An immersion dual-mode optical density detection probe and system

Abstract

This invention relates to the field of photoelectric detection technology and proposes an immersion dual-mode optical density detection probe and system. The probe includes: splitting a single detection beam emitted from a light source into a reference beam and a measurement beam, and illuminating the sample to be tested; performing photoelectric detection conversion on the reference beam, forward transmitted light, and backward reflected light to obtain a reference electrical signal, a transmitted electrical signal, and a reflected electrical signal; performing common-mode component cancellation on the transmitted electrical signal and the reflected electrical signal to obtain a concentration signal pair; based on the concentration distribution identification result of the sample to be tested, performing dual-path fractional nonlinear compensation on the concentration signal pair to obtain transmitted concentration data and reflected concentration data; smoothly splicing and fusing the transmitted concentration data and reflected concentration data to obtain transition region concentration data; and performing reliability optimization on the transmitted concentration data, reflected concentration data, and transition region concentration data to confirm the optical density of the sample to be tested. This invention can improve the efficiency of immersion dual-mode optical density detection.

Description

Technical Field

[0001] This invention relates to the field of photoelectric detection technology, and in particular to an immersion dual-mode optical density detection probe and system. Background Technology

[0002] Existing immersion optical density detection methods have relatively simple optical path designs and lack diverse detection modes. They cannot adaptively adjust according to the concentration distribution of the sample to be tested. During the detection process, they are easily affected by various common-mode interference factors, which causes deviations in the electrical signal after photoelectric conversion, making it difficult to accurately reflect the actual concentration characteristics of the sample to be tested.

[0003] Existing technologies lack a sound concentration zoning identification and compensation mechanism, as well as methods for fusion and reliability assessment of data from different concentration ranges. This results in poor connectivity of detection data across different concentration ranges, insufficient accuracy and stability of overall detection results, and significant limitations in the applicable concentration range. Therefore, improving the accuracy, stability, and applicability of immersion optical density detection has become an urgent problem to be solved. Summary of the Invention

[0004] This invention provides an immersion dual-mode optical density detection probe and system to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides an immersion dual-mode optical density detection probe, comprising: S1. The single beam of detection light emitted by the light source is split into a reference beam and a measurement beam, and the measurement beam is coupled and incident on the immersion fiber optic probe to illuminate the sample to be tested; S2. Perform photoelectric detection conversion on the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source. S3. Using the reference electrical signal as the fluctuation correction benchmark, common-mode component cancellation is performed on the transmitted electrical signal and the reflected electrical signal to obtain the concentration signal pair of the sample to be tested; S4. Based on the concentration signal pair, the concentration distribution of the sample to be tested is identified, and based on the identification result, dual-path nonlinear compensation is performed on the concentration signal pair to obtain the transmission concentration data and reflection concentration data of the sample to be tested. S5. The transmission concentration data and the reflection concentration data are smoothly spliced ​​and fused to obtain the transition region concentration data of the sample to be tested; S6. Optimize the reliability of the transmission concentration data, the reflection concentration data, and the transition region concentration data to confirm the optical density of the sample to be tested.

[0006] In a preferred embodiment, the step of splitting the single-beam detection light emitted from the light source into a reference beam and a measurement beam, and coupling the measurement beam to an immersion fiber optic probe to illuminate the sample to be tested, includes: According to a preset fixed ratio, the single beam of detection light emitted by the light source is optically decoupled to obtain the reference beam and the measurement beam of the light source. The beam diameter of the measurement beam is adjusted to obtain a focused transmission beam. The sample to be tested is illuminated by the focused transmission beam.

[0007] In a preferred embodiment, the photoelectric detection conversion of the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source includes: Based on the same time reference, parallel photoelectric sampling is performed on the reference beam, forward transmitted light and backscattered light of the light source to obtain the original reference analog quantity, original transmission analog quantity and original reflection analog quantity of the light source; Gain adaptation adjustment is performed on the original reference analog quantity, the original transmission analog quantity, and the original reflection analog quantity to obtain the adjusted reference analog quantity, the adjusted transmission analog quantity, and the adjusted reflection analog quantity of the light source. The adjusted reference analog quantity, the adjusted transmission analog quantity, and the adjusted reflection analog quantity are converted from analog to digital to obtain the reference electrical signal, transmission electrical signal, and reflection electrical signal of the light source.

[0008] In a preferred embodiment, the step of using the reference electrical signal as a fluctuation correction benchmark to perform common-mode component cancellation on the transmitted electrical signal and the reflected electrical signal to obtain the concentration signal pair of the sample to be tested includes: Extract the instantaneous amplitude of the reference electrical signal in a continuous time series to construct a reference fluctuation feature sequence of the reference electrical signal; Based on the reference fluctuation characteristic sequence, common-mode suppression calibration is performed on the transmitted electrical signal and the reflected electrical signal to obtain the transmission channel correction and reflection channel correction of the transmitted electrical signal and the reflected electrical signal; Based on the time-domain characteristics of the reference electrical signal, the transmission channel correction and the reflection channel correction are correlated and configured to obtain the concentration signal pair of the sample to be tested.

[0009] In a preferred embodiment, the step of identifying the concentration distribution of the sample to be tested based on the concentration signal pair includes: Component focusing evaluation is performed on the concentration signal pair to obtain the transmission signal intensity of the concentration signal pair; The intensity of the transmitted signal is compared with a preset effective transmission threshold and a preset effective reflection threshold within a certain range. When the intensity of the transmitted signal is higher than the effective transmission threshold, the concentration distribution of the sample to be tested is identified as the transmission-dominant region. When the intensity of the transmitted signal is lower than the effective reflection threshold, the concentration distribution of the sample to be tested is identified as the reflection-dominant region. When the intensity of the transmitted signal is between the effective reflection threshold and the effective transmission threshold, the concentration distribution state of the sample to be tested is identified as a smooth transition region.

[0010] In a preferred embodiment, the step of performing dual-path fractional nonlinear compensation on the concentration signal pair based on the identification result to obtain the transmission concentration data and reflectance concentration data of the sample to be tested includes: Obtain the corrected transmission signal and corrected reflection signal corresponding to the irradiation of a standard sample of known concentration; The corrected transmission signal and the corrected reflection signal are nonlinearly fitted with the known concentration value of the known concentration standard sample to obtain a first fractional mapping relationship and a second fractional mapping relationship between the corrected transmission signal and the corrected reflection signal and the known concentration value; When the concentration distribution state is identified as a transmission-dominant region, the transmission concentration data of the sample to be tested is calculated based on the first fractional mapping relationship. When the concentration distribution state is identified as a reflection-dominant region, based on the second fractional mapping relationship, the fitting parameters of the corrected reflection signal in the concentration signal pair are derived to obtain the reflection concentration data of the sample to be tested. When the concentration distribution state is identified as a smooth transition region, based on the first fractional mapping relationship and the second fractional mapping relationship, dual-path parametric analysis is performed on the corrected transmission signal and corrected reflection signal in the concentration signal pair to obtain the transition region transmission concentration data and transition region reflection concentration data of the sample to be tested. The transmission concentration data and the reflection concentration data of the transition region are used as the transmission concentration data and reflection concentration data of the sample to be tested.

[0011] In a preferred embodiment, the formula for calculating the reflectance concentration data is as follows: ; In the formula, The transmission concentration data of the sample to be tested. The amplitude of the corrected transmission signal. Let be the coefficient of the quadratic term in the first fractional mapping relationship. Let be the coefficient of the first-order term in the first fractional mapping relationship. This is the numerator constant term of the first fractional mapping relationship. Let be the coefficient of the linear term in the denominator of the first fractional mapping relationship. The constant term in the denominator of the first fractional mapping relationship is... This is the global offset of the first fractional mapping relationship.

[0012] In a preferred embodiment, the step of smoothly stitching and fusing the transmission concentration data and the reflection concentration data to obtain the transition region concentration data of the sample to be tested includes: Using the effective reflection threshold and the effective transmission threshold as interval benchmarks, the relative position weight analysis is performed on the transmission signal intensity to obtain the transmission fusion coefficient and the reflection fusion coefficient of the transmission signal intensity; Based on the transmission fusion coefficient and the reflection fusion coefficient, the transmission concentration data and the reflection concentration data are factor-weighted and synthesized to obtain the first fusion component and the second fusion component of the transmission concentration data and the reflection concentration data; The first fusion component and the second fusion component are accumulated and merged to obtain the transition region concentration data of the sample to be tested.

[0013] In a preferred embodiment, the step of performing confidence optimization on the transmission concentration data, the reflection concentration data, and the transition region concentration data to confirm the optical density of the sample to be tested includes: Fluctuation deviation analysis was performed on the transmission concentration data to obtain the time-series stability coefficient of the transmission concentration data; The original reflected electrical signal corresponding to the reflected concentration data is evaluated by signal-to-noise separation to obtain the signal-to-noise margin coefficient of the reflected concentration data. The weighting ratio of the transmission fusion coefficient and the reflection fusion coefficient is determined to obtain the fusion balance coefficient of the transition region concentration data; The optical density of the sample under test is confirmed based on the time stability coefficient, the signal-to-noise margin coefficient, and the fusion balance coefficient.

[0014] To address the above problems, the present invention also provides an immersion dual-mode optical density detection system, the system comprising: The dual-optical-path construction module is used to split the single-beam detection light emitted by the light source into a reference beam and a measurement beam, and couple the measurement beam into the immersion fiber optic probe to illuminate the sample to be tested; The photoelectric conversion acquisition module is used to perform photoelectric detection and conversion on the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test, to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source. The common-mode cancellation correction module is used to cancel the common-mode components of the transmitted electrical signal and the reflected electrical signal using the reference electrical signal as the fluctuation correction reference, so as to obtain the concentration signal pair of the sample to be tested; The partition compensation mapping module is used to identify the concentration distribution of the sample to be tested based on the concentration signal pair, and to perform dual-path fractional nonlinear compensation on the concentration signal pair based on the identification result, so as to obtain the transmission concentration data and reflection concentration data of the sample to be tested. The transition region fusion module is used to smoothly stitch and fuse the transmission concentration data and the reflection concentration data to obtain the transition region concentration data of the sample to be tested. The confidence optimization output module is used to perform confidence optimization on the transmission concentration data, the reflection concentration data and the transition region concentration data to confirm the optical density of the sample to be tested.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention adopts a dual-mode detection architecture combined with reference beam calibration. By canceling common-mode components, it effectively eliminates signal errors caused by interference such as light source fluctuations, thereby improving the accuracy of the detection signal. At the same time, it achieves accurate division of different concentration regions of the sample through concentration distribution identification. Dual-path split nonlinear compensation makes the concentration data calculation of each concentration region more consistent with the actual sample, which greatly improves the accuracy of the concentration data.

[0016] 2. This invention achieves seamless acquisition of concentration data in the transition zone through smooth splicing and fusion, solving the problem of data gaps between different concentration zones. Furthermore, the data is screened through a multi-dimensional reliability selection mechanism, further ensuring the reliability of the optical density detection results. The modular design of the overall detection process also improves the overall efficiency of immersion optical density detection and broadens the applicable concentration range of the detection technology. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of an immersion dual-mode optical density detection probe provided in an embodiment of the present invention; Figure 2 This is a functional block diagram of an immersion dual-mode optical density detection system provided in an embodiment of the present invention; The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] This application provides an immersion dual-mode optical density detection probe. The execution entity of the immersion dual-mode optical density detection probe includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the probe provided in this application embodiment: a server, a terminal, etc. In other words, the immersion dual-mode optical density detection probe can be executed by software or hardware installed on a terminal device or a server device. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster. The server can be an independent server or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDN), and big data and artificial intelligence platforms.

[0020] Reference Figure 1 The diagram shown is a flowchart illustrating an immersion dual-mode optical density detection probe according to an embodiment of the present invention. In this embodiment, the immersion dual-mode optical density detection probe includes: S1. The single beam of detection light emitted by the light source is split into a reference beam and a measurement beam, and the measurement beam is coupled and incident on the immersion fiber optic probe to illuminate the sample to be tested; In this embodiment of the invention, the step of splitting the single-beam detection light emitted from the light source into a reference beam and a measurement beam, and coupling the measurement beam to be incident on an immersion fiber optic probe to illuminate the sample to be tested, includes: According to a preset fixed ratio, the single beam of detection light emitted by the light source is optically decoupled to obtain the reference beam and the measurement beam of the light source. The beam diameter of the measurement beam is adjusted to obtain a focused transmission beam. The sample to be tested is illuminated by the focused transmission beam.

[0021] The single beam of detection light emitted by the light source is sent into the fiber optic coupler. Inside the fiber optic coupler, the single beam of detection light is decoupled into two independently transmitted beams according to a pre-calibrated fixed optical energy distribution ratio. One beam is used as a reference beam, and the other beam is used as a measurement beam. The reference beam enters the subsequent photoelectric detection stage without passing through any sample under test, while the measurement beam enters the subsequent optical path adjustment stage.

[0022] The measurement beam obtained after beam splitting is adjusted to converge the beam diameter. The measurement beam is passed sequentially through a converging lens group consisting of a plano-convex lens and a biconvex lens. The flat end of the plano-convex lens faces the incident direction of the measurement beam, and the central axis of the biconvex lens is aligned with the transmission axis of the measurement beam. When the measurement beam passes through the plano-convex lens, the diameter of its transmission cross section begins to gradually shrink. After passing through the plano-convex lens and then the biconvex lens, its beam diameter shrinks further, forming a focused transmission beam with a diameter significantly smaller than the original beam diameter.

[0023] The exit face of the focused transmission beam is coaxially aligned with the incident face of the immersion fiber optic probe. The focused transmission beam is coupled into the probe through the window glass of the incident face of the immersion fiber optic probe. Inside the probe, a collimating lens and a focusing lens are arranged sequentially along the optical path. The focused transmission beam is first converted into a parallel beam by the collimating lens, and then converged by the focusing lens to illuminate the exit window of the detection end of the immersion fiber optic probe. The beam emitted vertically from the exit window forms a circular detection spot on the surface of the detection area of ​​the sample to be tested.

[0024] The detection end of the immersion fiber optic probe is fully immersed in the pre-defined detection area of ​​the sample to be tested, and the detection spot is perpendicular to the medium surface of the sample to be tested. The focused transmission beam illuminates the entire detection area of ​​the sample to be tested in a vertical direction, ensuring that the beam and the sample to be tested are in full contact. Part of the photons in the beam pass through the sample to be tested to form forward transmitted light, and the other part of the photons are reflected at the internal particles or interfaces of the sample to form backward reflected light. The backward reflected light returns along the original optical path to the reflected light collection fiber inside the probe.

[0025] The reference beam, forward transmitted light, and backward reflected light are acquired simultaneously, and the three optical signals are sent to three independent photodetectors. Each photodetector is connected to the same clock source to ensure that the three detectors work in parallel under the same time reference. The reference beam directly illuminates the reference detector to generate a reference electrical signal, the forward transmitted light illuminates the transmission detector to generate a transmission electrical signal, and the backward reflected light illuminates the reflection detector to generate a reflection electrical signal.

[0026] The reference electrical signal, transmitted electrical signal, and reflected electrical signal are respectively sent to their respective signal conditioning circuits. Each signal conditioning circuit contains a preamplifier and a gain regulator. The preamplifier amplifies the weak electrical signal to a processable range, and the gain regulator automatically selects an appropriate amplification factor based on the amplitude of the current signal, so that the amplitude of all electrical signals is uniformly adjusted to the same standard voltage range, thus obtaining the conditioned reference electrical signal, transmitted electrical signal, and reflected electrical signal.

[0027] Using a reference electrical signal as the fluctuation correction benchmark, common-mode component cancellation is performed on the transmitted and reflected electrical signals. Specifically, the instantaneous amplitudes of the reference, transmitted, and reflected electrical signals are read at the same time point. Since the reference beam does not pass through the sample under test, its amplitude fluctuation is entirely due to the intensity change of the light source itself. Therefore, the instantaneous amplitude of the transmitted signal is subtracted from the instantaneous amplitude of the reference signal to obtain the transmission correction amplitude after eliminating the light source fluctuation. Similarly, the instantaneous amplitude of the reflected signal is subtracted from the instantaneous amplitude of the reference signal to obtain the reflection correction amplitude after eliminating the light source fluctuation. The transmission correction amplitude and reflection correction amplitude at all time points are arranged in chronological order to form the concentration signal pair of the sample under test.

[0028] Concentration distribution identification is performed on the concentration signal pairs. Specifically, the average amplitude of the transmission correction amplitude in the concentration signal pair over a continuous time series is calculated. This average amplitude is compared with two pre-set thresholds, namely the effective transmission threshold and the effective reflection threshold. The effective transmission threshold is greater than the effective reflection threshold. When the average amplitude is higher than the effective transmission threshold, the sample is determined to be in the transmission-dominant region. When the average amplitude is lower than the effective reflection threshold, the sample is determined to be in the reflection-dominant region. When the average amplitude is between the effective reflection threshold and the effective transmission threshold, the sample is determined to be in the smooth transition region.

[0029] Based on the concentration distribution identification results, dual-path fractional nonlinear compensation is performed on the concentration signal pairs. First, a set of standard samples with known concentrations are acquired. Following the same optical path and signal processing procedure as the sample to be tested, the amplitude of the corrected transmission signal and the amplitude of the corrected reflection signal for each standard sample are measured. The amplitude of the corrected transmission signal is mapped to the known concentration value of the standard sample. A mapping relationship between the amplitude of the corrected transmission signal and the concentration value is established through nonlinear fitting. Similarly, a mapping relationship between the amplitude of the corrected reflection signal and the concentration value is established. When the sample to be tested is in the transmission-dominant region, the transmission correction amplitude of the sample to be tested is substituted into the transmission mapping relationship to obtain the transmission concentration data. When the sample to be tested is in the reflection-dominant region, the reflection correction amplitude of the sample to be tested is substituted into the reflection mapping relationship to obtain the reflection concentration data. When the sample to be tested is in the smooth transition region, the transmission correction amplitude and the reflection correction amplitude are substituted into the two mapping relationships respectively to obtain the transmission concentration data and reflection concentration data of the transition region.

[0030] The transmission concentration data and reflection concentration data are smoothly stitched and fused. The specific operation is as follows: the average amplitude of the sample under test when it is judged in the smooth transition zone is obtained, the relative position of the average amplitude in the interval formed by the effective reflection threshold and the effective transmission threshold is calculated, a transmission fusion coefficient and a reflection fusion coefficient are determined according to the relative position, the sum of the transmission fusion coefficient and the reflection fusion coefficient is a fixed value, the transmission concentration data is multiplied by the transmission fusion coefficient to obtain a product, the reflection concentration data is multiplied by the reflection fusion coefficient to obtain another product, and the two products are added together to obtain the transition zone concentration data.

[0031] The reliability of transmission concentration data, reflection concentration data, and transition zone concentration data is optimized by the following steps: The reliability metric for each of the three data points is calculated. The reliability metric for transmission concentration data is determined based on its fluctuation amplitude over a continuous time series. The reliability metric for reflection concentration data is determined based on the ratio of effective signal to noise in its corresponding original reflected electrical signal. The reliability metric for transition zone concentration data is determined based on the difference between the transmission fusion coefficient and the reflection fusion coefficient. Each of the three reliability metrics is compared with a preset judgment threshold. The data point with the highest reliability metric that is not lower than the judgment threshold is selected as the final optical density output result of the sample under test.

[0032] The beneficial effects are as follows: By obtaining a reference beam of the same origin as the measurement beam through fixed-ratio optical path decoupling, a precise fluctuation reference is provided for subsequent signal correction; the common-mode component cancellation operation directly eliminates common-mode interference caused by light source intensity fluctuations, significantly improving the signal-to-noise ratio of transmitted and reflected signals; through beam diameter convergence adjustment and the cooperation of the lens group inside the probe, efficient coupling and vertical emission of the focused transmission beam are achieved, avoiding energy loss and logical contradictions in the optical path design, and ensuring full contact between the detection light and the sample under test; through concentration distribution identification, dual-path fractional nonlinear compensation, smooth splicing and fusion, and confidence-optimized stepwise processing, the system can adapt to the detection requirements of different concentration ranges. The data in the transmission-dominant region and the reflection-dominant region each adopt the optimal mapping relationship, and the smooth transition region achieves seamless connection of the two data through the fusion coefficient. Finally, the most reliable data is selected as the output through multi-dimensional confidence evaluation, thereby ensuring the accuracy, stability, and continuity of optical density detection results throughout the entire concentration range.

[0033] S2. Perform photoelectric detection conversion on the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source. In this embodiment of the invention, the photoelectric detection conversion of the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source includes: Based on the same time reference, parallel photoelectric sampling is performed on the reference beam, forward transmitted light and backscattered light of the light source to obtain the original reference analog quantity, original transmission analog quantity and original reflection analog quantity of the light source; Gain adaptation adjustment is performed on the original reference analog quantity, the original transmission analog quantity, and the original reflection analog quantity to obtain the adjusted reference analog quantity, the adjusted transmission analog quantity, and the adjusted reflection analog quantity of the light source. The adjusted reference analog quantity, the adjusted transmission analog quantity, and the adjusted reflection analog quantity are converted from analog to digital to obtain the reference electrical signal, transmission electrical signal, and reflection electrical signal of the light source.

[0034] Based on the same time reference, parallel photoelectric sampling is performed on the reference beam of the light source, the forward transmitted light after passing through the sample under test, and the backscattered light reflected by the sample under test. The three beams are respectively irradiated onto three independently packaged photodetectors. The sampling trigger terminal of each photodetector is electrically connected to the output terminal of the same quartz crystal oscillator clock source. After the clock source is powered on, it generates a continuous and stable square wave clock signal. The three photodetectors synchronously start photoelectric conversion at each rising edge of the clock signal, converting the received light energy into the corresponding voltage amplitude, and obtaining the original reference analog quantity, the original transmission analog quantity, and the original reflection analog quantity of the light source.

[0035] Gain adaptation adjustment is performed on the original reference analog quantity, original transmission analog quantity, and original reflection analog quantity. Each original analog quantity is sent to its corresponding programmable gain amplifier. The programmable gain amplifier consists of a multi-stage operational amplifier and an analog switch. First, the instantaneous peak voltage of the input original analog quantity is read through the built-in amplitude detection circuit. This peak voltage is compared with three amplitude ranges pre-stored in the amplifier register. The first range is the low amplitude range, the second range is the medium amplitude range, and the third range is the high amplitude range. When the peak voltage falls in the low amplitude range, the analog switch connects the high gain amplification path. When the peak voltage falls in the medium amplitude range, the analog switch connects the unity gain amplification path. When the peak voltage falls in the high amplitude range, the analog switch connects the low gain amplification path. After gain adjustment, the amplitude of the analog voltage is compressed to the same standard voltage output range, resulting in the adjusted reference analog quantity, adjusted transmission analog quantity, and adjusted reflection analog quantity of the light source.

[0036] The regulated reference analog signal, regulated transmitted analog signal, and regulated reflected analog signal are converted from analog to digital. Each regulated analog signal is sent to its corresponding successive approximation analog-to-digital converter (ADC). The conversion start pin of each ADC is electrically connected to the output of the same quartz crystal oscillator clock source to ensure that the three ADCs start conversion synchronously at the falling edge of the same clock signal. The ADC contains a sample-and-hold circuit, a comparator, a successive approximation register, and a digital-to-analog converter (DAC). The sample-and-hold circuit first captures and keeps the voltage value of the regulated analog signal constant. The successive approximation register sets the value bit by bit starting from the most significant bit. The DAC converts the value in the register into the corresponding analog voltage. The comparator compares the analog voltage with the voltage in the sample-and-hold circuit and determines the final value of each bit based on the comparison result. After all bits are determined, the value in the register is the converted digital signal. This digital signal is read in parallel from the data output of the ADC to obtain the reference electrical signal, transmitted electrical signal, and reflected electrical signal of the light source. These three electrical signals are discrete digital signal sequences.

[0037] The beneficial effects are as follows: By driving three photodetectors to sample in parallel using the same clock source, the time deviation between the three signals is eliminated, enabling subsequent signal processing to be carried out on a completely synchronized time axis; by automatically selecting the appropriate gain level based on the actual amplitude of the original analog quantity using a programmable gain amplifier, light signals of different intensities are unified into the same voltage range, avoiding the problems of signals that are too small to be recognized or too large to cause saturation distortion; by accurately converting the adjusted analog quantity into a digital signal using a successive approximation analog-to-digital converter, and by using the same clock source to trigger the three converters synchronously, the timing consistency and comparability of the conversion results are guaranteed, providing a high-quality, synchronously aligned digital signal foundation for subsequent elimination of light source fluctuations based on reference electrical signals.

[0038] S3. Using the reference electrical signal as the fluctuation correction benchmark, common-mode component cancellation is performed on the transmitted electrical signal and the reflected electrical signal to obtain the concentration signal pair of the sample to be tested; In this embodiment of the invention, the step of using the reference electrical signal as a fluctuation correction benchmark to perform common-mode component cancellation on the transmitted electrical signal and the reflected electrical signal to obtain the concentration signal pair of the sample to be tested includes: Extract the instantaneous amplitude of the reference electrical signal in a continuous time series to construct a reference fluctuation feature sequence of the reference electrical signal; Based on the reference fluctuation characteristic sequence, common-mode suppression calibration is performed on the transmitted electrical signal and the reflected electrical signal to obtain the transmission channel correction and reflection channel correction of the transmitted electrical signal and the reflected electrical signal; Based on the time-domain characteristics of the reference electrical signal, the transmission channel correction and the reflection channel correction are correlated and configured to obtain the concentration signal pair of the sample to be tested.

[0039] The instantaneous amplitude of the reference electrical signal in a continuous time series is extracted to construct a reference fluctuation characteristic sequence of the reference electrical signal. The reference electrical signal is treated as a one-dimensional digital sequence that changes with time. The amplitude data at each time point is read one by one from the sequence according to the chronological order of the sampling time points. These amplitude data are arranged in chronological order to form a new sequence that corresponds one-to-one with the original sampling time. This new sequence completely records the real-time fluctuation of the light intensity of the light source during the entire detection period. This new sequence is defined as the reference fluctuation characteristic sequence.

[0040] Based on the reference fluctuation characteristic sequence, common-mode suppression calibration is performed on the transmitted and reflected electrical signals to obtain the transmission channel correction and reflection channel correction values. The transmitted electrical signal sequence and the reference fluctuation characteristic sequence are aligned point by point on the same time axis. At each aligned time point, the amplitude of the corresponding time point in the reference fluctuation characteristic sequence is subtracted from the amplitude of the transmitted electrical signal to obtain the difference at that time point. All the differences at all time points are arranged in chronological order to form a new sequence, which is the transmission channel correction value. Similarly, the reflected electrical signal sequence and the reference fluctuation characteristic sequence are aligned point by point on the same time axis. At each aligned time point, the amplitude of the corresponding time point in the reference fluctuation characteristic sequence is subtracted from the amplitude of the reflected electrical signal to obtain the difference at that time point. All the differences at all time points are arranged in chronological order to form a new sequence, which is the reflection channel correction value. After the above point-by-point subtraction operation, the common-mode components generated by the intensity fluctuation of the light source itself in the transmitted and reflected electrical signals are completely eliminated.

[0041] Based on the time-domain characteristics of the reference electrical signal, the transmission channel correction and reflection channel correction are correlated and combined to obtain the concentration signal pairs of the sample under test. The time-domain characteristics of the reference electrical signal are represented by a discrete sequence of sampling points at equal time intervals, with each sampling point corresponding to a unique time marker. According to this time-domain characteristic, a pair of correction values ​​with the same time marker is extracted from the transmission channel correction sequence and the reflection channel correction sequence. These two values ​​are combined into a binary tuple. The first element of the binary tuple is the value of the transmission channel correction at that time, and the second element is the value of the reflection channel correction at that time. The above combination operation is repeated for each sampling time to obtain a series of binary tuples arranged in chronological order. All these binary tuples together constitute the concentration signal pairs of the sample under test. Each pair of data in the concentration signal pairs simultaneously contains the transmission information and reflection information after correction for light source fluctuations.

[0042] The beneficial effects are as follows: By extracting the instantaneous amplitude of the reference electrical signal to construct a reference fluctuation feature sequence, the real-time fluctuation trajectory of the light intensity of the light source is completely recorded, providing reference data that is completely synchronized with the transmitted and reflected signals for subsequent calibration; by performing common-mode suppression calibration on the transmitted and reflected electrical signals by subtracting the amplitude point by point based on the reference fluctuation feature sequence, the common-mode interference introduced by the intensity fluctuation of the light source itself is accurately eliminated, so that the correction values ​​of the transmission channel and the reflection channel truly reflect the absorption and scattering of light by the sample under test, eliminating the measurement error caused by the instability of the light source; by associating the correction values ​​of the transmission channel and the reflection channel with the same time identifier to construct a concentration signal pair, the strict alignment of the data of the two channels in the time dimension is ensured, so that each pair of data in the concentration signal pair has the same sampling time and a consistent light source fluctuation correction background, providing a reliable signal basis for subsequent concentration distribution identification with time matching and clean interference removal.

[0043] S4. Based on the concentration signal pair, the concentration distribution of the sample to be tested is identified, and based on the identification result, dual-path nonlinear compensation is performed on the concentration signal pair to obtain the transmission concentration data and reflection concentration data of the sample to be tested. In this embodiment of the invention, the step of identifying the concentration distribution of the sample to be tested based on the concentration signal pair includes: Component focusing evaluation is performed on the concentration signal pair to obtain the transmission signal intensity of the concentration signal pair; The intensity of the transmitted signal is compared with a preset effective transmission threshold and a preset effective reflection threshold within a certain range. When the intensity of the transmitted signal is higher than the effective transmission threshold, the concentration distribution of the sample to be tested is identified as the transmission-dominant region. When the intensity of the transmitted signal is lower than the effective reflection threshold, the concentration distribution of the sample to be tested is identified as the reflection-dominant region. When the intensity of the transmitted signal is between the effective reflection threshold and the effective transmission threshold, the concentration distribution state of the sample to be tested is identified as a smooth transition region.

[0044] Based on the identification results, dual-path fractional nonlinear compensation is performed on the concentration signal pair to obtain the transmission concentration data and reflectance concentration data of the sample under test, including: Obtain the corrected transmission signal and corrected reflection signal corresponding to the irradiation of a standard sample of known concentration; The corrected transmission signal and the corrected reflection signal are nonlinearly fitted with the known concentration value of the known concentration standard sample to obtain a first fractional mapping relationship and a second fractional mapping relationship between the corrected transmission signal and the corrected reflection signal and the known concentration value; When the concentration distribution state is identified as a transmission-dominant region, the transmission concentration data of the sample to be tested is calculated based on the first fractional mapping relationship. When the concentration distribution state is identified as a reflection-dominant region, based on the second fractional mapping relationship, the fitting parameters of the corrected reflection signal in the concentration signal pair are derived to obtain the reflection concentration data of the sample to be tested. When the concentration distribution state is identified as a smooth transition region, based on the first fractional mapping relationship and the second fractional mapping relationship, dual-path parametric analysis is performed on the corrected transmission signal and corrected reflection signal in the concentration signal pair to obtain the transition region transmission concentration data and transition region reflection concentration data of the sample to be tested. The transmission concentration data and the reflection concentration data of the transition region are used as the transmission concentration data and reflection concentration data of the sample to be tested. The formula for calculating the reflectance concentration data is as follows: ; In the formula, The transmission concentration data of the sample to be tested. The amplitude of the corrected transmission signal. Let be the coefficient of the quadratic term in the first fractional mapping relationship. Let be the coefficient of the first-order term in the first fractional mapping relationship. This is the numerator constant term of the first fractional mapping relationship. Let be the coefficient of the linear term in the denominator of the first fractional mapping relationship. The constant term in the denominator of the first fractional mapping relationship is... This is the global offset of the first fractional mapping relationship.

[0045] The first element of each binary pair in the concentration signal pair, i.e., the value of the transmission channel correction, is extracted one by one. All these values ​​are summed to obtain a total value. Then, the total number of binary pairs contained in the concentration signal pair is counted. The transmission signal intensity is obtained by dividing the total value by the total number. This transmission signal intensity represents the average amplitude level of the transmission channel correction within the current detection cycle.

[0046] The transmitted signal intensity is compared with the preset effective transmission threshold and the preset effective reflection threshold. The effective transmission threshold and the effective reflection threshold are two fixed values ​​predetermined during the probe's factory calibration stage. The calibration method is as follows: take a pure solvent that does not contain the analyte as a blank sample, immerse the probe in the blank sample to obtain the baseline value of the transmitted signal intensity, multiply the baseline value by a fixed coefficient less than one to obtain the effective transmission threshold, and then take a saturated solution of the analyte with a very high concentration as a high-concentration sample, immerse the probe in the high-concentration sample to obtain the lower limit value of the transmitted signal intensity, and multiply the lower limit value by a fixed coefficient greater than one to obtain the effective reflection threshold. The effective transmission threshold is numerically higher than the effective reflection threshold.

[0047] When the intensity of the transmitted signal is higher than the effective threshold of transmission, the concentration distribution of the sample to be tested is identified as the transmission-dominant region. This state indicates that the concentration of the sample to be tested is low, the attenuation of the measuring beam is very small when it passes through the sample, and the intensity of the transmitted signal is sufficient and stable. At this time, the transmission detection result is the main basis.

[0048] When the intensity of the transmitted signal is lower than the effective threshold of reflection, the concentration distribution of the sample to be tested is identified as the reflection-dominant region. This state indicates that the concentration of the sample to be tested is high, and the measuring beam is absorbed and scattered in large quantities when passing through the sample. The transmitted signal is extremely weak and cannot be used reliably, but the intensity of the back reflection signal is relatively sufficient. At this time, the reflection detection result is the main basis.

[0049] When the intensity of the transmitted signal is between the effective threshold of reflection and the effective threshold of transmission, the concentration distribution of the sample to be tested is identified as a smooth transition region. This state indicates that the concentration of the sample to be tested is in a medium range. Both the transmitted and reflected signals have a certain intensity, but there will be errors if either one is used alone. At this time, it is necessary to use both together.

[0050] To obtain the calibrated transmission and calibrated reflection signals corresponding to the irradiation of standard samples with known concentrations, during the probe's factory calibration stage, a set of standard samples with gradient concentrations are prepared. The concentration value of each standard sample has been determined by a high-precision reference method. The probe is immersed into each standard sample in sequence, and the light source beam splitting, beam irradiation, photoelectric detection conversion, and common-mode component cancellation operations are performed in the same manner as for the sample to be tested. The average value of the transmission channel correction and the average value of the reflection channel correction for each standard sample are recorded from the output of the common-mode component cancellation. The average value of the transmission channel correction is named the calibrated transmission signal of the standard sample, and the average value of the reflection channel correction is named the calibrated reflection signal of the standard sample. Each standard sample corresponds to a unique set of calibrated transmission and calibrated reflection signals.

[0051] Nonlinear fitting is performed on the corrected transmission signal and corrected reflection signal with the known concentration value of the standard sample to obtain the first fractional mapping relationship and the second fractional mapping relationship between the corrected transmission signal and corrected reflection signal and the known concentration value. The corrected transmission signal values ​​of all standard samples and their known concentration values ​​are plotted as a series of discrete points on the coordinate plane. A continuous curve is drawn through these discrete points such that each point falls on or is close to the curve. The correspondence described by this curve is the first fractional mapping relationship. Similarly, the corrected reflection signal values ​​of all standard samples and their known concentration values ​​are plotted as another continuous curve. The correspondence described by this curve is the second fractional mapping relationship. Both curves are stored in a read-only memory for subsequent detection.

[0052] When the concentration distribution is identified as a transmission-dominant region, the transmission concentration data of the sample to be tested is calculated based on the first fractional mapping relationship. The average value of the transmission channel correction obtained by the sample to be tested in the current detection cycle is used as the query value. The concentration value corresponding to the query value is found in the first fractional mapping relationship curve. The found concentration value is the transmission concentration data of the sample to be tested.

[0053] When the concentration distribution is identified as a reflection-dominant region, the corrected reflection signal in the concentration signal pair is fitted with parameters based on the second fractional mapping relationship to obtain the reflection concentration data of the sample to be tested. The average value of the reflection channel correction obtained by the sample to be tested in the current detection cycle is used as the query value. The concentration value corresponding to the query value is found in the second fractional mapping relationship curve. The found concentration value is the reflection concentration data of the sample to be tested.

[0054] When the concentration distribution is identified as a smooth transition region, based on the first and second fractional mapping relationships, dual-path parametric analysis is performed on the corrected transmission signal and corrected reflection signal in the concentration signal pair to obtain the transmission concentration data and reflection concentration data of the sample under test in the transition region. The average value of the transmission channel correction of the sample under test is used to find the corresponding concentration value in the first fractional mapping relationship curve to obtain the transmission concentration data of the transition region. At the same time, the average value of the reflection channel correction of the sample under test is used to find the corresponding concentration value in the second fractional mapping relationship curve to obtain the reflection concentration data of the transition region.

[0055] Transmission concentration data and reflection concentration data in the transition region are used as transmission concentration data and reflection concentration data of the sample to be tested. That is, when the sample to be tested is in the smooth transition region, the concentration data obtained from the two separate analyses are retained for subsequent fusion.

[0056] The amplitude of the corrected transmission signal refers to the value of the transmission channel correction obtained from the detection process of standard samples of known concentration. This value is measured by immersing the probe in a pre-prepared standard sample of known concentration during the probe's factory calibration stage. Each standard sample corresponds to a unique corrected transmission signal amplitude.

[0057] The quadratic coefficient is a constant used to describe the weight of the square term of the corrected transmission signal amplitude in the entire fractional mapping relationship. This coefficient is determined during the calibration stage by nonlinearly fitting the corrected transmission signal amplitude of all standard samples and their corresponding known concentration values. After the fitting is completed, the coefficient is fixedly stored in the memory inside the probe.

[0058] The coefficient of the first term is a constant used to describe the weight of the first term in the entire fractional mapping relationship for correcting the amplitude of the transmitted signal. This coefficient is also determined through a nonlinear fitting process and together with the coefficient of the second term, constitutes the polynomial in the molecule concerning the amplitude of the corrected transmitted signal.

[0059] The molecule constant term is a fixed value in the molecule polynomial that does not depend on the amplitude of the corrected transmission signal. This constant is determined through a nonlinear fitting process and is used to compensate for the reference offset of the molecule polynomial when the amplitude is zero.

[0060] The coefficient of the first-order term in the denominator is the weighting constant corresponding to the first-order term in the denominator polynomial that corrects the amplitude of the transmitted signal. This coefficient is determined through a nonlinear fitting process and together with the constant term in the denominator, constitutes the linear expression of the denominator.

[0061] The denominator constant term is a fixed value in the denominator polynomial that does not depend on the amplitude of the corrected transmitted signal. This constant is determined through a nonlinear fitting process to ensure that the denominator is not zero when the amplitude is zero.

[0062] The global offset is a fixed value added after the entire fractional operation is completed. This offset is determined through a nonlinear fitting process and is used to adjust the overall numerical range of the calculation results to match the actual concentration values.

[0063] The transmission concentration data of the sample to be tested is the final concentration value that needs to be calculated. This value is obtained by substituting the amplitude of the corrected transmission signal obtained from the detection of the sample into the above fractional mapping relationship and performing a complete calculation.

[0064] First, the amplitude of the corrected transmission signal is squared to obtain a squared value. This squared value is then multiplied by the coefficient of the quadratic term to obtain the first product. Simultaneously, the amplitude of the corrected transmission signal is multiplied by the coefficient of the linear term to obtain the second product. The first and second products are then added to the numerator constant term to obtain the numerator sum. Next, the amplitude of the corrected transmission signal is multiplied by the coefficient of the linear term in the denominator to obtain the third product. This third product is then added to the denominator constant term to obtain the denominator sum. Finally, the numerator sum is divided by the denominator sum to obtain the fractional result. Finally, the fractional result is added to the global offset to obtain the final value, which is the transmission concentration data of the sample to be measured.

[0065] The beneficial effects are as follows: By comparing the transmission signal intensity within a range using preset effective transmission and reflection thresholds, the concentration state of the sample to be tested is clearly divided into a transmission-dominant region, a reflection-dominant region, and a smooth transition region, achieving automatic identification and partitioning of different concentration ranges; by acquiring the correction signal of a standard sample with known concentration and performing nonlinear fitting, a mapping relationship between the correction signal and the actual concentration is established. This mapping relationship is stored inside the probe in the form of a continuous curve, enabling the rapid acquisition of concentration data through simple curve lookup during subsequent detection; depending on the different concentration distribution states, the corresponding mapping relationship is selected for single-path or dual-path analysis. In the transmission-dominant region, only the transmission mapping relationship is used to avoid noise introduced by the reflection signal; in the reflection-dominant region, only the reflection mapping relationship is used to avoid transmission signal failure; in the smooth transition region, both analysis results are retained simultaneously, ensuring the accuracy of concentration data within each concentration range and providing two aligned concentration data sources for subsequent smooth fusion.

[0066] S5. The transmission concentration data and the reflection concentration data are smoothly spliced ​​and fused to obtain the transition region concentration data of the sample to be tested; In this embodiment of the invention, the step of smoothly stitching and fusing the transmission concentration data and the reflection concentration data to obtain the transition region concentration data of the sample to be tested includes: Using the effective reflection threshold and the effective transmission threshold as interval benchmarks, the relative position weight analysis is performed on the transmission signal intensity to obtain the transmission fusion coefficient and the reflection fusion coefficient of the transmission signal intensity; Based on the transmission fusion coefficient and the reflection fusion coefficient, the transmission concentration data and the reflection concentration data are factor-weighted and synthesized to obtain the first fusion component and the second fusion component of the transmission concentration data and the reflection concentration data; The first fusion component and the second fusion component are accumulated and merged to obtain the transition region concentration data of the sample to be tested.

[0067] Using the effective reflection threshold and the effective transmission threshold as interval benchmarks, the relative position weighting of the transmitted signal intensity is analyzed to obtain the transmission fusion coefficient and the reflection fusion coefficient of the transmitted signal intensity. This operation is only performed when the concentration distribution of the sample under test is identified as a smooth transition region. First, the difference between the effective transmission threshold and the effective reflection threshold is calculated as the total length of the entire interval. Then, the difference between the actual value of the transmitted signal intensity and the effective reflection threshold is calculated as the offset of the transmitted signal intensity within the interval. Then, this offset is divided by the total length of the entire interval to obtain a proportional value, which is the transmission fusion coefficient. The transmission fusion coefficient reflects the degree to which the current transmitted signal intensity is close to the effective transmission threshold within the transition interval. Then, a fixed value is subtracted from the transmission fusion coefficient to obtain the reflection fusion coefficient. The reflection fusion coefficient reflects the degree to which the current transmitted signal intensity is close to the effective reflection threshold within the transition interval. The sum of the transmission fusion coefficient and the reflection fusion coefficient is always equal to this fixed value.

[0068] Based on the transmission fusion coefficient and the reflection fusion coefficient, the transmission concentration data and the reflection concentration data are factor-weighted and synthesized to obtain the first fusion component and the second fusion component of the transmission concentration data and the reflection concentration data. The transmission concentration data of the sample to be tested is multiplied by the transmission fusion coefficient to obtain a product result, which is the first fusion component. The reflection concentration data of the sample to be tested is multiplied by the reflection fusion coefficient to obtain another product result, which is the second fusion component. The first fusion component represents the contribution of the transmission concentration data in the current fusion operation, and the second fusion component represents the contribution of the reflection concentration data in the current fusion operation. The larger the transmission fusion coefficient, the larger the proportion of the first fusion component, and the larger the reflection fusion coefficient, the larger the proportion of the second fusion component.

[0069] The first fusion component and the second fusion component are accumulated and merged to obtain the transition region concentration data of the sample to be tested. The calculated values ​​of the first fusion component and the second fusion component are directly added together, and the result is the transition region concentration data. When the transmission signal intensity is close to the effective transmission threshold, the transition region concentration data mainly reflects the characteristics of transmission concentration data. When the transmission signal intensity is close to the effective reflection threshold, the transition region concentration data mainly reflects the characteristics of reflection concentration data. When the transmission signal intensity is in the middle of the interval, it takes into account the joint contribution of transmission concentration data and reflection concentration data, thus realizing a smooth transition from the transmission-dominant region to the reflection-dominant region.

[0070] The beneficial effects are as follows: using fixed effective reflection and transmission thresholds as interval benchmarks provides a clear and reproducible mathematical basis for calculating the transmission fusion coefficient and reflection fusion coefficient, ensuring the comparability of fusion coefficients between different samples and different detection batches; the two fusion coefficients obtained through relative position weight analysis reflect the precise position of the current transmission signal intensity within the transition interval, with the fusion coefficient being larger on the side closer to it, achieving adaptive weight allocation for different positions within the transition zone; by multiplying the transmission concentration data and reflection concentration data by the corresponding fusion coefficients through factor weighted synthesis, the first and second fusion components are precisely matched with the current signal intensity position; by accumulating and normalizing the two fusion components and combining them into a single transition zone concentration data, this data can naturally connect with the output data of the transmission-dominant and reflection-dominant zones at both ends of the transition zone, eliminating the data jumps and discontinuities between different concentration intervals in traditional detection methods, and ensuring the continuity and smoothness of detection results across the entire concentration range.

[0071] S6. Optimize the reliability of the transmission concentration data, the reflection concentration data, and the transition region concentration data to confirm the optical density of the sample to be tested.

[0072] In this embodiment of the invention, the step of performing reliability optimization on the transmission concentration data, the reflection concentration data, and the transition region concentration data to confirm the optical density of the sample to be tested includes: Fluctuation deviation analysis was performed on the transmission concentration data to obtain the time-series stability coefficient of the transmission concentration data; The original reflected electrical signal corresponding to the reflected concentration data is evaluated by signal-to-noise separation to obtain the signal-to-noise margin coefficient of the reflected concentration data. The weighting ratio of the transmission fusion coefficient and the reflection fusion coefficient is determined to obtain the fusion balance coefficient of the transition region concentration data; The optical density of the sample under test is confirmed based on the time stability coefficient, the signal-to-noise margin coefficient, and the fusion balance coefficient.

[0073] All transmission concentration data of the sample under test obtained in a continuous detection period are arranged into a time series according to the sampling time. The arithmetic mean of all data in the series is calculated. Then, the absolute value of the deviation between each data and the arithmetic mean is calculated. The absolute values ​​of all deviations are summed and divided by the total number of data to obtain the average deviation. The ratio of the average deviation to the arithmetic mean is then subtracted from a fixed value. The result is the time series stability coefficient, which reflects the degree of fluctuation of the transmission concentration data on the time axis. The larger the coefficient, the more stable the transmission concentration data.

[0074] The original reflected electrical signal is an analog quantity of the reflected channel obtained directly in the photoelectric detection and conversion step without any correction processing. This original reflected electrical signal is sent to a frequency band separation circuit composed of a high-pass filter and a low-pass filter. The high-pass filter extracts the high-frequency components of the signal as noise components, and the low-pass filter extracts the low-frequency components of the signal as effective signal components. The power values ​​of the effective signal components and the noise components are measured respectively. The power value of the effective signal components is divided by the sum of the power values ​​of the effective signal components and the noise components. The result is the signal-to-noise margin coefficient. This coefficient reflects the proportion of effective signal in the original reflected electrical signal. The larger the coefficient, the better the quality of the reflected signal.

[0075] The transmission fusion coefficient and the reflection fusion coefficient are two coefficients calculated in the smooth stitching fusion step. The values ​​of the transmission fusion coefficient and the reflection fusion coefficient are compared, and the absolute difference between the two is calculated. Then, a fixed value is subtracted from the absolute difference, and the result is the fusion balance coefficient. This coefficient reflects the degree of closeness between the two fusion coefficients. The larger the coefficient, the closer the values ​​of the transmission fusion coefficient and the reflection fusion coefficient are, that is, the closer the current transition zone position is to the middle position between the effective transmission threshold and the effective reflection threshold.

[0076] The three values—temporal stability coefficient, signal-to-noise margin coefficient, and fusion balance coefficient—are each compared with a pre-set judgment threshold. This judgment threshold is determined statistically based on a large amount of actual sample detection data during probe factory calibration. When a coefficient is greater than or equal to the judgment threshold and is the maximum value among the three coefficients, the concentration data corresponding to that coefficient is used as the optical density output of the sample to be tested. Specifically, the temporal stability coefficient corresponds to the transmission concentration data, the signal-to-noise margin coefficient corresponds to the reflection concentration data, and the fusion balance coefficient corresponds to the transition region concentration data. When two or three coefficients simultaneously meet the condition of being greater than or equal to the judgment threshold and simultaneously being the maximum value, the transmission concentration data is uniformly selected as the final optical density output.

[0077] The beneficial effects are as follows: By evaluating the signal-to-noise ratio of the original reflected electrical signal, the signal-to-noise adequacy coefficient is obtained, which quantitatively evaluates the proportion of effective components in the reflected signal and avoids the use of unreliable reflection data when the reflected signal is submerged in noise; by determining the weight ratio of the transmission fusion coefficient and the reflection fusion coefficient, the fusion balance coefficient is obtained, which quantitatively evaluates the balance of the fusion weight in the transition region and reflects the dependence balance of the concentration data in the transition region on the two signals; by comparing the three coefficients with the judgment threshold and selecting the data corresponding to the maximum value as the final output, an adaptive optimization mechanism is realized that transmission data is given priority when the transmission data is stable, reflection data is given priority when the quality of the reflected signal is high, and fusion data is given priority when the weight in the transition region is balanced. This ensures that the output optical density under any concentration condition is the most reliable and trustworthy data under the current detection state.

[0078] like Figure 2 The diagram shown is a functional block diagram of an immersion dual-mode optical density detection system provided in an embodiment of the present invention.

[0079] The immersion dual-mode optical density detection system 100 described in this invention can be installed in an electronic device. Depending on the functions implemented, the immersion dual-mode optical density detection system 100 may include a dual-optical path construction module 101, a photoelectric conversion and acquisition module 102, a common-mode cancellation correction module 103, a partition compensation mapping module 104, a transition region fusion module 105, and a reliability optimization output module 106. The module described in this invention can also be referred to as a unit, which refers to a series of computer program segments that can be executed by the processor of an electronic device and can perform a fixed function, and are stored in the memory of the electronic device.

[0080] In this embodiment, the functions of each module / unit are as follows: The dual-optical-path construction module 101 is used to split the single-beam detection light emitted by the light source into a reference beam and a measurement beam, and to couple the measurement beam into the immersion fiber optic probe to illuminate the sample to be tested. The photoelectric conversion acquisition module 102 is used to perform photoelectric detection conversion on the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test, to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source. The common-mode cancellation correction module 103 is used to perform common-mode component cancellation on the transmitted electrical signal and the reflected electrical signal using the reference electrical signal as the fluctuation correction reference, so as to obtain the concentration signal pair of the sample to be tested; The partition compensation mapping module 104 is used to identify the concentration distribution of the sample to be tested based on the concentration signal pair, and to perform dual-path fractional nonlinear compensation on the concentration signal pair based on the identification result, so as to obtain the transmission concentration data and reflection concentration data of the sample to be tested. The transition region fusion module 105 is used to smoothly stitch and fuse the transmission concentration data and the reflection concentration data to obtain the transition region concentration data of the sample to be tested. The confidence optimization output module 106 is used to perform confidence optimization on the transmission concentration data, the reflection concentration data and the transition region concentration data to confirm the optical density of the sample to be tested.

[0081] In the several embodiments provided by this invention, it should be understood that the disclosed probes and systems can be implemented in other ways. For example, the system embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0082] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0083] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0084] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0085] The embodiments of this application can acquire and process relevant data based on an artificial intelligence technology. Artificial intelligence is a theory, probe, technology, and application system that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. An immersion dual-mode optical density detection probe, characterized in that, The probe includes: S1. The single-beam detection light emitted by the light source is split into a reference beam and a measurement beam, and the measurement beam is coupled and incident on the immersion fiber optic probe to illuminate the sample to be tested; S2. Perform photoelectric detection conversion on the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source. S3. Using the reference electrical signal as the fluctuation correction benchmark, common-mode component cancellation is performed on the transmitted electrical signal and the reflected electrical signal to obtain the concentration signal pair of the sample to be tested; S4. Based on the concentration signal pair, the concentration distribution of the sample to be tested is identified, and based on the identification result, dual-path nonlinear compensation is performed on the concentration signal pair to obtain the transmission concentration data and reflection concentration data of the sample to be tested. S5. The transmission concentration data and the reflection concentration data are smoothly spliced ​​and fused to obtain the transition region concentration data of the sample to be tested; S6. Optimize the reliability of the transmission concentration data, the reflection concentration data, and the transition region concentration data to confirm the optical density of the sample to be tested.

2. The immersion dual-mode optical density detection probe as described in claim 1, characterized in that, The step of splitting the single-beam detection light emitted from the light source into a reference beam and a measurement beam, and coupling the measurement beam to be incident on an immersion fiber optic probe to illuminate the sample to be tested, includes: According to a preset fixed ratio, the single beam of detection light emitted by the light source is optically decoupled to obtain the reference beam and the measurement beam of the light source. The beam diameter of the measurement beam is adjusted to obtain a focused transmission beam. The sample to be tested is illuminated by the focused transmission beam.

3. The immersion dual-mode optical density detection probe as described in claim 1, characterized in that, The process of photoelectric detection and conversion of the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source includes: Based on the same time reference, parallel photoelectric sampling is performed on the reference beam, forward transmitted light and backscattered light of the light source to obtain the original reference analog quantity, original transmission analog quantity and original reflection analog quantity of the light source; Gain adaptation adjustment is performed on the original reference analog quantity, the original transmission analog quantity, and the original reflection analog quantity to obtain the adjusted reference analog quantity, the adjusted transmission analog quantity, and the adjusted reflection analog quantity of the light source. The adjusted reference analog quantity, the adjusted transmission analog quantity, and the adjusted reflection analog quantity are converted from analog to digital to obtain the reference electrical signal, transmission electrical signal, and reflection electrical signal of the light source.

4. The immersion dual-mode optical density detection probe as described in claim 1, characterized in that, The step of using the reference electrical signal as a fluctuation correction benchmark to perform common-mode component cancellation on the transmitted electrical signal and the reflected electrical signal to obtain the concentration signal pair of the sample to be tested includes: Extract the instantaneous amplitude of the reference electrical signal in a continuous time series to construct a reference fluctuation feature sequence of the reference electrical signal; Based on the reference fluctuation characteristic sequence, common-mode suppression calibration is performed on the transmitted electrical signal and the reflected electrical signal to obtain the transmission channel correction and reflection channel correction of the transmitted electrical signal and the reflected electrical signal; Based on the time-domain characteristics of the reference electrical signal, the transmission channel correction and the reflection channel correction are correlated and configured to obtain the concentration signal pair of the sample to be tested.

5. The immersion dual-mode optical density detection probe as described in claim 1, characterized in that, The step of identifying the concentration distribution of the sample to be tested based on the concentration signal pair includes: Component focusing evaluation is performed on the concentration signal pair to obtain the transmission signal intensity of the concentration signal pair; The intensity of the transmitted signal is compared with a preset effective transmission threshold and a preset effective reflection threshold within a certain range. When the intensity of the transmitted signal is higher than the effective transmission threshold, the concentration distribution of the sample to be tested is identified as the transmission-dominant region. When the intensity of the transmitted signal is lower than the effective reflection threshold, the concentration distribution of the sample to be tested is identified as the reflection-dominant region. When the intensity of the transmitted signal is between the effective reflection threshold and the effective transmission threshold, the concentration distribution state of the sample to be tested is identified as a smooth transition region.

6. The immersion dual-mode optical density detection probe as described in claim 5, characterized in that, Based on the identification results, dual-path fractional nonlinear compensation is performed on the concentration signal pair to obtain the transmission concentration data and reflectance concentration data of the sample under test, including: Obtain the corrected transmission signal and corrected reflection signal corresponding to the irradiation of a standard sample of known concentration; The corrected transmission signal and the corrected reflection signal are nonlinearly fitted with the known concentration value of the known concentration standard sample to obtain a first fractional mapping relationship and a second fractional mapping relationship between the corrected transmission signal and the corrected reflection signal and the known concentration value; When the concentration distribution state is identified as a transmission-dominant region, the transmission concentration data of the sample to be tested is calculated based on the first fractional mapping relationship. When the concentration distribution state is identified as a reflection-dominant region, based on the second fractional mapping relationship, the fitting parameters of the corrected reflection signal in the concentration signal pair are derived to obtain the reflection concentration data of the sample to be tested. When the concentration distribution state is identified as a smooth transition region, based on the first fractional mapping relationship and the second fractional mapping relationship, dual-path parametric analysis is performed on the corrected transmission signal and corrected reflection signal in the concentration signal pair to obtain the transition region transmission concentration data and transition region reflection concentration data of the sample to be tested. The transmission concentration data and the reflection concentration data of the transition region are used as the transmission concentration data and reflection concentration data of the sample to be tested.

7. The immersion dual-mode optical density detection probe as described in claim 6, characterized in that, The formula for calculating the reflectance concentration data is as follows: ； In the formula, The transmission concentration data of the sample to be tested. The amplitude of the corrected transmission signal. Let be the coefficient of the quadratic term in the first fractional mapping relationship. Let be the coefficient of the first-order term in the first fractional mapping relationship. This is the numerator constant term of the first fractional mapping relationship. Let be the coefficient of the linear term in the denominator of the first fractional mapping relationship. The constant term in the denominator of the first fractional mapping relationship is... This is the global offset of the first fractional mapping relationship.

8. The immersion dual-mode optical density detection probe as described in claim 5, characterized in that, The process of smoothly stitching and fusing the transmission concentration data and the reflection concentration data to obtain the transition region concentration data of the sample to be tested includes: Using the effective reflection threshold and the effective transmission threshold as interval benchmarks, the relative position weight analysis is performed on the transmission signal intensity to obtain the transmission fusion coefficient and the reflection fusion coefficient of the transmission signal intensity; Based on the transmission fusion coefficient and the reflection fusion coefficient, the transmission concentration data and the reflection concentration data are factor-weighted and synthesized to obtain the first fusion component and the second fusion component of the transmission concentration data and the reflection concentration data; The first fusion component and the second fusion component are accumulated and merged to obtain the transition region concentration data of the sample to be tested.

9. The immersion dual-mode optical density detection probe as described in claim 8, characterized in that, The process of optimizing the reliability of the transmission concentration data, the reflection concentration data, and the transition region concentration data to confirm the optical density of the sample under test includes: Fluctuation deviation analysis was performed on the transmission concentration data to obtain the time-series stability coefficient of the transmission concentration data; The original reflected electrical signal corresponding to the reflected concentration data is evaluated by signal-to-noise separation to obtain the signal-to-noise margin coefficient of the reflected concentration data. The weighting ratio of the transmission fusion coefficient and the reflection fusion coefficient is determined to obtain the fusion balance coefficient of the transition region concentration data; The optical density of the sample under test is confirmed based on the time stability coefficient, the signal-to-noise margin coefficient, and the fusion balance coefficient.

10. An immersion dual-mode optical density detection system, characterized in that, The system for implementing the immersion dual-mode optical density detection probe of claim 1 includes: The dual-optical-path construction module is used to split the single-beam detection light emitted by the light source into a reference beam and a measurement beam, and couple the measurement beam into the immersion fiber optic probe to illuminate the sample to be tested; The photoelectric conversion acquisition module is used to perform photoelectric detection and conversion on the reference beam, the forward transmitted light after passing through the sample under test, and the light reflected backward by the sample under test, to obtain the reference electrical signal, the transmitted electrical signal, and the reflected electrical signal of the light source. The common-mode cancellation correction module is used to cancel the common-mode components of the transmitted electrical signal and the reflected electrical signal using the reference electrical signal as the fluctuation correction reference, so as to obtain the concentration signal pair of the sample to be tested; The partition compensation mapping module is used to identify the concentration distribution of the sample to be tested based on the concentration signal pair, and to perform dual-path fractional nonlinear compensation on the concentration signal pair based on the identification result, so as to obtain the transmission concentration data and reflection concentration data of the sample to be tested. The transition region fusion module is used to smoothly stitch and fuse the transmission concentration data and the reflection concentration data to obtain the transition region concentration data of the sample to be tested. The confidence optimization output module is used to perform confidence optimization on the transmission concentration data, the reflection concentration data and the transition region concentration data to confirm the optical density of the sample to be tested.

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