CN117109551A - Polarization-maintaining ASE light source for high-precision fiber-optic gyroscope - Google Patents
Polarization-maintaining ASE light source for high-precision fiber-optic gyroscope Download PDFInfo
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- CN117109551A CN117109551A CN202310969467.6A CN202310969467A CN117109551A CN 117109551 A CN117109551 A CN 117109551A CN 202310969467 A CN202310969467 A CN 202310969467A CN 117109551 A CN117109551 A CN 117109551A
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- polarization maintaining
- light source
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- optic gyroscope
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- 230000010287 polarization Effects 0.000 claims abstract description 59
- 239000000835 fiber Substances 0.000 claims abstract description 33
- 239000013307 optical fiber Substances 0.000 claims abstract description 32
- 238000005086 pumping Methods 0.000 claims abstract description 22
- 230000003287 optical effect Effects 0.000 claims abstract description 20
- 238000002955 isolation Methods 0.000 claims description 16
- 208000025174 PANDAS Diseases 0.000 claims description 15
- 208000021155 Paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection Diseases 0.000 claims description 15
- 235000016496 Panda oleosa Nutrition 0.000 claims description 7
- 238000001914 filtration Methods 0.000 claims description 5
- 230000008033 biological extinction Effects 0.000 claims description 4
- 230000005284 excitation Effects 0.000 claims description 3
- 238000003466 welding Methods 0.000 claims description 3
- 240000000220 Panda oleosa Species 0.000 claims 1
- 240000004718 Panda Species 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 230000002269 spontaneous effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C19/00—Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
- G01C19/58—Turn-sensitive devices without moving masses
- G01C19/64—Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams
- G01C19/66—Ring laser gyrometers
- G01C19/661—Ring laser gyrometers details
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/024—Optical fibres with cladding with or without a coating with polarisation maintaining properties
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/06708—Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering
- H01S3/06712—Polarising fibre; Polariser
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/06708—Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering
- H01S3/06716—Fibre compositions or doping with active elements
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/10061—Polarization control
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- General Physics & Mathematics (AREA)
- Power Engineering (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Lasers (AREA)
Abstract
The invention discloses a polarization-preserving ASE light source for a high-precision fiber optic gyroscope, which comprises: the device comprises a pumping light source, a polarization maintaining integrated device, a polarizer, an erbium-doped optical fiber, a reflecting mirror, a photoelectric detector and a control circuit; the polarization maintaining integrated device comprises a pumping end, a public end, a signal end and a feedback end; the common end is connected with the erbium-doped optical fiber and then connected with the reflecting mirror; the signal end is used as the signal output end of the ASE light source, the feedback end is connected with the photoelectric detector, the photoelectric detector is connected with the control circuit, and the control circuit is connected with the pumping light source. The invention adopts the polarization maintaining integrated device to replace the wavelength division multiplexer, the optical fiber isolator and the beam splitter in the traditional optical path scheme, has simpler and more compact optical path structure on the basis of meeting the requirement of high-power output, uses fewer optical devices and is more suitable for the high-integration optical fiber gyro.
Description
Technical Field
The invention relates to the technical field of fiber-optic gyroscopes, in particular to a polarization-preserving ASE light source for a high-precision fiber-optic gyroscope.
Background
The fiber optic gyroscope is a high-precision solid inertial instrument for measuring the rotation angle rate by utilizing the Sagnac interference principle. To reduce noise generated by parasitic interference signals for optimal measurement, fiber optic gyroscopes typically choose an amplified spontaneous emission (Amplified Spontaneous Emission, ASE) source to provide the optical signal input. The full polarization maintaining scheme fiber optic gyroscope has higher precision in theory than the mixed polarization scheme fiber optic gyroscope, but is limited by a longer device tail fiber coiling fiber in the engineering assembly process, so that unavoidable polarization crosstalk is caused, and the ASE light source engineering application of the full polarization scheme is limited. Therefore, the ASE light source of the polarization maintaining scheme needs to solve the problems of integration and miniaturization of devices, reduce the length of a fiber, and ensure the polarization extinction ratio of an optical path. Meanwhile, the polarization-maintaining ASE light source can also be used for detecting polarization-maintaining devices such as Y waveguides in the fiber-optic gyroscope.
Disclosure of Invention
Aiming at least one defect or improvement requirement of the prior art, the invention provides a polarization-preserving ASE light source for a high-precision fiber optic gyroscope, which adopts a polarization-preserving integrated device to replace a wavelength division multiplexer, a fiber isolator and a beam splitter in the traditional optical path scheme, has simpler and more compact optical path structure on the basis of meeting high-power output, and is more suitable for the high-integration fiber optic gyroscope because fewer optical devices are used.
In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:
a polarization-maintaining ASE light source for a high-precision fiber-optic gyroscope comprises:
the device comprises a pumping light source, a polarization maintaining integrated device, a polarizer, an erbium-doped optical fiber, a reflecting mirror, a photoelectric detector and a control circuit; the polarization maintaining integrated device comprises a pumping end, a public end, a signal end and a feedback end;
the common end is connected with the erbium-doped optical fiber and then connected with the reflecting mirror;
the signal end is used as a signal output end of the ASE light source, the feedback end is connected with the photoelectric detector, the photoelectric detector is connected with the control circuit, and the control circuit is connected with the pumping light source.
As a preferred scheme of the invention, the polarization maintaining integrated device comprises a wavelength division multiplexing module, an optical isolation module and a light splitting module;
one side of the wavelength division multiplexing module is a pumping end and a public end of the polarization maintaining integrated device, and the other side of the wavelength division multiplexing module is connected with the optical isolation module; one side of the light splitting module is a signal end and a feedback end of the polarization maintaining integrated device, and the other side of the light splitting module is connected with the light isolation module.
As a preferable mode of the invention, the pumping light source is an LD pumping laser, and emits 980nm laser light.
As a preferred embodiment of the present invention, the polarizer is used to convert 1550nm laser light generated by the erbium-doped fiber under excitation of the pumping light source into linearly polarized light.
As a preferable scheme of the invention, the working wave band of the polarizer is 1550nm, and the tail fiber adopts panda-type polarization-maintaining fiber.
The pump end and the feedback end adopt single-mode optical fibers, the signal end and the common end adopt panda-type polarization maintaining optical fibers, and the common end and the polarizer tail optical fibers are welded in a panda-type polarization maintaining optical fiber counter-shaft welding mode.
As a preferable scheme of the invention, the wavelength division multiplexing module comprises a double-core collimating lens and a wavelength selective reflecting film which are connected, wherein the double-core collimating lens is externally connected with a single-mode optical fiber as the pumping end and is externally connected with a panda type polarization maintaining optical fiber as the public end, and the wavelength selective reflecting film is connected with the optical isolation module.
As a preferable scheme of the invention, the light splitting module comprises a collimating lens and a power filtering film which are connected, wherein the collimating lens is connected with the light isolation module, and the power filtering film is externally connected with a single-mode optical fiber as a feedback end and is externally connected with a panda-type polarization maintaining optical fiber as a signal end; the light splitting ratio of the light splitting module is 98:2.
As a preferable scheme of the invention, the common terminal of the polarization maintaining integrated device is the passing direction of the signal terminal, the opposite direction is the isolation direction, and the isolation degree of the signal terminal to the common terminal is not less than 55dB.
As a preferable scheme of the invention, the polarization state of the polarization maintaining integrated device works in a slow axis state, and the polarization extinction ratio is not less than 18dB.
Embodiments of the present invention have the following advantages:
the invention takes the polarization-preserving integrated device as the center, and constructs the polarization-preserving ASE light source with the double-pass amplifying structure. The polarization-preserving integrated device covers wavelength division multiplexing, optical isolation and optical splitting functions. By adopting the integrated device, the number of optical path devices can be greatly reduced, the optical path fiber quantity is reduced, polarization crosstalk caused by longer tail fiber disk fibers is controlled, and the spectrum modulation degree is deteriorated due to more device end surface reflection. The polarization-maintaining ASE light source has simple light path design, and the double-pass amplification scheme can improve the luminous efficiency of the erbium-doped optical fiber and simultaneously ensure that the output spectrum has optimal stability.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a polarization-maintaining ASE light source for a high-precision fiber-optic gyroscope according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a polarization maintaining integrated device according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
The terms first, second, third and the like in the description and in the claims and in the above drawings, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.
As shown in fig. 1, as a first embodiment of the present invention, there is provided a polarization maintaining ASE light source for a high-precision optical fiber gyro. In this embodiment, the light source includes a pump light source, a polarization maintaining integrated device, a polarizer, an erbium-doped fiber, a mirror, a photodetector, and a control circuit. The pumping light source in this embodiment is an LD pumping laser for generating 980nm laser. After 980nm laser enters the polarization maintaining integrated device through the pumping end, the 980nm laser is reflected to the public end by the device and enters the erbium-doped optical fiber. The erbium-doped optical fiber radiates 1550nm laser under the excitation of 980nm laser and transmits along the front and back directions simultaneously. In this embodiment, the reflector is selected as a faraday optical fiber reflector, and the forward light is reflected by the faraday optical fiber reflector, then enters the erbium-doped optical fiber again for secondary amplification, and is superimposed with the backward radiation light. In this embodiment, a polarizer is disposed between the erbium-doped fiber and the polarization-preserving integrated device, and the polarizer polarizes the superimposed 1550nm laser, and the polarized laser is converted into linearly polarized light and then enters the polarization-preserving integrated device from the public terminal. The 1550nm laser generates light splitting after passing through the polarization maintaining integrated device, wherein 98% of the light exits in a linear polarization state through the polarization maintaining tail fiber of the signal end, 2% of the light is output from the feedback end through the single-mode fiber and is used as a feedback control signal to be input to the photoelectric detector, and the photoelectric detector inputs the corresponding signal to the control circuit to form a closed loop feedback state.
As shown in fig. 2, the wavelength division multiplexing module inside the polarization maintaining integrated device in this embodiment is composed of a dual-core collimating lens and a wavelength selective reflecting film, wherein the wavelength selective reflecting film is used for reflecting 980nm laser generated by the LD pump laser and enabling 1550nm laser to transmit. In the light splitting module, the power filtering film couples the light beam into two light beams of 98% and 2% according to power so as to respectively realize the functions.
In this embodiment, the pump end and the feedback end select Hi1060flex single-mode pigtails; the common end and signal end tail fibers are panda type polarization maintaining fibers with the mode field diameter of 6.5+/-1.0 mu m, such as PM1550-80-18/165 panda type polarization maintaining fibers. The working wave band of the wavelength division multiplexing module is 980/1550nm. The Faraday optical reflector tail fiber selects Hi1060flex single-mode tail fiber, the working wave band of the polarizer is 1550nm, and the tail fiber selects panda type polarization-maintaining fiber with the mode field diameter of 6.5+/-1.0 mu m, such as PM1550-80-18/165 panda type polarization-maintaining fiber; the common end and the polarizer tail fiber are welded in a panda type polarization maintaining fiber counter-shaft welding mode. The light transmission direction in the polarization maintaining device is that the wavelength division multiplexing component is led to the light splitter component, and the isolation of the signal end to the public end is not less than 55dB. The polarization-preserving integrated device operates in a slow-axis state, and the polarization extinction ratio is not less than 18dB.
The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. A polarization maintaining ASE light source for a high-precision fiber-optic gyroscope is characterized by comprising:
the device comprises a pumping light source, a polarization maintaining integrated device, a polarizer, an erbium-doped optical fiber, a reflecting mirror, a photoelectric detector and a control circuit; the polarization maintaining integrated device comprises a pumping end, a public end, a signal end and a feedback end;
the common end is connected with the erbium-doped optical fiber and then connected with the reflecting mirror;
the signal end is used as a signal output end of the ASE light source, the feedback end is connected with the photoelectric detector, the photoelectric detector is connected with the control circuit, and the control circuit is connected with the pumping light source.
2. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the polarization maintaining integrated device comprises a wavelength division multiplexing module, an optical isolation module and a light splitting module;
one side of the wavelength division multiplexing module is a pumping end and a public end of the polarization maintaining integrated device, and the other side of the wavelength division multiplexing module is connected with the optical isolation module; one side of the light splitting module is a signal end and a feedback end of the polarization maintaining integrated device, and the other side of the light splitting module is connected with the light isolation module.
3. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the pumping light source is an LD pumping laser, and emits 980nm laser.
4. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the polarizer is used for converting 1550nm laser generated by the erbium-doped optical fiber under the excitation of the pumping light source into linearly polarized light.
5. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 4, wherein:
the working wave band of the polarizer is 1550nm, and the tail fiber adopts panda-type polarization-maintaining fiber.
6. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 5, wherein:
the pump end and the feedback end adopt single-mode optical fibers, the signal end and the common end adopt panda-type polarization maintaining optical fibers, and the common end and the polarizer tail optical fibers are welded in a panda-type polarization maintaining optical fiber counter-shaft welding mode.
7. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the wavelength division multiplexing module comprises a double-core collimating lens and a wavelength selective reflecting film which are connected, wherein the double-core collimating lens is externally connected with a single-mode optical fiber to serve as the pumping end, is externally connected with a panda type polarization maintaining optical fiber to serve as the public end, and the wavelength selective reflecting film is connected with the optical isolation module.
8. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the light splitting module comprises a collimating lens and a power filtering film which are connected, wherein the collimating lens is connected with the optical isolation module, and the power filtering film is externally connected with a single-mode optical fiber as a feedback end and is externally connected with a panda-type polarization maintaining optical fiber as a signal end; the light splitting ratio of the light splitting module is 98:2.
9. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the common end of the polarization maintaining integrated device is in a passing direction to the signal end, the reverse direction is in an isolation direction, and the isolation degree of the signal end to the common end is not less than 55dB.
10. The polarization maintaining ASE light source for high precision fiber-optic gyroscope of claim 1, wherein:
the polarization state of the polarization maintaining integrated device works in a slow axis state, and the polarization extinction ratio is not less than 18dB.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310969467.6A CN117109551A (en) | 2023-08-03 | 2023-08-03 | Polarization-maintaining ASE light source for high-precision fiber-optic gyroscope |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310969467.6A CN117109551A (en) | 2023-08-03 | 2023-08-03 | Polarization-maintaining ASE light source for high-precision fiber-optic gyroscope |
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| Publication Number | Publication Date |
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| CN117109551A true CN117109551A (en) | 2023-11-24 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310969467.6A Pending CN117109551A (en) | 2023-08-03 | 2023-08-03 | Polarization-maintaining ASE light source for high-precision fiber-optic gyroscope |
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| CN (1) | CN117109551A (en) |
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- 2023-08-03 CN CN202310969467.6A patent/CN117109551A/en active Pending
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