Reflection-type double-channel optical fiber rotary connector

Abstract

The invention relates to an optical fiber rotary connector, in particular to a reflection type double-channel optical fiber rotary connector, and aims to overcome the defects that in the prior art, an optical fiber rotary connector is high in machining difficulty and alignment requirement, and the reliability and the service life of a system are affected by arrangement of a transmission mechanism and a driving motor. The reflective dual-channel optical fiber rotary connector comprises a stator end and a rotor end, wherein the rotor end comprises a first collimating and beam expanding assembly for transmitting a central optical signal and a second collimating and beam expanding assembly for transmitting an off-axis optical signal; the stator end comprises a meniscus lens, a light path deflection assembly, a self-focusing lens, a beam shrinking assembly and a gradient refractive index lens; the meniscus lens and the first collimating and beam expanding assembly are coaxially arranged, and the convex surface faces the first collimating and beam expanding assembly; the light path deflection assembly and the self-focusing lens are sequentially arranged along a central light signal transmitted by the meniscus lens; the beam shrinking assembly and the gradient refractive index lens are sequentially arranged along the off-axis optical signal transmitted by the meniscus lens.

Description

Technical Field

[0001] The invention relates to an optical fiber rotary connector, in particular to a reflective dual-channel optical fiber rotary connector. Background Art

[0002] Fiber optic rotary connectors are also called fiber optic slip rings, fiber optic rotary joints, optical hinges, etc. Their function is to solve the problem of optical signal transmission between relatively rotating parts and ensure that the transmission of optical signals is not interrupted due to rotation. Fiber optic rotary connectors have the advantages of contactless transmission, anti-electromagnetic interference, large transmission bandwidth and high transmission rate. According to the number of channels, they can be divided into single-channel, dual-channel and multi-channel. Dual-channel and multi-channel fiber optic rotary connectors have large transmission signal capacity and can realize two-way transmission, but they are large in size and relatively complex in structure. They are mainly used in wind power generation, photoelectric theodolites, medical CT, aerospace equipment and other fields

[0003] Compared with the single-channel fiber optic rotary connector, the dual-channel fiber optic rotary connector has many significant advantages. It can transmit two optical signals, so that the transmission capacity can be expanded, which can meet the needs of multi-type or large-scale data transmission in high-definition video surveillance systems and avoid transmission bottlenecks; it can realize two-way transmission, such as sending and receiving information at the same time in industrial automation control systems, which enhances communication flexibility and efficiency; it can provide two independent transmission paths, and when one channel fails, the other can still work, which can effectively ensure the normal operation of the system in fields such as aerospace and communications that require extremely high reliability; it can also reduce the number of connectors and equipment size, optimize system layout, and have outstanding advantages in miniaturized or portable devices; and the internal dual channels are relatively independent and have strong anti-interference capabilities, which can ensure stable signal quality and accurate transmission in complex electromagnetic environments.

[0004] The Chinese patent with publication number CN108680997A discloses a multi-channel hollow optical fiber rotary connector, which uses the light beam reflection on the inner conical surface of the hollow annular cone to realize the transmission of three groups of signals. The invention uses a shading tube to block light, and at the same time can effectively solve the problem that the central axis cannot transmit signals due to occupation. It has a simple structure, good stability, and high assembly precision, and can realize dynamic, off-axis, and circumferential transmission of signals. However, this method has high requirements for the processing and coating of the hollow annular cone, resulting in increased manufacturing difficulty and cost; and the overall alignment and coupling of the system is difficult, which easily increases the transmission loss of the optical fiber signal.

[0005] The Chinese patent with publication number CN118838009A discloses a multi-channel optical fiber rotary connector, which uses a drive motor set between the stator and the rotor to drive the differential mechanism to realize the self-driven rotation of the Dove prism. The invention is internally configured with a drive motor to control the rotation in accordance with the needs of the output end, without the need for complex external drive, avoiding damage to the optical fiber and improving the convenience of use; only adding a micro drive motor, the overall size growth is limited, the appearance is simple, and the space required for the drive is reduced, which can be applied to areas with small installation or use space; avoiding the limitation of the external drive on the range of optical fiber activities, reducing the difficulty of structural design and installation, expanding the scope of application, and improving the stability and accuracy of light transmission. However, the need to set up a transmission mechanism and a drive motor leads to a low working life and reliability of the optical fiber rotary connector, which is difficult to meet the requirements of long-life use in space.

[0006] The Chinese patent with publication number CN113866900A discloses a multi-channel optical fiber rotary connector, which is based on the setting of the dove prism. By optimizing the structural design, it avoids the introduction of the adjustment system and eliminates the adjustment link of the optical fiber collimator. By coordinating the positioning planes, the adjustment link of the dove prism posture is reduced, and different inner diameter sections are set to prevent the dove prism from being damaged and make it easier to fix, reduce assembly adjustment errors, and improve assembly efficiency. However, this method still requires precise fine-tuning. At the same time, there is a transmission structure, which has a great impact on the reliability and service life of the transmission system.

[0007] The Chinese patent with publication number CN117555083A discloses a super-multi-channel optical fiber rotary connector, which realizes the design of super-multi-channel optical fiber rotary connector without changing the aperture of light by staggering the concave and convex in the same layer or arranging the inner and outer layers, and solves the problem of large data transmission volume in the optical fiber communication system. Although this method adds more signal transmission channels, it puts forward higher requirements on the assembly of the dove prism and the alignment of the optical fiber, and it is difficult to ensure the consistency of the optical fiber alignment, which makes the transmission loss of some optical fibers larger. Summary of the invention

[0008] The purpose of the present invention is to solve the shortcomings of the prior art optical fiber rotary connector, such as high processing difficulty and high alignment requirements, and the provision of a transmission mechanism and a drive motor that affects the reliability and service life of the system, and to provide a reflective dual-channel optical fiber rotary connector.

[0009] To achieve the above objectives, the technical solutions provided by the present invention are as follows:

[0010] A reflective dual-channel optical fiber rotary connector, comprising a stator end and a rotor end, wherein the rotor end comprises a rotor end cover and a first collimating beam expanding assembly and a second collimating beam expanding assembly arranged on the rotor end cover, the input ends of the first collimating beam expanding assembly and the second collimating beam expanding assembly are respectively connected to an input optical fiber, the central axis of the first collimating beam expanding assembly coincides with the central axis of the rotor end cover, and the central axis of the second collimating beam expanding assembly is parallel to the central axis of the rotor end cover; the stator end comprises a stator sleeve and an optical module arranged in the stator sleeve, the rotor end cover is coaxially nested at one end of the stator sleeve and is rotatably connected thereto; the optical module comprises a meniscus lens, an optical path deflection assembly, a self-focusing lens, a beam reducing assembly, a self-focusing lens ... An assembly and a gradient refractive index lens; the meniscus lens is arranged in one end close to the stator sleeve, coaxially arranged with the first collimating beam expanding assembly, and the convex surface faces the first collimating beam expanding assembly; it is defined that the optical signal input by the first collimating beam expanding assembly is a central optical signal, and the optical signal input by the second collimating beam expanding assembly is an off-axis optical signal; the optical path deflection assembly and the self-focusing lens are arranged in sequence along the central optical signal transmitted by the meniscus lens, the optical path deflection assembly is used to reflect the central optical signal transmitted by the meniscus lens to the self-focusing lens, and an output optical fiber is arranged at the output end of the self-focusing lens; the beam reduction assembly and the gradient refractive index lens are arranged in sequence along the off-axis optical signal transmitted by the meniscus lens, and another output optical fiber is arranged at the output end of the gradient refractive index lens.

[0011] Furthermore, the stator end also includes a stator end cover arranged at the other end of the stator sleeve, and two mounting holes are opened on the stator end cover, and the gradient refractive index lens and the self-focusing lens are respectively arranged in the corresponding mounting holes.

[0012] Furthermore, a mounting sleeve is provided at one end of the stator end cover close to the stator sleeve corresponding to the gradient refractive index lens, and the beam reduction assembly is provided in the mounting sleeve.

[0013] Furthermore, it also includes a lens frame, a gasket and a pressure ring. The meniscus lens is fixedly connected to the inner wall of the stator sleeve through the lens frame. The gasket is arranged between the lens frame and the inner wall of the stator sleeve. The pressure ring is arranged at a position of the meniscus lens close to one end of the stator sleeve.

[0014] Further, the optical path deflection assembly comprises a first plane reflector and a second plane reflector which are sequentially arranged along the optical path;

[0015] The first plane reflector is fixedly connected to the inner side wall of the stator sleeve through the first support member, the mirror frame and the pressure ring;

[0016] The second plane reflecting mirror is fixedly connected to the inner side wall of the stator sleeve through a second supporting member, a mirror frame and a pressing ring.

[0017] Further, the central axis of the gradient refractive index lens coincides with the central axis of the stator sleeve;

[0018] The first collimating beam expanding component and the second collimating beam expanding component are configured as self-focusing lenses;

[0019] The beam reduction assembly includes an aspheric lens and a concave lens sequentially arranged along the optical path. The aspheric lens is used to fold the off-axis optical signal transmitted by the meniscus lens to the concave lens and reduce the beam. The concave lens is used to reduce the received off-axis optical signal.

[0020] Further, the input optical fiber is a single-mode optical fiber;

[0021] The output optical fiber is configured as a TEC optical fiber;

[0022] The rotor end cover is connected to the stator sleeve via a bearing.

[0023] Furthermore, the optical path deflection component is configured as a prism, the prism is located between the meniscus lens and the self-focusing lens, and at the same time, is located between the meniscus lens and the beam reduction component, and is used to reflect the central light signal transmitted by the meniscus lens to the self-focusing lens, and at the same time reflect the off-axis light signal transmitted by the meniscus lens to the beam reduction component;

[0024] The shrinkage assembly is configured as a Cassegrain shrinkage system.

[0025] Beneficial effects of the present invention:

[0026] 1. The present invention considers the dual-channel signal transmission method in a rotating state from a system level, adopts a method without a transmission mechanism, has a simple overall structure, and the transmission channels are independent of each other and do not interfere with each other. Compared with the method using a Dove prism in the prior art, each channel of the present invention can respectively realize the assembly adjustment of the corresponding optical lens and structure without being affected by other channels, so that the transmission efficiency and reliability are relatively high.

[0027] 2. The off-axis collimated light beam of the present invention is reduced by the reduction assembly at the stator end and then transmitted to the gradient refractive index lens and coupled to the optical fiber. There is no obstruction in the transmission process of the off-axis collimated light beam. The three lenses are all at the stator end, and only the beam collimator is at the rotor end, which greatly reduces the influence of the lens group installation error on the beam pointing during the rotation process.

[0028] 3. The present invention adopts an all-optical link design, which is not susceptible to electromagnetic interference and has higher reliability. At the same time, it has the advantages of optical fiber signal transmission. Compared with conductive slip rings, it solves the problems of low bandwidth, small capacity, slow rate, low life and reliability of signal transmission between rotating motion mechanisms.

[0029] 4. The present invention is a reflective dual-channel optical fiber signal transmission system, which uses a double reflector to change the beam pointing of the central collimated light beam, only changing the direction of the beam but not the size of the beam, thereby achieving high-efficiency coupling at the receiving end; the use of a double reflector simplifies the central channel signal transmission method, reduces the difficulty of system installation and adjustment, and improves the signal transmission efficiency. At the same time, the structure will not interfere with the off-axis channel, thereby ensuring the signal transmission quality.

[0030] 5. The present invention simplifies the overall structure of the signal transmission system, reduces the complexity of the system, and does not set up any transmission mechanism. There is no friction and wear physical process such as mechanical contact in the transmission process. It has the advantages of high reliability, long life and easy maintenance. It is particularly suitable for fields with strict requirements on weight, stability and environmental adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0032] Description of reference numerals:

[0033] 1-input optical fiber, 2-bearing, 3-first collimating and expanding assembly, 4-stator sleeve, 5-mirror frame, 6-gasket, 7-pressure ring, 8-second support, 9-second plane reflector, 10-aspheric lens, 11-mounting sleeve, 12-stator end cover, 13-rotor end cover, 14-meniscus lens, 15-first support, 16-first plane reflector, 17-gradient refractive index lens, 18-concave lens, 19-self-focusing lens, 20-output optical fiber, 21-second collimating and expanding assembly. DETAILED DESCRIPTION

[0034] Embodiment 1

[0035] The present invention discloses a reflective dual-channel optical fiber rotary connector, comprising a stator end and a rotor end, such as Figure 1 As shown, the rotor end includes a rotor end cover 13 and a first collimating beam expanding assembly 3 and a second collimating beam expanding assembly 21 arranged on the rotor end cover 13. The input ends of the first collimating beam expanding assembly 3 and the second collimating beam expanding assembly 21 are respectively connected to an input optical fiber 1. The central axis of the first collimating beam expanding assembly 3 coincides with the central axis of the rotor end cover 13, and the central axis of the second collimating beam expanding assembly 21 is parallel to the central axis of the rotor end cover 13. In this embodiment, the first collimating beam expanding assembly 3 and the second collimating beam expanding assembly 21 are configured as self-focusing lenses, or other optical fiber collimators such as C-lens and aspherical mirror groups, and the input optical fiber 1 is a single-mode optical fiber.

[0036] The stator end includes a stator sleeve 4 and an optical module arranged in the stator sleeve 4. The rotor end cover 13 is coaxially nested at one end of the stator sleeve 4 and is rotatably connected to it through a bearing 2; the optical module includes a meniscus lens 14, an optical path deflection assembly, a self-focusing lens 19, a beam reduction assembly and a gradient refractive index lens 17.

[0037] The meniscus lens 14 is arranged in one end close to the stator sleeve 4, and is fixedly connected to the inner wall of the stator sleeve 4 through the lens holder 5. A gasket 6 is arranged between the lens holder 5 and the inner wall of the stator sleeve 4. A pressing ring 7 is arranged at the position of the meniscus lens 14 close to one end of the stator sleeve 4 to fix the position of the meniscus lens 14. The meniscus lens 14 is coaxially arranged with the first collimating and expanding assembly 3, and the convex surface faces the first collimating and expanding assembly 3. By definition, the optical signal input by the first collimating and expanding assembly 3 is a central optical signal, and the optical signal input by the second collimating and expanding assembly 21 is an off-axis optical signal.

[0038] The optical path deflection assembly and the self-focusing lens 19 are sequentially arranged along the central light signal transmitted by the meniscus lens 14. The optical path deflection assembly is used to reflect the central light signal transmitted by the meniscus lens 14 to the self-focusing lens 19. An output optical fiber 20 is arranged at the output end of the self-focusing lens 19. The optical path deflection assembly includes a first plane reflector 16 and a second plane reflector 9 sequentially arranged along the optical path; the first plane reflector 16 is fixedly connected to the inner wall of the stator sleeve 4 through the first support member 15, a mirror frame 5 is arranged between the first support member 15 and the inner wall of the stator sleeve 4, and a pressure ring 7 is arranged at a position of the first support member 15 close to one end of the stator sleeve 4 to fix the axial position of the first support member 15; similarly, the second plane reflector 9 is fixedly connected to the inner wall of the stator sleeve 4 through the second support member 8, the mirror frame 5, and the pressure ring 7.

[0039] The beam reduction assembly and the gradient refractive index lens 17 are sequentially arranged along the off-axis optical signal transmitted by the meniscus lens 14, and another output optical fiber 20 is arranged at the output end of the gradient refractive index lens 17, and the output optical fiber 20 is arranged as a TEC optical fiber. The beam reduction assembly includes an aspheric lens 10 and a concave lens 18 sequentially arranged along the optical path, and the aspheric lens 10 is used to bend the off-axis optical signal transmitted by the meniscus lens 14 to the concave lens 18 and reduce the beam, and the concave lens 18 is used to reduce the received off-axis optical signal. In other embodiments of the present invention, the beam reduction assembly can also be set as a Cassegrain beam reduction system or other reversing optical systems; the gradient refractive index lens 17 can be replaced by an aspheric lens, a C-lens or other lenses.

[0040] In order to facilitate the fixing of the reduction assembly, the gradient refractive index lens 17 and the self-focusing lens 19, a stator end cover 12 is also provided at the other end of the stator sleeve 4. Two mounting holes are provided on the stator end cover 12. The gradient refractive index lens 17 and the self-focusing lens 19 are respectively provided in the corresponding mounting holes. The central axis of the gradient refractive index lens 17 coincides with the central axis of the stator sleeve 4. A mounting sleeve 11 is provided at one end of the stator end cover 12 close to the stator sleeve 4 corresponding to the gradient refractive index lens 17, and the reduction assembly is provided in the mounting sleeve 11.

[0041] A reflective dual-channel optical fiber rotary connector of the present invention has a central channel and an off-axis channel. In the central channel, the central optical signal is transmitted to the first collimating and expanding assembly 3 via a single-mode optical fiber. After expansion and collimation, it passes through a meniscus lens 14 and is incident on a first plane reflector 16. After reflection to a second plane reflector 9, especially after reflection, it is emitted in parallel to a self-focusing lens 19 and coupled to a corresponding output optical fiber 20. In the off-axis channel, the off-axis optical signal is transmitted to the second collimating and expanding assembly 21 via a single-mode optical fiber. After expansion and collimation, it passes through a meniscus lens 14, an aspheric lens 10, and a concave lens 18 in sequence, and then is transmitted to a gradient refractive index lens 17 after being reduced in size, and then coupled to a corresponding output optical fiber 20.

[0042] The present invention adopts a beam reduction system and a gradient refractive index lens to achieve high-efficiency coupling of off-axis light beams. By optimizing and adjusting the beam reduction ratio, gradient refractive index focal length and aperture, and adopting TEC fiber as the output fiber 20, the beam coupling efficiency can be further improved.

[0043] Embodiment 2

[0044] The only difference between this embodiment and the first embodiment is that the optical path deflection component is configured as a prism, and the prism is located between the meniscus lens 14 and the self-focusing lens 19, and at the same time, between the meniscus lens 14 and the shrinking component, and is used to reflect the central light signal transmitted by the meniscus lens 14 to the self-focusing lens 19, and at the same time reflect the off-axis light signal transmitted by the meniscus lens 14 to the shrinking component.

Claims

1. A reflective dual-channel optical fiber rotary connector, comprising a stator end and a rotor end, characterized in that: The rotor end comprises a rotor end cover (13) and a first collimating beam expanding assembly (3) and a second collimating beam expanding assembly (21) arranged on the rotor end cover (13); the input ends of the first collimating beam expanding assembly (3) and the second collimating beam expanding assembly (21) are respectively connected to an input optical fiber (1); the central axis of the first collimating beam expanding assembly (3) coincides with the central axis of the rotor end cover (13); and the central axis of the second collimating beam expanding assembly (21) is parallel to the central axis of the rotor end cover (13); The stator end comprises a stator sleeve (4) and an optical module arranged in the stator sleeve (4); the rotor end cover (13) is coaxially nested at one end of the stator sleeve (4) and is rotatably connected thereto; the optical module comprises a meniscus lens (14), an optical path deflection assembly, a self-focusing lens (19), a beam reduction assembly, and a gradient refractive index lens (17); The meniscus lens (14) is arranged in one end close to the stator sleeve (4), coaxially arranged with the first collimating beam expanding component (3), with the convex surface facing the first collimating beam expanding component (3); it is defined that the optical signal input by the first collimating beam expanding component (3) is a central optical signal, and the optical signal input by the second collimating beam expanding component (21) is an off-axis optical signal; The optical path deflection component and the self-focusing lens (19) are arranged in sequence along the central light signal transmitted by the meniscus lens (14); the optical path deflection component is used to reflect the central light signal transmitted by the meniscus lens (14) to the self-focusing lens (19); an output optical fiber (20) is arranged at the output end of the self-focusing lens (19); The beam reduction assembly and the gradient refractive index lens (17) are arranged in sequence along the off-axis optical signal transmitted by the meniscus lens (14), and another output optical fiber (20) is arranged at the output end of the gradient refractive index lens (17).

2. According to claim 1, a reflective dual-channel optical fiber rotary connector, characterized in that: The stator end also includes a stator end cover (12) arranged at the other end of the stator sleeve (4), and two mounting holes are provided on the stator end cover (12), and the gradient refractive index lens (17) and the self-focusing lens (19) are respectively arranged in the corresponding mounting holes.

3. According to claim 2, a reflective dual-channel optical fiber rotary connector, characterized in that: A mounting sleeve (11) is arranged at one end of the stator end cover (12) close to the stator sleeve (4) and corresponding to the gradient refractive index lens (17), and the beam reduction assembly is arranged in the mounting sleeve (11).

4. A reflective dual-channel optical fiber rotary connector according to any one of claims 1 to 3, characterized in that: The invention also comprises a lens frame (5), a washer (6) and a pressure ring (7); the meniscus lens (14) is fixedly connected to the inner wall of the stator sleeve (4) through the lens frame (5); the washer (6) is arranged between the lens frame (5) and the inner wall of the stator sleeve (4); and the pressure ring (7) is arranged at a position of the meniscus lens (14) close to one end of the stator sleeve (4).

5. A reflective dual-channel optical fiber rotary connector according to claim 4, characterized in that: The optical path deflection assembly comprises a first plane reflector (16) and a second plane reflector (9) which are sequentially arranged along the optical path; The first plane reflector (16) is fixedly connected to the inner side wall of the stator sleeve (4) through the first support member (15), the mirror frame (5) and the pressure ring (7); The second plane reflector (9) is fixedly connected to the inner side wall of the stator sleeve (4) via a second support member (8), a mirror frame (5) and a pressure ring (7).

6. The reflective dual-channel optical fiber rotary connector according to claim 5, characterized in that: The central axis of the gradient refractive index lens (17) coincides with the central axis of the stator sleeve (4); The first collimating beam expanding component (3) and the second collimating beam expanding component (21) are configured as self-focusing lenses; The beam reduction assembly comprises an aspheric lens (10) and a concave lens (18) which are sequentially arranged along an optical path. The aspheric lens (10) is used to deflect the off-axis optical signal transmitted by the meniscus lens (14) to the concave lens (18) and reduce the beam. The concave lens (18) is used to reduce the received off-axis optical signal.

7. A reflective dual-channel optical fiber rotary connector according to claim 6, characterized in that: The input optical fiber (1) is a single-mode optical fiber; The output optical fiber (20) is configured as a TEC optical fiber; The rotor end cover (13) is connected to the stator sleeve (4) via a bearing (2).

8. The reflective dual-channel optical fiber rotary connector according to claim 4, characterized in that: The optical path deflection component is configured as a prism, the prism being located between the meniscus lens (14) and the self-focusing lens (19), and also between the meniscus lens (14) and the beam reduction component, and being used for reflecting the central light signal transmitted by the meniscus lens (14) to the self-focusing lens (19), and reflecting the off-axis light signal transmitted by the meniscus lens (14) to the beam reduction component; The shrinkage assembly is configured as a Cassegrain shrinkage system.

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