WO2021244298A1 - 构成光纤放大器的光器件、光纤放大器以及制造方法 - Google Patents

构成光纤放大器的光器件、光纤放大器以及制造方法 Download PDF

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Publication number
WO2021244298A1
WO2021244298A1 PCT/CN2021/094865 CN2021094865W WO2021244298A1 WO 2021244298 A1 WO2021244298 A1 WO 2021244298A1 CN 2021094865 W CN2021094865 W CN 2021094865W WO 2021244298 A1 WO2021244298 A1 WO 2021244298A1
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Prior art keywords
optical
fiber
optical fiber
gain
lens
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PCT/CN2021/094865
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English (en)
French (fr)
Inventor
操时宜
常志武
李淑杰
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华为技术有限公司
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Publication of WO2021244298A1 publication Critical patent/WO2021244298A1/zh
Priority to US18/073,643 priority Critical patent/US20230098573A1/en

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29346—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by wave or beam interference
    • G02B6/29361—Interference filters, e.g. multilayer coatings, thin film filters, dichroic splitters or mirrors based on multilayers, WDM filters
    • G02B6/2937—In line lens-filtering-lens devices, i.e. elements arranged along a line and mountable in a cylindrical package for compactness, e.g. 3- port device with GRIN lenses sandwiching a single filter operating at normal incidence in a tubular package
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/255—Splicing of light guides, e.g. by fusion or bonding
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/27—Optical coupling means with polarisation selective and adjusting means
    • G02B6/2746—Optical coupling means with polarisation selective and adjusting means comprising non-reciprocal devices, e.g. isolators, FRM, circulators, quasi-isolators
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29379—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device
    • G02B6/2938—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/005—Optical devices external to the laser cavity, specially adapted for lasers, e.g. for homogenisation of the beam or for manipulating laser pulses, e.g. pulse shaping
    • H01S3/0064—Anti-reflection devices, e.g. optical isolaters
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/005—Optical devices external to the laser cavity, specially adapted for lasers, e.g. for homogenisation of the beam or for manipulating laser pulses, e.g. pulse shaping
    • H01S3/0085—Modulating the output, i.e. the laser beam is modulated outside the laser cavity
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/09—Processes or apparatus for excitation, e.g. pumping
    • H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
    • H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
    • H01S3/094049—Guiding of the pump light
    • H01S3/094053—Fibre coupled pump, e.g. delivering pump light using a fibre or a fibre bundle
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/10007—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers
    • H01S3/1001—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers by controlling the optical pumping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/06754—Fibre amplifiers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/06754—Fibre amplifiers
    • H01S3/06758—Tandem amplifiers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/09—Processes or apparatus for excitation, e.g. pumping
    • H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
    • H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
    • H01S3/094003—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light the pumped medium being a fibre

Definitions

  • the present application relates to the field of communications, and more specifically, to an optical device, an optical fiber amplifier, and a manufacturing method that constitute an optical fiber amplifier.
  • the gain fiber in the commonly used fiber amplifier is a silica glass matrix erbium-doped fiber
  • the wavelength division multiplexer (WDM) in the fiber amplifier and the optical device pigtails such as isolators are all quartz Glass matrix fiber, that is, the two matrixes are the same. Since both are silica glass-based fibers, the softening temperature and refractive index of the two are similar, so it is easier to splice the pigtails and gain fibers of WDM and isolator, and the splicing performance indicators are better.
  • gain fibers of other substrates can be used.
  • some soft glass fibers such as tellurium-based erbium-doped fiber (erbium-doped in tellurite glass fiber), fluoride thulium-doped fiber (thulium-doped in fluoride glass fiber) and so on.
  • tellurium-based erbium-doped fiber erbium-doped in tellurite glass fiber
  • fluoride thulium-doped fiber thulium-doped in fluoride glass fiber
  • the fusion splicing of these gain fibers and silica glass matrix fibers that is, the pigtails of optical devices
  • the performance indicators are poor, so the performance of the fiber amplifier is low.
  • the present application provides an optical device, an optical fiber amplifier, and a manufacturing method that constitute an optical fiber amplifier.
  • the pigtail of the optical device can be designed according to requirements, so that the application flexibility of the optical fiber amplifier can be improved, and the use performance of the optical fiber amplifier can be improved. For example, in some designs, the loss at the optical fiber connection can be greatly reduced, thereby increasing the optical amplifier gain, reducing the noise figure, reducing the processing difficulty, reducing the cost, and improving the performance of the optical fiber amplifier composed of heterogeneous fibers.
  • an optical device is provided.
  • the optical device is used in a fiber amplifier.
  • the optical device uses a first optical fiber to connect to a gain fiber, and the gain fiber is used to amplify optical signals;
  • the optical device uses a second fiber or one of the fiber amplifiers.
  • a plurality of second optical devices are connected, and/or the second optical fiber is used to input optical signals or output optical signals amplified by the gain fiber; wherein the softening temperature of the first optical fiber and the second optical fiber is equal to / Or the refractive index is different.
  • the optical device in the fiber amplifier, the fiber connected to the gain fiber, and the other optical device (such as the second optical device) connected to the input optical signal or the output optical signal (such as the optical fiber amplified by the gain fiber).
  • Signal of the optical fiber, the refractive index and/or softening temperature are different.
  • the optical device may be connected to the gain fiber using the first optical fiber, and the optical device may be connected to other optical devices using the second optical fiber, or input optical signals or output optical signals amplified by the gain fiber.
  • the fiber amplifier can be flexibly designed according to requirements, such as designing the pigtails of the optical device (that is, the first fiber and the second fiber), so that the performance of the fiber amplifier can be improved.
  • the first fiber can be designed to be the same or similar to the gain fiber matrix, or the first fiber can be designed to be compatible with the gain fiber softening temperature and/ Or an optical fiber with a small refractive index difference, which can greatly reduce the loss of heterogeneous optical fiber connection.
  • the absolute value of the difference between the softening temperature of the first optical fiber and the second optical fiber is greater than the softening temperature of the first optical fiber and the gain fiber
  • the absolute value of the refractive index difference between the first fiber and the second fiber is greater than the absolute value of the refractive index difference between the first fiber and the gain fiber value
  • the matrix of the first fiber is the same as or similar to the matrix of the gain fiber.
  • the absolute value of the difference is used to reflect the difference. If the absolute value of the difference between the softening temperature of the first fiber and the second fiber is greater than the absolute value of the difference between the softening temperature of the first fiber and the gain fiber, it means that the difference between the softening temperature of the first fiber and the second fiber is greater than The difference in softening temperature between the first fiber and the gain fiber.
  • the absolute value of the refractive index difference between the first fiber and the second fiber is greater than the absolute value of the refractive index difference between the first fiber and the gain fiber, that is, the difference between the refractive index of the first fiber and the second fiber The difference is greater than the difference in refractive index between the first fiber and the gain fiber.
  • the absolute value of the difference between the softening temperature of the first fiber and the second fiber is greater than the absolute value of the difference between the softening temperature of the first fiber and the gain fiber; and/or the difference between the first fiber and the second fiber
  • the absolute value of the difference in refractive index is greater than the absolute value of the difference in refractive index between the first fiber and the gain fiber.
  • the optical device in the fiber amplifier can use the first fiber that is the same as or close to the gain fiber matrix to connect to the gain fiber, and the optical device uses the second fiber that is different from the gain fiber matrix to connect to other optical devices or input optical signals or output optical signals. Connected.
  • the matrix of the fiber connected to the gain fiber is the same or similar to the matrix of the gain fiber. Therefore, the loss at the optical fiber connection can be greatly reduced. In addition, the reduction of optical fiber connection loss will help increase the gain of the optical amplifier, reduce the noise figure, reduce the processing difficulty, and reduce the cost. It is expected to become a necessary technology for the L/S band optical amplifier.
  • the optical signal input by the optical device through the second optical fiber reaches the first optical fiber through at least a section of free space; or, the optical device passes through The optical signal input by the first optical fiber reaches the second optical fiber through at least a section of free space.
  • the optical device includes at least one capillary, and the at least one capillary is used to remove the coating from the first optical fiber and/or the first optical fiber. Two optical fibers are introduced into the optical device.
  • the optical device includes at least one optical fiber head, and the at least one optical fiber head is used to introduce the first optical fiber and/or the second optical fiber from which the coating layer is stripped into the optical device.
  • the capillary tube mentioned below can be replaced with an optical fiber tip.
  • the optical fiber head is a whole, and the capillary tube is a key part of the optical fiber head.
  • the optical fiber is introduced into the optical device, or in other words, the optical fiber is assembled to the optical device. It does not limit the transmission direction of the optical signal in the optical fiber.
  • the introduced optical fiber can be used to input optical signals, can also be used to output optical signals, and can also be used to input and output optical signals at the same time.
  • the first optical fiber and the gain optical fiber are connected by fusion splicing.
  • the optical device is any one or more of the following: a wavelength division multiplexer WDM, an isolator, and an optical fiber adapter.
  • the WDM is used to send pump light emitted by a pump laser into the gain fiber.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber adapter is used to connect the first optical fiber and the second optical fiber.
  • the optical device is a WDM
  • the WDM includes a dual-line capillary, and the dual-line capillary is used to introduce two optical fibers into the WDM;
  • One of the optical fibers is the first optical fiber;
  • the other of the two optical fibers is the second optical fiber, and the other of the two optical fibers is used to connect a pump laser , Or used to input optical signals, or used to output optical signals amplified by the gain fiber.
  • the WDM is used to send the pump light emitted by the pump laser into the gain fiber.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the WDM includes a first lens, and the first lens is used to adjust the light beams of the optical signals in the two optical fibers in the double-line capillary.
  • the radius of curvature of the curved portion of the optical path of the optical signal in the first optical fiber corresponding to the first lens is smaller than that of the first lens corresponding to the first optical fiber.
  • the radius of curvature of the curved part of the optical path of the optical signal in the second optical fiber; or, the radial refractive index of the optical path of the optical signal in the first lens corresponding to the change in the radial refractive index of the optical signal in the first optical fiber is faster than that of the first lens corresponding to the optical path.
  • the radial refractive index of the optical path of the optical signal in the second optical fiber changes.
  • the first lens supports different mode spots of the optical signals in the two optical fibers in the dual-line capillary.
  • the mode spots of the optical signals in the two optical fibers in the dual-line capillary match.
  • the optical device is an isolator
  • the isolator includes a first single-line capillary tube and a second single-line capillary tube
  • the first single-line capillary tube is used to introduce the The first optical fiber enters the isolator
  • the second single-line capillary is used to introduce the second optical fiber into the isolator.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber in the first single-line capillary and the optical fiber in the second single-line capillary are not parallel.
  • the isolator includes a second lens and a third lens, and the second lens is used to adjust the optical signal of the optical fiber in the first single-line capillary.
  • the light beam, the third lens is used to adjust the light beam of the optical signal of the optical fiber in the second single-line capillary.
  • the focal length of the second lens is smaller than the focal length of the third lens.
  • the optical device is an optical fiber adapter
  • the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube
  • the third single-line capillary tube is used to introduce The first optical fiber enters the optical fiber adapter
  • the fourth single-line capillary is used to introduce the second optical fiber into the optical fiber adapter.
  • the optical fiber in the third single-line capillary and the optical fiber in the fourth single-line capillary are not parallel.
  • the optical fiber adapter includes a fourth lens and a fifth lens
  • the fourth lens is used to adjust the optical signal of the optical fiber in the third single-line capillary.
  • the fifth lens is used to adjust the optical signal beam of the optical fiber in the fourth single-line capillary.
  • the focal length of the fourth lens is smaller than the focal length of the fifth lens.
  • an optical device is provided.
  • the optical device is used in an optical fiber amplifier.
  • the optical device is directly connected to the gain fiber, and the gain fiber is used to amplify optical signals;
  • the optical device uses a second optical fiber and one or more of the optical fiber amplifiers.
  • the second optical device is connected, and/or, the second optical fiber is used to input optical signals or output optical signals amplified by the gain fiber; wherein the softening temperature and/or refraction of the second optical fiber and the gain fiber The rates are different.
  • the first optical device is directly connected to the gain fiber, that is, the pigtail connected to the first optical device and the gain fiber is directly the gain fiber, and there is no fusion point between the first optical device and the gain fiber.
  • the optical fiber has a different refractive index and/or softening temperature.
  • the optical device may be directly connected to the gain fiber, and the optical device may be connected to other optical devices, the input optical signal, or the optical signal amplified by the output gain fiber by using the second optical fiber. In this way, the loss of heterogeneous fiber connection can be minimized, which helps to increase the gain of the optical amplifier, reduce the noise figure, reduce the processing difficulty, and reduce the cost. It is expected to become a necessary technology for the L/S band optical amplifier.
  • the optical signal input by the optical device through the second optical fiber reaches the gain fiber through at least a section of free space; or, the optical device passes through all The optical signal input by the gain fiber reaches the second fiber through at least a section of free space.
  • the optical device includes at least one capillary, and the at least one capillary is used to remove the coating from the second optical fiber and/or the gain The optical fiber is introduced into the optical device.
  • the optical device is any one or more of the following: a wavelength division multiplexer WDM, an isolator, and an optical fiber adapter.
  • the WDM is used to send pump light emitted by a pump laser into the gain fiber.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber adapter is used to connect the second optical fiber and the gain optical fiber.
  • the optical device is a WDM
  • the WDM includes a dual-line capillary, and the dual-line capillary is used to introduce two optical fibers into the WDM;
  • One of the two fibers is the gain fiber;
  • the other of the two fibers is the second fiber, and the other of the two fibers is used to connect a pump laser, Or used to input optical signals, or used to output optical signals amplified by the gain fiber.
  • the WDM is used to send the pump light emitted by the pump laser into the gain fiber.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the WDM includes a first lens, and the first lens is used to adjust the light beams of the optical signals in the two optical fibers in the double-line capillary.
  • the radius of curvature of the curved portion of the optical path of the optical signal in the gain fiber corresponding to the first lens is smaller than that of the first lens corresponding to the second lens.
  • the radius of curvature of the curved portion of the optical path of the optical signal in the optical fiber; or, the radial refractive index of the optical path of the optical signal in the gain fiber corresponding to the first lens changes faster than that of the first lens corresponding to the first lens.
  • the radial refractive index of the optical path of the optical signal in the two optical fibers changes.
  • the first lens supports different mode spots of the optical signals in the two optical fibers in the dual-line capillary.
  • the mode spots of the optical signals in the two optical fibers in the dual-line capillary match.
  • the optical device is an isolator
  • the isolator includes a first single-line capillary tube and a second single-line capillary tube
  • the first single-line capillary tube is used to introduce the The gain fiber enters the isolator
  • the second single-line capillary is used to introduce the second optical fiber into the isolator.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber in the first single-line capillary and the optical fiber in the second single-line capillary are not parallel.
  • the isolator includes a second lens and a third lens, and the second lens is used to adjust the optical signal of the optical fiber in the first single-line capillary.
  • the light beam, the third lens is used to adjust the light beam of the optical signal of the optical fiber in the second single-line capillary.
  • the focal length of the second lens is smaller than the focal length of the third lens.
  • the optical device is an optical fiber adapter
  • the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube
  • the third single-line capillary tube is used to introduce The gain fiber enters the optical fiber adapter
  • the fourth single-line capillary is used to introduce the second optical fiber into the optical fiber adapter.
  • the optical fiber in the third single-line capillary and the optical fiber in the fourth single-line capillary are not parallel.
  • the optical fiber adapter includes a fourth lens and a fifth lens
  • the fourth lens is used to adjust the optical signal of the optical fiber in the third single-line capillary.
  • the fifth lens is used to adjust the optical signal beam of the optical fiber in the fourth single-line capillary.
  • the focal length of the fourth lens is smaller than the focal length of the fifth lens.
  • an optical fiber amplifier in the third aspect, includes a first optical device, a gain fiber, and one or more second optical devices.
  • the gain fiber is used to amplify an optical signal; the first optical device is connected to the gain fiber by using a first optical fiber;
  • the first optical device uses a second optical fiber to connect to the one or more second optical devices, and/or uses the second optical fiber to input optical signals or output optical signals amplified by the gain fiber; wherein, The softening temperature and/or refractive index of the first optical fiber and the second optical fiber are different.
  • the first optical device is the optical device described in the first aspect and any possible implementation manner of the first aspect.
  • an optical fiber amplifier in the fourth aspect, includes a first optical device, a gain fiber, and one or more second optical devices.
  • the gain fiber is used to amplify optical signals; the first optical device is directly connected to the gain fiber;
  • the device uses a second optical fiber to connect to the one or more second optical devices, and/or uses the second optical fiber to input optical signals or output optical signals amplified by the gain fiber; wherein, the second optical fiber
  • the softening temperature and/or refractive index of the optical fiber and the gain optical fiber are different.
  • the first optical device is the optical device described in the second aspect and any possible implementation manner of the second aspect.
  • a method for manufacturing an optical device includes: using a first optical fiber to connect to a gain fiber, where the gain fiber is used to amplify an optical signal; using a second optical fiber to connect to one or more second optical devices, and/or, using the second optical fiber to input light Signal or output the optical signal amplified by the gain fiber; wherein the softening temperature and/or refractive index of the first fiber and the second fiber are different.
  • the absolute value of the difference between the softening temperature of the first optical fiber and the second optical fiber is greater than the softening temperature of the first optical fiber and the gain fiber The absolute value of the difference.
  • the absolute value of the refractive index difference between the first optical fiber and the second optical fiber is greater than the refractive index of the first optical fiber and the gain fiber The absolute value of the difference.
  • the matrix of the first fiber is the same as or similar to the matrix of the gain fiber.
  • the optical signal input through the second optical fiber reaches the first optical fiber through at least a section of free space; or, the light input through the first optical fiber The signal reaches the second optical fiber through at least a section of free space.
  • the optical device includes at least one capillary, through which the first optical fiber and/or the second optical fiber from which the coating layer is stripped is removed. The optical fiber is introduced into the optical device.
  • the first optical fiber and the gain optical fiber are connected by fusion splicing.
  • the optical component is any one or more of the following: a wavelength division multiplexer WDM, an isolator, and an optical fiber adapter.
  • the WDM is used to send pump light emitted by a pump laser into the gain fiber.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber adapter is used to connect the first optical fiber and the second optical fiber.
  • the optical device is a WDM
  • the WDM includes a double-wire capillary, and two optical fibers are introduced into the WDM through the double-wire capillary;
  • One of the optical fibers is the first optical fiber;
  • the other of the two optical fibers is the second optical fiber, and the other of the two optical fibers is used to connect a pump laser, Or used to input optical signals, or used to output optical signals amplified by the gain fiber.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the WDM includes a first lens through which the light beams of the optical signals in the two optical fibers in the double-line capillary are adjusted.
  • the radius of curvature of the curved portion of the optical path of the optical signal in the first optical fiber corresponding to the first lens is smaller than that of the first lens corresponding to the first lens.
  • the radius of curvature of the curved part of the optical path of the optical signal in the second optical fiber; or, the radial refractive index of the optical path of the optical signal in the first lens corresponding to the change in the radial refractive index of the optical signal in the first optical fiber is faster than that of the first lens corresponding to the optical path.
  • the radial refractive index of the optical path of the optical signal in the second optical fiber changes.
  • the first lens supports different mode spots of the optical signals in the two optical fibers in the double-line capillary.
  • the mode spots of the optical signals in the two optical fibers in the dual-line capillary match.
  • the optical device is an isolator
  • the isolator includes a first single-line capillary tube and a second single-line capillary tube.
  • An optical fiber enters the isolator, and the second optical fiber enters the isolator through the second single-line capillary tube.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber in the first single-line capillary and the optical fiber in the second single-line capillary are not parallel.
  • the isolator includes a second lens and a third lens, and the optical signal beam of the optical fiber in the first single-line capillary is adjusted by the second lens , Adjusting the light beam of the optical signal of the optical fiber in the second single-line capillary through the third lens.
  • the focal length of the second lens is smaller than the focal length of the third lens.
  • the optical device is an optical fiber adapter
  • the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube.
  • the first optical fiber enters the optical fiber adapter
  • the second optical fiber enters the optical fiber adapter through the fourth single-line capillary tube.
  • the optical fiber in the third single-line capillary and the optical fiber in the fourth single-line capillary are not parallel.
  • the optical fiber adapter includes a fourth lens and a fifth lens, and the optical signal of the optical fiber in the third single-line capillary is adjusted by the fourth lens.
  • the light beam adjusts the light beam of the optical signal of the optical fiber in the fourth single-line capillary through the fifth lens.
  • the focal length of the fourth lens is smaller than the focal length of the fifth lens.
  • a method for manufacturing an optical device includes: directly connecting the gain fiber, which is used to amplify optical signals; using a second fiber to connect to one or more second optical devices in the fiber amplifier, and/or, using the second fiber
  • the optical signal is input or the optical signal amplified by the gain fiber is output; wherein the softening temperature and/or refractive index of the second fiber and the gain fiber are different.
  • the optical signal input through the second optical fiber reaches the gain fiber through at least a section of free space; or, the optical signal input through the gain fiber, The second optical fiber is reached at least through a section of free space.
  • the optical device includes at least one capillary tube, and the second optical fiber and/or the gain optical fiber with the coating layer stripped off through the at least one capillary tube Introduce into the optical device.
  • the optical device is any one or more of the following: a wavelength division multiplexer WDM, an isolator, and an optical fiber adapter.
  • the WDM is used to send pump light emitted by a pump laser into the gain fiber.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber adapter is used to connect the second optical fiber and the gain optical fiber.
  • the optical device is a WDM
  • the WDM includes a dual-line capillary, and two optical fibers are introduced into the WDM through the dual-line capillary;
  • One of the fibers is the gain fiber;
  • the other of the two fibers is the second fiber, and the other of the two fibers is used to connect a pump laser, or It is used to input optical signals or output optical signals amplified by the gain fiber.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the WDM includes a first lens, and the light beams of the optical signals in the two optical fibers in the double-line capillary are adjusted by the first lens.
  • the curvature radius of the curved portion of the optical path of the optical signal in the gain fiber corresponding to the first lens is smaller than that of the first lens corresponding to the second lens.
  • the radius of curvature of the curved portion of the optical path of the optical signal in the optical fiber; or, the radial refractive index of the optical path of the optical signal in the gain fiber corresponding to the first lens changes faster than that of the first lens corresponding to the first lens.
  • the radial refractive index of the optical path of the optical signal in the two optical fibers changes.
  • the first lens supports different modes of optical signals in the two optical fibers in the double-line capillary.
  • the mode spots of the optical signals in the two optical fibers in the dual-line capillary match.
  • the optical device is an isolator
  • the isolator includes a first single-line capillary tube and a second single-line capillary tube
  • the gain is introduced through the first single-line capillary tube
  • the optical fiber enters the isolator, and the second optical fiber is introduced into the isolator through the second single-line capillary tube.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the optical fiber in the first single-line capillary and the optical fiber in the second single-line capillary are not parallel.
  • the isolator includes a second lens and a third lens, and the optical signal beam of the optical fiber in the first single-line capillary is adjusted by the second lens , Adjusting the light beam of the optical signal of the optical fiber in the second single-line capillary through the third lens.
  • the focal length of the second lens is smaller than the focal length of the third lens.
  • the optical device is an optical fiber adapter
  • the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube.
  • the gain fiber enters the optical fiber adapter, and the second optical fiber is introduced into the optical fiber adapter through the fourth single-line capillary tube.
  • the optical fiber in the third single-line capillary and the optical fiber in the fourth single-line capillary are not parallel.
  • the optical fiber adapter includes a fourth lens and a fifth lens, and the optical signal of the optical fiber in the third single-line capillary is adjusted by the fourth lens.
  • the light beam adjusts the light beam of the optical signal of the optical fiber in the fourth single-line capillary through the fifth lens.
  • the focal length of the fourth lens is smaller than the focal length of the fifth lens.
  • a method for manufacturing an optical fiber amplifier includes a first optical device, a gain fiber, and one or more second optical devices.
  • the gain fiber is used to amplify an optical signal.
  • the method includes: using a first optical fiber to connect the first optical device to the Gain fiber; using a second fiber to connect the first optical device and the one or more second optical devices, and/or, using the second fiber to input optical signals or output optical signals amplified by the gain fiber Wherein, the softening temperature and/or refractive index of the first optical fiber and the second optical fiber are different.
  • the first optical device is the optical device described in the first aspect and any possible implementation manner of the first aspect, or the first optical device
  • the optical device is an optical device manufactured based on the fifth aspect and the method described in any possible implementation manner of the fifth aspect.
  • a method for manufacturing an optical fiber amplifier includes a first optical device, a gain fiber, and one or more second optical devices.
  • the gain fiber is used to amplify an optical signal.
  • the method includes: directly connecting the first optical device and the gain fiber; A second optical fiber is used to connect the first optical device and the one or more second optical devices, and/or the second optical fiber is used to input optical signals or output optical signals amplified by the gain fiber; wherein, The softening temperature and/or refractive index of the second fiber and the gain fiber are different.
  • the first optical device is the optical device described in the second aspect and any possible implementation manner of the second aspect, or the first optical device
  • the optical device is an optical device manufactured based on the sixth aspect and the method described in any possible implementation manner of the sixth aspect.
  • a method for manufacturing a wavelength division multiplexer WDM is provided.
  • the WDM is applied to an optical fiber amplifier, the WDM includes a two-wire capillary, and the method includes: introducing two optical fibers into the WDM through the two-wire capillary, one of the two optical fibers is the first optical fiber Or gain fiber, the other fiber of the two fibers is the second fiber, and the other fiber of the two fibers is used for connecting a pump laser, or for inputting optical signals, or for outputting The optical signal amplified by the gain fiber, wherein the softening temperature and/or refractive index of the first fiber and the second fiber are different, or the softening temperature and/or the softening temperature of the second fiber and the gain fiber are different Or the refractive index is different.
  • the WDM is the WDM described in any one of the first aspect to the eighth aspect.
  • a method for manufacturing an isolator is provided.
  • the isolator is applied to an optical fiber amplifier, and the isolator includes a first single-line capillary tube and a second single-line capillary tube.
  • the method includes: introducing a first optical fiber or gain fiber into the isolator through the first single-line capillary tube;
  • the second single-line capillary leads the second optical fiber into the isolator; wherein the softening temperature and/or refractive index of the first optical fiber and the second optical fiber are different, or the second optical fiber and the gain The softening temperature and/or refractive index of the optical fiber are different.
  • the isolator is the isolator according to any one of the first aspect to the eighth aspect.
  • a method for manufacturing an optical fiber adapter is provided.
  • the optical fiber adapter is applied to an optical fiber amplifier, and the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube.
  • Connector introduce a second optical fiber into the optical fiber adapter through the fourth single-line capillary; wherein the softening temperature and/or refractive index of the first optical fiber and the second optical fiber are different, or, the second optical fiber It is different from the softening temperature and/or refractive index of the gain fiber.
  • the optical fiber adapter is the optical fiber adapter according to any one of the first aspect to the eighth aspect.
  • a lens is provided.
  • the optical path through the lens includes a first optical path and a second optical path; the radius of curvature of the curved portion of the lens corresponding to the first optical path is smaller than the curvature radius of the curved portion of the lens corresponding to the second optical path; or, so The change of the radial refractive index of the lens corresponding to the first optical path is faster than the change of the radial refractive index of the lens corresponding to the second optical path.
  • the lens is the first lens described in the first aspect or the second aspect and any possible implementation manner of the first aspect or the second aspect .
  • Fig. 1 is a schematic diagram of an application scenario suitable for an embodiment of the present application.
  • Fig. 2 shows a schematic structural diagram of an optical fiber amplifier suitable for an embodiment of the present application.
  • Fig. 3 shows a schematic diagram of the refractive index of a heterogeneous fiber with different refractive index.
  • Fig. 4 is a schematic diagram of an optical fiber amplifier provided according to an embodiment of the present application.
  • Fig. 5 shows a schematic diagram of an optical fiber amplifier suitable for an embodiment of the present application.
  • Fig. 6 shows a schematic diagram of an optical fiber amplifier suitable for another embodiment of the present application.
  • Fig. 7 shows a schematic diagram of an optical fiber amplifier suitable for another embodiment of the present application.
  • Fig. 8 shows a schematic diagram of a fiber amplifier suitable for still another embodiment of the present application.
  • Fig. 9 shows a schematic diagram of WDM applicable to embodiments of the present application.
  • FIG. 10 shows a schematic diagram of a diaphragm of a space-type WDM suitable for an embodiment of the present application.
  • FIG. 11 shows a schematic diagram of adjusting the angle between two optical fibers in a dual-line capillary suitable for an embodiment of the present application.
  • Figures 12 to 13 show schematic diagrams of lenses suitable for embodiments of the present application.
  • Fig. 14 shows a schematic diagram of an isolator suitable for embodiments of the present application.
  • Fig. 15 shows a schematic diagram of an optical fiber adapter suitable for an embodiment of the present application.
  • FIG. 16 is a schematic diagram of a method for manufacturing an optical device according to an embodiment of the present application.
  • FIG. 17 is a schematic diagram of a method for manufacturing an optical device according to another embodiment of the present application.
  • Fig. 18 is a schematic diagram of a method for manufacturing an optical fiber amplifier according to an embodiment of the present application.
  • Fig. 19 is a schematic diagram of a method for manufacturing an optical fiber amplifier according to another embodiment of the present application.
  • the technical solutions of the embodiments of this application can be applied to optical fiber communication networks.
  • the technical solutions of the embodiments of this application can be used in optical fiber amplifiers in optical fiber communication networks.
  • Network element The technical solutions of the embodiments of the present application can be used to realize a fiber amplifier composed of heterogeneous fibers, and can also be used to realize a fiber composed of fibers with different mode spots (including different mode spot diameters, and/or different numerical apertures).
  • Amplifier The following describes in detail the scenario applicable to the embodiment of the present application with reference to FIG. 1.
  • Fig. 1 is a schematic diagram of an application scenario suitable for an embodiment of the present application.
  • an optical fiber communication network it may include an optical transmitter, an optical receiver, and may also include one or more optical fiber amplifiers.
  • the optical fiber amplifier is mainly located in the middle of the optical fiber line (or line fiber) in the optical fiber communication network to realize the amplification of the optical signal and extend the transmission distance of the optical signal.
  • FIG. 1 is only an exemplary illustration, and the application is not limited thereto.
  • more optical devices may be included in the optical fiber communication network; for another example, the embodiments of the present application may also be applied to any scene including optical fiber amplifiers.
  • the fiber amplifier may include, but is not limited to, a pump laser, a wavelength division multiplexer (WDM), an isolator, and a gain fiber, for example.
  • the pump laser generates pump light
  • WDM can combine the input optical signal (or input signal light) and the pump light together and send it to the gain fiber.
  • the gain fiber may be a fiber in which a gain medium is doped.
  • the pump light excites the gain medium ions in the gain fiber to a high energy level. After the input of the input optical signal, it will cause the gain medium ions in the gain fiber to transition from a high energy level to a low energy level, and stimulated radiation will occur, thereby amplifying the input
  • the output optical signal is obtained.
  • fiber fusion splicing is generally used between gain fiber and WDM, and between gain fiber and isolator, which can reduce loss and reduce noise figure.
  • the pigtail of the WDM is fusion spliced with the gain fiber
  • the pigtail of the isolator is spliced with the gain fiber.
  • the gain fiber in the commonly used fiber amplifier is a silica glass matrix erbium-doped fiber
  • the pigtails of optical devices such as WDM and isolators are all silica glass matrix fibers, that is, the two matrixes are the same. Since both are silica glass matrix fibers, the softening temperature and refractive index of the two are basically the same. Therefore, it is easier to splice the pigtails and gain fibers of WDM and isolator, and the splicing performance indicators are also better.
  • the insertion loss ie insertion loss
  • the return loss ie return loss
  • gain fibers of other substrates can be used.
  • some soft glass fibers such as tellurium-based erbium-doped fiber (erbium-doped in tellurite glass fiber), fluoride thulium-doped fiber (thulium-doped in fluoride glass fiber) and so on.
  • tellurium-based erbium-doped fiber erbium-doped in tellurite glass fiber
  • fluoride thulium-doped fiber thulium-doped in fluoride glass fiber
  • the soft glass fiber Take the soft glass fiber as the gain fiber, and the silica glass matrix fiber as the pigtail of the optical device such as WDM and isolator.
  • the softening temperature of the soft glass fiber is different from that of the silica glass matrix fiber. Therefore, the soft glass fiber has been softened during splicing but the silica glass matrix fiber will not.
  • the soft glass fiber is deformed at the fusion splice and the splicing loss becomes larger, generally 1 to 3 dB.
  • the refractive index of soft glass fiber is generally different from that of silica glass matrix fiber.
  • the refractive index of the silica glass matrix fiber is about 1.47, and the soft glass fiber may reach 2.0.
  • Two kinds of optical fibers have a strong reflection when they are directly fusion spliced in a flat cut, and generally need to be spliced at an oblique angle.
  • fusion splicing at an oblique angle because the refractive index of the soft glass fiber and the silica glass matrix fiber are different, refraction will occur on the fusion bevel.
  • the pattern spot mismatch of the two fibers is more serious, and the insertion loss becomes larger, as shown in Figure 3.
  • the silica glass matrix fiber has not been softened but the soft glass fiber has been softened, it is more likely to cause the longitudinal displacement of the two fiber cores, which further increases the splicing loss.
  • the present application provides a low-cost, high-performance optical fiber amplifier composed of heterogeneous fibers.
  • the gain fiber and the silica glass matrix fiber can be connected to form a fiber amplifier.
  • Fig. 4 is a schematic diagram of a fiber amplifier according to an embodiment of the present application.
  • the optical fiber amplifier may include, a first optical device, one or more second optical devices, and a gain fiber. It can be understood that the gain fiber can be used to amplify optical signals.
  • the first optical component is connected to the gain fiber, and the first fiber is used to connect to the gain fiber or directly to the gain fiber;
  • the first optical device uses a second optical fiber to connect to one or more second optical devices, and/or uses the second optical fiber to input/output optical signals (that is, use the second optical fiber to input optical signals or output optical signals amplified by the gain fiber Signal);
  • the softening temperature and/or refractive index of the first optical fiber and the second optical fiber are different, or the softening temperature and/or refractive index of the second optical fiber and the gain fiber are different.
  • connection of the first optical component to the gain fiber includes at least the following two solutions:
  • Solution 1 The first optical device uses the first optical fiber to connect to the gain optical fiber, as shown in (1) in FIG. 4.
  • the softening temperature and/or refractive index of the first optical fiber and the second optical fiber are different.
  • the first optical device is directly connected to the gain fiber, as shown in (2) in Figure 4.
  • the softening temperature and/or refractive index of the second fiber and the gain fiber are different.
  • the first optical device is directly connected to the gain fiber, that is, the pigtail of the first optical device connected to the gain fiber is the gain fiber, and there is no fusion point between the first optical device and the gain fiber.
  • the optical fiber amplifier composed of heterogeneous fibers provided in the embodiments of the present application is succinctly hereinafter referred to as heterogeneous optical fiber amplifier.
  • the optical device constituting the heterogeneous optical fiber amplifier is connected to other optical devices and the optical fiber connecting to the gain fiber is different, so Higher flexibility and higher performance.
  • the first optical device in the heterogeneous fiber amplifier uses the first optical fiber to connect to the gain fiber; the first optical device in the heterogeneous optical fiber amplifier uses the second optical fiber to connect with other optical devices or input light Signal or output optical signal.
  • the first optical device in the heterogeneous fiber amplifier is directly connected to the gain fiber, that is, the pigtail connected to the first optical device and the gain fiber is the gain fiber, and the first optical device is connected to the gain fiber.
  • the first optical device in the heterogeneous fiber amplifier uses the second optical fiber to connect with other optical devices or input optical signals or output optical signals. In this way, the optical fiber amplifier can be flexibly designed and used according to requirements, and the performance of the optical fiber amplifier can be improved.
  • the first fiber when the fusion splicing performance between the first fiber and the gain fiber needs to be improved, the first fiber can be designed to be the same or similar to the matrix of the gain fiber, or the first fiber can be designed to be the same as or similar to the matrix of the gain fiber.
  • the first optical fiber adopts a passive optical fiber with the same or similar matrix as the gain fiber.
  • the passive optical fiber means an optical fiber without gain medium doped therein, or the first optical fiber directly adopts the gain optical fiber.
  • the first optical fiber and the gain optical fiber are connected in a fusion splicing manner, that is, there is a fusion splice point between the first optical fiber and the gain optical fiber.
  • a fusion splicing manner that is, there is a fusion splice point between the first optical fiber and the gain optical fiber.
  • the first fiber uses the same or similar fiber as the gain fiber matrix, or the first fiber is a fiber with a smaller softening temperature and/or refractive index difference with the gain fiber, the loss of the fusion splice between the first fiber and the gain fiber, The performance index of return loss is better.
  • the first optical device can be designed to be directly connected to the gain fiber, that is, the pigtail connected to the gain fiber of the first optical device is directly the gain fiber, and there is no fusion point between the first optical device and the gain fiber.
  • the gain fiber is directly connected or assembled into the first optical device. Since there is no need for fusion splicing between the first optical component and the gain fiber, there is no fusion splice point, so compared to the above scheme 1, the loss of the heterogeneous fiber connection can be further reduced, and the performance of the heterogeneous fiber amplifier (such as the performance of gain and noise figure) can be improved. Wait).
  • the first optical component and the gain fiber are connected as a whole, which is not convenient to adjust the length of the gain fiber. Therefore, the scheme 2 is more suitable for implementation when the consistency of the gain fiber is relatively good, that is to say, the above Scheme 2 has relatively high requirements for the consistency of the gain fiber.
  • first optical fiber and the second optical fiber are only named for distinction, and their naming does not limit the protection scope of the embodiments of the present application.
  • the difference in softening temperature between the first fiber and the second fiber is greater than the difference in softening temperature between the first fiber and the gain fiber; and/or the difference in refractive index between the first fiber and the second fiber is greater than that of the first fiber and The difference in the refractive index of the gain fiber.
  • This difference includes the absolute value of the difference, the relative value of the absolute value of the difference, and so on.
  • the absolute value of the difference between the softening temperature of the first fiber and the second fiber is greater than the absolute value of the difference between the softening temperature of the second fiber and the gain fiber; and/or the refractive index of the first fiber and the second fiber
  • the absolute value of the difference is greater than the absolute value of the difference between the refractive indexes of the first fiber and the gain fiber.
  • the matrix of the first fiber is the same as or close to the matrix of the gain fiber.
  • the softening temperature of the fiber connecting the first optical device and the gain fiber is the same as or close to the softening temperature of the gain fiber, and the absolute value of the difference between the softening temperature of the first fiber and the second fiber is greater than that of the first fiber and the gain fiber.
  • the absolute value of the difference between the softening temperature, that is, the softening temperature of the second fiber is significantly different from the first fiber and the gain fiber.
  • the refractive index of the first fiber is the same as or close to the refractive index of the gain fiber.
  • the absolute value of the refractive index difference between the first fiber and the second fiber is greater than the absolute value of the refractive index difference between the first fiber and the gain fiber.
  • the matrices of any two of the first fiber, the second fiber, and the gain fiber may be the same or different.
  • any first optical fiber that meets the following conditions is applicable to the embodiments of the present application: the difference in softening temperature or refractive index between the second optical fiber and the first optical fiber is greater than that of the first optical fiber and the first optical fiber.
  • the difference in softening temperature or refractive index between gain fibers is greater than that of the first optical fiber and the first optical fiber.
  • the embodiment of the present application does not limit it.
  • Two types of fibers with different substrates such as two types of fibers with different softening temperatures, or two types of fibers with different refractive indexes, are applicable to Examples of this application.
  • the second optical fiber may be a silica glass matrix fiber
  • the first fiber or the gain fiber is an optical fiber of another matrix different from the silica glass matrix fiber.
  • the first fiber or gain fiber can be a soft glass fiber, such as a tellurium-based erbium-doped fiber (erbium-doped in a tellurite glass fiber), a fluoride thulium-doped fiber (a fluoride glass fiber with thulium-doped ) Etc.
  • the first fiber or the gain fiber may also be a fiber of another matrix different from the second fiber, which is not limited.
  • the first optical fiber in the following embodiments may be replaced with a soft glass optical fiber
  • the second optical fiber may be replaced with a silica glass matrix optical fiber
  • the first optical device represents the optical device in the fiber amplifier.
  • the first optical component may be one or more of WDM, isolator, and fiber optic adapter.
  • the first optical device is WDM.
  • the optical fiber connecting WDM to the gain fiber is the first optical fiber
  • the optical fiber connecting WDM to the pump laser and the optical fiber inputting the optical signal is the second optical fiber.
  • the difference in softening temperature between the first fiber and the second fiber is greater than the difference in softening temperature between the first fiber and the gain fiber; and/or the difference in refractive index between the first fiber and the second fiber is greater than the refraction of the first fiber and the gain fiber The difference in rates.
  • the matrix of the first fiber and the matrix of the gain fiber are the same or close, that is, the matrix of the fiber connecting the WDM and the gain fiber and the matrix of the gain fiber are the same or close.
  • the glass structure of the first optical fiber and the gain fiber are the same or close, that is, the glass structure of the optical fiber connecting the WDM and the gain fiber is the same or close to the gain fiber.
  • the first optical fiber and the gain optical fiber are connected in a fusion splicing manner, that is, there is a fusion splicing point between the first optical fiber and the gain optical fiber.
  • WDM is directly connected to the gain fiber.
  • the gain fiber is directly introduced or assembled into the WDM, and there is no fusion point between the WDM and the gain fiber.
  • the optical fiber connecting the WDM to the pump laser and the optical fiber inputting the optical signal is the second optical fiber.
  • the first optical device is an isolator.
  • the optical fiber connecting the isolator and the gain fiber is the first optical fiber
  • the optical fiber connecting the isolator and the optical fiber outputting the optical signal is the second optical fiber.
  • the absolute value of the difference between the softening temperature of the first fiber and the second fiber is greater than the absolute value of the difference between the softening temperature of the first fiber and the gain fiber; and/or the difference between the refractive index of the first fiber and the second fiber
  • the absolute value of is greater than the absolute value of the difference between the refractive index of the first fiber and the gain fiber.
  • the matrix of the first optical fiber and the matrix of the gain fiber are the same or close, that is, the matrix of the fiber connecting the isolator and the gain fiber and the matrix of the gain fiber are the same or close.
  • the glass structure of the first optical fiber and the gain fiber are the same or close, that is, the glass structure of the optical fiber connecting the WDM and the gain fiber is the same or close to the gain fiber.
  • the first optical fiber and the gain optical fiber are connected in a fusion splicing manner, that is, there is a fusion splicing point between the first optical fiber and the gain optical fiber.
  • the isolator is directly connected to the gain fiber.
  • the gain fiber is directly introduced into the isolator or the gain fiber is directly assembled into the isolator, and there is no fusion point between the isolator and the gain fiber.
  • the optical fiber connecting the isolator and the optical fiber outputting the optical signal is the second optical fiber.
  • the first optical component is an optical fiber adapter.
  • the fiber connecting the fiber adapter (such as adapter 1 and/or adapter 2) to the gain fiber is the first fiber
  • the fiber connecting the fiber adapter to the isolator or WDM is the second fiber.
  • optical fiber The difference in softening temperature between the first fiber and the second fiber is greater than the difference in softening temperature between the first fiber and the gain fiber; and/or the difference in refractive index between the first fiber and the second fiber is greater than the refraction of the first fiber and the gain fiber
  • the matrix of the first optical fiber and the matrix of the gain fiber are the same or close, that is, the matrix of the optical fiber connecting the fiber adapter and the gain fiber is the same or close to the matrix of the gain fiber.
  • the glass structure of the first optical fiber and the gain fiber are the same or close, that is, the glass structure of the optical fiber connecting the WDM and the gain fiber is the same or close to the gain fiber.
  • the first optical fiber and the gain optical fiber are connected in a fusion splicing manner, that is, there is a fusion splicing point between the first optical fiber and the gain optical fiber.
  • the optical fiber adapters (such as adapter 1 and adapter 2) are directly connected to the gain fiber.
  • the gain fiber is directly introduced into the fiber adapter, or the gain fiber is directly assembled into the fiber adapter, and there is no fusion point between the fiber adapter and the gain fiber.
  • the optical fiber connecting the optical fiber adapter to the isolator and WDM is the second optical fiber.
  • FIGS. 5 to 8 are all exemplary descriptions, and the embodiments of the present application are not limited thereto.
  • the embodiment of the present application does not limit the number of optical fiber adapters.
  • FIG. 7 or FIG. 8 may also include an optical fiber adapter, for example, only the adapter 1 or the adapter 2 is included.
  • the embodiment of the present application does not limit the form and quantity of the improved optical device.
  • only the fiber connecting the WDM or isolator and the gain fiber can be the first fiber.
  • FIG. 6 only the fiber connecting the WDM or isolator and the gain fiber can be the gain fiber.
  • Solution 1 The first optical device is connected to the gain fiber by using the first optical fiber.
  • the first optical fiber and the gain optical fiber are connected by fusion splicing.
  • the first optical device is connected to the gain fiber by the first optical fiber, which means that the pigtail of the first optical device connected to the gain fiber is the first optical fiber.
  • the first optical device includes at least one capillary tube (or optical fiber head), and at least one capillary tube (or optical fiber head) is used to introduce or assemble the first optical fiber with the coating layer removed into or assembled to the first optical device .
  • the first optical device uses the second optical fiber to connect one or more of the following: other optical devices (that is, one or more second optical devices), input optical signals, output optical signals (such as optical signals amplified by gain fibers) ).
  • the first optical device includes at least one capillary tube, and the at least one capillary tube is used for introducing or assembling the second optical fiber from which the coating layer has been stripped into the first optical device.
  • the first optical device includes at least one capillary tube.
  • the at least one capillary tube is used to introduce the first optical fiber from which the coating has been stripped into the first optical device, and does not limit the transmission direction of the optical signal in the first optical fiber. It can be used to input optical signals, can also be used to output optical signals, and can also be used to input and output optical signals at the same time; similarly, the first optical device includes at least one capillary, and the at least one capillary is used to remove the coating layer.
  • the introduction of the second optical fiber into the first optical device does not limit the transmission direction of the optical signal in the second optical fiber.
  • the second optical fiber can be used to output optical signals, can also be used to output optical signals, and can also be used to input and output optical signals. Signal.
  • the capillary that introduces the first optical fiber into the first optical device and the capillary that introduces the second optical fiber into the first optical device may be the same capillary, such as a dual-line capillary (or called a dual-line optical fiber capillary, or a dual-line optical fiber capillary). It is a dual-line optical fiber head) to introduce the first optical fiber and the second optical fiber into the first optical device; it can also be different capillaries, such as passing through two single-line capillary tubes (or called single-line optical fiber capillary, or called single-line optical fiber head). An optical fiber and a second optical fiber are introduced into the first optical device.
  • the difference in softening temperature or refractive index between the second optical fiber and the first optical fiber is greater than the difference in softening temperature or refractive index between the first optical fiber and the gain fiber.
  • the first optical device is connected to the optical fiber of another optical device (such as the second optical device), or the optical fiber of the first optical device input/output optical signal, and the optical fiber of the first optical device is connected to the gain fiber.
  • the difference in softening temperature or refractive index is greater than the difference in softening temperature or refractive index between the first optical device connected to the gain fiber and the gain fiber.
  • the first optical device uses the optical signal input from the second optical fiber to reach the first optical fiber through at least one section of free space, or the first optical device uses the optical signal input from the first optical fiber to reach the second optical fiber through at least one section of free space. That is to say, the optical signal transmitted in the optical fiber through which the first optical device is connected to other optical devices or the input optical signal, in the first optical device, reaches the optical fiber connecting the gain fiber of the first optical device through at least a section of space (ie The first optical fiber), or the optical signal transmitted in the optical fiber connecting the first optical device to the gain fiber, in the optical device, at least through a section of space to reach the first optical device to connect to other optical devices or the optical fiber output of the optical signal (ie The second fiber).
  • WDM or isolator Take WDM or isolator as an example.
  • One possible design method is to replace the fiber pigtail connecting the WDM or isolator with the gain fiber with the first fiber (for example, the fiber that is the same as or close to the gain fiber matrix) to form a fiber amplifier composed of heterogeneous fibers.
  • Example 1 as shown in Figure 5, the fiber amplifier can be composed of WDM, pump laser, isolator and gain fiber.
  • the existing heterogeneous optical fiber amplifier is improved to obtain an improved heterogeneous optical fiber amplifier.
  • the matrix of the first fiber and the gain fiber are the same or similar.
  • the fiber pigtail connecting the WDM and/or isolator and the gain fiber can be replaced with the first fiber.
  • the fiber connecting the WDM to the pump laser, the fiber inputting the optical signal, and the fiber outputting the optical signal of the isolator (that is, the optical signal amplified by the gain fiber) are still the second fiber.
  • the difference in softening temperature or refractive index between the optical fiber that WDM introduces the input optical signal (ie the second fiber) and the fiber that connects the gain fiber to WDM (ie the first fiber) is greater than that of the fiber that connects the gain fiber to WDM.
  • the difference in softening temperature or refractive index between gain fibers is greater than that of the fiber that connects the gain fiber to WDM.
  • the softening temperature or refractive index difference between the WDM fiber connected to the pump laser (ie the second fiber) and the WDM fiber connected to the gain fiber is greater than the softening temperature between the WDM fiber connected to the gain fiber and the gain fiber Or the difference in refractive index.
  • the difference in softening temperature between the optical fiber outputting the optical signal of the isolator (ie the second optical fiber) and the optical fiber connecting the isolator to the gain fiber (ie the first optical fiber) is greater than the difference between the optical fiber connecting the isolator to the gain fiber and the gain fiber.
  • the WDM shown in FIG. 5 may refer to the WDM shown in FIG. 9 below; and/or the isolator shown in FIG. 5 may refer to the isolator shown in FIG. 14 below.
  • the fiber amplifier can be composed of WDM, pump laser, isolator, one or more fiber optic adapters, and gain fiber.
  • one or more optical fiber adapters such as adapter 1 and adapter 2
  • the fiber pigtails connecting the adapter 1 and the adapter 2 to the gain fiber can be replaced with the first fiber (for example, an optical fiber that is the same as or close to the matrix of the gain fiber).
  • the optical fiber connecting the adapter 1 and the WDM, and the optical fiber connecting the adapter 2 and the isolator are all second optical fibers.
  • the matrix of the first fiber and the gain fiber are the same or close to each other.
  • the fiber pigtail connecting the adapter 1 and/or the adapter 2 and the gain fiber can be replaced with the first fiber.
  • the optical fiber connecting the adapter 1 to the WDM and the optical fiber connecting the adapter 2 to the isolator are still the second optical fiber.
  • the softening temperature difference between the optical fiber of the adapter 1 connecting the WDM fiber (ie the second fiber) and the optical fiber of the adapter 1 connecting the gain fiber (ie the first fiber) is greater than that of the optical fiber connecting the adapter 1 to the gain fiber and The difference in softening temperature between gain fibers.
  • the softening temperature difference between the fiber connecting the adapter 2 to the isolator and the fiber connecting the adapter 2 to the gain fiber is greater than the softening temperature difference between the fiber connecting the adapter 2 to the gain fiber and the gain fiber.
  • Both the existing WDM and isolator can be applied to the optical fiber amplifier shown in FIG. 7.
  • the first optical device is directly connected to the gain fiber, and there is no fusion point between the first optical device and the gain fiber.
  • the first optical device is directly connected to the gain fiber, which means that the pigtail of the first optical device connected to the gain fiber is directly the gain fiber, so there is no fusion point between the first optical device and the gain fiber.
  • the first optical device includes at least one capillary (or optical fiber head), and the at least one capillary (or optical fiber head) is used for introducing or assembling the gain fiber with the coating layer removed into or assembling the first optical device.
  • the first optical device uses the second optical fiber to connect one or more of the following: other optical devices (such as the second optical device), the input optical signal, and the output optical signal (such as the optical signal amplified by the gain fiber).
  • the first optical device includes at least one capillary tube, and the at least one capillary tube is used for introducing or assembling the second optical fiber from which the coating layer has been stripped into the first optical device.
  • the first optical device includes at least one capillary, and the at least one capillary is used to introduce the gain fiber with the coating removed into the first optical device, and does not limit the transmission direction of the optical signal in the gain fiber.
  • the gain fiber can be used for
  • the input optical signal can also be used to output optical signals, and can also be used to input and output optical signals at the same time;
  • the first optical device includes at least one capillary tube, and at least one capillary tube is used to strip the second optical fiber from the coating layer.
  • the introduction into the first optical device does not limit the transmission direction of the optical signal in the second optical fiber.
  • the second optical fiber can be used to output optical signals, can also be used to output optical signals, and can also be used to input and output optical signals at the same time.
  • the capillary that introduces the gain fiber into the first optical device and the capillary that introduces the second optical fiber into the first optical device may be the same capillary, such as through a dual-line capillary (or called a dual-line fiber capillary, or called a dual-line fiber capillary).
  • the double-line fiber head introduces the gain fiber and the second fiber into the first optical device; it can also be different capillaries, such as two single-line capillary tubes (or called single-line fiber capillary, or single-line fiber head) to connect the gain fiber and The second optical fiber is introduced into the first optical device.
  • the first optical device is connected to other optical devices or the optical fiber (that is, the second optical fiber) for input/output optical signals and the gain fiber have different softening temperatures or different refractive indexes.
  • the optical signal input by the first optical component using the second optical fiber reaches the gain fiber through at least a section of free space, or the optical signal input by the first optical component using the gain optical fiber reaches the second optical fiber through at least one section of free space. That is, the first optical device is connected to other optical devices or the optical signal transmitted in the optical fiber for input/output optical signals. In the first optical device, at least a section of space reaches the gain fiber, or the optical signal transmitted in the gain fiber In the first optical device, at least a section of space is reached to the first optical device to connect to other optical devices or the optical fiber (ie, the second optical fiber) for inputting/outputting optical signals.
  • the fiber pigtail connecting the WDM or isolator and the gain fiber can be directly replaced with a gain fiber to form a fiber amplifier composed of heterogeneous fibers.
  • the fiber amplifier can be composed of WDM, pump laser, isolator and gain fiber.
  • the existing heterogeneous optical fiber amplifier is improved to obtain an improved heterogeneous optical fiber amplifier.
  • the fiber pigtail connecting the WDM and the isolator with the gain fiber can be directly replaced with the gain fiber.
  • the optical fiber connecting the WDM and the pump laser, the optical fiber inputting the WDM optical signal, and the optical fiber outputting the isolator are all second optical fibers.
  • the first optical device is directly connected to the gain fiber, and the first optical device is connected to other optical devices or the fiber for input/output optical signals and the gain fiber have different softening temperatures or different refractive indexes.
  • WDM and/or isolators are directly connected to gain fibers.
  • the softening temperature or refractive index of the optical fiber into which the WDM introduces the input optical signal (that is, the second optical fiber) and the gain optical fiber are different.
  • the softening temperature or refractive index of the WDM fiber connecting the pump laser (ie, the second fiber) and the gain fiber are different.
  • the softening temperature or refractive index of the optical fiber (ie, the second optical fiber) from which the isolator outputs the optical signal and the gain fiber are different.
  • the WDM shown in FIG. 6 may refer to the WDM shown in FIG. 9 below; and/or the isolator shown in FIG. 6 may refer to the isolator shown in FIG. 14 below.
  • the fiber amplifier can be composed of WDM, pump laser, isolator, one or more fiber adapters, and gain fiber.
  • one or more optical fiber adapters such as adapter 1 and adapter 2
  • the fiber pigtails connecting the adapter 1 and the adapter 2 with the gain fiber can be directly replaced with the gain fiber.
  • the optical fiber connecting the adapter 1 and the WDM, and the optical fiber connecting the adapter 2 and the isolator are all second optical fibers.
  • the first optical device is directly connected to the gain fiber, and the first optical device is connected to other optical modules or the fiber for input/output optical signals and the gain fiber have different softening temperatures or different refractive indexes.
  • the adapter 1 or the adapter 2 can be directly connected to the gain fiber.
  • the softening temperature of the optical fiber (that is, the second optical fiber) connected to the WDM by the adapter 1 is different from the softening temperature of the gain optical fiber.
  • the softening temperature of the optical fiber (ie, the second optical fiber) connecting the adapter 2 to the isolator and the gain optical fiber is different.
  • Both the existing WDM and isolator can be applied to the optical fiber amplifier shown in FIG. 8.
  • solution 1 and the solution 2 are exemplarily introduced in conjunction with FIG. 5 to FIG. 8, and the embodiment of the present application is not limited thereto.
  • scheme 1 and scheme 2 can also be used in combination.
  • some optical devices use plan 1, and some optical devices use plan 2.
  • the fiber connecting the WDM and the gain fiber is the first fiber, and the isolator is directly connected to the gain fiber (or the gain fiber is directly introduced or assembled into the isolator).
  • the first optical fiber may be an optical fiber close to the softening temperature or refractive index of the gain fiber.
  • the matrix of the fiber connected to the gain fiber is the same as or close to the matrix of the gain fiber. Therefore, the heterogeneous optical fiber amplifier provided by the embodiment of the present application can greatly reduce the connection loss of the heterogeneous optical fiber.
  • Heterogeneous optical fiber connection is a universal requirement for realizing L-band optical amplifier and S-band optical amplifier. Since the spectrum effectiveness (SE) of optical transmission is close to the Shannon limit. Therefore, in order to further increase the optical fiber transmission capacity, an important direction is to expand the available spectrum, from C-band to L-band and S-band.
  • SE spectrum effectiveness
  • the gain fiber of the L and S-band optical amplifier generally uses other matrix fibers that are different from the quartz glass matrix.
  • the optical fiber on the line is a silica glass matrix fiber, and the pigtails of optical components such as WDM and isolators in the existing optical amplifier module are also silica glass matrix fibers. Therefore, L ⁇ S optical amplifiers need to realize heterogeneous fiber connection.
  • the loss at the connection of the heterogeneous fiber in the embodiment of the present application is equivalent to the loss of the fusion splicing of the silica glass matrix fiber in the existing optical amplifier (ie, fiber amplifier).
  • the loss at the connection of the heterogeneous fiber is equivalent to the loss at the connection of the fiber in the fiber amplifier composed of homogeneous fibers, for example, the loss of the fusion splicing of the silica glass matrix fiber in the existing fiber amplifier.
  • the fusion splicing loss of the quartz glass matrix fiber is about 0.1dB. If the heterogeneous fiber is spliced directly, the loss will reach 0.5dB ⁇ 1dB.
  • the heterogeneous fiber amplifier provided by the embodiment of the application can theoretically achieve a loss close to 0.1dB.
  • the splicing loss is even lower than the splicing loss of the silica glass matrix fiber.
  • the optical amplifier gain can be increased correspondingly. Assuming that an optical amplifier has four connection points, the optical amplifier gain can be roughly increased by 1.6 to 3.6 dB.
  • One of the main problems of the L/S band optical amplifier is that the gain is too small, so if the gain can increase this range, it is very important for the L/S band optical amplifier.
  • the noise figure of the optical amplifier can be reduced.
  • the connection loss before the first section of gain fiber has a greater impact on the noise figure of the optical amplifier.
  • the heterogeneous optical fiber amplifier provided by the embodiment of the present application can reduce the noise coefficient of optical amplifier by 0.4-0.9 dB compared with the existing heterogeneous optical fiber fusion splicing solution.
  • Another major problem of the L/S band is that the noise figure is relatively high. Therefore, the heterogeneous fiber amplifier provided by the embodiment of the present application is very important for realizing practical L/S band optical amplifier.
  • the optical amplifier module (including at least one first optical device) composed of heterogeneous optical fibers provided in the embodiments of the present application can minimize the connection loss of heterogeneous optical fibers, which helps to increase optical amplifier gain, reduce noise figure, and reduce processing. Difficulty and cost reduction are expected to become necessary technologies for L/S-band optical amplifiers.
  • optical fiber amplifier provided by the embodiment of the present application is described above, and the various optical devices that can form the optical fiber amplifier are described below. It should be understood that the various optical devices described below can be used alone, or in combination, or can also be used in the optical fiber amplifiers described in FIGS. 4 to 8.
  • the WDM applicable to the embodiment of the present application is introduced with reference to FIG. 9.
  • the WDM may be the first optical device described in the embodiment in FIG. 4.
  • the WDM shown in Fig. 9 can be used in the optical fiber amplifiers described in Figs. 4 to 8.
  • FIG. 9 shows a schematic diagram of WDM applicable to the embodiments of the present application.
  • the WDM may include one or more lenses, such as lens 1 and lens 2.
  • the WDM may also include a WDM diaphragm, a single-line capillary (such as a single-line capillary 1), and a double-line capillary (such as a dual-line capillary 1).
  • the single-line capillary may also be called a single-line optical fiber capillary, and those skilled in the art should understand its meaning, for example, it may also be replaced with a single-line optical fiber head.
  • the dual-line capillary for example, may also be called a dual-line optical fiber capillary, and those skilled in the art should understand its meaning. For example, it may also be replaced with a dual-line optical fiber head. The following is unified, and both single-line capillary and double-line capillary are used.
  • the embodiment of the present application may adopt WDM of the spatial optical path.
  • WDM of the spatial optical path.
  • other types of WDM can also be used, which is not limited.
  • the WDM module can be used to complete the function of signal light and pump light combining or multiplexing. As shown in Figure 9, the signal light is sent to the WDM diaphragm via the second optical fiber, and the pump light is also sent to the WDM diaphragm via the second optical fiber.
  • the WDM diaphragm can complete the combination or multiplexing of signal light and pump light to form mixed light.
  • the mixed light is only a naming for distinguishing, and the mixed light may also be called a multiplexed light, and its naming does not limit the protection scope of the embodiments of the present application. In the following, it is uniformly expressed by mixed light.
  • the single-line capillary 1 inputs an optical signal from the second optical fiber (that is, the signal light input optical fiber), and sends it to the lens 1.
  • the optical signal in the input optical signal is a general optical signal, which means that the optical signal is introduced or introduced or input, that is, the optical signal input by the second optical fiber is signal light.
  • the second optical fiber can be stripped of the coating layer, inserted into a capillary, and then ground into a bevel and coated.
  • the lens 1 mainly collimates the light beam of the optical signal sent by the single-line capillary 1 (here, the light beam of the signal light).
  • the single-line capillary 1 sends the signal light into the space, and the signal light diverges in the space. Therefore, after collimating by the lens 1, the signal light can be turned into parallel light or nearly parallel light.
  • the WDM diaphragm mainly realizes the multiplexing or combining of the signal light sent by lens 1 and the pump light sent by lens 2.
  • FIG. 10 A possible implementation is shown in Figure 10.
  • the substrate is coated with a multilayer film, the pump light from lens 2 is incident through the multilayer film, the signal light from lens 1 is incident through the substrate, and the mixed light generated after multiplexing is emitted to lens 2 through the multilayer film.
  • the pump light is sent through the single-line capillary 1 and the signal light is sent through the double-line capillary 1.
  • the WDM in FIGS. 5 and 6 is WDM used to provide forward pumping.
  • WDM can also be used to provide backward pumping, and the embodiment of the present application is not limited thereto.
  • WDM is used to provide backward pumping
  • the structure of WDM is similar to that of forward pumping (see Figure 9).
  • Signal light is output, pump light is input, and mixed light has both input and output. Regardless of whether it is a forward-pumped WDM or a backward-pumped WDM, the working principle is similar, so the implementation schemes of the two are also similar, and will not be repeated.
  • the hybrid optical output fiber in WDM is the first fiber (solution 1) or the gain fiber (solution 2), and the signal light input fiber and the pump light input fiber are the second fiber.
  • the beams of the mixed light and pump light can be adjusted or collimated by any of the following methods.
  • Method 1 Adjust the angle between the two optical fibers in the dual-line capillary, so that the two optical fibers in the dual-line capillary are not parallel, so as to collimate the beam of the pump light and the beam of the mixed light.
  • the WDM in Figure 9 is a WDM that supports forward pumping.
  • the main function of the dual-line capillary 1 includes: Introduce pump light from the pump light input fiber (ie the second fiber) and send it to the lens 2. And receive the mixed light sent from the lens 2 and send it to the mixed light output fiber (first fiber or gain fiber). Or the signal light is introduced from the signal light input fiber (ie, the second fiber), sent to the lens 2, and received the mixed light sent from the lens 2, and sent to the mixed light output fiber.
  • the main functions of the dual-line capillary 1 include: introducing pump light from the pump light input fiber (ie the second fiber), sending it to the lens 2, and outputting the mixed light from the lens 2 Part of the mixed light of the optical fiber (first fiber or gain fiber) is sent from the lens 2 to the mixed light output fiber, and some is sent from the mixed light output fiber to the lens 2.
  • the "mixed light output fiber” is just a The name does not represent the transmission direction of the optical signal in the optical fiber; or the signal light is introduced from the signal light input fiber (ie the second fiber), sent to the lens 2, and from the lens 2 to the mixed light output fiber (the first fiber or gain fiber) ) Part of the mixed light is sent from the lens 2 to the mixed light output fiber, and some is sent from the mixed light output fiber to the lens 2.
  • the "mixed light output fiber” is just a name, and does not represent the optical fiber. Optical signal transmission direction.
  • the angle between the two fibers in the dual-line capillary can be designed according to the refractive index of the first fiber or the gain fiber, so as to collimate the beam of mixed light.
  • the hybrid light output fiber first fiber or gain fiber
  • the hybrid light output fiber first fiber or gain fiber
  • the pump light input fiber/signal light input fiber second fiber
  • the included angle of the optical fiber makes the mixed light beam align with the corresponding position of the WDM diaphragm.
  • the two beams are parallel in the lens, that is, the refraction angle ⁇ 1 of the two beams through the free space to the lens is the same.
  • the refractive index of each part of the lens is the same, the refraction angle of the two beams from the lens 2 to the free space and the refraction angle ⁇ 2 from the free space to the double-line capillary are the same.
  • ⁇ 2 can be set according to the best incident angle/exit angle of the WDM diaphragm, the structure and optical parameters of the WDM diaphragm, lens, and double-line capillary, so that the value in the double-line capillary 1 can be calculated according to the above formula.
  • the angle between the first fiber/gain fiber and the second fiber is the best incident angle/exit angle of the WDM diaphragm, the structure and optical parameters of the WDM diaphragm, lens, and double-line capillary, so that the value in the double-line capillary 1 can be calculated according to the above formula. The angle between the first fiber/gain fiber and the second fiber.
  • Method 2 Adjust the light beams of the optical signals in the two fibers in the double-line capillary through the lens, for example, adjust the light spot or mode spot of the optical signal input or output from the two fibers in the double-line capillary through the lens, so as to collimate the pump light Light beam and mixed light beam, and/or the light spot or mode spot (including the size of the light spot or mode spot, and/or the size of the light spot or mode spot on the WDM film in the two optical fibers in the aligned double-line capillary Divergence angle, etc.).
  • the lens can mainly realize the collimation of the spatial light path, and at the same time can adjust the beam spot or mode spot, for example, realize the collimation of beams with different diameters and/or different divergence angles until they have the same or similar spot or mode spot size parallel (Or nearly parallel) on the beam.
  • the lens that is, the lens 2 in FIG. 9) may be a lens supporting dual optical paths.
  • a possible design can use an aspherical C lens, as shown in Figure 12.
  • the C lens (ie, lens 2 in FIG. 9) has a small radius of curvature in the upper half and a large radius of curvature in the lower half.
  • the radius of curvature of the C lens corresponding to the mixed optical path that is, corresponding to the first fiber or gain fiber
  • the radius of curvature of the C lens corresponding to the pump light path that is, to the second fiber.
  • the size of the radius of curvature is relative, that is, the radius of curvature of the upper part is relatively small relative to the radius of curvature of the lower part.
  • the value of the radius of curvature of the upper and lower parts is not limited.
  • the portion occupied by the curved surface with a small radius of curvature and the portion occupied by the curved surface with a large radius of curvature are not limited. As long as the radius of curvature of the optical path of the corresponding mixed light is smaller than the radius of curvature of the optical path of the corresponding pump light, it is applicable to the embodiments of the present application.
  • the change in refractive index of the upper half of the G lens (ie lens 2 in FIG. 9) in the radial direction is faster than that of the lower half of the refractive index in the radial direction.
  • the G lens corresponding to the optical path of the mixed light that is, the optical path corresponding to the first fiber or the gain fiber
  • Optical path) changes in refractive index along the radial direction.
  • the G lens provided by the embodiment of the present application is more flexible and has more application scenarios.
  • the speed of the refractive index change along the radial direction is relative, that is, the refractive index change of the upper part in the radial direction is relatively faster than the refractive index change of the lower part in the radial direction.
  • the value of the refractive index changes along the radial direction of the upper and lower parts is not limited.
  • a lens such as aspheric C lens or asymmetric G lens, can be used to align the beams of different matrix fibers, and/or align the beams of different matrix fibers at a selected position ( For example, the light spot or mode spot (including the size of the light spot or the mode spot, and/or the divergence angle of the light spot or the mode spot, etc.) on the surface of the WDM diaphragm, that is, the light beam of the optical signal in the first fiber or the gain fiber (such as The beam of mixed light) and the beam of the optical signal in the second fiber (such as the beam of pump light), and/or the beam of the optical signal in the first fiber or the gain fiber and the beam of the optical signal in the second fiber are adjusted The mold spot or light spot.
  • the light spot or mode spot including the size of the light spot or the mode spot, and/or the divergence angle of the light spot or the mode spot, etc.
  • the optical signal spot or mode spot (including the size of the spot or mode spot, and/or the divergence angle) may be the same or different. The following mainly introduces the case of different optical signal mode spots.
  • the mode spot of the hybrid light output fiber may be smaller than the mode spot of the pump light input fiber (second fiber), that is, ⁇ 3 ⁇ 1; and/or, the mode spot of the hybrid light output fiber
  • the mode spot may be smaller than the mode spot of the signal light input fiber (second fiber), that is, ⁇ 3 ⁇ 2.
  • the mode spot of the WDM diaphragm receiving the pump light and the mode spot of the mixed light output by the WDM diaphragm should be the same or similar, that is, ⁇ 4 ⁇ 5.
  • the double-line capillary 1 in the embodiment of the present application has a smaller optical fiber mode spot corresponding to the optical path of the mixed light than that of the optical path of the corresponding pump light, that is, ⁇ 3 ⁇ 2.
  • Example 1 the mode spot of the lens (ie, the lens 2) supporting the mixed light path is different from the mode spot of the pump light path.
  • the lens can be designed according to the mode spot of the mixed light path and the mode spot of the pump light path.
  • the curvature radius or refractive index distribution of the lens can be designed to adjust its focal length.
  • the lens may be the lens shown in FIG. 12 or FIG. 13.
  • a lens such as an aspheric C lens or an asymmetric G lens, can be used, and the optical fiber mode spot supporting the mixed optical path is different from the optical fiber mode spot corresponding to the pumping optical path.
  • Example 2 Design a dual-line capillary (ie, dual-line capillary 1) to support that the mode spot of the mixed light path is different from the mode spot of the pump light path.
  • a double-line capillary can be designed according to the mode spot of the mixed light path and the mode spot of the pump light path.
  • the position of the double-line capillary can be designed to align the focal point of the lens.
  • the bidirectional capillary 1 can peel off the coating layer of the mixed light output fiber (first fiber or gain fiber) and pump light input fiber (second fiber), insert it into the capillary, and then grind it into a bevel and coat it.
  • Example 3 adjust the pump light input fiber (second fiber). For example, a silica glass matrix fiber that matches the mode spot of the hybrid light output fiber (first fiber or gain fiber) is selected as the pump light input fiber.
  • the WDM provided in the embodiments of the present application can be used to change the connection mode of the WDM and the gain fiber in the optical fiber amplifier.
  • the butt connection of WDM and gain fiber can be changed to the butt connection of homogeneous fiber (or close to homogeneous fiber) (that is, scheme 1, if the first fiber is the same or close to the matrix of the gain fiber, or, The refractive index and/or softening temperature of the first fiber and the gain fiber are close to each other), or there is no need to connect at all (that is, the WDM is directly connected to the gain fiber), so that the problems caused by heterogeneous fiber fusion can be avoided.
  • the WDM applicable to the embodiments of the present application is described above in conjunction with FIG. 9 to FIG. 13.
  • an isolator suitable for the embodiment of the present application will be introduced in conjunction with FIG. 14.
  • the isolator may be the first optical device described in the embodiment of FIG. 4.
  • the isolator shown in Fig. 14 can be used in the optical fiber amplifiers described in Figs. 4-8.
  • the isolator shown in FIG. 14 and the WDM shown in FIG. 9 can be used separately or in combination.
  • Fig. 14 shows a schematic diagram of an isolator suitable for embodiments of the present application.
  • the isolator may include one or more lenses, such as lens 3 and lens 4.
  • the isolator may also include an optical isolator central device and at least one single-line capillary (such as single-line capillary 2 and single-line capillary 3).
  • the optical isolation center device may include, for example, a wedge-shaped birefringent crystal (such as a wedge-shaped birefringent crystal 1 and a wedge-shaped birefringent crystal 2) and a Faraday rotator.
  • the isolator is used to allow the optical signal transmitted in one direction to pass through or to allow the optical signal transmitted in one direction to have a small loss, while the optical signal transmitted in the opposite direction cannot pass or has a large loss.
  • the isolator can be used to suppress the transmission of possible reflected light after the output fiber (for example, the amplified signal light output fiber in FIG. 14).
  • the amplified signal light is sent to the central part of the optical isolator through the amplified signal light input fiber (first fiber or gain fiber), and then sent to the amplified signal light output fiber (second fiber).
  • the possible reflected light after the amplified signal light output fiber can be sent to the optical isolator center piece through the amplified signal light output fiber, but cannot be sent to the amplified signal light input fiber after passing through the optical isolator center piece, thereby suppressing possible reflected light The reverse transmission.
  • the single-line capillary 2 introduces the amplified signal light from the first fiber or gain fiber (that is, the amplified signal light input fiber), and sends it to the lens 3.
  • a possible implementation is to strip the coating of the first optical fiber or the gain optical fiber, insert it into a capillary, and then grind it into a bevel and coat it.
  • the lens 3 mainly collimates the signal light sent by the single-line capillary 2.
  • the single-line capillary tube 2 sends the signal light into the space, and the signal light diverges in the space. Therefore, after collimating by the lens 3, the signal light can be turned into parallel light or nearly parallel light.
  • the central piece of the optical isolator can be used to realize the one-way transmission of optical signals.
  • the optical isolator center piece sends the amplified signal light received from lens 3 to lens 4, and at the same time transmits the possible reflected light from the lower section of lens 4 away from the single-line capillary 2 to lens 3.
  • the direction of the light path is sent to lens 3. Due to the deviation of the direction, the lens 3 cannot couple it into the amplified signal light input fiber after receiving the possible reflected light from the lower section.
  • the central piece of the optical isolator can be composed of two wedge-shaped birefringent crystals, a magnet, and a Faraday rotator made of yttrium iron garnet.
  • the lens 4 After the lens 4 receives the amplified signal light from the central piece of the optical isolator, it sends it to the single-line capillary 3, and finally outputs it through the amplified signal light output fiber (ie, the second fiber).
  • the amplified signal light output fiber ie, the second fiber.
  • the function and implementation of this part are similar to the amplifying signal light input fiber, the single-line capillary 2 and the lens 3, but the direction is opposite. I won't repeat them here.
  • the amplified signal light input fiber is the first fiber (solution 1) or the gain fiber (solution 2)
  • the amplified signal light output fiber is the second fiber.
  • the amplified signal light beam can be adjusted or collimated by any of the following methods.
  • Method 1 Adjust the angle between the single-line capillary 2 and the optical fibers in the single-line capillary 3 so that the single-line capillary 2 and the optical fibers in the single-line capillary 3 are not parallel, so as to collimate the amplified signal light beam.
  • the angle between the single-line capillary 2 and the optical fiber in the single-line capillary 3 can be adjusted by the refractive index of the first fiber or the gain fiber and the refractive index of the second fiber, so as to collimate or adjust the beam of the amplified signal light. .
  • the position of the amplified signal light input fiber in the single-line capillary 2 can be adjusted to collimate the amplified signal light beam, such as making the amplified signal light beam Align the corresponding position of the center piece of the optical isolator.
  • Method 2 Adjust the optical signal beam of the optical fiber in the single-line capillary through the lens, for example, adjust the optical signal spot or mode spot of the optical fiber in the single-line capillary through the lens, so as to collimate the amplified signal light beam and/or align the single line
  • the optical signal of the optical fiber in the capillary 2 and the optical signal of the optical fiber in the single-line capillary 3 The spot or mode spot on the isolator middle part (including the size of the spot or mode spot, and/or the divergence angle of the spot or mode spot, etc.) .
  • the lens 3 in the isolator is used to collimate and/or adjust the optical signal beam of the optical fiber in the single-line capillary 2 (the optical signal beam of the first fiber or the gain fiber), and the lens in the isolator 4 is used to collimate and/or adjust the light beam of the optical signal of the optical fiber in the single-line capillary 3 (the light beam of the optical signal of the second optical fiber).
  • the focal length of lens 3 is smaller than the focal length of lens 4.
  • the optical signal spot or mode spot (including the size of the spot or mode spot, and/or the divergence angle) may be the same or different. The following mainly introduces the case of different optical signal mode spots.
  • the mode spot of the amplified signal light input fiber may be smaller than the mode spot of the amplified signal light output fiber (second fiber), that is, ⁇ 6 ⁇ 7.
  • the mode spot ⁇ 8 of the optical isolator center piece receiving the amplified signal light is related to the mode spot ⁇ 9 of the optical isolator center piece sending the amplified signal light, and ⁇ 9 is related to ⁇ 7.
  • Example 1 the lens (such as lens 3) supports the mode spot of the amplified signal light output fiber to be different from the mode spot of the amplified signal light input fiber.
  • the lens 3 can be designed according to the mode spot of the amplified signal light output fiber and the amplified signal light input fiber.
  • the curvature radius or refractive index distribution of the lens 3 can be designed.
  • a lens can be used to support different modes of the amplified signal light output fiber and the amplified signal light input fiber.
  • Example 2 Design a single-line capillary (such as single-line capillary 2 and single-line capillary 3) to support that the mode spot of the amplified signal light output fiber is different from the mode spot of the amplified signal light input fiber.
  • a single-line capillary such as single-line capillary 2 and single-line capillary 3
  • the single-line capillary tube 2 and the single-line capillary tube 3 can be designed according to the mode spots of the amplified signal light output fiber and the amplified signal light input fiber to align the corresponding position of the central part of the optical isolator.
  • the positions of single-line capillary 2 and single-line capillary 3 can be designed.
  • Example 3 Adjust the output fiber (second fiber) of the amplified signal light.
  • a silica glass matrix fiber that matches the mode spot of the amplified signal light input fiber (first fiber or gain fiber) is selected as the amplified signal light output fiber.
  • the connection mode of the isolator and the gain fiber in the optical fiber amplifier can be changed.
  • the butt joint between the isolator and the gain fiber can be turned into a butt joint of a homogenous fiber (or close to a homogenous fiber) (Scheme 1, for example, the first fiber is the same or close to the matrix of the gain fiber, or , The refractive index and/or softening temperature of the first fiber is close to that of the gain fiber), or no docking is required at all (that is, the isolator is directly connected to the gain fiber), so that the problems caused by heterogeneous fiber fusion can be avoided.
  • the WDM suitable for the embodiment of the present application is described above in conjunction with FIGS. 9 to 13, the isolator suitable for the embodiment of the present application is described in conjunction with FIG. 14, and the optical fiber adapter suitable for the embodiment of the present application is described below in conjunction with FIG. 15.
  • the optical fiber adapter may be the first optical device described in the embodiment in FIG. 4.
  • the optical fiber adapter shown in Figure 15 can be used in the optical fiber amplifiers described in Figures 4 to 8.
  • the optical fiber adapter shown in FIG. 15 can be used alone or in combination with the WDM shown in FIG. 9 and the isolator shown in FIG. 14.
  • Fig. 15 shows a schematic diagram of an optical fiber adapter suitable for an embodiment of the present application.
  • the optical fiber adapter may include one or more lenses, such as lens 5 and lens 6.
  • the optical fiber adapter may also include at least one single-line capillary, such as a single-line capillary 4 and a single-line capillary 5.
  • the optical fiber adapter may also be denoted as a heterogeneous optical fiber adapter or an adapter, for example.
  • the optical fiber adapter may be the adapter 1 shown in FIG. 7 or FIG. 8 or the adapter 2 shown in FIG. 7 or FIG. 8.
  • the optical fiber adapter is used to connect the first optical fiber and the second optical fiber, or the optical fiber adapter is used to connect the second optical fiber and the gain optical fiber.
  • Optical fiber adapters can be used to realize spatial coupling of optical fibers with different refractive indexes or softening temperatures, thereby reducing the loss of optical fiber connections.
  • the optical signal in Figure 15 can be input from optical fiber 1 and output from optical fiber 2; or, the optical signal in Figure 15 can also be input from optical fiber 2 and output from optical fiber 1.
  • the optical fiber 1 is a first optical fiber or a gain optical fiber, and the optical fiber 2 is a second optical fiber; or, the optical fiber 2 is a first optical fiber or a gain optical fiber, and the optical fiber 1 is a second optical fiber.
  • the optical fiber 1 may be the second optical fiber
  • the optical fiber 2 may be the first optical fiber
  • the optical fiber 1 may be the first optical fiber
  • the optical fiber 2 may be the second optical fiber
  • the optical fiber 1 may be the second optical fiber
  • the optical fiber 2 may be the gain optical fiber
  • the optical fiber 1 may be a gain fiber
  • the optical fiber 2 may be a second optical fiber
  • a possible process is that the optical signal is input from the optical fiber 1, and the single-line capillary 4 introduces the optical signal from the optical fiber 1 and sends it to the lens 5.
  • the lens 5 collimates the optical signal and sends it to the lens 6.
  • the lens 6 couples the optical signal into the single-line capillary 5 and the optical fiber 2.
  • the light beam of the optical signal of the optical fiber in the single-line capillary is adjusted through the lens, for example, the optical signal spot or the mode spot of the optical signal of the optical fiber in the single-line capillary is adjusted through the lens, so as to collimate the light beam of the optical signal (the beam of the amplified signal light) ), and/or align the optical signal of the optical fiber in the single-line capillary 4 and the optical signal of the optical fiber in the single-line capillary 5 in the spot or mode spot between the lens 5 and the lens 6 (including the size of the spot or mode spot, and/or The divergence angle of the light spot or the mold spot, etc.).
  • the focal length of the lens used to introduce the first optical fiber or the gain fiber into the optical fiber adapter is smaller than the focal length of the lens used to introduce the second optical fiber into the optical fiber adapter.
  • a lens (such as lens 5 or lens 6) supports that the mode spot of the optical fiber 1 is different from the mode spot of the optical fiber 2.
  • a single-line capillary (such as a single-line capillary 4 or a single-line capillary 5) is designed to support that the mode spot of the optical fiber 1 is different from the mode spot of the optical fiber 2.
  • the single-line capillary 4 please refer to the single-line capillary 2 shown in FIG. 14 and the single-line capillary 5 may refer to the single-line capillary 3 shown in FIG. Lens 4, I will not repeat it here.
  • the single-line capillary 5 refer to the single-line capillary 2 shown in FIG. 14 and the single-line capillary 4 may refer to the single-line capillary 3 shown in FIG. 14, and the lens 6 may refer to the lens 3 shown in FIG. The illustrated lens 4 will not be repeated here.
  • the optical fiber adapter provided in the embodiment of the present application can be used to change the connection mode of each optical module and the gain fiber in the optical fiber amplifier.
  • the butt connection of the fiber adapter and the gain fiber can be turned into the butt connection of the homogenous fiber (or close to the homogenous fiber) (that is, scheme 1, if the first fiber is the same or close to the matrix of the gain fiber, Alternatively, the refractive index and/or softening temperature of the first fiber and the gain fiber are close to each other), or there is no need for docking at all (that is, the optical fiber adapter is directly connected to the gain fiber).
  • the butt connection between the fiber optic adapter and the WDM or isolator can be turned into a homogenous fiber (or close to the homogenous fiber).
  • the matrix of the fiber connecting the fiber adapter and the WDM or isolator is the same as the matrix of the second fiber
  • there is no need for docking at all that is, the optical fiber connected to the WDM or isolator is the second optical fiber
  • WDM, isolators, and fiber optic adapters are used as examples for exemplification, which is not limited.
  • the optical fibers connecting the optical devices to different optical modules (or optical devices) are not completely the same, it is applicable to the embodiments of the present application.
  • the optical device is directly connected to the gain fiber, and the fiber that connects to other optical devices or input/output optical signals is a fiber different from the gain fiber.
  • the optical device uses the first optical fiber to connect to the gain fiber, and uses an optical fiber different from the first optical fiber to connect to other optical devices or to input/output optical signals.
  • the device embodiments (such as optical devices, fiber amplifiers) applicable to the embodiments of the present application are described above with reference to FIGS. 4 to 15.
  • the method embodiments of the present application are described in detail below with reference to FIGS. 16 to 19.
  • the description on the device side and the description of the method correspond to each other, and repeated descriptions are appropriately omitted for brevity.
  • FIG. 16 is a schematic flowchart of a method for manufacturing an optical device according to an embodiment of the present application.
  • the optical device obtained based on the method 1600 in FIG. 16 may be the first optical device mentioned above (the first optical device in scheme 1), or it may also be used in the optical fiber amplifier mentioned above (the optical fiber amplifier in scheme 1). )middle.
  • the method 1600 may include the following steps.
  • a second optical fiber to connect to one or more second optical devices, and/or use a second optical fiber to input optical signals or output optical signals amplified by gain fibers, where the softening temperature of the first optical fiber and the second optical fiber And/or the refractive index is different.
  • the difference (or absolute value of the difference) between the softening temperature of the first fiber and the second fiber is greater than the difference (or the absolute value of the difference) between the softening temperature of the first fiber and the gain fiber.
  • the refractive index difference (or absolute value of the difference) between the first fiber and the second fiber is greater than the refractive index difference (or the absolute value of the difference) between the first fiber and the gain fiber.
  • the matrix of the first fiber is the same as the matrix of the gain fiber.
  • the optical signal input through the second optical fiber reaches the first optical fiber through at least a section of free space; or, the optical signal input through the first optical fiber reaches the second optical fiber through at least one section of free space.
  • the first optical fiber and/or the second optical fiber from which the coating has been stripped is introduced into or assembled to the optical device through at least one capillary tube.
  • the first optical fiber and the gain optical fiber are connected by fusion splicing.
  • the optical device is any one or more of the following: a wavelength division multiplexer WDM, an isolator, and an optical fiber adapter.
  • the optical device is WDM.
  • WDM includes a double-wire capillary. Two optical fibers are introduced into the WDM through the double-wire capillary; one of the two optical fibers is the first optical fiber; the other of the two optical fibers is the first optical fiber. Two optical fibers. The other optical fiber of the two optical fibers is used for connecting a pump laser, or for inputting optical signals, or for outputting optical signals amplified by the gain fiber.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the WDM includes a first lens, and the light beams of the optical signals in the two optical fibers in the double-line capillary are adjusted by the first lens.
  • the radius of curvature of the first lens corresponding to the curved portion of the optical path of the optical signal in the first optical fiber is smaller than the curvature radius of the curved portion of the optical path of the optical signal in the second optical fiber corresponding to the first lens; or, the first lens
  • the change in the radial refractive index of the optical path corresponding to the optical signal in the first optical fiber is faster than the change in the radial refractive index of the optical path corresponding to the optical signal in the second optical fiber by the first lens.
  • the first lens supports different modes of optical signals in the two optical fibers in the dual-line capillary.
  • the mode spots of the optical signals in the two optical fibers in the dual-line capillary match.
  • the optical device is an isolator
  • the isolator includes a first single-line capillary tube and a second single-line capillary tube.
  • the first single-line capillary tube introduces the first optical fiber into the isolator
  • the second single-line capillary tube introduces the second optical fiber into the isolator.
  • optical fiber in the first single-line capillary and the optical fiber in the second single-line capillary are not parallel.
  • the isolator includes a second lens and a third lens.
  • the optical signal beam of the optical fiber in the first single-line capillary is adjusted by the second lens, and the optical signal beam of the optical fiber in the second single-line capillary is adjusted by the third lens. .
  • the focal length of the second lens is smaller than the focal length of the third lens.
  • the optical device is an optical fiber adapter.
  • the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube. Fiber optic adapter.
  • optical fiber in the third single-line capillary and the optical fiber in the fourth single-line capillary are not parallel.
  • the optical fiber adapter includes a fourth lens and a fifth lens.
  • the fourth lens adjusts the light beam of the optical signal of the optical fiber in the third single-line capillary
  • the fifth lens adjusts the optical signal of the optical fiber in the fourth single-line capillary. beam.
  • the focal length of the fourth lens is smaller than the focal length of the fifth lens.
  • FIG. 17 is a schematic flowchart of a method for manufacturing an optical device according to another embodiment of the present application.
  • the optical device obtained based on the method 1700 of FIG. 17 may be the first optical device mentioned above (the first optical device in scheme 2), or it may also be used in the optical fiber amplifier mentioned above (the optical fiber amplifier in scheme 2). )middle.
  • the method 1700 may include the following steps.
  • the gain fiber is used to amplify the optical signal
  • a second optical fiber is used to connect to one or more second optical devices, and/or the second optical fiber is used to input optical signals or output optical signals amplified by the gain fiber, wherein the softening temperature of the second optical fiber and the gain fiber is equal to / Or the refractive index is different.
  • the optical signal input through the second optical fiber reaches the gain fiber through at least a section of free space; or the optical signal input through the gain fiber reaches the second optical fiber through at least one section of free space.
  • the coated gain fiber and/or the second fiber are introduced into or assembled to the optical device through at least one capillary tube.
  • the optical device is any one or more of the following: a wavelength division multiplexer WDM, an isolator, and an optical fiber adapter.
  • the optical device is WDM
  • WDM includes a dual-line capillary, two fibers are introduced into the WDM through the dual-line capillary; one of the two fibers is a gain fiber; the other of the two fibers is a second fiber Fiber, the other fiber of the two fibers: used to connect a pump laser, or used to input optical signals, or used to output optical signals amplified by the gain fiber.
  • the two optical fibers in the dual-line capillary are not parallel.
  • the WDM includes a first lens, and the light beams of the optical signals in the two optical fibers in the double-line capillary are adjusted by the first lens.
  • the first lens corresponds to the curvature radius of the curved part of the optical path of the optical signal in the gain fiber, which is smaller than the curvature radius of the first lens corresponds to the curved part of the optical path of the optical signal in the second optical fiber; or, the first lens corresponds to The change of the radial refractive index of the optical path of the optical signal in the gain fiber is faster than the change of the radial refractive index of the optical path of the optical signal in the second optical fiber corresponding to the first lens.
  • the first lens supports different modes of optical signals in the two optical fibers in the dual-line capillary.
  • the mode spots of the optical signals in the two optical fibers in the dual-line capillary match.
  • the optical device is an isolator.
  • the isolator includes a first single-line capillary tube and a second single-line capillary tube.
  • the gain fiber is introduced into the isolator through the first single-line capillary tube, and the second optical fiber is introduced into the isolator through the second single-line capillary tube.
  • optical fiber in the first single-line capillary and the optical fiber in the second single-line capillary are not parallel.
  • the isolator includes a second lens and a third lens.
  • the optical signal beam of the optical fiber in the first single-line capillary is adjusted by the second lens, and the optical signal beam of the optical fiber in the second single-line capillary is adjusted by the third lens. .
  • the focal length of the second lens is smaller than the focal length of the third lens.
  • the optical device is an optical fiber adapter.
  • the optical fiber adapter includes a third single-line capillary tube and a fourth single-line capillary tube.
  • the gain fiber is introduced into the optical fiber adapter through the third single-line capillary tube, and the second optical fiber is introduced into the optical fiber adapter through the fourth single-line capillary tube.
  • Adapters are used to implement the optical fiber adapter.
  • optical fiber in the third single-line capillary and the optical fiber in the fourth single-line capillary are not parallel.
  • the optical fiber adapter includes a fourth lens and a fifth lens.
  • the fourth lens adjusts the light beam of the optical signal of the optical fiber in the third single-line capillary
  • the fifth lens adjusts the optical signal of the optical fiber in the fourth single-line capillary. beam.
  • the focal length of the fourth lens is smaller than the focal length of the fifth lens.
  • FIG. 18 is a schematic flowchart of a method for manufacturing an optical fiber amplifier according to an embodiment of the present application.
  • the optical fiber amplifier obtained based on the method 1800 of FIG. 18 may be the optical fiber amplifier mentioned above (the optical fiber amplifier in scheme 1).
  • the method 1800 may include the following steps.
  • a second optical fiber is used to connect the first optical device and one or more second optical devices, and/or the second optical fiber is used to input optical signals or output optical signals amplified by gain fibers, where the first optical fiber and the second optical fiber The softening temperature and/or refractive index of the optical fiber are different.
  • the first optical device is the first optical device mentioned above, and will not be repeated here.
  • FIG. 19 is a schematic flowchart of a method for manufacturing an optical fiber amplifier according to another embodiment of the present application.
  • the fiber amplifier obtained based on the method 1900 of FIG. 19 may be the aforementioned fiber amplifier (the fiber amplifier in Scheme 2).
  • the method 1900 may include the following steps.
  • a second optical fiber is used to connect the first optical device and one or more second optical devices, and/or the second optical fiber is used to input optical signals or output optical signals amplified by the gain fiber, wherein the second optical fiber and the gain fiber The softening temperature and/or refractive index are different.
  • the first optical device is the first optical device mentioned above, and will not be repeated here.
  • the computer program product includes one or more computer instructions.
  • the computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.
  • the computer can be a personal computer, a server, or a network device.
  • Computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium.
  • computer instructions can be transmitted from a website, computer, server, or data center through a cable (such as Coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) to transmit to another website site, computer, server or data center.
  • a cable such as Coaxial cable, optical fiber, digital subscriber line (DSL)
  • wireless such as infrared, wireless, microwave, etc.

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Abstract

一种构成光纤放大器的光器件、光纤放大器以及制造方法。光器件采用第一光纤与增益光纤连接，或者，光器件直接连接增益光纤；光器件采用第二光纤与光纤放大器中的一个或多个第二光器件连接，和/或，采用第二光纤输入光信号或输出增益光纤放大后的光信号；其中，第一光纤和第二光纤的软化温度和/或折射率不同，或者，增益光纤和第二光纤的软化温度和/或折射率不同。根据需求设计光器件的尾纤，可以提高光纤放大器的应用灵活性，提高光纤放大器的使用性能，大大降低光纤连接处的损耗，进而提升光放增益。

Description

构成光纤放大器的光器件、光纤放大器以及制造方法
本申请要求于2020年6月4日提交中国国家知识产权局、申请号为202010497761.8、申请名称为“构成光纤放大器的光器件、光纤放大器以及制造方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及通信领域，并且更具体地，涉及一种构成光纤放大器的光器件、光纤放大器以及制造方法。
背景技术
在光纤通信网络中，常用的光纤放大器中的增益光纤是石英玻璃基质掺铒光纤，光纤放大器中的波分复用器(wavelength division multiplexer，WDM)以及隔离器等光器件的尾纤都是石英玻璃基质光纤，即两者基质相同。由于都是石英玻璃基质光纤，两者软化温度和折射率相近，因此WDM及隔离器的尾纤和增益光纤熔接时比较容易，熔接性能指标也比较好。
在一些宽谱光纤放大器中，为了提高光信号的增益，可以采用其他基质的增益光纤。例如，采用一些软玻璃光纤，如碲基掺铒光纤(在碲酸盐玻璃光纤中掺铒)、氟化物掺铥光纤(氟化物玻璃光纤中掺铥)等。这些增益光纤和石英玻璃基质光纤(即光器件的尾纤)熔接比较困难，性能指标较差，故光纤放大器性能较低。
发明内容
本申请提供一种构成光纤放大器的光器件、光纤放大器以及制造方法，可以根据需求设计光器件的尾纤，从而可以提高光纤放大器的应用灵活性，提高光纤放大器的使用性能。如在某些设计中，可以大大降低光纤连接处的损耗，进而提升光放增益、降低噪声系数、降低加工难度、降低成本，提高异质光纤构成的光纤放大器的性能。
第一方面，提供了一种光器件。该光器件应用于光纤放大器中，该光器件，采用第一光纤与增益光纤连接，所述增益光纤用于放大光信号；所述光器件，采用第二光纤与所述光纤放大器中的一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同。
基于上述技术方案，应用于光纤放大器中的光器件，连接增益光纤的光纤、与连接其他光器件(如记为第二光器件)或者输入光信号或者输出光信号(如增益光纤放大后的光信号)的光纤，折射率和/或软化温度不同。一方案中，光器件可以采用第一光纤与增益光纤连接，光器件可以采用第二光纤与其他光器件连接、或者输入光信号或输出增益光纤放大后的光信号。通过该方式，可以根据需求灵活地设计光纤放大器，如设计光器件的尾纤(即第一光纤和第二光纤)，从而可以提高光纤放大器的使用性能。例如，在需要提高第一光纤和增益光纤之间的熔接性能的情况下，可以设计第一光纤为与增益光纤基质相同或者相近的光纤，或者可以设计第一光纤为与增益光纤软化温度和/或折射率差异较小的光纤，从而可以大大降低异质光纤连接损耗。
结合第一方面，在第一方面的某些实现方式中，所述第一光纤与所述第二光纤的软化温 度的差值的绝对值大于所述第一光纤与所述增益光纤的软化温度的差值的绝对值；和/或，所述第一光纤与所述第二光纤的折射率的差值的绝对值大于所述第一光纤与所述增益光纤的折射率的差值的绝对值。
一示例，第一光纤的基质与增益光纤的基质相同或者相近。
其中，差值的绝对值用于体现差异。如第一光纤与第二光纤的软化温度的差值的绝对值大于第一光纤与增益光纤的软化温度的差值的绝对值，即表示，第一光纤与第二光纤的软化温度的差异大于第一光纤与增益光纤的软化温度的差异。又如，第一光纤与第二光纤的折射率的差值的绝对值大于第一光纤与增益光纤的折射率的差值的绝对值，即表示，第一光纤与第二光纤的折射率的差异大于第一光纤与增益光纤的折射率的差异。
基于上述技术方案，第一光纤与第二光纤的软化温度的差值的绝对值大于第一光纤与增益光纤的软化温度的差值的绝对值；和/或，第一光纤与第二光纤的折射率的差值的绝对值大于第一光纤与增益光纤的折射率的差值的绝对值。例如，光纤放大器中的光器件可以使用与增益光纤基质相同或相近的第一光纤与增益光纤相连，光器件使用与增益光纤基质不同的第二光纤与其他光器件或者输入光信号或者输出光信号相连。也就是说，与增益光纤相连的光纤的基质和增益光纤的基质相同或相近。因此，可以大大降低光纤连接处的损耗。此外，光纤连接损耗降低，有助于提升光放增益、降低噪声系数、降低加工难度、降低成本，有望成为L/S波段光放必需的技术。
结合第一方面，在第一方面的某些实现方式中，所述光器件通过所述第二光纤输入的光信号，至少通过一段自由空间到达所述第一光纤；或者，所述光器件通过所述第一光纤输入的光信号，至少通过一段自由空间到达所述第二光纤。
结合第一方面，在第一方面的某些实现方式中，所述光器件包括至少一个毛细管，所述至少一个毛细管用于将剥去涂覆层的所述第一光纤和/或所述第二光纤引入进所述光器件。
示例地，所述光器件包括至少一个光纤头，所述至少一个光纤头用于将剥去涂覆层的所述第一光纤和/或所述第二光纤引入进所述光器件。
应理解，下文中提及的毛细管均可替换为光纤头。关于毛细管和光纤头，本领域技术人员应理解其含义，光纤头为整体，毛细管为光纤头中关键部分。
还应理解，将光纤引入进光器件，或者说，将光纤装配到光器件。其并不限定光纤中光信号的传输方向，例如引入的光纤可以用于输入光信号，也可以用于输出光信号，还可以同时用于输入和输出光信号。
结合第一方面，在第一方面的某些实现方式中，所述第一光纤与所述增益光纤通过熔接方式连接。
结合第一方面，在第一方面的某些实现方式中，所述光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头。
一示例，所述WDM用于将泵浦激光器发出的泵浦光送入所述增益光纤。
又一示例，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
又一示例，所述光纤转接头用于连接所述第一光纤和所述第二光纤。
结合第一方面，在第一方面的某些实现方式中，所述光器件为WDM，所述WDM包括双线毛细管，所述双线毛细管用于引入两根光纤进所述WDM；所述两根光纤中的一根光纤 为所述第一光纤；所述两根光纤中的另一根光纤为所述第二光纤，所述两根光纤中的另一根光纤：用于连接泵浦激光器，或者用于输入光信号，或者用于输出所述增益光纤放大后的光信号。
示例地，所述WDM用于将泵浦激光器发出的泵浦光送入所述增益光纤。
结合第一方面，在第一方面的某些实现方式中，所述双线毛细管中的两根光纤不是平行的。
示例地，所述双线毛细管中的两根光纤不是平行的。
结合第一方面，在第一方面的某些实现方式中，所述WDM包括第一透镜，所述第一透镜用于：调整所述双线毛细管中的两根光纤中的光信号的光束。
结合第一方面，在第一方面的某些实现方式中，所述第一透镜对应所述第一光纤中的光信号的光路的曲面部分的曲率半径，小于所述第一透镜对应所述第二光纤中的光信号的光路的曲面部分的曲率半径；或，所述第一透镜对应所述第一光纤中的光信号的光路的径向折射率变化，快于所述第一透镜对应所述第二光纤中的光信号的光路的径向折射率变化。
结合第一方面，在第一方面的某些实现方式中，所述第一透镜支持所述双线毛细管中的两根光纤中的光信号的模斑不同。
结合第一方面，在第一方面的某些实现方式中，所述双线毛细管中的两根光纤中的光信号的模斑相匹配。
结合第一方面，在第一方面的某些实现方式中，所述光器件为隔离器，所述隔离器包括第一单线毛细管和第二单线毛细管，所述第一单线毛细管用于引入所述第一光纤进所述隔离器，所述第二单线毛细管用于引入所述第二光纤进所述隔离器。
示例地，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
结合第一方面，在第一方面的某些实现方式中，所述第一单线毛细管中的光纤和所述第二单线毛细管中的光纤不是平行的。
结合第一方面，在第一方面的某些实现方式中，所述隔离器包括第二透镜和第三透镜，所述第二透镜用于调整所述第一单线毛细管中的光纤的光信号的光束，所述第三透镜用于调整所述第二单线毛细管中的光纤的光信号的光束。
结合第一方面，在第一方面的某些实现方式中，所述第二透镜的焦距小于所述第三透镜的焦距。
结合第一方面，在第一方面的某些实现方式中，所述光器件为光纤转接头，所述光纤转接头包括第三单线毛细管和第四单线毛细管，所述第三单线毛细管用于引入所述第一光纤进所述光纤转接头，所述第四单线毛细管用于引入所述第二光纤进所述光纤转接头。
结合第一方面，在第一方面的某些实现方式中，所述第三单线毛细管中的光纤和所述第四单线毛细管中的光纤不是平行的。
结合第一方面，在第一方面的某些实现方式中，所述光纤转接头包括第四透镜和第五透镜，所述第四透镜用于调整所述第三单线毛细管中的光纤的光信号的光束，所述第五透镜用于调整所述第四单线毛细管中的光纤的光信号的光束。
结合第一方面，在第一方面的某些实现方式中，所述第四透镜的焦距小于所述第五透镜的焦距。
第二方面，提供了一种光器件。该光器件应用于光纤放大器中，该光器件，直接连接所述增益光纤，所述增益光纤用于放大光信号；所述光器件，采用第二光纤与所述光纤放大器中的一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
第一光器件直接与增益光纤连接，也即第一光器件与增益光纤连接的尾纤直接就是增益光纤，第一光器件与增益光纤之间没有熔接点。
基于上述技术方案，应用于光纤放大器中的光器件，增益光纤、与连接其他光器件(如记为第二光器件)或者输入光信号或者输出光信号(如增益光纤放大后的光信号)的光纤，折射率和/或软化温度不同。一方案中，光器件可以直接连接增益光纤，光器件可以采用第二光纤与其他光器件、输入光信号或输出增益光纤放大后的光信号连接。通过该方式，异质光纤连接损耗可以达到最小，有助于提升光放增益、降低噪声系数、降低加工难度、降低成本，有望成为L/S波段光放必需的技术。
结合第二方面，在第二方面的某些实现方式中，所述光器件通过所述第二光纤输入的光信号，至少通过一段自由空间到达所述增益光纤；或者，所述光器件通过所述增益光纤输入的光信号，至少通过一段自由空间到达所述第二光纤。
结合第二方面，在第二方面的某些实现方式中，所述光器件包括至少一个毛细管，所述至少一个毛细管用于将剥去涂覆层的所述第二光纤和/或所述增益光纤引入进所述光器件。
结合第二方面，在第二方面的某些实现方式中，所述光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头。
一示例，所述WDM用于将泵浦激光器发出的泵浦光送入所述增益光纤。
又一示例，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
又一示例，所述光纤转接头用于连接所述第二光纤和所述增益光纤。
结合第二方面，在第二方面的某些实现方式中，所述光器件为WDM，所述WDM包括双线毛细管，所述双线毛细管用于引入两根光纤进所述WDM；所述两根光纤中的一根光纤为所述增益光纤；所述两根光纤中的另一根光纤为所述第二光纤，所述两根光纤中的另一根光纤：用于连接泵浦激光器，或者用于输入光信号，或者用于输出所述增益光纤放大后的光信号。
示例地，所述WDM用于将泵浦激光器发出的泵浦光送入所述增益光纤。
结合第二方面，在第二方面的某些实现方式中，所述双线毛细管中的两根光纤不是平行的。
结合第二方面，在第二方面的某些实现方式中，所述WDM包括第一透镜，所述第一透镜用于：调整所述双线毛细管中的两根光纤中的光信号的光束。
结合第二方面，在第二方面的某些实现方式中，所述第一透镜对应所述增益光纤中的光信号的光路的曲面部分的曲率半径，小于所述第一透镜对应所述第二光纤中的光信号的光路的曲面部分的曲率半径；或，所述第一透镜对应所述增益光纤中的光信号的光路的径向折射率变化，快于所述第一透镜对应所述第二光纤中的光信号的光路的径向折射率变化。
结合第二方面，在第二方面的某些实现方式中，所述第一透镜支持所述双线毛细管中的两根光纤中的光信号的模斑不同。
结合第二方面，在第二方面的某些实现方式中，所述双线毛细管中的两根光纤中的光信号的模斑相匹配。
结合第二方面，在第二方面的某些实现方式中，所述光器件为隔离器，所述隔离器包括第一单线毛细管和第二单线毛细管，所述第一单线毛细管用于引入所述增益光纤进所述隔离器，所述第二单线毛细管用于引入所述第二光纤进所述隔离器。
示例地，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
结合第二方面，在第二方面的某些实现方式中，所述第一单线毛细管中的光纤和所述第二单线毛细管中的光纤不是平行的。
结合第二方面，在第二方面的某些实现方式中，所述隔离器包括第二透镜和第三透镜，所述第二透镜用于调整所述第一单线毛细管中的光纤的光信号的光束，所述第三透镜用于调整所述第二单线毛细管中的光纤的光信号的光束。
结合第二方面，在第二方面的某些实现方式中，所述第二透镜的焦距小于所述第三透镜的焦距。
结合第二方面，在第二方面的某些实现方式中，所述光器件为光纤转接头，所述光纤转接头包括第三单线毛细管和第四单线毛细管，所述第三单线毛细管用于引入所述增益光纤进所述光纤转接头，所述第四单线毛细管用于引入所述第二光纤进所述光纤转接头。
结合第二方面，在第二方面的某些实现方式中，所述第三单线毛细管中的光纤和所述第四单线毛细管中的光纤不是平行的。
结合第二方面，在第二方面的某些实现方式中，所述光纤转接头包括第四透镜和第五透镜，所述第四透镜用于调整所述第三单线毛细管中的光纤的光信号的光束，所述第五透镜用于调整所述第四单线毛细管中的光纤的光信号的光束。
结合第二方面，在第二方面的某些实现方式中，所述第四透镜的焦距小于所述第五透镜的焦距。
第三方面，提供了一种光纤放大器。该光纤放大器包括第一光器件、增益光纤、一个或多个第二光器件，所述增益光纤用于放大光信号；所述第一光器件，采用第一光纤与所述增益光纤连接；所述第一光器件，采用第二光纤与所述一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同。
结合第三方面，在第三方面的某些实现方式中，所述第一光器件为第一方面以及第一方面中任一可能的实现方式中所述的光器件。
第四方面，提供了一种光纤放大器。该光纤放大器包括第一光器件、增益光纤、一个或多个第二光器件，所述增益光纤用于放大光信号；所述第一光器件，直接连接所述增益光纤；所述第一光器件，采用第二光纤与所述一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
结合第四方面，在第四方面的某些实现方式中，所述第一光器件为第二方面以及第二方面中任一可能的实现方式中所述的光器件。
第五方面，提供了一种光器件制造的方法。该方法包括：采用第一光纤与增益光纤连接， 所述增益光纤用于放大光信号；采用第二光纤与一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同。
结合第五方面，在第五方面的某些实现方式中，所述第一光纤与所述第二光纤的软化温度的差值的绝对值大于所述第一光纤与所述增益光纤的软化温度的差值的绝对值。
结合第五方面，在第五方面的某些实现方式中，所述第一光纤与所述第二光纤的折射率的差值的绝对值大于所述第一光纤与所述增益光纤的折射率的差值的绝对值。
一示例，第一光纤的基质与增益光纤的基质相同或者相近。
结合第五方面，在第五方面的某些实现方式中，通过所述第二光纤输入的光信号，至少通过一段自由空间到达所述第一光纤；或者，通过所述第一光纤输入的光信号，至少通过一段自由空间到达所述第二光纤。
结合第五方面，在第五方面的某些实现方式中，所述光器件包括至少一个毛细管，通过所述至少一个毛细管将剥去涂覆层的所述第一光纤和/或所述第二光纤引入进所述光器件。
结合第五方面，在第五方面的某些实现方式中，所述第一光纤与所述增益光纤通过熔接方式连接。
结合第五方面，在第五方面的某些实现方式中，所述光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头。
一示例，所述WDM用于将泵浦激光器发出的泵浦光送入所述增益光纤。
又一示例，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
又一示例，所述光纤转接头用于连接所述第一光纤和所述第二光纤。
结合第五方面，在第五方面的某些实现方式中，所述光器件为WDM，所述WDM包括双线毛细管，通过所述双线毛细管引入两根光纤进所述WDM；所述两根光纤中的一根光纤为所述第一光纤；所述两根光纤中的另一根光纤为所述第二光纤，所述两根光纤中的另一根光纤：用于连接泵浦激光器，或者用于输入光信号，或者用于输出所述增益光纤放大后的光信号。
结合第五方面，在第五方面的某些实现方式中，所述双线毛细管中的两根光纤不是平行的。
结合第五方面，在第五方面的某些实现方式中，所述WDM包括第一透镜，通过所述第一透镜调整所述双线毛细管中的两根光纤中的光信号的光束。
结合第五方面，在第五方面的某些实现方式中，所述第一透镜对应所述第一光纤中的光信号的光路的曲面部分的曲率半径，小于所述第一透镜对应所述第二光纤中的光信号的光路的曲面部分的曲率半径；或，所述第一透镜对应所述第一光纤中的光信号的光路的径向折射率变化，快于所述第一透镜对应所述第二光纤中的光信号的光路的径向折射率变化。
结合第五方面，在第五方面的某些实现方式中，所述第一透镜支持所述双线毛细管中的两根光纤中的光信号的模斑不同。
结合第五方面，在第五方面的某些实现方式中，所述双线毛细管中的两根光纤中的光信号的模斑相匹配。
结合第五方面，在第五方面的某些实现方式中，所述光器件为隔离器，所述隔离器包括 第一单线毛细管和第二单线毛细管，通过所述第一单线毛细管引入所述第一光纤进所述隔离器，通过所述第二单线毛细管引入所述第二光纤进所述隔离器。
示例地，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
结合第五方面，在第五方面的某些实现方式中，所述第一单线毛细管中的光纤和所述第二单线毛细管中的光纤不是平行的。
结合第五方面，在第五方面的某些实现方式中，所述隔离器包括第二透镜和第三透镜，通过所述第二透镜调整所述第一单线毛细管中的光纤的光信号的光束，通过所述第三透镜调整所述第二单线毛细管中的光纤的光信号的光束。
结合第五方面，在第五方面的某些实现方式中，所述第二透镜的焦距小于所述第三透镜的焦距。
结合第五方面，在第五方面的某些实现方式中，所述光器件为光纤转接头，所述光纤转接头包括第三单线毛细管和第四单线毛细管，通过所述第三单线毛细管引入所述第一光纤进所述光纤转接头，通过所述第四单线毛细管引入所述第二光纤进所述光纤转接头。
结合第五方面，在第五方面的某些实现方式中，所述第三单线毛细管中的光纤和所述第四单线毛细管中的光纤不是平行的。
结合第五方面，在第五方面的某些实现方式中，所述光纤转接头包括第四透镜和第五透镜，通过所述第四透镜调整所述第三单线毛细管中的光纤的光信号的光束，通过所述第五透镜调整所述第四单线毛细管中的光纤的光信号的光束。
结合第五方面，在第五方面的某些实现方式中，所述第四透镜的焦距小于所述第五透镜的焦距。
第六方面，提供了一种光器件制造的方法。该方法包括：直接连接所述增益光纤，所述增益光纤用于放大光信号；采用第二光纤与光纤放大器中的一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
结合第六方面，在第六方面的某些实现方式中，通过所述第二光纤输入的光信号，至少通过一段自由空间到达所述增益光纤；或者，通过所述增益光纤输入的光信号，至少通过一段自由空间到达所述第二光纤。
结合第六方面，在第六方面的某些实现方式中，所述光器件包括至少一个毛细管，通过所述至少一个毛细管将剥去涂覆层的所述第二光纤和/或所述增益光纤引入进所述光器件。
结合第六方面，在第六方面的某些实现方式中，所述光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头。
一示例，所述WDM用于将泵浦激光器发出的泵浦光送入所述增益光纤。
又一示例，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
又一示例，所述光纤转接头用于连接所述第二光纤和所述增益光纤。
结合第六方面，在第六方面的某些实现方式中，所述光器件为WDM，所述WDM包括双线毛细管，通过所述双线毛细管引入两根光纤进所述WDM；所述两根光纤中的一根光纤为所述增益光纤；所述两根光纤中的另一根光纤为所述第二光纤，所述两根光纤中的另一根 光纤：用于连接泵浦激光器，或者用于输入光信号，或者用于输出所述增益光纤放大后的光信号。
结合第六方面，在第六方面的某些实现方式中，所述双线毛细管中的两根光纤不是平行的。
结合第六方面，在第六方面的某些实现方式中，所述WDM包括第一透镜，通过所述第一透镜调整所述双线毛细管中的两根光纤中的光信号的光束。
结合第六方面，在第六方面的某些实现方式中，所述第一透镜对应所述增益光纤中的光信号的光路的曲面部分的曲率半径，小于所述第一透镜对应所述第二光纤中的光信号的光路的曲面部分的曲率半径；或，所述第一透镜对应所述增益光纤中的光信号的光路的径向折射率变化，快于所述第一透镜对应所述第二光纤中的光信号的光路的径向折射率变化。
结合第六方面，在第六方面的某些实现方式中，所述第一透镜支持所述双线毛细管中的两根光纤中的光信号的模斑不同。
结合第六方面，在第六方面的某些实现方式中，所述双线毛细管中的两根光纤中的光信号的模斑相匹配。
结合第六方面，在第六方面的某些实现方式中，所述光器件为隔离器，所述隔离器包括第一单线毛细管和第二单线毛细管，通过所述第一单线毛细管引入所述增益光纤进所述隔离器，通过所述第二单线毛细管引入所述第二光纤进所述隔离器。
示例地，所述隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。
结合第六方面，在第六方面的某些实现方式中，所述第一单线毛细管中的光纤和所述第二单线毛细管中的光纤不是平行的。
结合第六方面，在第六方面的某些实现方式中，所述隔离器包括第二透镜和第三透镜，通过所述第二透镜调整所述第一单线毛细管中的光纤的光信号的光束，通过所述第三透镜调整所述第二单线毛细管中的光纤的光信号的光束。
结合第六方面，在第六方面的某些实现方式中，所述第二透镜的焦距小于所述第三透镜的焦距。
结合第六方面，在第六方面的某些实现方式中，所述光器件为光纤转接头，所述光纤转接头包括第三单线毛细管和第四单线毛细管，通过所述第三单线毛细管引入所述增益光纤进所述光纤转接头，通过所述第四单线毛细管引入所述第二光纤进所述光纤转接头。
结合第六方面，在第六方面的某些实现方式中，所述第三单线毛细管中的光纤和所述第四单线毛细管中的光纤不是平行的。
结合第六方面，在第六方面的某些实现方式中，所述光纤转接头包括第四透镜和第五透镜，通过所述第四透镜调整所述第三单线毛细管中的光纤的光信号的光束，通过所述第五透镜调整所述第四单线毛细管中的光纤的光信号的光束。
结合第六方面，在第六方面的某些实现方式中，所述第四透镜的焦距小于所述第五透镜的焦距。
第七方面，提供了一种光纤放大器制造的方法。该光纤放大器包括第一光器件、增益光纤、一个或多个第二光器件，所述增益光纤用于放大光信号，所述方法包括：采用第一光纤连接所述第一光器件与所述增益光纤；采用第二光纤连接所述第一光器件与所述一个或多个 第二光器件，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同。
结合第七方面，在第七方面的某些实现方式中，所述第一光器件为第一方面以及第一方面中任一可能的实现方式中所述的光器件，或者，所述第一光器件为基于第五方面以及第五方面中任一可能的实现方式中所述的方法制造的光器件。
第八方面，提供了一种光纤放大器制造的方法。该光纤放大器包括第一光器件、增益光纤、一个或多个第二光器件，所述增益光纤用于放大光信号，所述方法包括：直接连接所述第一光器件与所述增益光纤；采用第二光纤连接所述第一光器件与所述一个或多个第二光器件，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；其中，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
结合第八方面，在第八方面的某些实现方式中，所述第一光器件为第二方面以及第二方面中任一可能的实现方式中所述的光器件，或者，所述第一光器件为基于第六方面以及第六方面中任一可能的实现方式中所述的方法制造的光器件。
第九方面，提供了一种波分复用器WDM制造的方法。所述WDM应用于光纤放大器，所述WDM包括双线毛细管，所述方法包括：通过所述双线毛细管引入两根光纤进所述WDM，所述两根光纤中的一根光纤为第一光纤或增益光纤，所述两根光纤中的另一根光纤为第二光纤，所述两根光纤中的另一根光纤：用于连接泵浦激光器，或者用于输入光信号，或者用于输出所述增益光纤放大后的光信号，其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
结合第九方面，在第九方面的某些实现方式中，所述WDM为上述第一方面至第八方面中任一方面所述的WDM。
第十方面，提供了一种隔离器制造的方法。所述隔离器应用于光纤放大器，所述隔离器包括第一单线毛细管和第二单线毛细管，所述方法包括：通过所述第一单线毛细管引入第一光纤或增益光纤进所述隔离器；通过所述第二单线毛细管引入第二光纤进所述隔离器；其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
结合第十方面，在第十方面的某些实现方式中，所述隔离器为上述第一方面至第八方面中任一方面所述的隔离器。
第十一方面，提供了一种光纤转接头制造的方法。所述光纤转接头应用于光纤放大器，所述光纤转接头包括第三单线毛细管和第四单线毛细管，所述方法包括：通过所述第三单线毛细管引入第一光纤或增益光纤进所述光纤转接头；通过所述第四单线毛细管引入第二光纤进所述光纤转接头；其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
结合第十一方面，在第十一方面的某些实现方式中，所述光纤转接头为上述第一方面至第八方面中任一方面所述的光纤转接头。
第十二方面，提供了一种透镜。通过所述透镜的光路包括第一光路和第二光路；所述透镜对应所述第一光路的曲面部分的曲率半径小于所述透镜对应所述第二光路的曲面部分的曲率半径；或，所述透镜对应所述第一光路的径向折射率变化快于所述透镜对应所述第二光路的径向折射率变化。
结合第十二方面，在第十二方面的某些实现方式中，所述透镜为第一方面或第二方面以及第一方面或第二方面任一可能的实现方式中所述的第一透镜。
附图说明
图1是适用于本申请实施例的应用场景的一示意图。
图2示出了适用于本申请实施例的光纤放大器的示意性结构图。
图3示出了异质光纤折射率不同发生折射的一示意图。
图4是根据本申请实施例提供的光纤放大器的一示意图。
图5示出了适用于本申请一实施例的光纤放大器的示意图。
图6示出了适用于本申请又一实施例的光纤放大器的示意图。
图7示出了适用于本申请另一实施例的光纤放大器的示意图。
图8示出了适用于本申请再一实施例的光纤放大器的示意图。
图9示出了适用于本申请实施例的WDM的示意图。
图10示出了适用于本申请实施例的空间型WDM的膜片的示意图。
图11示出了适用于本申请实施例的调整双线毛细管中的两根光纤之间的夹角的示意图。
图12至图13示出了适用于本申请实施例的透镜的示意图。
图14示出了适用于本申请实施例的隔离器的示意图。
图15出了适用于本申请实施例的光纤转接头的示意图。
图16是根据本申请一实施例提出的光器件制造的方法的示意图。
图17是根据本申请又一实施例提出的光器件制造的方法的示意图。
图18是根据本申请一实施例提出的光纤放大器制造的方法的示意图。
图19是根据本申请又一实施例提出的光纤放大器制造的方法的示意图。
具体实施方式
下面将结合附图，对本申请中的技术方案进行描述。
本申请实施例的技术方案可以应用于光纤通信网络中，如本申请实施例的技术方案可以用于光纤通信网络中的光纤放大器中，光纤放大器主要位于光纤通信网络中的光放站点及光放网元。本申请实施例的技术方案可以用于实现由异质光纤构成的光纤放大器，也可以用于实现具有不同模斑(包括不同模斑直径，和/或，不同的数值孔径)的光纤构成的光纤放大器。下面结合图1详细说明适用于本申请实施例的场景。
图1是适用于本申请实施例的应用场景的一示意图。在光纤通信网络中，可以包括光发射机，光接收机，还可以包括一个或多个光纤放大器。如1图所示，光纤放大器在光纤通信网络中主要位于光纤线路(或者说线路光纤)中间，实现光信号的放大，延长光信号传输距离。
应理解，上述图1仅是示例性说明，本申请并未限定于此。例如，在光纤通信网络中还可以包括更多的光器件；又如，本申请实施例还可以应用于包括光纤放大器的任何场景中。
为便于理解本申请实施例，首先结合图2简单介绍光纤放大器。
如图2所示，光纤放大器例如可以包括但不限于：泵浦激光器、波分复用器(wavelength  division multiplexer，WDM)、隔离器、增益光纤。其中，泵浦激光器产生泵浦光，WDM可以将输入的光信号(或者说输入的信号光)和泵浦光合在一起送给增益光纤。增益光纤可以为其中掺杂了增益介质的光纤。在增益光纤中，泵浦光将增益光纤中增益介质离子激发到高能级，输入光信号输入后会导致增益光纤中增益介质离子从高能级跃迁到低能级时，发生受激辐射，从而放大输入的光信号，得到输出的光信号。
在光纤放大器中，增益光纤和WDM之间、增益光纤和隔离器之间一般都是采用光纤熔接的方式，这样可以降低损耗，降低噪声系数。如图2所示，WDM的尾纤与增益光纤熔接在一起，隔离器的尾纤与增益光纤熔接在一起。
在光纤通信网络中，常用的光纤放大器中的增益光纤是石英玻璃基质掺铒光纤，WDM以及隔离器等光器件的尾纤都是石英玻璃基质光纤，即两者基质相同。由于都是石英玻璃基质光纤，两者软化温度和折射率基本一致，因此WDM及隔离器的尾纤和增益光纤熔接时比较容易，熔接性能指标也比较好。例如，WDM及隔离器的尾纤和增益光纤熔接时，插损(即插入损耗(insertion loss))可以小于0.1dB(分贝，decibel，dB)，回损(即回波损耗)可以小于(-40dB)。
在一些宽谱光纤放大器中，为了提高光信号的增益，可以采用其他基质的增益光纤。例如，采用一些软玻璃光纤，如碲基掺铒光纤(在碲酸盐玻璃光纤中掺铒)、氟化物掺铥光纤(氟化物玻璃光纤中掺铥)等。这些增益光纤和石英玻璃基质光纤熔接比较困难，性能指标较差。
以增益光纤采用软玻璃光纤、WDM以及隔离器等光器件的尾纤采用石英玻璃基质光纤为例。软玻璃光纤的软化温度和石英玻璃基质光纤不同，因此，熔接时软玻璃光纤已经软化而石英玻璃基质光纤不会，软玻璃光纤熔接处变形，熔接损耗变大，一般会到1～3dB。此外，软玻璃光纤折射率一般也会与石英玻璃基质光纤不同。如石英玻璃基质光纤折射率约1.47，软玻璃光纤则可能到2.0。两种光纤平切直接熔接有较强的反射，一般需要切斜角熔接。但是切斜角熔接时，因软玻璃光纤和石英玻璃基质光纤折射率不同，会在熔接斜面上发生折射，两种光纤的模斑失配更严重，插损变大，如图3所示。同时，由于石英玻璃基质光纤没有软化而软玻璃光纤已经软化，更易造成两种光纤纤芯发生纵向移位，进一步加大熔接损耗。
有鉴于此，本申请提供一种低成本的、高性能的异质光纤构成的光纤放大器。例如，采用软化温度或折射率与石英玻璃基质光纤不同的增益光纤时，可以实现增益光纤与石英玻璃基质光纤对接从而构成光纤放大器。
下面将结合附图详细说明本申请提供的各个实施例。
图4是根据本申请实施例提出的光纤放大器的示意图。
该光纤放大器可以包括、第一光器件、一个或多个第二光器件、增益光纤。可以理解，增益光纤可以用于放大光信号。
第一光器件，与增益光纤连接，且采用第一光纤连接增益光纤或者直接连接增益光纤；
第一光器件，采用第二光纤与一个或多个第二光器件连接，和/或，采用第二光纤输入/输出光信号(即采用第二光纤输入光信号或输出增益光纤放大后的光信号)；
其中，第一光纤和第二光纤的软化温度和/或折射率不同，或者，第二光纤和增益光纤的软化温度和/或折射率不同。
在本申请实施例中，第一光器件与增益光纤连接，至少包括以下两种方案：
方案1：第一光器件采用第一光纤与增益光纤连接，如图4中的(1)所示。第一光纤和 第二光纤的软化温度和/或折射率不同。
方案2：第一光器件直接与增益光纤连接，如图4中的(2)所示。第二光纤和增益光纤的软化温度和/或折射率不同。第一光器件直接与增益光纤连接，也就是说，第一光器件连接增益光纤的尾纤为增益光纤，且第一光器件和增益光纤之间没有熔接点。
下文详细介绍该两个方案。
本申请实施例提供的由异质光纤构成的光纤放大器，以下为简洁，记为异质光纤放大器，构成该异质光纤放大器的光器件连接其他光器件的光纤和连接增益光纤的光纤不同，故灵活性较高，性能较高。在上述方案1中，该异质光纤放大器中的第一光器件使用第一光纤与增益光纤相连；该异质光纤放大器中的第一光器件使用第二光纤，与其他光器件连接或者输入光信号或者输出光信号。在上述方案2中，该异质光纤放大器中的第一光器件直接连接增益光纤，也就是说，第一光器件与增益光纤连接的尾纤就是增益光纤，第一光器件与增益光纤之间没有熔接点；该异质光纤放大器中第一光器件使用第二光纤，与其他光器件连接或者输入光信号或者输出光信号。通过该方式，可以根据需求灵活地设计并使用光纤放大器，提高光纤放大器的使用性能。例如，在上述方案1中，在需要提高第一光纤和增益光纤之间的熔接性能的情况下，可以设计第一光纤为与增益光纤基质相同或者相近的光纤，或者可以设计第一光纤为与增益光纤软化温度和/或折射率差异较小的光纤。
一个具体的示例，可以是第一光纤采用与增益光纤基质相同或相近的无源光纤，无源光纤意即其中没有掺杂增益介质的光纤，或者第一光纤直接采用增益光纤。
例如，基于上述方案1，一种可能的实现方式，第一光纤和增益光纤采用熔接的方式进行连接，也就是说第一光纤和增益光纤之间有熔接点。在实际的光纤放大器的设计中，不同批次的增益光纤的一致性会有差异，所以有时会需要调整增益光纤的长度。因此，采用第一光纤和增益光纤熔接的方式连接，可以方便地调整增益光纤的长度。同时，由于第一光纤采用与增益光纤基质相同或者相近的光纤，或者第一光纤为与增益光纤软化温度和/或折射率差异较小的光纤，第一光纤与增益光纤之间熔接的损耗、回损的性能指标较好。
又如，基于上述方案2，可以设计第一光器件直接与增益光纤连接，也即第一光器件与增益光纤连接的尾纤直接就是增益光纤，第一光器件与增益光纤之间没有熔接点。在上述方案2中，一种可能的实现方式，增益光纤直接接入或装配到第一光器件中。由于第一光器件与增益光纤之间不需要熔接，没有熔接点，因此相比上述方案1，可以进一步降低异质光纤连接的损耗，提升异质光纤放大器的性能(例如增益、噪声系数的性能等)。一般情况下，上述方案2中，第一光器件和增益光纤连成一体，不太方便调整增益光纤的长度，因此方案2比较适合在增益光纤一致性比较好的情况下实施，也就是说上述方案2对增益光纤的一致性要求比较高。
应理解，第一光纤和第二光纤仅是为区分做的命名，其命名不对本申请实施例的保护范围造成限定。
可选地，第一光纤与第二光纤的软化温度的差异大于第一光纤与增益光纤的软化温度的差异；和/或，第一光纤与第二光纤的折射率的差异大于第一光纤与增益光纤的折射率的差异。这种差异包括差值的绝对值、差值的绝对值的相对值等等。例如，第一光纤与第二光纤的软化温度的差值的绝对值大于第二光纤与增益光纤的软化温度的差值的绝对值；和/或，第一光纤与第二光纤的折射率的差值的绝对值大于第一光纤与增益光纤的折射率的差值的绝对值。 关于差异，下文不再赘述。
一示例，第一光纤的基质与增益光纤的基质相同或者接近。例如，第一光器件与增益光纤连接的光纤的软化温度，和增益光纤的软化温度相同或者接近，而第一光纤和第二光纤的软化温度的差值的绝对值大于第一光纤与增益光纤的软化温度的差值的绝对值，也即第二光纤的软化温度和第一光纤及增益光纤明显不同。
另一示例，第一光纤的折射率与增益光纤的折射率相同或者接近。例如，第一光纤与第二光纤的折射率的差值的绝对值大于第一光纤与增益光纤的折射率的差值的绝对值。在这个示例中，第一光纤、第二光纤以及增益光纤中任何两个的基质可以相同，也可以不同。
应理解，在方案1中，任何满足以下条件的第一光纤都适用于本申请实施例：第二光纤与第一光纤之间的软化温度的差异或折射率的差异，大于，第一光纤与增益光纤之间的软化温度的差异或折射率的差异。
关于第一光纤、增益光纤和第二光纤的具体形式，本申请实施例不作限定，基质不同的两类光纤，如软化温度不同的两类光纤，或者折射率不同的两种光纤，均适用于本申请实施例。
一种可能的设计，第二光纤可以是石英玻璃基质光纤，第一光纤或者增益光纤为不同于石英玻璃基质光纤的其它基质的光纤。
又一种可能的设计，第一光纤或者增益光纤可以是软玻璃光纤，如碲基掺铒光纤(在碲酸盐玻璃光纤中掺铒)、氟化物掺铥光纤(氟化物玻璃光纤中掺铥)等，或者，第一光纤或者增益光纤也可以是不同于第二光纤的其它基质的光纤，对此不作限定。
示例地，下文实施例中的第一光纤可替换为软玻璃光纤，第二光纤可替换为石英玻璃基质光纤。
第一光器件表示光纤放大器中的光器件。
可选地，第一光器件可以是WDM、隔离器、光纤转接头中的一种或多种。
一种可能的设计，第一光器件为WDM。
采用方案1，如图5所示，WDM与增益光纤相连的光纤为第一光纤，WDM与泵浦激光器以及输入光信号的光纤相连的光纤为第二光纤。第一光纤与第二光纤的软化温度的差异大于第一光纤与增益光纤的软化温度的差异；和/或，第一光纤与第二光纤的折射率的差异大于第一光纤与增益光纤的折射率的差异。一示例，第一光纤的基质和增益光纤的基质相同或接近，即WDM与增益光纤相连的光纤的基质和增益光纤的基质相同或接近。又一示例，第一光纤的玻璃结构体和增益光纤的相同或接近，即WDM与增益光纤相连的光纤的玻璃结构体和增益光纤的相同或接近。又一示例，第一光纤与增益光纤采用熔接的方式进行连接，也即第一光纤与增益光纤之间存在熔接点。
采用方案2，如图6所示，WDM直接与增益光纤连接。换句话说，增益光纤直接引入或装配到WDM中，WDM与增益光纤之间没有熔接点。WDM与泵浦激光器以及输入光信号的光纤相连的光纤为第二光纤。
又一种可能的设计，第一光器件为隔离器。
采用方案1，如图5所示，隔离器与增益光纤相连的光纤为第一光纤，隔离器与输出光信号(即通过增益光纤放大后的光信号)的光纤相连的光纤为第二光纤。第一光纤与第二光纤的软化温度的差值的绝对值大于第一光纤与增益光纤的软化温度的差值的绝对值；和/或， 第一光纤与第二光纤的折射率的差值的绝对值大于第一光纤与增益光纤的折射率的差值的绝对值。一示例，第一光纤的基质和增益光纤的基质相同或接近，即隔离器与增益光纤相连的光纤的基质和增益光纤的基质相同或接近。又一示例，第一光纤的玻璃结构体和增益光纤的相同或接近，即WDM与增益光纤相连的光纤的玻璃结构体和增益光纤的相同或接近。又一示例，第一光纤与增益光纤采用熔接的方式进行连接，也即第一光纤与增益光纤之间存在熔接点。
采用方案2，如图6所示，隔离器直接与增益光纤连接。换句话说，增益光纤直接引入到隔离器中或者增益光纤直接装配到隔离器中，隔离器和增益光纤之间没有熔接点。隔离器与输出光信号的光纤相连的光纤为第二光纤。
又一种可能的设计，第一光器件为光纤转接头。
采用方案1，如图7所示，光纤转接头(如转接头1和/或转接头2)与增益光纤相连的光纤为第一光纤，光纤转接头与隔离器或WDM相连的光纤为第二光纤。第一光纤与第二光纤的软化温度的差异大于第一光纤与增益光纤的软化温度的差异；和/或，第一光纤与第二光纤的折射率的差异大于第一光纤与增益光纤的折射率的差异。一示例，第一光纤的基质和增益光纤的基质相同或接近，即光纤转接头与增益光纤相连的光纤的基质和增益光纤的基质相同或接近。又一示例，第一光纤的玻璃结构体和增益光纤的相同或接近，即WDM与增益光纤相连的光纤的玻璃结构体和增益光纤的相同或接近。又一示例，第一光纤与增益光纤采用熔接的方式进行连接，也即第一光纤与增益光纤之间存在熔接点。
采用方案2，如图8所示，光纤转接头(如转接头1和转接头2)直接与增益光纤连接。换句话说，增益光纤直接引入到光纤转接头中，或增益光纤直接装配到光纤转接头中，光纤转接头与增益光纤之间没有熔接点。光纤转接头与隔离器、WDM相连的光纤为第二光纤。
应理解，上述图5至图8均为示例性说明，本申请实施例并未限定于此。一示例，本申请实施例对于光纤转接头的数量不作限定。例如，图7或图8中也可以包括一个光纤转接头，如仅包括转接头1或转接头2。又一示例，本申请实施例对进行改进的光器件的形式以及数量均不作限定。例如，图5中，可以仅使得WDM或隔离器与增益光纤相连的光纤为第一光纤。又如，图6中，可以仅使得WDM或隔离器与增益光纤相连的光纤为增益光纤。
下面详细介绍上述两种方案，即方案1和方案2。
方案1：第一光器件采用第一光纤与增益光纤连接。
可选地，第一光纤与增益光纤通过熔接方式连接。
第一光器件采用第一光纤与增益光纤连接，即表示第一光器件连接增益光纤的尾纤为第一光纤。一种可能的实现方式，第一光器件包括至少一个毛细管(或光纤头)，至少一个毛细管(或光纤头)用于将剥去涂覆层的第一光纤引入进或装配到第一光器件。
第一光器件采用第二光纤连接以下一项或多项：其他光器件(即一个或多个第二光器件)、输入的光信号、输出的光信号(如通过增益光纤放大后的光信号)。一种可能的实现方式，第一光器件包括至少一个毛细管，至少一个毛细管用于将剥去涂覆层的第二光纤引入进或装配到第一光器件。
应理解，第一光器件包括至少一个毛细管，至少一个毛细管用于将剥去涂覆层的第一光纤引入进第一光器件，并未限定第一光纤中光信号的传输方向，第一光纤可以用于输入光信号，也可以用于输出光信号，还可以同时用于输入和输出光信号；同样地，第一光器件包括 至少一个毛细管，至少一个毛细管用于将剥去涂覆层的第二光纤引入进第一光器件，并未限定第二光纤中光信号的传输方向，第二光纤可以用于输出光信号，也可以用于输出光信号，还可以同时用于输入和输出光信号。
还应理解，将第一光纤引入第一光器件的毛细管、与将第二光纤引入第一光器件的毛细管，可以为同一毛细管，如通过双线毛细管(或者称为双线光纤毛细管，或者称为双线光纤头)将第一光纤和第二光纤引入第一光器件；也可以为不同毛细管，如分别通过两个单线毛细管(或者称为单线光纤毛细管，或者称为单线光纤头)将第一光纤和第二光纤引入第一光器件。
第二光纤与第一光纤之间的软化温度的差异或折射率的差异，大于，第一光纤与增益光纤之间的软化温度的差异或折射率的差异。换句话说，第一光器件连接其他光器件(如记为第二光器件)的光纤，或者第一光器件输入/输出光信号的光纤，与该第一光器件连接增益光纤的光纤之间的软化温度的差异或折射率的差异，大于，该第一光器件连接增益光纤的光纤与增益光纤之间的软化温度的差异或折射率的差异。
第一光器件采用第二光纤输入的光信号，至少通过一段自由空间到达第一光纤，或者，第一光器件采用第一光纤输入的光信号，至少通过一段自由空间到达第二光纤。也就是说，第一光器件连接其他光器件或输入的光信号的光纤中传输的光信号，在该第一光器件中，至少通过一段空间到达该第一光器件连接增益光纤的光纤(即第一光纤)，或者第一光器件连接增益光纤的光纤中传输的光信号，在该光器件中，至少通过一段空间到达该第一光器件连接其他光器件或输出的光信号的光纤(即第二光纤)。
以WDM或隔离器为例。一种可能的设计方式，可以将WDM或隔离器与增益光纤相连的光纤尾纤更换成第一光纤(如与增益光纤基质相同或接近的光纤)，从而形成由异质光纤构成的光纤放大器。
示例1，如图5所示，光纤放大器可以由WDM、泵浦激光器、隔离器以及增益光纤构成。对现有的异质光纤放大器进行改进，得到改进后的异质光纤放大器。
例如，第一光纤与增益光纤的基质相同或相近。如可以将WDM和/或隔离器与增益光纤相连的光纤尾纤更换成第一光纤。WDM与泵浦激光器相连的光纤以及输入光信号的光纤、以及隔离器输出光信号(即通过增益光纤放大后的光信号)的光纤仍为第二光纤。
又如，WDM引入输入的光信号的光纤(即第二光纤)与WDM连接增益光纤的光纤(即第一光纤)，之间的软化温度或折射率差异，大于，WDM连接增益光纤的光纤与增益光纤之间的软化温度或折射率的差异。
又如，WDM连接泵浦激光器的光纤(即第二光纤)与WDM连接增益光纤的光纤，之间的软化温度或折射率差异，大于，WDM连接增益光纤的光纤与增益光纤之间的软化温度或折射率的差异。
又如，隔离器输出光信号的光纤(即第二光纤)与隔离器连接增益光纤的光纤(即第一光纤)，之间的软化温度差异，大于隔离器连接增益光纤的光纤与增益光纤之间的软化温度的差异。
图5所示的WDM，可以参考下文图9所示的WDM；和/或，图5所示的隔离器，可以参考下文图14所示的隔离器。
示例2，如图7所示，光纤放大器可以由WDM、泵浦激光器、隔离器、一个或多个光纤 转接头、以及增益光纤构成。在该示例中，可以增加一个或多个光纤转接头，如转接头1和转接头2。具体地，可以将转接头1和转接头2与增益光纤相连的光纤尾纤更换成第一光纤(如与增益光纤基质相同或接近的光纤)。转接头1与WDM相连的光纤、转接头2与隔离器相连的光纤均为第二光纤。
例如，第一光纤与增益光纤的基质相同或接近。如可以将转接头1和/或转接头2与增益光纤相连的光纤尾纤更换成第一光纤。转接头1连接WDM的光纤、以及转接头2连接隔离器的光纤仍为第二光纤。
又如，转接头1连接WDM的光纤(即第二光纤)与转接头1连接增益光纤的光纤(即第一光纤)，之间的软化温度差异，大于，转接头1连接增益光纤的光纤与增益光纤之间的软化温度差异。
又如，转接头2连接隔离器的光纤与转接头2连接增益光纤的光纤，之间的软化温度差异，大于，转接头2连接增益光纤的光纤与增益光纤之间的软化温度差异。
现有的WDM和隔离器，均可以适用于图7所示的光纤放大器中。
方案2：第一光器件直接与增益光纤连接，第一光器件与增益光纤之间没有熔接点。
第一光器件直接与增益光纤连接，即表示第一光器件连接增益光纤的尾纤直接就是增益光纤，因此第一光器件与增益光纤之间没有熔接点。一种可能的实现方式，第一光器件包括至少一个毛细管(或光纤头)，至少一个毛细管(或光纤头)用于将剥去涂覆层的增益光纤引入进或装配到第一光器件。
第一光器件采用第二光纤连接以下一项或多项：其他光器件(如记为第二光器件)、输入的光信号、输出的光信号(如通过增益光纤放大后的光信号)。一种可能的实现方式，第一光器件包括至少一个毛细管，至少一个毛细管用于将剥去涂覆层的第二光纤引入进或装配到第一光器件。
应理解，第一光器件包括至少一个毛细管，至少一个毛细管用于将剥去涂覆层的增益光纤引入进第一光器件，并未限定增益光纤中光信号的传输方向，增益光纤可以用于输入光信号，也可以用于输出光信号，还可以同时用于输入和输出光信号；同样地，第一光器件包括至少一个毛细管，至少一个毛细管用于将剥去涂覆层的第二光纤引入进第一光器件，并未限定第二光纤中光信号的传输方向，第二光纤可以用于输出光信号，也可以用于输出光信号，还可以同时用于输入和输出光信号。
还应理解，将增益光纤引入第一光器件的毛细管、与将第二光纤引入第一光器件的毛细管，可以为同一毛细管，如通过双线毛细管(或者称为双线光纤毛细管，或者称为双线光纤头)将增益光纤和第二光纤引入第一光器件；也可以为不同毛细管，如分别通过两个单线毛细管(或者称为单线光纤毛细管，或者称为单线光纤头)将增益光纤和第二光纤引入第一光器件。
该第一光器件连接其他光器件或输入/输出光信号的光纤(即第二光纤)与增益光纤的软化温度不同或折射率不同。
第一光器件采用第二光纤输入的光信号，至少通过一段自由空间到达增益光纤，或者，第一光器件采用增益光纤输入的光信号，至少通过一段自由空间到达第二光纤。也就是说，第一光器件连接其他光器件或输入/输出光信号的光纤中传输的光信号，在该第一光器件中，至少通过一段空间到达增益光纤，或者增益光纤中传输的光信号，在该第一光器件中，至少 通过一段空间到达该第一光器件连接其他光器件或输入/输出光信号的光纤(即第二光纤)。
以WDM或隔离器为例，可以将WDM或隔离器与增益光纤相连的光纤尾纤直接更换成增益光纤，从而形成由异质光纤构成的光纤放大器。
示例1，如图6所示，光纤放大器可以由WDM、泵浦激光器、隔离器以及增益光纤构成。对现有的异质光纤放大器进行改进，得到改进后的异质光纤放大器。具体地，可以将WDM以及隔离器与增益光纤相连的光纤尾纤直接更换成增益光纤。WDM与泵浦激光器相连的光纤、WDM输入光信号的光纤、以及隔离器输出光信号的光纤均为第二光纤。
如上所述，第一光器件直接连接增益光纤，该第一光器件连接其他光器件或输入/输出光信号的光纤与增益光纤的软化温度不同或折射率不同。
例如，WDM和/或隔离器直接连接增益光纤。
又如，WDM引入输入光信号的光纤(即第二光纤)与增益光纤的软化温度或折射率不同。
又如，WDM连接泵浦激光器的光纤(即第二光纤)与增益光纤的软化温度或折射率不同。
又如，隔离器输出光信号的光纤(即第二光纤)与增益光纤的软化温度或折射率不同。
图6所示的WDM，可以参考下文图9所示的WDM；和/或，图6所示的隔离器，可以参考下文图14所示的隔离器。
示例2，如图8所示，光纤放大器可以由WDM、泵浦激光器、隔离器、一个或多个光纤转接头、以及增益光纤构成。在该示例中，可以增加一个或多个光纤转接头，如转接头1和转接头2。具体地，可以将转接头1和转接头2与增益光纤相连的光纤尾纤直接更换成增益光纤。转接头1与WDM相连的光纤、转接头2与隔离器相连的光纤均为第二光纤。
如上所述，第一光器件直接连接增益光纤，该第一光器件连接其他光模块或输入/输出光信号的光纤与增益光纤的软化温度不同或折射率不同。
例如，转接头1或转接头2可以直接连接增益光纤。
又如，转接头1连接WDM的光纤(即第二光纤)与增益光纤的软化温度不同。
又如，转接头2连接隔离器的光纤(即第二光纤)与增益光纤的软化温度不同。
现有的WDM和隔离器，均可以适用于图8所示的光纤放大器中。
应理解，上述结合图5至图8示例地介绍了方案1和方案2，本申请实施例并未限定于此。一示例，方案1和方案2还可以结合使用。例如，如图5至图8中，部分光器件使用方案1，部分光器件使用方案2。如图5或图6中，WDM与增益光纤相连的光纤为第一光纤，隔离器直接连接增益光纤(或者增益光纤直接引入进或装配到隔离器中)。
还应理解，上述方案1和方案2仅是示例性说明，本申请实施例并未限定于此。例如，第一光纤也可以是与增益光纤软化温度或折射率接近的光纤。
通过本申请实施例提供的异质光纤放大器，与增益光纤相连的光纤的基质和增益光纤的基质相同或接近。因此，本申请实施例提供的异质光纤放大器，可以大大降低异质光纤连接损耗。异质光纤连接是实现L波段光放、S波段光放等的普遍要求。由于光传输频谱效率(spectrum effectiveness，SE)接近香农极限。因此，为了进一步提升光纤传输容量，一个重要的方向就是扩展可用频谱，从C波段往L波段以及S波段扩展。为了达到和C波段光放近似的增益，L及S波段光放的增益光纤一般要采用有别于石英玻璃基质的其他基质光纤。但 是线路上的光纤是石英玻璃基质光纤，现有的光放模块中的WDM、隔离器等光器件的尾纤也是石英玻璃基质光纤，因此L\S光放就需要实现异质光纤连接。
(1)如上文所述，本申请实施例中异质光纤连接处的损耗和现有光放(即光纤放大器)中石英玻璃基质光纤熔接的损耗相当。本申请实施例提供的异质光纤放大器，异质光纤连接处的损耗与同质光纤构成的光纤放大器中光纤连接处的损耗相当，如与现有光纤放大器中石英玻璃基质光纤熔接的损耗相当。石英玻璃基质光纤熔接损耗在0.1dB左右，如果异质光纤直接熔接，损耗将达到0.5dB～1dB，本申请实施例提供的异质光纤放大器理论上损耗也能达到与0.1dB相近的值。特别是，如果第一光器件直接连接增益光纤，熔接损耗甚至低于石英玻璃基质光纤熔接损耗。
(2)异质光纤连接损耗降低后，光放增益就能实现相应幅度的提升。假设一个光放有四个连接点，则光放增益大致能提升1.6～3.6dB。L/S波段光放的主要问题之一是增益偏小，因此如果增益能提升这个幅度，对L/S波段光放很重要。
(3)异质光纤连接损耗降低后，能降低光放的噪声系数。特别是第一段增益光纤之前的连接损耗对光放噪声系数影响较大。例如，本申请实施例提供的异质光纤放大器，相对现有的异质光纤熔接的方案来说，光放噪声系数能降低0.4～0.9dB。L/S波段的另一个主要的问题就是噪声系数偏高，因此本申请实施例提供的异质光纤放大器对实现实用的L/S波段光放很重要。
(3)由于不同基质光纤软化温度不同，因此异质光纤熔接比较困难，失败概率大，成本高。基于本申请实施例，可以进行同质光纤熔接，因此加工难度低、成本低。
因此，本申请实施例提供的异质光纤构成的光放模块(其中包括至少一个第一光器件)，异质光纤连接损耗可以达到最小，有助于提升光放增益、降低噪声系数、降低加工难度、降低成本，有望成为L/S波段光放必需的技术。
上文介绍了本申请实施例提供的光纤放大器，下文介绍可以构成光纤放大器的各个光器件。应理解，下文所述的各个光器件可以单独使用，或者，也可以结合使用，或者，也可以用于图4至图8所述的光纤放大器中。
结合图9介绍适用于本申请实施例的WDM。该WDM可以为图4实施例中所述的第一光器件。图9所示的WDM，可以用于图4至图8所述的光纤放大器中。
图9示出了适用于本申请实施例的WDM的一示意图。该WDM中可以包括一个或多个透镜，如透镜1和透镜2。该WDM中还可以包括WDM膜片、单线毛细管(如单线毛细管1)、双线毛细管(如双线毛细管1)。
单线毛细管，例如也可以称为单线光纤毛细管，本领域技术人员应理解其含义，例如也可以替换为单线光纤头。双线毛细管，例如也可以称为双线光纤毛细管，本领域技术人员应理解其含义，例如也可以替换为双线光纤头。下文为统一，均用单线毛细管和双线毛细管表示。
可选地，本申请实施例可以采用空间光路的WDM。通过该方式，可以规避不同基质的光纤玻璃软化温度带来的熔接的问题。或者，也可以使用其他类型的WDM，对此，不作限定。
WDM模块可以用于完成信号光以及泵浦光合路或合波的功能。如图9所示，信号光经过第二光纤送到WDM膜片，泵浦光经过第二光纤也送到WDM膜片。WDM膜片可以完成 信号光和泵浦光的合路或合波，形成混合光。应理解，混合光仅是为区分做的命名，混合光也可以称为合波光，其命名不对本申请实施例的保护范围造成限定。下文统一用混合光表示。
以图9为例，一可能的流程如下所述。
(1)单线毛细管1从第二光纤(即信号光输入光纤)输入光信号，送到透镜1。可以理解，输入光信号中的光信号为泛指的光信号，即表示光信号被引进或者被引入或者被输入，也就是说，第二光纤输入的光信号就是信号光。
一种可能的实现方式，可以将第二光纤剥去涂覆层，插入毛细管中，再磨成斜面并镀膜。
(2)透镜1主要是对单线毛细管1送来的光信号的光束(在这里也就是信号光的光束)进行准直。
单线毛细管1将信号光送到空间中，在空间中，信号光会发散。因此，经过透镜1进行准直后，就可以将信号光变成平行光或近似平行光。
(3)WDM膜片主要是实现透镜1送来的信号光与透镜2送来的泵浦光的合波或合路。
一种可能的实现方式，如图10所示。在基底上镀上多层膜，透镜2送来的泵浦光通过多层膜入射，透镜1送来的信号光通过基底入射，合波后的产生的混合光通过多层膜发射到透镜2。
应理解，上述流程仅是示例性说明，本申请实施例并未限定于此。实际上，也可以是泵浦光经过单线毛细管1送入，信号光经过双线毛细管1送入。另外，图5和图6中的WDM为用于提供前向泵浦的WDM，实际上WDM也可用于提供后向泵浦，本申请实施例并未限定于此。WDM用于提供后向泵浦时，WDM的结构与提供前向泵浦的WDM类似(见图9)，信号光是输出，泵浦光是输入，而混合光则既有输入也有输出。不管是对于前向泵浦WDM还是后向泵浦WDM，其工作原理是类似的，因此两者的实施方案也是类似，不再赘述。
在本申请实施例中，WDM中混合光输出光纤为第一光纤(方案1)或增益光纤(方案2)，信号光输入光纤以及泵浦光输入光纤为第二光纤。
关于第一光纤和第二光纤，参考上文描述，下面不再赘述。
可选地，可以通过以下任一方式，调整或准直混合光和泵浦光的光束。
方式1，调整双线毛细管中的两根光纤之间的夹角，使得双线毛细管中的两根光纤不平行，以便准直泵浦光的光束以及混合光的光束。
结合图9可知，图9中的WDM为支持前向泵浦的WDM，双线毛细管1的主要功能包括：从泵浦光输入光纤(即第二光纤)引入泵浦光，送到透镜2，并且接收从透镜2送来的混合光，送入混合光输出光纤(第一光纤或增益光纤)。或者从信号光输入光纤(即第二光纤)引入信号光，送到透镜2，并且接收从透镜2送来的混合光，送入混合光输出光纤。如果WDM为支持后向泵浦的WDM，双线毛细管1的主要功能包括：从泵浦光输入光纤(即第二光纤)引入泵浦光，送到透镜2，并且从透镜2到混合光输出光纤(第一光纤或增益光纤)的混合光中有部分是从透镜2送到混合光输出光纤，也有部分是从混合光输出光纤送到透镜2的，此时“混合光输出光纤”仅仅是个名称，并不代表光纤中的光信号传输方向；或者从信号光输入光纤(即第二光纤)引入信号光，送到透镜2，并且从透镜2到混合光输出光纤(第一光纤或增益光纤)的混合光中有部分是从透镜2送到混合光输出光纤，也有部分是从混合光输出光纤送到透镜2的，此时“混合光输出光纤”仅仅是个名称，并不代表光纤中的光信号传输方向。
一示例，可以根据第一光纤或增益光纤的折射率设计双线毛细管(即双线毛细管1)中的两根光纤之间的夹角，以便准直混合光的光束。
例如，可以根据折射原理及混合光输出光纤(第一光纤或增益光纤)的折射率，调整混合光输出光纤(第一光纤或增益光纤)与泵浦光输入光纤/信号光输入光纤(第二光纤)的夹角，使得混合光光束对准WDM膜片的相应位置。
如图11所示，在双线毛细管1中的第一光纤/增益光纤与第二光纤的夹角Δθ＝θ4-θ3，假设第一光纤/增益光纤的折射率为n1，第二光纤的折射率为n2。一般情况下，两路光束在透镜中是平行的，即两路光束经过自由空间到透镜的折射角θ1相同。假设透镜中各部分折射率相同，则两路光束在透镜2到自由空间的折射角及自由空间到双线毛细管的折射角θ2相同，则根据折射定律有sinθ2＝n1*sinθ3＝n2*sinθ4。设计时，θ2可以根据WDM膜片最佳入射角/出射角度、WDM膜片、透镜及双线毛细管的结构及光学参数等设定，这样就可以根据上式计算出在双线毛细管1中的第一光纤/增益光纤与第二光纤的夹角。
方式2，通过透镜调整双线毛细管中的两根光纤中光信号的光束，例如通过透镜调整双线毛细管中的两根光纤输入或输出的光信号的光斑或模斑，以便准直泵浦光的光束以及混合光的光束，和/或对齐双线毛细管中的两根光纤中光信号在WDM膜片上的光斑或模斑(包括光斑或模斑的大小，和/或光斑或模斑的发散角等)。
透镜主要可以实现空间光路的准直，同时也可以调整光束的光斑或模斑，例如，实现具有不同直径、和/或不同发散角的光束准直到具有相同或相近的光斑或模斑大小的平行(或近似平行)光束上。在本申请实施例中，透镜(即图9中的透镜2)可以为支持双光路的透镜。
一种可能的设计，可以采用非球面的C透镜，如图12所示。
该C透镜(即图9中的透镜2)上半部分的曲率半径小，下半部分的曲率半径大。换句话说，该C透镜对应混合光光路(也即对应第一光纤或增益光纤)的曲率半径小于该C透镜对应泵浦光光路(也即对应第二光纤)的曲率半径。相比于现有支持双光路的球面的C透镜来说，本申请实施例提供的C透镜更加灵活，应用场景较多。
应理解，在该C透镜中，曲率半径的大小是相对而言的，即上部分的曲率半径相对于下部分的曲率半径而言比较小。上下部分的曲率半径的取值，不作限定。
还应理解，在该C透镜中，曲率半径小的曲面所占的部分，和曲率半径大的曲面所占的部分，不作限定。只要对应混合光光路的曲率半径小于对应泵浦光光路的曲率半径，均适用于本申请实施例。
又一种可能的设计，可以采用非对称的G透镜，如图13所示。
该G透镜(即图9中的透镜2)上半部分沿径向的折射率变化快于，下半部分沿径向的折射率变化。换句话说，该G透镜对应混合光光路(也即对应第一光纤或增益光纤的光路)沿径向的折射率变化快于，该G透镜对应泵浦光光路(也即对应第二光纤的光路)沿径向的折射率变化。相比于现有的支持双光路的G透镜来说，本申请实施例提供的G透镜更加灵活，应用场景较多。
应理解，在该G透镜中，折射率沿径向变化的快慢是相对而言的，即上部分沿径向的折射率变化相对于下部分沿径向的折射率变化而言比较快。上下部分的折射率沿径向变化的取值，不作限定。
还应理解，只要对应混合光光路的折射率沿径向变化快于对应泵浦光光路的折射率沿径 向变化，均适用于本申请实施例。
上述两种设计仅为示例性说明，本申请实施例并未限定于此。
基于上述方式2，可以采用透镜，如非球面的C透镜或非对称的G透镜，实现让不同基质光纤的光束都对准，和/或对齐不同基质光纤的光束、在选定的位置处(例如WDM膜片表面)的光斑或模斑(包括光斑或模斑的大小，和/或光斑或模斑的发散角等)，即准直第一光纤或增益光纤中的光信号的光束(如混合光的光束)与第二光纤中的光信号的光束(如泵浦光的光束)，和/或调整第一光纤或增益光纤中的光信号的光束与第二光纤中的光信号的光束的模斑或光斑。
应理解，上述方式1和方式2仅为示例性说明，任何可以准直光信号的光束(如准直混合光和泵浦光的光束)，和/或任何可以调整光束的模斑/光斑的方案，都可以用于本申请实施例。
在本申请实施例中，光信号光斑或模斑(包括光斑或模斑的大小，和/或发散角)可能相同，也可能不同，下面主要介绍光信号模斑不同的情况。
可选地，混合光输出光纤(第一光纤或增益光纤)的模斑可能会小于泵浦光输入光纤(第二光纤)的模斑，即Φ3<Φ1；和/或，混合光输出光纤的模斑可能会小于信号光输入光纤(第二光纤)的模斑，即Φ3<Φ2。WDM膜片接收泵浦光的模斑与WDM膜片输出混合光的模斑应该相同或相近，即Φ4≈Φ5。
一可能的情况，本申请实施例中的双线毛细管1，对应混合光光路的光纤模斑小于对应泵浦光光路的，即Φ3<Φ2。
示例1，透镜(即透镜2)支持混合光光路的模斑与泵浦光光路的模斑不同。
例如，可以根据混合光光路的模斑以及泵浦光光路的模斑，设计透镜。如可以设计透镜的曲率半径或折射率分布，以调整其焦距。该透镜可以为图12或图13所示的透镜。
基于上述示例1，可以采用透镜，如非球面的C透镜或非对称的G透镜，支持混合光光路的光纤模斑与对应泵浦光光路的光纤模斑不同。
示例2，设计双线毛细管(即双线毛细管1)，以支持混合光光路的模斑与泵浦光光路的模斑不同。
例如，可以根据混合光光路的模斑以及泵浦光光路的模斑，设计双线毛细管。如可以设计双线毛细管的位置，以对准透镜的焦点。双向毛细管1可以将混合光输出光纤(第一光纤或增益光纤)以及泵浦光输入光纤(第二光纤)剥去涂覆层，插入毛细管中，再磨成斜面并镀膜。
示例3，调整泵浦光输入光纤(第二光纤)。例如，选择和混合光输出光纤(第一光纤或增益光纤)模斑匹配的石英玻璃基质光纤作为泵浦光输入光纤。
基于本申请实施例，采用本申请实施例提供的WDM，可以改变光纤放大器中的WDM与增益光纤的连接方式。在光纤放大器中，WDM与增益光纤的对接，可以变成同质光纤(或者接近于同质光纤)的对接(即方案1，如第一光纤为与增益光纤基质相同或接近的光纤，或者，第一光纤与增益光纤的折射率接近和/或软化温度接近)，或者完全无需对接(即方案2，WDM直接连接增益光纤)，这样就可以避免异质光纤熔接带来的问题。
上文结合图9至图13介绍了适用于本申请实施例的WDM。下文结合图14介绍适用于本申请实施例的隔离器。该隔离器可以为图4实施例中所述的第一光器件。图14所示的隔离 器，可以用于图4至图8所述的光纤放大器中。图14所示的隔离器，可以与图9所示的WDM分别单独使用，也可以结合使用。
图14示出了适用于本申请实施例的隔离器的一示意图。该隔离器中可以包括一个或多个透镜，如透镜3和透镜4。该隔离器中还可以包括光隔离器中心器件、至少一个单线毛细管(如单线毛细管2和单线毛细管3)。示例地，该光隔离中心器件中例如可以包括：楔形双折射晶体(如楔形双折射晶体1和楔形双折射晶2)、法拉第旋转器。
隔离器用于让沿一个方向传输的光信号通过或让沿一个方向传输的光信号损耗较小，而让沿反方向传输的光信号不能通过或损耗较大。隔离器可以用于抑制输出光纤之后(例如图14中的放大信号光输出光纤)可能的反射光的传输。放大的信号光经过放大信号光输入光纤(第一光纤或增益光纤)送到光隔离器中心件，然后送到放大信号光输出光纤(第二光纤)。放大信号光输出光纤之后可能的反射光经过放大信号光输出光纤可以送到光隔离器中心件，但是经过光隔离器中心件后并不能送到放大信号光输入光纤，从而抑制了可能的反射光的反向传输。
以图14为例，一可能的流程如下所述。
(1)单线毛细管2从第一光纤或增益光纤(即放大信号光输入光纤)引入放大后的信号光，送到透镜3。
一种可能的实现方式，可以将第一光纤或增益光纤剥去涂覆层，插入毛细管中，再磨成斜面并镀膜。透镜3主要是对单线毛细管2送来的信号光进行准直。单线毛细管2将信号光送到空间中，在空间中，信号光会发散。因此，经过透镜3进行准直后，就可以将信号光变成平行光或近似平行光。
(2)光隔离器中心件作为光隔离器的核心，可以用于实现光信号的单向传输。
一种可能的实现方式，光隔离器中心件将从透镜3接收的放大后的信号光，送到透镜4，同时将透镜4送来的下段可能的反射光，偏离单线毛细管2到透镜3的光路的方向，送给透镜3。由于偏离了方向，所以透镜3接收到下段可能的反射光后并不能将其耦合进放大信号光输入光纤。一示例，光隔离器中心件可以由2片楔形的双折射晶体、磁铁以及钇铁石榴石制成的法拉第旋转器构成。
(3)透镜4接收到光隔离器中心件送来的放大后的信号光后，送到单线毛细管3，最终经过放大信号光输出光纤(即第二光纤)输出。该部分功能和实现方式和放大信号光输入光纤、单线毛细管2以及透镜3类似，只是方向相反。此处不再赘述。
应理解，上述流程仅是示例性说明，本申请实施例并未限定于此。
在本申请实施例中，放大信号光输入光纤为第一光纤(方案1)或增益光纤(方案2)，放大信号光输出光纤为第二光纤。
关于第一光纤和第二光纤，参考上文描述，下面不再赘述。
可选地，可以通过以下任一方式，调整或准直放大后的信号光的光束。
方式1，调整单线毛细管2和单线毛细管3中的光纤之间的夹角，使得单线毛细管2和单线毛细管3中的光纤不平行，以便准直放大后的信号光的光束。
一示例，可以通过第一光纤或增益光纤的折射率以及第二光纤的折射率调整单线毛细管2和单线毛细管3中的光纤之间的夹角，以便准直或调整放大后的信号光的光束。
例如，可以根据折射原理以及放大信号光输入光纤的折射率，调整放大信号光输入光纤 在单线毛细管2中的位置，以便准直放大后的信号光的光束，如使得放大后的信号光的光束对准光隔离器中心件的相应位置。
具体的可以参考图9所示实施例中方式1的描述，此处不再赘述。
方式2，通过透镜调整单线毛细管中光纤的光信号的光束，例如通过透镜调整单线毛细管中的光纤的光信号的光斑或模斑，以便准直放大后的信号光的光束，和/或对齐单线毛细管2中的光纤的光信号和单线毛细管3中的光纤的光信号在隔离器中间件上的光斑或模斑(包括光斑或模斑的大小，和/或光斑或模斑的发散角等)。
如图14所示，隔离器中的透镜3用于准直和/或调整单线毛细管2中的光纤的光信号的光束(第一光纤或增益光纤的光信号的光束)，隔离器中的透镜4用于准直和/或调整单线毛细管3中的光纤的光信号的光束(第二光纤的光信号的光束)。
可选地，透镜3的焦距小于透镜4的焦距。
应理解，上述方式1和方式2仅为示例性说明，任何可以准直和/或调整光信号的光束(如准直和/或调整放大后的信号光的光束)的方案，都可以用于本申请实施例。
在本申请实施例中，光信号光斑或模斑(包括光斑或模斑的大小，和/或发散角)可能相同，也可能不同，下面主要介绍光信号模斑不同的情况。
可选地，放大信号光输入光纤(第一光纤或增益光纤)的模斑可能会小于放大信号光输出光纤(第二光纤)的模斑，即Φ6<Φ7。光隔离器中心件接收放大后的信号光的模斑Φ8与光隔离器中心件发送放大后的信号光的模斑Φ9相关，而Φ9又与Φ7相关。
示例1，透镜(如透镜3)支持放大信号光输出光纤的模斑与放大信号光输入光纤的模斑不同。
例如，可以根据放大信号光输出光纤以及放大信号光输入光纤的模斑，设计透镜3。如可以设计透镜3的曲率半径或折射率分布。
基于上述示例1，可以采用透镜，支持放大信号光输出光纤以及放大信号光输入光纤的模斑不同。
示例2，设计单线毛细管(如单线毛细管2和单线毛细管3)，以支持放大信号光输出光纤的模斑与放大信号光输入光纤的模斑不同。
例如，可以根据放大信号光输出光纤以及放大信号光输入光纤的模斑，设计单线毛细管2及单线毛细管3，以对准光隔离器中心件的相应位置。如可以设计单线毛细管2及单线毛细管3的位置。
示例3，调整放大信号光输出光纤(第二光纤)。例如，选择和放大信号光输入光纤(第一光纤或增益光纤)模斑匹配的石英玻璃基质光纤作为放大信号光输出光纤。
基于本申请实施例，采用本申请实施例提供的隔离器，可以改变光纤放大器中的隔离器与增益光纤的连接方式。在光纤放大器中，隔离器与增益光纤的对接，可以变成同质光纤(或者接近于同质光纤)的对接(即方案1，如第一光纤为与增益光纤基质相同或接近的光纤，或者，第一光纤与增益光纤的折射率接近和/或软化温度接近)，或者完全无需对接(即方案2，隔离器直接连接增益光纤)，这样就可以避免异质光纤熔接带来的问题。
上文结合图9至图13介绍了适用于本申请实施例的WDM，结合图14介绍了适用于本申请实施例的隔离器，下文结合图15介绍适用于本申请实施例的光纤转接头。该光纤转接头可以为图4实施例中所述的第一光器件。图15所示的光纤转接头，可以用于图4至图8所述 的光纤放大器中。图15所示的光纤转接头，可以与图9所示的WDM、图14所示的隔离器，分别单独使用，也可以结合使用。
图15示出了适用于本申请实施例的光纤转接头的一示意图。该光纤转接头中可以包括一个或多个透镜，如透镜5和透镜6。该光纤转接头中还可以包括至少一个单线毛细管，如单线毛细管4和单线毛细管5。该光纤转接头例如也可以记为异质光纤转接头或转接头。该光纤转接头可以为图7或图8中所示的转接头1，也可以为图7或图8中所示的转接头2。
光纤转接头用于连接第一光纤和第二光纤，或者，光纤转接头用于连接第二光纤和所述增益光纤。光纤转接头可以用于实现具有不同折射率或软化温度的光纤空间耦合，从而降低光纤连接的损耗。
由于光路可逆，因此，图15中光信号可以从光纤1输入、光纤2输出；或者，图15中光信号也可以从光纤2输入、光纤1输出。光纤1为第一光纤或增益光纤，光纤2为第二光纤；或者，光纤2为第一光纤或增益光纤，光纤1为第二光纤。
例如，图15所示的光纤转接头为图7中的转接头1的情况下，光纤1可以为第二光纤，光纤2可以为第一光纤。
又如，图15所示的光纤转接头为图7中的转接头2的情况下，光纤1可以为第一光纤，光纤2可以为第二光纤。
又如，图15所示的光纤转接头为图8中的转接头1的情况下，光纤1可以为第二光纤，光纤2可以为增益光纤。
又如，图15所示的光纤转接头为图8中的转接头2的情况下，光纤1可以为增益光纤，光纤2可以为第二光纤。
以光信号从光纤1输入、光纤1的模斑小于光纤2的为例，一可能的流程，光信号从光纤1输入，单线毛细管4从光纤1引入光信号，送到透镜5。透镜5对光信号进行准直，送给透镜6。透镜6将光信号耦合进单线毛细管5和光纤2。
可选地，调整单线毛细管4和单线毛细管5中的光纤之间的夹角，使得单线毛细管4和单线毛细管5中的光纤不平行，以便准直光信号的光束(放大后的信号光的光束)。
可选地，通过透镜调整单线毛细管中光纤的光信号的光束，例如通过透镜调整单线毛细管中的光纤的光信号的光斑或模斑，以便准直光信号的光束(放大后的信号光的光束)，和/或对齐单线毛细管4中的光纤的光信号和单线毛细管5中的光纤的光信号在透镜5与透镜6之间的光斑或模斑(包括光斑或模斑的大小，和/或光斑或模斑的发散角等)。
可选地，用于引入第一光纤或增益光纤进光纤转接头的透镜的焦距小于用于引入第二光纤进光纤转接头的透镜的焦距。
可选地，透镜(如透镜5或透镜6)支持光纤1的模斑与光纤2的模斑不同。
可选地，设计单线毛细管(如单线毛细管4或单线毛细管5)，以支持光纤1的模斑与光纤2的模斑不同。
关于单线毛细管4可以参考图14所示的单线毛细管2、单线毛细管5可以参考图14所示的单线毛细管3，透镜5可以参考图14所示的透镜3、透镜6可以参考图14所示的透镜4，此处不再赘述。或者，关于单线毛细管5可以参考图14所示的单线毛细管2、单线毛细管4可以参考图14所示的单线毛细管3，透镜6可以参考图14所示的透镜3、透镜5可以参考图14所示的透镜4，此处不再赘述。
基于本申请实施例，采用本申请实施例提供的光纤转接头，可以改变光纤放大器中的各个光模块与增益光纤的连接方式。在光纤放大器中，光纤转接头与增益光纤的对接，可以变成同质光纤(或者接近于同质光纤)的对接(即方案1，如第一光纤为与增益光纤基质相同或接近的光纤，或者，第一光纤与增益光纤的折射率接近和/或软化温度接近)，或者完全无需对接(即方案2，光纤转接头直接连接增益光纤)。光纤转接头与WDM或隔离器的对接，可以变成同质光纤(或者接近于同质光纤)的对接(如光纤转接头与WDM或隔离器相连的光纤的基质与第二光纤的基质相同)，或者完全无需对接(即光纤转接头与WDM或隔离器相连的光纤为第二光纤)，这样就可以避免异质光纤熔接带来的问题。
在上述一些实施例中，以WDM、隔离器、光纤转接头为例进行了示例性说明，对此不作限定。只要光器件连接不同光模块(或者说光器件)的光纤不完全相同，都适用于本申请实施例。一示例，光器件直接连接增益光纤，连接其他光器件或者输入/输出光信号的光纤为不同于增益光纤的光纤。又一示例，光器件采用第一光纤连接增益光纤，采用不同于第一光纤的光纤连接其他光器件或者输入/输出光信号。
上文结合图4至图15介绍了适用于本申请实施例的装置实施例(如光器件、光纤放大器)，下面结合图16至图19，详细描述本申请的方法实施例。装置侧的描述和方法测的描述相互对应，为了简洁，适当省略重复的描述。
图16是本申请一实施例提供的光器件制造的方法的示意性流程图。基于图16的方法1600获得的光器件可以为前文提及的第一光器件(方案1中的第一光器件)，或者，也可以用于前文提及的光纤放大器(方案1中的光纤放大器)中。方法1600可以包括如下步骤。
1610，采用第一光纤与增益光纤连接，该增益光纤用于放大光信号；
1620，采用第二光纤与一个或多个第二光器件连接，和/或，采用第二光纤输入光信号或输出增益光纤放大后的光信号，其中，第一光纤和第二光纤的软化温度和/或折射率不同。
一示例，第一光纤与第二光纤的软化温度的差异(或差值的绝对值)大于第一光纤与增益光纤的软化温度的差异(或差值的绝对值)。
又一示例，第一光纤与第二光纤的折射率的差异(或差值的绝对值)大于第一光纤与增益光纤的折射率的差异(或差值的绝对值)。
又一示例，第一光纤的基质与增益光纤的基质相同。
又一示例，通过第二光纤输入的光信号，至少通过一段自由空间到达第一光纤；或者，通过第一光纤输入的光信号，至少通过一段自由空间到达第二光纤。
又一示例，通过至少一个毛细管将剥去涂覆层的第一光纤和/或第二光纤引入进或装配到光器件。
又一示例，第一光纤与增益光纤通过熔接方式连接。
又一示例，光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头。
又一示例，光器件为WDM，WDM包括双线毛细管，通过双线毛细管引入两根光纤进WDM；两根光纤中的一根光纤为第一光纤；两根光纤中的另一根光纤为第二光纤，两根光纤中的另一根光纤用于：连接泵浦激光器，或者用于输入光信号，或者用于输出增益光纤放大后的光信号。
又一示例，双线毛细管中的两根光纤不是平行的。
又一示例，WDM包括第一透镜，通过第一透镜调整双线毛细管中的两根光纤中的光信 号的光束。
又一示例，第一透镜对应第一光纤中的光信号的光路的曲面部分的曲率半径，小于第一透镜对应第二光纤中的光信号的光路的曲面部分的曲率半径；或，第一透镜对应第一光纤中的光信号的光路的径向折射率变化，快于第一透镜对应第二光纤中的光信号的光路的径向折射率变化。
又一示例，第一透镜支持双线毛细管中的两根光纤中的光信号的模斑不同。
又一示例，双线毛细管中的两根光纤中的光信号的模斑相匹配。
又一示例，光器件为隔离器，隔离器包括第一单线毛细管和第二单线毛细管，通过第一单线毛细管引入第一光纤进隔离器，通过第二单线毛细管引入第二光纤进隔离器。
又一示例，第一单线毛细管中的光纤和第二单线毛细管中的光纤不是平行的。
又一示例，隔离器包括第二透镜和第三透镜，通过第二透镜调整第一单线毛细管中的光纤的光信号的光束，通过第三透镜调整第二单线毛细管中的光纤的光信号的光束。
又一示例，第二透镜的焦距小于所述第三透镜的焦距。
又一示例，光器件为光纤转接头，光纤转接头包括第三单线毛细管和第四单线毛细管，通过第三单线毛细管引入第一光纤进光纤转接头，通过第四单线毛细管引入第二光纤进所光纤转接头。
又一示例，第三单线毛细管中的光纤和第四单线毛细管中的光纤不是平行的。
又一示例，光纤转接头包括第四透镜和第五透镜，通过第四透镜调整第三单线毛细管中的光纤的光信号的光束，通过第五透镜调整第四单线毛细管中的光纤的光信号的光束。
又一示例，第四透镜的焦距小于第五透镜的焦距。
图17是本申请又一实施例提供的光器件制造的方法的示意性流程图。基于图17的方法1700获得的光器件可以为前文提及的第一光器件(方案2中的第一光器件)，或者，也可以用于前文提及的光纤放大器(方案2中的光纤放大器)中。方法1700可以包括如下步骤。
1710，直接连接增益光纤，增益光纤用于放大光信号；
1720，采用第二光纤与一个或多个第二光器件连接，和/或，采用第二光纤输入光信号或输出增益光纤放大后的光信号，其中，第二光纤和增益光纤的软化温度和/或折射率不同。
一示例，通过第二光纤输入的光信号，至少通过一段自由空间到达增益光纤；或者，通过增益光纤输入的光信号，至少通过一段自由空间到达第二光纤。
又一示例，通过至少一个毛细管将剥去涂覆层的增益光纤和/或第二光纤引入进或装配到光器件。
又一示例，光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头。
又一示例，光器件为WDM，WDM包括双线毛细管，通过双线毛细管引入两根光纤进WDM；两根光纤中的一根光纤为增益光纤；两根光纤中的另一根光纤为第二光纤，两根光纤中的另一根光纤：用于连接泵浦激光器，或者用于输入光信号，或者用于输出增益光纤放大后的光信号。
又一示例，双线毛细管中的两根光纤不是平行的。
又一示例，WDM包括第一透镜，通过第一透镜调整双线毛细管中的两根光纤中的光信号的光束。
又一示例，第一透镜对应增益光纤中的光信号的光路的曲面部分的曲率半径，小于第一 透镜对应第二光纤中的光信号的光路的曲面部分的曲率半径；或，第一透镜对应增益光纤中的光信号的光路的径向折射率变化，快于第一透镜对应第二光纤中的光信号的光路的径向折射率变化。
又一示例，第一透镜支持双线毛细管中的两根光纤中的光信号的模斑不同。
又一示例，双线毛细管中的两根光纤中的光信号的模斑相匹配。
又一示例，光器件为隔离器，隔离器包括第一单线毛细管和第二单线毛细管，通过第一单线毛细管引入增益光纤进隔离器，通过第二单线毛细管引入第二光纤进隔离器。
又一示例，第一单线毛细管中的光纤和第二单线毛细管中的光纤不是平行的。
又一示例，隔离器包括第二透镜和第三透镜，通过第二透镜调整第一单线毛细管中的光纤的光信号的光束，通过第三透镜调整第二单线毛细管中的光纤的光信号的光束。
又一示例，第二透镜的焦距小于所述第三透镜的焦距。
又一示例，光器件为光纤转接头，光纤转接头包括第三单线毛细管和第四单线毛细管，通过第三单线毛细管引入增益光纤进光纤转接头，通过第四单线毛细管引入第二光纤进所光纤转接头。
又一示例，第三单线毛细管中的光纤和第四单线毛细管中的光纤不是平行的。
又一示例，光纤转接头包括第四透镜和第五透镜，通过第四透镜调整第三单线毛细管中的光纤的光信号的光束，通过第五透镜调整第四单线毛细管中的光纤的光信号的光束。
又一示例，第四透镜的焦距小于第五透镜的焦距。
图18是本申请一实施例提供的光纤放大器制造的方法的示意性流程图。基于图18的方法1800获得的光纤放大器可以为前文提及的光纤放大器(方案1中的光纤放大器)中。方法1800可以包括如下步骤。
1810，采用第一光纤连接第一光器件与增益光纤，该增益光纤用于放大光信号；
1820，采用第二光纤连接第一光器件与一个或多个第二光器件，和/或，采用第二光纤输入光信号或输出增益光纤放大后的光信号，其中，第一光纤和第二光纤的软化温度和/或折射率不同。
第一光器件为上文提及的第一光器件，此处不再赘述。
图19是本申请又一实施例提供的光纤放大器制造的方法的示意性流程图。基于图19的方法1900获得的光纤放大器可以为前文提及的光纤放大器(方案2中的光纤放大器)中。方法1900可以包括如下步骤。
1910，直接连接第一光器件与增益光纤，增益光纤用于放大光信号；
1920，采用第二光纤连接第一光器件与一个或多个第二光器件，和/或，采用第二光纤输入光信号或输出增益光纤放大后的光信号，其中，第二光纤和增益光纤的软化温度和/或折射率不同。
第一光器件为上文提及的第一光器件，此处不再赘述。
本领域普通技术人员可以意识到，结合本文中所公开的实施例描述的各示例的步骤，能够以电子硬件、或者计算机软件和电子硬件的结合来实现。这些功能究竟以硬件还是软件方式执行，取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用使用不同方法来实现所描述的功能，但是这种实现不应认为超出本申请的保护范围。
所属领域的技术人员可以清楚地了解到，为描述方便和简洁，上述描述的方法的具体工 作过程，可以参考前述装置实施例中的对应过程，在此不再赘述
在上述实施例中，可以全部或部分地通过软件、硬件、固件或者其任意组合来实现。
当使用软件实现时，可以全部或部分地以计算机程序产品的形式实现。该计算机程序产品包括一个或多个计算机指令。在计算机上加载和执行计算机程序指令时，全部或部分地产生按照本申请实施例所述的流程或功能。计算机可以是通用计算机、专用计算机、计算机网络、或者其他可编程装置。例如，计算机可以是个人计算机，服务器，或者网络设备等。计算机指令可以存储在计算机可读存储介质中，或者从一个计算机可读存储介质向另一个计算机可读存储介质传输，例如，计算机指令可以从一个网站站点、计算机、服务器或数据中心通过有线(例如同轴电缆、光纤、数字用户线(DSL))或无线(例如红外、无线、微波等)方式向另一个网站站点、计算机、服务器或数据中心进行传输。关于计算机可读存储介质，可以参考上文描述。
以上所述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到的变化或替换，都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以权利要求和说明书的保护范围为准。

Claims (24)

  1. 一种光器件，其特征在于，应用于光纤放大器中，
    所述光器件，采用第一光纤与增益光纤连接，或者，所述光器件直接连接所述增益光纤，其中，所述增益光纤用于放大光信号；
    所述光器件，采用第二光纤与所述光纤放大器中的一个或多个第二光器件连接，或者，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；
    其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
  2. 根据权利要求1所述的光器件，其特征在于，
    所述第一光纤与所述第二光纤的软化温度的差值的绝对值大于所述第一光纤与所述增益光纤的软化温度的差值的绝对值；和/或，
    所述第一光纤与所述第二光纤的折射率的差值的绝对值大于所述第一光纤与所述增益光纤的折射率的差值的绝对值。
  3. 根据权利要求1或2所述的光器件，其特征在于，
    所述光器件通过所述第二光纤输入的光信号，至少通过一段自由空间到达所述第一光纤或所述增益光纤；或者，
    所述光器件通过所述第一光纤或所述增益光纤输入的光信号，至少通过一段自由空间到达所述第二光纤。
  4. 根据权利要求1至3中任一项所述的光器件，其特征在于，所述光器件包括至少一个毛细管，所述至少一个毛细管用于将剥去涂覆层的以下一项或多项引入进所述光器件：所述第一光纤、所述第二光纤、所述增益光纤。
  5. 根据权利要求1至4中任一项所述的光器件，其特征在于，
    所述第一光纤与所述增益光纤通过熔接方式连接。
  6. 根据权利要求1至5中任一项所述的光器件，其特征在于，
    所述光器件为以下任一项或多项：波分复用器WDM、隔离器、光纤转接头，
    其中，所述光纤转接头用于连接所述第一光纤和所述第二光纤，或者，所述光纤转接头用于连接所述第二光纤和所述增益光纤。
  7. 根据权利要求6所述的光器件，其特征在于，所述光器件为WDM，
    所述WDM包括双线毛细管，所述双线毛细管用于引入两根光纤进所述WDM；
    所述两根光纤中的一根光纤为所述第一光纤或所述增益光纤；
    所述两根光纤中的另一根光纤为所述第二光纤，所述两根光纤中的另一根光纤用于：连接泵浦激光器，或者用于输入光信号，或者用于输出所述增益光纤放大后的光信号。
  8. 根据权利要求7所述的光器件，其特征在于，
    所述双线毛细管中的两根光纤不是平行的。
  9. 根据权利要求7或8所述的光器件，其特征在于，
    所述WDM包括第一透镜，所述第一透镜用于调整所述双线毛细管中的两根光纤中的光信号的光束。
  10. 根据权利要求9所述的光器件，其特征在于，
    所述第一透镜对应所述第一光纤或所述增益光纤中的光信号的光路的曲面部分的曲率半径，小于所述第一透镜对应所述第二光纤中的光信号的光路的曲面部分的曲率半径；或，
    所述第一透镜对应所述第一光纤或所述增益光纤中的光信号的光路的径向折射率变化，快于所述第一透镜对应所述第二光纤中的光信号的光路的径向折射率变化。
  11. 根据权利要求6所述的光器件，其特征在于，所述光器件为隔离器，
    所述隔离器包括第一单线毛细管和第二单线毛细管，
    所述第一单线毛细管用于引入所述第一光纤或所述增益光纤进所述隔离器，所述第二单线毛细管用于引入所述第二光纤进所述隔离器。
  12. 根据权利要求11所述的光器件，其特征在于，
    所述第一单线毛细管中的光纤和所述第二单线毛细管中的光纤不是平行的。
  13. 根据权利要求11或12所述的光器件，其特征在于，
    所述隔离器包括第二透镜和第三透镜，
    所述第二透镜用于调整所述第一单线毛细管中的光纤的光信号的光束，所述第三透镜用于调整所述第二单线毛细管中的光纤的光信号的光束。
  14. 根据权利要求13所述的光器件，其特征在于，
    所述第二透镜的焦距小于所述第三透镜的焦距。
  15. 根据权利要求6所述的光器件，其特征在于，所述光器件为光纤转接头，
    所述光纤转接头包括第三单线毛细管和第四单线毛细管，
    所述第三单线毛细管用于引入所述第一光纤或所述增益光纤进所述光纤转接头，所述第四单线毛细管用于引入所述第二光纤进所述光纤转接头。
  16. 根据权利要求15所述的光器件，其特征在于，
    所述第三单线毛细管中的光纤和所述第四单线毛细管中的光纤不是平行的。
  17. 根据权利要求15或16所述的光器件，其特征在于，
    所述光纤转接头包括第四透镜和第五透镜，
    所述第四透镜用于调整所述第三单线毛细管中的光纤的光信号的光束，所述第五透镜用于调整所述第四单线毛细管中的光纤的光信号的光束。
  18. 根据权利要求17所述的光器件，其特征在于，
    所述第四透镜的焦距小于所述第五透镜的焦距。
  19. 一种光纤放大器，其特征在于，包括第一光器件、增益光纤、一个或多个第二光器件，所述增益光纤用于放大光信号；
    所述第一光器件，采用第一光纤与所述增益光纤连接，或者，
    所述第一光器件，直接连接所述增益光纤；
    所述第一光器件，采用第二光纤与所述一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；
    其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
  20. 根据权利要求19所述的光纤放大器，其特征在于，所述第一光器件为权1至权18 中任一项或多项所述的光器件。
  21. 一种光器件制造的方法，其特征在于，包括：
    采用第一光纤与增益光纤连接，或者，直接连接所述增益光纤，其中，所述增益光纤用于放大光信号；
    采用第二光纤与一个或多个第二光器件连接，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；
    其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
  22. 根据权利要求21所述的方法，其特征在于，所述光器件为权1至权18中任一项或多项所述的光器件。
  23. 一种光纤放大器制造的方法，其特征在于，包括第一光器件、增益光纤、一个或多个第二光器件，所述增益光纤用于放大光信号，所述方法包括：
    采用第一光纤连接所述第一光器件与所述增益光纤，或者，直接连接所述第一光器件与所述增益光纤；
    采用第二光纤连接所述第一光器件与所述一个或多个第二光器件，和/或，采用所述第二光纤输入光信号或输出所述增益光纤放大后的光信号；
    其中，所述第一光纤和所述第二光纤的软化温度和/或折射率不同，或者，所述第二光纤和所述增益光纤的软化温度和/或折射率不同。
  24. 根据权利要求23所述的方法，其特征在于，所述第一光器件为权1至权18中任一项或多项所述的光器件，或者，所述第一光器件为基于如权21或权22所述的方法制造的光器件。
PCT/CN2021/094865 2020-06-04 2021-05-20 构成光纤放大器的光器件、光纤放大器以及制造方法 WO2021244298A1 (zh)

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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5283846A (en) * 1991-06-21 1994-02-01 Hitachi, Ltd. Optical isolator, optical circuit, and rare-earth-doped fiber optical amplifier
CN1094818A (zh) * 1993-01-07 1994-11-09 康宁股份有限公司 光纤耦合器及放大器
US5473713A (en) * 1993-07-26 1995-12-05 France Telecom Etablissement Autonome De Droit Public Optical amplifier having a doped fluoride glass optical fibre and process for producing this amplifier
US5513033A (en) * 1992-06-27 1996-04-30 Northern Telecom Limited Optical fibre amplifier
CN101211087A (zh) * 2006-12-31 2008-07-02 华为技术有限公司 一种光纤放大器及制作方法及光纤通信系统
CN108390245A (zh) * 2018-04-28 2018-08-10 无锡市德科立光电子技术有限公司 超小型光纤放大器
CN110829166A (zh) * 2019-12-10 2020-02-21 中国人民解放军国防科技大学 一种具有光束净化功能的拉曼光纤放大器

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5283846A (en) * 1991-06-21 1994-02-01 Hitachi, Ltd. Optical isolator, optical circuit, and rare-earth-doped fiber optical amplifier
US5513033A (en) * 1992-06-27 1996-04-30 Northern Telecom Limited Optical fibre amplifier
CN1094818A (zh) * 1993-01-07 1994-11-09 康宁股份有限公司 光纤耦合器及放大器
US5473713A (en) * 1993-07-26 1995-12-05 France Telecom Etablissement Autonome De Droit Public Optical amplifier having a doped fluoride glass optical fibre and process for producing this amplifier
CN101211087A (zh) * 2006-12-31 2008-07-02 华为技术有限公司 一种光纤放大器及制作方法及光纤通信系统
CN108390245A (zh) * 2018-04-28 2018-08-10 无锡市德科立光电子技术有限公司 超小型光纤放大器
CN110829166A (zh) * 2019-12-10 2020-02-21 中国人民解放军国防科技大学 一种具有光束净化功能的拉曼光纤放大器

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