CN111413812A - Polarization-independent optical fiber acousto-optic device - Google Patents
Polarization-independent optical fiber acousto-optic device Download PDFInfo
- Publication number
- CN111413812A CN111413812A CN202010393915.9A CN202010393915A CN111413812A CN 111413812 A CN111413812 A CN 111413812A CN 202010393915 A CN202010393915 A CN 202010393915A CN 111413812 A CN111413812 A CN 111413812A
- Authority
- CN
- China
- Prior art keywords
- acousto
- fiber
- light
- light splitting
- optic
- 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.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/11—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on acousto-optical elements, e.g. using variable diffraction by sound or like mechanical waves
- G02F1/125—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on acousto-optical elements, e.g. using variable diffraction by sound or like mechanical waves in an optical waveguide structure
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/11—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on acousto-optical elements, e.g. using variable diffraction by sound or like mechanical waves
Abstract
The invention discloses a polarization-independent fiber acousto-optic device, which comprises a single-mode fiber, a first fiber lens, a first beam splitter crystal, a first 1/2 wave plate, an acousto-optic medium, a second 1/2 wave plate, a second beam splitter crystal, a second fiber lens and an output fiber, wherein: the output end of the single-mode fiber is connected with the first fiber lens, the output end of the first fiber lens is aligned to the incident surface of the first light splitting crystal, the emergent surface of the first light splitting crystal is pasted with a first 1/2 wave plate, the emergent surface of the first light splitting crystal is aligned to the input end of the acousto-optic medium, the output end of the acousto-optic medium is aligned to the incident surface of the second light splitting crystal, the incident surface of the second light splitting crystal is pasted with a second 1/2 wave plate, the emergent surface of the second light splitting crystal is aligned to the input end of the second fiber lens, and the output end of the second fiber lens is connected with the input end of the output fiber. The invention widens the polarization selective acousto-optic dielectric material, and avoids the generation of polarization-related loss of the prior non-polarization-maintaining fiber acousto-optic device.
Description
Technical Field
The invention relates to the field of optical fiber acousto-optic devices, in particular to a polarization-independent optical fiber acousto-optic device.
Background
The fiber acousto-optic device has the advantages of low insertion loss, quick response time, compact structure, no moving part and the like, and is widely applied to the fields of laser processing and fiber sensing.
Most of acousto-optic medium materials used by the optical fiber acousto-optic device have polarization selectivity to input light, on one hand, for some materials, only linearly polarized light (horizontal or vertical) in a certain specific direction can generate acousto-optic interaction effect; on the other hand, the acousto-optic dielectric material is mostly a birefringent crystal, and the refractive indexes corresponding to different polarization states (horizontal or vertical) are different, so that the acousto-optic merit value M is caused2The difference (related to refractive index) between the two refractive indexes shows that the diffraction efficiency of the acousto-optic crystal is different under the same working condition, which is as follows:
wherein η is the diffraction efficiency, M2The material acousto-optic merit value of the acousto-optic medium.
For the reasons, the application of the non-polarization-maintaining optical fiber acousto-optic device has the following problems that on one hand, acousto-optic dielectric materials with two polarization states capable of generating acousto-optic interaction effect are required to be selected, so that the selection space is limited, and a plurality of excellent acousto-optic dielectric materials cannot be used; on the other hand, the available acousto-optic dielectric material generates polarization-dependent loss in practical use due to different diffraction efficiencies corresponding to different polarization states.
Therefore, how to widen the selection range of acousto-optic dielectric materials in the fiber acousto-optic device and reduce the polarization dependent loss generated in use becomes a problem which needs to be solved by the technical personnel in the field.
Disclosure of Invention
Aiming at the defects in the prior art, the problems to be solved by the invention are as follows: the selection range of acousto-optic dielectric materials in the fiber acousto-optic device is widened, and the polarization-dependent loss generated in use is reduced.
The invention adopts the following technical scheme:
a polarization-independent fiber acousto-optic device comprises a single-mode fiber, a first fiber lens, a first light splitting crystal, a first 1/2 wave plate, an acousto-optic medium, a second 1/2 wave plate, a second light splitting crystal, a second fiber lens and an output fiber, wherein: the output end of the single-mode fiber is connected with the first fiber lens, the output end of the first fiber lens is aligned to the incident surface of the first light splitting crystal, the emergent surface of the first light splitting crystal is pasted with a first 1/2 wave plate, the emergent surface of the first light splitting crystal is aligned to the input end of the acousto-optic medium, the output end of the acousto-optic medium is aligned to the incident surface of the second light splitting crystal, the incident surface of the second light splitting crystal is pasted with a second 1/2 wave plate, the emergent surface of the second light splitting crystal is aligned to the input end of the second fiber lens, and the output end of the second fiber lens is connected with the input end of the output fiber.
Preferably, the acousto-optic medium is connected to an impedance matching network.
Preferably, the width of the sound passing surface electrode of the acousto-optic medium is greater than or equal to the sum of the diameters of the two emergent light spots and the separation distance.
Preferably, the first light splitting crystal is used for converting the light beam output by the first fiber lens into o light and e light which are parallel to each other, and the separation distance L of the o light and the e light is larger than the emergent spot diameter d0 of the light beam output by the first fiber lens.
Preferably, the paste positions of the first 1/2 wave plate and the first 1/2 wave plate are determined based on the polarization selectivity of the acousto-optic medium.
In summary, the present invention discloses a polarization-independent fiber acousto-optic device, which includes a single-mode fiber, a first fiber lens, a first beam splitter crystal, a first 1/2 wave plate, an acousto-optic medium, a second 1/2 wave plate, a second beam splitter crystal, a second fiber lens, and an output fiber, wherein: the output end of the single-mode fiber is connected with the first fiber lens, the output end of the first fiber lens is aligned to the incident surface of the first light splitting crystal, the emergent surface of the first light splitting crystal is pasted with a first 1/2 wave plate, the emergent surface of the first light splitting crystal is aligned to the input end of the acousto-optic medium, the output end of the acousto-optic medium is aligned to the incident surface of the second light splitting crystal, the incident surface of the second light splitting crystal is pasted with a second 1/2 wave plate, the emergent surface of the second light splitting crystal is aligned to the input end of the second fiber lens, and the output end of the second fiber lens is connected with the input end of the output fiber. The invention widens the polarization selective acousto-optic dielectric material, and avoids the generation of polarization-related loss of the prior non-polarization-maintaining fiber acousto-optic device.
Drawings
For purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made in detail to the present application as illustrated in the accompanying drawings, in which:
FIG. 1 is a block diagram of a polarization independent fiber acousto-optic device according to an embodiment of the present invention;
FIG. 2 is a diagram of an optical path of an embodiment of a polarization independent fiber acousto-optic device according to the present disclosure.
Description of reference numerals: the optical fiber comprises a single-mode optical fiber 1, a first fiber lens 2, a first light splitting crystal 3, a first 1/2 wave plate 4, an acousto-optic medium 5, a second 1/2 wave plate 41, a second light splitting crystal 31, a second fiber lens 21, an output optical fiber 11, an incidence module 7 and an emergence module 71.
Detailed Description
The present application will now be described in further detail with reference to the accompanying drawings.
The invention discloses a polarization-independent fiber acousto-optic device, which comprises a single-mode fiber, a first fiber lens, a first beam splitter crystal, a first 1/2 wave plate, an acousto-optic medium, a second 1/2 wave plate, a second beam splitter crystal, a second fiber lens and an output fiber, wherein: the output end of the single-mode fiber is connected with the first fiber lens, the output end of the first fiber lens is aligned to the incident surface of the first light splitting crystal, the emergent surface of the first light splitting crystal is pasted with a first 1/2 wave plate, the emergent surface of the first light splitting crystal is aligned to the input end of the acousto-optic medium, the output end of the acousto-optic medium is aligned to the incident surface of the second light splitting crystal, the incident surface of the second light splitting crystal is pasted with a second 1/2 wave plate, the emergent surface of the second light splitting crystal is aligned to the input end of the second fiber lens, and the output end of the second fiber lens is connected with the input end of the output fiber.
In the invention, the first 1/2 wave plate is arranged corresponding to one emergent light beam of the first light splitting crystal, and the second 1/2 wave plate is arranged corresponding to one incident light beam of the second light splitting crystal.
The input light enters a first optical fiber lens through a single-mode optical fiber, the input light enters a first light splitting crystal after being collimated, the first light splitting crystal converts light beams into o light (vertical polarization state) and e light (horizontal polarization state) which are parallel to each other, the separation distance L of the o light and the e light is determined by the length D of the first light splitting crystal, a first 1/2 wave plate is pasted on one side of the emergent surface of the first light splitting crystal after the light splitting, one light beam is directly emitted, the other light beam is emitted through a first 1/2 wave plate, the emergent light is converted into two beams of o light or two beams of e light, the emergent light generates diffracted light after the sound-light interaction with an acousto-optic medium, the other light beam directly emits into a second light splitting crystal through a 1/2 wave plate, the other light beam enters a second optical fiber lens after being synthesized into one light beam through the second light splitting crystal, and the light beam is output through an output optical fiber.
When passing through the 1/2 wave plate, the vibration plane of the emergent light rotates 2 theta relative to the vibration plane of the incident light, the theta is the angle between the vibration plane of the incident light and the optical axis on the surface of the 1/2 wave plate, that is, when a plane polarized light passes through the 1/2 wave plate, the emergent light is still plane polarized light, but the vibration plane of the polarized light rotates a certain angle (2 theta), and the rotation angle is only determined by the angle theta between the vibration plane of the incident light and the optical axis of the 1/2 wave plate, therefore, twice the vibration plane of the 1/2 wave plate and the incident light is equal to the angle difference between o light and e light. Therefore, in the present invention, after the first dichroic crystal splits the light beam into o light and e light, the o light or the e light enters the first 1/2 wave plate (the first 1/2 wave plate is attached to the exit surface of the first dichroic crystal and rotates according to the position where the o light or the e light exits), and becomes the e light or the o light, which is then incident on the acousto-optic medium. Because the incident lights of the acousto-optic medium are e light or o light, only polarized light in one direction needs to be considered, and the range of the selectable acousto-optic medium is widened. In addition, because only one polarization state exists, different acousto-optic merit values cannot be caused, and polarization-dependent loss cannot be generated.
In summary, the invention discloses a polarization-independent fiber acousto-optic device, which widens the application field of polarization-selective acousto-optic dielectric materials and avoids the generation of polarization-dependent loss of the existing non-polarization-maintaining fiber acousto-optic device.
In specific implementation, the acousto-optic medium is connected with an impedance matching network.
Thus, the electroacoustic conversion can be realized better.
In specific implementation, the width of the surface electrode of the sound-passing surface of the acousto-optic medium is larger than or equal to the sum of the diameters and the separation distances of the two emergent light spots.
The acousto-optic medium is a cuboid, as shown in fig. 2, one surface is a sound through surface, and the other two surfaces are light through surfaces. In fig. 2, d represents the relative position of incident light.
In specific implementation, the first light splitting crystal is used for converting the light beam output by the first fiber lens into o light and e light which are parallel to each other, and the separation distance L between the o light and the e light is larger than the emergent spot diameter d0 of the light beam output by the first fiber lens.
If the separation distance is not enough, the light beams are overlapped, emergent light cannot be two complete o light beams or e light beams, and the preset effect cannot be achieved, so that the separation distance L of the o light beam and the e light beam is set to be larger than the emergent light spot diameter d0 of the light beam output by the first fiber lens.
In specific implementation, the pasting positions of the first 1/2 wave plate and the first 1/2 wave plate are determined based on the polarization selectivity of the acousto-optic medium.
The acousto-optic dielectric material has selectivity to polarized light, and there are several cases:
the incident light is o light, and the o light is diffracted;
the incident light is e light, and the e light is diffracted;
the incident light is o light, and e light is diffracted;
the incident light is e light, and o light is diffracted;
the principle of selection is that the incident light is selected to be a polarization state with a high acousto-optic figure of merit (some materials only have a single polarization direction to have an effect) or a polarization state light which needs to be used actually relative to the light passing direction of the acousto-optic dielectric material, and the bonding position of the wave plate is selected according to the actual situation of the diffracted light.
The polarization-independent fiber acousto-optic device disclosed by the invention can be obtained by the following steps:
(1) assembling an acousto-optic medium and debugging to a required working state through an impedance matching network;
(2) the light path is connected, a first 1/2 wave plate and a second 1/2 wave plate are bonded, the positions and angles of the first light splitting crystal and the second light splitting crystal are adjusted (the positions and angles can also be integrally adjusted after the first light splitting crystal and the second light splitting crystal are packaged), so that input light is two beams of o light or e light relative to the light passing surface of the acousto-optic dielectric material, emergent light of the first light splitting crystal and the second light splitting crystal is selected according to the acousto-optic dielectric material, and the modes of ① o light-o light, ② e light-e light, ③ o light-e light, ④ e light-o light exist;
and (3) adopting rotation adjustment to call out o light and e light in the step (2).
(3) Applying an RF signal to the acousto-optic medium, and integrally adjusting the position angle of the incident module until the diffracted light is strongest;
and (4) adjusting the deflection angle and the pitch angle of the light transmission direction of the acousto-optic medium in the step (3) to generate diffraction.
(4) And receiving the diffracted light through the emergent module, and solidifying the positions of the incident module and the emergent module.
Finally, it is noted that the above-mentioned embodiments illustrate rather than limit the invention, and that, while the application has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the application as defined by the appended claims.
Claims (5)
1. The polarization-independent fiber acousto-optic device is characterized by comprising a single-mode fiber, a first fiber lens, a first light splitting crystal, a first 1/2 wave plate, an acousto-optic medium, a second 1/2 wave plate, a second light splitting crystal, a second fiber lens and an output fiber, wherein: the output end of the single-mode fiber is connected with the first fiber lens, the output end of the first fiber lens is aligned to the incident surface of the first light splitting crystal, the emergent surface of the first light splitting crystal is pasted with a first 1/2 wave plate, the emergent surface of the first light splitting crystal is aligned to the input end of the acousto-optic medium, the output end of the acousto-optic medium is aligned to the incident surface of the second light splitting crystal, the incident surface of the second light splitting crystal is pasted with a second 1/2 wave plate, the emergent surface of the second light splitting crystal is aligned to the input end of the second fiber lens, and the output end of the second fiber lens is connected with the input end of the output fiber.
2. The polarization independent fiber acousto-optic device of claim 1, wherein the acousto-optic medium is connected to an impedance matching network.
3. The polarization independent fiber acousto-optic device of claim 1 wherein the acousto-optic medium has a pass surface electrode width greater than or equal to the sum of the diameter and separation distance of the two excident spots.
4. The polarization independent fiber acousto-optic device of claim 1 wherein the first beam splitting crystal is configured to convert the beam output by the first fiber lens into o and e parallel to each other, the o and e light being separated by a distance L that is greater than the exit spot diameter d0 of the beam output by the first fiber lens.
5. The polarization independent fiber acousto-optic device of claim 1, wherein the attachment locations of the first 1/2 wave plate and the first 1/2 wave plate are determined based on the polarization selectivity of the acousto-optic medium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010393915.9A CN111413812A (en) | 2020-05-11 | 2020-05-11 | Polarization-independent optical fiber acousto-optic device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010393915.9A CN111413812A (en) | 2020-05-11 | 2020-05-11 | Polarization-independent optical fiber acousto-optic device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111413812A true CN111413812A (en) | 2020-07-14 |
Family
ID=71493855
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010393915.9A Pending CN111413812A (en) | 2020-05-11 | 2020-05-11 | Polarization-independent optical fiber acousto-optic device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111413812A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114002866A (en) * | 2021-10-13 | 2022-02-01 | 光奥科技（武汉）有限公司 | Combined device of optical splitter and acousto-optic modulator |
-
2020
- 2020-05-11 CN CN202010393915.9A patent/CN111413812A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114002866A (en) * | 2021-10-13 | 2022-02-01 | 光奥科技（武汉）有限公司 | Combined device of optical splitter and acousto-optic modulator |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11726309B2 (en) | Illumination system for STED optical microscope and STED optical microscope | |
| US6529307B1 (en) | Selective intensity modulation of channels in a multiplexed optical communication system | |
| US8873898B2 (en) | Polarization independent wavelength converter and polarization independent wavelength conversion method | |
| CN100576666C (en) | High power light beam coupling semiconductor laser | |
| CN112235050B (en) | Single-optical-fiber bidirectional transmitting-receiving device and optical fiber communication system | |
| US20210294037A1 (en) | Single-ended output circulator | |
| CN111413812A (en) | Polarization-independent optical fiber acousto-optic device | |
| JPH0262173B2 (en) | ||
| CN211698500U (en) | Polarization-independent optical fiber acousto-optic device | |
| JPS63194223A (en) | Signal source package for optical communication | |
| JPH11202263A (en) | Depolarizer and optical transmission/reception module provided with the same | |
| CN111630948B (en) | Optical fiber coupling input and output acousto-optic device | |
| CN111562689A (en) | Broadband acousto-optic frequency shift system | |
| CN218728159U (en) | Light splitting isolator | |
| CN111367022A (en) | Compact optical device | |
| CN111799645B (en) | Chirp pulse compression synthesis system and application method thereof | |
| CN114069377B (en) | Mode control system based on acousto-optic device | |
| CN2593219Y (en) | Efficient high-power pulse laser polarizing apparatus | |
| CN216526617U (en) | Variable optical attenuator and communication equipment | |
| CN217156871U (en) | Mixed light-splitting detection device | |
| CN219610994U (en) | Light source device and module | |
| WO2022118790A1 (en) | Optical module | |
| CN215728933U (en) | Multifunctional optical path structure and integrated optical device | |
| JP2538569B2 (en) | Acousto-optic switch | |
| US20020171921A1 (en) | Laser resonator with direction sensitive decoupling |
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 |