阅读说明：本技术 一种薄膜式光纤起偏器件 (Thin film type optical fiber polarizing device ) 是由 于佳 王夏霄 徐宏杰 马福 于 2020-03-27 设计创作，主要内容包括：本发明公开了一种薄膜式光纤起偏器件,采用光纤镀膜的方式实现起偏功能,所镀起偏膜由球状银纳米颗粒排列构成,银纳米颗粒分布具有二向色型性质,能够实现起偏功能,取代现有的光纤起偏器中的双折射晶体或者偏振片,从而可以简化光纤起偏器的结构,减小光纤起偏器的插入损耗及体积,降低加工成本。并且,通过光纤镀膜的方式实现起偏功能,由于没有增加额外的器件,因此,所镀起偏膜易与其他光波导进行耦合集成,结构灵活,能够实现多功能集成器件,非常适用于光纤电流传感和光纤陀螺领域。(The invention discloses a thin film type optical fiber polarizing device, which realizes the polarizing function by adopting an optical fiber coating mode, wherein the coated polarizing film is formed by arranging spherical silver nano particles, the silver nano particles have dichroic property, the polarizing function can be realized, and a birefringent crystal or a polarizing plate in the conventional optical fiber polarizer is replaced, so that the structure of the optical fiber polarizer can be simplified, the insertion loss and the volume of the optical fiber polarizer are reduced, and the processing cost is reduced. And moreover, the polarizing function is realized in an optical fiber film coating mode, and no additional device is added, so that the coated polarizing film is easy to be coupled and integrated with other optical waveguides, has a flexible structure, can realize a multifunctional integrated device, and is very suitable for the fields of optical fiber current sensing and optical fiber gyros.)

1. A method for manufacturing an all-fiber polarizer is characterized by comprising the following steps:

S1: inserting a single-mode optical fiber or a polarization maintaining optical fiber into a first single-core capillary tube, and inserting a single polarization maintaining optical fiber into a second single-core capillary tube;

S2: one end face of a first single-core capillary tube inserted with a single-mode optical fiber or a polarization-maintaining optical fiber is ground and then plated with a polarization-generating film, the other end of the first single-core capillary tube is used as an input end, one end face of a second single-core capillary tube inserted with a polarization-maintaining optical fiber is ground and then plated with an anti-reflection film, and the other end of the second single-core capillary tube is used as an output end; or, one end face of a first single-core capillary tube inserted with a single-mode optical fiber or a polarization maintaining optical fiber is ground and then plated with an anti-reflection film, the other end of the first single-core capillary tube is used as an input end, one end face of a second single-core capillary tube inserted with a polarization maintaining optical fiber is ground and then plated with a polarization film, and the other end of the second single-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

S3: and carrying out counter-shaft coupling on one end of the first single-core capillary coating film and one end of the second single-core capillary coating film oppositely, inputting linearly polarized light into the input end, monitoring the optical power and the extinction ratio of the output end, and fixedly packaging when the optical power and the extinction ratio of the output end reach the maximum values to obtain the all-fiber polarizer.

2. A method for manufacturing a 2 × 2 m: n polarization-maintaining coupler with polarization function is characterized by comprising the following steps:

S1: inserting double polarization maintaining optical fibers into a first double-core capillary tube, and inserting double polarization maintaining optical fibers into a second double-core capillary tube;

S2: grinding one end face of a first double-core capillary tube inserted with two polarization-maintaining optical fibers, plating a polarization film, taking the other end of the first double-core capillary tube as an input end, grinding one end face of a second double-core capillary tube inserted with two polarization-maintaining optical fibers, plating an anti-reflection film, and taking the other end of the second double-core capillary tube as an output end; or, one end face of a first double-core capillary tube inserted with two polarization-maintaining optical fibers is ground and then plated with an anti-reflection film, the other end of the first double-core capillary tube is used as an input end, one end face of a second double-core capillary tube inserted with two polarization-maintaining optical fibers is ground and then plated with a polarization-maintaining film, and the other end of the second double-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

S3: plating a thin film with the transmission and reflection ratio of m: n on the end surface of the first collimator facing the second collimator; wherein m: n ranges from 1:99 to 50: 50;

S4: sequentially arranging the first double-core capillary tube, the coated first collimator, the coated second collimator and the coated second double-core capillary tube for counter-shaft coupling; one end of the first double-core capillary coated film is opposite to the end face of the first collimator inclined by 8 degrees, and one end of the second double-core capillary coated film is opposite to the end face of the second collimator inclined by 8 degrees;

S5: linearly polarized light is input at one polarization maintaining optical fiber of the input end, the optical power and the extinction ratio of the other polarization maintaining optical fiber of the input end are monitored, and when the optical power and the extinction ratio of the other polarization maintaining optical fiber of the input end reach the maximum values, the first double-core capillary tube of the input end and the first collimator are fixed;

S6, inputting linearly polarized light at one polarization maintaining fiber of the output end, monitoring the optical power and extinction ratio of the other polarization maintaining fiber of the output end and the two polarization maintaining fibers of the input end, and fixing the second double-core capillary tube of the output end and the second collimator when the optical power and the extinction ratio of the other polarization maintaining fiber of the output end and the two polarization maintaining fibers of the input end reach the maximum values to obtain the 2 × 2 m: n polarization maintaining coupler with polarization function.

3. A method for manufacturing a 1 × 2 r: s polarization-maintaining coupler with polarization function is characterized by comprising the following steps:

S1: inserting a single polarization maintaining optical fiber into the single-core capillary, and inserting double polarization maintaining optical fibers into the double-core capillary;

S2: one end face of a single-core capillary tube inserted with a single polarization maintaining optical fiber is ground and then plated with a polarization generating film, the other end of the single-core capillary tube is used as an input end, one end face of a double-core capillary tube inserted with double polarization maintaining optical fibers is ground and then plated with an anti-reflection film, and the other end of the double-core capillary tube is used as an output end; or, one end face of a single-core capillary tube inserted with a single polarization maintaining optical fiber is ground and then plated with an anti-reflection film, the other end of the single-core capillary tube is used as an input end, one end face of a double-core capillary tube inserted with double polarization maintaining optical fibers is ground and then plated with a polarization film, and the other end of the double-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

S3: plating a thin film with the transmission and reflection ratio r: s on the end surface of the first collimator facing the second collimator; wherein r: s ranges from 1:99 to 50: 50;

S4: sequentially arranging the single-core capillary tube, the coated first collimator, the coated second collimator and the double-core capillary tube, and performing counter-shaft coupling; one end of the single-core capillary tube coating film is opposite to the end face of the first collimator inclined by 8 degrees, and one end of the double-core capillary tube coating film is opposite to the end face of the second collimator inclined by 8 degrees;

S5: linearly polarized light is input to the polarization maintaining optical fiber at the input end, the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end are monitored, and when the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end reach the maximum values, the single-core capillary tube at the input end is fixed with the first collimator;

S6, linearly polarized light is input at one polarization maintaining optical fiber of the output end, the optical power and the extinction ratio of the other polarization maintaining optical fiber of the output end and the polarization maintaining optical fiber of the input end are monitored, and when the optical power and the extinction ratio of the other polarization maintaining optical fiber of the output end and the polarization maintaining optical fiber of the input end reach the maximum values, the double-core capillary tube of the output end is fixed with the second collimator to obtain the 1 × 2 r: S polarization maintaining coupler with the polarization function.

Technical Field

The invention relates to the technical field of optical fiber sensing, in particular to a thin film type optical fiber polarizing device.

Background

The optical fiber sensing technology is developed along with the development of the optical fiber communication technology, and is a novel sensing technology which senses and transmits external measured signal quantity by taking optical fibers as media and light waves as carriers. The sensor has the advantages of small volume, light weight, high sensitivity, wide frequency band, large dynamic range, electromagnetic interference resistance, corrosion resistance, high pressure resistance, explosion resistance, flame resistance, good light path flexibility, easiness in realizing remote measurement, convenience in forming a sensor network, realization of multipoint measurement and the like, and is widely applied to the fields of national defense and military, aerospace, industrial and mining agriculture, energy environmental protection, automatic control, biomedicine, health care, metering test and the like.

The Saganc interference type optical fiber sensor is one of optical fiber sensors, and is mainly applied to optical fiber gyros and optical fiber current sensors. The optical path is a reciprocal structure, has good immunity to environmental interference such as vibration, temperature and the like, and only senses angular velocity and current signals. Two beams of linearly polarized light interfere after propagating in the interferometer, interference signals carry angular velocity and current signal information, and extraction of the angular velocity and current signals is achieved by detecting the signals. Therefore, it is necessary to control the polarization state of the light wave and convert the light wave into linearly polarized light.

Currently, the commonly used optical fiber polarizers, such as birefringent crystal type or polarizer type, have relatively complex structures, need to be bonded by glue, and have relatively large volumes. The application temperature of the optical fiber gyroscope and the optical fiber current sensor is-40-70 ℃, and in order to meet the requirements of low cost, miniaturization and the like, the structure of the optical fiber polarizer needs to be as simple as possible and easy to realize.

Disclosure of Invention

In view of this, the present invention provides a thin film type optical fiber polarizer, which is used to meet the application requirements of low cost and miniaturization of optical fiber sensing.

Therefore, the invention provides a method for manufacturing an all-fiber polarizer, which comprises the following steps:

S1: inserting a single-mode optical fiber or a polarization maintaining optical fiber into a first single-core capillary tube, and inserting a single polarization maintaining optical fiber into a second single-core capillary tube;

S2: one end face of a first single-core capillary tube inserted with a single-mode optical fiber or a polarization-maintaining optical fiber is ground and then plated with a polarization-generating film, the other end of the first single-core capillary tube is used as an input end, one end face of a second single-core capillary tube inserted with a polarization-maintaining optical fiber is ground and then plated with an anti-reflection film, and the other end of the second single-core capillary tube is used as an output end; or, one end face of a first single-core capillary tube inserted with a single-mode optical fiber or a polarization maintaining optical fiber is ground and then plated with an anti-reflection film, the other end of the first single-core capillary tube is used as an input end, one end face of a second single-core capillary tube inserted with a polarization maintaining optical fiber is ground and then plated with a polarization film, and the other end of the second single-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

S3: and carrying out counter-shaft coupling on one end of the first single-core capillary coating film and one end of the second single-core capillary coating film oppositely, inputting linearly polarized light into the input end, monitoring the optical power and the extinction ratio of the output end, and fixedly packaging when the optical power and the extinction ratio of the output end reach the maximum values to obtain the all-fiber polarizer.

the invention also provides a manufacturing method of the 2 × 2 m: n polarization-maintaining coupler with the polarization function, which comprises the following steps:

S1: inserting double polarization maintaining optical fibers into a first double-core capillary tube, and inserting double polarization maintaining optical fibers into a second double-core capillary tube;

S2: grinding one end face of a first double-core capillary tube inserted with two polarization-maintaining optical fibers, plating a polarization film, taking the other end of the first double-core capillary tube as an input end, grinding one end face of a second double-core capillary tube inserted with two polarization-maintaining optical fibers, plating an anti-reflection film, and taking the other end of the second double-core capillary tube as an output end; or, one end face of a first double-core capillary tube inserted with two polarization-maintaining optical fibers is ground and then plated with an anti-reflection film, the other end of the first double-core capillary tube is used as an input end, one end face of a second double-core capillary tube inserted with two polarization-maintaining optical fibers is ground and then plated with a polarization-maintaining film, and the other end of the second double-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

S3: plating a thin film with the transmission and reflection ratio of m: n on the end surface of the first collimator facing the second collimator; wherein m: n ranges from 1:99 to 50: 50;

S4: sequentially arranging the first double-core capillary tube, the coated first collimator, the coated second collimator and the coated second double-core capillary tube for counter-shaft coupling; one end of the first double-core capillary coated film is opposite to the end face of the first collimator inclined by 8 degrees, one end of the second double-core capillary coated film is opposite to the end face of the second collimator inclined by 8 degrees, and counter-shaft coupling is carried out;

S5: linearly polarized light is input at one polarization maintaining optical fiber of the input end, the optical power and the extinction ratio of the other polarization maintaining optical fiber of the input end are monitored, and when the optical power and the extinction ratio of the other polarization maintaining optical fiber of the input end reach the maximum values, the first double-core capillary tube of the input end and the first collimator are fixed;

S6, inputting linearly polarized light at one polarization maintaining fiber of the output end, monitoring the optical power and extinction ratio of the other polarization maintaining fiber of the output end and the two polarization maintaining fibers of the input end, and fixing the second double-core capillary tube of the output end and the second collimator when the optical power and the extinction ratio of the other polarization maintaining fiber of the output end and the two polarization maintaining fibers of the input end reach the maximum values to obtain the 2 × 2 m: n polarization maintaining coupler with polarization function.

the invention also provides a manufacturing method of the 1 × 2 r: s polarization-maintaining coupler with the polarization function, which comprises the following steps:

S1: inserting a single polarization maintaining optical fiber into the single-core capillary, and inserting double polarization maintaining optical fibers into the double-core capillary;

S2: one end face of a single-core capillary tube inserted with a single polarization maintaining optical fiber is ground and then plated with a polarization generating film, the other end of the single-core capillary tube is used as an input end, one end face of a double-core capillary tube inserted with double polarization maintaining optical fibers is ground and then plated with an anti-reflection film, and the other end of the double-core capillary tube is used as an output end; or, one end face of a single-core capillary tube inserted with a single polarization maintaining optical fiber is ground and then plated with an anti-reflection film, the other end of the single-core capillary tube is used as an input end, one end face of a double-core capillary tube inserted with double polarization maintaining optical fibers is ground and then plated with a polarization film, and the other end of the double-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

S3: plating a thin film with the transmission and reflection ratio r: s on the end surface of the first collimator facing the second collimator; wherein r: s ranges from 1:99 to 50: 50;

S4: sequentially arranging the single-core capillary tube, the coated first collimator, the coated second collimator and the double-core capillary tube, and performing counter-shaft coupling; one end of the single-core capillary tube coating film is opposite to the end face of the first collimator inclined by 8 degrees, and one end of the double-core capillary tube coating film is opposite to the end face of the second collimator inclined by 8 degrees;

S5: linearly polarized light is input to the polarization maintaining optical fiber at the input end, the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end are monitored, and when the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end reach the maximum values, the single-core capillary tube at the input end is fixed with the first collimator;

S6, linearly polarized light is input at one polarization maintaining optical fiber of the output end, the optical power and the extinction ratio of the other polarization maintaining optical fiber of the output end and the polarization maintaining optical fiber of the input end are monitored, and when the optical power and the extinction ratio of the other polarization maintaining optical fiber of the output end and the polarization maintaining optical fiber of the input end reach the maximum values, the double-core capillary tube of the output end is fixed with the second collimator to obtain the 1 × 2 r: S polarization maintaining coupler with the polarization function.

The thin-film optical fiber polarizing device provided by the invention realizes the polarizing function by adopting an optical fiber coating mode, the coated polarizing film is formed by arranging spherical silver nanoparticles, the silver nanoparticles are distributed to have dichroic properties, the polarizing function can be realized, and a birefringent crystal or a polarizing plate in the conventional optical fiber polarizer is replaced, so that the structure of the optical fiber polarizer can be simplified, the insertion loss and the volume of the optical fiber polarizer can be reduced, and the processing cost can be reduced. And moreover, the polarizing function is realized in an optical fiber film coating mode, and no additional device is added, so that the coated polarizing film is easy to be coupled and integrated with other optical waveguides, has a flexible structure, can realize a multifunctional integrated device, and is very suitable for the fields of optical fiber current sensing and optical fiber gyros.

Drawings

FIG. 1 is a flow chart of a method for manufacturing an all-fiber polarizer according to the present invention;

FIG. 2 is a schematic structural diagram of an all-fiber polarizer obtained by the method for manufacturing an all-fiber polarizer according to the present invention;

FIG. 3 is a flow chart of a method for manufacturing a 2 × 2 polarization maintaining coupler with m: n polarization function according to the present invention;

FIG. 4 is a schematic structural diagram of a 2 × 2 polarization maintaining coupler with polarization function obtained by the method for manufacturing a 2 × 2 polarization maintaining coupler with polarization function;

FIG. 5 is a flow chart of a method for manufacturing a 1 × 2 polarization-maintaining r: s coupler according to the present invention;

fig. 6 is a schematic structural diagram of a 1 × 2 r: s polarization maintaining coupler with polarization function obtained by using the manufacturing method of the 1 × 2 r: s polarization maintaining coupler with polarization function provided by the invention.

Reference numerals: 1. a first single-core capillary tube; 2. a single mode optical fiber; 3. a second single-core capillary tube; 4. a polarization maintaining optical fiber; 5. eliminating the reverse film; 6. polarizing the film; 7. a glass tube; 8. a first dual-wick capillary tube; 9. a second dual-wick capillary; 10. a first collimator; 11. a semi-permeable and semi-reflective film; 12. a second collimator; 13. a single-core capillary tube; 14. a dual wick capillary.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only illustrative and are not intended to limit the present invention.

The invention provides a method for manufacturing an all-fiber polarizer, which comprises the following steps as shown in figure 1:

S1: inserting a single-mode optical fiber or a polarization maintaining optical fiber into a first single-core capillary tube, and inserting a single polarization maintaining optical fiber into a second single-core capillary tube;

S2: one end face of a first single-core capillary tube inserted with a single-mode optical fiber or a polarization-maintaining optical fiber is ground and then plated with a polarization-generating film, the other end of the first single-core capillary tube is used as an input end, one end face of a second single-core capillary tube inserted with a polarization-maintaining optical fiber is ground and then plated with an anti-reflection film, and the other end of the second single-core capillary tube is used as an output end; or, one end face of a first single-core capillary tube inserted with a single-mode optical fiber or a polarization maintaining optical fiber is ground and then plated with an anti-reflection film, the other end of the first single-core capillary tube is used as an input end, one end face of a second single-core capillary tube inserted with a polarization maintaining optical fiber is ground and then plated with a polarization film, and the other end of the second single-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

Specifically, the silver nanoparticles in the polarizing film are distributed to have dichroic properties, so that the polarizing function can be realized;

S3: one end of a first single-core capillary film coating is opposite to one end of a second single-core capillary film coating to carry out counter-shaft coupling, linearly polarized light is input at an input end, the optical power and the extinction ratio of an output end are monitored, and fixed packaging is carried out when the optical power and the extinction ratio of the output end reach the maximum values, so that the all-fiber polarizer is obtained;

Specifically, the input end of the all-fiber polarizer is a single-mode fiber or a polarization maintaining fiber, and the output end of the all-fiber polarizer is a polarization maintaining fiber, and the all-fiber polarizer can be used for a fiber current sensor.

In a specific implementation, in the method for manufacturing the all-fiber polarizer provided by the present invention, in steps S1 and S2, the anti-reflection film may be deposited by vacuum evaporation.

In specific implementation, in the method for manufacturing the all-fiber polarizer provided by the invention, in step S3, when the optical power and the extinction ratio at the output end both reach the maximum values, two single-core capillary tubes after being coupled to a shaft may be placed in a glass tube, a small amount of uv glue is dispensed at the input end and the output end, and the uv glue is irradiated by an ultraviolet lamp for curing, so that fixed packaging is realized.

In the figure 2, a single-mode optical fiber 2 is inserted into a first single-core capillary 1, a single polarization maintaining optical fiber 4 is inserted into a second single-core capillary 3, a reflection eliminating film 5 is plated at one end of the first single-core capillary 1, a polarization generating film 6 is plated at one end of the second single-core capillary 3, and the single-mode optical fiber and the polarization maintaining optical fiber are placed into a glass tube 7 and are fixedly packaged through ultraviolet glue after being coupled to a shaft.

based on the same inventive concept, the invention also provides a manufacturing method of the 2 × 2 m: n polarization-maintaining coupler with the polarization function, as shown in fig. 3, comprising the following steps:

S1: inserting double polarization maintaining optical fibers into a first double-core capillary tube, and inserting double polarization maintaining optical fibers into a second double-core capillary tube;

S2: grinding one end face of a first double-core capillary tube inserted with two polarization-maintaining optical fibers, plating a polarization film, taking the other end of the first double-core capillary tube as an input end, grinding one end face of a second double-core capillary tube inserted with two polarization-maintaining optical fibers, plating an anti-reflection film, and taking the other end of the second double-core capillary tube as an output end; or, one end face of a first double-core capillary tube inserted with two polarization-maintaining optical fibers is ground and then plated with an anti-reflection film, the other end of the first double-core capillary tube is used as an input end, one end face of a second double-core capillary tube inserted with two polarization-maintaining optical fibers is ground and then plated with a polarization-maintaining film, and the other end of the second double-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

Specifically, the silver nanoparticles in the polarizing film are distributed to have dichroic properties, so that the polarizing function can be realized;

S3: plating a thin film with the transmission and reflection ratio of m: n on the end surface of the first collimator facing the second collimator; wherein m: n ranges from 1:99 to 50: 50;

S4: sequentially arranging the first double-core capillary tube, the coated first collimator, the coated second collimator and the coated second double-core capillary tube, and performing counter-shaft coupling; one end of the first double-core capillary coated film is opposite to the end face of the first collimator inclined by 8 degrees, and one end of the second double-core capillary coated film is opposite to the end face of the second collimator inclined by 8 degrees;

S5: linearly polarized light is input at one polarization maintaining optical fiber at the input end, the optical power and the extinction ratio of the other polarization maintaining optical fiber at the input end are monitored, and when the optical power and the extinction ratio of the other polarization maintaining optical fiber at the input end reach the maximum values, the first double-core capillary tube at the input end is fixed with the first collimator;

S6, inputting linearly polarized light at one polarization maintaining fiber at the output end, monitoring the optical power and extinction ratio of the other polarization maintaining fiber at the output end and the two polarization maintaining fibers at the input end, and fixing a second double-core capillary tube at the output end with a second collimator when the optical power and the extinction ratio of the other polarization maintaining fiber at the output end and the two polarization maintaining fibers at the input end reach the maximum values to obtain a 2 × 2 m: n polarization maintaining coupler with a polarization function;

specifically, the input end and the output end of the 2 × 2 m: n polarization-maintaining coupler with the polarization function are both polarization-maintaining optical fibers, and the coupler can be used for an optical fiber gyro intensity noise cancellation optical path.

in a specific implementation, in the method for manufacturing the 2 × 2 m: n polarization maintaining coupler with polarization function provided by the present invention, the anti-reflection film can be deposited by a vacuum evaporation method in steps S1 and S2.

in a specific implementation, in the method for manufacturing the 2 × 2 m: n polarization maintaining coupler with polarization maintaining function provided by the present invention, in step S5, when the optical power and the extinction ratio of another polarization maintaining fiber at the input end reach the maximum values, and the first dual-core capillary and the first collimator at the input end are fixed, the first dual-core capillary and the first collimator at the input end may be placed in a glass tube, a small amount of uv glue is dispensed at the input end, and the uv glue is irradiated by an ultraviolet lamp for curing, so as to implement fixed packaging.

in specific implementation, in the method for manufacturing the 2 × 2 m: n polarization maintaining coupler with polarization function provided by the present invention, in step S6, when the optical power and the extinction ratio of the other polarization maintaining fiber at the output end and the two polarization maintaining fibers at the input end both reach the maximum values, and the second dual-core capillary tube at the output end and the second collimator are fixed, the second dual-core capillary tube at the output end and the second collimator may be placed in a glass tube, a small amount of uv glue is dispensed at the output end, and the uv glue is irradiated by an ultraviolet lamp for curing, so as to realize fixed packaging.

As shown in fig. 4, a double polarization maintaining fiber 4 is inserted into a first double-core capillary 8, a double polarization maintaining fiber 4 is inserted into a second double-core capillary 9, fig. 4 takes the example that one end of the first double-core capillary 8 is plated with a polarization film 6, one end of the second double-core capillary 9 is plated with an anti-reflection film 5, the end surface of the first collimator 10 opposite to the end surface inclined at 8 degrees is plated with a semi-transparent semi-reflection film 11 (i.e. the transmission-reflection ratio is 50:50), and the second collimator 12 is not plated with a film, and the two double-core capillary is coupled to a shaft and then placed into a glass tube 7 and fixedly packaged by ultraviolet glue.

based on the same inventive concept, the invention also provides a method for manufacturing the 1 × 2 r: s polarization-maintaining coupler with polarization function, as shown in fig. 5, comprising the following steps:

S1: inserting a single polarization maintaining optical fiber into the single-core capillary, and inserting double polarization maintaining optical fibers into the double-core capillary;

S2: one end face of a single-core capillary tube inserted with a single polarization maintaining optical fiber is ground and then plated with a polarization generating film, the other end of the single-core capillary tube is used as an input end, one end face of a double-core capillary tube inserted with double polarization maintaining optical fibers is ground and then plated with an anti-reflection film, and the other end of the double-core capillary tube is used as an output end; or, one end face of a single-core capillary tube inserted with a single polarization maintaining optical fiber is ground and then plated with an anti-reflection film, the other end of the single-core capillary tube is used as an input end, one end face of a double-core capillary tube inserted with double polarization maintaining optical fibers is ground and then plated with a polarization film, and the other end of the double-core capillary tube is used as an output end; the polarizing film is prepared by adopting ultrahigh vacuum magnetron sputtering and ion beam composite plating, is formed by arranging spherical silver nanoparticles, and controls the arrangement structure of the silver nanoparticles by controlling sputtering power;

Specifically, the distribution of the silver nanoparticles in the polarizing film has dichroic properties, and the polarizing function can be realized

S3: plating a thin film with the transmission and reflection ratio r: s on the end surface of the first collimator facing the second collimator; wherein r: s ranges from 1:99 to 50: 50;

S4: sequentially arranging the single-core capillary tube, the coated first collimator, the coated second collimator and the double-core capillary tube, and performing counter-shaft coupling; one end of the single-core capillary tube coating film is opposite to the end face of the first collimator inclined by 8 degrees, and one end of the double-core capillary tube coating film is opposite to the end face of the second collimator inclined by 8 degrees;

S5: linearly polarized light is input at the polarization maintaining optical fiber at the input end, the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end are monitored, and when the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end reach the maximum values, the single-core capillary tube at the input end is fixed with the first collimator;

S6, inputting linearly polarized light at one polarization maintaining fiber at the output end, monitoring the optical power and extinction ratio of the other polarization maintaining fiber at the output end and the polarization maintaining fiber at the input end, and fixing the double-core capillary tube at the output end and a second collimator when the optical power and the extinction ratio of the other polarization maintaining fiber at the output end and the polarization maintaining fiber at the input end reach the maximum values to obtain a 1 × 2 r: S polarization maintaining coupler with polarization function;

specifically, the input end and the output end of the 1 × 2 r: s polarization-maintaining coupler with the polarization function are both polarization-maintaining optical fibers, and the coupler can be used for an optical fiber gyro intensity noise cancellation optical path.

in a specific implementation, in the method for manufacturing the 1 × 2 r: S polarization maintaining coupler with polarization function provided by the present invention, the anti-reflection film can be deposited by a vacuum evaporation method in steps S1 and S2.

in specific implementation, in the method for manufacturing the 1 × 2 r: S polarization maintaining coupler with polarization maintaining function provided by the invention, in step S5, when the optical power and the extinction ratio of the two polarization maintaining optical fibers at the output end reach the maximum values, and the single-core capillary tube at the input end and the first collimator are fixed, the single-core capillary tube at the input end and the first collimator can be placed in a glass tube, a small amount of ultraviolet glue is dispensed at the input end, and the ultraviolet glue is irradiated by an ultraviolet lamp for curing, so that fixed packaging is realized.

in specific implementation, in the method for manufacturing the 1 × 2 r: S polarization maintaining coupler with polarization maintaining function provided by the invention, in step S6, when the optical power and extinction ratio of the other polarization maintaining fiber at the output end and the polarization maintaining fiber at the input end reach the maximum values, and the dual-core capillary tube at the output end and the second collimator are fixed, the dual-core capillary tube at the output end and the second collimator can be put into a glass tube, a small amount of ultraviolet glue is dispensed at the output end, and the ultraviolet glue is irradiated by an ultraviolet lamp for curing, so that fixed packaging is realized.

As shown in fig. 6, a single polarization maintaining fiber 4 is inserted into a single-core capillary 13, two polarization maintaining fibers 4 are inserted into a double-core capillary 14, fig. 6 is characterized in that one end of the single-core capillary 13 is plated with a polarization film 6, one end of the double-core capillary 14 is plated with an anti-reflection film 5, a semi-transparent semi-reflection film 11 is plated on the end surface of the first collimator 10 opposite to the end surface inclined at 8 degrees (namely, the transmission-reflection ratio is 50:50), and the second collimator 12 is not plated with a film, and is placed into a glass tube 7 after being coupled with a counter shaft and is fixedly packaged through ultraviolet glue.

The thin-film optical fiber polarizing device provided by the invention realizes the polarizing function by adopting an optical fiber coating mode, the coated polarizing film is formed by arranging spherical silver nanoparticles, the silver nanoparticles are distributed to have dichroic properties, the polarizing function can be realized, and a birefringent crystal or a polarizing plate in the conventional optical fiber polarizer is replaced, so that the structure of the optical fiber polarizer can be simplified, the insertion loss and the volume of the optical fiber polarizer can be reduced, and the processing cost can be reduced. And moreover, the polarizing function is realized in an optical fiber film coating mode, and no additional device is added, so that the coated polarizing film is easy to be coupled and integrated with other optical waveguides, has a flexible structure, can realize a multifunctional integrated device, and is very suitable for the fields of optical fiber current sensing and optical fiber gyros.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.