A high-directivity collimated light adapter and its assembly and debugging method

Abstract

The present invention discloses a highly directional collimated light adapter capable of realizing an integral sealing structure of an outer sleeve, having a small deformation amount and good reliability, and an assembly and debugging method thereof. The highly directional collimated light adapter includes an outer sleeve and a pneumatic suction tooling; a ceramic ring, a ceramic ferrule, an isolator core and a lens are arranged in the outer sleeve; the assembly and debugging method includes the steps of: S1, first fixing the ceramic ferrule in the ceramic ring, and then fixing the ceramic ring and the isolator core in the outer sleeve; S2, fixing the outer sleeve on a V-groove fixture, and fixing the pneumatic suction tooling on a three-dimensional adjustment frame; S3, debugging the position of the lens by adjusting the X, Y, and Z axes of the three-dimensional adjustment frame, and gluing on the contact surface between the lens and the outer sleeve; S4, after the lens is glued and thermally cured or ultraviolet cured, stop sucking air and remove the pneumatic suction tooling. By adopting the highly directional collimated light adapter and the assembly and debugging method thereof, the spot size and spot characteristics can be precisely controlled, and the coaxiality is good.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber communication, and in particular to a highly directive parallel optical adapter and an assembly and debugging method thereof. Background Art

[0002] It is well-known that optical communication is the core technology of information networks. An optical module realizes the function of optical-electric conversion. The industrial chain includes chips (electric / optical), devices (passive / active), and finished modules. Among them: the chip technology has a high technical barrier and a value proportion of 30%-70%. High-end products are monopolized by foreign countries; there are a wide variety of optical devices, and the value of active devices is relatively concentrated, with global specialized collaborative competition; the iteration speed of finished modules has accelerated significantly, and the strength of China has risen. 100G has become the mainstream in 2017, and 400G has been widely applied in 2019 and will become the core product with value growth.

[0003] An optical isolator is connected between a laser and a transmission optical fiber, which can effectively suppress the reflected light generated from the distal end face of the optical fiber, the interface of the optical fiber connector, etc. in the line from returning to the laser, thereby ensuring the stable working state of the laser and reducing the noise caused by the reflected light in the system. This is more important for high-speed optical fiber communication coherent optical fiber communication systems. Its function is to prevent the adverse effects of backward transmitted light generated due to various reasons in the optical path on the light source and the optical path system. Optical isolators play an important role in optical fiber communication, optical information processing systems, optical fiber sensing, and precision optical measurement systems.

[0004] With the increasing popularity of the application of optical fiber networks, especially the rapid implementation of the current 5G network, and point-to-point data transmission, especially the large-scale deployment of 5G midhaul and fronthaul nodes, the market demand for single-fiber bidirectional components with narrow wavelength intervals is also increasing.

[0005] Currently, for high-end active products, such as 4*25G, 4*50G, 4*100G, 50G bidirectional transceivers, parallel light coupling is required for transceivers with the same wavelength or adjacent wavelengths.

[0006] However, the light beam emitted by the existing ordinary optical head is a divergent light beam, which is not suitable for high-end active products that require parallel light coupling.

[0007] Currently, there is an existing type of parallel optical head, such as Figure 1As shown in the figure, it includes a first outer sleeve 11, a ceramic ring 2, a ceramic ferrule 3, a second outer sleeve 12, an isolator core 4 and a lens 5. The assembly method is to first fix the ceramic ferrule 3 in the ceramic ring 2, and then fix the ceramic ring 2 in the first outer sleeve 11; fix the isolator core 4 and the lens 5 in the second outer sleeve 12. When the optical performance is adjusted to the best design, the second outer sleeve 12 and the first outer sleeve 11 are laser welded together. For the parallel optical head with this structure, the outer sleeve is not integral, but two outer sleeves are welded together. During the welding process, it is prone to deformation, the coaxial effect is not good, the sealing effect is not good, and the reliability is not good. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a high-directivity parallel optical adapter that can achieve an integral sealing structure of the outer sleeve, has a small deformation amount, and good reliability.

[0009] The technical solution adopted by the present invention to solve its technical problems is: a high-directivity parallel optical adapter, including an outer sleeve; a ceramic ring, a ceramic ferrule, an isolator core and a lens are arranged inside the outer sleeve; one end of the ceramic ferrule is located inside the ceramic ring; the isolator core is located at the other end of the ceramic ferrule; the lens is located at one end of the isolator core; one end of the outer sleeve is provided with a pneumatic suction tooling for adjusting the position of the lens.

[0010] Further, the pneumatic suction tooling includes a hollow glass tube and a hollow metal tube; one end of the hollow glass tube is provided with a lens contact end face matching the surface of the lens; one end of the hollow glass tube matches the inner cavity of one end of the outer sleeve; the lens contact end face contacts the lens; the other end of the hollow glass tube is communicated with and sealed to one end of the hollow metal tube; the central axis of the hollow glass tube is perpendicular to the central axis of the hollow metal tube;

[0011] A light passing hole is provided on the hollow metal tube opposite to the end face of the hollow glass tube, and a window piece 8 for sealing the light passing hole is provided on the hollow metal tube.

[0012] Preferably, the outer sleeve adopts an integral sealing structure.

[0013] The present invention also discloses an assembly and debugging method for the high-directivity parallel optical adapter described above, using a V-groove fixture and a three-dimensional adjustment frame; and including the following steps:

[0014] S1, first fix the ceramic ferrule in the ceramic ring, and then fix the ceramic ring and the isolator core in the outer sleeve;

[0015] S2, fix the outer sleeve on the V-groove fixture, and fix the pneumatic suction tooling on a three-dimensional adjustment frame; the pneumatic suction tooling sucks the lens through suction, and places the lens inside the outer sleeve;

[0016] S3. Adjust the position of the lens by adjusting the X, Y, and Z axes of the three-dimensional adjustment frame. When the optical performance is adjusted to the best design, apply glue on the contact surface between the lens and the outer sleeve.

[0017] S4. After the glue on the lens is cured by heat or ultraviolet light, stop the air suction and remove the air suction tooling. Remove the high-directivity collimated light adapter from the fixture, and the debugging and assembly are completed.

[0018] Further, in step S3, place the pre-fixed high-directivity collimated light adapter in the V-groove surface of the V-groove fixture, and press the high-directivity collimated light adapter tightly. Rotate the high-directivity collimated light adapter one circle, and use a spot meter to measure the trajectory of the spot at the L working distance. Then, the center of the trajectory circle and the radius r of the trajectory circle can be determined on the spot meter.

[0019] According to tanθ = r / L, then θ = arctan(r / L) can be calculated, and it can be judged whether θ meets the design index requirements. Therefore, a specific area can be set in the spot meter, with the center of the measured trajectory circle as the center and r0 as the radius. Since tanθ = r / L and r = Ltanθ, when θ = θ0 (θ0 is the size required by the design), r0 = Ltanθ0. Therefore, at the L distance, a specific area of the trajectory circle with r0 as the radius is set on the spot meter.

[0020] When adjusting the lens, by adjusting the X-axis and Y-axis of the three-dimensional adjustment frame, adjust the position of the spot center to within the specific area. At this time, the off-axis angle θ meets the requirements.

[0021] Wherein, θ is the off-axis angle, L is the distance from the lens to the spot machine, and r is the radius of the trajectory circle of the center of the spot 10 when the high-directivity collimated light adapter is rotated one circle on the V-groove at the L distance. Among them, L is determined by the design index.

[0022] The beneficial effects of the present invention are: For a high-directivity collimated light adapter described in the present invention, since an air suction tooling is used to realize the positioning of the lens, the deformation amount is small, the coaxiality is good, and the reliability is high.

[0023] Secondly, the high-directivity collimated light adapter takes the mechanical axis center of the outer sleeve as the reference, has high directivity, and the off-axis angle of the collimated light is very small. The spot size and spot characteristics of the high-directivity collimated light adapter can be precisely controlled. The high-directivity collimated light adapter is internally provided with an isolator core to realize the function of the isolator. An optical device made of the high-directivity collimated light adapter does not need to be additionally provided with an isolator, and the volume becomes smaller. Description of the Drawings

[0024] Figure 1 is a structural schematic diagram of a collimated light head in the prior art;

[0025] Figure 2 is a schematic three-dimensional structure diagram of an embodiment of a high-directivity collimated light adapter in the present invention;

[0026] Figure 3 is a schematic cross-sectional structure diagram of an embodiment of a high-directivity collimated light adapter in the present invention;

[0027] Figure 4 is a Gaussian beam diagram in the present invention;

[0028] Figure 5 is a schematic structure diagram of a high-directivity collimated light adapter clamped in a V-groove in the present invention;

[0029] Figure 6 is a schematic diagram of the off-axis angle debugging principle of a high-directivity collimated light adapter in the present invention;

[0030] Reference numerals in the figures: 1 - outer sleeve, 2 - ceramic ring, 3 - ceramic ferrule, 4 - isolator core, 5 - lens, 6 - hollow glass tube, 61 - lens contact end face, 7 - hollow metal tube, 8 - window piece, 9 - V-groove fixture, 91 - V-groove face, 10 - light spot. Detailed implementation manners

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] As Figures 1 to 6 shown, a high-directivity collimated light adapter according to the present invention includes an outer sleeve 1; a ceramic ring 2, a ceramic ferrule 3, an isolator core 4, and a lens 5 are arranged inside the outer sleeve 1; one end of the ceramic ferrule 3 is located inside the ceramic ring 2; the isolator core 4 is located at the other end of the ceramic ferrule 3; the lens 5 is located at one end of the isolator core 4;

[0033] An air suction tooling for adjusting the position of the lens 5 is arranged at one end of the outer sleeve 1. The air suction tooling includes a hollow glass tube 6 and a hollow metal tube 7;

[0034] A lens contact end face 61 matching the surface of the lens 5 is arranged at one end of the hollow glass tube 6; one end of the hollow glass tube 6 matches the inner cavity at one end of the outer sleeve 1; that is, one end of the hollow glass tube 6 can be in contact with or not in contact with the outer sleeve 1; one end of the hollow glass tube 6 can be inserted into one end of the outer sleeve 1; but the two are not connected; and the lens contact end face 61 is in contact with the lens 5; the other end of the hollow glass tube 6 is communicated with and hermetically connected to one end of the hollow metal tube 7; the center line of the hollow glass tube 6 is perpendicular to the center line of the hollow metal tube 7;

[0035] A light passing hole a is arranged on the hollow metal tube 7 opposite to the end face of one end of the hollow glass tube 6, and a window piece 8 for sealing the light passing hole a is arranged on the hollow metal tube 7.

[0036] Specifically, the ceramic ring 2 is used to hold the above-mentioned ceramic ferrule 3, and the outer sleeve 1 is used to hold the above-mentioned ceramic ring 2, isolator core 4 and lens 5. The hollow glass tube 6 is processed by the same optical process as the lens 5, and its end face is polished into a concave surface, while the lens is a convex surface. The curvature radius of the lens contact end face 61 of the air suction tooling is the same as that of the lens 5. The hollow metal tube 7 has a light through hole at the position a directly opposite to the hollow glass tube 6, and a window piece 8 is attached.

[0037] In order to improve the sealing performance, preferably, the outer sleeve 1 adopts an integral sealing structure.

[0038] The present invention also provides an assembly and debugging method for the above-mentioned highly directive parallel light adapter, which uses a V-groove fixture 9 and a three-dimensional adjustment frame; and includes the following steps:

[0039] S1, first fix the ceramic ferrule 3 in the ceramic ring, and then fix the ceramic ring 2 and the isolator core 4 in the outer sleeve 1;

[0040] S2, fix the outer sleeve 1 on the V-groove fixture 9, and fix the air suction tooling on a three-dimensional adjustment frame; the air suction tooling sucks the lens 5 through suction and places the lens 5 inside the outer sleeve 1;

[0041] S3, adjust the position of the lens 5 by adjusting the X, Y, and Z axes of the three-dimensional adjustment frame. When the optical performance is adjusted to the best design, glue is applied to the contact surface between the lens 5 and the outer sleeve 1;

[0042] S4, after the glue is thermally cured or ultraviolet cured on the lens, stop suction and remove the air suction tooling; remove the highly directive parallel light adapter from the fixture, and the debugging and assembly are completed.

[0043] Specifically, first fix the ceramic ferrule 3 in the ceramic ring 2, and then fix the ceramic ring 2 and the isolator core 4 in the outer sleeve 1. Fix the outer sleeve 1 assembled with the ceramic ferrule 3 and the isolator core 4 on the V-groove fixture 9, and fix the air suction tooling on a three-dimensional adjustment frame. When the hollow metal tube 7 of the air suction tooling sucks air, the lens contact end face 61 of the air suction tooling sucks the lens 5 and places the lens 5 inside the outer sleeve 1 for debugging.

[0044] Please refer to Figure 6 , by adjusting the Z axis of the three-dimensional adjustment frame to adjust the position of the lens, the size of the light spot can be adjusted. At the distance L (the distance from the lens 5 to the light spot machine) determined by the design index, the light spot is adjusted to the size of the design index. As Figure 4 shown, the light spot characteristics of the Gaussian beam determine the size of the light spot at a specific distance. By adjusting the X axis and Y axis of the three-dimensional adjustment frame to adjust the position of the lens, the position of the light spot center can be adjusted to enter a specific area of the light spot machine (such as Figure 6inside the trajectory circle with a radius of r = r0 as shown, that is, the magnitude of the off-axis angle meets the design specifications. When the optical performance is debugged to the best design, glue is applied on the contact surface between the lens 5 and the outer sleeve 1. After heat curing or ultraviolet curing the lens 5 with glue, stop the air suction and remove the air suction tooling. Remove the high-directivity collimated light adapter from the V-groove fixture 9, and the assembly is completed.

[0045] Specifically, referring to Figure 5 and Figure 6 , debug the off-axis angle. In step S3, place the pre-fixed high-directivity collimated light adapter in the V-groove surface 91 of the V-groove fixture 9 and press the high-directivity collimated light adapter tightly; rotate the high-directivity collimated light adapter one circle, and use a spot meter to measure the trajectory of the spot at the L working distance, then the center of the trajectory circle and the radius r of the trajectory circle can be determined on the spot meter;

[0046] According to tanθ = r / L, then calculate θ = arctan(r / L), and it can be judged whether θ meets the design specification requirements; a specific area can be set in the spot meter, with the center of the above-measured trajectory circle as the center and r0 as the radius. Since tanθ = r / L and r = Ltanθ, when θ = θ0, θ0 is the required magnitude in the design and r0 = Ltanθ0; therefore, at the L distance, a specific area of the trajectory circle with a radius of r0 is set on the spot meter;

[0047] When adjusting the lens, by adjusting the X-axis and Y-axis of the three-dimensional adjustment frame, adjust the position of the spot center to within the specific area, and at this time the off-axis angle θ meets the requirements;

[0048] Among them, θ is the off-axis angle, L is the distance from the lens 5 to the spot meter, and r is the radius of the trajectory circle of the center of the spot 10 when the high-directivity collimated light adapter rotates one circle on the V-groove at the L distance; where L is determined by the design specifications.

[0049] Preferably, in the embodiment of the present invention, the lens can be hidden inside the outer sleeve or exposed outside the outer sleeve.

[0050] Preferably, the air suction tooling is not limited to the structure in this embodiment, as long as it is an air suction tooling that clamps the lens by the method of air suction on the lens to accurately adjust the three-dimensional position of the lens, it belongs to the patent scope of the present invention.

Claims

1. A high-directivity parallel light adapter, characterized in that: It includes an outer sleeve (1); a ceramic ring (2), a ceramic ferrule (3), an isolator core (4) and a lens (5) are arranged inside the outer sleeve (1); one end of the ceramic ferrule (3) is located inside the ceramic ring (2); the isolator core (4) is located at the other end of the ceramic ferrule (3); the lens (5) is located at one end of the isolator core (4). One end of the outer sleeve (1) is provided with a pneumatic suction tooling for adjusting the position of the lens (5); the pneumatic suction tooling includes a hollow glass tube (6) and a hollow metal tube (7). One end of the hollow glass tube (6) is provided with a lens contact end face (61) matching the surface of the lens (5); one end of the hollow glass tube (6) matches the inner cavity of one end of the outer sleeve (1); the lens contact end face (61) contacts the lens (5); the lens contact end face (61) is a concave surface, and the lens (5) is a convex surface; the radius of curvature of the lens contact end face (61) is the same as that of the lens (5); the other end of the hollow glass tube (6) is communicated with and hermetically connected to one end of the hollow metal tube (7); the center line of the hollow glass tube (6) is perpendicular to the center line of the hollow metal tube (7). A light passing hole (a) is arranged on the hollow metal tube (7) directly opposite to the end face of one end of the hollow glass tube (6), and a window piece (8) for sealing the light passing hole (a) is arranged on the hollow metal tube (7). The outer sleeve (1) adopts an integral sealing structure.

2. The assembly and debugging method of the highly directional collimated light adapter according to claim 1, characterized in that A V-groove fixture (9) and a three-dimensional adjustment frame are adopted; and the following steps are included: S1, first fix the ceramic ferrule (3) in the ceramic ring, and then fix the ceramic ring (2) and the isolator core (4) in the outer sleeve (1). S2, fix the outer sleeve (1) on the V-groove fixture (9), and fix the pneumatic suction tooling on a three-dimensional adjustment frame; the pneumatic suction tooling sucks the lens (5) by suction and places the lens (5) inside the outer sleeve (1). S3, adjust the position of the lens (5) by adjusting the X, Y, and Z axes of the three-dimensional adjustment frame. When the optical performance is adjusted to the best design, glue is applied to the contact surface between the lens (5) and the outer sleeve (1). S4, after the glue is thermally cured or ultraviolet cured on the lens, stop suction and remove the pneumatic suction tooling; remove the high-directivity collimated light adapter from the fixture, and the debugging and assembly are completed.

3. The assembly and debugging method of the high-directivity collimated light adapter according to claim 2, wherein: In step S3, place the pre-fixed high-directivity collimated light adapter in the V-groove surface (91) of the V-groove fixture (9), and press the high-directivity collimated light adapter; rotate the high-directivity collimated light adapter one circle, and measure the trajectory of the light spot with a light spot meter at the L working distance, then the center of the trajectory circle and the radius r of the trajectory circle can be determined on the light spot meter. According to tanθ = r / L, θ = arctan(r / L) can be calculated to determine whether θ meets the design index requirements; a specific area can be set in the spot meter, with the center of the trajectory circle measured above as the center and r0 as the radius. Since tanθ = r / L and r = Ltanθ, when θ = θ0 (where θ0 is the size required by the design), r0 = Ltanθ0; therefore, at a distance of L, a specific area of a trajectory circle with a radius of r0 is set on the spot meter. When adjusting the lens, by adjusting the X-axis and Y-axis of the three-dimensional adjustment frame, the position of the spot center is adjusted to within the specific area, and at this time the off-axis angle θ meets the requirements. Among them, θ is the off-axis angle, L is the distance from the lens (5) to the spot machine, and r is the radius of the trajectory circle of the center of the spot (10) when the highly directional parallel light adapter rotates one circle on the V-groove at a distance of L; L is determined by the design index.

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