CN105806328A - Shielding structure capable of improving properties of optical fiber loop of optical fiber gyroscope - Google Patents

Abstract

The invention discloses a shielding structure for improving the performance of an optical fiber gyro optical fiber ring. It includes a base and a shield fixed on the base. The base includes a base, a loading board and a multi-layer partition laid between the base and the loading board. Between the base and the partition, the partition and the loading A shielding plate is provided between the plates and between two adjacent partitions. The shielding cover includes multiple layers of shells nested in sequence. A shielding shell is provided between the adjacent two shells. The base and the shielding cover are fixed by screws. . The invention can effectively reduce the influence of external environmental factors on the optical fiber ring of the optical fiber gyroscope, thereby reducing the noise introduced in the output signal of the optical fiber gyroscope by external environment fluctuations, improving the measurement accuracy and environmental adaptability of the optical fiber gyroscope, and expanding the application range of the optical fiber gyroscope.

Description

A Shielding Structure for Improving the Performance of Fiber Optic Gyro Fiber Ring

technical field

The invention relates to an optical fiber sensing technology and a shielding structure, in particular to a shielding structure for improving the performance of an optical fiber gyroscope fiber ring.

Background technique

Fiber optic gyroscopes are widely used in aerospace, missile guidance and other fields due to their characteristics of all solid state, no moving parts, and low cost. A typical fiber optic gyro system includes a light source, a light source coupler, an integrated Y waveguide, a polarization control device, a fiber optic ring, a photodetector, an analog-to-digital converter, a digital-to-analog converter, and a digital processor. The light emitted by the light source is divided into two parts by the light source coupler, one part of the light enters the integrated Y waveguide, and the other part of the light is absorbed by the dead end of the light source coupler. The light entering the Y waveguide is divided into two beams, clockwise and counterclockwise, and enters the fiber ring from the two pigtails of the fiber ring. When the gyro rotates at a certain angular velocity around its sensitive axis relative to the inertial system, a phase difference proportional to the rotational angular velocity is generated between the two beams of light transmitted in the opposite direction in the fiber ring due to the Segneck effect. After passing through the optical fiber ring, the two beams of reverse transmission are combined into one beam of light by the integrated Y waveguide, and interfere. The photodetector detects the interference light intensity, and converts the light intensity signal into a digital signal through an analog-to-digital converter, which is received by a digital processor. The digital processor solves the light intensity signal to obtain the rotational angular velocity of the fiber optic gyroscope around its sensitive axis relative to the inertial system, and sends a feedback signal through the digital-to-analog converter to control the integrated Y waveguide to realize the closed-loop control of the fiber optic gyroscope.

As the main component and sensitive unit of the fiber optic gyroscope, the performance of the fiber optic ring determines the measurement accuracy and application range of the fiber optic gyroscope. The optical signal transmitted in the optical fiber ring is easily disturbed by external environmental factors, such as vibration, temperature and sound waves, which will cause changes in the phase of the optical signal in the optical fiber, and finally reflected as noise in the output signal of the fiber optic gyroscope after solving. In low-precision fiber optic gyroscopes, the influence of the environment on the fiber optic ring of the fiber optic gyroscope can be ignored. But in the high-precision fiber optic gyroscope, the impact of environmental factors on the fiber optic ring of the fiber optic gyroscope cannot be ignored. The shielding of environmental factors is not considered in the traditional fiber optic ring packaging structure, which makes the traditional fiber ring packaging unusable in high-precision fiber optic gyroscopes.

The fiber optic interferometer proposed in the patent CN102901521 has moving parts in the vibration and sound insulation packaging structure, which cannot be used in the fiber optic gyroscope.

Contents of the invention

In order to solve the problems existing in the background technology, the present invention proposes a shielding structure and an assembly method for improving the performance of the fiber optic ring of the fiber optic gyroscope.

The technical scheme that the present invention adopts is as follows:

The invention includes a base and a shielding cover fixedly mounted on the base, the base includes a base, a loading board and a multi-layer partition laid between the base and the loading board, between the base and the partition, between the partition and the A shielding plate is provided between the loading plates and between two adjacent partitions. The shielding cover includes multiple layers of shells nested in sequence. A shielding shell is provided between the adjacent two shells. The base and the shielding cover pass through Screw fixed.

The base of the present invention adopts a multi-layer stacking structure, including a first partition and a second partition respectively located at the upper and lower positions from the base to the loading plate, and the contact surface between the first partition and the base is provided with The first shielding plate, the contact surface between the first partition and the second partition is provided with a second shielding plate, the contact surface between the second partition and the loading plate is provided with a third shielding plate,

The four corners of the inner bottom surface of the base are provided with four base bosses with increasing heights, and each base boss is provided with a threaded hole, and each partition and the four corners of the loading plate are provided with a threaded hole. The four corners of the plate and the loading plate pass through their own threaded holes through a screw, and then pass through the lower partition and shielding plate in turn, and then are fixedly connected to the threaded holes of the base boss at the four corners of the base.

One side of the base is provided with a base opening for passing through the two pigtails of the optical fiber ring.

The shielding cover adopts a multi-layer nested structure, which is composed of a plurality of shell layers whose sizes gradually decrease.

The shielding cover includes a first shell layer, a second shell layer, a third shell layer and a fourth shell layer nested in sequence, and the contact surface between the first shell layer and the second shell layer is provided with a first shielding shell , the contact surface between the second shell layer and the third shell layer is provided with a second shielding shell, the contact surface between the third shell layer and the fourth shell layer is provided with a third shielding shell, and between adjacent shell layers The shell boss and the through-hole structure are nested with each other and fixedly connected with screw threaded holes.

The bottom peripheral surfaces of the first shell, the second shell and the third shell are all provided with flanges, and the bottom peripheral surfaces of the fourth shell are all provided with flat plates for cooperating with the inner bottom surface of the base, The flanges of the first shell, the second shell and the third shell, and the same side of the plate of the fourth shell are all provided with shell openings for passing through the two pigtails of the optical fiber ring, and the plate is provided with threaded holes, and the screws are in turn After passing through the threaded hole of the flat plate, the loading plate and the partitions of each layer, it is fixedly linked to the threaded hole of the base boss of the base.

When installed in place, the shell openings and the base openings of the shell layers are at the same side position and can be merged together.

The material of the base, partition, loading plate and shell layer is metal or engineering plastics. The metal material is aluminum, copper or similar materials. The engineering plastic is polytetrafluoroethylene or similar material.

Each shielding plate and each shielding shell are selected from heat insulation material, magnetic insulation material or sound insulation material, and the shielding materials of each layer are combined in any number and order of the above three materials.

The heat insulating material is glass wool or materials with similar properties. The magnetic isolation material is permalloy or materials with similar properties. The sound insulation material is sound insulation felt or similar material.

The realization principle of the present invention is: the fiber ring of the fiber optic gyroscope is placed in the shielding structure, and the two tail fibers of the fiber ring are led out through the opening on the shield cover and the base. The shielding structure is composed of a base and a shielding cover. The base is composed of a base, a multi-layer partition, a loading plate and a shielding material filled therebetween. The shielding case is composed of multiple nested shells and shielding material filled between every two shells. The shielding material can choose a single heat insulation material, magnetic insulation material, sound insulation material or fill the three kinds of shielding materials in any number of layers and in any order according to requirements. For example, the shielding plate in the base uses sound insulation felt, permalloy, and glass wool from bottom to top, and the shield shell in the shielding cover uses sound insulation felt, permalloy, and glass wool from outside to inside, respectively, which can achieve simultaneous heat shielding. , Magnetic and acoustic effects.

When filled with heat insulating material, it can block the influence of thermal radiation emitted by the circuit part on the fiber ring; when filled with magnetic isolation material, it can reduce the influence of the ambient magnetic field on the fiber ring; when filled with sound insulation material, it can reduce the fiber ring The intensity of the sound wave at the place, thereby reducing the influence of the ambient sound wave on the fiber optic ring. Taking the filled sound insulation material as an example, the external sound waves are reflected and absorbed on the shell structure, and the remaining sound waves that penetrate the shell are reflected and absorbed by the sound insulation material. The multilayer stacked structure and the multilayer nested structure are extremely Greatly enhanced the sound insulation effect. By changing the number of filling layers, the combination of types of shielding materials, and the different filling sequences of shielding materials, the requirements of different application environments for the performance of the fiber optic gyroscope fiber ring can be met.

The beneficial effects that the present invention has are:

The structure of the invention has the characteristics of simple structure, convenient processing, all solid state, no moving parts, and functions can be expanded according to requirements.

The shielding structure of the present invention can effectively reduce the influence of external environmental factors, including temperature, magnetic field and sound waves on the fiber optic gyroscope fiber ring, and overcome the inability of the existing fiber optic gyroscope fiber ring package to effectively shield the external temperature, magnetic field and sound waves from affecting the fiber optic gyroscope fiber ring. Insufficient impact.

The base of the present invention adopts a multi-layer stacking structure, and the shielding cover adopts a multi-layer nesting structure. Using the structure in the fiber optic gyroscope can effectively reduce the influence of external environmental factors on the fiber optic ring of the fiber optic gyroscope, thereby reducing external environmental fluctuations in the fiber optic gyroscope. The noise introduced in the output signal improves the measurement accuracy and environmental adaptability of the fiber optic gyroscope, and expands the application range of the fiber optic gyroscope.

And the present invention also has broad application prospects in other types of fiber optic interferometers, for example, in a Mach-Zehnder type interferometer, the reference arm fiber can be placed in the shielding structure, and the sensitive ring can be placed in the environment to be measured. By analyzing the interference signal of the interferometer, environmental factors such as temperature, magnetic field, and sound waves can be measured.

Description of drawings

Fig. 1 is the effect diagram after the structure of the present invention is completely installed.

Fig. 2 is an effect diagram of connecting the structural base and the shielding cover through screws in the present invention.

Fig. 3 is an assembly effect drawing of the base of the embodiment.

Fig. 4 is an assembly effect drawing of the shielding cover of the embodiment.

Fig. 5 is a structural cross-sectional view of the base stacking structure and shielding case nesting structure of the present invention.

Fig. 6 is a cross-sectional view of the opening structure of the base and the shielding case for passing two pigtails of the fiber ring according to the present invention.

Fig. 7 is a diagram showing the simulation analysis results of the shielding structure using Comsol software in the embodiment.

In the figure: shielding cover 11, screw 12, base 13, base 31, first shielding plate 32, first partition 33, second shielding plate 34, second partition 35, third shielding plate 36, loading plate 37, the first shell 41, the second shell 43, the third shell 45, the fourth shell 47, the first shielding shell 42, the second shielding shell 44, the third shielding shell 46, the base opening 315, the base Seat bosses 311, 312, 313, 314, threaded holes 331, 351, 371, shell openings 411, 431, 451, 471, shell bosses 412, 432, 452, flanges 414, 434, 454, threaded holes 413, 433,453, screw holes 435,455,475, flat plate 474, screw holes 476. The shielding cover passes through the opening B of the optical fiber, and the shielding structure passes through the opening C of the optical fiber.

detailed description

The present invention will be further described below in conjunction with drawings and embodiments.

As shown in Figures 1 and 2, the present invention comprises a base 13 and a shield 11 fixedly mounted on the base 13, the base 13 includes a base 31, a loading plate 37 and is laid between the base 31 and the loading plate 37 The multi-layer partitions 33, 35, between the base 31 and the partitions 33, 35, between the partitions 33, 35 and the loading plate 37, and between two adjacent partitions 33, 35 are provided with shielding plates 32, 34, 36, the shielding cover 11 includes multiple layers of shells 41, 43, 45, 47 nested in sequence, and the shielding shells 42, 44, 46 are arranged between two adjacent shells, the base 13 and the shielding cover 11 Fastened with screws 12.

As shown in Figure 3, the base of the present invention adopts a multi-layer stacking structure, including a first partition 33 and a second partition 35 respectively located at the upper and lower positions from the base 31 to the loading plate 37, the first partition 33 and the contact surface between the base 31 is provided with the first shielding plate 32, the contact surface between the first dividing plate 33 and the second dividing plate 35 is provided with the second shielding plate 34, the second dividing plate 35 and loading The contact surface between the plates 37 is provided with a third shielding plate 36, and the four corners of the inner bottom surface of the base 31 are all provided with four base bosses 311, 312, 313, 314 with successively increasing heights, each base boss 311 , 312, 313, and 314 are provided with threaded holes, specifically the following structural connections are adopted:

The four corners of the first partition 33 are provided with three through holes and a threaded hole 331, and the four corners of the first partition 33 pass through the threaded holes 331 and the first shielding plate 32 of itself through a screw 12 and are fixedly connected to the base 31 four corners of the base boss 311.

The four corners of the second dividing plate 35 are provided with two through holes and a threaded hole 351, and the four corners of the second dividing plate 35 pass through the threaded holes 351, the second shielding plate 34, and the first dividing plate successively by a screw 12. 33 and the first shielding plate 32 are fixedly connected to the base bosses 312 at the four corners of the base 31.

The four corners of the loading plate 37 are provided with a through hole and a threaded hole 371, and the four corners of the loading plate 37 pass through the threaded hole 371, the third shielding plate 36, the second dividing plate 35, the first screw 12, and so on. The second shielding plate 34 , the first partition plate 33 and the first shielding plate 32 are fixedly connected to the base bosses 313 at the four corners of the base 31 .

The threaded holes of the base boss 312 to which the screws 12 of the first partition 33 , the second partition 35 and the loading plate 37 are connected are different.

One side of the base 31 is provided with a base opening 315 for passing through the two pigtails of the fiber ring.

As shown in FIG. 4 , the shielding case 11 adopts a multi-layer nested structure, and is composed of a plurality of shell layers whose sizes gradually decrease. The shielding case 11 includes a first shell layer 41, a second shell layer 43, a third shell layer 45 and a fourth shell layer 47 nested in sequence, and the contact surface between the first shell layer 41 and the second shell layer 43 is provided with The contact surface between the first shielding shell 42, the second shell layer 43 and the third shell layer 45 is provided with the second shielding shell 44, and the contact surface between the third shell layer 45 and the fourth shell layer 47 is provided with the third shell layer. The shielding shell 46 is specifically connected by the following structure:

The first shell boss 412 is provided around the outer wall of the first shell layer 41, and the center of the first shell boss 412 is provided with a threaded hole 413. Cooperating through holes, threaded holes 435 are provided around the outer wall of the second shell 43, and the screws 12 pass through the threaded holes 435 of the second shell 43 and the through holes of the first shielding shell 42 in sequence, and then connected to the first shell 41 in the first shell boss 412 threaded hole 413.

A second shell boss 432 is provided around the outer wall of the second shell layer 43, and the second shell boss 432 is located between two adjacent first shell bosses 412 of the first shell layer 41. The second shell boss 432 The center is provided with a threaded hole 433, and the second shielding shell 44 is surrounded by a through hole for the insertion of the second shell boss 432, and the third shell 45 is provided with a threaded hole 455 around the outer wall, and the screws 12 pass through the After passing through the threaded hole 455 of the third shell 45 and the through hole of the second shielding shell 44 , it is connected to the threaded hole 433 of the second shell boss 432 of the second shell 43 .

A third shell boss 452 is provided around the outer wall of the third shell 45, and the third shell boss 452 is located between two adjacent second shell bosses 432 of the second shell 43. The third shell boss 452 The center is provided with a threaded hole 453, and the periphery of the third shielding shell 46 sidewall is provided with a through hole for the third shell boss 452 to embed and fit. After passing through the threaded hole 475 of the fourth shell 47 and the through hole of the third shielding shell 46 , it is connected to the threaded hole 453 of the third shell boss 452 of the third shell 45 .

The bottom peripheral surfaces of the first shell 41, the second shell 43 and the third shell 45 are provided with flanges 414, 434, 454, which are used to cooperate with the adjacent outer shells to seal the shielding material between the two. Between the shells; the bottom peripheral surface of the fourth shell 47 is provided with a flat plate 474 for cooperating with the inner bottom surface of the base 13, and is used to fix the base and the shield by screws; the first shell 41, the second shell The flanges 414, 434, 454 of the layer 43 and the third shell 45 and the same side of the flat plate 474 of the fourth shell 47 are provided with shell openings 411, 431, 451, 471 for passing through the two pigtails of the optical fiber ring, The flat plate 474 is provided with a threaded hole 476, and the screw 12 passes through the threaded hole 476 of the flat plate 474, the loading plate, and each layer of partitions in turn and is fixedly connected to the threaded hole of the base boss of the base 31.

As shown in FIG. 6 , when installed in place, the shell openings and the base openings of the various shell layers are at the same side position and can be merged together.

FIG. 5 is a longitudinal sectional view of the shielding structure. The base showing the structure has a multi-layer stacked structure, and the shield has a multi-layer nested structure.

FIG. 6 is a transverse cross-sectional view of the shielding structure. Shown are the openings in the base for the two pigtails that pass through the fiber optic ring, and the openings in each shell for the two pigtails that pass through the fiber optic ring. When installed in place, the base opening 315 on the base for passing the two pigtails of the optical fiber ring can be smoothly connected with the shell opening 315 on the shell for passing the two pigtails of the optical fiber ring, forming a shielding structure for passing the two pigtails of the optical fiber. pigtail channel.

The following is an example of a shielding structure with a base with 2 layers of partitions and a shielding cover with 4 layers of shells shown in Figures 3 and 4 to illustrate the installation steps of the shielding structure:

1) Coating the shielding material 42 on the outer surface of the cylindrical shell and the top outer surface of the innermost first shell 41 , the coating thickness is based on the height of the protrusion 412 outside the cylindrical shell of the first shell.

2) Embed the coated first shell in the second shell 43, so that the threaded hole 413 on the outer boss of the cylindrical shell of the first shell and the threaded hole 435 on the cylindrical shell of the second shell Align and secure with screws.

3) Coating the shielding material 44 on the outer surface of the cylindrical shell of the second shell 43 and the outer surface of the top, the coating thickness is based on the height of the protrusion 432 outside the cylindrical shell of the second shell.

4) Embedding the coated second shell in the third shell 45, so that the threaded hole 433 on the outer boss of the cylindrical shell of the second shell and the threaded hole 455 on the cylindrical shell of the third shell Align and secure with screws.

5) Coating the shielding material 46 on the outer surface of the cylindrical shell of the third shell 45 and the outer surface of the top, the coating thickness is based on the height of the protrusion 452 outside the cylindrical shell of the third shell.

6) Embed the coated third shell in the outermost fourth shell 47, so that the threaded hole 453 on the outer boss of the cylindrical shell of the third shell and the cylindrical shell of the fourth shell The threaded holes 475 are aligned and fixed with screws.

7) Coating the shielding material 32 in the base 31 , the coating thickness is based on the height of the shortest protrusion 311 . After coating, the surface of the coating material is flush with the shortest boss 311 . The coating material 32 can be selected from heat insulating material, magnetic insulating material or sound insulating material.

8) Fix the first partition 33 on the base 31 through the threaded hole 331 with screws.

9) Coating the shielding material 34 on the first partition 33, the coating thickness is based on the height of the shortest protrusion 312 visible at this time. After coating, the surface of the coating material is flush with the shortest protrusion 312 that is visible at this time. The coating material 34 can be selected from heat insulating material, magnetic insulating material or sound insulating material.

10) Fix the second partition plate 35 on the base 31 through the threaded hole 351 with screws.

11) Coating the shielding material 36 on the second partition 35, the coating thickness is based on the height of the shortest protrusion 313 visible at this time. After the coating is finished, the surface of the coating material is flush with the shortest protrusion 313 visible at this time. The coating material 36 can be selected from heat insulating material, magnetic insulating material or sound insulating material.

12) Fix the loading plate 37 on the base with screws through the threaded holes 371 .

13) The installed shielding cover 11 is fixed on the base 13 with screws 12, so that the opening 315 on the base for passing the two pigtails of the optical fiber ring and the opening 315 on the shielding cover for passing the two pigtails of the optical fiber ring The openings 61 are aligned.

The following two embodiments illustrate the use of the shielding structure:

1) In the fiber optic gyroscope, the sensitive fiber ring can be placed in the shielding structure, so that the fiber ring is isolated from the circuit part, and can also effectively reduce the influence of external environmental factors on the fiber optic ring of the fiber optic gyroscope, thereby reducing the noise introduced by the fluctuation of the external environment, Improve the measurement accuracy and environmental adaptability of fiber optic gyroscope.

2) In the Mach-Zehnder interferometer structure, the reference ring can be placed in the shielding structure, and the sensitive ring can be placed in the environment to be tested. By analyzing the interference signal of the interferometer, environmental factors such as temperature, magnetic field, and sound waves can be analyzed. Wait for the measurement.

As shown in FIG. 7 , taking shielding sound as an example, the embodiment of the present invention uses Comsol software to simulate and analyze the results of the shielding structure. The shielding material used in the simulation is glass wool. The abscissa is the sound frequency, the unit is kHz, and the ordinate is the sound attenuation effect of the structure, the unit is dB. It can be seen that the designed structure has a great attenuation effect on sound, and it can be seen that the technical effect of the result of the present invention is prominent.

Claims (8)

1. A shielding structure for improving the performance of the optical fiber gyroscope fiber ring, characterized in that: comprise a base (13) and a shielding cover (11) fixedly mounted on the base (13), the base (13) includes a base (31), The loading plate (37) and the multi-layer dividing plate (33,35) laid between the base (31) and the loading plate (37), between the base (31) and the dividing plate (33,35), Shielding plates (32, 34, 36) are arranged between the dividing plates (33, 35) and the loading plate (37) and between two adjacent dividing plates (33, 35), and the shielding cover (11) includes multiple Layers of shells (41, 43, 45, 47) nested in sequence, shielding shells (42, 44, 46) are arranged between adjacent two shells, and the base (13) and shielding cover (11) are connected by screws ( 12) Fixed. 2. A shielding structure for improving the performance of the fiber optic gyroscope fiber ring according to claim 1, characterized in that: it includes first spacers respectively located at the upper and lower positions from the base (31) to the carrier plate (37). Plate (33) and the second partition (35), the contact surface between the first partition (33) and the base (31) is provided with the first shielding plate (32), the first partition (33) and the second The contact surface between the two dividing plates (35) is provided with the second shielding plate (34), and the contacting surface between the second dividing plate (35) and the loading plate (37) is provided with the 3rd shielding plate (36), The four corners of the inner bottom surface of the base (31) are all provided with four base bosses (311, 312, 313, 314) whose heights are successively increasing, and each base boss (311, 312, 313, 314) is opened. Threaded holes are arranged, and the four jiaos of every dividing plate (33,35) and loading plate (37) are all provided with a threaded hole (331,351,371), the dividing plate (33,35) and loading plate (37) The four corners all pass through the threaded holes (331,351,371) of themselves by a screw (12) and then pass through the partition plate and the shielding plate below and then are fixedly connected to the base boss (311) at the four corners of the base (31). , 312, 313, 314) threaded holes. 3. A shielding structure for improving the performance of the fiber optic gyroscope fiber ring according to claim 1, characterized in that: one side of the base (31) has a base opening for passing through the two tail fibers of the fiber optic ring (315). 4. A shielding structure for improving the performance of a fiber optic gyroscope fiber ring according to claim 1, characterized in that: said shielding cover (11) includes a first shell (41) and a second shell nested in sequence (43), the third shell (45) and the fourth shell (47), the contact surface between the first shell (41) and the second shell (43) is provided with the first shielding shell (42), The contact surface between the second shell (43) and the third shell (45) is provided with a second shielding shell (44), and the contact surface between the third shell (45) and the fourth shell (47) A third shielding shell (46) is provided, and the adjacent shell layers (41) are fixedly connected with screw threaded holes after being nested with each other through shell bosses and through-hole structures. 5. A shielding structure for improving the performance of an optical fiber gyroscope fiber ring according to claim 1, characterized in that: the first shell (41), the second shell (43) and the third shell (45 ) are provided with flanges (414, 434, 454) on the bottom peripheral surface, and the bottom peripheral surface of the fourth shell (47) is provided with a flat plate (474) for cooperating with the inner bottom surface of the base (13), The flanges (414, 434, 454) of the first shell (41), the second shell (43) and the third shell (45) and the same side of the flat plate (474) of the fourth shell (47) are all provided with There are shell openings (411, 431, 451, 471) for passing through the two pigtails of the optical fiber ring, the flat plate (474) is provided with threaded holes (476), and the screws (12) pass through the threaded holes of the flat plate (474) in turn ( 476), loading board, each layer of partitions are fixedly linked on the base (31). 6. A shielding structure for improving the performance of the fiber optic gyroscope fiber ring according to claim 1, characterized in that: when installed in place, the shell openings and base openings of each shell layer are at the same side position, and can be combined in Together. 7. A shielding structure for improving the performance of the fiber optic ring of a fiber optic gyroscope according to claim 1, wherein the material of the base, the partition, the carrier plate and the shell layer is metal or engineering plastics. 8. A shielding structure for improving the performance of the fiber optic ring of a fiber optic gyroscope according to claim 1, characterized in that: each shielding plate and each shielding shell are selected from heat insulating materials, magnetic insulating materials or sound insulating materials.