Reflected light intensity correction method of photoelectric sensor and photoelectric sensor

Abstract

The invention discloses a photoelectric sensor reflected light intensity correction method and a photoelectric sensor, and the method comprises the steps: S1, building a multivariable dynamic correction model which is based on a physical principle and experimental data, the comprehensive influence of the environment temperature and the self-heating effect of the photoelectric sensor on the performance of the photoelectric sensor is fused; s2, implementing a real-time monitoring system to continuously obtain the environment temperature, the core temperature of the photoelectric sensor and the uncorrected reflected light intensity measured by the photoelectric sensor; and S3, calculating and outputting the corrected reflected light intensity in real time by using the multivariable dynamic correction model. The multivariable dynamic correction model dynamically adjusts each parameter to adapt to changes of actual measurement conditions, and high precision and stability of output data are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of optical sensors, and in particular to a method for calibrating the intensity of reflected light of a photoelectric sensor and the photoelectric sensor. Background Art

[0002] The photoelectric sensors in the prior art are affected by changes in ambient temperature, and the measurement results of reflected light intensity will be affected, resulting in inaccurate jaundice assessment.

[0003] Specifically, transcutaneous jaundice instruments are widely used in non-invasive detection of neonatal jaundice, which evaluates the bilirubin level in the body by measuring the intensity of light reflected from the skin. However, due to changes in ambient temperature, the reflected light intensity measurement results will be affected, resulting in inaccurate jaundice assessment. Although some studies have attempted to reduce this error through temperature compensation methods, most existing technologies have problems such as low correction accuracy and poor real-time performance.

[0004] Furthermore, most of the blood oxygen sensors on the market are actually photoelectric sensors. The principle of measuring data is similar to that of the above-mentioned jaundice meter, which estimates the oxygen saturation in the blood by measuring and calculating the intensity of reflected light (the difference is that the blood oxygen meter uses a different light band). Therefore, the blood oxygen meter is also affected by temperature changes, resulting in inaccurate measurements.

[0005] For example, some methods are only applicable to specific types of sensors or to application scenarios that do not require high real-time performance. Therefore, there is an urgent need for a temperature compensation correction method that can adapt to a variety of environmental conditions and has high accuracy.

[0006] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0007] The present invention provides a method for calibrating the reflected light intensity of a photoelectric sensor and a photoelectric sensor, which can solve at least one problem in the background technology.

[0008] A method for correcting the reflected light intensity of a photoelectric sensor comprises the following steps: S1: constructing a multivariable dynamic correction model, wherein the multivariable dynamic correction model is based on physical principles and experimental data and integrates the comprehensive influence of ambient temperature and the self-heating effect of the photoelectric sensor on the performance of the photoelectric sensor; S2: implementing a real-time monitoring system to continuously obtain the ambient temperature, the core temperature of the photoelectric sensor and the uncorrected reflected light intensity measured by the photoelectric sensor; S3: applying the multivariable dynamic correction model to calculate and output the corrected reflected light intensity in real time.

[0009] Preferably, the multivariable dynamic correction model includes a nonlinear function for describing the variation of the light intensity of the light source with temperature, and the nonlinear function is optimized based on the light source characteristics and environmental factors.

[0010] Preferably, the method further comprises responding to a rapid change in the internal temperature of the photosensor.

[0011] Preferably, the multivariable dynamic correction model includes the thermal response characteristics of the photoelectric sensor determined by experiments, and the direct and indirect effects of ambient temperature on the performance of the photoelectric sensor.

[0012] Preferably, the method further comprises: regularly updating and optimizing the multivariable dynamic correction model using machine learning technology.

[0013] Preferably, the multivariate dynamic correction model includes an algorithm for adjusting correction parameters in real time.

[0014] The present invention also provides a photoelectric sensor, which adopts any of the above-mentioned methods for correcting the reflected light intensity of the photoelectric sensor.

[0015] Preferably, the photoelectric sensor is a transcutaneous icterometer or a blood oximeter.

[0016] The present invention also provides a photoelectric sensor for collecting skin reflected light signals, comprising: a processor for processing data using the reflected light intensity correction method of any of the photoelectric sensors described above; a data collection unit for continuously collecting ambient temperature and the core temperature of the photoelectric sensor; and an output interface for displaying or transmitting corrected reflected light intensity data.

[0017] Preferably, it further comprises: a real-time monitoring system, the real-time monitoring system comprising an independent calibration unit for the sensor temperature, the independent calibration unit responding to the rapid change of the internal temperature of the photoelectric sensor.

[0018] The present invention provides a comprehensive multivariable dynamic correction model that comprehensively considers the effects of ambient temperature, instrument self-heating, and temperature characteristics of multiple light sources and detectors on the intensity of reflected light. The multivariable dynamic correction model dynamically adjusts various parameters to adapt to changes in actual measurement conditions, ensuring high accuracy and stability of output data.

[0019] Furthermore, the method of the present invention is easy to integrate and implement: the method of the present invention can be easily integrated into an embedded system through a low-level programming language (such as C language), and only a small amount of code needs to be updated and necessary algorithm parameters need to be added.

[0020] Furthermore, the method of the present invention has wide applicability: the temperature compensation correction method of the present invention is not only applicable to specific optical sensors, but also has good versatility. Its nonlinear correction method can be used in various types of optical detection equipment, especially in the detection equipment of neonatal jaundice, which can effectively improve the measurement accuracy and reduce the influence of ambient temperature on the detection results. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of a method for calibrating reflected light intensity of a photoelectric sensor according to an embodiment of the present invention.

[0022] Figure 2 Schematic diagram of a photoelectric sensor for collecting skin reflected light signals according to an embodiment of the present invention.

[0023] Figure 3 The figure is a comparison of the bilirubin values ​​of two subjects before and after being treated by the method of the present invention in the example of the present invention. DETAILED DESCRIPTION

[0024] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention. In the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other.

[0025] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, connection can be used for fixing as well as for coupling or communication.

[0026] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0028] See also Figure 1 An embodiment of the present invention provides a method for calibrating the reflected light intensity of a photoelectric sensor, comprising the following steps: S1: construct a multivariable dynamic correction model, which is based on physical principles and experimental data and integrates the comprehensive influence of ambient temperature and the self-heating effect of the photoelectric sensor on the performance of the photoelectric sensor; S2: implementing a real-time monitoring system to continuously acquire the ambient temperature, the core temperature of the photoelectric sensor, and the uncorrected reflected light intensity measured by the photoelectric sensor; S3: Apply the multivariable dynamic correction model to calculate and output the corrected reflected light intensity in real time.

[0029] The present invention provides a comprehensive multivariable dynamic correction model that comprehensively considers the effects of ambient temperature, instrument self-heating, and temperature characteristics of multiple light sources and detectors on the intensity of reflected light. The multivariable dynamic correction model dynamically adjusts various parameters to adapt to changes in actual measurement conditions, ensuring high accuracy and stability of output data.

[0030] The present invention proposes a reflected light intensity correction method, which can accurately correct the light intensity reading under various ambient temperatures and the instrument's own heating conditions to ensure the accuracy and consistency of the measurement results. The method is particularly suitable for medical devices that measure light intensity with high precision, such as transcutaneous icterometers, oximeters, and other wearable medical monitoring devices, where accurate light intensity readings are crucial for clinical diagnosis.

[0031] In one embodiment of the present invention, the photoelectric sensor is a transcutaneous icterus instrument or a blood oximeter, or other medical monitoring equipment using other photoelectric sensors that measure by measuring and calculating the intensity of reflected light, and the present invention does not make any limitation thereto.

[0032] In one embodiment of the present invention, the multivariable dynamic correction model includes a nonlinear function for describing the variation of the light intensity of the light source with temperature, and the nonlinear function is optimized based on the light source characteristics and environmental factors.

[0033] In a specific embodiment, the multivariable dynamic correction model is a nonlinear equation, including calculation and calibration of multiple situations; the situations include the influence of ambient temperature, the thermal influence of the photoelectric sensor working heat, the light source response and the photoelectric sensor detector response.

[0034] In one embodiment of the present invention, the multivariable dynamic correction model of the present invention is responsive to rapid changes in the internal temperature of the photosensor.

[0035] In a specific embodiment of the present invention, a multivariate dynamic correction model is provided with the following specific steps: 1. Model variables: T_env: ambient temperature (°C) T_sensor: sensor temperature (°C) T_light_i: temperature of the ith light source (°C) (i = 1, 2, ... n, where n is the number of light sources) I_light_i_0: initial light intensity of the i-th light source at the reference temperature R_i: Initial reflected light intensity of the i-th light source S_j_0: initial sensitivity of the jth detector at the reference temperature (j = 1, 2, ... m, where m is the number of detectors) 2. Component characteristic function: In order to accurately reflect the temperature characteristics of components, the present invention introduces the following functions, the specific forms of which need to be determined based on experimental data fitting, for example, polynomial functions or exponential functions can be used: f_light_i(T_light_i): The temperature characteristic function of the i-th light source, describing the change of the light intensity of the light source with temperature: f_light_i(T_light_i) = I_light_i_0 * (1 - k_light_i * T_light_i + l_light_i * T_light_i^2 + m_light_i * exp(-n_light_i * T_light_i)) Among them, k_light_i, l_light_i, m_light_i, and n_light_i are coefficients related to the light source and need to be determined through experiments. The introduction of exponential terms increases the nonlinearity of the model and simulates the actual situation more accurately.

[0036] f_detector_j(T_sensor): The temperature characteristic function of the jth detector, describing the change of detector sensitivity with temperature: f_detector_j(T_sensor) = S_j_0 * (1 + k_detector_j * T_sensor + l_detector_j * T_sensor^2) Among them, k_detector_j and l_detector_j are coefficients related to the detector and need to be determined through experiments.

[0037] f_env(T_env): Function of the effect of ambient temperature on light intensity, for example, considering the effect of ambient temperature on light propagation (absorption and scattering): f_env(T_env) = exp(-(c1*T_env + c2*T_env^2)) Among them, c1 and c2 are coefficients that need to be determined through experiments.

[0038] 3. Multivariate dynamic correction model: The corrected reflected light intensity R_i_corrected can be expressed as: R_i_corrected=f_light_i(T_light_i)*f_env(T_env)*f_detector_j(T_sensor) * R_i This formula takes into account the temperature characteristics of the light source, the influence of the ambient temperature, the temperature characteristics of the detector, and the initial reflected light intensity.

[0039] 4. Model building steps: Step S1: Set a series of test temperature points to cover the possible range of ambient temperature and sensor operating temperature.

[0040] Step S2: The sensor and its measurement environment are heated and cooled to simulate temperature fluctuations in actual applications.

[0041] Step S3: Under the premise of ensuring that the measurement positions are consistent, multiple measurements are performed on each temperature point to obtain reflected light intensity data.

[0042] Step S4: Use the experimental data to fit the above f_light_i, f_detector_j, and f_env functions and determine the coefficients therein.

[0043] Step S5: Apply the comprehensive mathematical model to correct the initial reflected light intensity to obtain the corrected light intensity.

[0044] Furthermore, the multivariable dynamic correction model of the present invention further considers the unique thermal response characteristics of the sensor determined by experiments, as well as the direct and indirect effects of the ambient temperature on the sensor performance.

[0045] In order to adapt to changes in the environment and sensor performance during long-term operation, the reflected light intensity correction method of the present invention uses machine learning technology to regularly update and optimize the multivariable dynamic correction model.

[0046] The present invention also provides a photoelectric sensor, which adopts any of the above-mentioned methods for correcting the reflected light intensity of the photoelectric sensor.

[0047] like Figure 2 As shown, the present invention provides a photoelectric sensor for collecting skin reflected light signals, comprising: A processor for processing data using the reflected light intensity correction method of the photoelectric sensor as described above; a data collection unit, used for continuously collecting the ambient temperature and the core temperature of the photoelectric sensor; An output interface is used to display or transmit the corrected reflected light intensity data.

[0048] Furthermore, the photoelectric sensor of the present invention further comprises: a real-time monitoring system, wherein the real-time monitoring system comprises an independent calibration unit for the sensor temperature, wherein the independent calibration unit responds to rapid changes in the internal temperature of the photoelectric sensor.

[0049] like Figure 3 As shown, in a specific embodiment, the method of the present invention is applied to a photoelectric sensor, and the photoelectric sensor can be a transcutaneous jaundice instrument. Transcutaneous jaundice instruments are widely used in non-invasive detection of neonatal jaundice, and the bilirubin level in the body is evaluated by measuring the intensity of light reflected from the skin. The two pictures in the first column show two experimenters: experimenter No. 1 and experimenter No. 2, before being treated by the method of the present invention, the bilirubin values ​​measured by the instrument at the same position are obtained. From the figure, it can be seen that the bilirubin values ​​measured by the two experimenters will be affected by the change of the measurement temperature, resulting in a large difference in the measured values; the second column shows the bilirubin values ​​measured by the instrument at the same position after the two experimenters were treated by the method of the present invention. It is obvious that the curves after treatment tend to be flat. It can be seen that the transcutaneous jaundice instrument using the method of the present invention will not be affected by the change of ambient temperature and affect the measurement result of the reflected light intensity. The correction cost of the present invention is low, the accuracy is high and the real-time performance is good.

[0050] Furthermore, the photoelectric sensor of the present invention performs more stably and reliably in long-term continuous operation and has significant cost advantages.

[0051] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, without departing from the concept of the present invention, it can also make several substitutions or modifications to these described embodiments, and these substitutions or modifications should be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description of the reference terms "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In the absence of mutual contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A method for calibrating the reflected light intensity of a photoelectric sensor, characterized in that: The steps include: S1: construct a multivariable dynamic correction model, which is based on physical principles and experimental data and integrates the comprehensive influence of ambient temperature and the self-heating effect of the photoelectric sensor on the performance of the photoelectric sensor; S2: implementing a real-time monitoring system to continuously acquire the ambient temperature, the core temperature of the photoelectric sensor, and the uncorrected reflected light intensity measured by the photoelectric sensor; S3: Apply the multivariable dynamic correction model to calculate and output the corrected reflected light intensity in real time.

2. The method for calibrating the reflected light intensity of a photoelectric sensor according to claim 1, wherein: The multivariable dynamic correction model includes a nonlinear function for describing the variation of the light intensity of the light source with temperature, and the nonlinear function is optimized based on the light source characteristics and environmental factors.

3. The method for calibrating the reflected light intensity of a photoelectric sensor according to claim 1 or 2, characterized in that: Also included is responding to rapid changes in temperature within the photosensor.

4. The method for calibrating the reflected light intensity of a photoelectric sensor according to claim 3, wherein: The multivariable dynamic correction model includes the thermal response characteristics of the photoelectric sensor determined by experiments, as well as the direct and indirect effects of ambient temperature on the performance of the photoelectric sensor.

5. The method for calibrating the reflected light intensity of a photoelectric sensor according to claim 3, wherein: Also includes: The multivariate dynamic correction model is regularly updated and optimized using machine learning techniques.

6. The method for calibrating the reflected light intensity of a photoelectric sensor according to claim 3, wherein: The multivariable dynamic correction model includes an algorithm for adjusting correction parameters in real time.

7. A photoelectric sensor, characterized in that: A method for correcting the reflected light intensity of a photoelectric sensor as described in any one of claims 1 to 6 is adopted.

8. The method for calibrating the reflected light intensity of a photoelectric sensor according to claim 6, wherein: The photoelectric sensor is a transcutaneous icterometer or a blood oximeter.

9. A photoelectric sensor for collecting skin reflected light signals, characterized in that: include: A processor, configured to process data using the reflected light intensity correction method of the photoelectric sensor as described in any one of claims 1 to 6; a data collection unit, used for continuously collecting the ambient temperature and the core temperature of the photoelectric sensor; An output interface is used to display or transmit the corrected reflected light intensity data.

10. The photoelectric sensor for collecting skin reflected light signals according to claim 9, characterized in that: Also includes: A real-time monitoring system includes an independent calibration unit for sensor temperature, the independent calibration unit responding to rapid changes in the internal temperature of the photosensor.

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