PHOTONIC DEVICE FOR THE SIMULTANEOUS ACQUISITION OF SPECTROSCOPIC AND PHYSICO-CHEMICAL DATA OF AN ANALYTE, ASSOCIATED SYSTEM AND METHOD

Abstract

The invention relates to a photonic device (100) for the simultaneous acquisition of spectroscopic and physicochemical data of an analyte. The photonic device (100) comprises an optical source (110) that can be tunable or fixed wavelength, a spectroscopic sensor on a chip (120), and a variable spectral response optical element (130). The optical source (110) generates an excitation signal that can be tunable or fixed wavelength, the spectroscopic sensor on a chip (120) collects the spectroscopic signal scattered by the analyte, and the variable spectral response optical element (130) eliminates the residual signal while modifying its spectral response according to the physicochemical parameters of the analyte. When the optical source (110) is tunable, it adjusts the wavelength of the excitation signal.When the optical source (110) has a fixed wavelength, the variable spectral response optical element (130) is adjustable to maintain alignment. This configuration allows for the simultaneous acquisition of a spectroscopic signal of interest and information on the physicochemical properties of the analyte, thus providing precise and miniaturized multiparametric analysis. The invention solves the problem of correlating spectroscopic data with physicochemical parameters by integrating these functionalities onto a single chip, improving the sensitivity and miniaturization of analytical devices. Figure to be published with the abstract: Figure 1.

Description

Title of the invention: PHOTONIC DEVICE FOR THE SIMULTANEOUS ACQUISITION OF SPECTROSCOPIC AND PHYSICO-CHEMICAL DATA OF AN ANALYTE, ASSOCIATED SYSTEM AND METHOD technical field

[0001] The invention relates to the field of integrated spectroscopy and physico-chemical analysis of materials.

[0002] More particularly, it relates to a photonic device which allows the simultaneous acquisition of spectroscopic data and physico-chemical parameters of an analyte, as well as an associated system and method. Previous technique

[0003] Traditional spectroscopic techniques, such as Raman or fluorescence spectroscopy, are widely used for the analysis of the composition and structure of materials.

[0004] In parallel, various methods exist for measuring the physicochemical properties of samples, such as temperature, pressure or concentration.

[0005] However, these approaches generally require separate equipment and separate measurements, which can lead to temporal and spatial correlation problems between spectroscopic data and physicochemical parameters.

[0006] Moreover, existing devices often lack the sensitivity to detect small changes in analyte properties or require large sample volumes, limiting their application in certain fields such as cell biology or microfluidics.

[0007] Thus, there is a need for an integrated device capable of simultaneously acquiring spectroscopic data and information on the physicochemical parameters of an analyte, while offering increased sensitivity and advanced miniaturization. Summary of the invention

[0008] The invention aims to solve, at least partially, this need.

[0009] A first aspect of the invention relates to a photonic device for simultaneous acquisition, - of at least one spectroscopic signal of interest from an analyte, and - at least one initial piece of information which is designed to allow the determination of at least one physico-chemical parameter of the analyte.

[0010] In practice, the photonic device comprises, - an integrated architecture that includes optical components and integrated optical connections linking the optical components, the optical components including, — at least one optical source designed to generate, at at least one emission wavelength, at least one optical signal designed to excite the analyte, called the optical excitation signal, the optical source being either tunable in wavelength or of fixed wavelength, — at least one spectroscopic sensor on a chip, and — at least one integrated optical element with variable spectral response, in which, - when, — the optical source is tunable; it is further designed to adjust the wavelength of the optical excitation signal according to the detection of at least one change in all or part of the spectral response of the integrated optical element with variable spectral response, so as to maintain a constant alignment between the wavelength of the optical excitation signal and at least one predetermined spectral characteristic of the integrated optical element with variable spectral response; — the optical source has a fixed wavelength; the integrated optical element with variable spectral response is further designed to be adjustable so as to maintain a constant alignment with the fixed wavelength of the optical excitation signal. - The spectroscopic sensor on a chip is designed to collect the spectroscopic signal that is scattered by the analyte in response to irradiation of the analyte by the optical excitation signal, the collected spectroscopic signal comprising, — a residual optical signal having the same wavelength as the excitation optical signal, and — at least one spectroscopic signal of interest having wavelengths different from that of the optical excitation signal, and - The integrated optical element with variable spectral response is designed such that the variation of its spectral response depends in a specific and quantifiable way on at least one physicochemical parameter of an analyte, the integrated optical element with variable spectral response being further designed to, — receive the collected spectroscopic signal, — eliminate the residual optical signal from the collected spectroscopic signal, so as to generate a collected and modified spectroscopic signal comprising the spectroscopic signal of interest, and — modify all or part of its spectral response as a function of the physicochemical parameter of the analyte, so as to allow the acquisition of the first information which is related to the physico-chemical parameter of the analyte, the modification being induced by a variation in the permittivity of the material constituting the optical element integrated with a spectral response that varies in response to the physico-chemical parameter of the analyte.

[0011] In a first embodiment of the first aspect of the invention, - the spectroscopic sensor on chip includes at least one input and at least one output, and - the integrated optical element with variable spectral response is arranged at the input and / or output of the spectroscopic sensor.

[0012] In a second embodiment of the first aspect of the invention, the integrated optical element with variable spectral response, the spectroscopic sensor on chip, and the optical source share a common substrate.

[0013] In a third embodiment of the first aspect of the invention, the spectroscopic sensor on a chip is chosen from, - a Raman-on-a-chip sensor that is designed to implement waveguide-amplified Raman spectroscopy technology, and - a fluorescence-on-chip sensor that is designed to implement waveguide-amplified fluorescence spectroscopy technology.

[0014] In a fourth embodiment of the first aspect of the invention, the integrated optical element with variable spectral response is selected from: - a tunable Bragg grating, - a variable-coupling ring resonator, - a liquid crystal photonic structure whose refractive index varies with temperature or pressure, - a multilayer interference filter whose bandwidth is shifted, - a Mach-Zehnder interferometer, - a silicon-on-insulator (SOI) waveguide, - a silicon nitride waveguide, - an optical fiber integrated into a microfluidic channel, - an integrated diffraction grating, - a directional coupler, - an integrated micro-resonator, - a photonic crystal, or - any combination of these, and in which the variable spectral response of the integrated optical element manifests itself through at least one of the following phenomena: - a change in the position of the bandwidth, - a variation in the wavelength of reflection, - a change in the peak transmission or reflection, - a shift in the resonance wavelength, - a variation in transmission, or - an induced phase change, depending on environmental conditions or an analyte control parameter.

[0015] In a fifth embodiment of the first aspect of the invention, the physico-chemical parameter of the analyte is selected from: a temperature, a strain, a stress, a pressure, a torque, a vibration, an acoustic wave, a magnetic field, an electric field, a biological substance, a chemical, a biochemical reaction, a drug, a protein, or a combination thereof.

[0016] A second aspect of the invention relates to a multiparametric analysis system for an analyte for the determination of its composition and at least one of its physico-chemical properties.

[0017] In practice, the system comprises, - at least one photonic device according to any one of claims 1 to 6, and - at least one signal processing unit designed to — process the initial information relating to the physicochemical parameter of the analyte to detect changes in all or part of the spectral response of the spectrally variable integrated optical element, and then apply the principles of refractometry to all or part of the changes in order to determine the value of the physicochemical parameter of the analyte, and — to process the spectroscopic signal collected and modified by the integrated optical element with variable spectral response to obtain at least a second piece of information which is related to the composition of the analyte.

[0018] In a first embodiment of the second aspect of the invention, the signal processing engine is designed to compensate for the wavelength shift of the spectroscopic signal due to the change in the wavelength of the optical excitation signal.

[0019] In a second embodiment of the second aspect of the invention, the signal processing unit is designed to perform wavelength shift correction of the spectroscopic signal according to at least one of the following methods, - a real-time correction adapted to the physico-chemical dynamics of the analyte and the performance of the integrated optical element with variable spectral response, and - a digital post-processing.

[0020] In a third embodiment of the second aspect of the invention, the signal processing engine is designed to operate in a calibration-free mode providing relative values ​​of the physicochemical parameter of the analyte.

[0021] In a fourth embodiment of the second aspect of the invention, the system further comprises at least one calibration processor which is designed to establish a correspondence between a specific spectral position of the integrated variable spectral response optical element and a known value of the physicochemical parameter of the analyte, and in which the signal processing processor is further designed to convert relative values ​​of the physicochemical parameter of the analyte into absolute values ​​using the established calibration.

[0022] A third aspect of the invention relates to a method of simultaneous acquisition - of at least one spectroscopic signal of interest of an analyte, and - of at least one first piece of information which is designed to allow the determination of at least one physico-chemical parameter of the analyte.

[0023] In practice, the process comprises the following steps: - to provide at least one photonic device according to any one of claims 1 to 6, - generate, using the optical source, an optical excitation signal with at least one emission wavelength, the optical source being either tunable in wavelength or having a fixed wavelength, - initially align the wavelength of the optical excitation signal with at least one predetermined spectral characteristic of the integrated optical element with variable spectral response, - irradiate the analyte with the optical excitation signal, - to collect, using the spectroscopic sensor on a chip, a spectroscopic signal scattered by the analyte, - eliminate, using the integrated optical element with variable spectral response, a residual optical signal from the collected spectroscopic signal having the same wavelength as the excitation optical signal, so as to generate a collected and modified spectroscopic signal comprising the spectroscopic signal of interest having wavelengths different from that of the excitation optical signal, - to acquire a first spectroscopic signal of interest for the analyte from the collected and modified spectroscopic signal, - detect a misalignment between the wavelength of the optical excitation signal and the predetermined spectral characteristic of the integrated optical element with variable spectral response due to a change in the physicochemical parameter of the analyte, - when the optical source is tunable, adjust the wavelength of the optical excitation signal to realign it with the predetermined spectral characteristic of the integrated optical element with variable spectral response, - when the optical source has a fixed wavelength, adjust the integrated optical element with variable spectral response to realign it with the fixed wavelength of the excitation optical signal, and - acquire the first information which relates to the physico-chemical parameter of the analyte as a function of the change in all or part of the spectral response of the optical element integrated with variable spectral response.

[0024] In a first embodiment of the third aspect of the invention, the misalignment detection step includes measuring the transmission of the optical excitation signal through the integrated optical element with variable spectral response.

[0025] In a second embodiment of the third aspect of the invention, the method further comprises a calibration step for, - to establish a correspondence between at least one predetermined spectral characteristic of the integrated optical element with variable spectral response and at least one known value of the physicochemical parameter of the analyte, and - use the correspondence to convert the change in all or part of the spectral response of the integrated optical element with variable spectral response into a value of the physico-chemical parameter of the analyte during the acquisition of the first information.

[0026] In a third embodiment of the third aspect of the invention, the method further comprises, - a step of acquiring a second spectroscopic signal of interest for the analyte from the collected and modified spectroscopic signal, with the wavelength of the optical excitation signal realigned, and - a correction step of the second spectroscopic spectrum based on the first information which relates to the acquired physico-chemical parameter. Brief description of the drawings

[0027] Other features and advantages of the invention will be better understood from the following description and with reference to the accompanying drawings, given by way of illustration and not limitation.

[0028] [Fig-1] Fig. 1 represents a schematic view of the photonic device according to the invention.

[0029] [Fig.2] Fig.2 represents a schematic view of the system according to the invention.

[0030] [Fig.3] Fig.3 represents a flowchart of a process according to the invention.

[0031] The figures do not necessarily respect the scales, particularly in thickness, for illustrative purposes.

[0032] In addition, some drawings are presented in color and / or transparency, as their representation in black and white is impossible. In particular, color is necessary in these drawings to discern details that would be lost if they were presented in black and white. Description of the implementation methods

[0033] Preliminary remarks

[0034] In order not to obscure the description and distract the reader from understanding the teachings of the invention, our explanations will not go beyond what is considered necessary for understanding and appreciating the underlying concepts of the invention. Indeed, the embodiments illustrated in the description are, for the most part, composed of elements known to those skilled in the art of the invention.

[0035] Description structure

[0036] The present description is organized in such a way as to guide the reader through the various aspects of the invention.

[0037] It begins with a presentation of the objectives of the invention, followed by a detailed description of the general structure of a photonic device. The main components are then explained in detail. The description also addresses the operation and interactions between these components.

[0038] Several embodiments are presented, illustrating various configurations and applications of the photonic device. The text continues with an explanation of the multi-parameter analysis system and the simultaneous acquisition method.

[0039] Finally, the description concludes with remarks on possible variants and potential applications of the invention.

[0040] This progressive structure allows the reader to understand the invention as a whole, from fundamental concepts to the finest technical details.

[0041] Object of the invention

[0042] One of the main objectives of the invention is to provide a photonic device capable of simultaneously acquiring spectroscopic data and information on physico-chemical parameters of an analyte.

[0043] To this end, the inventors propose an innovative integrated architecture that combines a tunable optical source, a spectroscopic sensor on chip and a variable spectral response optical element.

[0044] This configuration makes it possible to obtain both a spectroscopic signal of interest and information on the physico-chemical properties of the analyte, using the variations in the spectral response of the integrated optical element.

[0045] The invention thus aims to improve the correlation between spectroscopic data and physico-chemical parameters, while offering increased sensitivity and advanced miniaturization of the analysis device.

[0046] General structure of the invention

[0047] As illustrated in [Fig.1], a first aspect of the invention relates to a photonic device 100 for the simultaneous acquisition of spectroscopic and physicochemical data of an analyte.

[0048] More specifically, the device is designed for the simultaneous acquisition of at least one spectroscopic signal of interest from an analyte and at least one first piece of information which is designed to enable the determination of at least one physicochemical parameter of the analyte.

[0049] The term “analyte” means the substance or chemical compound that the photonic device 100 analyzes.

[0050] By way of example, the term "analyte" may refer to an aqueous solution containing proteins, a gaseous mixture in a reaction chamber, or a sample of biological tissue placed on a surface of the photonic device 100.

[0051] In practice, the term "simultaneous acquisition" refers to the ability of the photonic device 100 to obtain spectroscopic and physicochemical data of an analyte at the same time in at least one measurement operation.

[0052] In this context, a "measurement" corresponds to a complete cycle of operation of the photonic device 100, including the emission of the optical excitation signal, its interaction with the analyte, the collection of the resulting spectroscopic signal, and its processing by the integrated components of the photonic device 100.

[0053] Furthermore, simultaneous acquisition allows for real-time multi-parametric analysis.

[0054] By way of example, the term "simultaneous acquisition" may include the simultaneous measurement of the Raman spectrum of a molecule and its concentration, the simultaneous obtaining of the fluorescence spectrum of a protein and the temperature of the solution, or the parallel recording of the absorption spectrum of a gas and its partial pressure.

[0055] In the first aspect of the invention, the photonic device 100 comprises an integrated architecture which includes optical components and integrated optical connections which link these components.

[0056] More specifically, the optical components include a tunable optical source 110, an on-chip spectroscopic sensor 120, and an integrated optical element with variable spectral response 130, these components work together to achieve the simultaneous acquisition of spectroscopic signals of interest and physico-chemical information.

[0057] In practice, the photonic device 100 is designed to acquire at least one spectroscopic signal of interest from an analyte, this signal corresponding to the spectroscopic data according to the invention.

[0058] The term "spectroscopic signal" means the set of optical information collected by the spectroscopic sensor on chip 110 after the interaction of an optical excitation signal (described below, in connection with the tunable optical source 110) with the analyte.

[0059] The spectroscopic signal collected by the spectroscopic sensor on chip 110 comprises various components, including at least one spectroscopic signal of interest and residual optical signal.

[0060] By way of example, the term "spectroscopic signal" may refer to a complete Raman spectrum which includes the characteristic peaks of the analyte and Rayleigh scattering, a fluorescence spectrum with its emission and excitation bands, or an absorption spectrum with its characteristic lines and continuous background.

[0061] Indeed, the term "spectroscopic signal of interest" refers to the specific part of the spectroscopic signal that contains relevant information on the composition or structure of the analyte. This signal is distinguished from the residual optical signal by its wavelengths, which differ from those of the excitation optical signal.

[0062] By way of example, the term "spectroscopic signal of interest" may include the characteristic Raman peaks of an organic molecule, the fluorescence emission bands of a fluorophore, or the specific absorption lines of a gas.

[0063] Furthermore, the term "residual optical signal" refers to the portion of the collected spectroscopic signal that has the same wavelength as the excitation optical signal. This residual signal is generally considered background noise to be eliminated in order to isolate the spectroscopic signal of interest.

[0064] By way of example, the term "residual optical signal" may refer to Rayleigh scattering in a Raman experiment, elastic reflection or scattering of the excitation beam in a fluorescence measurement, or supercontinuum generation in a nonlinear optical fiber, where a single-wavelength laser pulse is converted into a broadband spectrum by nonlinear effects.

[0065] Furthermore, in the first aspect of the invention, the photonic device 100 is designed to allow the determination of at least one physico-chemical parameter of the analyte from at least one first piece of information, this first piece of information corresponding to the physico-chemical data of an analyte according to the invention.

[0066] In practice, the term "analyte physicochemical parameter" refers to a measurable property of the analyte that can affect its composition, structure or behavior.

[0067] By way of example, the term "analyte physicochemical parameter" may include the concentration of a chemical species in a solution, the temperature of a gaseous sample, the pH of a buffer solution, or the partial pressure of a gas in a mixture.

[0068] The tunable optical source

[0069] In the first aspect of the invention, the tunable optical source 110 designates a component of the photonic device 100 which is capable of generating an optical excitation signal whose wavelength can be adjusted.

[0070] In practice, the tunable optical source 110 contributes to the excitation of the analyte and, as described below, adapts to changes in spectral response of the integrated optical element with variable spectral response 130.

[0071] By way of example, the term "tunable optical source" may refer to a tunable external cavity laser, a temperature-tunable distributed feedback (DFB) laser diode, or a current-injection-tunable semiconductor laser.

[0072] The spectroscopic sensor on chip

[0073] In the first aspect of the invention, the spectroscopic sensor on a chip 120 is a miniaturized component that can be integrated directly onto a substrate or distributed across several substrates. It is designed to collect and analyze a spectroscopic signal scattered by the analyte. In some embodiments, the spectroscopic sensor on a chip 120 can be integrated and a single unit, i.e., all its elements are located on the same chip. However, in other embodiments, all the elements of the spectroscopic sensor on a chip 120 are not necessarily integrated onto a single chip.

[0074] The term "scattered spectroscopic signal" refers to the light emitted or scattered by the analyte in response to its irradiation by the optical excitation signal. The scattered spectroscopic signal contains information about the composition and structure of the analyte.

[0075] By way of example, the term "scattered spectroscopic signal" may include inelastic Raman scattering carrying information on molecular vibrational modes, fluorescence emission revealing the electronic structure of a fluorophore, or transmitted light in an absorption experiment, indicating the presence and concentration of certain chemical species.

[0076] Furthermore, the spectroscopic sensor on chip 120 may correspond to a Raman sensor on chip, a fluorescence sensor on chip, a miniaturized Fourier transform spectrometer, or an array of photodiodes integrated with spectral filters, these elements can be integrated on one or more chips depending on the embodiment.

[0077] In practice, the spectroscopic sensor on chip 120 is capable of distinguishing different components of the spectroscopic signal described above, namely, a residual optical signal and at least one spectroscopic signal of interest. This distinction capability can be achieved by components integrated on a single chip or distributed across several interconnected chips, depending on the specific configuration of the sensor.

[0078] Integrated optical element with variable spectral response

[0079] In the first aspect of the invention, the integrated optical element with variable spectral response 130 refers to a component of the photonic device 100 whose optical properties change depending on the physicochemical parameters of the analyte. For example, the variable spectral response may manifest itself by a change in the position of the bandwidth, the reflection wavelength, or the transmission / reflection peak depending on environmental conditions or a control parameter of the analyte.

[0080] By way of example, the integrated optical element with variable spectral response 130 may refer to a Bragg grating, a ring resonator, or a liquid crystal photonic structure whose refractive index varies with temperature or pressure. It may also refer to a multilayer interference filter whose bandwidth shifts, or a Mach-Zehnder interferometer.

[0081] In practice, as we will explain below, the integrated optical element with variable spectral response 130 fulfills several functions: it receives the collected spectroscopic signal, eliminates the residual optical signal, and modifies its spectral response according to the analyte.

[0082] Integrated architecture and integrated optical connections

[0083] In the first aspect of the invention, the integrated architecture refers to the overall design of the photonic device 100, where the optical components can be integrated on a single substrate or distributed across several interconnected substrates. The optical connections can be integrated directly into the substrate or made by external means connecting different components. This flexibility makes it possible to adapt the configuration of the photonic device 100 to the specific requirements of the intended application.

[0084] In practice, optical connections ensure signal guidance between the various components of the photonic device 100, in particular the tunable optical source 110, the integrated variable spectral response optical element 130, and the spectroscopic sensor on-chip 120. These connections can be implemented in the form of waveguides integrated on the same chip, or by optical links between separate components, thus offering great versatility in the design and optimization of the device.

[0085] By way of example, the term "integrated optical connections" may include silicon-on-insulator (SOI) waveguides, silicon nitride waveguides, or optical fibers integrated into microfluidic channels, or optical fibers linking separate integrated photonic components.

[0086] Operation and interactions of the components of the photonic device

[0087] First, the tunable optical source 110 generates at least one optical excitation signal. As described above, the optical excitation signal is tunable in wavelength and is designed to excite the analyte.

[0088] The term “optical excitation signal” means the light radiation generated by the tunable optical source 110 and used to stimulate the analyte.

[0089] By way of example, the term "optical excitation signal" may refer to a monochromatic laser beam, which may be in the ultraviolet, visible or near infrared, for Raman spectroscopy, or for fluorescence spectroscopy, or infrared radiation for absorption spectroscopy.

[0090] Furthermore, the term "excite" refers to the process by which the optical excitation signal interacts with the analyte, causing temporary changes in its energy states, such as electronic, vibrational, or rotational transitions. This excitation leads to the production of a scattered spectroscopic signal.

[0091] By way of example, the term "excite" may include the induction of molecular vibrations for Raman spectroscopy, the promotion of electrons to excited states for fluorescence, or the stimulation of rotational or vibrational transitions for absorption spectroscopy.

[0092] Then, the tunable optical source 110 adjusts the wavelength of the optical excitation signal according to the detection of at least one change in all or part of the spectral response of the integrated optical element with variable spectral response 130. This adjustment is carried out by a feedback mechanism which measures the response of the optical element and actively controls the source.

[0093] The term "spectral response of the integrated optical element with variable spectral response" refers to the way in which the integrated optical element with variable spectral response 130 interacts with light as a function of wavelength. This response changes according to the physicochemical parameters of the analyte, thus allowing their determination.

[0094] By way of example, the term "spectral response of the integrated optical element with variable spectral response" can refer to the shift in the resonance wavelength of a Bragg grating as a function of temperature, the variation in the transmission of a pressure-dependent interference filter, or the phase change induced in an interferometer as a function of the concentration of an analyte.

[0095] With this arrangement of the integrated optical element with variable spectral response 130, a constant alignment is maintained between the wavelength of the optical excitation signal and at least one predetermined spectral characteristic of the integrated optical element with variable spectral response 130.

[0096] The term “constant alignment” refers to the correspondence maintained between the wavelength of the optical excitation signal and a predetermined spectral characteristic of the integrated optical element with variable spectral response 130.

[0097] By way of example, the term "constant alignment" may include maintaining the excitation wavelength on the flank of an optical resonance, synchronizing the laser wavelength with the transmission maximum of a variable filter, or continuously adjusting the excitation frequency to follow the movement of an absorption peak.

[0098] In this way, the tunable optical source 110 adjusts the wavelength of the optical excitation signal to compensate for changes detected in the spectral response of the integrated variable spectral response optical element 130. This adjustment process involves continuous measurement of the spectral response and active control of the tunable optical source 110 to maintain the desired spectral alignment. Maintaining this alignment primarily ensures the efficiency of the optical filtering and optimizes the detection of the spectroscopic signal of interest. This optimization indirectly contributes to improving the quality of the spectroscopic measurements.

[0099] By way of example, this maintenance may refer to the real-time adjustment of the wavelength of a distributed feedback (DFB) laser to follow the displacement of an optical resonance of an integrated micro-resonator, the modulation of the voltage applied to an external cavity laser to compensate for temperature variations of an optical filter, or the dynamic adaptation of the frequency of a parametric optical oscillator to stay in phase with a specific molecular transition.

[0100] The term "predetermined spectral characteristic" refers to a specific and previously identified attribute of the spectral response of the integrated optical element with variable spectral response 130. This characteristic serves as a reference point for aligning the optical excitation signal and for calibrating the device. It is chosen for its sensitivity to changes in the physicochemical parameters of the analyte and for its stability under the device's operating conditions.

[0101] By way of example, the term "predetermined spectral characteristic" may refer to the resonance wavelength of an integrated Bragg grating, which varies with the analyte temperature, the transmission peak of a ring resonator, which shifts with the analyte concentration, or the spectral position of a minimum interference in a Mach-Zehnder interferometer, which changes depending on the analyte pressure.

[0102] The predetermined spectral characteristic is used as a reference to maintain constant alignment between the wavelength of the optical excitation signal and the integrated optical element with variable spectral response 130. In addition, it serves as a basis for calibrating the device, allowing a correspondence to be established between the observed spectral changes and the values ​​of the physicochemical parameters of the analyte.

[0103] The use of a predetermined spectral characteristic allows for precise and reproducible measurement of the analyte's properties. It ensures that changes in the spectral response of the optical element are interpreted consistently, thus providing reliable information on the physicochemical parameters of the analyte under study. This approach improves the sensitivity and accuracy of the photonic device 100 in the simultaneous acquisition of spectroscopic and physicochemical data.

[0104] Then, the spectroscopic sensor on chip 120 collects the spectroscopic signal scattered by the analyte in response to irradiation by the optical excitation signal.

[0105] As described previously, the collected spectroscopic signal comprises two components: a residual optical signal having the same wavelength as the excitation optical signal, and at least one spectroscopic signal of interest having wavelengths different from that of the excitation optical signal.

[0106] Next, the integrated optical element with variable spectral response 130 plays several roles and can be strategically positioned in the device. It can be arranged at the input of the on-chip integrated spectroscopic sensor 120, at its output, or both as input and output, thus offering flexibility in the processing of the spectroscopic signal.

[0107] First, the integrated optical element with variable spectral response 130 receives the collected spectroscopic signal.

[0108] Next, the integrated optical element with variable spectral response 130 eliminates the residual optical signal from the collected spectroscopic signal, thereby generating a collected and modified spectroscopic signal comprising the spectroscopic signal of interest.

[0109] The term "elimination" refers to the action of selectively removing or filtering the residual optical signal that has the same wavelength as the excitation optical signal, while preserving the spectroscopic signal of interest that contains the relevant spectral information of the analyte. This elimination is achieved through the specific spectral properties of the integrated optical element with variable spectral response 130.

[0110] By way of example, the term "eliminate" may refer to the attenuation of the excitation signal by a Bragg grating tuned to specifically reflect this wavelength, suppression of the residual signal by a ring resonator whose resonance is tuned so as not to transmit the excitation wavelength, or filtering of the excitation signal by a Mach-Zehnder interferometer configured to create destructive interference at that specific wavelength.

[0111] Finally, the integrated optical element with variable spectral response 130 modifies all or part of its spectral response depending on the physico-chemical parameter of the analyte.

[0112] In practice, as explained previously, the variation of the spectral response of the spectrally variable optical element 130 depends specifically and quantifiably on at least one physicochemical parameter of the analyte. This allows for the acquisition of initial information regarding the physicochemical parameter of the analyte.

[0113] Indeed, the variation in the spectral response of the integrated optical element with variable spectral response 130 is directly and measurably linked to changes in the physicochemical parameter of the analyte. This relationship allows for a precise and reproducible determination of the physicochemical parameter of the analyte in question.

[0114] By way of example, this relationship may include a linear relationship between the wavelength shift of an optical resonator and the concentration of an analyte, an exponential variation of the transmission of a waveguide as a function of temperature, or a logarithmic dependence of the optical phase of an interferometer on the pressure of a gas.

[0115] Furthermore, we specify that this modification is induced by a variation in the permittivity of the material constituting the optical element integrated with variable spectral response 130 in response to the physico-chemical parameter of the analyte.

[0116] Permittivity is understood to be a physical property that describes the response of a material to an applied electric field. In the context of the spectrally variable integrated optical element 130, the permittivity of the material constituting the spectrally variable integrated optical element 130 changes in response to the physicochemical parameter of the analyte, thus resulting in a modification of its spectral response.

[0117] By way of example, the term "permittivity" may refer to the variation of the refractive index of a polymer as a function of humidity, to the change in the dielectric constant of a metal oxide in the presence of certain gases, or to the alteration of the optical properties of a piezoelectric material under the effect of a mechanical stress induced by the analyte.

[0118] First embodiment: configuration of the spectroscopic sensor and the variable response optical element in the photonic device

[0119] In a first embodiment of the photonic device 100, the spectroscopic sensor on chip 120 includes at least one input and at least one output.

[0120] The term "input" means the access point through which the optical signal enters the spectroscopic sensor on chip 120.

[0121] By way of example, the term "input" can refer to several elements. First, it can be an optical interface coupled to an optical fiber for injecting the excitation signal into the sensor. Second, the input can take the form of a nanometric aperture etched into the substrate to allow direct interaction between the analyte and the evanescent field of a waveguide. Third, it can consist of an integrated diffraction grating that couples the incident light in the plane of the photonic device. Finally, the input can be implemented by a directional coupler that transfers the optical signal from an access waveguide to the spectroscopic sensor.

[0122] Furthermore, the term "output" refers to the point through which the processed or modified optical signal leaves the spectroscopic sensor on chip 120. The output allows the transmission of the spectroscopic signal of interest to other components of the photonic device 100 or to an external detection system.

[0123] By way of example, the term “output” can encompass several configurations. First, it can be an output waveguide that carries the processed spectroscopic signal to an integrated photodetector. Second, the output can be an optical interface that allows coupling the output signal into an optical fiber for remote analysis. Furthermore, it can take the form of a diffraction grating that couples the spectral signal out of the plane of the photonic device 100 for free-space detection. Finally, the output can be implemented by an optical coupler that distributes the output signal to several parallel analysis channels on the same chip.

[0124] As regards the integrated optical element with variable spectral response 130, it is strategically positioned.

[0125] Indeed, the integrated optical element with variable spectral response 130 can be arranged at the input of the spectroscopic sensor on chip 120. Alternatively, the integrated optical element with variable spectral response 130 can be placed at the output of the spectroscopic sensor on chip 120. Furthermore, it is possible for the integrated optical element with variable spectral response 130 to be arranged both at the input and output of the spectroscopic sensor on chip 120.

[0126] The strategic arrangement of the integrated optical element with variable spectral response 130 relative to the inputs and outputs of the spectroscopic sensor 120 optimizes the processing of the spectroscopic signal and offers several advantages.

[0127] First, when the variable spectral response integrated optical element 130 is placed at the input, it can serve as a tunable filter to select the spectral band of interest before analysis. Then, positioned at the output, the variable spectral response integrated optical element 130 can perform post-processing of the signal, such as the elimination of residual optical signal. Finally, the arrangement at both input and output allows for finer control of the signal, with pre-filtering and post-processing that are tailored to the specific needs of the analysis.

[0128] Second embodiment: integration of the main components on a common substrate in the photonic device 100

[0129] In a second embodiment of the photonic device 100, the integrated optical element with variable spectral response 130, the spectroscopic sensor on chip 120, and the tunable optical source 110 are integrated on the same substrate.

[0130] More specifically, the integrated variable spectral response optical element 130, the spectroscopic sensor on chip 120, and the tunable optical source 110 share a common substrate.

[0131] The term "substrate" refers to the common material base on which the various components of the photonic device 100 are integrated. This substrate serves as a physical support and integration platform for the integrated optical element with variable spectral response 130, the spectroscopic sensor on chip 120, and the tunable optical source 110. The substrate contributes to the miniaturization, integration, and overall performance of the photonic device 100.

[0132] By way of example, the term "substrate" can refer to several types of materials. First, it can be a silicon-on-insulator (SOI) wafer, providing an excellent platform for integrating optical waveguides and photonic components. Second, the substrate can be composed of silicon nitride (Si3N4) on silicon dioxide (SiO2), enabling the fabrication of low-loss photonic structures in the visible and near-infrared. Third, a doped glass substrate, such as borosilicate glass, can be used for integrating passive and active optical components. Finally, a flexible polymer substrate, such as polyimide, can be used for applications requiring a certain degree of mechanical flexibility in the photonic device.

[0133] This configuration allows for compact integration of the various elements of the photonic device 100. In addition, sharing a common substrate can facilitate interconnections between components and potentially improve the overall performance of the photonic device 100.

[0134] Third embodiment: Raman sensor on chip using waveguide-amplified Raman spectroscopy

[0135] In a third embodiment of the photonic device 100, the spectroscopic sensor on chip 120 is specifically a Raman sensor on chip.

[0136] In practice, the technology used by the on-chip Raman sensor is waveguide-amplified Raman spectroscopy. This approach improves the sensitivity and efficiency of spectroscopic detection.

[0137] Thanks to the use of waveguide-amplified Raman spectroscopy, the on-chip Raman sensor can potentially detect and analyze weaker spectroscopic signals or smaller sample quantities.

[0138] Fourth embodiment: Fluorescence sensor on chip using waveguide-amplified fluorescence spectroscopy

[0139] In a fourth embodiment of the photonic device 100, the spectroscopic sensor on chip 120 is specifically a fluorescence sensor on chip.

[0140] In practice, the technology used by the fluorescence-on-chip sensor is waveguide-amplified fluorescence spectroscopy. This approach improves the sensitivity and efficiency of spectroscopic detection.

[0141] Through the use of waveguide-amplified fluorescence spectroscopy, the on-chip fluorescence sensor can potentially detect and analyze weaker fluorescence signals or smaller quantity samples.

[0142] Fifth embodiment: Varieties and characteristics of optical elements integrated with variable spectral response in the photonic device

[0143] In a fifth embodiment, the integrated optical element with variable spectral response 130 can be selected from several types of optical components.

[0144] More specifically, the integrated optical element with variable spectral response 130 can be a tunable Bragg grating, a variable coupling ring resonator, a liquid crystal photonic structure whose refractive index varies with temperature or pressure, a multilayer interference filter whose bandwidth shifts, or a Mach-Zehnder interferometer.

[0145] In addition, the integrated variable spectral response optical element 130 can also be a silicon-on-insulator (SOI) waveguide, a silicon nitride waveguide, an optical fiber integrated into a microfluidic channel, an integrated diffraction grating, a directional coupler, an integrated micro-resonator, or a photonic crystal.

[0146] It is important to note that any combination of these elements can also be used.

[0147] In practice, the variable spectral response of the integrated optical element 130 manifests itself through different phenomena.

[0148] Among these phenomena, one can observe a change in the position of the bandwidth, a variation in the wavelength of reflection, or a modification of the transmission or reflection peak.

[0149] In addition, a shift in the resonance wavelength, a variation in transmission, or an induced phase change may be observed.

[0150] Finally, it should be emphasized that these phenomena occur depending on environmental conditions or an analyte control parameter.

[0151] Thus, the spectral response of the integrated optical element 130 adapts to changes in the analyte environment or to variations in its properties.

[0152] Sixth embodiment: diversity of physico-chemical parameters measurable by the photonic device

[0153] In a sixth embodiment of the photonic device 100, the physico-chemical parameter of the analyte can be selected from a wide range of options.

[0154] First, the photonic device 100 can measure physical parameters such as temperature, deformation, stress, pressure, torque, vibration or an acoustic wave.

[0155] In addition, the photonic device 100 is capable of detecting fields, including a magnetic field or an electric field.

[0156] Furthermore, the photonic device 100 can also analyze chemical and biological parameters. Thus, it can detect the presence of a biological substance, a chemical product, or even monitor a biochemical reaction.

[0157] In addition, the photonic device 100 is capable of identifying specific molecules such as drugs or proteins.

[0158] Finally, the photonic device 100 offers the possibility of measuring a combination of these different physico-chemical parameters, allowing a more complete and complex analysis of the analyte.

[0159] Multi-parameter analysis system combining photonic device and signal processing processor

[0160] As illustrated in [Fig.2], a second aspect of the invention relates to a multi-parametric analyte analysis system 200, the system comprising two main components: at least one photonic device 100 as described above, and at least one signal processing processor 210.

[0161] In particular, system 200 is designed to determine all or part of the composition of the analyte as well as at least one of its physicochemical properties.

[0162] The term "analyte composition" means all or part of the chemical or biological constituents that form the sample analyzed by the 200 multiparameter analysis system.

[0163] By way of example, the term "analyte composition" may refer to the concentration of different proteins in a blood sample, the proportion of various organic compounds in a complex solution, the presence and quantity of specific biomarkers in a biological tissue, or the isotopic composition of a gaseous sample.

[0164] To do this, the system 200 uses the capabilities of the photonic device 100 in conjunction with the functionalities of the signal processing processor 210.

[0165] The term "signal processing processor" refers to a specialized electronic component of the system 200 that is designed to analyze and interpret the raw data generated by the photonic device 100. The signal processing processor 210 plays a central role in extracting relevant information from spectroscopic signals and changes in spectral response.

[0166] By way of example, the term "signal processing processor" may include a microprocessor dedicated to processing Raman signals for the identification of molecules, a digital signal processor (DSP) optimized for real-time analysis of fluorescence spectra, a system on chip (SoC) integrating spectral deconvolution algorithms, or a tensor computing unit for the application of machine learning methods to spectroscopic data.

[0167] In practice, the signal processing processor 210 performs at least two main tasks.

[0168] First, the signal processing processor 210 processes the initial information relating to the physicochemical parameter of the analyte. In this process, the processor detects changes in all or part of the spectral response of the integrated optical element with variable spectral response 130.

[0169] The term "changes" refers to the measurable and quantifiable modifications of the optical properties of the spectrally variable response integrated optical element 130 in response to variations in the physicochemical parameters of the analyte. These changes manifest themselves as specific alterations in the spectral response of the element, thus allowing the indirect determination of the characteristics of the analyte.

[0170] By way of example, the term "changes" may refer to the shift in the resonance wavelength of a Bragg grating in response to a change in the temperature of the analyte, the change in the transmission of an interference filter due to a change in pressure in the environment of the analyte, or the alteration of the optical phase in a Mach-Zehnder interferometer caused by a fluctuation in the concentration of the analyte.

[0171] Next, the signal processing processor 210 applies the principles of refractometry to these changes to determine the value of the physicochemical parameter of the analyte.

[0172] The term "principles of refractometry" refers to the methods and techniques used to measure and interpret changes in the refractive index of a medium, which are directly related to the physicochemical properties of the analyte. In the context of system 200, these principles are applied by the signal processing unit 210 to determine the value of the physicochemical parameter of the analyte from the changes observed in the spectral response of the integrated optical element.

[0173] By way of example, the term "principles of refractometry" may include the analysis of resonance peak shifts in an integrated Bragg grating to measure the concentration of a solution, the interpretation of phase changes in a Mach-Zehnder interferometer to detect temperature variations, the study of coupling changes in a ring resonator to track biochemical reactions, or the exploitation of transmission variations of an integrated microresonator to measure the adsorption of molecules on its surface.

[0174] In parallel, the signal processing processor 210 processes the spectroscopic signal collected and modified by the integrated optical element with variable spectral response 130, using known techniques.

[0175] The term "known techniques" means scientific and technological methods, processes or approaches that are already established, documented and widely used in the field of integrated spectroscopy and the analysis of physicochemical parameters.

[0176] By way of example, the term "known techniques" may refer to classical Raman spectroscopy methods for molecular identification, standard absorption spectroscopy procedures for concentration measurement, or conventional fluorescence spectroscopy approaches for protein structure analysis.

[0177] The objective of the processing of the collected and modified spectroscopic signal is to obtain at least one second piece of information relating to the composition of the analyte.

[0178] The term "second information" refers to a set of additional data or measurements obtained by the photonic device 100, in addition to the first information relating to the physicochemical parameter of the analyte. This second information enriches the analysis by providing additional data on the analyte or its environment.

[0179] By way of example, the term "second information" may include data on the kinetics of a chemical reaction deduced from temporal changes in the spectrum, information on molecular structure obtained from the analysis of vibrational modes, or measurements of the polarization of scattered light indicating the orientation of molecules in the sample.

[0180] Thus, the 200 system combines the analysis of the physico-chemical properties and the composition of the analyte, offering a complete multi-parametric approach.

[0181] First embodiment: compensation of the wavelength shift by the signal processing engine

[0182] In a first embodiment of the system 200, the signal processing processor 210 is designed to compensate for the wavelength shift of the spectroscopic signal.

[0183] The term “compensate” in the context of system 200 refers to the action of the signal processing unit 210 aimed at correcting or neutralizing the undesirable effects of the wavelength shift of the spectroscopic signal. This compensation makes it possible to maintain the accuracy of spectroscopic measurements despite variations in the optical excitation signal.

[0184] By way of example, the term "compensate" may refer to the application of a spectral correction algorithm that realigns the peaks of the Raman spectrum to their theoretical positions, the use of a dynamic lookup table that adjusts the interpretation of fluorescence data according to the actual excitation wavelength, the implementation of an adaptive normalization technique that eliminates the effects of laser source drift on absorption measurements, or the use of a predictive mathematical model that anticipates and corrects spectral distortions induced by fluctuations in the excitation wavelength.

[0185] The term "spectroscopic signal wavelength shift" refers to the phenomenon whereby the spectral features of the measured signal (such as peaks or bands) are displaced from their expected or reference positions. This shift is directly related to variations in the wavelength of the optical excitation signal and can affect the correct interpretation of spectroscopic data.

[0186] By way of example, the term "spectroscopic signal wavelength shift" may include the displacement of Raman lines from their reference position due to thermal drift of the excitation laser, the change in the position of fluorescence emission bands resulting from a fluctuation in the excitation wavelength, the change in the shape and position of absorption peaks in an infrared spectrum caused by instability of the light source, or the shift of interference fringes in an interferometric detection system due to variations in the wavelength of the source.

[0187] This wavelength shift of the spectroscopic signal is caused by a change in the wavelength of the optical excitation signal.

[0188] Thus, the signal processing processor 210 adjusts the data to take this variation into account.

[0189] The term “adjustment” refers to the process by which the signal processing unit 210 modifies or recalculates the raw spectroscopic information to account for the observed wavelength shift. This adjustment aims to restore the correspondence between the measured data and the expected or calibrated values, thereby ensuring the accuracy of the spectroscopic analysis.

[0190] By way of example, the term "adjust" may include the numerical reassignment of spectral values ​​to their corrected wavelength positions, the application of a transformation function that compensates for the non-linearity induced by the source shift, the dynamic scaling of spectral intensities to maintain the consistency of quantitative measurements, or the use of an adaptive deconvolution algorithm that separates superimposed spectral contributions by taking into account variations in the excitation wavelength.

[0191] Thanks to this compensation, the system 200 can maintain the accuracy of its spectroscopic measurements, despite changes in the wavelength of the optical excitation signal.

[0192] Second embodiment: methods for correcting the wavelength shift - real-time correction and digital post-processing

[0193] In a second embodiment of the system 200, the signal processing processor 210 uses at least one of two correction methods.

[0194] The first method is a real-time correction, in which the signal processing unit 210 instantly adjusts the data to compensate for the wavelength shift as the acquisition progresses. This approach allows for immediate adaptation to changes in measurement conditions, thus ensuring consistent accuracy of the spectroscopic results.

[0195] By way of example, this real-time correction may refer to the continuous adjustment of the spectral calibration as a function of temperature variations of the excitation laser, the dynamic compensation of the effects of drift of the excitation wavelength on a Raman spectrum being acquired, the live adaptation of the signal processing parameters to maintain the alignment of the fluorescence peaks, or the active modulation of the response of an integrated optical filter to follow the rapid fluctuations of the light source.

[0196] In practice, this correction is adapted to the physicochemical dynamics of the analyte, that is, to the temporal changes in the physical and chemical properties of the sample analyzed. This dynamic can influence the spectral response and requires continuous adaptation of the correction process.

[0197] By way of example, the term "analyte physico-chemical dynamics" may include variations in the concentration of a chemical species during a reaction, changes in the viscosity of a solution as a function of temperature, the evolution of the molecular structure of a protein during its folding, or changes in the optical properties of a material under the effect of an applied electric field.

[0198] Furthermore, this correction takes into account the performance of the integrated optical element with variable spectral response 130, namely, its operational characteristics and its ability to modify its spectral response according to the measurement conditions and properties of the analyte. These performance characteristics directly influence the accuracy and sensitivity of the detection system.

[0199] By way of example, the term "the performance of the integrated optical element with variable spectral response 130" may include the range of wavelengths over which the element can be tuned, the speed of response to a change in condition, the achievable spectral resolution, or the stability of the spectral response in the face of variations in temperature or pressure.

[0200] The second method that the signal processing processor 210 can employ is digital post-processing.

[0201] The term "digital post-processing" refers to all the mathematical and algorithmic operations applied to spectroscopic data after their complete acquisition. This approach allows for in-depth analysis and more sophisticated correction of wavelength shifts, using all available information.

[0202] By way of example, the term "digital post-processing" may include the application of spectral deconvolution algorithms to separate the contributions of different chemical species, the use of multivariate regression techniques to correct matrix effects on spectra, the implementation of machine leaming methods to identify and compensate for spectral artifacts, or the use of Fourier transforms to improve spectral resolution and correct phase shifts.

[0203] This approach makes it possible to correct the wavelength shift after data acquisition.

[0204] Digital post-processing may include several complementary steps to improve the quality and accuracy of spectroscopic results.

[0205] First, background noise suppression proves particularly useful for compensating for instabilities in excitation sources, such as in the case of unstable laser diodes, thereby improving the signal-to-noise ratio.

[0206] Next, the measurement of the free spectral range (FSR) can be carried out by scanning two resonances, which provides additional information on the characteristics of the optical system and improves the accuracy of the wavelength shift correction.

[0207] Finally, comparing spectra acquired with different excitations offers a robust method for isolating and correcting artifacts related to fluctuations in the excitation source or variations in experimental conditions. This technique makes it possible to compensate for variations in the system by analyzing the differences between two spectra obtained under distinct excitation conditions.

[0208] Third embodiment: operating mode without calibration of the signal processing processor

[0209] In a third embodiment of the system 200, the signal processing unit 210 is designed to operate in a calibration-free mode that establishes a correspondence between the measured signals and known reference values ​​of the physicochemical parameter of the analyte. This step normally allows for obtaining absolute quantitative measurements. The calibration-free mode offers an alternative to this traditional process.

[0210] By way of example, the term "calibration" may refer to the establishment of a calibration curve relating the intensity of a specific Raman peak to the concentration of a molecule in the analyte, the determination of the relationship between the shift of an optical resonance and the temperature of the sample, the correlation between the fluorescence decay time and the pH of a solution, or the correlation between the width of an absorption band and the viscosity of a fluid.

[0211] In this operating mode, the signal processing processor 210 provides relative values ​​of the physico-chemical parameter of the analyte.

[0212] The term "relative values ​​of the physicochemical parameter of the analyte" refers to measurements that indicate changes or differences in the parameter of interest, rather than its absolute value. These relative values ​​allow for monitoring variations in the parameter without requiring a pre-established absolute reference.

[0213] By way of example, the term "relative values ​​of the physicochemical parameter of the analyte" may include the percentage increase in the concentration of an analyte from its initial state, the rate of change in the temperature of a sample over time, the magnitude of the change in the refractive index of a solution upon the addition of a reagent, or the difference in the partial pressure of a gas between two measurement points in a system. These relative values ​​provide valuable information on the dynamics and trends of the parameter under study, even in the absence of an absolute measurement scale.

[0214] Thus, the 200 system can perform measurements without requiring prior calibration.

[0215] Thanks to this calibration-free operation capability, the System 200 offers increased flexibility in its use. Indeed, it can provide useful information on the relative variations of the analyte's physicochemical parameter, even in the absence of absolute calibration.

[0216] Fourth embodiment: calibration processor and conversion of relative values ​​into absolute measurements

[0217] In a fourth embodiment of the system 200, the calibration processor 220 (e.g. structurally similar to the signal processing processor 210) is designed to establish a correspondence between two elements.

[0218] On the one hand, the calibration processor 220 considers a specific spectral position of the integrated optical element with variable spectral response 130.

[0219] The term “specific spectral position of the integrated optical element with variable spectral response” refers to a particular characteristic in the response spectrum of the optical element 130, which varies predictably and quantifiably as a function of changes in the physicochemical parameter of the analyte. This spectral position serves as a reference point for the calibration of the system 200.

[0220] By way of example, the term "specific spectral position of the integrated optical element with variable spectral response" may refer to the resonance wavelength of a ring resonator which moves according to the refractive index of the analyte, the position of the peak of maximum transmission of an interference filter which varies with the temperature of the sample, the inflection point in the dispersion curve of a waveguide which changes according to the concentration of a chemical species, or the cutoff frequency of a photonic crystal which changes under the effect of an electric field applied to the analyte.

[0221] On the other hand, the calibration processor 220 takes into account a known value of the physico-chemical parameter of the analyte.

[0222] In addition to this calibration function, the signal processing unit 210 is further designed to convert relative values ​​of the physicochemical parameter of the analyte into absolute values.

[0223] The term “absolute values” refers to the precise and directly interpretable quantitative measurements of the physicochemical parameters of the analyte, obtained after conversion of the relative values ​​by the signal processing unit 210, using the calibration established by the calibration unit 220. These absolute values ​​represent specific and standardized quantities, independent of particular measurement conditions or system variations. The absolute values ​​provide an accurate and comparable characterization of the analyte, enabling rigorous quantitative analysis.

[0224] By way of example, the term "absolute values" may refer to the precise concentration of a protein expressed in milligrams per milliliter (mg / mL) in a biological solution, determined from the intensity of a specific Raman peak. Another example would be the exact measurement of the temperature of a sample in degrees Celsius, calculated from the resonance wavelength shift of an integrated optical element.

[0225] Absolute values ​​can also include the precise determination of the pH of a complex chemical solution, with a resolution of two decimal places, based on the change in the spectral response of an integrated optical indicator. A fourth example could be the exact quantification of the partial pressure of a gas in a reaction chamber, expressed in pascals, deduced from changes in the transmission properties of a pressure-sensitive optical waveguide.

[0226] The use of absolute values ​​in this system allows for direct comparison between different measurements, independent of variations in the photonic device 100 or experimental conditions. This facilitates the standardization of results and improves the reliability and reproducibility of spectroscopic analyses in various scientific and industrial applications.

[0227] To perform this conversion, the signal processing processor 210 uses the calibration established by the calibration processor 220.

[0228] Thus, the system 200 can provide absolute measurements of the physicochemical parameter of the analyte, in addition to the relative values ​​mentioned above.

[0229] The term "absolute measurements of the physicochemical parameter of the analyte" refers to the precise and directly interpretable quantitative values ​​of the parameter of interest, obtained through calibration established by the calibration processor 220. These absolute measurements allow for an exact and comparable characterization of the analyte, independent of specific measurement conditions.

[0230] By way of example, the term "absolute measurements of the physicochemical parameter of the analyte" may include the determination of the exact concentration of a protein in mg / mL in a biological solution, the precise measurement of the temperature in degrees Celsius of a fluid sample, the quantification of the pH to two decimal places of a complex chemical solution, or the exact evaluation of the pressure in pascals of a gas in a reaction chamber. These absolute measurements provide standardized and comparable information between different experiments or measurement systems.

[0231] Method for the simultaneous acquisition of spectroscopic signals and physicochemical information of the analyte

[0232] As illustrated in [Fig.3], a third aspect of the invention relates to a method 300 which aims at the simultaneous acquisition of at least one spectroscopic signal of interest of an analyte and at least one first piece of information enabling the determination of at least one physico-chemical parameter of the analyte.

[0233] The process 300 begins with the provision 310 of at least one photonic device 100 as described above.

[0234] Next, the tunable optical source 110 generates 320 an optical excitation signal at least one emission wavelength.

[0235] Once the signal is generated, the method 300 initially aligns the wavelength of the optical excitation signal with at least one predetermined spectral characteristic of the integrated optical element with variable spectral response 130.

[0236] The term “align” in the context of this method 300 refers to the action of precisely matching the wavelength of the optical excitation signal with a specific spectral characteristic of the integrated optical variable response element 130. This alignment optimizes the sensitivity and accuracy of spectroscopic measurements.

[0237] By way of example, the term "align" may refer to adjusting the wavelength of a tunable laser to coincide with the maximum transmission of an integrated optical filter, synchronizing the excitation frequency with the resonance of a ring microresonator, adjusting the emission wavelength to match the inflection point of the response curve of an integrated microresonator, or adapting the wavelength of the excitation signal to maximize the coupling efficiency with an integrated Bragg grating.

[0238] Then, the analyte is irradiated 340 with the optical excitation signal.

[0239] Subsequently, the spectroscopic sensor on chip 120 collects 350 a spectroscopic signal scattered by the analyte.

[0240] After this collection, the integrated optical element with variable spectral response 130 eliminates 360 a residual optical signal from the collected spectroscopic signal having the same wavelength as the excitation optical signal. This step generates a collected and modified spectroscopic signal comprising the spectroscopic signal of interest having wavelengths different from that of the excitation optical signal.

[0241] From this collected and modified spectroscopic signal, the process 300 acquires 370 a first spectroscopic signal of interest of the analyte.

[0242] Subsequently, it detects 380 a misalignment between the wavelength of the optical excitation signal and the predetermined spectral characteristic of the integrated optical element with variable spectral response 130, due to a change in the physicochemical parameter of the analyte.

[0243] The term "misalignment" refers to the loss of correspondence between the wavelength of the optical excitation signal and the predetermined spectral characteristic of the integrated optical element with variable spectral response 130. This misalignment occurs due to changes in the physicochemical parameters of the analyte, which modify the optical properties of the integrated optical element with variable spectral response 130. The detection and correction of this misalignment are important to maintain the accuracy of the measurements throughout the analysis.

[0244] By way of example, the term "misalignment" may include the shift between the excitation wavelength and the resonance peak of a microresonator due to a temperature change of the analyte, loss of synchronization between the laser frequency and the transmission band of an interference filter caused by a pressure variation, shift between the excitation wavelength and the optimal position on the dispersion curve of a waveguide following a change in analyte concentration, or divergence between the excitation signal wavelength and the resonance condition of a photonic crystal induced by a change in the electric field applied to the sample.

[0245] To correct this misalignment, the method 300 adjusts 390 the wavelength of the optical excitation signal to realign it with the predetermined spectral characteristic of the integrated optical element with variable spectral response 130.

[0246] Finally, the process 300 acquires 391 the first information relating to the physico-chemical parameter of the analyte as a function of the change in all or part of the spectral response of the optical element integrated with variable spectral response 130.

[0247] First embodiment: selection of misalignment by measuring the transmission of the optical excitation signal

[0248] In a first embodiment of the method 300, it includes a step of detecting 380 the misalignment between the wavelength of the optical excitation signal and the predetermined spectral characteristic of the integrated optical element with variable spectral response 130.

[0249] This misalignment detection step 380 involves a specific measurement. More precisely, the method 300 measures the transmission of the optical excitation signal, the transmission measurement being carried out through the integrated optical element with variable spectral response 130.

[0250] The term "measurement" means the action of accurately and reproducibly quantifying the transmission of the optical excitation signal through the integrated optical element with variable spectral response 130. This action involves determining the light intensity of the optical excitation signal before and after its passage through the optical element, thus allowing the evaluation of changes in the transmission properties of this element.

[0251] By way of example, the term "measure" may refer to the determination of the attenuation of the optical excitation signal by an integrated Bragg grating which varies with the temperature of the analyte, the quantification of the intensity modulation of the signal passing through a ring resonator whose properties change with the concentration of the analyte, or the evaluation of the phase variations of the optical signal in an integrated Mach-Zehnder interferometer which reacts to changes in the pressure of the analyte.

[0252] Measuring the transmission of the optical excitation signal provides information on the state of alignment between this signal and the spectral characteristics of the element optical. This information is used to detect and quantify misalignments, which are indicative of changes in the physicochemical parameters of the analyte. The measurement process typically involves the use of integrated optical detectors that convert light intensity into measurable electrical signals.

[0253] Thus, the method 300 uses the transmission properties of this element to detect any misalignment.

[0254] By analyzing the variations in the transmission of the optical excitation signal through the spectrally variable response integrated optical element 130, the method 300 can precisely identify misalignments. This approach allows for the fine detection of changes in the physicochemical parameters of the analyte.

[0255] Second embodiment: calibration step for the precise conversion of spectral changes into values ​​of the physico-chemical parameter of the analyte

[0256] In a second embodiment of the process 300, it includes a calibration step 392 which comprises at least two main actions.

[0257] First, it establishes a correspondence between two elements.

[0258] On the one hand, it considers at least one predetermined spectral characteristic of the integrated optical element with variable spectral response 130.

[0259] On the other hand, it takes into account at least one known value of the physico-chemical parameter of the analyte.

[0260] Second, the calibration step 392 uses the established correspondence for a specific conversion. More precisely, it converts the change in all or part of the spectral response of the integrated optical element with variable spectral response 130 into a value of the physicochemical parameter of the analyte.

[0261] This conversion takes place during the acquisition of the first information.

[0262] The term "conversion" refers to the mathematical transformation process that translates the observed change in the spectral response of the spectrally variable optical element 130 into a quantitative and meaningful value for the physicochemical parameter of the analyte. This conversion relies on a previously established correspondence between the spectral characteristics of the optical element and known values ​​of the physicochemical parameter. The conversion process uses this correspondence to interpret the raw spectral data and transform them into directly usable information about the analyte.

[0263] By way of example, the term "conversion" may refer to the transformation of the wavelength shift of a Bragg grating into a precise measurement of the analyte temperature, the interpretation of the change in transmission of a ring resonator in terms of the concentration of a specific molecule in the analyte, or the translation of the phase shift observed in a Mach-Zehnder interferometer into a pressure value of the gaseous analyte.

[0264] Conversion plays a central role in acquiring initial information about the physicochemical parameters of the analyte. It allows the transformation from raw optical data to calibrated and precise measurements of the analyte's properties. This conversion process ensures that the observed spectral changes are interpreted consistently and reproducibly, thus providing reliable and quantitative results on the physicochemical characteristics of the analyte under study.

[0265] Thus, process 300 can provide calibrated and accurate values ​​of the physico-chemical parameter of the analyte.

[0266] Third embodiment: step of correcting the second spectroscopic spectrum based on the physico-chemical parameters of the analyte

[0267] In a third embodiment of the process 300, it includes an acquisition step 393 of a second spectroscopic signal of interest of the analyte from the collected and modified spectroscopic signal, with the wavelength of the optical excitation signal realigned and a correction step 394 which follows the acquisition of the second spectroscopic signal of interest of the analyte.

[0268] More specifically, this step corrects the second spectroscopic spectrum, that is, it applies a mathematical and algorithmic adjustment to the second spectroscopic spectrum using the information obtained on the physicochemical parameter of the analyte. This correction aims to compensate for the effects of variations in the physicochemical properties of the analyte on the spectroscopic signal, thereby improving the accuracy and reliability of the results.

[0269] In practice, the correction step 394 of the second spectroscopic spectrum is carried out according to the first information acquired which relates to the physicochemical parameter of the analyte.

[0270] In particular, the correction step 394 involves a series of signal processing operations which take into account changes in the analyte environment to refine the interpretation of the spectrum.

[0271] By way of example, the term "correction" may refer to adjusting the relative intensities of Raman peaks as a function of the sample temperature, allowing for more precise quantification of the chemical species present. Another example would be compensating for the effects of pressure on the width of absorption lines, thereby improving the determination of gas concentration in a complex mixture.

[0272] The correction step 394 may also include normalizing the fluorescence spectrum to account for variations in the pH of the solution, thus enabling better comparison between different samples or experimental conditions. A fourth example could be the elimination of spectral artifacts induced by changes in viscosity in a fluid, ensuring a more reliable analysis of molecular interactions in complex biological systems.

[0273] Thus, process 300 uses the data obtained on the physicochemical parameter to refine and adjust the second spectroscopic spectrum. This approach potentially improves the accuracy and reliability of the spectroscopic results.

[0274] This correction step 394 makes it possible to obtain spectroscopic results that accurately reflect the composition and properties of the analyte, independent of fluctuations in experimental conditions. It allows for the full exploitation of the information contained in the spectrum, taking into account the complex interactions between the physicochemical parameters and the spectral response of the sample.

[0275] In this particular embodiment of the third embodiment, the correction step 394 uses the excitation-shifted differential Raman spectroscopy (ERSDS) technique. This method involves acquiring two Raman spectra with slightly different excitation wavelengths, followed by subtraction of these spectra. The use of ERSDS offers two major advantages. First, it allows for the efficient decoupling of the Raman signal from the fluorescence signal, thereby improving the quality and specificity of the obtained Raman spectra. Second, it offers the possibility of averaging over several pixels the quantum efficiency variations of the spectrometer pixels, thus reducing detector-related artifacts.

[0276] It is important to note that this technique provides significant added value even in the absence of information on the physicochemical parameters of the analyte. Indeed, SERDS intrinsically improves the quality of Raman spectra by eliminating fluorescence interference and reducing the effects of detector efficiency variations.

[0277] In practice, the 300 method acquires a first spectrum with an initial excitation wavelength, and then a second spectrum with a slightly shifted excitation wavelength. Subtracting these two spectra yields a differential spectrum that highlights the Raman features while suppressing fluorescence contributions and other spectral interferences. This approach significantly enhances the device's ability to isolate and analyze specific Raman signals, even in complex samples exhibiting strong fluorescence or other spectral interferences.

[0278] Conclusion

[0279] We have described and illustrated the invention. However, the invention is not limited to the embodiments we have presented. Indeed, numerous combinations of variants, alternatives, embodiments, and implementations can be envisaged without requiring substantial modifications to the invention. Thus, a field expert can deduce other variants, alternatives, embodiments, and implementations from the description and accompanying figures, taking into account the economic, ergonomic, and dimensional constraints to be respected.

[0280] For example, in a first embodiment, the photonic device 100 is designed as a single, integrated entity, where all the constituent elements are incorporated on a single chip.

[0281] The term "chip" means a single semiconductor substrate, generally made of silicon, on which all the optical and electronic components of the photonic device 100 are manufactured and interconnected. This chip serves as a monolithic integration platform for all the functional elements of the device.

[0282] By way of example, the term "chip" may refer to a silicon-on-insulator (SOI) photonic integrated circuit (PIC) which combines on the same substrate the tunable optical source 110, the integrated spectroscopic sensor 120, the integrated optical element with variable spectral response 130, as well as the waveguides and optical interconnections required.

[0283] This integrated and unique configuration differs from previously described embodiments, where the various elements of the photonic device 100 could be distributed across several separate substrates or components. Complete integration onto a single chip offers several advantages, including significant miniaturization, reduced optical losses between components, and a potential improvement in overall system performance.

[0284] In practice, this monolithic integration makes it possible to optimize the interactions between the different elements of the photonic device 100, thus facilitating the simultaneous and precise acquisition of spectroscopic data and physicochemical information of the analyte.

[0285] In a second particular embodiment, the signal processing processor 210 is designed to perform multiplexing and synchronized processing of signals from a plurality of spectroscopic sensors, so as to obtain a multi-parametric characterization of the analyte.

[0286] “Multiplexing” refers to the ability of the signal processing unit 210 to simultaneously handle data from several spectroscopic sensors, each of which can be dedicated to a specific type of analysis or a particular spectral range. This approach provides a more complete overview of the analyte's properties.

[0287] “Synchronized processing” refers to the processor's ability to coordinate the acquisition and analysis of data from different sensors, taking into account the temporal relationships between the different signals. This synchronization is essential to establish accurate correlations between the different parameters measured.

[0288] The resulting "multi-parametric characterization" offers a richer and more detailed analysis of the analyte, enabling simultaneous acquisition of information on its chemical composition, molecular structure, and physical properties, all with high temporal resolution.

[0289] Thus, the second particular embodiment illustrates the ability to simultaneously integrate and analyze data from different spectroscopic modalities, thereby providing a more complete and detailed view of the analyte properties.

[0290] By way of example, this functionality may include the synchronization and joint analysis of Raman and fluorescence signals for a more complete characterization of complex molecules, the integration of absorption and scattering data for a better understanding of the optical properties of nanoparticles, or the combination of spectroscopic measurements and refractometry data for a simultaneous analysis of the chemical composition and physical properties of a complex fluid.

[0291] In a third particular embodiment, the invention uses a ring resonator as an integrated optical element with variable spectral response 130, in particular to simultaneously perform two functions: optical filtering and temperature measurement.

[0292] The ring resonator is an integrated optical structure consisting of a waveguide forming a closed loop, coupled to one or more linear waveguides. Its operating principle is based on the constructive interference of light circulating in the ring, which only occurs for certain specific wavelengths, called resonance wavelengths.

[0293] As an optical filter, the ring resonator allows for the precise selection of desired wavelengths for Raman or fluorescence analysis, for example, while effectively rejecting spurious signals. Its spectral response can be finely tuned by modifying the geometric parameters of the ring, thus offering great flexibility in filter design. Simultaneously, the ring resonator serves as an extremely sensitive temperature sensor. Temperature variations in the surrounding medium slightly alter the refractive index of the ring material, resulting in a measurable shift in the resonance wavelengths. By precisely monitoring this shift, it is possible to deduce temperature changes with high accuracy.

[0294] The use of a ring resonator for these two functions has several advantages.

[0295] First, its compact size optimizes space utilization on the chip, with a single structure fulfilling two roles. Furthermore, ring resonators offer excellent sensitivity for both filtering and temperature sensing. Their ease of integration makes them compatible with standard silicon photonics fabrication processes. Finally, their tunability allows for dynamic adjustment of the resonator's response, providing real-time adaptation to measurement conditions.

[0296] The processing of raw data acquired by the System 200 involves sophisticated algorithms to accurately extract Raman or fluorescence and temperature information. These algorithms ensure the reliability and accuracy of the measurements. The extraction of Raman or fluorescence information comprises several steps. Signal preprocessing includes background noise removal, baseline correction, and spectral normalization, using techniques such as Savitzky-Golay smoothing and the Sensitive Nonlinear Iterative Peak (SNIP) method to improve signal quality. Spectral deconvolution then separates individual Raman or fluorescence peaks using algorithms such as nonlinear least squares or the Levenberg-Marquardt algorithm, allowing the identification and quantification of the different chemical components present in the sample.Finally, chemometric analysis applies multivariate analysis techniques such as principal component analysis (PCA) or partial least squares regression (PLS) to extract quantitative and qualitative information on the chemical composition of the sample.

[0297] For extracting temperature information, the process includes detecting resonance peaks to precisely identify the spectral position of the ring resonator's resonance peaks, real-time spectral shift monitoring to measure the shift in the resonance wavelength relative to a calibrated reference value, and temperature conversion where the measured spectral shift is converted into a temperature variation using a transfer function previously established during sensor calibration. An integration algorithm ensures the synchronization of the Raman or fluorescence data and the temperature data, and cross-correction is applied to account for the influence of temperature on the Raman or fluorescence signal, thereby improving the overall accuracy of the measurements.

[0298] System 200 is designed to efficiently manage potential interference between Raman or fluorescence measurement and temperature measurement, while optimizing their simultaneous operation. This management relies on several strategies, including spectral separation, time-division multiplexing, and signal processing. Advanced cross-calibration is supported. The ring resonator used for temperature measurement is designed to operate at a different wavelength than that used for Raman or fluorescence excitation. This spectral separation minimizes direct interference between the two measurements. The System 200 can use a tunable laser to rapidly switch between Raman or fluorescence measurement and temperature measurement. This switching occurs at a sufficiently high frequency that the two measurements appear simultaneous on the timescale of the observed biological processes.

[0299] In one example, the cointegration of the temperature sensor and the spectroscopic sensor on-chip 120 with a signal filtering function at the input and output of the spectroscopic sensor on-chip 120 requires the use of a single 2x2 coupler used as a spectral filter for the spectroscopic sensor on-chip 120 and as a second sensor, whose spectral response varies with temperature. The parallel measurement of the Raman or fluorescence spectrum, the filtering, and the temperature measurement of the medium require the use of a tunable laser. This type of laser allows the excitation wavelength at the chip input to be adjusted to scan a wavelength range. This scan makes it possible to measure the shift in the ring's resonance wavelength and thus deduce the temperature while maintaining the Raman or fluorescence measurement.

[0300] To vary the wavelength of a tunable laser, the value of the current applied to it to trigger the laser effect (called the polarization current) is varied. The laser's tunability is chosen according to the desired scan accuracy and the position of the filter used. To perform the temperature measurement, it is first necessary to characterize the spectral response of the filter (resonator) alone, as well as the variation of its wavelength response as a function of temperature and its sensitivity to this variation. From these measurements, the relationship between the temperature variation and the variation of the filter's central wavelength can be deduced, and thus the temperature sensor can be calibrated.

[0301] For example, in the article "Ultra-sensitive chip-based photonic temperature sensor using ring resonator structures" (Opt. Express 22, 3098-3104, 2014), Haitan Xu et al. present the dependence of the resonance wavelength on the temperature for a ring resonator.

[0302] According to their analysis, this dependence can be expressed by the equation: Xm = [neff(Xm,T) x L(T)] / m, where Xm is the resonance wavelength in vacuum, neff the effective index of the waveguide, m the optical mode number, T the temperature and L the perimeter of the ring.

[0303] The authors then derive the temperature-induced wavelength shift: AXm = [(dneff / dT + neff(dL / dT)( 1 / L)) / ng] x (AT x Xm), where ng is the group index defined by ng = (neff - Xm(dneffÆ)Xm)).

[0304] They note that for silicon, the thermo-optical effect (dneff / dT ~ 2 x 10A-4 / K) dominates largely compared to thermal expansion (3.57 x 10A-6 / K).

[0305] In their study, Xu et al. demonstrated a thermal sensitivity of 77 pm / K for a silicon ring resonator with a diameter of 11 pm and a quality factor of 52000. This sensitivity is approximately eight times greater than that of fiber Bragg grating temperature sensors. Using a side-of-fringe, constant-power mode measurement method, they were able to detect temperature differences as small as 80 pK, representing a thirteen-fold improvement over the traditional wavelength-scanning method.

[0306] In a fourth particular embodiment, the photonic device 100 uses a fixed wavelength optical source in combination with an integrated optical element with variable spectral response 130 that is tunable.

[0307] In this configuration, the tunable optical source 110 is replaced by a fixed-wavelength laser source. The integrated variable spectral response optical element 130 is designed to be adjustable, allowing alignment with the fixed wavelength of the laser to be maintained after variations induced by changes in the physicochemical parameter of the analyte.

[0308] The operation of this embodiment begins with the initial alignment of the variable spectral response integrated optical element 130 with the fixed wavelength of the laser. When changes in the physicochemical parameters of the analyte occur, they induce a variation in the spectral response of the integrated optical element 130. To compensate for this variation, the integrated optical element 130 is adjusted to restore its correspondence with the fixed wavelength of the laser. The magnitude of the adjustment required to restore this correspondence provides an indirect measure of the change in the physicochemical parameters of the analyte.

[0309] This approach has several potential advantages, including the simplification of the optical source which no longer needs to be tunable, the possibility of using high stability and precision fixed wavelength lasers, as well as increased flexibility in the design of the integrated optical element with variable spectral response 130. The signal processing processor 210 is adapted to interpret the adjustments of the integrated optical element 130 and deduce the variations of the physico-chemical parameter of the analyte.

[0310] In the description, when an expression uses the term "at least one", this means that the element or feature in question may be present in a single occurrence or in multiple occurrences, thus comprising one, two, three or more elements or features, without any upper limit specified.

[0311] On the other hand, when an element is "designed" to perform a particular function, this means that the element is created specifically for the purpose of performing that particular function. However, depending on the needs and available resources, it may be possible to use an existing element, which will be modified or adapted to perform that particular function, without requiring substantial modifications to the invention.

[0312] As regards the expression "all or part," it indicates flexibility in the selection or use of the elements or data mentioned. This expression means that the action or characteristic described may apply to the entire set of elements or data in question, or only to a selected portion thereof. The use of "all or part" thus allows for a wide range of possibilities, from full to partial use, without specifying a precise lower or upper limit as to the quantity or proportion concerned.

[0313] Furthermore, in the description, when a list of examples is provided, it should not be interpreted as exhaustive. It should be noted that these examples are given by way of illustration and not limitation. Indeed, although specific examples have been presented throughout this description, it is understood that the invention is not limited to these embodiments alone and that other implementations may be considered by a person skilled in the art of the invention.

[0314] Finally, the invention can be the subject of numerous variations and applications other than those described above. In particular, unless otherwise indicated, the various structural and functional features of each particular embodiment described above should not be considered as combined and / or closely and / or inextricably linked to one another, but, on the contrary, as mere juxtapositions. Furthermore, the structural and / or functional features of the various embodiments described above may be the subject, in whole or in part, of any different juxtaposition or any different combination.

Claims

Demands

1. A photonic device (100) for the simultaneous acquisition of at least one spectroscopic signal of interest from an analyte, and at least one first piece of information designed to enable the determination of at least one physicochemical parameter of the analyte, the photonic device (100) comprising an integrated architecture that includes optical components and integrated optical connections linking the optical components, the optical components comprising at least one optical source (110) designed to generate, at at least one emission wavelength, at least one optical signal designed to excite the analyte, referred to as the excitation optical signal, the optical source (110) being either wavelength-tunable or fixed-wavelength, at least one spectroscopic sensor-on-chip (120), and at least one integrated optical element with a variable spectral response (130), wherein, when the optical source (110) is adjustable,This is further designed to adjust the wavelength of the optical excitation signal based on the detection of at least one change in all or part of the spectral response of the integrated variable spectral response optical element (130), so as to maintain constant alignment between the wavelength of the optical excitation signal and at least one predetermined spectral characteristic of the integrated variable spectral response optical element (130); — the optical source (110) has a fixed wavelength; the integrated variable spectral response optical element (130) is further designed to be adjustable so as to maintain constant alignment with the fixed wavelength of the optical excitation signal; — the spectroscopic sensor on-chip (120) is designed to collect the spectroscopic signal that is scattered by the analyte in response to irradiation of the analyte by the optical excitation signal; the collected spectroscopic signal comprising, — a residual optical signal having the same wavelength as the excitation optical signal, and — at least one spectroscopic signal of interest having wavelengths different from that of the excitation optical signal, and — the integrated optical element with variable spectral response (130) is designed such that the variation of its spectral response depends specifically and quantifiably on at least one physicochemical parameter of an analyte, the integrated optical element with variable spectral response (130) being further designed to: — receive the collected spectroscopic signal, — eliminate the residual optical signal from the collected spectroscopic signal, so as to generate a collected and modified spectroscopic signal comprising the spectroscopic signal of interest, and — modify all or part of its spectral response as a function of the physicochemical parameter of the analyte,in order to allow the acquisition of the first information which relates to the physico-chemical parameter of the analyte, the modification being induced by a variation in the permittivity of the material constituting the optical element integrated with variable spectral response (130) in response to the physico-chemical parameter of the analyte.

2. Photonic device (100) according to claim 1, wherein, - the spectroscopic sensor on chip (120) comprises at least one input and at least one output, and - the integrated optical element with variable spectral response (130) is arranged at the input and / or output of the spectroscopic sensor.

3. Photonic device (100) according to any one of claims 1 to 2, wherein the integrated variable spectral response optical element (130), the spectroscopic sensor on chip (120), and the optical source (110) share a common substrate.

4. Photonic device (100) according to any one of claims 1 to 3, wherein the spectroscopic sensor on chip (120) is selected from, - a Raman sensor on chip which is designed to implement waveguide-amplified Raman spectroscopy technology, and - a fluorescence sensor on chip which is designed to implement waveguide-amplified fluorescence spectroscopy technology.

5. A photonic device (100) according to any one of claims 1 to 4, wherein the integrated optical element with variable spectral response (130) is selected from: - a tunable Bragg grating, - a variable coupling ring resonator, - a liquid crystal photonic structure whose refractive index varies with temperature or pressure, - a multilayer interference filter whose bandwidth shifts, - a Mach-Zehnder interferometer, - a silicon-on-insulator (SOI) waveguide, - a silicon nitride waveguide, - an optical fiber integrated into a microfluidic channel, - an integrated diffraction grating, - a directional coupler, - an integrated microresonator, - a photonic crystal, or - any combination thereof, and wherein the variable spectral response of the integrated optical element (130) is manifested by at least one of the following phenomena: - a change in the position of the bandwidth,- a variation in the reflection wavelength, - a modification of the transmission or reflection peak, - a shift in the resonance wavelength, - a variation in transmission, or - an induced phase change, depending on environmental conditions or an analyte control parameter.

6. Photonic device (100) according to any one of claims 1 to 5, wherein the physicochemical parameter of the analyte is selected from: temperature, strain, stress, pressure, torque, vibration, acoustic wave, magnetic field, electric field, biological substance, chemical, biochemical reaction, drug, protein, or a combination thereof.

7. A multi-parametric analysis system (200) for an analyte for the determination of its composition and at least one of its physico-chemical properties, the system (200) comprising: - at least one photonic device (100) according to any one of claims 1 to 6, and - at least one signal processing processor (210) which is designed to: - process the first information relating to the physico-chemical parameter of the analyte to detect changes in all or part of the spectral response of the integrated optical element with variable spectral response (130), then apply the principles of refractometry to all or part of the changes in order to determine the value of the physico-chemical parameter of the analyte, and - process the spectroscopic signal collected and modified by the integrated optical element with variable spectral response (130) to obtain at least a second piece of information relating to the composition of the analyte.

8. System (200) according to claim 7, wherein the signal processing processor (210) is designed to compensate for the wavelength shift of the spectroscopic signal due to the change in wavelength of the optical excitation signal.

9. System (200) according to any one of claims 7 to 8, wherein the signal processing processor (210) is designed to perform wavelength shift correction of the spectroscopic signal according to at least one of the following methods, - a real-time correction adapted to the physicochemical dynamics of the analyte and the performance of the integrated variable spectral response optical element (130), and - a digital post-processing.

10. System (200) according to any one of claims 7 to 9, wherein the signal processing processor (210) is designed to operate in a calibration-free mode providing relative values ​​of the physicochemical parameter of the analyte.

11. System (200) according to any one of claims 7 to 10, further comprising at least one calibration processor (220) which is designed to establish a correspondence between a specific spectral position of the spectral response integrated optical element variable (130) and a known value of the physicochemical parameter of the analyte, and wherein the signal processing processor (210) is further designed to convert relative values ​​of the physicochemical parameter of the analyte into absolute values ​​using the established calibration.

12. A method (300) for the simultaneous acquisition of at least one spectroscopic signal of interest from an analyte and at least one initial piece of information designed to enable the determination of at least one physicochemical parameter of the analyte, the method (300) comprising the following steps: providing (310) at least one photonic device (100) according to any one of claims 1 to 6; generating (320), using the optical source (110), an optical excitation signal at at least one emission wavelength, the optical source (110) being either wavelength-tunable or fixed-wavelength; initially aligning (330) the wavelength of the optical excitation signal with at least one predetermined spectral feature of the integrated variable spectral response optical element (130); and irradiating (340) the analyte with the signal. excitation optics, - collect (350), using the spectroscopic sensor on chip (120),a spectroscopic signal scattered by the analyte, - eliminate (360), using the integrated optical element with variable spectral response (130), a residual optical signal from the collected spectroscopic signal having the same wavelength as the excitation optical signal, so as to generate a collected and modified spectroscopic signal comprising the spectroscopic signal of interest having wavelengths different from that of the excitation optical signal, - acquire (370) a first spectroscopic signal of interest from the analyte from the collected and modified spectroscopic signal, - detect (380) a misalignment between the wavelength of the excitation optical signal and the predetermined spectral characteristic of the integrated optical element with variable spectral response (130) due to a change in the physico-chemical parameter of the analyte, - when the optical source (110) is tunable, adjust (390) the wavelength of the optical excitation signal to realign it with the predetermined spectral characteristic of the optical element integrated with variable spectral response (130), - when the optical source (110) is of fixed wavelength, adjust (390) the optical element integrated with variable spectral response (130) to realign it with the fixed wavelength of the optical excitation signal, and - acquire (391) the first information which is relative to the physico-chemical parameter of the analyte as a function of the change in all or part of the spectral response of the optical element integrated with variable spectral response (130).

13. Method (300) according to claim 12, wherein the misalignment detection step (380) comprises measuring the transmission of the optical excitation signal through the integrated variable spectral response optical element (130).

14. A method (300) according to any one of claims 12 to 13, further comprising a calibration step (392) for: - establishing a correspondence between at least one predetermined spectral characteristic of the integrated variable spectral response optical element (130) and at least one known value of the physicochemical parameter of the analyte, and - using the correspondence to convert the change in all or part of the spectral response of the integrated variable spectral response optical element (130) into a value of the physicochemical parameter of the analyte during the acquisition of the first information.

15. A method (300) according to any one of claims 12 to 14, further comprising - an acquisition step (393) of a second spectroscopic signal of interest of the analyte from the collected and modified spectroscopic signal, with the wavelength of the optical excitation signal realigned, and - a correction step (394) of the second spectroscopic spectrum as a function of the first information which is related to the acquired physico-chemical parameter.

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