CN103869507A

CN103869507A - Faraday Rotator and Isolator

Info

Publication number: CN103869507A
Application number: CN201310145605.5A
Authority: CN
Inventors: 蒋仕彬; 耿纪宏; 姜卓; 罗涛
Original assignee: Advalue Photonics Inc
Current assignee: Advalue Photonics Inc
Priority date: 2012-12-07
Filing date: 2013-04-24
Publication date: 2014-06-18
Anticipated expiration: 2033-04-24
Also published as: CN103869507B

Abstract

An all-fiber Faraday rotator and isolator is presented. The device has a multi-component glass optical fiber having a core having a first doping concentration of 55%-85% (wt./wt.) of a first rare-earth oxide and a cladding having a section doping concentration of 55%-85% (wt./wt.) of a second rare-earth oxide, where the first rare-earth oxide and the second rare earth oxide are one or more of Pr2O3, Nd2O3, Pm2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, La2O3, Ga2O3, Ce2O3, and Lu2O3, and where the refractive index of the cladding is lower than a refractive index of the core. The fiber optic device further includes multiple magnetic cells each formed to include a bore extending there through, where the fiber is disposed in the bore of one of the magnetic cells.

Description

Faraday rotator and isolator

Cross

The application is the U.S. Patent application No.13/172 submitting on June 29th, 2011, 623, title is the part continuation application of " All Fiber Optical Isolator ", US No.13/172, 623 is the U.S. Patent application No.12/778 that submit on May 12nd, 2010, 712, title is the part continuation application of " Highly Rare-Earth Doped Fiber Array ", US No.12/778, 712 is the U.S. Patent application No.12/628 that submit on Dec 1st, 2009, 914, title is the part continuation application of " Highly Rare Earth Doped Fiber ".The application, according to 35U.S.C. § 120, requires the right of priority based on aforementioned application, and the content of each application is incorporated in herein by quoting in full, for all objects.

About the research of federation's patronage or the statement of exploitation

The present invention is No.FA9451-12-D-081 as agreed, under government supports, completes.Government has some right in the present invention.

Technical field

The present invention relates to the Faraday rotator based on optical fiber, relate in particular to the Faraday rotator, fibre optic isolater and the fiber polarization rotator that utilize high rare earth element doped fiber.

Background technology

Faraday rotation, or Faraday effect, be a kind of magneto-optic phenomena, it is as interactional result between Light in Medium and magnetic field, the polarization vector that causes light wave rotates to an angle, this angle linearly ratio in the intensity of the magnetic-field component of the direction of propagation conllinear of light.For example, Faraday effect causes leftly to be propagated with slightly different speed with right circular polarization light wave, a kind of character that is called circular birefringence.Given linear polarization vector can be represented as the synthetic of two circular component, and Faraday effect is applied to the relative phase shift effect of bringing out on the light wave of linear polarization, is the orientation rotation that makes the linear polarization vector of light wave.

The experience angle of the linear polarization Vector Rotation of light wave, provided by β=VBd, here β is the anglec of rotation (take radian as unit), V is Wei Erdai (Verdet) constant of the material that passes through of light wave propagation, B is the magnetic density (take tesla as unit) along the direction of propagation, and d is path (take rice as unit).The intensity of the Faraday effect of Verdet constant reflection certain material.Verdet constant can be positive or negative, in the time that the direction of propagation is parallel with magnetic field, is the positive Verdet constant corresponding to counter rotation.Verdet constant is extremely little and relevant with wavelength to most materials.Conventionally, light wavelength is longer, and Verdet constant is less.Should see, the angle that rotation needs can, in the time that the material by high Verdet constant is propagated, obtain in shorter distance.

Faraday effect allows the structure of Faraday rotator, and Faraday rotator is the critical piece of faraday isolator, and faraday isolator is a kind of the device along a direction transmitted light.Relevant Faraday rotator and faraday isolator are the devices of bulk, independent application, can not be applicable to well optics integrated (such as, for example, with based on waveguide or the component integration based on optical fiber), and, in the time being integrated in integrated optics system, requiring to carry out Free Space Optics coupling with the miscellaneous part of this integrated system, thereby limit the degree of this system miniaturization and cause coupling loss.

Summary of the invention

In one embodiment, a kind of full optical fiber Faraday rotator and isolator are presented.This device has multicomponent glass optical fiber, this glass optical fiber has fibre core and covering, this fibre core has the 55%-85%(w/w of the first rare-earth oxide) the first doping content, this covering has the 55%-85%(w/w of the second rare-earth oxide) the second doping content, here this first rare-earth oxide and the second rare-earth oxide is following one or more: Pr ₂o ₃, Nd ₂o ₃, Pm ₂o ₃, Sm ₂o ₃, Eu ₂o ₃, Gd ₂o ₃, Tb ₂o ₃, Dy ₂o ₃, Ho ₂o ₃, Er ₂o ₃, Tm ₂o ₃, Yb ₂o ₃, La ₂o ₃, Ga ₂o ₃, Ce ₂o ₃and Lu ₂o ₃, and the refractive index of covering is less than the refractive index of fibre core here.This fiber device also comprises multiple magnetic elements, and each formation comprises the hole that perforation magnetic element stretches, and this optical fiber is placed in the hole of one of the plurality of magnetic element here.

In another embodiment, a kind of fiber device with the light path that there is no free space region is presented.This device comprises the first and second multicomponent glass optical fiber, respectively there are fibre core and covering, this fibre core has the 55%-85%(w/w of the first rare-earth oxide) the first doping content, this covering has the 55%-85%(w/w of the second rare-earth oxide) the second doping content, here this first rare-earth oxide and the second rare-earth oxide, is selected from a group of following composition: Pr ₂o ₃, Nd ₂o ₃, Pm ₂o ₃, Sm ₂o ₃, Eu ₂o ₃, Gd ₂o ₃, Tb ₂o ₃, Dy ₂o ₃, Ho ₂o ₃, Er ₂o ₃, Tm ₂o ₃, Yb ₂o ₃, La ₂o ₃, Ga ₂o ₃, Ce ₂o ₃and Lu ₂o ₃; And the refractive index of covering is less than the refractive index of fibre core.This device also comprises multiple magnetic elements, and each formation comprises the hole that perforation magnetic element stretches, and this first optical fiber is placed in the hole of a magnetic element here, and this second optical fiber is placed in the hole of another magnetic element.

In another embodiment again, be a kind ofly presented for the method that operates the fiber device with the light path that there is no free space region.The fiber device that the method comprises by having the light path that there is no free space region sends light.The fiber device that this is used, include the multicomponent glass optical fiber of fibre core and covering, this fibre core has the 55%-85%(w/w of the first rare-earth oxide) the first doping content, this covering has the 55%-85%(w/w of the second rare-earth oxide) the second doping content, here this first rare-earth oxide and the second rare-earth oxide is following one or more: Pr ₂o ₃, Nd ₂o ₃, Pm ₂o ₃, Sm ₂o ₃, Eu ₂o ₃, Gd ₂o ₃, Tb ₂o ₃, Dy ₂o ₃, Ho ₂o ₃, Er ₂o ₃, Tm ₂o ₃, Yb ₂o ₃, La ₂o ₃, Ga ₂o ₃, Ce ₂o ₃and Lu ₂o ₃, and the refractive index of covering is less than the refractive index of fibre core here.This fiber device also comprises multiple magnetic elements, and each formation comprises the hole that perforation magnetic element stretches, and this optical fiber is placed in the hole of one of this magnetic element here.

In some embodiment of foregoing embodiments, the plurality of magnetic element is placed like this, makes each have identical magnetic orientation.In another embodiment again, magnetic element is placed like this, makes them have contrary magnetic orientation.In a further embodiment, magnetic element is placed like this, make some have identical magnetic orientation, and other has contrary magnetic orientation.

Accompanying drawing explanation

From the detailed description of elucidated hereinafter, when in the time that accompanying drawing is combined, embodiment of the present invention will become more apparent, and in accompanying drawing, identical unit has identical reference number.

Figure 1A is the schematic diagram of exemplary prior art free space farad isolator;

Figure 1B is the xsect see-through view of exemplary prior art Faraday rotator;

Fig. 2 is the schematic diagram that exemplary prior art has the free space farad isolator of fiber pigtail;

Fig. 3 draws embodiments of the invention;

Fig. 4 is the transmission spectrum curve figure of terbium doped glass;

Fig. 5 signal draws other embodiment of the present invention;

Fig. 6 is the curve map corresponding to the Distribution of Magnetic Field of Fig. 5 embodiment;

Fig. 7 is the viewgraph of cross-section for the exemplary high rare earth element doped fiber of the embodiment of the present invention;

Fig. 8,9,10,11 and 12 draws each different embodiment of the present invention;

Figure 13 signal shows an alternative embodiment of the invention;

Figure 14 and 15 illustrates the performance of polarization maintaining optical fibre splitter/combiner;

Figure 16, by see-through view, describes the another embodiment of the present invention of the splitter/combiner of utilizing Figure 14 and 15;

Figure 17 A and 17B signal draw other embodiment of the present invention;

Figure 18 A, 18B and 18C schematically illustrate the possible magnetic orientation of magnetic element of the present invention;

Figure 18 D schematically illustrates the xsect of the magnetic element using in the present invention;

Figure 19 A and 19B are the signal legends according to Faraday rotator of the present invention; With

Figure 20 is the signal legend according to faraday isolator of the present invention.

Embodiment

Embodiment suggestion is used multiple magnets in the Faraday rotator of many segmentations.Spread all over instructions below, the present invention is described with reference to specific embodiment and relevant figure, and in figure, identical reference number represents same or similar unit.In whole instructions, relevant " embodiment ", " a certain embodiment " or similarly statement, refer to special characteristic, structure or the characteristic described in conjunction with this embodiment, is comprised at least one embodiment of the present invention.Therefore, the appearance of term " in one embodiment ", " in a certain embodiment " or similar statement, in whole instructions, can, but not necessarily all refer to this identical embodiment.

Feature of the present invention, structure or the characteristic described, can be combined in one or more embodiments in any suitable way.In the following description, some concrete details are enumerated to provide the detailed understanding to the embodiment of the present invention.But association area those skilled in the art will recognize, the present invention can be without these one or more details, or are implemented with additive method, parts, material etc.Under other situations, well-known structure, material or operation are not illustrated or describe in detail, the each aspect of the present invention of discussing with obstruction free.

Optical isolator is the device that allows light only to send along a direction.Faraday isolator is the particular type that adopts the optical isolator of Faraday rotator, and this Faraday rotator is a kind of magneto-optical device, and it changes the polarisation of light that passes through the medium that is exposed to magnetic field.

Faraday rotator is relevant with polarization, and comprises and be clipped in two Faraday rotation apparatuses between optical polarizator.The simple legend of the operation of faraday isolator, illustrate with reference to Figure 1A, in figure, draw the common embodiment of faraday isolator 100, this faraday isolator 100 adopts free space farad spinner device 104(to comprise element 104a, for setting up the magnetic field that connects this element, and the material 104b that has high Verdet constant suitably selecting) and have the input of the axis of homology separately and output line polarizer 108 and 112(like this expression be the direction of propagation forward of reference light, z-axle), this axis of homology illustrates with

arrow

108a, 112a.

Input light 120 has the part 116 of the linear polarization that is parallel to vector 108a, by after input polarization device 108, is coupled into this spinner device 104 in transmission.This Faraday rotator 104 makes conventionally rotation 45 degree of polarization vector of light 116, and makes to export light 122 and be transmitted to output polarization device (also claiming analyzer) 112.Light 112 has the polarized component with axis of homology 112a conllinear, as light 124 outgoing in the output of polarizer 112.The light beam that any (, edge-z direction) in opposite direction propagated, the light of for example retroeflection, in the time that it transmits by Faraday rotator 104 for the second time, rotate again in addition 45 (45) degree, thereby have the polarization vector perpendicular to the axis of homology of polarizer 108, from spinner 104 outgoing.Therefore, polarizer 108 stops the light of retroeflection.When being aligned to, the polarization vector of input light 120 is parallel to axis of homology 108a, and when this axis of homology 112a be aligned to be parallel to rotating of light 122 polarization vector time, be minimized from the decay of Faraday rotator 104 outgoing, light propagating by this faraday isolator 100.

Conventionally, Faraday rotator, such as Faraday rotation apparatus 104, comprises terbium gallium garnet (TGG) crystal being inserted in magnetic tube (the unit 104a of Figure 1A), or terbium doped glass (the unit 104b of Figure 1A).Terbium gallium garnet (TGG) is one of the highest Verdet constant of have on 1064nm-40rad/Tm.

Know, the magnetic density of magnetic tube 104 should be enough strong, produces 45 (45) degree polarizations rotations with convenient light while transmitting by Faraday rotator 104.In some common embodiment, this magnetic tube 104a is made up of ferromagnetic material, although other association areas adopt the pipe that is exposed to any material in magnetic field.

As mentioned above, commercial available faraday isolator, is free space device, and light is wherein before being coupled into Faraday rotator, and transmission is by the district of free space.In brief, free space isolator, such as the conventional faraday isolator 100 of Figure 1A, has free space that its parts are separated.Another example shown in Fig. 2, provide the schematic diagram about the another kind of free space farad isolator in field, it by coupling optical device 208 from input optical fibre 210 introduce (intake) input light 120, and by optical devices 212 light 124 be outwards coupled (outcouple) enter output optical fibre parts 220.This what is called has the conventional bulk free space farad isolator device 100 of fiber pigtail, is used to promote the optical coupled between device 100 and integrated optics system part (not shown).Figure 1B illustrates the exemplary Faraday rotator about field by xsect, such as the skeleton view of the device 104 of Figure 1A and 2.

The development of fibre optic isolater, the recent progress aspect high-capacity optical fiber laser has become conclusive.Produce the fiber laser up to ten (10) kilowatts of output powers, be demonstrated, can realize the new application of broad range such as comprising laser bonding, cut, laser drill and military defense application.Even if these fiber lasers are successfully introduced in industry, but due to the restriction of current available optical isolator, their many operation potentiality not yet realize.At present, free space has the isolator of fiber pigtail, such as the isolator of describing in Fig. 2, is used.These free space isolators are introduced to larger optical system, require various accurate operation (such as for example, being coupled again of fibre-optic terminus, lens alignment and the light from fiber laser source to optical fiber), each of these operations, the overall performance of reduction fiber laser.The not only use of free space isolator, make the Power Limitation of fiber laser in about 200W, but also soundness and the reliability of reduction whole system, soundness and reliability are two major advantages that are better than free space solid-state laser that fiber laser provides.Embodiments of the invention come from the optical isolator of having realized as full optical fiber components device, there is no the light path of free space, not only by allowing user to utilize the full spectrum operating characteristic of this fiber laser, be convenient to the use of this isolator with fiber laser source, but also greatly reduce production costs and the probability of malfunction of the full-optical-fiber laser system that obtains the two.The single magnetic tube using with current known system is contrary, by using multistage magnetic material, can reach the further reduction of manufacturing cost and isolator weight.

About field discloses the Faraday rotation apparatus based on optical fiber, or openly do not adopt the faraday isolator system of this Faraday rotation apparatus based on optical fiber.This may be because the fact below causes: with the fiber unit of rare earth material doping, make habitually doping content in the magnitude of several percentage by weights or even lower, this is corresponding to low Verdet constant.For example, 2%(weight) the have an appointment Verdet constant of 1rad/Tm of the silica glass of doping.Adopt the Faraday rotation apparatus of this optical fiber components, before the rotation of the linear polarization vector of the light being guided by this optical fiber components reaches 45 degree, will require this optical fiber components long terrifically, the magnitude of approximately a meter.Therefore, make the performance of such spinner effective, the size of desired magnet unit and weight are of a high price and operate upper infeasible.Completely contradict with relevant field, the optical fiber components that the present invention adopts, is to be greater than 55%(weight) the rare earth material doped in concentrations profiled that enlarges markedly.In certain embodiments, this doping content is greater than 65%(weight).In other embodiments, this doping content is greater than 70%(weight).In specific embodiment, this doping content is in 55%-85%(weight) between.The doping content that these are high, guarantees to obtain the Verdet constant of 30rad/Tm or about 30rad/Tm, is conducive to make the Faraday rotator entirety based on optical fiber in the magnitude of 5cm.

Embodiments of the invention employing or single mode or multimode optical fiber, this optical fiber adulterates with rare earth material, in the structure of Faraday rotator unit.In one embodiment, this Faraday rotator based on optical fiber and polarization unit (below also the claiming fibre optic polarizer) welding based on optical fiber, to form full fibre optic isolater system.As known in the art, welding is to use thermal treatment, pass through the light of the first optical fiber components by transmission, without transmission by free space with minimum optical loss (, scattering on the position of this joint and reflection quilt optimization) this mode that enters the second optical fiber components, be conducive to the end-to-end conllinear of two optical fiber components integrated.In a specific embodiment, the power input of Faraday rotator unit is to be greater than 100 watts.In addition, embodiments of the invention are realized complete optical fiber polarization unit, and in the time being combined with full optical fiber Faraday rotator embodiment, this complete optical fiber polarization unit provides a kind of full fibre optic isolater system of novelty.Further, these embodiment adopt the multiple magnets in various layout, to set up a kind of full optical fiber Faraday rotator and isolator of Multi sectional.

Forward now Fig. 3 to, this illustrates the embodiment 300 of full fibre optic isolater device, propagate run into order along z-axle by this device 300 by light, comprise: the first polarizer 302 based on optical fiber, contain be placed in magnetic element 306a(and be for example made into tubular) in polarizer 310 based on optical fiber of the Faraday rotator 306 and second of optical fiber components 306b.The end of this optical fiber components 306b, with the corresponding end welding (as shown in optical fiber

fusion welding point

320a and 320b) of

polarizer

302 and 310, thereby sets up the device based on full optical fiber.The optical fiber components 306 using in Faraday rotator 306, with such as Pr ₂o ₃, Nd ₂o ₃, Pm ₂o ₃, Sm ₂o ₃, Eu ₂o ₃, Gd ₂o ₃, Tb ₂o ₃, Dy ₂o ₃, Ho ₂o ₃, Er ₂o ₃, Tm ₂o ₃, Yb ₂o ₃, La ₂o ₃, Ga ₂o ₃, Ce ₂o ₃and Lu ₂o ₃in rare-earth oxide doping one of at least.

In a specific embodiment, these parts 306b comprises terbium doped glass.Fig. 4 draws the Tb with 55 percentage by weights ₂o ₃the transmitted spectrum of the glass of doping, this figure shows, although Tb ₂o ₃the Verdet constant presenting is the highest, but also absorbs light near the spectral region of this material 1.5 microns and 2 microns in the middle of those corresponding rare-earth oxides.

Another adopts the embodiment of the Faraday rotator 510 of full fibre optic isolater (not shown) of the present invention, shown in Figure 5.Here, the light of propagating by this embodiment, the angle of the Faraday rotation of its polarization vector, by adopting corresponding glass material to have two auxiliary optical fiber components of contrary sign Verdet constant to be increased.The optical fiber components 510b being made up of the first glass material, is used as the parts of Faraday rotator 510 in magnetic element 510b inside.By Second Type glass material (or, change kind of a mode, by different second and the 3rd glass types)

optical fiber components

516 and 520 made, be placed on respectively in the input and output of Faraday rotator 506, and for example, through welding, by as the crow flies, (end-to-end) is integrated, to set up compound unbroken optical-fibre channel that optical fiber 516,510b and 520 combine successively that comprises.The glass material of each

optical fiber components

516 and 520 has a kind of Verdet constant of symbol, and the glass material of optical fiber components 510b has the Verdet constant of distinct symbols.For example, the glass of magnetic tube 510a inner fiber parts 510b, have negative Verdet constant, and the glass material of

parts

516 and 520 has positive Verdet constant.In a specific embodiment, there is the

optical fiber components

516 and 520 of positive Verdet constant, with Yb ₂o ₃, Sm ₂o ₃, Gd ₂o ₃and/or Tm ₂o ₃in one of at least doping, and have the optical fiber components 510b of negative Verdet constant with Tb ₂o ₃doping.Fig. 6 depicts the Distribution of Magnetic Field of the full fibre optic isolater of Fig. 5.

It should be known that the embodiment that the symbol of Verdet constant is reversed (for example, the fiber optic materials in element 610a has positive Verdet constant, and optical fiber components outside element 610a has negative Verdet constant), also within the scope of the invention.

Referring again to Fig. 3, in one embodiment, the material of the optical fiber components 306b using in Faraday rotator 306 is with La ₂o ₃, Ga ₂o ₃, Yb ₂o ₃and Ce ₂o ₃in one of at least doping.Preferably, the fiber laser with using together with the embodiment of such Faraday rotator, operates near near the wavelength 1.5 microns or 2 microns.

Referring again to Fig. 3, in another relevant embodiment, this optical fiber components 306b comprises multicomponent glass.Specifically, fibre core and/or the covering of such multicomponent glass optical fiber 306b, for example, can contain silicate glass, germanate glass, phosphate glass, borate glass, tellurite glasses, bismuth glass and/or aluminate glass.In addition or in addition, the multicomponent glass of optical fiber components 306, can comprise glass network former (network former), intermediate (intermediate) and modifier (modifier).In certain embodiments, the network structure of glass comprises the atom that can significantly change some type of glass property.Kation can play network modifier, destroys the continuity of network, or plays organizator, contributes to the formation of network.Network former has the quantivalency that is more than or equal to three and the coordination number that is not more than four (coordination number).Network intermediate has lower quantivalency and higher coordination number than Network former.In one embodiment, one or more glass network formers of the multicomponent glass of Fig. 3 optical fiber components 306b, comprise SiO ₂, GeO ₂, P ₂o ₅, B ₂o ₃, TeO ₂, Bi ₂o ₃and Al ₂o ₃in one of at least.

Table 1

Composition	SiO ₂	Al ₂O ₃	B ₂O ₃	CeO ₂	Tb ₂O ₃
						wt%	9.9	0.9	7.4	0.1	72.7
?	?	?	?	?	?
						Composition	SiO ₂	Al ₂O ₃	B ₂O ₃	CeO ₂	Tb ₂O ₃
wt%	13.3	13.9	10.7	0	62.2
						?	?	?	?	?	?
Composition	SiO ₂	Al ₂O ₃	B ₂O ₃	CeO ₂	Tb ₂O ₃
						wt%	12.2	13.3	10	0	64.5
?	?	?	?	?	?
						Composition	SiO ₂	Al ₂O ₃	B ₂O ₃	CeO ₂	Yb ₂O ₃
wt%	14.8	16.5	10.3	0.1	58.3
						?	?	?	?	?	?
Composition	SiO ₂	Al ₂O ₃	B ₂O ₃	CeO ₂	Er ₂O ₃
						wt%	15.1	16.8	10.5	0.1	57.6
?	?	?	?	?	?
						Composition	SiO ₂	Al ₂O ₃	B ₂O ₃	CeO ₂	Yb ₂O ₃
wt%	16	17.8	11.1	0.1	55

Table 1 provides the non-limitative example of the glass of terbium doped silicate glass, erbium doping and the silicate glass of ytterbium doping, and they can be for embodiments of the invention.

Forward now Fig. 7 to, this is the viewgraph of cross-section of the preform of the high rare earth element doping of the exemplary optical fiber components for the manufacture of Faraday rotator of the present invention (such as the parts 306b of Fig. 3), and the glass fibers plug 716 being surrounded by glass-clad pipe 720 is shown on figure.The external diameter of fibre core 716 is so identical with the internal diameter of covering 720, so that between fibre core and covering, there is no blank or gap.The present invention is based on the optical fiber components of the Faraday rotator embodiment of optical fiber, is to use rod-in-tube optical fiber drawing technology (rod-in-tube fiber drawing technique) to manufacture.The glass that this glass of fiber core rod 716 is adulterated by bulk high rare earth element gets out, and the outside surface of this glass of fiber core rod 716 is polished high surface quality.This cladding glass pipe 720 is made up a little less than the rare earth doped glass of the refractive index of rod 716 of another piece refractive index.Interior and the outside surface of cladding glass pipe 720 is polished high surface quality.Afterwards, rod 716 is put in glass tube 720, and this two combination is thereafter heated, until the contraction around this rod of this pipe, after be the fibre-optical drawing program of knowing.

Fig. 8 draws the embodiment 800 that adopts spacer array, and wherein each isolator builds according to embodiments of the invention.As shown in the figure, array 800 comprises the polarizer 802,804,806,812,814 and 816 based on optical fiber, for example, with fiber unit 822b, the 824b and 826b integrated (, the utilizing welding) as the crow flies that are positioned in the magnetic tube 830a of Faraday rotation apparatus 830.In one embodiment, the internal diameter of magnetic tube 830a is that about 1mm is to about 10mm.In one embodiment, the external diameter of each

optical fiber components

822b, 824b and 826b is about 0.125mm.

In one embodiment,

optical fiber components

822b, 824b and 826b can be made up of the glass with identical rare-earth oxide doping of same type entirely.But in addition, in a different embodiment, these parts are made up of dissimilar glass and are adulterated by different rare-earth oxides.Dissimilar due to what adulterate, in such a different embodiment, these

parts

822b, 824b and 826b can be used on different wavelength.For example, the first optical fiber components is by the light absorbing in concrete spectral bandwidth, and second component is by the light absorbing in different spectral bandwidths.In another embodiment again, that

optical fiber components

822b, 824b and 826b representative are made up of same type glass but with the fiber unit of the variable concentrations doping of given rare-earth oxide.In one embodiment, the polarizer 802,804,806,812,814 and 816 based on optical fiber is the polarizer based on optical fiber of same type entirely.But in general, the optical property of the polarizer 802,804,806,812,814 and 816 based on optical fiber can be different.

Fig. 9 provides the schematic diagram of example system, and this system comprises the faraday isolator array 800 with Fig. 8 of corresponding fiber laser array combination.Fiber laser is a kind of laser instrument, and activation gain media is wherein with rare earth doped optical fiber.As shown in Figure 9, each optical channel of faraday isolator array 800, is arranged to separately to be optically communicated with the fiber laser in corresponding fiber laser 940,942 and 944.Although fiber laser 940,942 and 944 can be identical, in general, they are difference one of aspect following at least: the mode of the wavelength of power stage, work and/or work (such as, for example, pulse width).

Figure 10 provides the schematic diagram of example system, and this system comprises the faraday isolator array 800 of the Fig. 8 optically cooperating with the fiber laser and amplifier of a series of cascades.The fiber laser 1070 that this embodiment 1060 comprises spacer array 800, cascade and amplifier 1072 and 1074.The polarization spin fiber parts 822b of the Faraday rotation apparatus of spacer array 800, is sandwiched between laser instrument 1070 and amplifier 1072 as shown in the figure, and integrated as the crow flies with laser instrument 1070 and amplifier 1072.Amplifier 1072 is optically cooperated with polarization spin fiber parts 824b again.Parts 824b is coupled to amplifier 1074 subsequently again, and integrated as the crow flies with amplifier 1074, and integrated as the crow flies with polarization spin fiber parts 826b by this amplifier 1074.In a specific embodiment, with the interconnected fiber section 1082,1084 and 1086 of each active cell of Figure 10 embodiment, and fiber section 1088,1090 and 1092, there are identical optics and material character with optical fiber components 822b, 824b and 826b respectively.But in addition, these interconnect portion, are different from the polarization spin fiber parts of Faraday rotation apparatus one of aspect at least following: type of glass, dopant material and doping content.In general, make interconnected fiber section 1082,1084,1086,1088, the Verdet constant of 1090 and 1092 material, is different from polarization spin fiber parts 822b, the 824b of Faraday rotation apparatus of this embodiment and the Verdet constant of those materials of 826b.In addition, the symbol of the Verdet constant of interconnected fiber section, can be different from the symbol of those Verdet constants of the polarization spin fiber parts of this Faraday rotation apparatus.

The another kind of schematic diagram of full optical fiber Faraday rotator array 1100, is depicted in Figure 11, and it comprises the

optical fiber components

1104,1106 and 1108 being disposed in magnetic element 1110.Each polarization rotary part of this embodiment, also for example integrated as the crow flies with the corresponding fiber unit outside magnetic element 1110 by welding, and with magnetic element 1110 combinations, be suitable as fiber unit operation, make wherein directed polarisation of light vector rotate by Faraday effect.

Figure 12 describes the illustrative diagram of Faraday rotator array 1200, and it at one end with as the reverberator shown in general reflector element 1222 is optically cooperated.This reflector element is applicable to the light that reflection is propagated along polarization spin fiber parts 1104,1106 and 1108 in the z-direction, and a part for this light is returned backward, enters this Faraday rotator 1200, as shown in arrow 1230.In different embodiment, this general reflector element 1222 can comprise: with the optical fiber components of Faraday rotator as the crow flies integrated optical fiber Bragg raster, be disposed in metal on the output facet of optical fiber components of Faraday rotator coating and/or dielectric coated, optionally physically with the reverberator of the output 1224 independent application that separate or or even their combination.Therefore, should know, although the details of optical coupled does not illustrate between output 1224 and reflector element 1222, but such optical coupled can be with well known in the art, such as for example, use coupling or Butt-coupling (butt-coupling), thin-film deposition or independently any means arrangement of the welding of fiber unit in addition such as the optical unit of lens.Therefore should also be appreciated that inevitable stands for freedom space is not wished in the gap between the output 1224 of Faraday rotator 1200 and this general reflector element 1222.

In one embodiment, the polarization spin fiber parts of Faraday rotator 1200, by making with the same glass material of identical rare-earth oxide doping.But in general, these optical fiber components are by making with the dissimilar glass of different rare-earth oxide doping, in this case, they can be used to operate on different wave length, and this wavelength is selected according to the optical property being defined by the particular type of alloy in these parts.Therefore in general, the different fiber parts of Faraday rotator 1200, can bring into play difference in functionality, and for example, polarization spin fiber parts can absorb the light in concrete spectral hand, and another parts can absorb the light of different wave length.In another embodiment again,

parts

1104,1106 and 1108 utilize same type but with the glass material of the rare-earth oxide doping of dissimilar and/or concentration.

Another embodiment 1400 of full fibre optic isolater system is shown in Figure 13, the embodiment 1410 that it comprises Faraday rotator, this Faraday rotator is as discussion above, contain magnetic element 1410a, such as the pipe of being made by magnetic material, and the optical fiber components 1410b placing in element 1410a and along element 1410a.This optical fiber components is by the material based on rare earth element, to make to the glass of the doping content doping of 85wt% according at least 55wt% of the embodiment of the present invention.These parts 1410b corresponds respectively to every one end of input 1412 and the output 1414 of Faraday rotator 1410 at it, integrated as the crow flies with external polarization parts 1420 and 1424, polarization member 1420 and 1424 one of is at least configured to comprise utilize protects the light beam splitter/combiner of (PM) fiber unit partially.The concept of unpolarized optical fiber light beam shunt, this area is known already, does not discuss in detail at this.Relevant with configuration, unpolarized optical fiber shunt can be pressed multiple spot and arrange to multipoint link, makes to be shunted to N>M autonomous channel by the light wave of M root fiber guides.(form of the simplest unpolarized optical fiber shunt is called as Y-shunt, here M=1, N=2).Unpolarized optical fiber combiner, by the simplest situation, is the optical fiber splitter operating conversely, and makes directed light wave in N autonomous channel, is multiplexed into M<N passage.Completely contradict with it, embodiments of the invention utilize optical fiber beam splitter/combiner, and the operation of this splitter/combiner depends on directed polarisation of light state in this optical fiber components.

Figure 14 and 15 draws the simple X-type optical fiber splitter that adopts PM optical fiber.In general, the embodiment of polarization fiber shunt, is configured to make the component of light wave directed in this optical fiber, spatially separates according to this directed wave polarization content, and the directed wave component that has orthogonal polarisation state, be coupled into the different branches of this shunt.For example, be coupled into the light wave 1502 of the given polarization type (schematically illustrating with arrow 1506) of a input branch of polarization fiber light beam shunt 1510, tandem portion 1520 along z-direction towards shunt 1510 propagates, this light wave 1502 is separated in this tandem portion 1520, in order that the component 1502c of the ripple 1502 of orthogonal polarisation state 1530c and 1530d is suitably separated with 1502d, enter different output branch c and the d of shunt.It is similar utilizing the operation of the optical fiber beam combiner 1540 of polarization maintaining optical fibre.As shown in figure 15, such combiner is configured to make to be respectively coupled into the c of branch and two directed ripple 1550c and 1550d d, that have corresponding cross polarization 1560c and 1560d of combiner 1540, pool together (or combination), and (combination) light wave that has polarization state 1570, (as shown in the figure, branch a) to be outwards coupled into the selected output branch of this combiner.

As shown in Figure 16 signal, the embodiment 1600 of full fibre optic isolater of the present invention, comprise the faraday components 1610 based on polarization spin fiber, this faraday components 1610 contains rare earth doped optical fiber components 1610b, places along the length of inner tubular magnetic element 1610a.This embodiment 1600 also contains the light beam splitter/combiner parts 1620 and 1630 based on input and output polarization maintaining optical fibre, these parts 1620 and 1630 are integrated as the crow flies with inputing or outputing of corresponding optical fiber components 1610b respectively, in order that form unbroken optical fiber link, optically the A of input optical fibre branch and B are connected to the C of output optical fibre branch and D by rare earth doped parts 1610b.The different branches of splitter/combiner 1620 and 1630 are applicable to guiding the light wave of orthogonal polarisation state.

As the non-limitative example of operation, and in the time that light is propagated forward, the operation of embodiment 1600 is as follows.In the time that the input light wave 1640 of the axle along definite (being illustrated as y-axle) linear polarization is coupled into the A of input branch of the splitter/combiner 1620 based on PM optical fiber, this splitter/combiner 1620 is generally along z-direction, by the 1620a of tandem portion, send this light wave to Faraday rotator 1610.Passing through after Faraday rotator 1610, the polarization vector 1650 of this directed light wave is rotated 45 degree.This directed light wave is coupled into again splitter/combiner 1630, and splitter/combiner 1630 is configured to, the light that becomes k degree polarization with respect to predetermined shaft, send into output branch C, and sends to optics or the system of the C of this branch and its coupling again.Retroeflection enters the C(of this branch generally along illustrated-z direction) any part of light wave, passing through after the 1630a of tandem portion of splitter/combiner 1630, the polarization rotary part 1610b of full optical fiber link of this embodiment 1600 will be entered, and in end 1634 outgoing of the parts 1610b of faraday components 1610, the polarization vector that makes it is rotated to 45 degree in addition again.The light wave of this retroeflection, the state producing on the joint 1634 between parts 1610b and splitter/combiner 1620, orthogonal with the polarization state that supported by the A branch of splitter/combiner 1620.Because the B of branch of splitter/combiner 1620, be configured to guiding and have and the light of the polarization of the polarized orthogonal that supported by the A of branch, so the light wave of retroeflection is outwards coupled by the B of branch.Person skilled in the art it should be known that in fact embodiments of the invention 1600, makes the laser source of the A of branch that is coupled into this embodiment, with the unwanted bulk of optical feedback isolation forming in the reflection downstream of light path.

Should be understood that, the glass basis of the optical fiber components of faraday components of the present invention, with thundering high concentration rare earth element material doping, guarantee by the linear polarization vector of the light of the optical fiber components of this faraday components guiding, at several centimetres or approximate number centimetre (for example, approximately 5 to 10cm), in spread length, complete the rotation of 45 degree or 45 degree left and right.

Of the present invention many-sided, be to adopt multiple magnets to use together with isolator with any disclosed Faraday rotator above.Compared with single magnet or magnetic tube, using multiple magnets to allow to use has than the more magnetic sections of separating of minor diameter of the diameter requiring in single magnet embodiment, thus cumulative volume and the general assembly (TW) of the magnetic part of reduction Faraday rotator or isolator.Therefore, the total magnetic intensity of every volume is increased, cause than in the embodiment of single magnet for reaching the magnetic material still less of the identical anglec of rotation needs and lower cost of manufacture (because of reduction in bulk of magnetic material).The advantage having is again that more the magnet of minor diameter is easier to magnetization than the larger magnet requiring in the embodiment of single magnet.

As what will see, in the time that multiple magnets are used, these sections can arrange by two basic orientations.As shown in Figure 18 A, this magnet can be arranged like this, and opposite magnetic pole is faced with each other.In this arrangement, each magnet has identical magnetic orientation.Otherwise as shown in Figure 18 B, this magnet can be arranged like this, and same pole is faced with each other.In this orientation, each magnet has contrary magnetic orientation.Other possible orientations are the arrangements that are orientated shown in Figure 18 A and 18B.Specifically, some magnets can be arranged like this, these magnetic poles are faced with each other, and other are arranged like this, and opposite magnetic pole is faced with each other.The schematic diagram of such arrangement is shown in Figure 18 C.

As shown in Figure 18 A, 18B and 18C, two, three, four or more magnets can be used.But specifically, in a preferred embodiment, three magnets are used.Have, magnet itself can have identical or different size again, as shown in Figure 18 B.

With reference to figure 18D, in certain embodiments, the magnetic sections of use is the section separating of magnetic tube, and each has xsect 1802.In other embodiments, the magnetic sections of use is not the section separating of magnetic tube, replaces the xsect of rectangle, such as xsect 1804(a) and 1804(b), or square cross section, such as xsect 1806(a)-(d).In other embodiment that also have, there is the magnetic sections of separating of other xsects to be used.Have again, in certain embodiments, have the mixture of the magnet of various varying cross-sections to be used.Therefore, and unrestricted, a part for optical fiber is surrounded by the section of magnetic tube as an example, and another part is had the magnetic sections of square cross section to surround.

So aimed in the magnetic sections of separating, so that the opposite magnetic pole of magnet is faced mutually, under situation as shown in Figure 18 A, there is the Faraday rotation optical fiber of identical sense of rotation, be placed in each magnet, and have the optical fiber of contrary Faraday rotation direction or have the optical fiber (that is, having the optical fiber of the little anglec of rotation under same magnetic field flux density) of very little Verdet constant, be placed between magnet.The schematic diagram of the exemplary embodiment of the Faraday rotator of full fibre optic isolater like this, shown in Figure 19 A.Can see, Faraday rotator 1900 comprises the optical fiber components 1908,1912 and 1916 in magnetic element 1902,1904 and 1906 respectively, and magnetic element is so orientated there, and opposite magnetic pole is faced with each other.Optical fiber components 1908,1912 and 1916, respectively has identical Faraday rotation direction.In certain embodiments, parts 1908,1912 and 1916 respectively comprise same glass material.In other embodiments, optical fiber components 1908,1912 and 1906 comprises different glass materials.In other embodiment that also have, the doping content that optical fiber components 1908,1912 and 1906 is had nothing in common with each other.As described in, the optical fiber components 1910 and 1914 between magnetic sections, respectively has the Faraday rotation direction contrary with optical fiber components 1908,1912 and 1906, or has very little Verdet constant.And unrestricted, in certain embodiments, optical fiber components 1908,1912 and 1906 comprises the optical fiber of Tb doping as an example, and optical fiber components 1910 and 1914 is undoped optical fiber (thereby having very little Verdet constant).In addition, and unrestricted, optical fiber components 1910 and 1914 is the optical fiber of La doping as an example, and they have the sense of rotation contrary with the optical fiber components 1908,1912 and 1906 of Tb doping.

For Figure 19 A illustrated embodiment,

magnetic element

1902,1904 and 1906 must be separated by a distance d, otherwise

optical fiber components

1908,1912 and 1916 magnetic field intensity around will be lowered.In certain embodiments, this distance is the half of magnetic element length.In other embodiments, be greater than or less than the half of magnetic element length apart from d.In other embodiment of two or more magnetic elements of use that also have, the distance between two elements can change.

The magnetic sections of separating is therein aimed at like this, the same pole of magnet is faced with each other, in embodiment as shown in Figure 18 B, have the Faraday rotation optical fiber of high Verdet constant to be placed in the magnetic sections of, and section placed in the middle have the optical fiber of contrary Faraday rotation direction or very little Verdet constant.The embodiment of the Faraday rotator of full fibre optic isolater like this, shown in Figure 19 B.As seen in Figure 19 B, Faraday rotator 1920 comprises the

optical fiber components

1928,1932 and 1934 in

magnetic element

1922,1924 and 1926 respectively, and wherein magnetic element is so orientated, and same pole is faced with each other.In the embodiment shown in this,

optical fiber components

1928 and 1934 has high Verdet constant and identical Faraday rotation direction.In certain embodiments,

optical fiber components

1928 and 1934 comprises same glass material.In other embodiments,

optical fiber components

1928 and 1934 comprises different glass material.In other embodiment that also have,

optical fiber components

1928 and 1934 has different doping contents.

Contrary with Figure 19 A illustrated embodiment, in certain embodiments, the optical fiber components 1932 of Faraday rotator 1920 will have the Faraday rotation direction contrary with optical fiber components 1928 and 1934.In other embodiments, optical fiber components 1932 has very little Verdet constant.

Although the embodiment that Figure 19 B shows, is so described as the optical fiber that has high Verdet constant, be first and the 3rd magnetic element be in

element

1922 and 1926, in other embodiments, the situation of turning around can be implemented.More particularly, in other embodiments, the optical fiber in the second element can have very high Verdet constant, and first and the 3rd the optical fiber in magnetic element, can have low-down Verdet constant or contrary Faraday rotation direction.In such embodiments, this magnetic element can have the larger diameter of diameter requiring than Figure 19 B illustrated embodiment, because only have a magnet section to cause the rotation needing.

As magnetic element in Figure 19 B by be orientated, make in embodiment that same pole faces with each other, magnetic element can, by distance of separation d, maybe can be forced to direct contact.In a rear situation, because repulsive force, magnet need to use screw, adhesives or other measures in position.The advantage that Figure 19 B illustrated embodiment is better than Figure 19 A embodiment is that the interval between magnet can be as much as possible little.This close contact can strengthen magnetic field in the magnet of two connections.In addition, the whole physical length of Faraday rotator will be less, and this is favourable to many application.

Respectively there is the Faraday rotator of three

magnetic elements

1900 and 1920 although shown, it should be known that this is not mean that for clarity restriction.In each embodiment, more than or be less than three magnetic elements and can both be used.In magnetic element is arranged to embodiment that same pole faces with each other, such as the embodiment with Faraday rotator 1920, preferably use the magnetic element of odd number.

To the layout shown in Figure 19 A or Figure 19 B, although magnetic element is for clarity, is depicted as formed objects and has had identical cross-section diameter, this point does not wish to become restriction.In certain embodiments, there is the magnetic sections of separating of different length or varying cross-section diameter to be used.In addition, the magnetic element of use can be identical magnetic material, can be also different magnetic materials.

In certain embodiments,

Faraday rotator

1900 or 1920 two ends, are also connected with the polarizer based on optical fiber, to form faraday isolator.The schematic diagram of embodiment that uses like this Faraday rotator 1900 draws in Figure 20, and wherein the polarizer 2002 based on optical fiber is connected to the first end of Faraday rotator 1900, and polarizer 2004 based on optical fiber is connected to the other end.As previously described embodiment,

optical fiber components

1908 and 1916 and the corresponding end welding (as by optical fiber fusion welding point 2006(a) of

polarizer

2002 and 2004 and 2006(b) as shown in signal), set up thus the device based on full optical fiber.

The present invention is not departing under spirit of the present invention or essential characteristics, can be implemented by other concrete forms.The embodiment of having described, it is illustrative and unrestricted can being considered in all respects.Therefore, scope of the present invention is by appended claims, rather than pointed out by aforesaid instructions.In meaning or in scope with the scope of claims equivalence in all changes, be all included within its scope.For example, adopt PM optical fiber beam splitter/combiner, implement the embodiment of the spacer array based on full optical fiber, can easily be configured to use together with multiple laser source (such as for example, fiber laser) and fiber amplifier.

Although the preferred embodiments of the present invention are shown specifically, apparent, under the scope of the present invention that the claims below not departing from are illustrated, the modification to these embodiment and reorganization, can be expected by those skilled in the art.For example, the embodiment that the present invention is other, can comprise multiple Faraday rotators 1410,1710(respectively contains corresponding polarization spin fiber parts 1410b, 1710b, is closed in corresponding magnetic element 1410a, 1710a).In addition or in addition, embodiments of the invention can comprise multiple polarization maintaining optical fibre light beam shunts, by sequence or side by side or each other not only by sequence but also be arranged side by side.The embodiment of multiple PM optical

fiber beam shunt

1720,1752 and 1724,1754 sequences that use together with embodiment 1760, shown in Figure 17 B.

Claims

1. have a fiber device for the light path that there is no free space region, this fiber device comprises:

The first multicomponent glass optical fiber, comprising:

Have the 55%-85%(w/w of the first rare-earth oxide) the fibre core of the first doping content; With

Have the 55%-85%(w/w of the second rare-earth oxide) the covering of the second doping content;

Wherein:

This first rare-earth oxide and this second rare-earth oxide select free Pr ₂o ₃, Nd ₂o ₃, Pm ₂o ₃, Sm ₂o ₃, Eu ₂o ₃, Gd ₂o ₃, Tb ₂o ₃, Dy ₂o ₃, Ho ₂o ₃, Er ₂o ₃, Tm ₂o ₃, Yb ₂o ₃, La ₂o ₃, Ga ₂o ₃, Ce ₂o ₃and Lu ₂o ₃the group forming; And

The refractive index of this covering is less than the refractive index of this fibre core; And

Multiple magnetic elements, each formation comprises the hole that perforation magnetic element stretches, and wherein this first optical fiber is placed in the hole of one of the plurality of magnetic element.

2. the fiber device of claim 1, wherein each orientation that is magnetic of the plurality of magnetic element, wherein the plurality of magnetic element is placed by identical magnetic orientation.

3. the fiber device of claim 2, also comprises:

The second multicomponent glass optical fiber, is placed in the hole of another magnetic element in the plurality of magnetic element, and wherein this first and second optical fiber is identical; With

There is the 3rd glass optical fiber of first end and the second end, wherein this first end and this first fused fiber splice, and this second end and this second fused fiber splice.

4. the fiber device of claim 3, wherein the 3rd optical fiber has the character in the group of selecting free following formation:

Second anglec of rotation, wherein this first optical fiber has first anglec of rotation, and wherein under magnetic fluxes density, this first angle is greater than this second anglec of rotation; With

The second sense of rotation, wherein this first optical fiber has first sense of rotation contrary with this second sense of rotation.

5. the fiber device of claim 2, wherein each of the plurality of magnetic element has certain length, and wherein each separated distance of the plurality of magnetic element equals at least this length of half.

6. the fiber device of claim 1, wherein each orientation that is magnetic of the plurality of magnetic element, wherein the plurality of magnetic element is placed by contrary magnetic orientation.

7. the fiber device of claim 6, wherein the plurality of magnetic element each with the plurality of magnetic element at least another contacts physically.

8. the fiber device of claim 6, wherein each of the plurality of magnetic element is by separately.

9. the fiber device of claim 6, also comprises the second optical fiber, is placed in another hole of one of the plurality of magnetic element, and this second optical fiber has the character in the group of selecting free following formation:

Second anglec of rotation, wherein under magnetic fluxes density, this first optical fiber has first anglec of rotation that is greater than this second anglec of rotation; With

10. the fiber device of claim 9, also comprise the 3rd multicomponent glass optical fiber, be placed in the hole of another magnetic element in the plurality of magnetic element, wherein this first optical fiber and the 3rd optical fiber are identical, wherein this second optical fiber has first end and the second end, wherein this first end and this first fused fiber splice, wherein this second end and the 3rd fused fiber splice.

The fiber device of 11. claims 1, has the first port and the second port, and this fiber device also comprises: for defining the first polarizer based on optical fiber of this first port, and for defining the second polarizer based on optical fiber of this second port.

The fiber device of 12. claims 1, wherein first in the plurality of magnetic element comprises the first magnetic material, and wherein second in the plurality of magnetic element comprises the second magnetic material, and wherein this first and second magnetic material is different.

The fiber device of 13. claims 1, wherein each orientation that is magnetic of the plurality of magnetic element, wherein first in the plurality of magnetic element placed by the magnetic orientation identical with in the plurality of magnetic element second, and wherein the 3rd in the plurality of magnetic element places by the magnetic orientation contrary with in the plurality of magnetic element second.

The fiber device of 14. claims 1, wherein this first rare-earth oxide selects free La ₂o ₃, Ga ₂o ₃, Yb ₂o ₃and Ce ₂o ₃the group forming, wherein this fiber device also comprises the fiber laser of wavelength between 1.5 microns to 2.5 microns.

15. 1 kinds have the fiber device of the light path that there is no free space region, and this fiber device comprises:

The first and second multicomponent glass optical fiber, this first and second optical fiber respectively comprises:

Wherein:

Multiple magnetic elements, each formation comprises the hole that perforation magnetic element stretches, and wherein this first optical fiber is placed in the hole of one of the plurality of magnetic element, and this second optical fiber is placed in the hole of another magnetic element of the plurality of magnetic element.

The fiber device of 16. claims 15, wherein the fibre core of this first optical fiber is with the rare-earth oxide doping different from the fibre core of the second optical fiber.

The fiber device of 17. claims 15, wherein each orientation that is magnetic of the plurality of magnetic element, wherein the plurality of magnetic element is placed by identical magnetic orientation, wherein this fiber device also includes the 3rd glass optical fiber of first end and the second end, wherein this first end and this first fused fiber splice, and this second end and this second fused fiber splice, wherein the 3rd optical fiber has the character in the group of selecting free following formation:

The fiber device of 18. claims 15, wherein each orientation that is magnetic of the plurality of magnetic element, wherein the plurality of magnetic element is placed by contrary magnetic orientation, this fiber device also comprises the 3rd optical fiber, be placed in another hole of one of the plurality of magnetic element, wherein the 3rd optical fiber has first end and the second end, wherein this first end and this first fused fiber splice, wherein this second end and this second fused fiber splice, wherein the 3rd optical fiber has the character in the group of selecting free following formation:

The fiber device of 19. claims 15, has the first port and the second port, and this fiber device also comprises: for defining the first polarizer based on optical fiber of this first port, and for defining the second polarizer based on optical fiber of this second port.

20. 1 kinds have the fiber device of the light path that there is no free space region, and this fiber device comprises:

The first multicomponent glass optical fiber, comprising:

Wherein:

The refractive index of this covering is less than the refractive index of this fibre core;

Multiple magnetic elements, each formation comprises the hole that perforation magnetic element stretches, and wherein this first optical fiber is placed in the hole of one of the plurality of magnetic element;

The first polarizer on the first port; With

The second polarizer on the second port;

Wherein be rotated 40 to 50 degree by the polarisation of light of this fiber device transmission.

The fiber device of 21. claims 20, also comprises the second glass optical fiber and the 3rd glass optical fiber, wherein:

Each of the plurality of magnetic element orientation that is magnetic, wherein the plurality of magnetic element is placed by identical magnetic orientation;

This second optical fiber is placed in the hole of another magnetic element of the plurality of magnetic element, and wherein this first and second optical fiber is identical; With

The 3rd optical fiber has first end and the second end, wherein this first end and this first fused fiber splice, and this second end and this second fused fiber splice; And

The 3rd optical fiber has the character in the group of selecting free following formation:

The fiber device of 22. claims 20, also comprises and the second glass optical fiber of the first fused fiber splice, wherein:

Each of the plurality of magnetic element orientation that is magnetic, wherein the plurality of magnetic element is placed by contrary magnetic orientation;

This second optical fiber is placed in another hole of one of the plurality of magnetic element; With

This second optical fiber has the character in the group of selecting free following formation: