CN110579886A - Method and system for branching polarized light and polarization-maintaining transmission - Google Patents
Method and system for branching polarized light and polarization-maintaining transmission Download PDFInfo
- Publication number
- CN110579886A CN110579886A CN201810581644.2A CN201810581644A CN110579886A CN 110579886 A CN110579886 A CN 110579886A CN 201810581644 A CN201810581644 A CN 201810581644A CN 110579886 A CN110579886 A CN 110579886A
- Authority
- CN
- China
- Prior art keywords
- light
- splitting
- laser
- optical fiber
- module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
- G02B27/283—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising used for beam splitting or combining
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
- G02B27/286—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Optical Couplings Of Light Guides (AREA)
Abstract
the invention discloses a method and a system for branching polarized light and transmitting the polarized light in a polarization-preserving way, wherein the method comprises the following steps: a depolarization step, setting a depolarization module to change laser into completely unpolarized light; a light splitting step, namely setting a light splitting module, splitting laser or completely unpolarized light into multiple paths of light, and enabling the laser or completely unpolarized light to enter an optical fiber splitter through an optical fiber coupler and to be emitted from an optical fiber collimator; and a polarizing step, setting a polarizing module, and converting the completely unpolarized light of each path into linearly polarized light for the required equipment. The laser polarization splitting device has the advantages that laser is split firstly, backed off and then polarized or reversed firstly and then polarized, the laser is divided into multiple paths of laser with required quantity, the power of each path of laser is approximately equal and is polarized light, the light splitting module comprises an optical fiber splitter, the whole light splitting process is more stable, the system volume is reduced, and the system complexity is reduced.
Description
Technical Field
The invention relates to the technical field of polarized light transmission, in particular to a method and a system for branching polarized light and transmitting the polarized light in a polarization-preserving way.
Background
The high-power laser is expensive, when multiple paths of laser are needed for work or experiments, the cost of multiple high-power lasers cannot be borne generally, and the existing light splitting method, such as a light splitter or an optical beam splitter, which adopts the beam splitter has the defect that a complex splitting system needs to be built, so that energy loss is caused in the transmission process, each lens needs to be accurately adjusted, and the system is easily influenced by vibration, so that the light path is deviated; and an optical fiber splitter is adopted for splitting, but because laser is a coherent light source with better polarization, the polarization of the laser split by the optical fiber splitter is poor, and for some working or experimental places needing laser to keep polarization characteristics, the laser split by the optical fiber splitter can not meet the requirements.
Disclosure of Invention
In order to overcome the defects of the prior art, an object of the present invention is to provide a method and a system for splitting polarized light and polarization-preserving transmission, which divide laser into multiple paths, keep the power of each path of laser approximately equal, and are all polarized light, and can obtain multiple paths of laser without a plurality of lasers, thereby greatly reducing the cost.
in order to achieve the above object, the present invention provides a method for splitting polarized light and transmitting the polarized light with polarization maintaining, comprising the following steps:
a depolarization step, setting a depolarization module to change laser into completely unpolarized light;
a light splitting step, namely setting a light splitting module, splitting laser or completely unpolarized light into multiple paths of light, and enabling the laser or completely unpolarized light to enter an optical fiber splitter through an optical fiber coupler and to be emitted from an optical fiber collimator;
And a polarizing step, setting a polarizing module, and converting the completely unpolarized light of each path into linearly polarized light for the required equipment.
One way of implementing the step of depolarization is that the depolarization module is a depolarization device,
preferably, the depolarizer is arranged in front of the light splitting module, and the laser is converted into completely unpolarized light after passing through the depolarizer and then divided into multiple paths of light by the light splitting module;
preferably, the depolarizer is disposed behind the fiber collimator, and after the laser is split into multiple paths of light by the splitting module, each path of light is processed by the depolarizer to become completely unpolarized light.
The other realization mode of the depolarization step is that the depolarization module is a large-core-diameter multimode fiber with a certain length, and is connected with a fiber splitter in the light splitting module, and the laser enters the fiber splitter and then is divided into multiple paths of light which respectively enter the corresponding large-core-diameter multimode fibers and become completely unpolarized light.
one implementation manner of the light splitting step is that the light splitting module comprises a plurality of stages of optical fiber splitters, laser or completely unpolarized light enters the first stage of optical fiber splitters through the optical fiber coupler, and the split light enters the plurality of optical fiber splitters in the next stage until the required path number of light is obtained.
Preferably, the optical splitting module further includes an optical splitting device, the optical splitting device is disposed in front of the multiple stages of optical fiber splitters, laser or completely unpolarized light is primarily split by the optical splitting device, the primarily split light enters the first stage of optical fiber splitters through the optical fiber coupler, and then enters the next stage of optical fiber splitters respectively until the required path number of light is obtained.
In another aspect of the present invention, the present invention further provides a system for splitting and polarization maintaining transmission of polarized light, comprising:
a laser;
At least one fiber coupler;
the light splitting module is used for splitting laser into multiple paths and comprises an optical fiber splitter, wherein the optical fiber coupler is arranged in front of the optical fiber splitter;
The optical fiber collimator is arranged behind the optical fiber branching unit and connected with the optical fiber branching unit;
The depolarization module is used for changing the laser light into completely unpolarized light; and
and the polarizing module is arranged behind the depolarization module and used for converting the laser light which becomes completely unpolarized light into polarized light.
Preferably, the polarization-reversing module is a polarization-reversing device and is arranged before the optical fiber splitter or after the optical fiber collimator.
the other structure of the depolarization module is that the depolarization module is a large-core-diameter multimode optical fiber with a certain length, is connected with the optical fiber splitter and is arranged between the optical fiber splitter and the optical fiber collimator.
One structure of the optical splitting module is that the optical splitting module comprises a plurality of stages of optical fiber splitters, and the optical fiber coupler is connected with the first stage of optical fiber splitters.
Preferably, the optical splitting module comprises an optical splitting device, and the optical fiber coupler is arranged between the optical splitting device and the multistage optical fiber splitter.
Compared with the prior art, the invention has the beneficial effects that:
According to the method, the laser is subjected to light splitting, back-off and polarization treatment and then polarization treatment or light splitting and then polarization treatment after back-off, the laser is divided into the required number of paths of lasers, the power of each path of laser is approximately equal and is polarized light, and the light splitting module comprises the optical fiber splitter, so that the whole light splitting process is more stable, the system volume is reduced, and the system complexity is reduced.
Drawings
FIG. 1 is a schematic flow chart of an implementation method of an embodiment of the present invention, which shows a processing flow of depolarization before polarization;
FIG. 2 is a flow chart illustrating a process of polarization after beam splitting and back polarization according to another embodiment of the present invention;
FIG. 3 is a schematic diagram of a frame structure according to an embodiment of the present invention, which shows a frame structure employing a depolarizer that depolarizes light before splitting light;
FIG. 4 is a schematic diagram of a frame structure according to another embodiment of the present invention, which shows a frame structure employing a depolarizer for splitting light, depolarizing light, and polarizing light;
FIG. 5 is a schematic diagram of a frame structure of another embodiment of the present invention, showing a split-back-polarizing-before-polarizing frame structure using a large core multimode fiber;
FIG. 6 is a schematic flow chart showing a process of first split-optical back-off-polarization and then polarization using a large-core multimode fiber according to another embodiment of the present invention;
fig. 7 is a schematic structural diagram of a light splitting module according to an embodiment of the present invention;
fig. 8 is a schematic structural diagram of a light splitting module according to another embodiment of the present invention;
FIG. 9 is a schematic structural diagram of an optical splitting device according to the present invention;
In the figure: 10. a depolarization module; 11. a depolarizer; 12. a large core diameter multimode optical fiber; 13. completely unpolarized light; 20. a light splitting module; 21. an optical fiber splitter; 22. an optical splitting device; 30. a polarizing module; 40. an optical fiber; 41. a fiber coupler; 42. a fiber collimator; 50. laser; 51. a laser.
Detailed Description
the present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.
the following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be in a particular orientation, constructed and operated in a particular orientation, and thus the above terms are not to be construed as limiting the present invention.
It is understood that the terms "a" and "an" should be interpreted as meaning that a number of one element or element is one in one embodiment, while a number of other elements is one in another embodiment, and the terms "a" and "an" should not be interpreted as limiting the number.
In the present invention, unless otherwise expressly specified or limited, the terms "assembled", "connected", and "connected" are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; or may be a mechanical connection; the two elements can be directly connected or connected through an intermediate medium, and the two elements can be communicated with each other. The specific meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.
As shown in fig. 1 to 9, the method and system for splitting polarized light and polarization maintaining transmission according to the embodiment of the present invention will be clarified in the following description, and the method and system thereof solve the problem of splitting laser into a required number of multiple paths of laser light, ensure that the power of each path of laser light is approximately equal, and the laser light is polarized light, and multiple paths of laser light can be obtained without a plurality of lasers, so that the cost is greatly reduced, and the whole light splitting process is more stable, the system volume is reduced, and the system complexity is reduced by using an optical fiber splitter.
The optical splitter 21 is included in the optical splitting module 20 of this embodiment, and compared with a conventional spectroscope or an optical splitter, the optical splitting system is simpler, and meanwhile, based on the optical splitter, the optical fiber 40 is adopted for connection between the optical splitter and the optical collimator in this embodiment, which is beneficial to reducing the volume of equipment and the complexity of the system. The types of the optical fibers generally include single-mode optical fibers and multi-mode optical fibers, the single-mode optical fibers also include polarization-maintaining single-mode optical fibers and non-polarization-maintaining single-mode optical fibers, and in some systems with requirements on laser polarization characteristics, the polarization-maintaining single-mode optical fibers can be adopted, the stability of the optical fibers is good, and the polarization characteristics of laser can be well maintained in the laser transmission process, but the optical fibers have the defects that the light transmission efficiency of the optical fibers is weak, laser energy loss is easily caused, the use difficulty is high, and the price is high; some systems also adopt multimode fibers, have high light transmission efficiency and simpler use, but have lower stability than polarization-maintaining single-mode fibers, and are easy to disturb the polarization of laser.
therefore, the method and the system of the embodiment simplify the polarization light splitting structure, ensure that the polarization characteristic of the laser is still maintained after the laser is transmitted, greatly reduce the cost, and are beneficial to commercial popularization of a plurality of working or experimental systems which need multiple paths of laser and have requirements on the polarization characteristic of the laser.
as shown in fig. 1 and fig. 2, a method for splitting polarized light and transmitting the polarized light in a polarization maintaining manner includes the following steps:
A depolarization step of setting a depolarization module 10 to change the laser light 50 into completely unpolarized light 13;
a light splitting step, in which a light splitting module 20 is arranged to split the laser 50 or the completely unpolarized light 13 into multiple paths of light, and the laser 50 or the completely unpolarized light 13 is incident into the optical fiber splitter 21 through the optical fiber coupler 41 and is emitted from the optical fiber collimator 42;
And a polarizing module 30 is arranged to convert the completely unpolarized light 13 of each path into linearly polarized light for the required equipment.
Since the laser passing through the optical fiber splitter is partially polarized light and the polarization direction thereof is not fixed, the laser cannot be directly converted into linearly polarized light by the polarization module 30, which is easy to greatly lose laser power and make the laser unusable. Therefore, the method of the invention firstly changes the laser 50 into the completely unpolarized light 13 by performing the processes of light splitting, back-polarizing and then polarizing or the processes of light splitting, back-polarizing and then polarizing on the laser 50, then changes the completely unpolarized light 13 into the linearly polarized light by using the polarizing module 30, reduces the power loss for the subsequent system to use, divides the laser into the required number of paths of light before or after changing the laser into the completely unpolarized light 13, and then changes the light into the polarized light before using, so that the power of each path of laser used is approximately equal and is the polarized light. Regardless of whether the splitting is performed first or the depolarization is performed first, the laser light may be converted into the completely unpolarized light 13 and polarized light before the end of the transmission. The polarizing module 30 in this embodiment may adopt a polarization beam splitter, the completely unpolarized light 13 is split into a horizontally polarized light and a vertically polarized light by the polarization beam splitter, and the powers of the two beams are completely the same. The laser 51 in the present invention refers to a device capable of emitting laser light in a broad sense, and the whole process starts with the laser light generated by the laser 51, not with the emission from the laser emitting device. In reality, the output interfaces of some laser emitting devices are optical fibers and are built in the optical fiber coupler 41, and when the processes of depolarization before beam splitting and then polarization are performed in the application process, the output interfaces of the laser emitting devices need to be connected with the optical fiber collimator 42 to lead out laser, and after depolarization by the depolarization module 10, the laser is led into the optical fiber splitter 21 through the other optical fiber coupler 41 to perform beam splitting; when the processes of splitting, backing, and then starting the polarization are performed, the output interface of the laser emitting device is directly connected with the optical fiber splitter 21 to split the light, and the optical fiber coupler 41 described in the present invention is the optical fiber coupler 41 built in the laser emitting device.
One way of implementing the depolarization step is that, in the depolarization step, the depolarization module 10 is a depolarization unit 11,
as shown in fig. 3, the depolarizer 11 is disposed in front of the light splitting module 20, the laser light 50 passes through the depolarizer 11 and then becomes the completely unpolarized light 13, and then is split into multiple paths of light by the light splitting module 20, and the light splitting process is performed after the depolarization;
alternatively, as shown in fig. 4, the depolarizer 11 is disposed behind the fiber collimator 42, the laser light 50 is split into multiple beams by the splitting module 20, and each beam is processed by the depolarizer 11 to become completely unpolarized light 13, and is split first and depolarized later.
It should be noted that, since the optical splitter 21 is included in the optical splitting module 20, and the depolarizer 11 and the polarizer are both optical components, the optical fiber coupler 41 and the optical fiber collimator 42 need to be disposed, and the laser light emitted by the laser 51 also enters the optical splitter 21 through the optical fiber coupler 41.
More specifically, as shown in fig. 3, in an embodiment of separating light after depolarization and polarizing again, laser light emitted from a laser 51 first undergoes polarization disturbance through a depolarizer 11 to become completely unpolarized light 13, the completely unpolarized light 13 enters an optical fiber splitter 21 through an optical fiber coupler 41 to be split into multiple paths of light, each path of laser light is transmitted to an optical fiber collimator 42 through an optical fiber, the optical fiber collimator 42 is connected with a polarizing module 30, the emitted laser light is changed into linearly polarized light again, the polarizing module 30 is a polarizing beam splitter, the completely unpolarized light 13 is split into horizontally polarized light and vertically polarized light through the polarizing beam splitter, and the powers of the two beams of light are completely the same.
In another embodiment of splitting, back-polarizing and polarization-re-polarizing, laser enters the fiber splitter 21 through the fiber coupler 41, and is split into multiple beams of laser, then each beam of laser is transmitted to the fiber collimator 42, the fiber collimator 42 is connected with the polarization splitter 11, the laser emitted from the fiber collimator 42 is changed into completely unpolarized light 13, the polarization module 30 after the polarization splitter 11 changes the completely unpolarized light 13 into linearly polarized light, the polarization module 30 is a polarization beam splitter, the completely unpolarized light 13 is split into horizontally polarized light and vertically polarized light by the polarization beam splitter, and the power of the two beams of light is completely the same.
As the core diameter of the optical fiber is thicker, the modes transmitted inside the optical fiber are more, the coupling efficiency of the laser is higher, but the polarization of the laser is more disordered, so that the polarization of the laser can be disturbed by using the large-core-diameter multimode optical fiber 12 with a certain length, the laser transmitted in the large-core-diameter multimode optical fiber 12 with a sufficient length can be finally changed into completely unpolarized light 13, and therefore, another implementation manner of the depolarization step is that, as shown in fig. 5 and 6, in the depolarization step, the depolarization module 10 is the large-core-diameter multimode optical fiber 12 with a certain length and is connected with the optical splitter 21 in the light splitting module 20, the laser is divided into multiple paths of light after entering the optical splitter 21 and respectively enters the corresponding large-core-diameter multimode optical fibers 12, and is changed into completely unpolarized light 13 in the transmission process, and the depolarization processing is performed first.
More specifically, as shown in fig. 5 and 6, the laser enters the fiber splitter 21 through the fiber coupler 41, is divided into a plurality of laser beams, and then each laser beam enters the corresponding large-core-diameter multimode fiber 12, and is converted into completely unpolarized light 13 during transmission, and then is output through the fiber collimator 42, and is converted into polarized light through the polarization module 30, the polarization module 30 is a polarization beam splitter, and the completely unpolarized light 13 is divided into horizontally polarized light and vertically polarized light through the polarization beam splitter, and the power of the two light beams is completely the same. Experiments show that the large-core-diameter multimode optical fiber 12 has a core diameter of 400-800 micrometers and a length of more than meter level. The core diameter of the multimode fiber in the optical fiber branching unit 21 is 50 microns or 62.5 microns, the laser coupling efficiency from the multimode fiber with the thin core diameter to the multimode fiber with the thick core diameter is high, the optical fiber branching unit 21 and the multimode fiber 12 with the large core diameter are connected through a switching flange plate, and the optical fiber collimator 42 is connected with the multimode fiber 12 with the large core diameter.
The splitting step of the present invention is realized in such a way that the splitting module 20 includes a plurality of stages of optical fiber splitters 21, the laser or completely unpolarized light 13 enters the first stage of optical fiber splitters 21 through the optical fiber coupler 41, and the split light enters the next stage of optical fiber splitters 21 until the required path number of light is obtained. The optical fiber splitter 21 is a commonly used splitter in the field of communications equipment at present, and is used for splitting one laser into n paths, where n generally has specifications such as 2/4/8/16/32/64, and certainly has special values other than the above values, and from the types of optical fibers, there are a single-mode optical fiber splitter and a multi-mode optical fiber splitter, where the single-mode optical fiber has a relatively small core diameter (generally less than 10 microns), the difficulty of coupling the laser into the optical fiber is high, and the cost of the coupler is high; meanwhile, the power transmitted by the single-mode optical fiber is much lower than that of the multimode optical fiber. The invention adopts the multimode fiber splitter, thereby reducing the system cost. One optical splitter 21 itself can be used as the splitting module 20, and when the number of required laser beams is relatively large and a single optical splitter 21 cannot meet the requirement, a multi-stage optical splitter 21 can be adopted to connect the input interface of the next stage optical splitter 21 to the output of the previous stage optical splitter 21, thereby exponentially increasing the number of output paths. However, the optical fiber splitters 21 have a large number of stages, which may cause adverse effects such as optical power loss and splitting non-uniformity, and many laser application systems, for example, an atomic magnetic force sensor, require that the power deviation of each laser is not more than 10%. It will be understood by those skilled in the art that the number and specification of the optical splitters 21 are not limited in the embodiment of the present invention, and may be set according to the number of laser beams required in practical applications, for example, in the specific example shown in fig. 7, the content and features of the light splitting method according to the embodiment of the present invention are illustrated and disclosed by taking the example of splitting 8 lights by using the two-stage 2-way optical splitter 21, but splitting 8 lights by using the two-stage 2-way optical splitter 21 is not to be considered as limiting the content and scope of the light splitting method according to the preferred embodiment. Alternatively, in other possible examples of the light splitting method of the present embodiment, the adopted optical splitter 21 may also be, but not limited to, 4/8/16/32/64, or the like, or may also be a special value other than the above value, and due to the optimization of the optical splitter 21 itself, the number of stages may also be 3, 4, 5, or the like, so that the power deviation of each path may meet the requirements of the laser application system.
Because the number of stages of the optical fiber splitters is multiple, which may cause optical power loss, uneven splitting, and other adverse results, preferably, as shown in fig. 8, the optical splitting module 20 further includes an optical splitting device 22, the optical splitting device 22 is disposed in front of the multi-stage optical fiber splitter 21, laser or completely unpolarized light 13 is primarily split by the optical splitting device 22, the primarily split light enters the first stage of optical fiber splitter 21 through the optical fiber coupler 41, and then enters the next stage of optical fiber splitters 21 respectively until the required number of paths of light is obtained. The laser beam emitted from the laser 51 is divided into n paths by the optical splitting device 22, the optical splitting device 22 adopts optical devices such as a lens, a prism, a reflector and the like to divide the laser input into a plurality of laser beams to be output, the laser beams emitted and incident at this time are both space free light, the optical fiber coupler 41 is arranged behind the optical splitting device 22, and the laser beams divided by the optical splitting device 22 are connected into the optical fiber splitter 21 at the next stage by the optical fiber coupler 41 to be further split. In practical applications, for some laser emitting devices with optical fibers as output interfaces, the optical fiber collimator 42 is required to be applied to lead out laser, and then the optical splitting device 22 is used to split the laser, and the existing optical splitting device 22 is utilized to achieve uniform splitting, and the structure of the optical splitting device 22 is as shown in fig. 9, but not limited to 8-path splitting shown in fig. 9, and may be set according to the actual laser beam quantity requirement and the subsequent specification and quantity of the optical splitter 21, and may be 2, 4, 8, and the like, or may be a special value other than the above-mentioned values. The optical splitting device 22 has the advantages that the primary optical fiber splitter 21 can be reduced, so that the light splitting is more uniform and the loss is less.
As shown in fig. 3-5, the present invention provides a system for splitting and polarization maintaining transmission of polarized light, which comprises a laser 51; at least one fiber coupler 41; the optical splitting module 20 for splitting the laser into multiple paths comprises an optical splitter 21, and an optical coupler 41 is arranged in front of the optical splitter 21; an optical fiber collimator 42 disposed behind the optical fiber splitter 21 and connected to the optical fiber splitter 21; a depolarization module 10 for changing the laser light into completely unpolarized light 13; and a polarizing module 30 disposed after the depolarizing module 10 for converting the laser light that becomes the completely unpolarized light 13 into polarized light.
The system of the invention firstly splits the laser light, retreats the polarization and then starts the polarization treatment or firstly retreats the polarization and then splits the light and then starts the polarization treatment, the laser light is firstly changed into the completely unpolarized light 13, then the completely unpolarized light 13 is changed into the linearly polarized light by the polarization module 30, the power loss is reduced, the system is used by the following system, before or after the laser light is changed into the completely unpolarized light 13, the laser light is divided into the required amount of multipath light, and then the multipath light is changed into the polarized light before the use, so that the power of each path of the used laser light is approximately equal and is the polarized light. Whether the polarization is split first or depolarized first, the laser light is changed into completely unpolarized light 13 and polarized before the transmission is finished, and therefore the polarization module 30 is disposed after the polarization depolarizing module 10 and at the end of the entire polarization maintaining transmission system. The polarizing module 30 in this embodiment may adopt a polarization beam splitter, the completely unpolarized light 13 is split into a horizontally polarized light and a vertically polarized light by the polarization beam splitter, and the powers of the two beams are completely the same. The laser 51 in the present invention refers to a device capable of emitting laser light in a broad sense, and the whole process starts with the laser light generated by the laser 51, not with the emission from the laser emitting device. In reality, the output interfaces of some laser emitting devices are optical fibers and are built in the optical fiber coupler 41, and when the processes of depolarization before beam splitting and then polarization are performed in the application process, the output interfaces of the laser emitting devices need to be connected with the optical fiber collimator 42 to lead out laser, and after depolarization by the depolarization module 10, the laser is led into the optical fiber splitter 21 through the other optical fiber coupler 41 to perform beam splitting; when the processes of splitting, backing, and then starting the polarization are performed, the output interface of the laser emitting device is directly connected with the optical fiber splitter 21 to split the light, and the optical fiber coupler 41 described in the present invention is the optical fiber coupler 41 built in the laser emitting device.
As shown in fig. 3, which is a schematic structural diagram of a system for performing a first depolarization and then light splitting, the depolarization module 10 is a depolarization unit 11, and is disposed in front of the optical fiber splitter 21, and the laser light passes through the depolarization unit 11 and then becomes a completely unpolarized light 13, and then is split into multiple paths of light by the light splitting module 20, and is subjected to a first depolarization and then light splitting process. More specifically, in an embodiment of a structure for performing a process of depolarization before splitting and then polarization, laser light emitted from a laser 51 is firstly subjected to polarization disturbance by a depolarizer 11 to become completely unpolarized light 13, the completely unpolarized light 13 enters an optical fiber splitter 21 through an optical fiber coupler 41 to be split into multiple paths of light, each path of laser light is transmitted to an optical fiber collimator 42 through an optical fiber, the optical fiber collimator 42 is connected with a polarization module 30, the emitted laser light is changed into linearly polarized light again, the polarization module 30 is a polarization beam splitter, the completely unpolarized light 13 is split into horizontally polarized light and vertically polarized light by the polarization beam splitter, and the powers of the two beams of light are completely the same.
As shown in fig. 4, which is a schematic structural diagram of a system for performing a first-splitting and second-splitting polarization, the polarization-canceling module 10 is a polarization-canceling device 11, and is disposed behind the fiber collimator 42, after the laser is split into multiple paths of light by the light-splitting module 20, each path of light is processed by the polarization-canceling device 11 to become a completely unpolarized light 13, and a first-splitting and second-splitting polarization process is performed. More specifically, in an embodiment of a structure for performing a first-splitting, backward polarization and then polarization processing, laser enters the fiber splitter 21 through the fiber coupler 41, and is split into a plurality of laser beams, each laser beam is transmitted to the fiber collimator 42, the fiber collimator 42 is connected to the depolarizer 11, the laser beam emitted from the fiber collimator 42 is changed into a completely unpolarized light 13, the polarization module 30 behind the depolarizer 11 changes the completely unpolarized light 13 into a linearly polarized light, the polarization module 30 is a polarization beam splitter, the completely unpolarized light 13 is split into a horizontally polarized light and a vertically polarized light by the polarization beam splitter, and the powers of the two beams are completely the same.
As shown in fig. 5, which is another schematic structural diagram of a system for performing a first-splitting and a second-splitting polarization, the polarization-canceling module 10 is a large-core multimode fiber 12 with a certain length, and is connected to a fiber splitter 21 in the light-splitting module 20, after entering the fiber splitter 21, the laser is split into multiple beams and enters the corresponding large-core multimode fibers 12, and the multiple beams are converted into completely unpolarized beams 13 during transmission, and then the first-splitting and second-splitting polarization processing is performed. More specifically, the laser enters the fiber splitter 21 through the fiber coupler 41, is divided into a plurality of beams of laser, then each beam of laser enters the corresponding large-core-diameter multimode fiber 12, and is converted into the completely unpolarized light 13 in the transmission process, and then is output through the fiber collimator 42, and is converted into polarized light through the polarization module 30, the polarization module 30 is a polarization beam splitter, the completely unpolarized light 13 is divided into horizontal polarized light and vertical polarized light through the polarization beam splitter, and the power of the two beams of light is completely the same. Experiments show that the large-core-diameter multimode optical fiber 12 has a core diameter of 400-800 micrometers and a length of more than meter level. The core diameter of the multimode fiber in the optical fiber branching unit 21 is 50 microns or 62.5 microns, the laser coupling efficiency from the multimode fiber with the thin core diameter to the multimode fiber with the thick core diameter is high, the optical fiber branching unit 21 and the multimode fiber 12 with the large core diameter are connected through a switching flange plate, and the optical fiber collimator 42 is connected with the multimode fiber 12 with the large core diameter.
as shown in fig. 7, the optical splitting module 20 of this embodiment includes a plurality of stages of optical splitters 21, the optical fiber coupler 41 is connected to the first stage of optical splitters 21, the laser or completely unpolarized light 13 enters the first stage of optical splitters 21 through the optical fiber coupler 41, and the split light enters the next stage of optical splitters 21 until the required path number of light is obtained. It will be understood by those skilled in the art that the number and specification of the optical splitters 21 are not limited in the embodiment of the present invention, and may be set according to the number of laser beams required in practical applications, for example, in the specific example shown in fig. 7, the content and features of the light splitting method according to the embodiment of the present invention are explained and disclosed by taking the example of splitting 8 lights by using the two-stage 2-way optical splitter 21, but splitting 8 lights by using the two-stage 2-way optical splitter 21 is not to be considered as limiting the content and scope of the light splitting method according to the preferred embodiment. Alternatively, in another possible example two of the light splitting method of the present embodiment, the adopted optical splitter 21 may also be, but not limited to, 4/8/16/32/64, or the like, or may also be a special value other than the above value, and due to the optimization of the optical splitter 21 itself, the number of stages may also be 3, 4, 5, or the like, so that the power deviation of each path may meet the requirements of the laser application system.
Since the optical splitter has a plurality of stages and may cause adverse effects such as optical power loss and splitting non-uniformity, the optical splitting module 20 preferably includes an optical splitting device 22, and the optical coupler 41 is disposed between the optical splitting device 22 and the plurality of stages of optical splitters 21. The laser beam emitted from the laser 51 is divided into n paths by the optical beam splitter 22, and the optical beam splitter 22 uses optical devices such as lenses, prisms, mirrors, etc. to divide the laser input into a plurality of laser beams and output them, and both the incident and the emitted laser beams are free space beams.
by combining the depolarization module 10, when the depolarization unit 11 is selected as the depolarization unit 10, the depolarization unit 11 and the optical splitting device 22 are both optical devices, and the installation methods thereof are two, one is to arrange the depolarization unit 11 between the laser 51 and the optical splitting device 22, the laser light is changed into completely unpolarized light 13 through the depolarization unit 11, then enters the optical splitting device 22 for preliminary splitting, and a plurality of completely unpolarized light 13 enters the next-stage optical splitter 21 through the subsequent optical fiber coupler 41 for further splitting; the other is to arrange the depolarizer 11 between the optical splitter 22 and the fiber coupler 41, after the laser is primarily split by the optical splitter 22, each beam of light goes through the depolarizer 11 to become completely unpolarized light 13, and then goes through the fiber coupler 41 to the next stage of fiber splitter 21 for further splitting. In practical applications, for some laser emitting devices with optical fibers as output interfaces, the optical fiber collimator 42 is required to be applied to lead out laser, and then the optical splitting device 22 is used to split the laser, and the existing optical splitting device 22 is utilized to achieve uniform splitting, and the structure of the optical splitting device 22 is as shown in fig. 9, but not limited to 8-path splitting shown in fig. 9, and may be set according to the actual laser beam quantity requirement and the subsequent specification and quantity of the optical splitter 21, and may be 2, 4, 8, and the like, or may be a special value other than the above-mentioned values. The optical splitting device 22 has the advantages that the primary optical fiber splitter 21 can be reduced, so that the light splitting is more uniform and the loss is less.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.
Claims (10)
1. A method for splitting polarized light and maintaining the transmission of the polarized light, comprising the steps of:
A depolarization step, setting a depolarization module to change laser into completely unpolarized light;
A light splitting step, namely setting a light splitting module, splitting laser or completely unpolarized light into multiple paths of light, and enabling the laser or completely unpolarized light to enter an optical fiber splitter through an optical fiber coupler and to be emitted from an optical fiber collimator;
And a polarizing step, setting a polarizing module, and converting the completely unpolarized light of each path into linearly polarized light for the required equipment.
2. The method for splitting polarized light and transmitting it with polarization maintaining according to claim 1, wherein in the step of depolarization, the depolarization module is a depolarizer,
the laser is changed into completely unpolarized light after passing through the depolarizer and then is divided into multiple paths of light through the light splitting module;
or
the depolarizer is arranged behind the optical fiber collimator, and after the laser is divided into multiple paths of light by the light splitting module, each path of light is processed by the depolarizer to become completely unpolarized light.
3. The method according to claim 1, wherein in the depolarization step, the depolarization module is a length of large-core multimode fiber connected to a fiber splitter in the light splitting module, and the laser light enters the fiber splitter and then is split into multiple beams of light, which enter the corresponding large-core multimode fibers, respectively, and then becomes completely unpolarized light.
4. the method for splitting polarized light and maintaining the transmission of the polarized light according to claim 1, 2 or 3, wherein in the splitting step, the splitting module comprises a plurality of stages of fiber splitters, the laser or completely unpolarized light enters the fiber splitter of the first stage through the fiber coupler, and the split light enters a plurality of fiber splitters of the next stage until the required path number of light is obtained.
5. the method according to claim 4, wherein in the splitting step, the splitting module further includes an optical splitting device, the optical splitting device is disposed in front of the multi-stage optical fiber splitters, laser light or completely unpolarized light is primarily split by the optical splitting device, and the primarily split light enters the first stage of optical fiber splitters through the optical fiber couplers and then enters the next stage of optical fiber splitters respectively until the required path number of light is obtained.
6. a system for splitting polarized light and transmitting the polarized light in a polarization-maintaining way is characterized by comprising
a laser;
At least one fiber coupler;
The light splitting module is used for splitting laser into multiple paths and comprises an optical fiber splitter, wherein the optical fiber coupler is arranged in front of the optical fiber splitter;
The optical fiber collimator is arranged behind the optical fiber branching unit and connected with the optical fiber branching unit;
the depolarization module is used for changing the laser light into completely unpolarized light; and
And the polarizing module is arranged behind the depolarization module and used for converting the laser light which becomes completely unpolarized light into polarized light.
7. The system for splitting polarized light and maintaining the transmission of the polarized light according to claim 6, wherein the polarization-removing module is a polarization-removing device disposed before the fiber splitter or after the fiber collimator.
8. The system for splitting polarized light and transmitting polarized light according to claim 6, wherein the polarization-removing module is a large-core multimode fiber having a certain length, connected to the fiber splitter, and disposed between the fiber splitter and the fiber collimator.
9. The system for splitting polarized light and maintaining polarization transmission according to claim 6, 7 or 8, wherein the splitting module comprises a plurality of stages of the fiber optic splitters, and the fiber couplers are connected with the first stage of the fiber optic splitters.
10. the system for splitting polarized light and maintaining polarization transmission according to claim 9, wherein the splitting module comprises an optical splitting device, and the fiber coupler is disposed between the optical splitting device and the multi-stage fiber splitter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810581644.2A CN110579886A (en) | 2018-06-07 | 2018-06-07 | Method and system for branching polarized light and polarization-maintaining transmission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810581644.2A CN110579886A (en) | 2018-06-07 | 2018-06-07 | Method and system for branching polarized light and polarization-maintaining transmission |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110579886A true CN110579886A (en) | 2019-12-17 |
Family
ID=68808692
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810581644.2A Pending CN110579886A (en) | 2018-06-07 | 2018-06-07 | Method and system for branching polarized light and polarization-maintaining transmission |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110579886A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101510663A (en) * | 2009-03-06 | 2009-08-19 | 苏州大学 | Polarization dual wavelength fiber-optical ultrashort pulse laser |
| CN101684925A (en) * | 2008-09-23 | 2010-03-31 | 北京中视中科光电技术有限公司 | Area light source |
| CN102487175A (en) * | 2010-12-27 | 2012-06-06 | 北京国科世纪激光技术有限公司 | Laser output method and laser output apparatus |
| CN102842844A (en) * | 2012-08-28 | 2012-12-26 | 常州奥镭光电科技有限公司 | Natural polarization state single wavelength light source and method |
| CN105161961A (en) * | 2015-09-30 | 2015-12-16 | 中国科学院合肥物质科学研究院 | Micro-pulse laser radar light source with high pulse energy |
| CN106842605A (en) * | 2017-04-11 | 2017-06-13 | 中国科学技术大学 | Light-dividing device based on polarization spectroscope |
| CN208488603U (en) * | 2018-06-07 | 2019-02-12 | 杭州昕磁科技有限公司 | A kind of polarization optical branching and polarization-maintaining Transmission system |
-
2018
- 2018-06-07 CN CN201810581644.2A patent/CN110579886A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101684925A (en) * | 2008-09-23 | 2010-03-31 | 北京中视中科光电技术有限公司 | Area light source |
| CN101510663A (en) * | 2009-03-06 | 2009-08-19 | 苏州大学 | Polarization dual wavelength fiber-optical ultrashort pulse laser |
| CN102487175A (en) * | 2010-12-27 | 2012-06-06 | 北京国科世纪激光技术有限公司 | Laser output method and laser output apparatus |
| CN102842844A (en) * | 2012-08-28 | 2012-12-26 | 常州奥镭光电科技有限公司 | Natural polarization state single wavelength light source and method |
| CN105161961A (en) * | 2015-09-30 | 2015-12-16 | 中国科学院合肥物质科学研究院 | Micro-pulse laser radar light source with high pulse energy |
| CN106842605A (en) * | 2017-04-11 | 2017-06-13 | 中国科学技术大学 | Light-dividing device based on polarization spectroscope |
| CN208488603U (en) * | 2018-06-07 | 2019-02-12 | 杭州昕磁科技有限公司 | A kind of polarization optical branching and polarization-maintaining Transmission system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108054624B (en) | A kind of optical fiber laser with anti-fibre core reflected light function | |
| JPH04371911A (en) | Optical isolator and fiber optical amplifier with added rare earth | |
| US20040196539A1 (en) | Fiber amplifier and control method thereof | |
| CN109273986A (en) | A kind of semiconductor laser conjunction binding structure | |
| CN102820607B (en) | Signal and pumping laser hybrid integrated device | |
| CN203084238U (en) | Integrated optical device | |
| US9322993B1 (en) | All pump combiner with cladless inputs | |
| US9768581B2 (en) | Pump and signal combiner for high numerical aperture use | |
| CN113783091A (en) | Optical fiber isolator | |
| CN203414622U (en) | Backward mixing device of erbium doped fiber amplifier | |
| CN110579886A (en) | Method and system for branching polarized light and polarization-maintaining transmission | |
| CN204575907U (en) | A kind of forward direction optoelectric hybrid device of Erbium-Doped Fiber Amplifier (EDFA) | |
| CN102130416B (en) | Laser apparatus | |
| JP5635654B1 (en) | Multi-core fiber connection parts | |
| CN208488603U (en) | A kind of polarization optical branching and polarization-maintaining Transmission system | |
| WO2022166824A1 (en) | Pumping light source, optical amplification system, roadm, and pumping light providing method | |
| CN204575906U (en) | The backward optoelectric hybrid device of Erbium-Doped Fiber Amplifier (EDFA) | |
| CN112260063B (en) | Single tube space beam combining device of semiconductor laser | |
| JP2017528769A (en) | Optical signal modulation apparatus and system | |
| US20040001660A1 (en) | Crosstalk improvement module and its using method | |
| CN110220509B (en) | Hybrid integrated narrow linewidth laser system for high-precision fiber-optic gyroscope | |
| CN111999806A (en) | Method and functional device for coupling single mode and multimode optical fiber modes | |
| JPH11112065A (en) | Optical fiber amplifier | |
| US9362709B1 (en) | Optical fiber laser architecture with partitioned pump and signal coupling | |
| CN208239737U (en) | A kind of laser light source mould group |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20220513 Address after: 310000 room 506, Huachuang building, No. 511, Jianye Road, Changhe street, Binjiang District, Hangzhou City, Zhejiang Province Applicant after: HANGZHOU XINCI TECHNOLOGY CO.,LTD. Applicant after: Hangzhou Liangci Technology Co., Ltd Address before: 310000 room 506, Huachuang building, No. 511, Jianye Road, Changhe street, Binjiang District, Hangzhou City, Zhejiang Province Applicant before: HANGZHOU XINCI TECHNOLOGY CO.,LTD. |
|
| TA01 | Transfer of patent application right |