CN209446465U - Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide - Google Patents
Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide Download PDFInfo
- Publication number
- CN209446465U CN209446465U CN201920058237.3U CN201920058237U CN209446465U CN 209446465 U CN209446465 U CN 209446465U CN 201920058237 U CN201920058237 U CN 201920058237U CN 209446465 U CN209446465 U CN 209446465U
- Authority
- CN
- China
- Prior art keywords
- wave guide
- medium wave
- prism
- determinand
- unsymmetrical metal
- 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.)
- Expired - Fee Related
Links
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The utility model discloses a kind of length scanning index sensors based on unsymmetrical metal cladding Medium Wave Guide, including wideband light source, the polarizer, prism, matching oil, substrate of glass, metallic film, determinand and spectrometer.Wideband light source issues the incident light of a wavelength range, becomes the linearly polarized light of specific direction after the polarizer, and perpendicular to prism surface incidence, coats Medium Wave Guide through prism-coupled irradiation unsymmetrical metal, reflected light in prism after projecting, in irradiation to spectrometer.By the measurement of reflectance spectrum, the excitation wavelength of corresponding guide mode resonance in unsymmetrical metal cladding Medium Wave Guide is determined, and then determine the refractive index of determinand.The utility model is using determinand as the ducting layer of unsymmetrical metal cladding Medium Wave Guide, take full advantage of the relationship between guide mode resonance wavelength change and determinand refractive index, realize highly sensitive refractive index sensing, with structure is simple and the advantage of high-sensitivity measurement, refractive index sensing field can be widely applied to.
Description
Technical field
The utility model belongs to index sensor field, relates to the use of unsymmetrical metal cladding Medium Wave Guide structure and carries out
The technical field of refractive index sensing measurement, in particular to the length scanning refractive index based on unsymmetrical metal cladding Medium Wave Guide pass
Sensor.
Background technique
Refractive index is an important optical properties parameter of substance, and the inside composition and ingredient of it and substance have directly
Connection.The detection of refractive index has a wide range of applications in the corresponding detection field such as biology, chemistry.Therefore, researcher
Propose many index sensors based on different sensing principles, wherein due to the close coupling property of surface plasma, it
Application in refractive index sensing field is also more and more, and the index sensor based on surface plasma mainly includes prism coupling
It closes and grating couples two ways, researcher has devised corresponding index sensor according to this, and realizes different spirits
The refractive index sensing of sensitivity measures, and still, these index sensors but still have certain deficiency, are mainly manifested in following several
A aspect:
(1) sensing scope is small: when carrying out refractive index sensing using prism coupling surface plasma resonance, the folding of determinand
The rate of penetrating is necessarily less than the refractive index of prism itself, therefore limits the sensing scope of refractometry.
(2) at high cost: when being sensed using grating-coupled surface plasma resonance, to need to consider the system of grating itself
Make technique, undoubtedly increases the cost of sensor production.
In addition, refractive index sensing measurement method mainly includes length scanning and angle scanning, and angle scanning is due to incidence
The continuous change of angle, therefore its refractive index sensing measurement efficiency is low and complicated for operation.
Utility model content
The purpose of this utility model is that making up the existing deficiency based on angle scanning index sensor, a kind of base is proposed
In the length scanning index sensor of unsymmetrical metal cladding Medium Wave Guide, to the angle scanning sensor using prism-coupled
Technological improvement is carried out, to realize easy to operate, low-cost highly sensitive refractive index sensing.
To achieve the above object, the technical scheme adopted by the utility model is
Based on unsymmetrical metal cladding Medium Wave Guide length scanning index sensor, including wideband light source, the polarizer,
Prism, matching oil, substrate of glass, metallic film, determinand and spectrometer, wherein what the wideband light source issued has one
The incident light of wavelength range, through the polarizer change polarization direction after, become TM or TE polarization linearly polarized light, and along perpendicular to
The direction of prism surface injects prism, and incident light is irradiated through prism-coupled to being made of metallic film, determinand and air
Unsymmetrical metal coats on Medium Wave Guide, and reflected light in irradiation to spectrometer, passes through the survey of reflectance spectrum after prism injection
Amount realizes the refractive index sensing of highly sensitive length scanning.
Wherein, there are guided wave mode in unsymmetrical metal cladding Medium Wave Guide, incident light is to excite the resonant wavelength of guided mode
When irradiation, incident laser energy will be coupled into the energy of guided mode in determinand, and the reflectance spectrum that spectrometer detection arrives will occur corresponding
The corresponding trough of guided mode can determine the resonant wavelength of guided mode under corresponding incident angle, in turn by the analysis to reflectance spectrum
The correlation theory that Medium Wave Guide is coated by unsymmetrical metal, is calculated and determined the refractive index of determinand, can be realized highly sensitive
The refractive index sensing of degree.
Wherein, the unsymmetrical metal coats Medium Wave Guide, is constitute three layers of determinand and air by metallic film
Structure, metallic film and air are used as the clad of cladding determinand.
Wherein, the incident light of different wave length is issued from wideband light source, changes polarization direction through the polarizer, by prism-coupled spoke
Unsymmetrical metal cladding Medium Wave Guide is shone, reflected light in prism after projecting, by spectrometer measurement reflectance spectrum.
Wherein, the light that different wave length is issued by wideband light source, it is incident along the direction perpendicular to prism surface, it ensure that institute
There is incident light with same incident angle irradiation unsymmetrical metal cladding Medium Wave Guide, so as to avoid due to caused by prism dispersion
The problem of light of different wave length is with different angle irradiation unsymmetrical metal cladding Medium Wave Guide, while ensure that the real-time of measurement
And accuracy.
The principles of the present invention are: the length scanning refractive index sensing based on unsymmetrical metal cladding Medium Wave Guide
Device, including wideband light source, the polarizer, prism, matching oil, substrate of glass, metallic film, determinand, spectrometer, wherein described
Wideband light source issue different wave length incident light, by the polarizer change polarization direction after, become TM or TE polarization linear polarization
Light, after refraction by prism, irradiation to unsymmetrical metal coats Medium Wave Guide, and reflected light is projected from prism, anti-by spectrometer measurement
Spectrum is penetrated, to determine guided wave mode present in waveguide by the resonant wavelength measured, and then determines the refractive index of determinand,
Realize highly sensitive refractive index sensing easy to operate.
Wherein, the wideband light source issues the incident light of different wave length, the excitation light source as excitation guide mode resonance.
Wherein, the polarizer, for changing by wideband light source issue natural light polarization direction, become TM or
The linearly polarized light of TE polarization.
Wherein, the prism, for coupling the guided wave mode in excitation unsymmetrical metal cladding Medium Wave Guide.
Wherein, the matching oil, for bonding prism and substrate of glass.
Wherein, the metallic film is deposited by electron beam evaporation onto substrate of glass, and as unsymmetrical metal packet
Cover the metal carbonyl coat in Medium Wave Guide structure.
Wherein, the determinand, as the ducting layer in unsymmetrical metal cladding Medium Wave Guide.
Wherein, the spectrometer, the measurement for reflectance spectrum.
Wherein, the wideband light source issues the natural light of a wavelength range, after the polarizer changes polarization direction, at
After the linearly polarized light polarized for TM or TE, is injected perpendicular to prism surface, both ensure that the incident light of all wavelengths can continue to
It propagates in the same direction, in turn ensures that the light of each wavelength coats Medium Wave Guide with same angle irradiation to unsymmetrical metal, and anti-
It penetrates light to be also perpendicularly to after prism surface projects, irradiation is on spectrometer, to realize the reflective spectral measure of length scanning.
The utility model is had following excellent based on the length scanning index sensor of unsymmetrical metal cladding Medium Wave Guide
Point:
(1) highly sensitive: there are guided mode, one timing of incident angle, different guided modes in unsymmetrical metal cladding Medium Wave Guide
The corresponding different excitation wavelength of resonance can be realized by the relationship of resonant wavelength and determinand refractive index using each guided mode
Highly sensitive refractive index sensing measurement.
(2) structure is simple and convenient to operate: in measurement, wideband light source, the polarizer, prism, unsymmetrical metal coat medium wave
Lead, the spatial position of spectrometer it is constant, only by using wideband light source issue different wave length incident light, both ensure that the sensing
The stability of device, and realize the reflective spectral measure of length scanning.Therefore, simply and easy to operate dual excellent with structure
Gesture.
(3) strong flexibility: due under incidence angles degree, refractive index sensing characteristic difference, therefore in actual measurement,
The prism and wideband light source of different angle can be selected according to actual needs.
Detailed description of the invention
Fig. 1 is length scanning index sensor signal of the utility model based on unsymmetrical metal cladding Medium Wave Guide
Figure；
Fig. 2 be incident angle be 45 ° when, determinand ranges of indices of refraction be the corresponding reflectance spectrum figure of 1.30-1.40；
Fig. 3 is the function relation figure between resonant wavelength corresponding to the reflectance spectrum figure of Fig. 2 and determinand refractive index；
Fig. 4 is the functional relation between the quality factor of spectral line corresponding to the reflectance spectrum figure of Fig. 2 and determinand refractive index
Figure；
Fig. 5 be incident angle be 60 ° when, determinand ranges of indices of refraction be the corresponding reflectance spectrum figure of 1.30-1.40；
Fig. 6 is the function relation figure between resonant wavelength corresponding to the reflectance spectrum figure of Fig. 5 and determinand refractive index；
Fig. 7 is the functional relation between the quality factor of spectral line corresponding to the reflectance spectrum figure of Fig. 5 and determinand refractive index
Figure.
In Fig. 1: 1 is wideband light source, and 2 be the polarizer, and 3 be prism, and 4 be matching oil, and 5 be substrate of glass, and 6 be metal foil
Film, 7 be determinand, and 8 be spectrometer.
Specific embodiment
The utility model is further described in detail with reference to the accompanying drawings and detailed description, identical mark in attached drawing
Number always show identical component.
Embodiment 1
Length scanning refractive index sensing schematic diagram based on unsymmetrical metal cladding Medium Wave Guide shown in referring to Fig.1, packet
Include wideband light source 1, the polarizer 2, prism 3, matching oil 4, substrate of glass 5, metallic film 6, determinand 7, spectrometer 8, in which: wide
Band light source 1, issues the incident light of a wavelength range, as the excitation light source for exciting related guided wave mode.
The polarizer 2 changes the polarization direction that incidence natural lights are issued by wideband light source 1, becomes TM or TE polarization
Linearly polarized light.
Prism 3, for coupling the guided wave mode in excitation unsymmetrical metal cladding Medium Wave Guide.
Matching oil 4, for bonding prism 3 and substrate of glass 5.
Substrate of glass 5, thickness are about 1mm, and as substrate, metallic film 6 is deposited by electron beam evaporation to substrate of glass 5
On.
Metallic film 6, the golden film that thickness is about 50nm, as the metal packet in unsymmetrical metal cladding Medium Wave Guide structure
Coating.
Determinand 7, thickness are about 500nm, as the ducting layer in unsymmetrical metal cladding Medium Wave Guide structure.
Spectrometer 9 is used as the measurement of reflectance spectrum.
Wideband light source 1, which issues the incident light that wavelength is 600~1000nm, becomes TM after the polarizer 2 changes polarization direction
The linearly polarized light of polarization, and injected perpendicular to (the selecting isosceles right-angle prism) surface of prism 3, it is arrived with 45 ° of incidence angle irradiation asymmetric
On metallic cover Medium Wave Guide, reflected light is after the injection of prism 3, and in irradiation to spectrometer 8, reflectance spectrum is as shown in Figure 2.Reference
Reflectance spectrum Fig. 2 that incident angle is 45 ° can calculate excitation TM0Corresponding incident wavelength when guide mode resonance, quality factor with to
The function relation figure between object refractive index is surveyed, it is as shown in Figure 3 and Figure 4 respectively.Wherein, incident wavelength and determinand reflect in Fig. 3
The sensitivity when slope (1339nm/RIU) of functional relation is 45° angle incidence between rate, the quality factor of sensor in Fig. 4
It is 85.0~102.7RIU in determinand 1.30~1.40 range of refractive index-1。
Embodiment 2
The issued wave-length coverage of wideband light source 1 is the incident light of 600~2000nm, after the polarizer 2 changes polarization direction,
As the linearly polarized light of TM polarization, and perpendicular to the incidence of prism 3 (selecting equilateral prism) surface, arrived with 60 ° of incidence angle irradiation non-
On symmetrical metal-cladding optical waveguide, reflectance spectrum excites corresponding TM as shown in figure 5, calculating it0The wavelength of guide mode resonance, quality
Function relation figure such as Fig. 6 between factor and determinand refractive index, shown in Fig. 7.Other structures are the same as embodiment 1.Wherein, in Fig. 6
It is sensitive when the slope (7724.9nm/RIU) of functional relation is the incidence of the angle 60o between incident wavelength and determinand refractive index
It spends, the quality factor of sensor are 72.1~92.3RIU in determinand 1.30~1.40 range of refractive index in Fig. 7-1。
The measurement of reflectance spectrum and the calculating of corresponding sensing characteristics when being respectively 45 ° and 60 ° by incident angle, can be very
It is apparent from resonant wavelength and red shift occurs with the increase of determinand refractive index, and the trend of linear increase is presented, illustrate that its is right
The stability of sensitivity when refractive index being answered to detect, also, for different incidence angles, sensing characteristics sensitivity, quality factor
Difference, therefore in actual refractive index measurement, it can be required according to specific, select different incidence angle and broadband light
Thus source also shows the flexibility of this index sensor.
Illustrate that it is non-that the utility model is based in conjunction with the electromagnetic theory of unsymmetrical metal cladding Medium Wave Guide further below
The principle of the length scanning index sensor of symmetrical metal-cladding optical waveguide:
Fig. 1 is the light path schematic diagram of the length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide.It is wide
The incident light of a wavelength range is issued with light source 1, substrate of glass 5, matching oil 4 and prism 3 are the materials of identical refractive index, if
It is ng, the refractive index of metallic film 6 is nm, determinand 7 with a thickness of da, the air of infinite thickness coats to be measured as clad
Object 7 coats Medium Wave Guide based on this unsymmetrical metal as composed by metallic film 6, determinand 7 and air three-decker,
The reflective spectral measure that length scanning is completed by spectrometer 8, passes through the analysis and calculating to reflectance spectrum, it may be determined that thickness da
Determinand 7 under the conditions of, unsymmetrical metal coat Medium Wave Guide in incident angle θ0Corresponding resonant wavelength, and finally thus count
Calculate the refractive index n for acquiring determinand 7a。
Wideband light source 1 issues the incident light of a wavelength range, changes polarization direction through the polarizer 2, becomes TM polarization
After linearly polarized light, injected along the surface direction perpendicular to prism 3, with θ0Incidence angle irradiation to unsymmetrical metal coat medium wave
In leading.The waveguiding structure is there are TM guided wave mode, when meeting modal eigenvalue equation:
TM can be excited0Guided wave resonance；
Wherein, nair,nm,naRespectively air, the refractive index of metallic film 6 and determinand 7, k0=2 π/λ0For vacuum
The a length of λ of medium wave0Incident light wave vector.As excitation TM0When guided wave mode, β meets:
β=k0ngsinθ0
Wherein, ngFor prism 3, matching oil 4 and the common refractive index of substrate of glass 5.
By above theory analysis it is found that when wideband light source 1 exports the incident light of a wavelength range, through the polarizer 2
After changing polarization direction, become the linearly polarized light of TM polarization, and along the surface direction perpendicular to prism 3 with θ0Incidence angle irradiation
Unsymmetrical metal coats Medium Wave Guide, when the thickness d of determinand 7aEtc. parameters determine after, occur TM0Incidence wave when guide mode resonance
Long λ0Only rely upon the refractive index n of determinand 7a, therefore unsymmetrical metal can be based on by the utility model and coat Medium Wave Guide
Length scanning index sensor, measure the refractive index of determinand 7, realize highly sensitive refractive index sensing measurement.
What the utility model did not elaborated partly belongs to techniques well known.
Claims (5)
1. the length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide, which is characterized in that the sensor packet
Include wideband light source (1), the polarizer (2), prism (3), matching oil (4), substrate of glass (5), metallic film (6), determinand (7) and
Spectrometer (8), wherein the wideband light source (1) issues the incident light of a wavelength range, changes through the polarizer (2) and polarizes
Behind direction, become the linearly polarized light of TM or TE polarization, and perpendicular to the incidence of prism (3) surface, through prism (3) coupling irradiation to gold
Belong to film (6), on the unsymmetrical metal cladding Medium Wave Guide that determinand (7) and air are constituted, reflected light is projected from prism (3)
Afterwards, in irradiation to spectrometer (8), the refractive index sensing of length scanning is realized by the measurement of reflectance spectrum.
2. the length scanning index sensor according to claim 1 based on unsymmetrical metal cladding Medium Wave Guide,
It being characterized in that, there are guided wave modes in unsymmetrical metal cladding Medium Wave Guide, under conditions of incident angle is certain, wideband light source
(1) when the incident irradiance unsymmetrical metal issued coats Medium Wave Guide, the corresponding light for exciting related guide mode resonance in incident light
Energy will be coupled into the energy of the guided mode in determinand (7), and the light of other wavelength will be totally reflected, and therefore, spectrometer (8) will
Detecting the corresponding trough of the corresponding guided mode of reflectance spectrum appearance can determine that corresponding guided mode is total by the analysis to reflectance spectrum
Shake corresponding excitation wavelength, and then the correlation theory of Medium Wave Guide is coated by unsymmetrical metal, and determinand is calculated and determined
(7) refractive index carries out the method for resonant wavelength measurement, it can be achieved that highly sensitive refractive index by this fixed incident angle
Sensing.
3. the length scanning index sensor according to claim 1 based on unsymmetrical metal cladding Medium Wave Guide,
It is characterized in that, the unsymmetrical metal coats Medium Wave Guide, is by metallic film (6), determinand (7) and three layers of air composition
Structure, metallic film (6) and air are used as the clad of cladding determinand (7).
4. the length scanning index sensor according to claim 1 based on unsymmetrical metal cladding Medium Wave Guide,
It is characterized in that, the incident light of the capable of emitting wavelength range of wideband light source (1), changes polarization direction through the polarizer (2), by prism
(3) coupling irradiation coats Medium Wave Guide to unsymmetrical metal, after reflected light is projected from prism (3), is measured by spectrometer (8) anti-
Penetrate spectrum.
5. the length scanning index sensor according to claim 1 based on unsymmetrical metal cladding Medium Wave Guide,
It is characterized in that, under conditions of incident angle is certain, the incident light of different wave length is issued by wideband light source (1), through the polarizer
(2) after changing polarization direction, become the linearly polarized light of TM or TE polarization, inject prism along the direction perpendicular to prism (3) surface
(3), to ensure that the incident light of different wave length coats Medium Wave Guide with same angle irradiation unsymmetrical metal, and with same anti-
Firing angle is projected from prism (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920058237.3U CN209446465U (en) | 2019-01-14 | 2019-01-14 | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920058237.3U CN209446465U (en) | 2019-01-14 | 2019-01-14 | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209446465U true CN209446465U (en) | 2019-09-27 |
Family
ID=68018423
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920058237.3U Expired - Fee Related CN209446465U (en) | 2019-01-14 | 2019-01-14 | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209446465U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109444078A (en) * | 2019-01-14 | 2019-03-08 | 兰州理工大学 | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide |
| CN112945307A (en) * | 2021-02-05 | 2021-06-11 | 江西师范大学 | Double-parameter measuring method based on double-waveguide-cavity Fano resonance device |
-
2019
- 2019-01-14 CN CN201920058237.3U patent/CN209446465U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109444078A (en) * | 2019-01-14 | 2019-03-08 | 兰州理工大学 | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide |
| CN112945307A (en) * | 2021-02-05 | 2021-06-11 | 江西师范大学 | Double-parameter measuring method based on double-waveguide-cavity Fano resonance device |
| CN112945307B (en) * | 2021-02-05 | 2022-10-14 | 江西师范大学 | Double-parameter measuring method based on double-waveguide-cavity Fano resonance device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Melendez et al. | A commercial solution for surface plasmon sensing | |
| EP0929803B1 (en) | Optical sensor for detecting chemical substances dissolved or dispersed in water | |
| KR101052504B1 (en) | High Resolution Surface Plasmon Resonance Sensor and Sensor System Using It | |
| CN101477045B (en) | Glass prism SPR sensor detection system based on P polarized light | |
| GB2197065A (en) | Optical sensor device | |
| WO2012111001A2 (en) | Optical sensor with enhanced sensitivity | |
| CN107703103B (en) | ghSPR sensor for detecting refractive index and detection method | |
| CN209446465U (en) | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide | |
| Watad et al. | Spectropolarimetric surface plasmon resonance sensor and the selection of the best polarimetric function | |
| CN108613949B (en) | Angle scanning refractive index sensor based on asymmetric metal cladding dielectric waveguide | |
| Rodrigues et al. | Surface plasmon resonance sensing characteristics of thin copper and gold films in aqueous and gaseous interfaces | |
| CN109444078A (en) | Length scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide | |
| Qi et al. | Nanoporous leaky waveguide based chemical and biological sensors with broadband spectroscopy | |
| US20130120743A1 (en) | Integrated Surface Plasmon Resonance Sensor | |
| KR20100106082A (en) | Surface plasmon resonance optical sensor | |
| Gong et al. | Theoretical study on negative permittivity of the material producing sharp surface plasmon resonance dips | |
| CN208476778U (en) | Angle scanning index sensor based on unsymmetrical metal cladding Medium Wave Guide | |
| Perino et al. | Characterization of grating coupled surface plasmon polaritons using diffracted rays transmittance | |
| Rodrigues et al. | Surface plasmon resonance features of corrugatec copper and gold films: Grating mode operation with wavelength interrogation | |
| CN111928880B (en) | Mach-Zehnder interference optical fiber based on surface plasma effect and sensor thereof | |
| KR20160028564A (en) | Plasmonic sensor with multilayer thin film and nano-structures | |
| JP7210027B2 (en) | Sensor and sensor manufacturing method | |
| US9823192B1 (en) | Auto-calibration surface plasmon resonance biosensor | |
| CN209542450U (en) | A kind of high refractive index liquid measuring device based on surface plasma body resonant vibration | |
| Karabchevsky et al. | Techniques for signal analysis in surface plasmon resonance sensors |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20190927 Termination date: 20200114 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |