CN108303180B - Vector light measuring device based on optical geometric transformation - Google Patents
Vector light measuring device based on optical geometric transformation Download PDFInfo
- Publication number
- CN108303180B CN108303180B CN201810253913.2A CN201810253913A CN108303180B CN 108303180 B CN108303180 B CN 108303180B CN 201810253913 A CN201810253913 A CN 201810253913A CN 108303180 B CN108303180 B CN 108303180B
- Authority
- CN
- China
- Prior art keywords
- optical
- measuring device
- geometric transformation
- vector light
- main body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 66
- 230000009466 transformation Effects 0.000 title claims abstract description 25
- 230000010287 polarization Effects 0.000 claims abstract description 28
- 239000000835 fiber Substances 0.000 claims abstract description 14
- 239000004973 liquid crystal related substance Substances 0.000 claims abstract description 12
- 238000007493 shaping process Methods 0.000 claims abstract description 10
- 239000013307 optical fiber Substances 0.000 claims description 9
- 239000013078 crystal Substances 0.000 claims description 4
- 239000000919 ceramic Substances 0.000 claims description 2
- 239000011521 glass Substances 0.000 claims description 2
- 229920000620 organic polymer Polymers 0.000 claims description 2
- 239000012780 transparent material Substances 0.000 claims description 2
- 238000005259 measurement Methods 0.000 abstract description 15
- 238000004891 communication Methods 0.000 abstract description 9
- 230000008901 benefit Effects 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 238000010521 absorption reaction Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000011426 transformation method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000012634 optical imaging Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J4/00—Measuring polarisation of light
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
- G02B27/283—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising used for beam splitting or combining
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3016—Polarising elements involving passive liquid crystal elements
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Polarising Elements (AREA)
Abstract
The invention relates to the technical field of vector light measurement, in particular to a vector light measuring device based on optical geometric transformation. The device comprises a measuring device main body and an optical power meter; the single mode fiber is arranged at one end of the measuring device main body, and the output optical power of the single mode fiber can be directly read by an optical power meter. The measurer main body is an integrated optical free-form surface device, which comprises a liquid crystal polarization grating, an optical geometric transformation area, a phase compensation focusing area and a beam shaping area, and comprises two completely symmetrical parts. The intervals among the optical geometry transformation area, the phase compensation focusing area and the light beam shaping area are completely equal. The device has the advantages of low loss, high flexibility, convenient use and the like, and can be widely applied to the fields of vector light measurement, coding communication and the like.
Description
Technical Field
The invention relates to the technical field of vector light measurement, in particular to a vector light measuring device based on optical geometric transformation.
Background
Vector light is a spatial mode in which the polarization state changes at every point in space. Vector light has important research value in the fields of optical particle manipulation, optical imaging, optical communication, optical storage, optical sensing and the like due to the unique characteristics of focusing property, polarization characteristic, topological structure and the like, and particularly has great potential in the field of optical communication as a mode multiplexing mode. Most notably, vector light known as vector vortex rotation.
The topological order of polarization of vector vortex rotation, also commonly referred to as cylindrical vector light (CVB) or cylindrical vector mode, can be defined as the number of repetitions of the 360 ° polarization state change along the azimuthal axis, with the sign indicating the direction of rotation of the polarization.
Frequency division and wavelength division multiplexing are mainstream optical communication multiplexing technologies at present, and with the existing communication capacity and bandwidth bottleneck, a novel multiplexing technology is needed. And because the vector light is an eigenmode in the optical fiber and the vector lights in different polarization states are orthogonal to each other, the vector light multiplexing can greatly improve the optical communication capacity. In addition, vector light can also be used for coded communication by utilizing the limitless polarization topological order of vector vortex rotation.
However, how to judge the polarization topological order of the vector vortex rotation is still a difficult problem, and further development and application of the vector vortex rotation are prevented.
At present, the method for measuring the topological order of vector vortex light polarization is less. In 2015, Milione et al performed measurements using q-slides, but this method only measured one vector vortex rotation at a time and was complicated. In 2015, Moreno et al mainly use eddy current sensing diffraction gratings for measurement, but vector eddy light measured by the measurement method is limited to specific types, and the loss is large, which is not favorable for application of an actual communication system.
In order to improve the accuracy and the measurement range of the measurement, an optical geometric transformation method can be considered to be introduced into the measurement of the topological order of the vector vortex light polarization. Because the vector vortex light can be regarded as the superposition of two beams of left and right vortex optical rotations with opposite topological charges, the measurement problem of the topological order of the polarization of the vector vortex light can be converted into the measurement problem of the vortex optical rotation topological charges. In 2010, Berkhout et al propose that a Cartesian-polar coordinate-based optical geometry transformation method can be used for measuring the vortex optical topological charge. Vortex light can be expanded into inclined plane waves with phase gradients through optical geometric transformation, and the vortex light with different topological charges can be focused to different transverse positions through the focusing of the lens, so that efficient separation is realized. Theoretically, the optical geometric transformation has no energy loss except for the loss caused by the optical device, and thus has the advantage of low loss. The vector vortex light polarization topological order can be obtained by measuring the left-handed and right-handed vortex optical rotation. In consideration of simplicity and wavelength universality, the integrated optical device can be processed based on the method and can be better applied to actual measurement.
Disclosure of Invention
In order to overcome at least one defect in the prior art, the invention provides a vector light measuring device based on optical geometric transformation, wherein an integrated optical device is manufactured by adopting a method of changing the crystal axis and refractive index distribution of a material by a femtosecond laser, and the integrated optical device is used for realizing simpler and more convenient measurement of the topological order of vector vortex light polarization.
The technical scheme of the invention is as follows: a vector light measuring device based on optical geometric transformation comprises a measuring device main body, a single mode fiber and an optical power meter, wherein the single mode fiber is arranged at one end of the measuring device main body, and the optical power meter can be connected with the single mode fiber and can directly read the output optical power of the single mode fiber; the measuring device main body is an integrated optical device and comprises a liquid crystal polarization grating, an optical geometric transformation area, a phase compensation focusing area and a light beam shaping area; the optical geometric transformation area, the phase compensation focusing area and the light beam shaping area are distributed at equal intervals.
Furthermore, the liquid crystal polarization grating in the measuring device main body is made of liquid crystal, and the optical geometric transformation area, the phase compensation focusing area and the beam shaping area are made of glass, ceramics, crystals and organic polymer transparent materials.
The device adopts femtosecond laser as a processing method; for the liquid crystal polarization grating, femtosecond laser irradiates liquid crystal to ensure that crystal axes in the liquid crystal are distributed according to a certain rule, so that the liquid crystal can separate left-handed and right-handed circularly polarized light and the separated left-handed and right-handed circularly polarized light is transmitted according to a specific direction; for the optical geometry transformation area, the phase compensation focusing area and the beam shaping area, femtosecond laser heats an irradiated material area to induce the refractive index of the irradiated material area to change, so that the specific refractive index area distribution is inscribed in the material, and finally, the area is packaged into an integrated optical component, namely the measuring device main body.
Furthermore, the measuring device main body can separate the vector light into two beams of circularly polarized vortex optical rotation, and the polarization topological order of the vector light is finally measured by measuring the topological charge of the two beams of circularly polarized vortex optical rotation.
Furthermore, the number of the single mode fibers is multiple, and the number of the single mode fibers can be changed according to needs.
Further, the input vector light of the measuring device body can be any frequency and wavelength.
Compared with the prior art, the beneficial effects are: the device has the characteristic of integration, and the total loss of the device is small; the loss of the device mainly comes from optical fiber coupling and material absorption; there are no other losses in addition. The device has an external structure coupled with the optical fiber, can be used only by directly accessing the optical fiber during use, and is convenient to use and high in accuracy.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the patent; for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted. The positional relationships depicted in the drawings are for illustrative purposes only and are not to be construed as limiting the present patent.
Mode 1:
as shown in fig. 1, the end connected with the single-mode fiber is an output end, and a vector vortex rotation is input to the other end, and the vector vortex rotation may be directly irradiated onto the measurement device or may be incident into the device through fiber coupling.
For vector vortex optical rotation with a single polarization topological order, after passing through a liquid crystal polarization grating, the vector vortex optical rotation is divided into two beams of circularly polarized light, one beam is left vortex optical rotation, the other beam is right vortex optical rotation, and the topological charges are assumed to be m and-m respectively. The left-handed vortex light and the right-handed vortex light respectively propagate to the optical geometry transformation areas corresponding to 1.2 and 1.3 according to preset paths. 1.2 and 1.3 are identical geometric transformation zones. After passing through the geometric transformation area, the left-handed vortex light and the right-handed vortex light can be gradually unfolded, and rectangular light spots are respectively formed in the phase compensation focusing areas corresponding to 1.4 and 1.5 through a distance, supposing d, but the phases of the rectangular light spots at the moment are disordered. And then the inclined plane waves with phase gradients are formed through the phase correction corresponding to the 1.4 and the 1.5 respectively, and the phase gradients are changed linearly according to different topological charges. Since the phase compensation focusing region has a focusing function, the inclined plane waves are respectively focused into long strip-shaped light spots after passing through the same propagation distance d. And the position of the strip-shaped light spot and the specific values m and-m of the topological load. Then, the strip-shaped light spots pass through the beam shaping area and are shaped into Gaussian-like light in each corresponding small area, and the Gaussian-like light can be coupled into the single-mode optical fiber. Therefore, according to the output optical power of the coupled single mode fiber, the values m and-m corresponding to the topological charges can be determined according to the position of the fiber with the maximum output optical power. m is the corresponding polarization topology charge order.
Mode 2:
for the composite vector vortex rotation of multiple polarization topological orders, assuming that there are two polarization topological charge numbers to be compounded, then for each of the vector vortex optical modes, the process is performed as described above.
Assuming that the topological charge number of the finally measured vortex rotation is m, n, -m, -n, the vector vortex rotation is formed by
The polarization topological charge is formed by compounding m and n vector vortex light.
The input vector vortex light can be any frequency and wavelength, so the applicability is wide. The integration of the measuring device ensures that the optical conversion process is completed inside the device, does not receive the disturbance of air, is slightly influenced by the outside and has stable work.
The device is mainly a refraction type device, and except a small amount of scattering and absorption, the loss of other redundant energy is small, so that the efficiency is high, and the measurement result is accurate.
The application of the invention in the measurement of the load order of the vector light polarization topology can be used for further paving and preparing the best technology for optical communication by utilizing the vector light.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (5)
1. The vector light measuring device based on optical geometric transformation is characterized by comprising a measuring device main body (1), a single-mode optical fiber (2) and an optical power meter (3), wherein the single-mode optical fiber (2) is arranged at one end of the measuring device main body (1), and the optical power meter (3) is connected with the single-mode optical fiber (2) and can directly read the output optical power of the single-mode optical fiber; the measuring device main body (1) is an integrated optical device and comprises a liquid crystal polarization grating (1.1), optical geometric transformation areas (1.2,1.3), phase compensation focusing areas (1.4,1.5) and beam shaping areas (1.6, 1.7); the optical geometry transformation areas (1.2,1.3), the phase compensation focusing areas (1.4,1.5) and the beam shaping areas (1.6,1.7) are distributed at equal intervals.
2. The vector light measuring device based on optical geometric transformation as claimed in claim 1, wherein: the liquid crystal polarization grating (1.1) in the measuring device main body (1) is made of liquid crystal, and any one of the optical geometric transformation areas (1.2,1.3), the phase compensation focusing areas (1.4,1.5) and the beam shaping areas (1.6,1.7) is made of glass, ceramic, crystal or organic polymer transparent materials.
3. The vector light measuring device based on optical geometric transformation as claimed in claim 1, wherein: the measuring device main body can separate the vector light into two beams of circularly polarized vortex optical rotation, and the polarization topological order of the vector light is finally measured by measuring the topological charge of the two beams of circularly polarized vortex optical rotation.
4. The vector light measuring device based on optical geometric transformation as claimed in claim 1, wherein: the number of the single-mode fibers (2) is multiple, and the number of the single-mode fibers can be changed according to needs.
5. The vector light measuring device based on optical geometric transformation as claimed in claim 1, wherein: the input vector light of the measuring device main body (1) is any frequency.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810253913.2A CN108303180B (en) | 2018-03-26 | 2018-03-26 | Vector light measuring device based on optical geometric transformation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810253913.2A CN108303180B (en) | 2018-03-26 | 2018-03-26 | Vector light measuring device based on optical geometric transformation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108303180A CN108303180A (en) | 2018-07-20 |
| CN108303180B true CN108303180B (en) | 2020-05-29 |
Family
ID=62847685
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810253913.2A Active CN108303180B (en) | 2018-03-26 | 2018-03-26 | Vector light measuring device based on optical geometric transformation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108303180B (en) |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4842441B2 (en) * | 2001-01-24 | 2011-12-21 | 住友化学株式会社 | Convergent light polarization microscope apparatus and convergent light polarization microscope observation method |
| US10161797B2 (en) * | 2015-07-05 | 2018-12-25 | Purdue Research Foundation | Sub-millimeter real-time circular dichroism spectrometer with metasurfaces |
| CN105607267B (en) * | 2016-03-07 | 2017-11-17 | 东南大学 | A kind of device for generating salt free ligands needle-like light field |
| CN106225928A (en) * | 2016-07-08 | 2016-12-14 | 南京航空航天大学 | A kind of vector beam polarisation distribution detection apparatus and method |
-
2018
- 2018-03-26 CN CN201810253913.2A patent/CN108303180B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108303180A (en) | 2018-07-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7069265B2 (en) | Meta-surface, meta-surface manufacturing method and device | |
| CN101387519B (en) | Hollow photonic crystal fiber gyroscope | |
| JP5307558B2 (en) | Multi-core photonic bandgap fiber with inter-core coupling | |
| CN103424881B (en) | Fresnel prism phase retarder for double-rotation compensator ellipsometer | |
| CN107315221B (en) | A kind of thin footpath solid core polarization-maintaining photonic crystal fiber of double-layer structure | |
| Sheng et al. | Multiple super-resolution imaging in the second band of gradient lattice spacing photonic crystal flat lens | |
| CN102621099A (en) | Micro-nano fiber refractivity sensor and preparation method thereof | |
| CN104359472A (en) | Multi-loop type photonic band gap optical fiber gyroscope based on reflection | |
| CN112415284A (en) | Portable microwave electric field measuring device based on rydberg atoms | |
| Wolf et al. | Femtosecond writing of refractive index structures in multimode and multicore optical fibres | |
| Zhang et al. | Multi-focus optical fiber lens based on all-dielectric metasurface | |
| CN108303180B (en) | Vector light measuring device based on optical geometric transformation | |
| Wang et al. | Selective excitation of whispering-gallery modes and Fano resonance in a high-Q micro-capillary resonator with cleaned-up spectrum | |
| GB2386966A (en) | Optical element using one-dimensional photonic crystal and phase modulation unit | |
| Hao et al. | High-accuracy long distance alignment using single-mode optical fiber and phase plate | |
| CN103412371B (en) | Faraday rotary mirror capable of simultaneously carrying out polarization state conversion on multiple paths of optical signals | |
| CN102183735A (en) | Space magnetic field detector | |
| CN204854662U (en) | Laser fiber collimator | |
| Zhai et al. | Experimental Research on Temperature Sensing of Seawater Based on Three Interferometers Incorporated With Bow Tie Fiber | |
| Fang et al. | From Imbert–Fedorov shift to topologically spin-dependent walking off for highly confining fiber-guided twisted light | |
| CN104102016A (en) | Photonic crystal based polarizing beam splitter design method | |
| Dai et al. | Fabrication and optical properties of linear-corearray multicore fiber | |
| Qiu et al. | Using Mechanically-Induced Long-Period Fiber Gratings for OAM Modes Generation Based on Anti-Resonant Mechanisms in Ring-Core Fibers | |
| Liu et al. | Intermodal interference of LP01 and LP11 modes in panda fibers | |
| CN213632452U (en) | Double-core LPG temperature-magnetic field sensing probe based on magnetic fluid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |