In-situ substance component detection equipment and method based on fluorescence spectrum

Abstract

The invention discloses an in-situ substance component detection device and method based on fluorescence spectrum, and aims to solve the problems that the existing spectrum detection device depends on manual sampling for off-line detection, the aging is poor, and the substance change process cannot be dynamically tracked in real time. An APL two-wire system power supply and communication module and a time-sharing multi-wavelength laser light source are adopted to cyclically excite fluorescence characteristics of different substances in the mixed liquid according to a preset sequence; the detection window is in direct contact with a liquid medium, high-temperature and high-pressure working conditions are resisted, in-situ on-line installation of equipment in an industrial pipeline or a reactor is achieved, and sampling and sample pretreatment are not needed.

Description

Technical Field

[0001] This invention belongs to the technical field of spectral detection, and particularly relates to an in-situ material component detection device and method based on fluorescence spectroscopy. Background Technology

[0002] Existing spectroscopic detection equipment relies on large optical components such as gratings, which are bulky and difficult to integrate into industrial pipelines. Therefore, it often requires manual sampling for offline detection, which is not only time-consuming and unable to track the material change process in real time, but also has high labor costs and is prone to sample contamination. In addition, the offline multi-component detection process is cumbersome, often requiring pre-separation and relying on manual detection experience, which is inaccurate. Summary of the Invention

[0003] The purpose of this invention is to provide an in-situ material composition detection device based on fluorescence spectroscopy, which can be installed in industrial pipelines to perform in-situ material composition detection in real time.

[0004] To solve the above problems, the technical solution of the present invention is as follows: An in-situ material composition detection device based on fluorescence spectroscopy, comprising: The pressure-resistant housing integrates the following modules, which are interconnected and work together via an APL two-wire bus: The power supply module is used to simultaneously supply power to the light source module and the spectrum module through the APL two-wire bus, and has a built-in capacitor energy storage unit to maintain voltage stability during the peak power consumption of the light source module. The communication module is connected to the APL two-wire bus of the power supply module and is used to realize wavelength switching control of the light source module, full-spectrum data acquisition of the spectral module and full-duplex data transmission through the APL industrial communication protocol. The light source module consists of multiple laser light sources of specific wavelengths. It emits lasers in a time-division manner according to the switching command of the communication module. The lasers are transmitted to the detection window through the light guide structure to excite the liquid medium to generate a fluorescence signal. The spectral module employs a quantum dot array spectral sensor to receive fluorescence signals transmitted through the light guide structure and convert them into full-spectrum data, which is then uploaded in real time via the communication module. The detection window is fixed at the end of the pressure-resistant housing and is directly immersed in the liquid medium in the industrial pipeline or reactor to achieve physical isolation and optical coupling between the optical path and the measured environment.

[0005] According to one embodiment of the present invention, the wavelength of the laser light source includes 355nm, 405nm and 532nm, which correspond to the fluorescence excitation peaks of different substances.

[0006] According to an embodiment of the present invention, each laser source operates independently in a time-division manner under the synchronous timing control of the communication module. The 355nm laser source is used to excite the fluorescence properties of ethanol, the 405nm laser source is used to excite the fluorescence properties of hexanoic acid, and the 532nm laser source is used to excite the fluorescence properties of ethyl hexanoate. The fluorescence signals generated by each wavelength are transmitted to the spectral module through the light guide structure.

[0007] According to an embodiment of the present invention, the APL two-wire power supply and communication timing control is configured as follows: During the detection phase, the power supply equipment periodically sends detection signals on the twisted pair. When the receiving equipment is not powered on, the line is in a voltage-free state, and the power supply equipment identifies the connection of the receiving equipment by detecting the impedance of the circuit. During the grading phase, after detecting a valid powered device, the power supply equipment sends a grading signal to determine the power level of the powered device, and then closes the power supply switch to output a stable voltage. After receiving the voltage, the powered device enters the wake-up and initialization state. During the link establishment phase, the physical layer chip inside the powered device starts up and continuously sends link pulses to attempt to establish a link with the power supply device. Both parties complete full-duplex initialization through automatic negotiation, and enter the normal communication ready state after successful establishment. During the data communication phase, in each cycle, the power supply equipment provides constant current power to the power receiving equipment through the same pair of cables. At the same time, in the 1ms burst time slot at the end of the cycle, a full-duplex data signal is superimposed on the power supply line to realize the physical layer multiplexing of power supply and communication. During the periodic detection embedding phase, the power supply equipment periodically inserts detection signals to monitor the status of the powered equipment during data communication. Upon receiving the detection signal, the powered equipment sends back a response pulse to ensure the continuous stability of the link.

[0008] According to one embodiment of the present invention, during the data communication phase, when the light source module of the powered device generates peak power consumption at the moment of excitation, the built-in capacitor energy storage unit of the powered device instantaneously discharges to compensate for the current gap, ensuring that the APL bus voltage fluctuation is less than the threshold.

[0009] According to an embodiment of the present invention, during the link establishment phase, the power receiving device and the power supply device use echo cancellation technology to achieve full-duplex communication. Downlink control commands and uplink spectral data are separated in the frequency domain to avoid signal conflicts. The communication module sends a TTL level synchronization pulse at the beginning of each cycle to trigger the light source module to start a new round of wavelength switching.

[0010] According to an embodiment of the present invention, the light guide structure is disposed between the light source module, the spectral module and the detection window, and includes: The light guide column is used to directionally transmit laser and fluorescence signals within a limited space. Its incident end is coupled to the light source module and the spectral module, and its output end is coupled to the detection window. A filter is disposed in the optical path of the light guide post. The filter is a dichroic filter, which is used to transmit a laser of a specific wavelength in the excitation optical path and reflect a fluorescence signal, and to transmit a fluorescence signal in the receiving optical path and block laser leakage. A lens assembly, disposed at both ends of the light guide post, includes a collimating lens and a focusing lens. The collimating lens is used to collimate the diverging laser beam emitted by the light source module into parallel light, and the focusing lens is used to focus the returned fluorescence signal onto the photosensitive surface of the spectral module.

[0011] A method for in-situ quantitative analysis of multi-component substances based on fluorescence spectroscopy, using the equipment in one embodiment of the present invention, includes the following steps: The time-division multi-wavelength excitation step uses a light source module to switch different wavelengths of laser light sources in a preset order to excite the fluorescence properties of each target substance in the mixed liquid. The full-spectrum acquisition step uses a quantum dot array spectral sensor to receive fluorescence signals generated in the time-division multi-wavelength excitation step, generating full-spectrum data covering the range of 350nm~1070nm; The data preprocessing steps involve noise reduction, baseline correction, and normalization of the full-spectrum data to eliminate environmental interference. The component analysis step uses a pre-stored chemometric model to perform real-time analysis on the processed full-spectrum data, and performs nonlinear mapping inversion between spectral intensity and substance concentration to calculate the real-time concentration value of each target component. The data transmission step involves transmitting the calculated concentration data to the external control system in real time via the APL communication module.

[0012] Because the present invention adopts the above technical solution, it has the following advantages and positive effects compared with the prior art: The in-situ material composition detection device based on fluorescence spectroscopy in one embodiment of the present invention addresses the problems of existing spectral detection devices that rely on manual sampling for offline detection, which is not only time-consuming but also unable to dynamically track the material change process in real time. It replaces the traditional grating with a quantum dot array spectral sensor, adopts an APL two-wire power supply and communication module and a time-division multi-wavelength laser light source, and cyclically excites the fluorescence characteristics of different substances in the mixed liquid in a preset sequence. Furthermore, it directly contacts the liquid medium through the detection window, withstands high temperature and high pressure conditions, and enables the device to be installed in-situ online in industrial pipelines or reactors without the need for sampling and sample pretreatment. Attached Figure Description

[0013] Figure 1This is a block diagram of an in-situ material composition detection device based on fluorescence spectroscopy according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a power supply module according to one embodiment of the present invention; Figure 3 This is a power supply and communication timing control diagram according to one embodiment of the present invention; Figure 4 This is a flowchart of fluorescence excitation and signal acquisition in one embodiment of the present invention; Figure 5 This is a flowchart of in-situ material component detection in one embodiment of the present invention. Detailed Implementation

[0014] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a further detailed explanation of the in-situ material composition detection device and method based on fluorescence spectroscopy proposed in this invention.

[0015] Please refer to Figure 1 This embodiment provides an in-situ material component detection device based on fluorescence spectroscopy, comprising: The pressure-resistant housing integrates the following modules, which are interconnected and work together via an APL two-wire bus: The power supply module is used to simultaneously power the light source module and the spectrum module via the APL two-wire bus, and has a built-in capacitor energy storage unit to maintain voltage stability during the peak power consumption of the light source module. The communication module is connected to the APL two-wire bus of the power supply module and is used to realize wavelength switching control of the light source module, full-spectrum data acquisition of the spectral module and full-duplex data transmission through the APL industrial communication protocol. The light source module consists of multiple laser light sources of specific wavelengths. It emits lasers in a time-division manner according to the switching instructions of the communication module. The lasers are transmitted to the detection window through the light guide structure to excite the liquid medium to generate a fluorescence signal. The spectral module uses a quantum dot array spectral sensor to receive fluorescence signals transmitted through the light guide structure and convert them into full-spectrum data, which is then uploaded in real time via the communication module. The detection window is fixed at the end of the pressure-resistant housing and is directly immersed in the liquid medium in the industrial pipeline or reactor to achieve physical isolation and optical coupling between the optical path and the measured environment.

[0016] The testing equipment uses a pressure-resistant housing and integrates a quantum dot array spectral sensor, an APL two-wire power supply and communication module, a time-division multi-wavelength laser light source array, and a detection window. This allows the equipment to be installed in situ in industrial pipelines or reactors without the need for sampling or sample pretreatment. It supports simultaneous quantitative analysis of multiple components, eliminates the pre-separation process and manual sampling, and significantly reduces deployment and maintenance costs.

[0017] For details, please refer to Figure 2 and Figure 3 The power supply module integrates power supply and communication via an APL two-wire system (power supply + data multiplexing). The communication module integrates the APL industrial communication protocol, supporting full-duplex data transmission and meeting the real-time transmission requirements of large amounts of spectral data. Specifically, the timing control based on the APL two-wire integrated power supply and communication system includes the following steps: During the detection phase, the power supply equipment (PSE) periodically sends detection signals on the twisted pair. When the power receiving equipment (PD) is not powered on, the line is in a voltage-free state, and the PSE identifies the PD connection by detecting the circuit impedance. During the grading phase, after detecting a valid PD, the PSE sends a grading signal to determine the PD's power level, and then closes the power supply switch to output a stable 24V APL power supply. After receiving the power, the PD enters the wake-up and initialization state. During the link establishment phase, the physical layer chip inside the PD starts up and continuously sends link pulses to attempt to establish a 10BASE-T1L link with the PSE. Both parties complete full-duplex initialization through automatic negotiation. After successful establishment, they enter the normal communication ready state. During the data communication phase, within each 10ms basic cycle, the PSE provides constant current power to the PD through the same pair of cables. At the same time, in the 1ms burst time slot at the end of the cycle, a full-duplex data signal is superimposed on the power supply line according to the 100BASE-T1L standard to realize the physical layer multiplexing of power supply and communication. During the periodic detection embedding phase, the PSE periodically inserts detection signals to monitor the PD status during data communication. Upon receiving the detection signal, the PD sends back a response pulse to ensure the continuous stability of the link.

[0018] Furthermore, during the data communication phase, when the PD's light source module generates a peak power consumption of 3W at the moment of excitation, the current gap is compensated by the instantaneous discharge of the PD's built-in capacitor energy storage unit, ensuring that the APL bus voltage fluctuation is less than 5%, and the capacitor energy storage unit recovers by current-limited charging at 200mA during the dark state interval when the light source is turned off.

[0019] During the link establishment phase, the PD and PSE use echo cancellation technology to achieve full-duplex communication. Downlink control commands and uplink spectral data are separated in the frequency domain to avoid signal conflicts. At the beginning of each cycle, the communication module sends a 100μs pulse width TTL level synchronization pulse to trigger the light source module to start a new round of wavelength switching.

[0020] The APL industrial communication protocol is shown in the table below: OSI Layering Protocol layer name Core Standards / Protocols Core Functions 7 Application layer FOUNDATION HSE, OPC UA Functional block communication, data acquisition, and equipment maintenance 6 Presentation layer Data encoding / encryption standards Data format conversion, security encryption 5 Session layer FOUNDATION HSE Session Management Establish / terminate communication sessions and coordinate device interactions. 4 transport layer TCP / UDP Reliable transmission (TCP), Real-time transmission (UDP) 3 Network layer IPv4 / IPv6 Routing, cross-segment communication, address allocation 2 Data Link Layer IEEE 802.3 (Ethernet) MAC addressing, real-time scheduling, link redundancy 1 physical layer 100BASE-T1L High-speed, intrinsically safe, bus-powered physical layer transmission In one embodiment, the spectral module is composed of a quantum dot array spectral sensor, which has the advantages of small size, large measurement bandwidth, high wavelength resolution, and good sensitivity in weak light. Its spectral detection range is 350nm~1070nm, and its resolution can reach 2nm.

[0021] In one embodiment, the light source module consists of one or more laser sources of specific wavelengths, which are switched in a time-division manner to excite the generation of fluorescence signals. For example, the light source module includes laser sources with wavelengths of 355 nm, 405 nm, and 532 nm, corresponding to the fluorescence excitation peaks of different substances. In an experiment detecting the concentrations of various substances in a mixed solution of ethyl hexanoate, hexanoic acid, and ethanol, the 355 nm laser source is used to excite the fluorescence properties of ethanol, the 405 nm laser source is used to excite the fluorescence properties of hexanoic acid, and the 532 nm laser source is used to excite the fluorescence properties of ethyl hexanoate.

[0022] Please refer to Figure 4 During fluorescence excitation and signal acquisition, the laser source array adopts a cyclic triggering mode with a complete scan cycle of 500ms, exciting sequentially: 355nm → 405nm → 532nm → 355nm. The pulse width for each wavelength excitation is 100ms to ensure sufficient excitation of the target material and acquisition of a stable fluorescence signal. An interval of ≥20ms is set between adjacent wavelength switching. At the beginning of each excitation cycle, the communication module sends a TTL level synchronization pulse (pulse width 100μs) to the source module to accurately mark the wavelength switching start point. The spectral module starts acquisition 5ms after receiving the synchronization pulse to ensure that the laser power is stable before capturing the fluorescence signal. During each excitation, 10 frames of spectral data are continuously acquired and averaged to obtain the effective spectrum at that wavelength. All spectral data are marked with the offset time relative to the synchronization pulse (accuracy 1μs) to ensure accurate correspondence of each wavelength spectrum during subsequent data fusion.

[0023] The generated fluorescence signal enters the light guide structure through the detection window and is then transmitted to the quantum dot array spectral sensor. The light guide structure, located between the light source module, the spectral module, and the detection window, includes: The light guide column is used to directionally transmit laser and fluorescence signals within a limited space. Its incident end is coupled to the light source module and the spectral module, and its output end is coupled to the detection window. A filter is placed in the optical path of the light guide post. The filter is a dichroic filter, which is used to allow a specific wavelength of laser light to pass through in the excitation optical path and reflect the fluorescence signal, and to allow the fluorescence signal to pass through in the receiving optical path and block laser leakage. The lens group, located at both ends of the light guide post, includes a collimating lens and a focusing lens. The collimating lens is used to collimate the diverging laser beam emitted by the light source module into parallel light, and the focusing lens is used to focus the returned fluorescence signal onto the photosensitive surface of the spectral module.

[0024] The light guide column, together with the filter and lens group, forms a shared channel for the excitation light path and the fluorescence acquisition light path, realizing bidirectional light transmission for light source excitation and signal reception.

[0025] In one embodiment, the detection window is located at the end of the pressure-resistant housing and directly contacts the liquid medium being measured. It employs a modular sealing structure, with the optical window made of quartz glass (JGS1 grade). The inner side integrates a lens and is coated with a broadband anti-reflection film, achieving a transmittance of ≥92% in the 350-1070nm wavelength range. The sealing structure uses rubber O-rings to achieve a window seal, capable of withstanding temperatures from -20℃ to +200℃, pressures of ≥10MPa, and chemical corrosion at pH 2-12. The outer surface of the quartz glass is coated with a hydrophobic and oleophobic nano-coating to prevent contamination. The entire unit is connected to the pressure-resistant housing via threads or flanges, and uses a standard SMA905 / FC fiber optic interface for detachable connection to the internal light guide structure. This design maintains an overall light transmittance efficiency of >85%, enabling long-term stable operation of the miniature probe in high-temperature, high-pressure, and corrosive media, and facilitating rapid on-site maintenance.

[0026] Based on the aforementioned equipment, this application provides an in-situ quantitative analysis method for multi-component substances based on fluorescence spectroscopy. Please refer to [link / reference]. Figure 5 The method includes the following steps: The time-division multi-wavelength excitation step uses a light source module to switch different wavelengths of laser light sources in a preset order to excite the fluorescence properties of each target substance in the mixed liquid. The full-spectrum acquisition step uses a quantum dot array spectral sensor to receive fluorescence signals generated in the time-division multi-wavelength excitation step, generating full-spectrum data covering the range of 350nm~1070nm; The data preprocessing steps involve noise reduction, baseline correction, and normalization of the full-spectrum data to eliminate environmental interference. The component analysis step uses a pre-stored chemometric model to perform real-time analysis on the processed full-spectrum data, and performs nonlinear mapping inversion between spectral intensity and substance concentration to calculate the real-time concentration value of each target component. The data transmission step involves transmitting the calculated concentration data to the external control system in real time via the APL communication module.

[0027] The data preprocessing step is performed in real time by the embedded system after the spectral data is acquired, and specifically includes the following steps: Baseline correction: The background baseline of the fluorescence spectrum was fitted using the adaptive iterative weighted least squares method (airPLS), with 20 iterations. The regularization parameter λ was dynamically adjusted according to the spectral length (λ = 10^4 ~ 10^6) to accurately eliminate baseline drift caused by light scattering, fluorescence quenching, and temperature fluctuations. The baseline-corrected spectrum was then subjected to a first-order derivative transformation with a window width of 5 points to enhance the identification of characteristic peaks and further suppress slowly varying background interference. Noise Reduction: A Savitzky-Golay filter is used for smoothing and noise reduction, with a window width of 7 points and a polynomial order of 3, suppressing high-frequency random noise while preserving the characteristic peak shape. Furthermore, a Discrete Wavelet Transform (DWT) is performed on the smoothed spectrum, using a Daubechies 4th-order wavelet basis with 3 decomposition levels. High-frequency detail coefficients are reset to zero before reconstruction, effectively removing salt-and-pepper noise and electrical impulse interference.

[0028] Normalization: The maximum-minimum normalization method is used to linearly map the spectral intensity values ​​to the [0, 1] interval, eliminating the intensity differences caused by fluctuations in light source power and changes in detection distance.

[0029] The component analysis procedure pre-calibrates using standard samples to establish a partial least squares regression (PLSR) multivariate calibration model. The model parameters are stored in the embedded system's Flash memory, including 3-5 latent variable factors, a regression coefficient matrix, and a spectral loading vector. Upon device power-up, the model is loaded into RAM for high-speed access. For a mixture of ethyl hexanoate, hexanoic acid, and ethanol, the model input is an 18-24 dimensional feature vector (peak heights of 6-8 characteristic wavelength channels for each substance), and the output is a concentration vector for all three components.

[0030] The preprocessed characteristic wavelength intensity vector is centered (by subtracting the mean of the calibration set) and projected into the latent variable space of the PLSR model. The regression equation is then solved quickly using a nonlinear iterative partial least squares (NIPALS) algorithm to achieve a nonlinear mapping from fluorescence intensity to concentration. The calculation results include the concentration values ​​of each component and the standard error of prediction (SEP).

[0031] In summary, the in-situ material composition detection equipment based on fluorescence spectroscopy adopts a highly integrated miniature modular design, mainly composed of four core units: communication module, power supply module, light source module, and spectral module. Combined with a precise light guide structure and detection window, it meets the miniaturized installation requirements of industrial pipelines.

[0032] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. An in-situ material composition detection device based on fluorescence spectroscopy, characterized in that, include: The pressure-resistant housing integrates the following modules, which are interconnected and work together via an APL two-wire bus: The power supply module is used to simultaneously supply power to the light source module and the spectrum module through the APL two-wire bus, and has a built-in capacitor energy storage unit to maintain voltage stability during the peak power consumption of the light source module. The communication module is connected to the APL two-wire bus of the power supply module and is used to realize wavelength switching control of the light source module, full-spectrum data acquisition of the spectral module and full-duplex data transmission through the APL industrial communication protocol. The light source module consists of multiple laser light sources of specific wavelengths. It emits lasers in a time-division manner according to the switching command of the communication module. The lasers are transmitted to the detection window through the light guide structure to excite the liquid medium to generate a fluorescence signal. The spectral module employs a quantum dot array spectral sensor to receive fluorescence signals transmitted through the light guide structure and convert them into full-spectrum data, which is then uploaded in real time via the communication module. The detection window is fixed at the end of the pressure-resistant housing and is directly immersed in the liquid medium in the industrial pipeline or reactor to achieve physical isolation and optical coupling between the optical path and the measured environment.

2. The in-situ material composition detection device based on fluorescence spectroscopy as described in claim 1, characterized in that, The wavelengths of the laser light source include 355nm, 405nm and 532nm, which correspond to the fluorescence excitation peaks of different substances.

3. The in-situ material composition detection device based on fluorescence spectroscopy as described in claim 2, characterized in that, Each laser source operates independently in a time-division manner under the synchronous timing control of the communication module. The 355nm laser source is used to excite the fluorescence properties of ethanol, the 405nm laser source is used to excite the fluorescence properties of hexanoic acid, and the 532nm laser source is used to excite the fluorescence properties of ethyl hexanoate. The fluorescence signals generated by each wavelength are transmitted to the spectral module through the light guide structure.

4. The in-situ material composition detection device based on fluorescence spectroscopy as described in claim 1, characterized in that, The APL two-wire power supply and communication timing control is configured as follows: During the detection phase, the power supply equipment periodically sends detection signals on the twisted pair. When the receiving equipment is not powered on, the line is in a voltage-free state, and the power supply equipment identifies the connection of the receiving equipment by detecting the impedance of the circuit. During the grading phase, after detecting a valid powered device, the power supply equipment sends a grading signal to determine the power level of the powered device, and then closes the power supply switch to output a stable voltage. After receiving the voltage, the powered device enters the wake-up and initialization state. During the link establishment phase, the physical layer chip inside the powered device starts up and continuously sends link pulses to attempt to establish a link with the power supply device. Both parties complete full-duplex initialization through automatic negotiation, and enter the normal communication ready state after successful establishment. During the data communication phase, in each cycle, the power supply equipment provides constant current power to the power receiving equipment through the same pair of cables. At the same time, in the 1ms burst time slot at the end of the cycle, a full-duplex data signal is superimposed on the power supply line to realize the physical layer multiplexing of power supply and communication. During the periodic detection embedding phase, the power supply equipment periodically inserts detection signals to monitor the status of the powered equipment during data communication. Upon receiving the detection signal, the powered equipment sends back a response pulse to ensure the continuous stability of the link.

5. The in-situ material composition detection device based on fluorescence spectroscopy as described in claim 4, characterized in that, During the data communication phase, when the light source module of the powered device generates peak power consumption at the moment of excitation, the built-in capacitor energy storage unit of the powered device instantaneously discharges to compensate for the current gap, ensuring that the APL bus voltage fluctuation is less than the threshold.

6. The in-situ material composition detection device based on fluorescence spectroscopy as described in claim 4, characterized in that, During the link establishment phase, the power receiving device and the power supply device use echo cancellation technology to achieve full-duplex communication. Downlink control commands and uplink spectral data are separated in the frequency domain to avoid signal conflicts. At the beginning of each cycle, the communication module sends a TTL level synchronization pulse to trigger the light source module to start a new round of wavelength switching.

7. The in-situ material composition detection device based on fluorescence spectroscopy as described in claim 1, characterized in that, The light guide structure is disposed between the light source module, the spectral module, and the detection window, and includes: The light guide column is used to directionally transmit laser and fluorescence signals within a limited space. Its incident end is coupled to the light source module and the spectral module, and its output end is coupled to the detection window. A filter is disposed in the optical path of the light guide post. The filter is a dichroic filter, which is used to transmit a laser of a specific wavelength in the excitation optical path and reflect a fluorescence signal, and to transmit a fluorescence signal in the receiving optical path and block laser leakage. A lens assembly, disposed at both ends of the light guide post, includes a collimating lens and a focusing lens. The collimating lens is used to collimate the diverging laser beam emitted by the light source module into parallel light, and the focusing lens is used to focus the returned fluorescence signal onto the photosensitive surface of the spectral module.

8. A method for in-situ quantitative analysis of multi-component substances based on fluorescence spectroscopy, using the equipment as described in any one of claims 1 to 7, characterized in that, Includes the following steps: The time-division multi-wavelength excitation step uses a light source module to switch different wavelengths of laser light sources in a preset order to excite the fluorescence properties of each target substance in the mixed liquid. The full-spectrum acquisition step uses a quantum dot array spectral sensor to receive fluorescence signals generated in the time-division multi-wavelength excitation step, generating full-spectrum data covering the range of 350nm~1070nm; The data preprocessing steps involve noise reduction, baseline correction, and normalization of the full-spectrum data to eliminate environmental interference. The component analysis step uses a pre-stored chemometric model to perform real-time analysis on the processed full-spectrum data, and performs nonlinear mapping inversion between spectral intensity and substance concentration to calculate the real-time concentration value of each target component. The data transmission step involves transmitting the calculated concentration data to the external control system in real time via the APL communication module.

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