strong-coupled multi-mold rare-earth-doped ring core

The invention discloses an extra-bright single-mold fiber laser with a strong-coupled multi-mold rare-earth-doped ring core. The laser comprises a pumping source and an active fiber, wherein the active fiber includes a single-mold rare-earth-doped fiber core (4), a first silicon annular zone (61), a multi-mold rare-earth-doped ring core (2), a second silicon annular zone (62) and an outer coating layer (3) from inside to outside in sequence; the smallest distance between the surface of the single-mold rare-earth-doped fiber core and the internal surface of the multi-mold rare-earth-doped ring core is less than or equal to 5Mum and more than 1Mum; a first raster (51) and a second raster (52) are written in the two ends of the single-mold rare-earth-doped fiber core; or a high-reflecting film (8) corresponding to the laser light wavelength is plated at one end of the active fiber, and the second raster is written in the single-mold rare-earth-doped fiber core at the other end; or the high-reflecting ...

Large-power multiwaveband multicore optical fiber laser

The invention relates to a large-power multiwaveband multicore optical fiber laser which belongs to large-power broadband optical fiber lasers. All or part of rare-earth ion-doped raster with 100 percent reflection coefficient of an emitting wavelength, which is contained in all fiber cores, is written into all fiber cores of a multi-rare-earth ion-doped multicore double-cladding optical fiber or all or part of rare-earth ion-doped films with 100 percent reflection coefficient of the emitting wavelength, which are contained in all the fiber cores, are plated on the end surface of the multi-rare-earth ion-doped multicore double-cladding optical fiber; all or part of rare-earth ion-doped raster with partial reflection coefficient of the emitting wavelength, which is contained in all the fiber cores, is written into all the fiber cores of the multi-rare-earth ion-doped multicore double-cladding optical fiber or all or part of rare-earth ion-doped films with partial reflection coefficient of ...

Double covered optical fiber side-pumping coupler grating and realization method thereof

Optical fiber of coupling multilayer rare earth blending ring-shaped fiber core with single-mold fiber core

The invention relates to an optical fiber of coupling a multilayer rare earth blending ring-shaped fiber core with a single-mold fiber core, belonging to high-power optical fiber amplifiers, lasers and special fibers; a rare earth blending ion core area (1) is arranged at the center of the optical fiber, a first silicon ring core (21), a first rare earth blending ion ring core (41), ...(N+1)th silicon ring core (2, N+1), and a coating layer (3) are sequentially arranged from inwards to outwards, wherein, N is more than or equal to 2 and is less than or equal to 50; the refractive indexes of the rare earth blending ion core area, the first rare earth blending ion ring core, ...and the Nth rare earth blending ion ring core (4N) are equal, the refractive indexes of the first silicon ring core, ...and the (N+1)th silicon ring core are equal, the refractive indexes of the first silicon ring core (21), ...and the (N+1)th silicon ring core are lower than the refractive indexes of the rare earth ...

Tail fiber coupling output device of laser diode array / surface array

The invention discloses a tail fiber coupling output device of a laser diode array/area array, relates to beam shaping and coupling of a semiconductor laser, and is used for manufacturing a high-efficiency high-power tail fiber output laser diode array/area array. A luminous surface of the laser diode array or area array with fast axis collimation is closely attached with a rectangular or square input end surface of an optical fiber cone; the tail end of the optical fiber cone with the rectangular or square input end surface is positioned on the focus of a first parabolic reflector or the focus of a second parabolic reflector; the first parabolic reflector or the second parabolic reflector are arranged on the focus on one side of a first spherical focusing lens or a second spherical focusing lens respectively; and a single mode optical fiber or a double-coated optical fiber is respectively positioned on the focus on the other side of the first spherical focusing lens or the second spherical ...

Conical coupling long-period optical fiber grating and method of manufacturing same

The invention relates to a tapered coupled long-period fiber grating and a manufacturing method thereof, which are suitable for the fields of optical fiber communication, sensing, microwave photon and so on. The method comprises the following steps: one end of an optical fiber (7) is fixed on a mobile device (1) and the other end of the optical fiber (7) is fixed on a heavy object (6) through a dead pulley (5); the optical fiber is supported into a left optical fiber clamping V-shaped groove (21) and a right optical fiber clamping V-shaped groove (22); after the optical fiber is in the straightening state by the heavy object, the optical fiber is clamped into the left and right optical fiber clamping V-shaped grooves; a coating of the optical fiber between the optical fiber clamping V-shaped grooves is stripped; the coating stripping position is heated to the fusion temperature by an upper heating device (31) and a lower heating device (32); the left optical fiber clamping V-shaped groove ...

Super-luminance single-mode laser for realizing outer cavity coupling between single-mode active fibre core and multi-mode active fibre core

The invention relates to a super-luminance single-mode laser for realizing outer cavity coupling between a single-mode active fibre core and a multi-mode active fibre core, belonging to the field of high-power optical laser and comprising a pumping source and a double-cladding active optical fibre. The double-cladding active optical fibre comprises a single-mode active rare earth doped fibre core (4), a multi-mode active rare earth doped fibre core (6), an inner cladding (2) and an outer cladding (3). A diffraction optical element is arranged at one end of the double-cladding active optical fibre without plating the highly reflective membrane (8) with the laser wavelength; the diffraction optical element consists of a first beam splitter (91), a second beam splitter (92) and a combiner (93); and the working wavelength of the diffraction optical element is the corresponding laser wavelength. The invention realizes outer cavity coupling between the single-mode active rare earth doped fibre ...

Single-mode operated large mold field area multi-mode optical fiber laser

The invention discloses a large-mode-area multimode fiber laser in single-mode operation, and relates to a fiber laser. The fiber laser solves the problems of higher mechanical strength and high-precision control of production process required for a doped multimode fiber. One end of a microstructure fiber (5) of the laser is aligned and connected with the doped multimode fiber (4), and the other end of the microstructure fiber (5) is clung to a high-reflection end dichroic mirror (6) or connected with a fiber grating (8); and the other end of the doped multimode fiber (4) is aligned with an output end dichroic mirror (7) tilting 45 degrees. Pumping light is coupled from the two ends of the laser into the laser. The microstructure fiber (5) has the function of filtering higher-order modes apart from the fundamental mode in the multimode fiber, and an all-fiber integrated fiber laser can be designed, which greatly improves the operation stability of the laser to cause the fiber laser to have ...

Single mode output laser for spiral coupling active doping optical fibre stick

The invention discloses a spiral coupling rare-earth-doped optical-fiber rod single-mode output LASER, comprising a pumping source (1) and a pumping source (2), a single-mode rare-earth-doped optical-fiber (6) and a rare-earth-doped optical-fiber rod. The pumping source (1) pumps the LASER composed of a fiber grating (71), a fiber grating (72) and the single-mode rare-earth-doped optical fiber (6); the pumping source (2) pumps the rare-earth-doped optical-fiber rod, and the fiber grating (71), the fiber grating (72) and the single-mode rare-earth-doped optical-fiber (6) are connected, and placed in the spiral groove prepared on a rare-earth-doped optical-fiber coating (3), wherein, the partial or complete coating of the fiber grating and single-mode rare-earth-doped optical-fiber placed in the groove is removed, and the groove is encapsulated. The two end faces of the rare-earth-doped rod is treated smooth, and by internal strong coupling, the resonance of rare-earth-doped optical-fiber ...

Alloptical fiber non-dispersive adjustable grating attenuator with filtering function

The invention discloses an all-fiber, nondispersive and adjustable fiber grating attenuator with the function of wave filtering, and the attenuator is applicable to the fields of optical fiber communication, optical fiber sensing, traffic information engineering, microwave photonics and the like. The attenuator is composed of a circulator or a coupler, a triangle fiber grating (31), a triangle fiber grating (32) and an adjuster (2), wherein, any one of the two triangle fiber gratings can be tightly adhered to the adjuster; the reflectivity of one triangle fiber grating linearly increases fromshort wavelength to long wavelength; the reflectivity of the other triangle fiber grating linearly increases from the short wavelength to the long wavelength; the narrow bands of the triangle fiber gratings reflect for realizing the function of wave filtering; the two triangle fiber grating are reversely connected for counteracting the dispersion; the adjuster is used for adjusting the triangle fiber ...

Large-effective-area single mode optical fiber amplifier based on change of refractive index distribution of cladding

The invention discloses a large-effective-area single mode optical fiber amplifier based on the change of refractive index distribution of cladding, which is applicable in the field of optical fiber communication. In order to solve the problem that the conventional optical fiber amplifier fails to combine single mold and high power, the laser transmission mode of fiber core is changed by changingthe refractive index distribution of the cladding of the optical fiber in the amplifier, so the signal amplification in a large mold field area is realized under a single mold condition. The concreteprocess comprises the following steps of: corroding and removing the cladding (2) of the optical fiber with solution of hydrofluoric acid and filling with quartz of which the refractive index is bigger than that of the cladding (2) and smaller than that of the fiber core (1) to form a filling area (4), wherein the filling area may be D-shaped, annular, rectangular and spirally coiled. The opticalfiber ...

Method for preparing silver-containing polarized glass

The invention provides a method for preparing silver-containing polarized glass, which belongs to the field of optical fiber communication and photoelectric display. When the silver-containing polarized glass is prepared, the method comprises the following steps: spraying a glass sheet with a layer of SiO2, cutting and grinding the glass sheet to enable micro-grooves to appear on the surface of the glass sheet through an optical mode and photoetching, wherein the width and intervals of photolithographic grooves are both determined by an even-phase mask plate; spraying and attaching silver halide to the micro-grooves; and utilizing plasma technology to manufacture a layer of SiO2 glass material to cover the micro-grooves and grinding the glass sheet again to obtain the silver-containing polarized glass. The method is different from the prior common sol-gel method for manufacturing the silver-containing polarized glass, easy to control process flow, stable in the working performance of products ...

Transmission device generating micro-wave and mm wave by using linear cavity dual-wave optical fiber laser

The invention discloses a device for generating a microwave and a millimeter wave by utilizing linear cavity double wavelength fiber laser. In the invention, active optical fiber (21), (22) is selected, a deviation preserving fiber grating (11) is coupled in the middle part, and broadband fiber gratings (12), (13) are coupled in the other two sides. The reflection spectrums of the broadband fiber gratings are isolated mutually or are provided with a weaker overlapping part. The invention utilizes a coupler to cause pumping light (31), (32) to be coupled into the active optical fiber. The reflection peaks of the two broadband fiber gratings are respectively aligned to the reflection peak of the deviation preserving fiber grating, and each broadband fiber grating forms a resonator only with a the reflection peak in the polarization state of the deviation preserving fiber grating to generate double wavelength laser with ingle polarization. The double wavelength laser is inputted into photodetectors ...

Active optical fiber with characteristics of single-mode output TM01 mode

The invention discloses an active optical fiber with the characteristics of single-mode output TM01 mode and relates to the active optical fiber. The active optical fiber comprises a rare earth-doped ion fiber core (1) and a cladding (4). A non-rare earth-doped ion annular fiber core (2) is arranged between the rare earth-doped ion fiber core (1) and the cladding (4). Axisymmetrically distributedrectangular air holes (3) or a circular air hole array (5) are/is introduced into the non-rare earth-doped ion annular fiber core (2) along the radius direction, the included angle between the adjacent air holes is 360/m degrees, m is larger than 12 and smaller than 30, and the m is an integer. The active optical fiber can solve the problems of requiring to simplify the structure of an optical fiber laser system with the single-mode output TM01 mode and improving the working stability. Finally, the TM01 mode in the optical fiber laser can occupy the dominant position in the mode competition. The ...

Bragg grating sensing demodulation system based on CCD and long-period optical fiber grating

A Bragg grating sensing and demodulating system based on a CCD and long-period fiber grating is characterized in that the side surface of a long-period fiber grating is tightly attached to the surface of a CCD (2); the long-period fiber grating and the CCD are sealed together in an opaque box (3); one end of the long-period fiber grating is connected with a photodetector (4), and the other end is connected with a Bragg grating sensing unit (7); the CCD is electrically connected with a controller (5); the photodetector, the controller and a signal processing unit (6) are electrically connected with each other; the data detected by the photodetector and the data obtained by the CCD controller are transmitted to the signal processing unit together; and the signal processing unit processes the two data to obtain the wavelength drift magnitude of the Bragg grating of the Bragg grating sensing unit. The signal processing unit determines the fluctuation of the optical power of the light source ...

Single mode output laser for spiral coupling active doping optical fibre stick

The invention discloses a spiral coupling rare-earth-doped optical-fiber rod single-mode output LASER, comprising a pumping source (1) and a pumping source (2), a single-mode rare-earth-doped optical-fiber (6) and a rare-earth-doped optical-fiber rod. The pumping source (1) pumps the LASER composed of a fiber grating (71), a fiber grating (72) and the single-mode rare-earth-doped optical fiber (6); the pumping source (2) pumps the rare-earth-doped optical-fiber rod, and the fiber grating (71), the fiber grating (72) and the single-mode rare-earth-doped optical-fiber (6) are connected, and placed in the spiral groove prepared on a rare-earth-doped optical-fiber coating (3), wherein, the partial or complete coating of the fiber grating and single-mode rare-earth-doped optical-fiber placed in the groove is removed, and the groove is encapsulated. The two end faces of the rare-earth-doped rod is treated smooth, and by internal strong coupling, the resonance of rare-earth-doped optical-fiber ...

Optical fiber amplifier having light collecting layer structure

The invention, which relates to the communication and large-power laser amplification field, discloses an optical fiber amplifier having a light collecting layer structure. The optical fiber amplifier comprises a fiber (4) and a pumping source (5), wherein the fiber (4) is composed of a fiber core (1), a cladding (2), and a light collecting layer (3). The cross section of the light collecting layer (3) is an ellipse that takes a side length as a long axis, wherein the side length belongs to an inscribed regular N-gon shape of an excircle of the cladding of the fiber or to a regular N-gon shape that is in the cladding and is concentric with the fiber; besides, the N is an integer from 4 to 8. A refractive index of the fiber core (1) is 1.4 to 1.8; a refractive index of the cladding (2) is 1.3 to 1.7; a refractive index of the light collecting layer (3) is 1.5 to 1.9. Besides, a diameter of the fiber core (1) is 5 to 8 microns and an outer radius of the fiber is 62.5 to 100 microns. A side ...

Tail fiber coupling output device of laser diode array / surface array

The invention discloses a tail fiber coupling output device of a laser diode array/area array, relates to beam shaping and coupling of a semiconductor laser, and is used for manufacturing a high-efficiency high-power tail fiber output laser diode array/area array. A luminous surface of the laser diode array or area array with fast axis collimation is closely attached with a rectangular or square input end surface of an optical fiber cone; the tail end of the optical fiber cone with the rectangular or square input end surface is positioned on the focus of a first parabolic reflector or the focus of a second parabolic reflector; the first parabolic reflector or the second parabolic reflector are arranged on the focus on one side of a first spherical focusing lens or a second spherical focusing lens respectively; and a single mode optical fiber or a double-coated optical fiber is respectively positioned on the focus on the other side of the first spherical focusing lens or the second spherical ...

Big mode field area microstructure optical fiber having flat basis mode field distribution

The invention discloses a large mode field area and microstructural optical fiber with the mode field distribution of a flat base mode, which relates to a microstructural optical fiber and solves the problem of high-precision control for production technology that a traditional large mode field area optical fiber with the mode field distribution of a flat base mode is provided with an ultralow optical core number hole. The microstructural optical fiber is composed of an optical core and a cladding which surrounds the optical core, wherein a core zone is composed of one or seven air hole defects; the cladding is composed of air holes (2) arranged in a triangle period, or fluorine-silica medium cores (4); and a germanium-doped silica medium layer which is provided with a specific radius and refraction index of inner layers and outer layers is led in the juncture of the fiber core of the microstructural optical fiber and the cladding. The base mode field of the microstructural optical fiber ...

Large-effective-area single mode optical fiber amplifier based on change of refractive index distribution of cladding

The invention discloses a large-effective-area single mode optical fiber amplifier based on the change of refractive index distribution of cladding, which is applicable in the field of optical fiber communication. In order to solve the problem that the conventional optical fiber amplifier fails to combine single mold and high power, the laser transmission mode of fiber core is changed by changing the refractive index distribution of the cladding of the optical fiber in the amplifier, so the signal amplification in a large mold field area is realized under a single mold condition. The concrete process comprises the following steps of: corroding and removing the cladding (2) of the optical fiber with solution of hydrofluoric acid and filling with quartz of which the refractive index is bigger than that of the cladding (2) and smaller than that of the fiber core (1) to form a filling area (4), wherein the filling area may be D-shaped, annular, rectangular and spirally coiled. The optical fiber ...

Pulley device for improving stimulated Brillouin scattering threshold value of high-power optical fiber amplifier

The invention relates to a pulley device for improving the stimulated Brillouin scattering threshold value of a high-power optical fiber amplifier, belonging to the filed of a high-power narrow linewidth optical fiber laser and a narrow linewidth optical fiber amplifier. The pulley device for improving the stimulated Brillouin scattering threshold value of the high-power optical fiber amplifier overcomes the defects of the existing device, namely the process is complex, the optical fiber can not be reused, the flexibility of the optical fiber is small, and the like. In the invention, two endsof the oval long shaft of the large hole of an oval conical tube (4) are fixedly connected with one end of a first steel rope (51) and one end of a second steel wire rope (52) respectively, the otherend of the first steel rope (51) and the other end of the second steel wire rope (52) are fixedly connected with a big mass ball (61) through a first pulley (21) and a second pulley (22), two ends ofthe ...

Transmission device generating micro-wave and mm wave by using linear cavity dual-wave optical fiber laser

Multilayer rare earth doped ion ring core fiber and manufacture method thereof

The invention relates to a multilayer rare earth ion ring doped core fiber. The center of the fiber is a silicon core area (1), and rare earth doped ion ring cores from (41) to (4N) are distributed outside the silicon core area (1) from the inside to the outside, wherein N is not less than 2 and not more than 10, and a coating layer (3) is distributed outside the Nth rare earth doped ion ring core (4N); silicon ring cores from (21) to (2K) are distributed among the rare earth doped ion ring cores from (41) to (4N) and the coating layer (3), and K is not less than 0 and not more than N; the refractive indexes of all the earth doped ion ring cores are the same, the refractive indexes of all the silicon ring cores and the silicon core area (1) are the same, and the refractive index of the silicon core area is lower than that of the rare earth doped ion ring cores; and the refractive index of the coating layer is lower than that of the silicon core area. The fiber can amplify multiband signal ...

Alloptical fiber non-dispersive adjustable grating attenuator with filtering function

The invention discloses an all-fiber, nondispersive and adjustable fiber grating attenuator with the function of wave filtering, and the attenuator is applicable to the fields of optical fiber communication, optical fiber sensing, traffic information engineering, microwave photonics and the like. The attenuator is composed of a circulator or a coupler, a triangle fiber grating (31), a triangle fiber grating (32) and an adjuster (2), wherein, any one of the two triangle fiber gratings can be tightly adhered to the adjuster; the reflectivity of one triangle fiber grating linearly increases from short wavelength to long wavelength; the reflectivity of the other triangle fiber grating linearly increases from the short wavelength to the long wavelength; the narrow bands of the triangle fiber gratings reflect for realizing the function of wave filtering; the two triangle fiber grating are reversely connected for counteracting the dispersion; the adjuster is used for adjusting the triangle fiber ...

Pulley device for improving stimulated Brillouin scattering threshold value of high-power optical fiber amplifier

The invention relates to a pulley device for improving the stimulated Brillouin scattering threshold value of a high-power optical fiber amplifier, belonging to the filed of a high-power narrow linewidth optical fiber laser and a narrow linewidth optical fiber amplifier. The pulley device for improving the stimulated Brillouin scattering threshold value of the high-power optical fiber amplifier overcomes the defects of the existing device, namely the process is complex, the optical fiber can not be reused, the flexibility of the optical fiber is small, and the like. In the invention, two ends of the oval long shaft of the large hole of an oval conical tube (4) are fixedly connected with one end of a first steel rope (51) and one end of a second steel wire rope (52) respectively, the other end of the first steel rope (51) and the other end of the second steel wire rope (52) are fixedly connected with a big mass ball (61) through a first pulley (21) and a second pulley (22), two ends of the ...

Realization method of linetype cavity single polarization dual wavelength optical fiber grating laser

The invention relates to a realizing method of linetype cavity single polarization double-wavelength fibre grating laser, in particular to that PMF and two broadband fiber gratings are connected into a suitably-chosen active optical fiber, the reflectance spectrums of the broadband grating are separated with each other. Two reflection peaks are opposite to one of the PMF grating, each grating and one polarization state of the PMF grating compose a resonance cavity, therefore, which can't compose a resonance cavity, each cavity is separated. The double-wavelength laser of stable single polarization can be output at the output end of the linetype cavity. Comparing with the double-wavelength laser, the invention can realize stable single polarization state output more easily, which makes the variance in length and other characters of the active optical fiber won't lead to the substantive effect of single polarization double-wavelength laser. The invention is less affected by the environment ...

Active optical fiber with characteristics of single-mode output TM01 mode

The invention discloses an active optical fiber with the characteristics of single-mode output TM01 mode and relates to the active optical fiber. The active optical fiber comprises a rare earth-doped ion fiber core (1) and a cladding (4). A non-rare earth-doped ion annular fiber core (2) is arranged between the rare earth-doped ion fiber core (1) and the cladding (4). Axisymmetrically distributed rectangular air holes (3) or a circular air hole array (5) are/is introduced into the non-rare earth-doped ion annular fiber core (2) along the radius direction, the included angle between the adjacent air holes is 360/m degrees, m is larger than 12 and smaller than 30, and the m is an integer. The active optical fiber can solve the problems of requiring to simplify the structure of an optical fiber laser system with the single-mode output TM01 mode and improving the working stability. Finally, the TM01 mode in the optical fiber laser can occupy the dominant position in the mode competition. The ...