CN105675545B - Highly sensitive strength investigation method based on self-interference type micro-resonant cavity photo-sensor - Google Patents
Highly sensitive strength investigation method based on self-interference type micro-resonant cavity photo-sensor Download PDFInfo
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- CN105675545B CN105675545B CN201610026981.6A CN201610026981A CN105675545B CN 105675545 B CN105675545 B CN 105675545B CN 201610026981 A CN201610026981 A CN 201610026981A CN 105675545 B CN105675545 B CN 105675545B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/45—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
- G01N21/45—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods
- G01N2021/458—Refractivity; Phase-affecting properties, e.g. optical path length using interferometric methods; using Schlieren methods using interferential sensor, e.g. sensor fibre, possibly on optical waveguide
Abstract
A kind of highly sensitive strength investigation method based on self-interference type micro-resonant cavity photo-sensor, radio-frequency spectrum, which possesses to lead with unicast, out is coupled to the similar frequency spectrum of micro-ring resonant cavity, which is the frequency spectrum for transmitting valley and having periodic distribution；Measured matter is covered on to the upper surface of optical detection arm waveguide, light is incident from one end of input waveguide, couples with micro-ring resonant cavity, then a part is coupled into micro-ring resonant cavity；Another part, which is emitted from the other end of input waveguide and passes through optical detection arm, enters output waveguide, a part of light is due to the coupling between output waveguide and micro-resonant cavity in this part, a part of light for being again coupled into micro-resonant cavity, and being coupled out in a part of light and micro-ring resonant cavity in this part is emitted after interferenceing from the output waveguide other end；Highly sensitive sensing can be realized in variation by testing resonance wave strong point intensity transmission.The present invention avoids requiring very high-precision frequency positioning under the premise of keeping high sensitivity, reduces cost of testing system.
Description
Technical field
The present invention relates to optical sensing field, especially a kind of Gao Ling based on self-interference type micro-resonant cavity photo-sensor
Sensitivity strength investigation method.
Background technique
In recent years, low cost, the demand of highly sensitive miniature transducer constantly increase, especially in biochemical preparation and
The substances context of detection such as toxic gas.It addresses that need, industry and academia have proposed and made many types
Sensor, wherein optical sensor is concerned in numerous type sensors with its minimum size and high sensitivity.
Many optical phenomenas such as, absorption, fluorescence, radiation and refraction etc. and many optical medium structures, such as optical fiber, photonic crystal, micro-
Annular resonant cavity, surface plasma and grating etc. are all used to open up novel sensor mechanism to obtain preferable sensing effect.
Optical sensor based on micro-ring resonant cavity has size small, high sensitivity and it is compatible with CMOS technology be easily integrated etc. it is excellent
Point is widely used in optical sensing field, when optical waveguide effective refractive index changes with target substance, micro-resonant cavity
Resonance wavelength is drifted about, thus by test this wave length shift can measure target substance concentration variation (document 1,
Mario,La.Notte,Benedetto Troia,Tommaso Muciaccia,Calo Edoardo Campanella,
Francesco De Leonardis and Vittoro M.N.Passaro,“Recent advances in gas and
chemical detection by vernier effect-based photonic sensors”,Sensors,V.14(3),
4831-4855 (2014), i.e. Mario, La.Notte, Benedetto Troia, Tommaso Muciaccia, Calo
Edoardo Campanella, Francesco De Leonardis and Vittoro M.N.Passaro " is imitated based on vernier
Progress of the optical sensor answered in gas and chemical probing ", sensor, V.14 (3), 4831-4855 (2014)).So
And the optical sensor based on micro-ring resonant cavity remains some the shortcomings that limiting its further development and application.For base
In the optical sensor of micro-ring resonant cavity, high sensitivity needs a sharp resonance spectrum, and detection limit depends on micro-loop
The Q factor of resonant cavity.This requires the transmission loss of device is low, to improve the requirement to device making technics.Subsequent section
The personnel of grinding propose the optical sensor based on cursor effect, to obtain high sensitivity and low detection limit.In fact,
Raising based on cursor effect sensitivity is derived solely from the reading method of vernier graduation, and physics intrinsic sensitivity does not obtain
A bit raising.Dai etc. proposes a kind of micro-ring resonant cavity that coupling is related to based on Mach-increasing Deccan, by measuring resonant wavelength
Movement, about 10 can be detected with higher sensitivity-6~10-5Effective refractive index variation.But in measurement variations in refractive index
Value is 10-6When, wavelength amount of movement is only 0.35pm, needs detection system of a high price (patent 1, ZL
200810060460.8).In patent (patent 1, ZL 200810060460.8), it was also proposed that measured in a certain fixed wave length
The method of transimission power measures the variation of refractive index, but the frequency spectrum actually generated due to method promise (Fano) effect is wide,
There are problems in practice, for example its measurement range is limited, the measurement linearity is very poor.Therefore, high detection accuracy is being kept
Under the premise of, it is necessary to new sensor mechanism is explored so that the detection cost of system is effectively reduced, such as is replaced originally with strength investigation
Wavelength measurement.
Summary of the invention
It is required when holding high sensitivity in order to overcome existing self-interference type micro-resonant cavity photo-sensor detection method very high
The frequency positioning of precision, the higher deficiency of cost of testing system, the present invention provide one kind under the premise of keeping high sensitivity
The height based on self-interference type micro-resonant cavity photo-sensor for avoiding requiring very high-precision frequency positioning, reducing cost of testing system
Sensitivity strength investigation method.
The technical solution adopted by the present invention to solve the technical problems is:
A kind of highly sensitive strength investigation method based on self-interference type micro-resonant cavity photo-sensor, realizes the micro- of the detection
Resonant cavity photo-sensor includes an input waveguide, a micro-ring resonant cavity, an output waveguide and an optical detection arm waveguide,
Input waveguide and output waveguide are coupled with micro-ring resonant cavity respectively, are placed in the two sides of micro-ring resonant cavity, and one end of input waveguide is
The light source incoming end of entire optical sensor；The other end of input waveguide and light are visited at the coupling of input waveguide and micro-ring resonant cavity
The input terminal of test arm waveguide is connected；The output end of optical detection arm waveguide and output at the coupling of output waveguide and micro-ring resonant cavity
One end of waveguide is connected, and the other end of output waveguide is transducing signal exit end；Out radio-frequency spectrum possess led with unicast be coupled to it is micro-
The similar frequency spectrum of annular resonant cavity, the transmission spectrum are the frequency spectrums for transmitting valley and having periodic distribution；
Detection method are as follows: measured matter is covered on to the upper surface of optical detection arm waveguide, light enters from one end of input waveguide
It penetrates, is coupled with micro-ring resonant cavity, then a part is coupled into micro-ring resonant cavity；The other end of the another part from input waveguide
It is emitted and passes through optical detection arm and enter output waveguide, a part of light is due to the coupling between output waveguide and micro-resonant cavity in this part
Cooperation is used, and is again coupled into micro-resonant cavity, and a part of light being coupled out in a part of light and micro-ring resonant cavity in this part
It is emitted after interference from the output waveguide other end；High sensitivity can be realized in variation by testing resonance wave strong point intensity transmission
Sensing.
Further, when measured matter refractive index changes, the optical path length of optical detection arm waveguide changes, not only
Resonance wavelength at transmission valley is drifted about, and the intensity for transmitting valley changes.
Technical concept of the invention are as follows: when optical detection arm waveguide length meets 0.75 times equal to micro-ring resonator length
When, the radio-frequency spectrum that goes out of the self-interference type micro-ring resonant cavity possesses to lead with unicast and is coupled to the similar frequency spectrum of micro-ring resonant cavity, the biography
Defeated spectrum is the frequency spectrum for transmitting valley and having periodic distribution.In the corresponding resonance wavelength of transmission valley, not only with the micro-ring resonant
The physical length of chamber is related, and long with the physics of the coefficient of coup and optical detection arm of input and output waveguide and micro-ring resonant cavity
It spends related.Equally, the size also coefficient of coup and optical detection with input and output waveguide and micro-ring resonant cavity of valley is transmitted
The physical length of arm is related.Therefore, when measured matter refractive index changes, the optical path length of optical detection arm waveguide becomes
Change, not only transmits the resonance wavelength at valley and drift about, but also the intensity for transmitting valley changes.By testing resonance wave
Highly sensitive sensing can be realized in the variation of strong point intensity transmission.
Beneficial effects of the present invention are mainly manifested in: so that the sensor is under the premise of keeping high detectivity,
It is only necessary to one high-precision ionization meter can be realized with the laser of frequency sweep, avoid sensors with auxiliary electrode in measurement frequency
Very high-precision frequency positioning is needed when rate is mobile, greatly reduces the cost of test macro.
Detailed description of the invention
Fig. 1 is self-interference type micro-ring resonant cavity optical sensor structural schematic diagram.
Fig. 2 is the radio-frequency spectrum out of self-interference type micro-ring resonant cavity.
Transmission paddy of the Fig. 3 at wavelength X=1552nm is with input and output waveguide and micro-ring resonant cavity coefficient of coup size
Variation.
Transmission paddy of the Fig. 4 at wavelength X=1552nm with optical detection arm waveguide optical path length minor change when and generate
Variation.
The normalization intensity transmission value that Fig. 5 transmits paddy at wavelength X=1552nm is micro- with optical detection arm waveguide optical path length
The curve of small variation.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.
Referring to Fig.1~Fig. 5, a kind of highly sensitive strength investigation method based on self-interference type micro-resonant cavity photo-sensor,
The micro-resonant cavity photo-sensor for realizing the detection includes the micro-ring resonant cavity 2, one of input waveguide 1, one 3 and of output waveguide
A piece optical detection arm waveguide 4, input waveguide 1 and output waveguide 3 are coupled with micro-ring resonant cavity 2 respectively, are placed in micro-ring resonant cavity 2
Two sides, one end of input waveguide 1 is the light source incoming end of entire optical sensor, in the coupling of input waveguide 1 and micro-ring resonant cavity 2
Place, the other end of input waveguide 1 is connected with the input terminal of optical detection arm waveguide 4, in the coupling of output waveguide 3 and micro-ring resonant cavity 2
At conjunction, one end of output waveguide 3 is connected with the output end of optical detection arm waveguide 4, and the other end of output waveguide 3 goes out for transducing signal
It penetrates end: going out radio-frequency spectrum and possess to lead with unicast to be coupled to the similar frequency spectrum of micro-ring resonant cavity, which is that transmission valley has week
The frequency spectrum of phase property distribution；
Detection method are as follows: measured matter is covered on to the upper surface of optical detection arm waveguide, light enters from one end of input waveguide
It penetrates, is coupled with micro-ring resonant cavity, then a part is coupled into micro-ring resonant cavity；The other end of the another part from input waveguide
It is emitted and passes through optical detection arm and enter output waveguide, a part of light is due to the coupling between output waveguide and micro-resonant cavity in this part
Cooperation is used, and is again coupled into micro-resonant cavity, and a part of light being coupled out in a part of light and micro-ring resonant cavity in this part
It is emitted after interference from the output waveguide other end；High sensitivity can be realized in variation by testing resonance wave strong point intensity transmission
Sensing.
Further, when measured matter refractive index changes, the optical path length of optical detection arm waveguide changes, not only
Resonance wavelength at transmission valley is drifted about, and the intensity for transmitting valley changes.
Example: self-interference type micro-ring resonant transducer in this example, R=30 μm of micro-loop radius, then the physics of micro-loop circumference is long
Spend LR=2 π R, the physical length of optical detection arm waveguide are LW=0.75LR+d.Fig. 2 is the radio frequency out of self-interference type micro-ring resonant cavity
Spectrum, d=0.004 μm at this time, effective refractive index neff=2.85, the coupled systemes of input waveguide and output waveguide and micro-ring resonant cavity
Number it is equal, be 0.5, in the sensor in all optical waveguides optical mode unit length loss factor α=0.01dB/cm.
From figure 2 it can be seen that the radio-frequency spectrum out of the self-interference type micro-ring resonant cavity, which possesses to lead with unicast, is coupled to micro-ring resonant cavity class
As frequency spectrum, the transmission spectrum be transmit valley have periodic distribution frequency spectrum.Fig. 3 is shown at wavelength X=1552nm
Paddy is transmitted with the variation of input and output waveguide and micro-ring resonant cavity coefficient of coup size.Fig. 4 is shown at wavelength X=1552nm
Transmission paddy with optical detection arm waveguide optical path length minor change when and the variation that generates.This shows corresponding in transmission valley
Resonance wavelength, it is not only related with the physical length of the micro-ring resonant cavity, but also the coupling with input and output waveguide and micro-ring resonant cavity
The physical length of collaboration number and optical detection arm is related.Equally, transmit valley size also with input and output waveguide and micro-loop
The coefficient of coup of resonant cavity and the physical length of optical detection arm are related.Fig. 5 is shown transmits paddy at wavelength X=1552nm
Intensity transmission value is normalized with the curve of optical path length minor change d.As can be seen from Figure in k=0.5,1nm < d <
The good linearity can be obtained when 2.5nm, measurement accuracy is about 0.1nm at this time, and corresponding variations in refractive index is about 10-6.Work as k
When=0.15,0.85, corresponding measurement range expands, but measurement accuracy declines.In k=0.9985, measurement range can expand
To 25nm, measurement accuracy falls to 1nm, and corresponding variations in refractive index is about 10-5。
Above-described embodiment is used to illustrate the present invention, rather than limits the invention, in spirit of the invention and
In scope of protection of the claims, to any modifications and changes that the present invention makes, protection scope of the present invention is both fallen within.
Claims (2)
1. a kind of highly sensitive strength investigation method based on self-interference type micro-resonant cavity photo-sensor, realizes the micro- humorous of the detection
The chamber optical sensor that shakes includes an input waveguide, a micro-ring resonant cavity, an output waveguide and an optical detection arm waveguide, defeated
Enter waveguide and output waveguide is coupled with micro-ring resonant cavity respectively, be placed in the two sides of micro-ring resonant cavity, one end of input waveguide is whole
The light source incoming end of a optical sensor；The other end of input waveguide and optical detection at the coupling of input waveguide and micro-ring resonant cavity
The input terminal of arm waveguide is connected；The output end and output wave of optical detection arm waveguide at the coupling of output waveguide and micro-ring resonant cavity
The one end led is connected, and the other end of output waveguide is transducing signal exit end；It is characterized by: radio-frequency spectrum possesses and leads with unicast out
It is coupled to the similar frequency spectrum of micro-ring resonant cavity, transmission spectrum is the frequency spectrum for transmitting valley and having periodic distribution；
Detection method are as follows: measured matter is covered on to the upper surface of optical detection arm waveguide, light is incident from one end of input waveguide, with
Micro-ring resonant cavity couples, then a part is coupled into micro-ring resonant cavity；Another part is emitted from the other end of input waveguide
And entering output waveguide by optical detection arm, a part of light is due to the coupling work between output waveguide and micro-resonant cavity in this part
With, it is again coupled into micro-resonant cavity, and a part of light being coupled out in a part of light and micro-ring resonant cavity in this part is relevant
It is emitted after relating to from the output waveguide other end；Highly sensitive biography can be realized in variation by testing resonance wave strong point intensity transmission
Sense.
2. as described in claim 1 based on the highly sensitive strength investigation method of self-interference type micro-resonant cavity photo-sensor,
Be characterized in that: when measured matter refractive index changes, the optical path length of optical detection arm waveguide changes, and not only transmits paddy
Resonance wavelength at value is drifted about, and the intensity for transmitting valley changes.
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| CN110554006B (en) * | 2019-09-04 | 2021-10-19 | 中国科学技术大学 | Multi-mode measurement method based on self-interference micro-ring resonant cavity optical sensor |
| CN110726689B (en) * | 2019-09-26 | 2022-01-11 | 宁波大学 | Micro-miniature spectral absorption type optical waveguide type mid-infrared gas sensor and application thereof |
| CN110849843A (en) * | 2019-11-06 | 2020-02-28 | 东南大学 | Silicon-based refractive index sensor based on cascading U-shaped waveguide nested micro-ring |
| US11448085B2 (en) * | 2019-11-11 | 2022-09-20 | Raytheon Technologies Corporation | Remote temperature measurement system for gas turbine engine |
| CN111721336A (en) * | 2020-03-09 | 2020-09-29 | 浙江工业大学 | Self-interference micro-ring resonant cavity sensing classification identification method based on supervised learning |
| CN113686367B (en) * | 2021-03-17 | 2023-12-29 | 广东工业大学 | Sensing structure based on optical fiber coupling induction transparency, manufacturing process and sensing device |
| CN113358589B (en) * | 2021-06-04 | 2022-06-28 | 中国人民解放军国防科技大学 | Atomic air chamber probe device with micro-ring resonant cavity |
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| EP2952942A1 (en) * | 2014-06-04 | 2015-12-09 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO | Photonic integrated circuit |
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| DE59109246D1 (en) * | 1990-05-03 | 2003-04-03 | Hoffmann La Roche | Micro-optical sensor |
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| CN100593711C (en) * | 2008-04-11 | 2010-03-10 | 浙江大学 | High-sensitivity micro-resonant cavity photo-sensor |
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| CN103308480A (en) * | 2013-05-16 | 2013-09-18 | 成都谱视科技有限公司 | Grating FP (Fabry-Perot) cavity and micro-ring resonator cascade-form optical biochemical sensing chip |
| CN103487406A (en) * | 2013-09-24 | 2014-01-01 | 电子科技大学 | Vertical coupling Mach-Zehnder interference type microring resonant cavity optical biochemical sensing chip |
| EP2952942A1 (en) * | 2014-06-04 | 2015-12-09 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO | Photonic integrated circuit |
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