Preparation method of short-beat-length optical fiber fixing block assembly

Abstract

The invention relates to a preparation method of a short-beat-length optical fiber fixing block assembly. The preparation method comprises the following steps: processing a long-strip fixing block for fixing a short-beat-length optical fiber, grinding and polishing a plane, bonded with a Y waveguide, of the long-strip fixing block to form an angle, cutting the whole row of long-strip fixing blocks with the ground angle into a plurality of single fixing blocks, and forming a fixed shaft groove in each single fixing block; the optical fiber is fixed in the fixed shaft groove of the single fixed block, the head of the optical fiber extends out for a certain length, and the optical fiber in the fixed shaft groove is bonded with the fixed block; wrapping the short-beat long bare fiber extending out of the fixed block with liquid wax, and heating and curing; and the fixing block assembly with the short-beat-length optical fiber is installed on the grinding and polishing machine, when the fixing block assembly descends to the position of the head of the optical fiber and makes contact with the grinding disc, the fixing block assembly stops, and the short-beat-length bare fiber extending out of the fixing block is ground till the short-beat-length bare fiber is flush with the end face of the fixing block. The assembly is used for coupling and bonding an optical fiber ring and a Y waveguide device, coupling points in an optical path of the optical fiber gyroscope are reduced, welding loss is reduced, and the purpose of improving the optical path assembling efficiency of the optical fiber gyroscope is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical engineering and relates to a method for preparing a short-beat-length optical fiber fixing block assembly. Background Art

[0002] Y waveguide and fiber ring are important optical devices in the optical path of fiber optic gyroscope, such as Figure 8 As shown in the figure, when assembling the optical path of the current fiber optic gyroscope, the two output ends of the Y waveguide need to be polarization-maintainingly welded with the two output ends of the fiber ring respectively, which not only affects the assembly efficiency of the fiber optic gyroscope optical path, but also introduces welding loss to the optical path of the fiber optic gyroscope. At the same time, the welding point will also reduce the reliability of the optical path. The requirements of high precision, short production cycle and high quality requirements for aerospace products are facing unprecedented challenges and opportunities. The way to remove the welding point is to directly couple the two output ends of the fiber ring with the two output ends of the Y waveguide, but the optical fiber used for the current Y waveguide is a special optical fiber for the Y waveguide, which is very different from the optical fiber used for the fiber ring. The optical fiber used for the fiber ring is a short-beat-long optical fiber, which is almost 100% cracked after grinding.

[0003] The existing solution for grinding the optical fiber fixing block assembly for Y-waveguide is: firstly bond the optical fiber to the whole row of fixing block assemblies, with 18 optical fibers bonded in each row, and then remove the optical fiber extending out of the end face of the fixing block. After removal, the whole row of optical fibers is clamped and ground together with the fixing block. After grinding, no axial cracks will be generated on the end face of the optical fiber. However, this solution is not suitable for the short-beat-length optical fiber used in the optical fiber ring. Therefore, a short-beat-length optical fiber fixing block assembly preparation solution needs to be redesigned to solve the cracking problem of the short-beat-length optical fiber used in the optical fiber ring after grinding, so as to realize the direct coupling of the two output ends of the optical fiber ring with the two output ends of the Y-waveguide. Summary of the invention

[0004] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art, to propose a method for preparing a short-beat-length optical fiber fixing block assembly, and to solve the problem of cracking of short-beat-length optical fibers used in optical fiber rings after grinding.

[0005] The solution to the technical problem of the present invention is: a method for preparing a short-beat long optical fiber fixing block assembly, comprising the following steps:

[0006] Processing a long fixed block for fixing short-beat long optical fiber, wherein the surface of the long fixed block has a plurality of fixed axis grooves, first grinding the plane of the long fixed block for bonding with the Y waveguide to an angle in a row, and then cutting the long fixed block with an angle in the row into a plurality of single fixed blocks, each of which has a fixed axis groove;

[0007] Strip off the coating layer of the short-length optical fiber head, fix the optical fiber in the fixed axis groove of a single fixing block, extend the optical fiber head for a certain length, and bond the optical fiber in the fixed axis groove to the fixing block;

[0008] Wrap all the short-beat long bare fibers extending out of the fixed block with liquid wax and heat and solidify them;

[0009] Install the fixed block assembly with short-beat length optical fiber on the grinding and polishing machine, and monitor the position of the optical fiber head with a microscope. When the micrometer head fixture carrying the optical fiber fixed block assembly descends to the point where the optical fiber head contacts the grinding disk, it stops, and the grinding and polishing machine is turned on to grind off the short-beat length bare fiber protruding from the fixed block until it is flush with the end face of the fixed block, ensuring that the angle of the optical fiber end face is consistent with and flush with the angle of the fixed block.

[0010] Furthermore, the long strip fixing block is a trapezoidal structure, and the fixed axis groove is processed in the plane where the short side or the long side of the long strip fixing block is located. The two fixing blocks with different fixed axis groove processing positions are respectively connected to the two output ends of the short-beat long optical fiber.

[0011] Furthermore, the side of the long fixed block at which the polishing angle is ground corresponds to the plane where the hypotenuse of the trapezoidal structure is located, and the polishing angle is 15°±0.5°.

[0012] Furthermore, viewed from the side where the long fixed block is ground and thrown out at an angle, the distance between the fixed axis groove processed on the plane where the short side is located and the right edge of the plane is 1 / 3 of the plane width, and the distance between the fixed axis groove processed on the plane where the long side is located and the left edge of the plane is 1 / 3 of the plane width.

[0013] Furthermore, the spacing between two adjacent fixed axis grooves on the long strip fixing block is 1.5 mm ± 0.1 mm, and the cutting scale of the long strip fixing block is 1.5 mm ± 0.1 mm.

[0014] Furthermore, after the coating layer at the optical fiber head is stripped off, the bare fiber length is controlled between 1.5 mm and 1.8 mm.

[0015] Furthermore, the protruding length of the optical fiber head is 0.2mm-0.3mm.

[0016] Furthermore, the optical fiber in the fixed axis groove is bonded to the fixed block using UV glue.

[0017] Furthermore, before starting the grinding and polishing machine, the fixed block assembly is rotated 15°±0.5°.

[0018] Further, when the micrometer head fixture carrying the optical fiber fixing block assembly descends to the position where the optical fiber head contacts the grinding disk, it stops, and the grinding and polishing machine is turned on to grind off the short-beat long bare fiber extending out of the fixing block, as follows:

[0019] Before the grinder and polisher is turned on, the distance between the micrometer head fixture carrying the optical fiber fixing block assembly and the grinding disc of the grinder and polisher is 10cm-15cm, and then the up and down adjustment knobs on the micrometer head fixture carrying the optical fiber fixing block assembly are adjusted to lower the fixture. When the optical fiber at the head of the optical fiber fixing block assembly just contacts the grinding disc, the fixture stops descending. At this time, the micrometer value on the micrometer head is cleared to zero, and the micrometer head is used for fine adjustment to make the optical fiber fixing block assembly continue to descend, thereby applying pressure to the optical fiber head. When the micrometer value shows 0.01mm±0.001mm, the fixture stops descending and the grinder is turned on for grinding. During the process of grinding out the angle, the micrometer head is continuously lowered, and the maximum value of the micrometer does not exceed 0.02mm, so as to control the pressure on the optical fiber at the head of the optical fiber fixing block assembly until the end face of the optical fiber is flush with the end face of the fixing block, and the grinding is terminated.

[0020] The beneficial effects of the present invention compared with the prior art are:

[0021] (1) The present invention can accurately control the force applied to the short-beat-length optical fiber during grinding, thereby ensuring that no axial cracks are generated in the optical fiber after grinding;

[0022] (2) The present invention can adjust the grinding angle at will during grinding to ensure that the angle of the optical fiber is consistent with the angle of the fixed block;

[0023] (3) After the completion of the present invention, the two welding points during the optical path assembly of the fiber optic gyroscope can be reduced, thereby reducing the welding loss and shortening the optical path assembly time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of a whole row of fixed block assemblies according to an embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of a whole row of fixed block assemblies installed on a grinding fixture according to an embodiment of the present invention;

[0026] Figure 3 It is a schematic diagram of the end face grinding throw angle of the entire row of fixed block components;

[0027] Figure 4 is a schematic diagram of a whole row of fixed block components cut into individual components according to an embodiment of the present invention;

[0028] Figure 5 is a schematic diagram of bonding an optical fiber to a fixing block assembly according to an embodiment of the present invention;

[0029] Figure 6 This is a finished picture of the polished optical fiber head in an embodiment of the present invention;

[0030] Figure 7 This is a flow chart of a method for preparing a short-beat length optical fiber fixing block assembly of the present invention;

[0031] Figure 8 It is a schematic diagram of polarization-maintaining welding of the output end of a Y-waveguide and the output end of an optical fiber ring in the background technology;

[0032] In the figure: 1-a whole row of fixed block assemblies, 2-fixed axis grooves of a whole row of fixed blocks, 3-installation positions of a whole row of fixed blocks, 4-end faces after grinding, 5-fixed axis grooves of a single fixed block, 6-liquid wax wrapping position, 7-angle of optical fiber end faces. DETAILED DESCRIPTION

[0033] like Figure 7 As shown, a method for preparing a short-beat length optical fiber fixing block assembly proposed by the present invention comprises the following steps:

[0034] S1. Process a long strip fixing block for fixing short-beat long optical fiber, wherein the surface of the long strip fixing block has a plurality of fixed axis grooves, and grind the plane of the long strip fixing block for bonding with the Y waveguide to an angle in a row, and then cut the long strip fixing block with an angle in a row into a plurality of single fixing blocks, each of which has a fixed axis groove.

[0035] Among them, the long strip fixing block is a trapezoidal structure, and the fixed axis groove is processed on the plane where the short side of the long strip fixing block is located (upper surface) or the plane where the long side is located (lower surface), and the two fixing blocks with different fixed axis groove processing positions are respectively connected to the two output ends of the short-beat long optical fiber.

[0036] The side of the long fixed block with a grinding and polishing angle corresponds to the plane where the hypotenuse of the trapezoidal structure is located, and the grinding and polishing angle is 15°±0.5°.

[0037] From the side of the long fixed block grinding throw angle, the distance between the fixed axis groove processed on the plane where the short side is located and the right edge of the plane is 1 / 3 of the plane width, and the distance between the fixed axis groove processed on the plane where the long side is located and the left edge of the plane is 1 / 3 of the plane width;

[0038] The spacing between two adjacent fixed axis grooves on the long strip fixing block is 1.5 mm ± 0.1 mm, and the cutting scale of the long strip fixing block is 1.5 mm ± 0.1 mm.

[0039] S2. Strip off the coating layer of the short-length optical fiber head, fix the optical fiber in the fixed axis groove of a single fixing block, extend the optical fiber head for a certain length, and bond the optical fiber in the fixed axis groove to the fixing block with UV glue.

[0040] Among them, after the coating layer at the optical fiber head is stripped off, the bare fiber length is controlled between 1.5mm-1.8mm.

[0041] The protruding length of the optical fiber head is preferably 0.2mm-0.3mm.

[0042] S3, wrapping all the short-beat long bare fibers extending out of the fixed block with liquid wax, and heating and curing them;

[0043] S4. Install the fixed block assembly with the short-length optical fiber on the grinding and polishing machine. Monitor the position of the optical fiber head with a microscope. When the micrometer head fixture carrying the optical fiber fixed block assembly descends to make the optical fiber head contact the grinding disk, it stops. Turn on the grinding and polishing machine to grind off the short-length bare fiber protruding from the fixed block until it is flush with the end face of the fixed block, ensuring that the angle of the optical fiber end face is consistent with the angle of the fixed block and is flush.

[0044] Among them, after stopping the descent and before starting the grinder and polisher, the fixed block assembly is rotated 15°±0.5°.

[0045] The process of controlling the descent of the micrometer head fixture and grinding the short-shot long bare fiber protruding from the fixed block is as follows: before the grinding and polishing machine is turned on, the micrometer head fixture carrying the optical fiber fixed block assembly is 10cm-15cm away from the grinding disc of the grinding and polishing machine, and then the up and down adjustment knobs on the micrometer head fixture carrying the optical fiber fixed block assembly are adjusted to lower the fixture. When the optical fiber at the head of the optical fiber fixed block assembly just contacts the grinding disc, the descent is stopped; at this time, the micrometer value on the micrometer head is cleared to zero, and the micrometer head is used for fine adjustment to make the optical fiber fixed block assembly continue to descend, thereby applying pressure to the optical fiber head. When the micrometer value shows 0.01mm±0.001mm, the descent is stopped, and the grinding machine is turned on for grinding. During the process of grinding out the angle, the micrometer head is continuously lowered, and the maximum value of the micrometer value does not exceed 0.02mm, so as to control the pressure on the optical fiber at the head of the optical fiber fixed block assembly, and the grinding is terminated until the end face of the optical fiber is flush with the end face of the fixed block.

[0046] The optical fiber output ends on one side of the two fixed block components that are ground at an angle are respectively coupled and bonded to the two output ends of the Y waveguide.

[0047] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0048] Example 1

[0049] like Figure 1 The figure shows a schematic diagram of a whole row of fixed block components 1 designed in the present invention. It can be seen from the figure that there are multiple fixed axis grooves 2 on the upper surface of the whole row of fixed block components. The spacing between the fixed axis grooves is 1.5 mm. The fixed axis grooves are prepared by etching on a three-inch wafer. The size of a single fixed block component is controlled by dicing. The size after dicing is 30 mm*2.1 mm*1.5 mm.

[0050] The whole row of cut fixed block components is installed on the grinding fixture, such as Figure 2 As shown, the entire row of fixed block components is in position 3, the number of each grinding is 12, the rear end face angle after grinding is 15°, and the end face 4 after grinding is as shown in FIG. Figure 3 shown.

[0051] Will Figure 3The whole row of fixed block components with angles ground are pasted on the dicing machine for dicing. The dicing division is 1.5mm. The dicing effect is shown in the figure below. Figure 4 As shown, there is a fixed axis groove 5 on the upper surface of each fixed block.

[0052] Strip off 3mm of the coating layer at the head of the short-shot long optical fiber, and then use a cutting knife to cut off a part of the bare fiber to ensure that the bare fiber length is controlled between 1.5mm-1.8mm, and then fix the short-shot long optical fiber in the fixed axis groove of a single fixed block with a graduation of 1.5mm. The optical fiber head extends out for a length of about 0.2mm-0.3mm. The optical fiber in the fixed axis groove is bonded to the fixed block with UV glue. After the optical fiber is bonded to the fixed block, the bare fiber extending out of the fixed block is all wrapped with a liquid wax. After being completely wrapped, it is cured at high temperature. The curing temperature range is 80℃±1℃. The liquid wax wrapping position 6 is as follows Figure 5 shown.

[0053] Install the fixed block assembly with short-beat-length optical fiber on a small grinding and polishing machine that can accurately control pressure. Monitor the position of the optical fiber head with a microscope. Stop when it drops to contact with the grinding disk. Then rotate the fixed block assembly 15° for grinding. Grind off the short-beat-length bare fiber protruding from the fixed block until it is flush with the end face of the fixed block. Ensure that the optical fiber end face angle 7 is consistent with the angle of the fixed block and is flush. The effect after grinding is as follows: Figure 6 shown.

[0054] In summary, the present invention provides a method for preparing a short-beat length optical fiber fixing block assembly, in which an angle is ground on the end face of the fixing block, the short-beat length optical fiber and the fixing block are axially aligned, the optical fiber head is extended for a certain length, and finally the extended optical fiber is ground off to prepare the short-beat length optical fiber fixing block assembly. This assembly is used for coupling and bonding the optical fiber ring with the Y-waveguide device, thereby reducing the coupling points in the optical path of the optical fiber gyroscope, reducing the fusion loss, and achieving the purpose of improving the assembly efficiency of the optical path of the optical fiber gyroscope.

[0055] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0056] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A method for preparing a short-beat length optical fiber fixing block assembly, characterized in that: The following steps are involved: Processing a long fixed block for fixing short-beat long optical fiber, wherein the surface of the long fixed block has a plurality of fixed axis grooves, first grinding the plane of the long fixed block for bonding with the Y waveguide to an angle in a row, and then cutting the long fixed block with an angle in the row into a plurality of single fixed blocks, each of which has a fixed axis groove; Strip off the coating layer of the short-length optical fiber head, fix the optical fiber in the fixed axis groove of a single fixing block, extend the optical fiber head for a certain length, and bond the optical fiber in the fixed axis groove to the fixing block; Wrap all the short-beat long bare fibers extending out of the fixed block with liquid wax and heat and solidify them; Install the fixed block assembly with short-beat length optical fiber on the grinding and polishing machine, and monitor the position of the optical fiber head with a microscope. When the micrometer head fixture carrying the optical fiber fixed block assembly descends to the point where the optical fiber head contacts the grinding disk, it stops, and the grinding and polishing machine is turned on to grind off the short-beat length bare fiber protruding from the fixed block until it is flush with the end face of the fixed block, ensuring that the angle of the optical fiber end face is consistent with and flush with the angle of the fixed block.

2. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: The long strip fixing block is a trapezoidal structure, and the fixed axis groove is processed in the plane where the short side of the long strip fixing block is located or the plane where the long side is located. The two fixing blocks with different fixed axis groove processing positions are respectively connected to the two output ends of the short-beat long optical fiber.

3. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 2, characterized in that: The side of the long fixed block with a grinding and polishing angle corresponds to the plane where the hypotenuse of the trapezoidal structure is located, and the grinding and polishing angle is 15°±0.5°.

4. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 3, characterized in that: Viewed from the side where the long fixed block is ground at an angle, the distance between the fixed axis groove processed on the plane where the short side is located and the right edge of the plane is 1 / 3 of the plane width, and the distance between the fixed axis groove processed on the plane where the long side is located and the left edge of the plane is 1 / 3 of the plane width.

5. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: The spacing between two adjacent fixed axis grooves on the long strip fixing block is 1.5 mm ± 0.1 mm, and the cutting scale of the long strip fixing block is 1.5 mm ± 0.1 mm.

6. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: After the coating layer at the optical fiber head is stripped off, the bare fiber length is controlled between 1.5mm-1.8mm.

7. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: The protruding length of the optical fiber head is 0.2mm-0.3mm.

8. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: The optical fiber in the fixed axis groove is bonded to the fixed block with UV glue.

9. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: Before starting the grinder-polisher, rotate the fixed block assembly 15°±0.5°.

10. The method for preparing a short-beat length optical fiber fixing block assembly according to claim 1, characterized in that: When the micrometer head fixture carrying the optical fiber fixing block assembly is lowered to the position where the optical fiber head contacts the grinding disc, it stops, and the polishing machine is turned on to grind off the short-beat long bare fiber extending out of the fixing block, as follows: Before the grinder and polisher is turned on, the distance between the micrometer head fixture carrying the optical fiber fixing block assembly and the grinding disc of the grinder and polisher is 10cm-15cm, and then the up and down adjustment knobs on the micrometer head fixture carrying the optical fiber fixing block assembly are adjusted to lower the fixture. When the optical fiber at the head of the optical fiber fixing block assembly just contacts the grinding disc, the fixture stops descending. At this time, the micrometer value on the micrometer head is cleared to zero, and the micrometer head is used for fine adjustment to make the optical fiber fixing block assembly continue to descend, thereby applying pressure to the optical fiber head. When the micrometer value shows 0.01mm±0.001mm, the fixture stops descending and the grinder is turned on for grinding. During the process of grinding out the angle, the micrometer head is continuously lowered, and the maximum value of the micrometer does not exceed 0.02mm, so as to control the pressure on the optical fiber at the head of the optical fiber fixing block assembly until the end face of the optical fiber is flush with the end face of the fixing block, and the grinding is terminated.

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