260 results about "Evanescent wave" patented technology

The invention discloses a light-induced thermoelastic spectrum trace gas detection device and method based on an echo wall mode microcavity. The device comprises a first signal generator, a lock-in amplifier, a laser device control unit, a first laser device, a laser beam collimation unit, a gas chamber, a focusing lens, a tuning fork, an echo wall mode microcavity, a coupling medium, a second laser device, a second signal generator, a photoelectric detector and a computer, the emergent laser is focused to the interdigital root of the tuning fork through the focusing lens; laser output by the second laser device is transmitted by the coupling medium and coupled into the echo wall mode microcavity in an evanescent wave form, the echo wall mode microcavity deforms, the resonant wavelength of the echo wall mode microcavity in the transmitted spectrum moves, and the concentration of the gas to be detected in the gas chamber is inverted according to the displacement of the resonant wavelength. The problems that a quartz tuning fork is large in thermal noise and weak current signals are easily interfered by an electromagnetic field are solved.

The invention provides a detection system of a micro optical fiber coupler based on a bidirectional optical frequency comb vernier effect, which can be applied to the technical field of photoelectric detection. The system comprises: an optical frequency comb light source configured to emit detection light; the beam splitter is arranged to split the detection light into first sub-detection light and second sub-detection light; the reference sensing unit is arranged to guide the first sub detection light to interact with a reference solution through an evanescent field of the first micro optical fiber coupler so as to output first transmission light; the detection sensing unit is arranged to guide the second sub detection light to interact with the solution to be detected through an evanescent field of the second micro optical fiber coupler so as to output second transmission light; the beam combiner is set to combine the first transmission light and the second transmission light to obtain a combined light spectrum; the spectrum analyzer is set to collect the combined light and generate a vernier spectrum; and the processor is set to determine the concentration of the liquid to be detected according to the vernier spectrum.

The present invention discloses a nanoparticle transport device, comprising a silica substrate, a droplet-shaped gold nanoarray, polarized light waves, and nanoparticles; the silica substrate serves as a substrate; the droplet-shaped gold nanoarray is disposed on the silica substrate and serves as a driving unit, interacting with the polarized light field to form an excited local electric field to capture and directionally transport nanoparticles; the polarized light wave is used to provide a light source, interacting with the droplet-shaped gold nanoarray to generate an evanescent field; the nanoparticles serve as the objects to be captured and transported; the droplet-shaped gold nanoarray includes a periodically arranged droplet-shaped plasma gold nanostructure, which is composed of a droplet-shaped tail and a circular body, and the transport direction of the nanoparticles forms a certain angle with the droplet-shaped tail. The present invention can achieve more stable capture with lower light power, and also enables the device to achieve highly operational transport of target particles.

The invention discloses a surface plasmon resonance imaging system for expanding a dynamic range through a multi-mode optical path, and relates to the technical field of microscopic imaging, a laser outputs a monochromatic and linearly polarized continuous wave beam, a first dynamic beam deflection device performs dynamic angle deflection adjustment on the continuous wave beam, a prism is used for providing a total reflection interface, and a second dynamic beam deflection device is used for performing dynamic angle deflection adjustment on the continuous wave beam. Exciting an evanescent wave; a surface plasma resonance effect is generated through interaction of the SPR detection chip and evanescent waves, and sample characteristics are detected; the flow cell provides a sample flow channel, so that a sample is in full contact with the surface of the SPR detection chip; the second dynamic light beam deflection device cooperatively adjusts the propagation direction of reflected light on the surface of the SPR detection chip, and the imaging detection device captures a high-spatial-resolution SPR image formed by the reflected light and transmits the image to the upper computer in real time for processing and analysis. According to the invention, the change of the resonance angle can be tracked in real time, and high-sensitivity and high-resolution monitoring of the dynamic process of biomolecule interaction is realized.

The invention provides an optical fiber sensor design based on an optical fiber Mach-Zehnder interferometer (MZI), and particularly relates to an in-fiber ladder-shaped special structure, which is particularly suitable for online monitoring of a reaction process in a microfluidic system and can measure refractive indexes of three points in the reaction process at the same time. The optical fiber sensor is formed by welding a common single-mode optical fiber, a coreless optical fiber and a stepped single-mode optical fiber. The broadband light source emits an optical signal through the single-mode optical fiber, a high-order mode excited in the coreless optical fiber enters a cladding of the single-mode optical fiber to be transmitted, due to the effect of an evanescent field and the influence of the environment refractive index and the temperature, the signal excites multiple modes in the optical fiber through the cascaded coreless optical fiber, and the high-order mode is transmitted in the cladding of the single-mode optical fiber. And an optical path difference is introduced through a step structure positioned between the two coreless optical fibers. When a solution to be detected is immersed into the stepped groove, the structure can generate refractive index change, and the propagation path of light can be adjusted by finely adjusting different sizes of the stepped groove to generate different phase differences, so that the light is coupled back into a fiber core of the single-mode fiber at the other end in the coreless fiber cascaded at the other end; and due to the special step-shaped structure, the refractive index values at three positions of the central step can be measured at the same time. According to the design, the structure of a traditional Mach-Zehnder interferometer is optimized, the number of elements is reduced, the stability and reliability of the system are improved, and the Mach-Zehnder interferometer is suitable for the fields of precision measurement, environment sensing, optical fiber communication and the like.

The invention discloses an underwater structure low-frequency radiation sound power forecasting method based on blind source separation, and the method comprises the following steps: (1), setting a housing sound source in a shallow sea environment, and obtaining discrete sound pressure; (2) obtaining an estimation signal of the source signal through a blind source separation algorithm; (3) windowing the estimated signal space data of the source signal in the z direction to obtain the sound pressure propagating outwards after windowing; (4) the sound pressure propagating outwards is converted into a wave number domain through discrete space Fourier transform, and a holographic surface sound pressure cylindrical wave spectrum is obtained; (5) filtering evanescent waves in a wavenumber domain by using a wavenumber domain filter to obtain propagation waves on a holographic surface; (6) transmitting the filtered sound pressure to a far field in a spherical shape through a near-field acoustical holography technology by means of stable-phase estimation; (7) deducing the sound intensity by using the far-field sound pressure so as to obtain the radiation sound power; according to the invention, the measurement workload is reduced; measurement is carried out on a holographic surface close to a sound source, the influence of boundary reflection is small, and a calculation result is accurate.

An antenna module includes an antenna unit and a first isolation unit. The antenna unit includes a first antenna and a second antenna arranged at an interval. The first isolation unit is arranged between the first antenna and the second antenna and configured to convert a transmission form of an electromagnetic wave coupled into the first isolation unit from the first antenna and / or the second antenna into an evanescent wave, to isolate a target signal between the first antenna and the second antenna.

The invention belongs to the technical field of integrated photonic devices, and particularly relates to an electric tuning silicon nitride waveguide multimode interference coupler based on a two-dimensional material covering layer. In order to solve the problem that an existing silicon nitride photonic device lacks effective electro-optical regulation and control capacity, a two-dimensional material covering layer (such as molybdenum disulfide and tungsten disulfide) is integrated on the surface of a silicon nitride waveguide, and an up-and-down structure of a metal electrode-two-dimensional material-silicon dioxide cladding-silicon nitride waveguide is constructed. When external bias voltage is applied, the effective refractive index of the waveguide mode is changed through evanescent field coupling by means of the electrical refraction effect of the two-dimensional material, and active regulation and control of the optical path of the silicon nitride waveguide without the thermo-optic effect are achieved. Compared with a lithium niobate-silicon nitride heterogeneous integration scheme, the two-dimensional material with the atomic layer thickness is compatible with the CMOS technology, a complex heterogeneous bonding technology is not needed, and the advantage of monolithic integration is achieved. The device is particularly suitable for a reconfigurable optical signal processing device in a silicon-based photon integrated circuit.

The present application relates to a kind of method and kit for detecting methylation cysteine total amount, belong to the field of biotechnology and analytical test.Utilize nucleic acid aptamer with high response to free Hcy, with moderate corresponding state Hcy to construct evanescent wave optical fiber sensor.Complementary strand and tHcy of fluorescently labeled are combined with the nucleic acid aptamer fixed on optical fiber with competition.Fluorescence signal drop value is positively correlated with tHcy concentration in serum.According to the percentage of fluorescence reduction, the tHcy concentration in serum is calculated.The present application detects tHcy only needs 1 microliter serum, after diluting 1000 times, detection is carried out, and the detection result is consistent with commercial enzyme cycle method.Compared with enzyme cycle method, the present application has the advantages of low price, optical fiber can be reused more than 30 times, detection speed is fast, fastest 5 minutes, does not need enzyme, equipment miniaturization, simple operation, etc., has excellent clinical application value.

This application provides a self-injection-locked narrow-linewidth laser with a quasi-continuous locking region, comprising: a semiconductor laser source for generating an initial linewidth laser and outputting it via end-face coupling; a photonic integrated microcavity chip including a bus waveguide and a microring resonator coupled to it via an evanescent wave, for receiving the initial linewidth laser and providing feedback light to the semiconductor laser through Rayleigh backscattering of the microring resonator to excite a self-injection-locking effect; the microring resonator is a compact folded waveguide microcavity with an ultra-low free spectral range, the free spectral range of which is less than a preset threshold, so that when the driving current of the semiconductor laser is changed for wavelength tuning, the self-injection-locking regions of adjacent resonant modes in the cavity physically overlap or are closely spliced ​​in the current tuning parameter space, so that the semiconductor laser can continuously transition between adjacent modes without experiencing permanent unlocking during continuous current tuning, forming a quasi-continuous locking region.

The invention relates to the field of optical fibers, in particular to a D-type optical fiber based on Fe3GaTe2 nanosheets and a preparation method and application of the D-type optical fiber. The invention discloses a D-type optical fiber based on a Fe3GaTe2 nanosheet. The D-type optical fiber comprises a D-type optical fiber and a Fe3GaTe2 layer deposited on a D-type plane of the D-type optical fiber. By utilizing the evanescent field characteristic of the D-type optical fiber, the Fe3GaTe2 nanosheet is deposited on the D-type plane of the D-type optical fiber, and magnetic anisotropy change (such as magnetization direction switching) is generated under the action of an external magnetic field, so that the effective refractive index of the optical fiber is changed; the change is converted into an optical path difference in the Michelson interferometer. Finally, the magnetic field intensity can be inverted by measuring the FSR change of the interference spectrum. The room-temperature MA adjustability of the Fe3GaTe2 nanosheets provides a larger refractive index change range (superior to that of magnetic fluid), and the nanosheets are not easy to degrade, so that the D-type optical fiber has higher sensitivity and temperature performance.

The present application relates to a kind of based on micro-nano fiber and scattering medium substrate coding element and speckle spectrometer.The coding element includes sealed cavity, micro-nano fiber and scattering medium substrate;Including drawstring transition zone and waist zone in the body of micro-nano fiber, drawstring transition zone forms leaky mode, waist zone generates evanescent field, the body of micro-nano fiber penetrates sealed cavity, so that drawstring transition zone and waist zone are located in sealed cavity;Scattering medium substrate is fixed in sealed cavity, and the waist zone of micro-nano fiber is overlapped on scattering medium substrate, scattering medium substrate is used to receive evanescent field and is coupled leaky mode to obtain scattering pattern information;Wherein, in the direction parallel to waist zone, scattering medium substrate includes more than two scattering zones, and the light transmittance of each scattering zone is different, and the difference between maximum light transmittance and minimum light transmittance is 20%~80%.Speckle spectrometer using the coding element of the present application has the advantages of small size, low cost while high spectral resolution.

The invention discloses a photoelectric hybrid long-period fiber grating sensor. The photoelectric hybrid long-period fiber grating sensor comprises a micro-nano optical fiber, polydimethylsiloxane and a laser-induced graphene electrode array, two ends of the micro-nano optical fiber are respectively used as an optical signal input port and an optical signal output port; the micro-nanofiber is packaged by polydimethylsiloxane and patterned by laser-induced graphene to form a periodically arranged laser-induced graphene electrode array, and the laser-induced graphene electrode array generates a periodic refractive index modulation effect on the middle area of the lower-layer micro-nanofiber and meets the phase matching condition of the long-period grating. And the micro-nano fiber long-period fiber grating is formed. The large evanescent field characteristic of the micro-nano fiber and the high refractive index sensitivity characteristic of the long-period grating can be fully utilized, the conductive electrode of the modulation grating is used for sensing application, and the functions of electrical detection and optical detection are achieved.

The application provides a visual micro-nano optical waveguide refractive index sensing system, and a hardware part comprises a nano fiber taper coupled fluorescent doped polymer microwire; the nano fiber taper coupled fluorescent doped polymer microwire is coupled by a nano fiber taper and a fluorescent doped polymer microwaveguide; the nano fiber taper is obtained by adopting a flame tapering method from a standard single-mode optical fiber; the fluorescent doped polymer microwaveguide is directly prepared by wire drawing from a mixed solution doped with a fluorescent dye; the nano fiber taper and the fluorescent doped polymer microwaveguide placed in a channel of an optical substrate jointly form an evanescent wave coupling structure; a signal analysis part enhances, edge extracts, smoothes and peak extracts a fluorescent image of the microwire through an image analysis algorithm, obtains an oscillation period of a fluorescent light path in the microwire under a current environment, establishes a response relationship between the light path period and the environmental refractive index, realizes direct real-time obtaining of environmental change conditions from optical images of a sensing unit shot by a camera, and thus obtains the change of the refractive index.

The application discloses a kind of optical fiber humidity sensor and its preparation scheme, optical fiber humidity sensor includes micro-nano optical fiber and porous film;Wherein: the micro-nano optical fiber, at least one bending part is formed;The porous film is coated on the surface of the bending part;The porous film surface has a plurality of holes, which is configured to be able to swell by water absorption, so that the duty cycle of hole becomes smaller.The present application utilizes the evanescent field of U-shaped micro-nano optical fiber to couple with the porous film to realize humidity sensing.Under different relative humidity environment, the size of the hole of the porous film on the surface of the U-shaped micro-nano optical fiber is different, so that the size of the energy scattered by it is different, and the change of the optical power at the output end of the optical fiber is different, thereby realizing humidity sensing.The present application has the advantages of high sensitivity, fast response speed, high repeatability and stability.

The invention discloses a surface plasma-based reverse Cherenkov medium laser accelerator, which is characterized in that a silicon medium prism, a first silver metal film, a first silicon medium film, a high-vacuum particle channel, a second silicon medium film, a second silver metal film and a silicon medium substrate are sequentially arranged from top to bottom to form a seven-layer metal-medium alternating structure; single-side incident laser excites surface plasma to realize particle acceleration. Incident electromagnetic waves are subjected to total internal reflection at the bevel edge of the prism, evanescent waves are generated, the longitudinal wave vector component of the evanescent waves meets the excitation condition of SPPs at the medium-metal layer interface, then the SPPs are excited on the metal-medium interface, and a remarkably enhanced near field is generated. The enhanced electric field forms longitudinal accelerating fields which are symmetrically distributed in the high-vacuum particle channel, and energy gain is continuously provided for electrons; meanwhile, the transverse electric field component is minimized in the central area of the channel due to mutual offset of upper and lower components, so that particle deflection is effectively inhibited.

This application discloses a fiber optic fluorescence level sensor based on evanescent waves, relating to the field of fiber optic sensing. The sensor includes: a light source module that outputs excitation light, which is sent to a fiber optic sensing unit to generate a fluorescence signal; a transmission fiber responsible for bidirectional signal transmission; a fiber optic sensing unit comprising a fiber optic strip D-groove structure, an encapsulation structure, a sensitive material, and a floating piston. The piston divides the encapsulation structure into two sections: the lower section contains the liquid to be measured, and the upper section integrates the sensitive material and the fiber optic strip D-groove structure. The piston floats synchronously with the liquid surface, changing the effective contact area between the sensitive material and the fiber optic strip D-groove structure, causing a regular change in the fluorescence intensity excited by the evanescent wave; a fiber optic spectrometer to acquire wavelength-intensity spectral information; and a computer module to perform data visualization, achieving real-time liquid level monitoring based on changes in fluorescence intensity. This sensor can improve upon the problems of existing fiber optic level sensors, such as complex fabrication, high cost, limited range, high equipment requirements, and poor adaptability to harsh environments.

A laser lithotripsy system may include a light energy source and a catheter. The catheter may comprise an optical fiber comprising a core and a cladding that encases the core. The optical fiber may be configured to be optically coupled to receive laser light from the light energy source. The optical fiber may include at least one evanescent portion and at least one non-evanescent portion. When light propagates through the core, an evanescent field may be transmitted out of the optical fiber in the evanescent portion and may not transmitted out of the optical fiber in the non-evanescent portion.

Optical states in TIR-based image displays may be modulated by movement of electrophoretically mobile particles into and out of the evanescent wave region at the interface of a high refractive index convex protrusions and a low refractive index medium. The movement of particles into the evanescent wave region may frustrate TIR and form dark states at pixels. Movement of particles out of the evanescent wave region may allow for TIR of incident light to form bright states at pixels. The movement of the particles may be controlled by employing the drive methods of pulse width modulation, voltage modulation or a combination thereof.

The embodiment of the invention relates to an optical assembly of an integrated waveguide and an optical chip. According to some embodiments of the present application, a waveguide-integrated optical assembly includes: a first waveguide having a first end; the second waveguide is provided with a second end and is parallel to the first waveguide, and the second end of the second waveguide is coupled with the first end of the first waveguide; the optical device is located in the second waveguide, and the surface of at least one of the first end of the first waveguide and the second end of the second waveguide is gradually shrunk in the tail end direction so that light can enter the second waveguide from the first waveguide in an evanescent wave coupling mode. Another embodiment of the invention provides an optical chip. The optical chip comprises one or more optical assemblies. The optical assembly of the integrated waveguide and the optical chip provided by the embodiment of the invention can effectively solve the problems encountered in the traditional technology.

The invention belongs to the technical field of power equipment monitoring, and particularly relates to an infrared optical fiber sensor for detecting the content of trace water in an oil sample and a detection device. According to the infrared optical fiber sensor, the structural design with the micro-fluidic chip is adopted, the hollow-core anti-resonance optical fiber subjected to tapering treatment is combined with the micro-fluidic chip, and the sensing performance is improved through cooperation of the hollow-core anti-resonance optical fiber and the micro-fluidic chip. The hollow-core anti-resonance optical fiber is subjected to tapering treatment, so that the transmission loss of infrared light is effectively reduced, the penetration depth of evanescent waves is enhanced, the detection sensitivity of the sensor on water in an oil sample is remarkably improved, and the detection limit can reach an extremely low level. And the micro-fluidic chip is used for accurately guiding the oil sample to flow through the optical fiber taper region to ensure that the sample to be detected is in full contact with the evanescent wave region, meanwhile, the sample consumption is reduced, and the detection efficiency is improved. Based on the principle that water molecules absorb infrared light, the detection of trace water in an oil sample has high selectivity, and interference of environmental factors such as temperature is avoided.

Implantable devices and / or sensors can be wirelessly powered by controlling and propagating electromagnetic waves in a patient's tissue. Such implantable devices / sensors can be implanted at target locations in a patient, to stimulate areas such as the heart, brain, spinal cord, or muscle tissue, and / or to sense biological, physiological, chemical attributes of the blood, tissue, and other patient parameters. The propagating electromagnetic waves can be generated with sub-wavelength structures configured to manipulate evanescent fields outside of tissue to generate the propagating waves inside the tissue. Methods of use are also described.

The application provides a photoelectric detector and a manufacturing method thereof, the photoelectric detector comprising: a waveguide arranged on a substrate and composed of a first material; and a light absorption layer arranged on a surface of the waveguide; the light absorption layer comprises a first material part and a second material part, the first material part is provided with a recess part, the second material part is arranged in the recess part, the first material part is composed of the first material, the second material part is composed of a second material, and the refractive index of the first material is smaller than that of the second material for the light of the predetermined wavelength. According to the application, the light absorption layer of the photoelectric detector is arranged in a structure formed by alternately arranging two materials with different refractive indexes, thereby increasing the absorption rate of the evanescent wave in the absorption layer, and high responsivity and high bandwidth are achieved.

The invention provides an optical waveguide and heterojunction two-dimensional material integrated nonvolatile storage structure and an application method, and relates to the technical field of photoelectron integration. A heterojunction two-dimensional material layer is arranged in an evanescent field area of an optical waveguide layer, so that when an electric field pulse is applied to the heterojunction two-dimensional material layer through a positive electrode layer and a negative electrode layer, the heterojunction two-dimensional material layer is not subjected to evanescent field pulse; the heterojunction two-dimensional material layer can generate various non-volatile heterojunction polarization states, so that the optical constant and the optical state of the non-volatile storage structure are changed, the optical state can be stored by utilizing the non-volatility, and the optical memory function is realized. Even under the condition of power failure, the stored optical state cannot be lost, and ultra-low static power consumption can be realized. The overturning of the polarization state of the heterojunction is realized by the overturning of the heterojunction domain, so that the power consumption of the nonvolatile storage structure is far lower than the heat power consumption required by a phase change memory or a thermo-optic device.

The invention provides an on-chip optical sensor for medical detection and a manufacturing method thereof, and relates to the technical field of on-chip optical sensors. According to the scheme, the device mainly comprises a substrate, a double-peak waveguide interference structure, a near-infrared photoelectric detector and a micro-fluidic channel, the double-peak waveguide interference structure is arranged on the upper surface of the substrate, comprises a waveguide layer and is used for amplifying refractive index change and outputting an interference signal; the micro-fluidic channel and the near-infrared photoelectric detector are respectively arranged in a sensing area and an output area on the upper surface of the waveguide layer; recognition molecules are arranged in the micro-fluidic channel and are used for being specifically combined with target molecules of a medical sample and generating refractive index change; and the near-infrared photoelectric detector is used for reading the interference signal and converting the interference signal into an electric signal. According to the scheme, the machinable absorption layer is directly integrated in the evanescent field area of the double-peak waveguide, on-chip direct reading of waveguide interference signals is achieved, coupling loss is reduced, and the signal-to-noise ratio is remarkably increased.

The utility model discloses a combined type fluorine ion sensing device which comprises a laser beam emitting light source, a collimating lens is arranged on the side face of the laser beam emitting light source, and the emitting path of the laser beam emitting light source is arranged right opposite to the input end of the collimating lens, so that laser beams emitted by the laser beam emitting light source can enter the collimating lens smoothly and accurately. The end part of the collimating lens is connected with an evanescent wave optical fiber spherical sensor through a transmission optical fiber, and a shell of the transmission optical fiber is connected with composite detection test paper through a wire. According to the device, the functions of high fluorine ion selectivity, short detection time, high accuracy and low cost are realized.

The invention discloses a high-responsivity photoelectric detector using an air cavity, which is characterized in that a dilution waveguide, the air cavity and a photoelectric detector are integrated on a semi-insulating substrate, and the air cavity is obtained in a dilution waveguide layer in an etching and wafer bonding mode; and finally, the transition waveguide and the photoelectric detector table are etched according to a conventional technological process. When the photoelectric detector works, the vast majority of signal light incident from the side surface is gradually coupled to the active region under the guidance of the dilution waveguide in front of the air cavity, and the leakage of the light from the active region to the dilution waveguide and the semi-insulating substrate below is effectively inhibited due to the large refractive index difference between the air cavity and the surrounding material; most of the light is limited in the active area and is converted into an electric signal after being absorbed by the absorption layer. According to the air cavity structure, the penetration depth of evanescent waves at the interface of the dilution waveguide and the air cavity can be reduced, the concentration degree of light in an active area is effectively improved, and the responsivity of the photoelectric detector is improved.

A radiation source unit (10) for carrying out an optical measurement has a radiation source (12), an optical conductor (13) for guiding radiation generated by the radiation source (12), and a substrate (16). The optical conductor (13) is designed to conduct a propagating mode. The radiation source unit (10) has a reference measuring device (14, 15) for carrying out a reference measurement, by means of which a change in a spectral characteristic of the radiation source (12) can be detected. The reference measuring device (14, 15) has a wavelength reference (14) which is arranged along at least one part of the optical conductor (13) in such a way that an evanescent field of the propagating mode enters the wavelength reference (14).

The invention relates to the technical field of gas concentration detection, in particular to a gas concentration sensor based on a resonant cavity, a preparation method of the gas concentration sensor and a detection system. The gas concentration sensor based on the resonant cavity comprises a microcavity which comprises an input end, a first Bragg grating and a second Bragg grating which are arranged in sequence; the input end is configured to receive a laser light source; the first Bragg grating and the second Bragg grating are symmetrically arranged, and the periodicity and the etching depth of the first Bragg grating and the second Bragg grating are the same; the resonant cavity is located between the first Bragg grating and the second Bragg grating; the gas chamber covers the second Bragg grating, and gas to be detected is contained in the gas chamber; the output end is coupled with the microcavity in an evanescent field mode, and the output end is configured to output an optical signal corresponding to the gas to be detected. The resonant cavity-based gas concentration sensor provided by the embodiment of the invention is simple in structure and simple in preparation process, and the detection precision of gas concentration can be improved.

The invention relates to the technical field of optical detection, and discloses a super-resolution optical detection system and method for material surface defects. According to the system and the method, a structured evanescent wave field is formed on the surface of a plasmon evanescent wave chip to serve as a near-field illumination probe, the relative position of the probe and a sample is changed through non-mechanical scanning modes such as angle or wavelength tuning, and a group of far-field polarization resolution diffraction patterns are acquired by a diffraction signal acquisition module. And the central control and data processing unit performs iterative computation by adopting a vector coherence diffraction imaging algorithm based on the diffraction data set, and reconstructs complex amplitude distribution of the probe and a high-resolution Jones matrix image of the sample at the same time. By analyzing the Jones matrix, quantitative detection of the morphology, the size and the anisotropic physical attributes of the surface defects can be completed. According to the invention, vibration caused by mechanical scanning is avoided, and high-stability and high-resolution nondestructive testing is realized.