Optical fiber nutation coupling device based on double-optical-wedge scanning and control method thereof

Abstract

The invention provides an optical fiber nutation coupling device based on double-optical wedge scanning and a control method thereof, and relates to the technical field of free space optical communication, the device comprises a shell, a first wedge lens group, a second wedge lens group, a coupling lens group and an optical fiber; the first wedge lens group, the second wedge lens group and the coupling lens group are arranged in the shell along a light path; the receiving end of the optical fiber is arranged at one end, close to the coupling lens group, of the shell; both the first wedge lens group and the second wedge lens group are rotatably mounted in the shell, the first wedge lens group is provided with a first optical wedge, the second wedge lens group is provided with a second optical wedge, the vertical surfaces of the first optical wedge and the second optical wedge are parallel and opposite, the wedge surfaces of the first optical wedge and the second optical wedge are opposite, and the first optical wedge and the second optical wedge rotate in the reverse direction and / or the same direction. Controlling the light spot to perform nutation scanning on the coupling mirror group; the coupling mirror group is used for focusing the target light beam into a light spot to be emitted to the optical fiber, and the light spot is emitted into the optical fiber when overlapped with the receiving end of the optical fiber. The device is compact in structure, small in size, light in weight and low in power consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of free space optical communication, and in particular to a fiber optic nutation coupling device based on double optical wedge scanning and a control method thereof. Background Art

[0002] In recent years, with the increasing maturity of spaceborne laser communication terminal technology and the successful establishment of in-orbit links between satellites and between satellites and the ground, a wave of enthusiasm for inter-satellite laser communication has been set off in the field of free space optical communication technology, and the commercialization of laser communication terminals has become increasingly urgent. Due to optical machining, alignment deviation, micro-deformation of the mechanical structure caused by on-orbit temperature and stress changes of the satellite platform, platform vibration and the influence of system transceiver non-coaxiality, it is extremely difficult to couple the weak signal light entering the optical system into a 9um single-mode optical fiber. Therefore, an efficient and stable coupling technology for free space optical coupling into a single-mode optical fiber is the prerequisite and guarantee for the realization of high-speed long-distance laser communication technology, and it is also a key technology in space laser communication, which urgently needs to be solved, so as to ensure the rapid and stable improvement of the coupling efficiency, and further ensure the quality of free space laser communication.

[0003] Existing fiber optic nutation coupling devices usually use a fast steering mirror as the nutation mirror, and adjust the incident light angle by adjusting the fast steering mirror, so as to realize nutation coupling. However, the weight, volume and power consumption of the fast steering mirror cannot be ignored. Therefore, it is of great significance to adopt a new method to perform adaptive free space optical-single mode fiber coupling with a structure that does not increase the fast steering mirror and has a relatively simple structure, high system integration and strong space utilization. Summary of the Invention

[0004] The purpose of the present invention is to provide a fiber optic nutation coupling device based on double optical wedge scanning and a control method thereof, so as to solve at least one of the above technical problems existing in the prior art.

[0005] In a first aspect, to solve the above technical problems, a fiber optic nutation coupling device based on double optical wedge scanning provided by the present invention includes: a housing, a first wedge mirror group, a second wedge mirror group, a coupling mirror group and an optical fiber; The housing is cylindrical, the first wedge mirror group, the second wedge mirror group and the coupling mirror group are arranged in the housing in sequence along the optical path, the receiving end of the optical fiber is arranged at one end of the housing close to the coupling mirror group, and when in use, the target beam is incident parallelly, and successively passes through the first wedge mirror group, the second wedge mirror group and the coupling mirror, and is directed to the optical fiber; The first wedge prism group and the second wedge prism group are both rotatably installed in the housing. The first wedge prism group is provided with a first optical wedge, and the second wedge prism group is provided with a second optical wedge. The vertical surfaces (i.e., the mirror surfaces perpendicular to the optical axis) of the first optical wedge and the second optical wedge are parallel and face each other, and the wedge surfaces of the first optical wedge and the second optical wedge face away from each other. During use, the target beam sequentially passes through the first optical wedge and the second optical wedge, exits from the wedge surface of the second optical wedge, and irradiates on the coupling mirror group to form a light spot. By rotating the first optical wedge and the second optical wedge in opposite and / or the same directions, a deflected free-space optical axis angle is formed, thereby controlling the nutation scanning of the light spot on the coupling mirror group; The coupling mirror group is used for focusing the target beam. The target beam converges into a light point through the coupling mirror group and shoots towards the optical fiber, and enters the optical fiber when the light point overlaps with the receiving end of the optical fiber.

[0006] In this application, a first wedge prism group, a second wedge prism group, and a coupling mirror group are sequentially arranged in the housing. The receiving end of the optical fiber is arranged at one end of the housing close to the coupling mirror group. When the position of the optical fiber is unknown, the first wedge prism group and the second wedge prism group are adjusted to control the nutation scanning of the light spot on the coupling mirror group. By measuring the optical output coupling efficiency of the target beam coupled into the optical fiber, the rotation direction and rotation angle of the first wedge prism group and the second wedge prism group are feedback-adjusted to ensure a high and stable optical output coupling efficiency and reduce power consumption.

[0007] Further, the fiber nutation coupling device based on double optical wedge scanning further includes a beam reducing mirror group. The beam reducing mirror group is arranged in the housing along the optical path and is arranged on the side of the first wedge prism group away from the second wedge prism group for compressing the target beam. During use, the target beam is incident parallelly, compressed by the beam reducing mirror group, and exits parallelly; In this application, the beam reducing mirror group is used to reduce the light passing aperture, greatly reducing the sizes of the first wedge prism group and the second wedge prism group, thereby reducing the size of the fiber nutation coupling device based on double optical wedge scanning and making the structure of the fiber nutation coupling device based on double optical wedge scanning more compact.

[0008] Further, the first wedge prism group and the second wedge prism group face each other.

[0009] Further, both the first wedge prism group and the second wedge prism group include: an optical wedge, a wedge prism barrel, and a bearing; The first optical wedge is the optical wedge of the first wedge prism group, and the first optical wedge is installed in the wedge prism barrel of the first wedge prism group; The second optical wedge is the optical wedge of the second wedge prism group, and the second optical wedge is installed in the wedge prism barrel of the second wedge prism group; A bearing is sleeved on the outer side of the wedge lens barrel, and the bearing is installed in the housing. The wedge lens barrel is rotatably installed in the housing through the bearing.

[0010] Preferably, a first outer flange is provided on the outer side of the wedge lens barrel, and one end surface of the inner ring of the bearing abuts against the first outer flange; The wedge lens barrel is provided with a first bearing pressure cover at one end close to the bearing, the first bearing pressure cover abuts against the other end surface of the bearing inner ring, and the bearing is fixed on the first outer flange by the first bearing pressure cover.

[0011] Preferably, a first inner flange and a second inner flange are provided on the inner side of the shell; The first inner flange is arranged on the other side of the bearing, and the other end surface of the outer ring of the bearing abuts against the first inner flange; The second inner flange is arranged on one side of the bearing, a second bearing pressure cover is installed on the second inner flange, the second bearing pressure cover abuts against one end surface of the bearing outer ring, and the bearing is fixed on the first inner flange by the second bearing pressure cover.

[0012] Furthermore, the first wedge lens group and the second wedge lens group each include a motor, and the motor is mounted on the outer side of the wedge lens barrel and is used to drive the wedge lens barrel to rotate, thereby driving the optical wedge to rotate.

[0013] Preferably, a third inner flange and a fourth inner flange are further provided on the inner side of the shell, the third inner flange and the fourth inner flange are both provided on the side of the second inner flange away from the first inner flange, and the third inner flange is provided between the second inner flange and the fourth inner flange; One side end surface of the motor abuts against the third inner flange; A motor pressure cover is installed on the fourth inner flange, and the motor pressure cover abuts against the other end surface of the motor. The motor is pressed and fixed on the third inner flange by the motor pressure cover.

[0014] Preferably, the motor is typically a brushless motor.

[0015] Furthermore, the first wedge lens group and the second wedge lens group each include an encoder, the encoder is mounted on the outside of the wedge lens barrel, the encoder is electrically connected to the motor, and is used to detect the rotation direction and rotation angle of the optical wedge.

[0016] Furthermore, the optical fiber is usually a single-mode optical fiber.

[0017] Further, the fiber nutation coupling device based on double optical wedge scanning further includes an actuator, which is movably installed along the axial direction at one end of the housing close to the coupling mirror group. The receiving end of the optical fiber is installed on the actuator, and the actuator is used to adjust the distance between the coupling mirror group and the receiving end of the optical fiber to ensure that the focus of the target beam converged by the coupling mirror group and the receiving end of the optical fiber are located on the same plane.

[0018] In a second aspect, based on the same inventive concept, the present invention also provides a control method for the fiber nutation coupling device based on double optical wedge scanning as described above, including a control method for the fiber nutation coupling device based on double optical wedge scanning when the position of the optical fiber is unknown or lost, including: Step 1: Control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction respectively at their respective specified speeds and accelerations, so as to control the light spot to perform a fast and comprehensive scan on the coupling mirror group 4 to 5 times. Use the coupling mirror group to couple the target beam to the optical fiber, detect whether there is an optical signal coupled into the optical fiber, and feedback control the rotation of the first optical wedge and the second optical wedge according to the detection information until it is detected that there is an optical signal coupled into the optical fiber; Step 2: Based on the feedback information of the optical signal coupled into the optical fiber detected, combined with the fast and comprehensive scan trajectory, roughly estimate the position of the receiving end of the optical fiber; according to the position of the receiving end of the optical fiber obtained by the rough estimate, control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction respectively at their respective specified speeds and accelerations by a small angle, so as to control the light spot to perform a preliminary scan on the coupling mirror group. Use the coupling mirror group to couple the target beam to the optical fiber, detect the optical output coupling efficiency of the target beam coupled into the optical fiber, and feedback control the rotation of the first optical wedge and the second optical wedge according to the detection information until the optical output coupling efficiency of the target beam coupled into the optical fiber is detected to reach 10%, and complete the preliminary coupling; Step 3: Based on the feedback information of the optical output coupling efficiency of the target beam coupled into the optical fiber detected, combined with the fast and comprehensive scan trajectory, adjust the rotation step of the first optical wedge and the second optical wedge, control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction respectively at their respective specified speeds and accelerations by a tiny angle, so as to control the light spot to perform a precise scan on the coupling mirror group. Use the coupling mirror group to couple the target beam to the optical fiber, detect the optical output coupling efficiency of the target beam coupled into the optical fiber, and feedback control the rotation of the first optical wedge and the second optical wedge according to the detection information until the optical output coupling efficiency of the target beam coupled into the optical fiber is detected to reach the maximum, and complete the precise alignment; Step 4: Turn on the communication. While communicating using the optical signal received by the optical fiber, monitor the stability of the feedback optical signal in real time. Pause the communication when the optical output coupling efficiency of the target light beam coupled into the optical fiber is less than 45%, and repeat Step 3 to ensure the stability of the communication.

[0019] Further, the control method of the fiber optic nutation coupling device based on double optical wedge scanning further includes the control method of the fiber optic nutation coupling device based on double optical wedge scanning when importing the optical fiber position reference information, including: Step 1': Obtain the optical fiber position reference information; according to the obtained optical fiber position reference information, control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction at small angles respectively according to their respective specified speeds and accelerations, so as to control the spot to perform a preliminary scan on the coupling mirror group, use the coupling mirror group to couple the target light beam to the optical fiber, detect the optical output coupling efficiency of the target light beam coupled into the optical fiber, and feedback and control the rotation of the first optical wedge and the second optical wedge according to the detection information until the optical output coupling efficiency of the target light beam coupled into the optical fiber is detected to reach 10%, and complete the preliminary coupling; After Step 1' is completed, execute Step 3 and Step 4.

[0020] Adopting the above technical solution, the present invention has the following beneficial effects: The fiber optic nutation coupling device based on double optical wedge scanning and its control method provided by the present invention compress the light beam through a beam reducing mirror group, reduce the light passing aperture, greatly reduce the size of the device, and have a more compact structure, small volume and light weight; when the position of the optical fiber is unknown, the spot is controlled to perform nutation scanning on the coupling mirror group by adjusting the first wedge mirror group and the second wedge mirror group, and the rotation direction and rotation angle of the first wedge mirror group and the second wedge mirror group are feedback adjusted according to the optical output coupling efficiency, ensuring a high and stable optical output coupling efficiency and reducing power consumption. Description of the Drawings

[0021] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a cross-sectional view of the fiber optic nutation coupling device based on double optical wedge scanning provided by the embodiment of the present invention; Figure 2 It is Figure 1 The cross-sectional view of the first wedge mirror group and the second wedge mirror group shown; Figure 3 It isFigure 1 The front view of the beam-shrinking lens group shown; Figure 4 is Figure 3 The schematic three-dimensional structure diagram of the beam-shrinking lens group shown on the light incident side; Figure 5 is Figure 4 The exploded view of the beam-shrinking lens group shown; Figure 6 is Figure 3 The schematic three-dimensional structure diagram of the beam-shrinking lens group shown on the light exit side; Figure 7 is Figure 1 The front view of the first wedge lens group shown; Figure 8 is Figure 7 The schematic three-dimensional structure diagram of the first wedge lens group shown on the wedge surface side of the optical wedge; Figure 9 is Figure 8 The exploded view of the first wedge lens group shown; Figure 10 is Figure 7 The schematic three-dimensional structure diagram of the first wedge lens group shown on the vertical surface side of the optical wedge; Figure 11 is Figure 1 The front view of the coupling lens group shown; Figure 12 is Figure 11 The schematic three-dimensional structure diagram of the coupling lens group shown on the light incident side; Figure 13 is Figure 12 The exploded view of the coupling lens group shown; Figure 14 is Figure 11 The schematic three-dimensional structure diagram of the coupling lens group shown on the light exit side; Figure 15 is Figure 1 The front view of the fiber nutation coupling device based on double optical wedge scanning shown; Figure 16 is Figure 1 The front view of the housing shown; Figure 17 is Figure 1 The sectional view of the housing shown; Figure 18 is Figure 1 The front view of the actuator shown; Figure 19 is Figure 18 The schematic three-dimensional structure diagram of the actuator shown on the light incident side; Figure 20 is Figure 18Schematic three-dimensional structure diagram of the actuator on the light-emitting side; Figure 21 Flowchart of the control method for the fiber optic nutation coupling device based on double optical wedge scanning provided by the embodiment of the present invention when the fiber optic position is unknown or lost; Figure 22 Flowchart of the control method for the fiber optic nutation coupling device based on double optical wedge scanning provided by the embodiment of the present invention when importing fiber optic position reference information.

[0023] Reference numerals: 1 - housing; 11 - first inner flange; 12 - second inner flange; 13 - third inner flange; 14 - fourth inner flange; 15 - fifth inner flange; 16 - sixth inner flange; 2 - beam reducing lens group; 21 - first lens; 22 - first spacer ring; 23 - first nut; 31a - first optical wedge; 31b - second optical wedge; 32 - wedge lens barrel; 321 - first outer flange; 33 - bearing; 331 - first bearing gland; 332 - second bearing gland; 34 - motor; 341 - motor gland; 35 - encoder; 4 - coupling lens group; 41 - second lens; 42 - second spacer ring; 43 - second nut; 5 - optical fiber; 6 - actuator. Detailed implementation manners

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0027] The following further explains and illustrates the present invention in combination with specific embodiments.

[0028] It should also be noted that the following specific embodiments or specific implementation manners are a series of optimized setting manners listed by the present invention to further explain the specific invention content, and these setting manners can be combined with each other or used in association with each other.

[0029] Embodiment 1 As Figures 1 - 20 shown, a fiber optic nutation coupling device based on double optical wedge scanning provided in this embodiment includes: a housing 1, a first wedge lens group, a second wedge lens group, a coupling lens group 4, and an optical fiber 5; the housing 1 is cylindrical, the first wedge lens group, the second wedge lens group, and the coupling lens group 4 are arranged in the housing 1 in sequence along the optical path, the receiving end of the optical fiber 5 is arranged at one end of the housing 1 close to the coupling lens group 4, and during use, the target beam is incident parallelly and sequentially passes through the first wedge lens group, the second wedge lens group, and the coupling lens, and is directed towards the optical fiber 5; the target beam is usually free space light incident parallelly; the first wedge lens group and the second wedge lens group are rotatably installed in the housing 1, the first wedge lens group is provided with a first optical wedge 31a, the second wedge lens group is provided with a second optical wedge 31b, the vertical plane (i.e., the mirror surface perpendicular to the optical axis) of the first optical wedge 31a is parallel and facing each other with the vertical plane of the second optical wedge 31b, and the wedge surface of the first optical wedge 31a is arranged back to back with the wedge surface of the second optical wedge 31b. During use, the target beam sequentially passes through the first optical wedge 31a and the second optical wedge 31b, exits from the wedge surface of the second optical wedge 31b, and irradiates on the coupling lens group 4 to form a light spot. By rotating the first optical wedge 31a and the second optical wedge 31b in opposite and / or the same direction, a deflected free space optical axis angle is formed, so as to control the nutation scanning of the light spot on the coupling lens group 4; the coupling lens group 4 is used for focusing the target beam, and the target beam converges into a light point through the coupling lens group 4 and is directed towards the optical fiber 5, and enters the optical fiber 5 when the light point overlaps with the receiving end of the optical fiber 5.

[0030] The present application sequentially arranges a first wedge lens group, a second wedge lens group and a coupling lens group 4 in a housing 1, arranges a receiving end of an optical fiber 5 at one end of the housing 1 close to the coupling lens group 4, and when the position of the optical fiber 5 is unknown, adjusts the first wedge lens group and the second wedge lens group to control the light spot to perform nutation scanning on the coupling lens group 4, and feedback adjusts the rotation direction and rotation angle of the first wedge lens group and the second wedge lens group by measuring the light output coupling efficiency of the target light beam coupled into the optical fiber 5, thereby ensuring that the light output coupling efficiency is high and stable and reducing power consumption.

[0031] Reference Figure 1 As shown, on the basis of the above technical solution, it is further preferred that the optical fiber nutation coupling device based on dual wedge scanning also includes a beam reducing mirror group 2, which is arranged in the housing 1 along the optical path and is arranged on the side of the first wedge mirror group away from the second wedge mirror group, and is used for compressing the target light beam. When in use, the target light beam is incident in parallel, compressed by the beam reducing mirror group 2, and emitted in parallel; the present application reduces the clear aperture by the beam reducing mirror group 2, greatly reduces the size of the first wedge mirror group and the second wedge mirror group, thereby reducing the size of the optical fiber nutation coupling device based on dual wedge scanning, making the structure of the optical fiber nutation coupling device based on dual wedge scanning more compact.

[0032] Reference Figure 2 As shown, further, the first wedge mirror group and the second wedge mirror group are arranged facing each other.

[0033] Reference Figures 7 - 10 As shown (since the second wedge mirror group has the same structure as the first wedge mirror group and is arranged facing each other, Figures 7 - 10 It can also be used as a structural schematic diagram of the second wedge lens group). In this embodiment, the first wedge lens group and the second wedge lens group both include: an optical wedge, a wedge lens barrel 32 and a bearing 33; the first optical wedge 31a is the optical wedge of the first wedge lens group, and the first optical wedge 31a is installed in the wedge lens barrel 32 of the first wedge lens group; the second optical wedge 31b is the optical wedge of the second wedge lens group, and the second optical wedge 31b is installed in the wedge lens barrel 32 of the second wedge lens group; the two wedge lens barrels 32 are both provided with bearings 33 on adjacent sides, and the bearings 33 are installed in the housing 1, and the wedge lens barrel 32 is rotatably installed in the housing 1 through the bearings 33.

[0034] More preferably, a first outer flange 321 is provided on the outer side of the wedge barrel 32, and one side end face of the inner ring of the bearing 33 abuts against the first outer flange 321; a first bearing pressure cover 331 is installed at the end of the wedge barrel 32 close to the bearing 33, and the first bearing pressure cover 331 abuts against the other side end face of the inner ring of the bearing 33, and the bearing 33 is pressed and fixed on the first outer flange 321 by the first bearing pressure cover 331.

[0035] More preferably, a first inner flange 11 and a second inner flange 12 are provided inside the housing 1; the first inner flange 11 is disposed on the other side of the bearing 33, and the other end face of the outer ring of the bearing 33 abuts against the first inner flange 11; the second inner flange 12 is disposed on one side of the bearing 33, and a second bearing gland 332 is mounted on the second inner flange 12, and the second bearing gland 332 abuts against the one end face of the outer ring of the bearing 33, and the bearing 33 is pressed and fixed on the first inner flange 11 by the second bearing gland 332.

[0036] Further, both the first wedge prism group and the second wedge prism group further include a motor 34, and the motor 34 is sleeved on the side of the wedge prism barrel 32 away from the bearing 33 for driving the wedge prism barrel 32 to rotate, thereby driving the optical wedge to rotate.

[0037] More preferably, a third inner flange 13 and a fourth inner flange 14 are further provided inside the housing 1, and both the third inner flange 13 and the fourth inner flange 14 are disposed on the side of the second inner flange 12 away from the first inner flange 11, and the third inner flange 13 is disposed between the second inner flange 12 and the fourth inner flange 14; one end face of the motor 34 abuts against the third inner flange 13; a motor gland 341 is mounted on the fourth inner flange 14, and the motor gland 341 abuts against the other end face of the motor 34, and the motor 34 is pressed and fixed on the third inner flange 13 by the motor gland 341.

[0038] In this embodiment, the motor 34 is usually a brushless motor such as a DC torque motor or a DC servo motor. Except for the DC torque motor, other types of brushless motors need to drive the wedge prism barrel 32 to rotate by setting corresponding transmission components.

[0039] Further, both the first wedge prism group and the second wedge prism group further include an encoder 35, and the encoder 35 is mounted on the end face of the wedge prism barrel 32 away from the bearing 33, and the encoder 35 is electrically connected to the motor 34 for detecting the rotation direction and rotation angle of the optical wedge.

[0040] More preferably, the encoder 35 is usually a grating encoder such as a reflective grating encoder or a transmissive grating encoder. The grating encoder has a fast response and high precision, and the measurement precision is generally at the micron and arcsecond levels. The grating encoder usually consists of a light source, a main grating, an indicating grating (i.e., a secondary grating), and a detector. The main grating and the indicating grating are installed in parallel and separated. There is a certain rotation angle between the planes where the main grating and the indicating grating are located. After parallel light perpendicularly irradiates the main grating and the indicating grating and diffraction occurs, Moiré fringes will appear. The amount of movement can be obtained by measuring the change of the Moiré fringes.

[0041] Referring to Figures 3 - 6 as shown (the outer thread of the first nut 23 is not shown in the figure), more preferably, a fifth inner flange 15 is further provided on the inner side of the housing 1. The fifth inner flange 15 is provided on the side of the first wedge lens group facing away from the second wedge lens group. One side of the beam expander lens group 2 abuts against the fifth inner flange 15. A first nut 23 is provided on the other side of the beam expander lens group 2. The outer side of the first nut 23 is axially installed in the housing 1 through a thread. The first nut 23 abuts against the other side of the beam expander lens group 2. The beam expander lens group 2 is pressed and fixed on the fifth inner flange 15 by the first nut 23.

[0042] In this embodiment, the beam expander lens group 2 is formed by stacking several first lenses 21. The several first lenses 21 are arranged along the optical path. A first spacer 22 is provided between adjacent two of the first lenses 21 for separating the adjacent two first lenses 21, and the distance between the adjacent two first lenses 21 is set by the first spacer 22.

[0043] Referring to Figures 11 - 14 as shown (the outer thread of the second nut 43 is not shown in the figure), more preferably, a sixth inner flange 16 is further provided on the inner side of the housing 1. The sixth inner flange 16 is provided on the side of the second wedge lens group facing away from the first wedge lens group. One side of the coupling lens group 4 abuts against the sixth inner flange 16. A second nut 43 is provided on the other side of the coupling lens group 4. The outer side of the second nut 43 is axially installed in the housing 1 through a thread. The second nut 43 abuts against the other side of the coupling lens group 4. The coupling lens group 4 is pressed and fixed on the sixth inner flange 16 by the second nut 43.

[0044] In this embodiment, the coupling lens group 4 is formed by stacking several second lenses 41. The several second lenses 41 are arranged along the optical path. A second spacer 42 is provided between adjacent two of the second lenses 41 for separating the adjacent two second lenses 41, and the distance between the adjacent two second lenses 41 is set by the second spacer 42.

[0045] In this embodiment, the optical fiber 5 is usually a single-mode optical fiber, and the mode field diameter of the optical fiber 5 (1 / e 2 ) @ 1550 nm: 10.4 μm.

[0046] Referring to Figures 18 - 20 As shown, further, the optical fiber nutation coupling device based on double optical wedge scanning further includes an actuator 6. The actuator 6 is movably mounted along the axial direction at one end of the housing 1 close to the coupling lens group 4. The receiving end of the optical fiber 5 is mounted on the actuator 6. The actuator 6 is used to adjust the distance between the coupling lens group 4 and the receiving end of the optical fiber 5, so as to ensure that the focus of the target beam converged by the coupling lens group 4 and the receiving end of the optical fiber 5 are located on the same plane.

[0047] Moreover, the actuator 6 is connected to a side port of the housing 1 close to the coupling lens group 4 by a threaded manner. During use, the actuator 6 is twisted, and the actuator 6 adjusts the distance between the coupling lens group 4 and the receiving end of the optical fiber 5 through the thread.

[0048] The present invention compresses the light beam through the beam reducing lens group 2, reduces the light passing aperture, greatly reduces the size of the device, and has a more compact structure, small volume and light weight; when the position of the optical fiber 5 is unknown, the spot is controlled to perform nutation scanning on the coupling lens group 4 by adjusting the first wedge lens group and the second wedge lens group, and the rotation direction and rotation angle of the first wedge lens group and the second wedge lens group are feedback adjusted according to the light output coupling efficiency, so as to ensure a high and stable light output coupling efficiency and reduce power consumption.

[0049] Embodiment 2 As Figures 21 - 22 shown, a control method for the optical fiber nutation coupling device based on double optical wedge scanning provided in this embodiment includes: a control method for the optical fiber nutation coupling device based on double optical wedge scanning when the position of the optical fiber is unknown or lost, including: Step 1: Control the motors of the first wedge lens group and the second wedge lens group to drive the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction respectively according to their respective specified speeds and accelerations, so as to control the spot to perform a fast and comprehensive scan on the coupling lens group 4 to 5 times. The coupling lens group is used to couple the target beam to the optical fiber, and it is detected whether there is an optical signal coupled into the optical fiber. According to the detection information, the rotation of the first optical wedge and the second optical wedge is feedback controlled until it is detected that there is an optical signal coupled into the optical fiber; if it is not detected that there is an optical signal coupled into the optical fiber, repeat Step 1; Step 2: Based on the feedback information of the optical signal coupled into the optical fiber, combined with the fast and comprehensive scanning trajectory, roughly estimate the position of the optical fiber receiving end; according to the position of the optical fiber receiving end obtained from the rough estimate, control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite and / or the same direction with a small step angle of 10 arcseconds respectively at their respective specified speeds and accelerations, so as to control the spot to perform a preliminary scan on the coupling mirror group, use the coupling mirror group to couple the target beam to the optical fiber, detect the optical output coupling efficiency of the target beam coupled into the optical fiber, and control the rotation of the first optical wedge and the second optical wedge according to the detected information feedback until the optical output coupling efficiency of the target beam coupled into the optical fiber reaches 10%, and complete the preliminary coupling; if the optical output coupling efficiency of the target beam coupled into the optical fiber is not reached 10%, repeat Step 2; Step 3: Based on the feedback information of the optical output coupling efficiency of the target beam coupled into the optical fiber, combined with the fast and comprehensive scanning trajectory, adjust the rotation step of the first optical wedge and the second optical wedge, control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite and / or the same direction with a tiny step angle of 2 arcseconds respectively at their respective specified speeds and accelerations, so as to control the spot to perform a precise scan on the coupling mirror group, use the coupling mirror group to couple the target beam to the optical fiber, detect the optical output coupling efficiency of the target beam coupled into the optical fiber, and control the rotation of the first optical wedge and the second optical wedge according to the detected information feedback until the optical output coupling efficiency of the target beam coupled into the optical fiber reaches 50%, and complete the precise alignment; if the optical output coupling efficiency of the target beam coupled into the optical fiber is not reached 50%, repeat Step 3; Step 4: Turn on the communication, while using the optical signal received by the optical fiber for communication, monitor the stability of the feedback optical signal in real time, and pause the communication when the optical output coupling efficiency of the target beam coupled into the optical fiber is less than 45%, and repeat Step 3 to ensure the stability of the communication.

[0050] Refer to Figure 22 As shown, more preferably, the control method of the optical fiber nutation coupling device based on double optical wedge scanning further includes the control method of the optical fiber nutation coupling device based on double optical wedge scanning when importing the optical fiber position reference information, including: Step 1': Obtain the fiber position reference information; according to the obtained fiber position reference information, control the motors of the first wedge mirror group and the second wedge mirror group to drive the first optical wedge and the second optical wedge to rotate in opposite and / or the same direction at a small step angle of 10 arcseconds respectively at their respective specified speeds and accelerations, so as to control the spot to perform a preliminary scan on the coupling mirror group, use the coupling mirror group to couple the target beam to the optical fiber, detect the optical output coupling efficiency of the target beam coupled into the optical fiber, and feedback control the rotation of the first optical wedge and the second optical wedge according to the detection information until the optical output coupling efficiency of the target beam coupled into the optical fiber reaches 10%, and complete the preliminary coupling; if it is detected that the optical output coupling efficiency of the target beam coupled into the optical fiber does not reach 10%, repeat the above Step 1'. After the above Step 1' is completed, perform the above Step 3 and Step 4.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fiber nutation coupling device based on double wedge scanning, characterized in that: include: A housing, a first wedge mirror group, a second wedge mirror group, a coupling mirror group and an optical fiber; The housing is cylindrical, the first wedge lens group, the second wedge lens group and the coupling lens group are sequentially arranged in the housing along the optical path, the receiving end of the optical fiber is arranged at one end of the housing close to the coupling lens group, and when in use, the target light beam is incident in parallel, passes through the first wedge lens group, the second wedge lens group and the coupling lens in sequence, and is emitted to the optical fiber; The first wedge mirror group and the second wedge mirror group are both rotatably installed in the housing, the first wedge mirror group is provided with a first optical wedge, and the second wedge mirror group is provided with a second optical wedge, the vertical plane of the first optical wedge is parallel to the vertical plane of the second optical wedge and is arranged opposite to each other, and the wedge surface of the first optical wedge is arranged opposite to the wedge surface of the second optical wedge, and is used to control the light spot to nutate and scan on the coupling mirror group by rotating the first optical wedge and the second optical wedge in opposite directions and / or in the same direction; The coupling mirror assembly is used to focus the target light beam into a light spot and emit it to the optical fiber, and when the light spot overlaps with the receiving end of the optical fiber, it is emitted into the optical fiber.

2. The optical fiber nutation coupling device based on double wedge scanning according to claim 1, characterized in that: It also includes a beam reducing mirror group, which is arranged in the housing along the optical path and is arranged on a side of the first wedge mirror group away from the second wedge mirror group, for compressing the target light beam.

3. The optical fiber nutation coupling device based on double wedge scanning according to claim 1, characterized in that: The first wedge mirror group and the second wedge mirror group are arranged facing each other.

4. The optical fiber nutation coupling device based on double wedge scanning according to claim 1, characterized in that: The first wedge lens group and the second wedge lens group both include: an optical wedge, a wedge lens barrel and a bearing; The first optical wedge is an optical wedge of the first wedge lens group, and the first optical wedge is installed in the wedge lens barrel of the first wedge lens group; The second optical wedge is an optical wedge of the second wedge lens group, and the second optical wedge is installed in the wedge lens barrel of the second wedge lens group; A bearing is sleeved on the outer side of the wedge lens barrel, and the bearing is installed in the housing. The wedge lens barrel is rotatably installed in the housing through the bearing.

5. The optical fiber nutation coupling device based on double wedge scanning according to claim 4, characterized in that: It also includes a motor, which is mounted on the outside of the wedge lens barrel and is used to drive the wedge lens barrel to rotate, thereby driving the optical wedge to rotate.

6. The optical fiber nutation coupling device based on double wedge scanning according to claim 5, characterized in that: It also includes an encoder, which is sleeved on the outside of the wedge lens barrel and is electrically connected to the motor to detect the rotation direction and rotation angle of the optical wedge.

7. The optical fiber nutation coupling device based on double wedge scanning according to claim 1, characterized in that: The optical fiber is a single-mode optical fiber.

8. The optical fiber nutation coupling device based on double wedge scanning according to claim 1, characterized in that: It also includes an actuator, which is axially movably mounted on one end of the housing close to the coupling mirror assembly, the receiving end of the optical fiber is mounted on the actuator, and the actuator is used to adjust the distance between the coupling mirror assembly and the receiving end of the optical fiber.

9. A control method for a fiber nutation coupling device based on double wedge scanning according to any one of claims 1 to 8, characterized in that: A method for controlling a fiber nutation coupling device based on dual wedge scanning when the fiber position is unknown or lost, comprising: Step 1, controlling the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction, performing a rapid and comprehensive scan, detecting whether an optical signal is coupled into the optical fiber, and controlling the first optical wedge and the second optical wedge to rotate according to the detection information feedback until it is detected that an optical signal is coupled into the optical fiber; Step 2: roughly estimate the position of the optical fiber receiving end according to the feedback information of the optical signal coupled into the optical fiber, and then control the first optical wedge and the second optical wedge to rotate in opposite directions and / or in the same direction at a small angle according to the position of the optical fiber receiving end, perform preliminary scanning, detect the optical output coupling efficiency of the target light beam coupled into the optical fiber, and control the rotation of the first optical wedge and the second optical wedge according to the detection information feedback until it is detected that the optical output coupling efficiency of the target light beam coupled into the optical fiber reaches 10%; Step 3: According to the feedback information of the light output coupling efficiency of the target light beam coupled into the optical fiber, the rotation steps of the first optical wedge and the second optical wedge are adjusted, and the first optical wedge and the second optical wedge are controlled to rotate in opposite directions and / or in the same direction at a small angle to perform precise scanning, and the light output coupling efficiency of the target light beam coupled into the optical fiber is detected. According to the feedback information, the first optical wedge and the second optical wedge are controlled to rotate until the light output coupling efficiency of the target light beam coupled into the optical fiber reaches a maximum. Step 4: Start communication, monitor the stability of the feedback optical signal in real time, suspend communication when the optical output coupling efficiency of the target light beam coupled into the optical fiber is less than 45%, and repeat step 3 to ensure the stability of communication.

10. The control method of the optical fiber nutation coupling device based on double wedge scanning according to claim 9, characterized in that: Also included is a control method for an optical fiber nutation coupling device based on double wedge scanning when importing optical fiber position reference information, comprising: Step 1', obtaining optical fiber position reference information; according to the obtained optical fiber position reference information, controlling the first optical wedge and the second optical wedge to rotate in opposite and / or same directions at a small angle, performing preliminary scanning, detecting the optical output coupling efficiency of the target light beam coupled into the optical fiber, and controlling the first optical wedge and the second optical wedge to rotate according to the feedback information until it is detected that the optical output coupling efficiency of the target light beam coupled into the optical fiber reaches 10%; After the step 1' is completed, the steps 3 and 4 are executed.

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