CN102684809A - Method for realizing dense wavelength division multiplexing (DWDM) by utilizing photonic crystal panel Fano resonance effect - Google Patents
Method for realizing dense wavelength division multiplexing (DWDM) by utilizing photonic crystal panel Fano resonance effect Download PDFInfo
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Abstract
The invention provides a method for realizing dense wavelength division multiplexing (DWDM) by utilizing photonic crystal panel Fano resonance effect, wherein a wavelength division multiplexing (WDM) optical path system comprises a first tuned laser, a beam splitter, a first coupling fiber, a collimating lens, a sample stage and a spectrum analyzer, wherein the first tuned laser, the beam splitter, the first coupling fiber, the collimating lens, the sample stage, a second coupling fiber and a second spectrum analyzer are positioned on a same main optical path, the sample stage can be rotated, a second tuned laser is positioned on one side of the beam splitter on the main optical path, the first spectrum analyzer is positioned on one side of the sample stage on the main optical path, a third coupling fiber is arranged between the first spectrum analyzer and the sample stage, the first tuned laser and the second tuned laser are used for generating two paths of monochromatic light which is coupled into the same single-mode fiber by the beam splitter and the first coupling fiber for oblique incidence on samples placed on the sample stage after collimation through the collimating lens, and transmitted light and reflected light are respectively coupled to the first spectrum analyzer and the second spectrum analyzer by the second coupling fiber and the third coupling fiber for spectrum analysis.
Description
Technical field
The present invention relates to optical communication technique, photon crystal wavelength division multiplex technology, optical filtering technology, photon integrated technology field, particularly a kind of method of utilizing photonic crystal panel Fano resonance effects to realize optically filtering realization OWDM.
Background technology
Wavelength-division multiplex technique is that the signal with different wave length closes ripple, realizes that on same optical fiber multiplex (MUX) transmits simultaneously.Wavelength division multiplexing/multiplexing device is parts the most key in the wavelength-division multiplex technique, and it converges to the signal of different wave length an optical fiber or from multiple signals, filter out certain wavelengths.In the wavelength-division multiplex system of practical application at present, mainly contain grating type light wavelength division multiplexing and deielectric-coating Filter Type light wavelength division multiplexing.Traditional grating multiplexer generally adopts balzed grating,, but it makes difficulty, the beam splitting system complex structure, and cost is high; Propositions such as Robert W.Johnson are submitted long multilayer silicon dioxide of paraplasia and titanium deoxid film in glass substrate, obtain the infiltration type narrow band filter of the reasonable specific wavelength of temperature stability.People such as bang mountain propose to utilize the photon crystal structure of one dimension to realize narrow band filter, to be applied to dense wave division multipurpose.But no matter be interfere type multilayer thin-film-filter type wavelength division multiplexer or 1-D photon crystal mode filter type wavelength division multiplexer, all need be on substrate the vapor deposition multilayer dielectric film, installation time is long, and the loss of device is directly proportional with the multiplexing number of channel with cost.
Fano resonance in the 2 D photon crystal flat board is a kind of scattering effect of resonance, specifically is the interference effect that produces by between mechanism of the resonance scattering in the photonic crystal panel and the background air.On through spectrum or reflectance spectrum, directly translate into asymmetrical curve shape, be the Fano resonance curve.Have reflectivity peak and transmissivity peak respectively in the resonance point both sides.As shown in Figure 4, utilize this Fano resonance effects of photonic crystal panel can realize the narrow band filter of reflection-type and the narrow band filter of transmission-type simultaneously.Through regulating the parameter of photonic crystal panel, live width and the spacing that can regulate filter.Only need one deck photonic crystal panel, simple in structure, make easily.Utilize these advantages, can the method for two paths of signals through reflection filter and transmission filtering be realized photonic crystal panel structure dense wave division multiplexer.
Summary of the invention
Main purpose of the present invention is to provide a kind of method of utilizing photonic crystal panel Fano resonance effects to realize dense wave division multipurpose, and it is to utilize photonic crystal panel Fano resonance effects to realize the method for wavelength division multiplexing.Through making clear of the relation of last Fano formant of spectrum and photonic crystal parameters, band structure, obtained near the Fano resonant wavelength, to have respectively the pattern of total reflectivity and total transmissivity rate.Two paths of signals light incides photonic crystal panel at a certain angle, respectively by total reflection and total transmissivity, spatially with two paths of signals light separately, thereby realizes multiplexed optical wave usefulness.Through regulating photonic crystal parameters, the channel that two-way centre wavelength is very near at interval separately can conveniently be applied to the multiplexing device in the close wavelength-division multiplex technology.
For achieving the above object, the invention provides a kind of OWDM light path system, this system comprises:
One first tuned laser, a beam splitter, one first coupled fiber 4, collimation lens, a sample stage and a spectroanalysis instrument; Said first tuned laser, beam splitter, first coupled fiber, collimating lens, sample stage, second coupled fiber and second spectroanalysis instrument are positioned on the same main optical path, and this sample stage is rotatable;
One second tuned laser is positioned at a side of beam splitter on the main optical path;
One first spectroanalysis instrument is positioned at a side of sample stage on the main optical path, and one the 3rd coupled fiber is arranged between said first spectroanalysis instrument and sample stage;
Wherein, Producing two-way monochromatic light by first tuned laser and second tuned laser is coupled in same the monomode fiber through beam splitter, first coupled fiber; Retread through the collimating lens collimation and to incide on the sample that is placed on sample stage; Respectively transmitted light and reflection optical coupler are incorporated into first spectroanalysis instrument and second spectroanalysis instrument by second coupled fiber and the 3rd coupled fiber, carry out spectrum analysis.
The present invention also provides a kind of method of utilizing photonic crystal panel Fano resonance effects to realize dense wave division multipurpose, and this method is to adopt aforesaid multiplexed optical wave to use light path system, and this method comprises the steps:
Step 1: get a sample, on sample, make the airport array, form the photonic crystal panel of tetragonal lattice or triangular crystal lattice silicon materials;
Step 2 a: sample is placed on the sample stage this sample stage angle rotatable;
Step 3: send a light beam by first tuned laser and second tuned laser, be coupled in same the monomode fiber, through inciding behind the collimating lens collimation on the sample that is placed on the sample stage via first beam splitter, first coupled fiber;
Step 4: respectively transmitted light and reflection optical coupler are incorporated in first spectroanalysis instrument and second spectroanalysis instrument by second coupled fiber and the 3rd coupled fiber;
Step 5: this first spectroanalysis instrument and second spectroanalysis instrument carry out spectrum analysis.
The present invention utilizes the dull and stereotyped Fano resonance effects of the 2 D photon crystal channel that two-way centre wavelength is very little at interval partial wave spatially, realizes multiplexed optical wave usefulness.Device architecture is simple, realizes low preparation cost easily with micro fabrication; Device size is little, can conveniently be applied to the integrated and wavelength division multiplex optical communications network of light.
Description of drawings
For making the object of the invention, technical scheme and advantage clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, to further explain of the present invention, wherein:
Fig. 1 is the dull and stereotyped dense wave division multiplexer spare structural representation of 2 D photon crystal of the present invention;
Fig. 2 is two path channels dense wave division multipurpose light path system sketch mapes of the present invention;
Fig. 3 is the laser composite wave spectrum afterwards that two-way tuned laser of the present invention produces.
Fig. 4 is that 2 D photon crystal flat board of the present invention is composed and reflectance spectrum seeing through of signal wavelength section when the miter angle oblique incidence;
The transmitted spectrum that Fig. 5 is gathered by first spectroanalysis instrument for the present invention.
The reflectance spectrum that Fig. 6 is gathered by second spectroanalysis instrument for the present invention.
Embodiment
See also Fig. 1 to shown in Figure 2, the present invention provides a kind of OWDM light path system, and this system comprises:
One first tuned laser 1, a beam splitter 3, one first coupled fiber 4, collimation lens 5, a sample stage 6 and a spectroanalysis instrument 10; Said first tuned laser 1, beam splitter 3, first coupled fiber 4, collimating lens 5, sample stage 6, second coupled fiber 7 and second spectroanalysis instrument 10 are positioned on the same main optical path, and this sample stage 6 is rotatable;
One second tuned laser 2 is positioned at a side of beam splitter 3 on the main optical path;
One first spectroanalysis instrument 9 is positioned at a side of sample stage 6 on the main optical path, between said first spectroanalysis instrument 9 and sample stage 6, one the 3rd coupled fiber 8 is arranged;
Wherein, Producing two-way monochromatic light by first tuned laser 1 and second tuned laser 2 is coupled in same the monomode fiber through beam splitter 3, first coupled fiber 4; Retread through collimating lens 5 collimations and to incide on the sample that is placed on sample stage 6; Respectively transmitted light and reflection optical coupler are incorporated into first spectroanalysis instrument 9 and second spectroanalysis instrument 10 by second coupled fiber 7 and the 3rd coupled fiber 8, carry out spectrum analysis.
Wherein this wavelength division multiplexing light path system works is at optical communicating waveband.
100 in the sample that wherein said photonic crystal panel wavelength-division multiplex system adopts just can be realized wavelength division multiplexing with one deck photonic crystal panel.
See also Fig. 1 to shown in Figure 6, the present invention also provides a kind of method of utilizing photonic crystal panel Fano resonance effects to realize dense wave division multipurpose, and this method is to adopt aforesaid multiplexed optical wave to use light path system, and this method comprises the steps:
Step 1: get a sample 100, on sample 100, make airport array 101, form the photonic crystal panel of tetragonal lattice or triangular crystal lattice silicon materials;
Step 2 a: sample 100 is placed on the sample stage 6 these sample stage 6 angle rotatables;
Step 3: send a light beam by first tuned laser 1 and second tuned laser 2; Be coupled in same the monomode fiber via first beam splitter 3, first coupled fiber 4; Behind collimating lens 5 collimations, incide on the sample that is placed on the sample stage 6; Wherein first tuned laser, 1 second tuned laser 2 is tuned lasers of communication band; It is said that behind collimating lens 5 collimations, to incide the incident light that is placed on the sample stage 6 be oblique incident ray; Said first tuned laser 1 and second tuned laser, 2 centre wavelengths are respectively photonic crystal panel and see through spectrum upward Fano resonance maximum reflectivity wavelength and maximum transmission rate wavelength, and the laser center wavelength that said first tuned laser 1 and second tuned laser 2 produce is at interval less than 1nm;
Step 4: respectively transmitted light and reflection optical coupler are incorporated in first spectroanalysis instrument 9 and second spectroanalysis instrument 10 by second coupled fiber 7 and the 3rd coupled fiber 8;
Step 5: this first spectroanalysis instrument 9 and second spectroanalysis instrument 10 carry out spectrum analysis.
The dull and stereotyped micro-nano processing method embodiment that adopts:
See also Fig. 1, the silicon based photon crystal of two-dimentional tetragonal lattice is dull and stereotyped to adopt micro-nano processing method processing to obtain.Step is following: the thick monocrystalline silicon 100 of 681nm of on earth silicon material 102, growing earlier, and going out diameter in 100 surface etch again is 510nm, and hole depth is 681nm, and the cycle is the tetragonal lattice photon crystal 1 01 of 851nm; The bottom layer silicon dioxide corrosion that to be carved with the big small size of photonic crystal pattern with NaOH at last obtains the individual layer photonic crystal panel.
Experimental system embodiment:
See also Fig. 2, the Fano resonance effects of employing photonic crystal panel provided by the invention realizes that the experimental system of light wave multiplexing method comprises:
One first tuned laser 1, a beam splitter 3, one first coupled fiber 4, collimation lens 5, a sample stage 6 and a spectroanalysis instrument 10; Said first tuned laser 1, beam splitter 3, first coupled fiber 4, collimating lens 5, sample stage 6, second coupled fiber 7 and second spectroanalysis instrument 10 are positioned on the same main optical path, and this sample stage 6 is rotatable;
One second tuned laser 2 is positioned at a side of beam splitter 3 on the main optical path;
One first spectroanalysis instrument 9 is positioned at a side of sample stage 6 on the main optical path, between said first spectroanalysis instrument 9 and sample stage 6, one the 3rd coupled fiber 8 is arranged;
See also Fig. 2 and Fig. 3; The flashlight that the present invention adopts is first tuned laser 1 and the generation of second tuned laser of 0.2nm by the pulsewidth that centre wavelength is respectively 1549nm and 1550nm; Closing ripple by beam splitter 3 through first coupled fiber 4 again is same light beam; It is as shown in Figure 3 to close the spectrum that obtains behind the ripple: transverse axis is a wavelength, and the longitudinal axis is normalized laser intensity.By the light of first coupled fiber 4 output again by collimating lens 5 collimations; With the sample surfaces of miter angle oblique incidence on sample stage 6; Transmitted light and reverberation are coupled to first spectroanalysis instrument 9 and second spectroanalysis instrument 10 respectively by second coupled fiber 7 and the 3rd coupled fiber 8, carry out spectrum analysis.
See also Fig. 4, to be the incident light wave that obtains of Theoretical Calculation shine the reflectance spectrum behind the sample on the sample stage 6 with miter angle to Fig. 4.Therefrom can see, be the flashlight of 1549nm for centre wavelength, reflects the byest force, and is the flashlight of 1550nm for centre wavelength, and transmission is the strongest.The strongest transmissivity and strong reflection rate are all near a hundred per cent.Sample is placed on the sample stage 6 of fine-tuning angle, can adjust incident angle of light through the gradient of regulating sample.
See also Fig. 4, Fig. 5 and Fig. 6; After inciding the sample on the sample stage 6 from the light (like Fig. 4) of collimating lens output;, obtain respectively by first spectroanalysis instrument 9 and second spectroanalysis instrument, 10 collection analysises through the light of sample reflection and transmission like transmitted spectrum and the reflectance spectrum shown in Fig. 5 and Fig. 6 distinguish.As can be seen from Figure 5; Closing spectrum (like Fig. 4) behind the ripple by first tuned laser 1 and second tuned laser 2, after the sample transmission on the sample stage 6, in transmission spectrum, to have only centre wavelength be the light of 1550nm; Have only the light of 1549nm in the reflectance spectrum after reflection, thereby realized wavelength division multiplexing.
The above; Only be embodiments of the invention; Be not that the present invention is done any pro forma restriction; Every according to technical spirit of the present invention to any simple modification, equivalent variations and modification that above embodiment did, all still belong within the technical scheme scope of the present invention, so protection scope of the present invention is when being as the criterion with claims.
Claims (8)
1. OWDM light path system, this system comprises:
One first tuned laser, a beam splitter, one first coupled fiber, collimation lens, a sample stage and a spectroanalysis instrument; Said first tuned laser, beam splitter, first coupled fiber, collimating lens, sample stage, second coupled fiber and second spectroanalysis instrument are positioned on the same main optical path, and this sample stage is rotatable;
One second tuned laser is positioned at a side of beam splitter on the main optical path;
One first spectroanalysis instrument is positioned at a side of sample stage on the main optical path, and one the 3rd coupled fiber is arranged between said first spectroanalysis instrument and sample stage;
Wherein, Producing two-way monochromatic light by first tuned laser and second tuned laser is coupled in same the monomode fiber through beam splitter, first coupled fiber; Retread through the collimating lens collimation and to incide on the sample that is placed on sample stage; Respectively transmitted light and reflection optical coupler are incorporated into first spectroanalysis instrument and second spectroanalysis instrument by second coupled fiber and the 3rd coupled fiber, carry out spectrum analysis.
2. OWDM light path system according to claim 1, wherein this wavelength division multiplexing light path system works is at optical communicating waveband.
3. OWDM light path system according to claim 1, the sample that wherein said photonic crystal panel wavelength-division multiplex system adopts only just can be realized wavelength division multiplexing with one deck photonic crystal panel.
4. method of utilizing photonic crystal panel Fano resonance effects to realize dense wave division multipurpose, this method is to adopt multiplexed optical wave as claimed in claim 1 to use light path system, this method comprises the steps:
Step 1: get a sample, on sample, make the airport array, form the photonic crystal panel of tetragonal lattice or triangular crystal lattice silicon materials;
Step 2 a: sample is placed on the sample stage this sample stage angle rotatable;
Step 3: send a light beam by first tuned laser and second tuned laser, be coupled in same the monomode fiber, through inciding behind the collimating lens collimation on the sample that is placed on the sample stage via first beam splitter, first coupled fiber;
Step 4: respectively transmitted light and reflection optical coupler are incorporated in first spectroanalysis instrument and second spectroanalysis instrument by second coupled fiber and the 3rd coupled fiber;
Step 5: this first spectroanalysis instrument and second spectroanalysis instrument carry out spectrum analysis.
5. the method for utilizing photonic crystal panel Fano resonance effects to realize intensive OWDM according to claim 4, wherein first tuned laser, second tuned laser is the tuned laser of communication band.
6. the method for utilizing photonic crystal panel Fano resonance effects to realize intensive OWDM according to claim 4, wherein behind the collimating lens collimation, inciding the incident light that is placed on the sample stage is oblique incident ray.
7. the method for utilizing photonic crystal panel Fano resonance effects to realize intensive OWDM according to claim 5, wherein said first tuned laser and the second tuned laser centre wavelength are respectively photonic crystal panel and see through spectrum upward Fano resonance maximum reflectivity wavelength and maximum transmission rate wavelength.
8. the method for utilizing photonic crystal panel Fano resonance effects to realize intensive OWDM according to claim 5, the laser center wavelength that wherein said first tuned laser and second tuned laser produce is at interval less than 1nm.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107703616A (en) * | 2016-08-08 | 2018-02-16 | 大连光耀辉科技有限公司 | Multi-channel laser output equipment and fluorescence microscope |
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| US20070024860A1 (en) * | 2005-08-01 | 2007-02-01 | Mitutoyo Corporation | Dual laser high precision interferometer |
| CN101866089A (en) * | 2010-05-19 | 2010-10-20 | 中国科学院半导体研究所 | Method for realizing optical switch by utilizing photonic crystal panel to conduct formant displacement |
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| CN107703616A (en) * | 2016-08-08 | 2018-02-16 | 大连光耀辉科技有限公司 | Multi-channel laser output equipment and fluorescence microscope |
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Application publication date: 20120919 |