Calibration method, device and equipment for detection range of optical sensor and medium

Abstract

The embodiment of the invention provides a calibration method, device, equipment and medium for the detection range of an optical sensor, and the method comprises the following steps: constructing a spectrum correction curve of the optical sensor, and determining the illumination intensity of a light source according to the spectrum correction curve; the light beam with the initial reference illumination intensity is split through a light splitting system, and spectral data of light signals with different wavelengths are generated; converting the spectral data into an electric signal, preprocessing the electric signal to generate a preprocessed electric signal, determining the response range of the optical sensor through the preprocessed electric signal, and determining the detection range of the optical sensor through the response range; and judging whether the detection range meets the precision requirement, if so, ending the calibration of the detection range, and if not, changing the illumination intensity of the light source by adjusting the voltage of the light source driving power supply, and re-calibrating the detection range of the optical sensor. According to the scheme, the measuring range of the optical sensor can be calibrated before the sensor leaves the factory.

Description

Technical Field

[0001] This invention relates to the field of optical sensor detection technology, and in particular to a method, apparatus, equipment and medium for calibrating the detection range of an optical sensor. Background Technology

[0002] With the continuous advancement of technology, the application scope of optical sensors will be further expanded. The range adjustment capability of optical sensors is a key factor in improving their flexibility and effectiveness in various applications, enabling sensors to better adapt to changing measurement environments and needs.

[0003] Changing the measurement range of traditional optical sensors typically involves adjustments to the mechanical structure to ensure a proper relationship between the optical path and the measurement range, thereby providing accurate measurement results. In laser ranging, the alignment of the transmitting and receiving optics needs to be adjusted to change the measurement range, while in fiber optic sensing, the fiber optic cabling needs to be adjusted or special fiber Bragg gratings need to be used to change the sensor's response range. However, mechanical adjustments increase system complexity and cost. Therefore, a non-mechanical, more flexible, and cost-effective solution is lacking. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a method for calibrating the detection range of an optical sensor, to solve the technical problem that mechanical adjustment in the prior art increases the complexity and cost of the detection range calibration system. The method includes:

[0005] Construct the spectral calibration curve of the optical sensor, determine the light intensity of the light source based on the spectral calibration curve, and use the light intensity that remains unchanged when the light beam emitted by the light source penetrates the blank sample as the initial reference light intensity.

[0006] A beam with an initial reference illumination intensity is split by a beam splitting system to generate spectral data including light signals of different wavelengths;

[0007] The spectral data is converted into an electrical signal. After preprocessing the electrical signal, a preprocessed electrical signal is generated. The response range of the optical sensor is determined by the preprocessed electrical signal, and the detection range of the optical sensor is determined by the response range.

[0008] Determine whether the detection range meets the accuracy requirements. If it does, end the calibration of the detection range. If it does not, change the light intensity of the light source by adjusting the voltage of the light source drive power supply, and recalibrate the detection range of the optical sensor.

[0009] This invention also provides a calibration device for the detection range of an optical sensor, addressing the technical problem that mechanical adjustment in the prior art increases the complexity and cost of the detection range calibration system. The device includes:

[0010] The reference light intensity determination module is used to construct the spectral calibration curve of the optical sensor. Based on the spectral calibration curve, the light intensity of the light source is determined. The light intensity in which the intensity of the light beam emitted by the light source remains unchanged when it penetrates the blank sample is used as the initial reference light intensity.

[0011] The spectrum generation module is used to split a beam with an initial reference illumination intensity through a spectral system to generate spectral data including light signals of different wavelengths;

[0012] The detection range module is used to convert spectral data into electrical signals, preprocess the electrical signals to generate preprocessed electrical signals, determine the response range of the optical sensor based on the preprocessed electrical signals, and determine the detection range of the optical sensor based on the response range.

[0013] The light intensity module is adjusted to determine whether the detection range meets the accuracy requirements. If it does, the calibration of the detection range ends. If it does not, the light intensity of the light source is changed by adjusting the voltage of the light source drive power supply, and the detection range of the optical sensor is recalibrated.

[0014] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the calibration method for any of the above-mentioned optical sensor detection ranges, thereby solving the technical problem that mechanical adjustment in the prior art increases the complexity and cost of the detection range calibration system.

[0015] This invention also provides a computer-readable storage medium storing a computer program that performs any of the above-described optical sensor detection range calibration methods, in order to solve the technical problem that mechanical adjustment in the prior art increases the complexity and cost of the detection range calibration system.

[0016] Compared with the prior art, the beneficial effects that at least one technical solution adopted in the embodiments of this specification can achieve include at least:

[0017] The embodiments of the present invention can calibrate the detection range of optical sensors, ensuring the accuracy and reliability of the actual sample of the optical sensor in the calibration of the detection range. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a calibration method for the detection range of an optical sensor provided in an embodiment of the present invention;

[0020] Figure 2 This is a structural block diagram of a computer device provided in an embodiment of the present invention;

[0021] Figure 3 This is a structural block diagram of an optical sensor detection range calibration device provided in an embodiment of the present invention. Detailed Implementation

[0022] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0023] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] In this embodiment of the invention, a method for calibrating the detection range of an optical sensor is provided, such as... Figure 1 As shown, the method includes:

[0025] Step S101: Construct the spectral calibration curve of the optical sensor, determine the light intensity of the light source based on the spectral calibration curve, and use the light intensity in which the intensity of the light beam emitted by the light source remains unchanged when it penetrates the blank sample as the initial reference light intensity.

[0026] Step S102: The beam with the initial reference illumination intensity is split by a beam splitting system to generate spectral data including light signals of different wavelengths;

[0027] Step S103: Convert the spectral data into an electrical signal, preprocess the electrical signal to generate a preprocessed electrical signal, determine the response range of the optical sensor through the preprocessed electrical signal, and determine the detection range of the optical sensor through the response range.

[0028] Step S104: Determine whether the detection range meets the accuracy requirements. If it does, end the calibration of the detection range. If it does not, change the light intensity of the light source by adjusting the voltage of the light source driving power supply, and recalibrate the detection range of the optical sensor.

[0029] Specifically, the light source should emit a beam with high spectral purity, high radiation intensity, excellent stability, and long lifespan. Choosing the right light source is crucial for ensuring the accuracy and reliability of the test results.

[0030] Specifically, blank samples are typically pure solvents or samples without the analyte. In spectroscopic detection, blank samples contain all factors that might affect the measurement, except for the analyte. By using blank samples, incident light loss caused by factors such as scattering and reflection can be corrected. Comparing the transmitted light intensity of blank samples with that of actual samples allows for a more accurate determination of the sample's absorbance.

[0031] Specifically, reference light intensity is a core concept in spectral analysis. It refers to the original light intensity emitted by the light source when there is no sample absorption. This benchmark value is crucial for subsequent calculations of sample absorption. Its stability and accuracy directly affect the reliability of sensor range calibration results. Absorbance is a physical quantity used in spectral analysis to describe the degree of light absorption by a substance; it is based on the Lambert-Beer law. Absorbance can be expressed as the base-10 logarithm of the ratio of the incident light intensity before passing through the sample to the outgoing light intensity after passing through the sample. Its mathematical expression is: Wherein, the incident light intensity I0 is the initial intensity of the light emitted by the light source, without any absorption or scattering by any substance; the outgoing light intensity I... t It is the intensity of light after it has been absorbed by a substance. Due to the absorption of light by the molecules of a substance, the intensity of the emitted light is usually less than the intensity of the incident light; absorbance A represents the degree to which light is absorbed when it passes through a substance, and is dimensionless.

[0032] The Lambert-Beer law describes the relationship between absorbance and the concentration and optical path length of a solution. Its mathematical expression is A = ε·c·l, where A is absorbance (dimensionless), ε is the molar absorptivity (MoA), an inherent property of a substance related to its molecular structure and the wavelength of light absorbed, measured in L·mol⁻¹. -1 ·cm -1 c is the solution concentration, in mol / L; l is the optical path length, which is the length of the path the light travels through the sample, in cm.

[0033] In practice, the following steps are used to split the beam with the initial reference illumination intensity using a beam splitting system, generating spectral data including light signals of different wavelengths:

[0034] A beam with an initial reference illumination intensity is passed through an entrance slit to generate a composite beam; the composite beam is converted into parallel light by a collimating lens; the parallel light is split by a grating to generate individual monochromatic beams ordered by wavelength; and spectral data including light signals of different wavelengths is generated from each monochromatic beam.

[0035] Specifically, a spectroscopic system is an optical device that typically includes one or more optical elements, such as prisms or gratings, that can decompose composite light into monochromatic light of different wavelengths, generating a spectrum. The spectrum can be continuous or discrete, depending on the characteristics of the sample and the light source. Composite light is composed of a mixture of multiple wavelengths of light.

[0036] The entrance slit restricts stray light from entering the beam splitting system, ensuring that only pure and collimated beams are introduced. The collimating lens converts the composite beam entering from the entrance slit into parallel light, optimizing the beam for beam splitting by the grating. The grating uses the principle of light diffraction to separate light signals of different wavelengths and disperse them in different directions. After beam splitting, the monochromatic beams are arranged in order of wavelength to generate a spectrum.

[0037] In practice, the following steps are used to convert spectral data into electrical signals, preprocess the electrical signals to generate preprocessed electrical signals, determine the response range of the optical sensor using the preprocessed electrical signals, and then determine the detection range of the optical sensor using the response range:

[0038] The optical sensor captures light signals of different wavelengths from spectral data using a detector and converts them into electrical signals. The converted electrical signals are then amplified using an amplifier to generate an amplified analog electrical signal. This analog signal is then converted into a digital electrical signal using an analog-to-digital converter. The digital electrical signal is preprocessed to generate a preprocessed electrical signal, which includes filtering, baseline correction, and integration. The response range of the optical sensor is determined using the preprocessed electrical signal, and the detection range of the optical sensor is determined based on its response range.

[0039] Specifically, the detector captures the spectrum separated by the spectral dispersive system, i.e., light with different wavelengths. Commonly used detectors include photomultiplier tubes, photodiodes, and charge-coupled devices (CCDs). The detector converts the captured light signal into an electrical signal. This process is based on the photoelectric effect, where photons excite electrons in the detector, causing changes in current or voltage. The converted electrical signal is amplified using an amplifier. The amplified electrical signal is an analog signal, which is then converted into a digital signal by an analog-to-digital converter (ADC). Digital signals are more suitable for computer processing and storage. Based on the specific application requirements and detection targets of the sensor, its optimal detection range is determined, and the sensor's detection range is precisely calibrated.

[0040] In practice, the response range of the optical sensor is determined by using the pre-processed electrical signal through the following steps:

[0041] The maximum and minimum values ​​of the preprocessed electrical signal are obtained; the response range of the optical sensor is determined by combining the maximum and minimum values ​​of the preprocessed electrical signal with the spectral correction curve.

[0042] In practice, the light intensity of the light source is changed by adjusting the voltage of the light source driver power supply through the following steps:

[0043] The switching state of the power supply is controlled by a PWM signal, causing the power supply to switch between high and low levels. The total time for the power supply to switch between high and low levels is taken as the power supply cycle time, and the duration of the power supply in the high-level state is taken as the pulse high-level time. The duty cycle is calculated from the pulse high-level time and the cycle time. The light intensity of the light source is adjusted by the duty cycle.

[0044] Specifically, the core of adjusting power supply power using the PWM method lies in controlling the duty cycle of the power switch. When the PWM duty cycle is large, it indicates a longer high-level duration and a higher output voltage; when the duty cycle is small, it indicates a shorter high-level duration and a lower output voltage.

[0045] In practice, the following steps are used to adjust the light intensity of the light source by adjusting the duty cycle:

[0046] The duty cycle of the PWM signal is proportional to the voltage output by the power supply.

[0047] In practice, the spectral calibration curve of the optical sensor is constructed through the following steps:

[0048] Construct a spectral correction curve that characterizes the relationship between the output of the optical sensor and the spectral data.

[0049] Specifically, a spectral calibration curve is constructed to convert the sensor's raw output into usable physical data. The calibration curve allows for the correction of the sensor's wavelength and light intensity responses. The spectral calibration curve (or standardization curve) of a spectral sensor is a mathematical model obtained through experimental measurements, describing the relationship between the sensor's output and actual spectral data. The spectral calibration curve ensures that the sensor's output data accurately reflects the true spectral information.

[0050] In this embodiment, a computer device is provided, such as... Figure 2 As shown, it includes a memory 201, a processor 202, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the calibration method for any of the above-mentioned optical sensor detection ranges.

[0051] Specifically, the computer device can be a computer terminal, a server, or a similar computing device.

[0052] In this embodiment, a computer-readable storage medium is provided, which stores a computer program that performs the calibration method for any of the above-described optical sensor detection ranges.

[0053] Specifically, computer-readable storage media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer-readable storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable storage media does not include transient media, such as modulated data signals and carrier waves.

[0054] Based on the same inventive concept, this invention also provides a calibration device for the detection range of an optical sensor, as described in the following embodiments. Since the principle of the calibration device for the detection range of an optical sensor is similar to that of the calibration method for the detection range of an optical sensor, the implementation of the calibration device for the detection range of an optical sensor can refer to the implementation of the calibration method for the detection range of an optical sensor, and will not be repeated. As used below, the terms "unit" or "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0055] Figure 3 This is a structural block diagram of a calibration device for the detection range of an optical sensor according to an embodiment of the present invention, such as... Figure 3 As shown, it includes: a reference light intensity determination module 301, a spectrum generation module 302, a detection range module 303, and a light intensity adjustment module 304. The structure will be described below.

[0056] The reference light intensity determination module 301 is used to construct the spectral correction curve of the optical sensor, determine the light intensity of the light source based on the spectral correction curve, and take the light intensity that remains unchanged when the light beam emitted by the light source penetrates the blank sample as the initial reference light intensity.

[0057] The spectrum generation module 302 is used to split a beam with an initial reference illumination intensity through a spectral system to generate spectral data including light signals of different wavelengths.

[0058] The detection range module 303 is used to convert spectral data into electrical signals, preprocess the electrical signals to generate preprocessed electrical signals, determine the response range of the optical sensor through the preprocessed electrical signals, and determine the detection range of the optical sensor through the response range.

[0059] The light intensity module 304 is adjusted to determine whether the detection range meets the accuracy requirements. If it does, the calibration of the detection range ends. If it does not, the light intensity of the light source is changed by adjusting the voltage of the light source drive power supply, and the detection range of the optical sensor is recalibrated.

[0060] In one embodiment, the reference light intensity determination module includes:

[0061] The spectral correction curve generation unit is used to construct a spectral correction curve that characterizes the relationship between the output of the optical sensor and the spectral data.

[0062] In one embodiment, the spectrum generation module includes:

[0063] A composite beam generation unit is used to generate a composite beam by passing a beam with an initial reference illumination intensity through an entrance slit.

[0064] A parallel beam conversion unit is used to convert a composite beam into parallel beams through a collimating lens;

[0065] The spectrum generation unit is used to split parallel light through a grating to generate individual monochromatic beams ordered by wavelength, and to generate spectral data including light signals of different wavelengths through each monochromatic beam.

[0066] In one embodiment, the detection range module includes:

[0067] An electrical signal conversion unit is used to capture light signals of different wavelengths in spectral data through a detector and convert the light signals into electrical signals.

[0068] The digital signal unit is used to amplify the converted electrical signal using an amplifier to generate an amplified analog electrical signal, and then convert the analog electrical signal into a digital electrical signal through an analog-to-digital converter.

[0069] The preprocessing unit is used to preprocess the digital electrical signal to generate a preprocessed electrical signal. The preprocessing includes filtering, baseline correction, and integration of the digital electrical signal.

[0070] The detection range determination unit is used to determine the response range of the optical sensor through the preprocessed electrical signal, and to determine the detection range of the optical sensor through the response range of the optical sensor.

[0071] In one embodiment, the detection range determination unit is used to obtain the maximum and minimum values ​​of the preprocessed electrical signal; and to determine the response range of the optical sensor by using the maximum and minimum values ​​of the preprocessed electrical signal and combining them with the spectral correction curve.

[0072] In one embodiment, adjusting the light intensity module includes:

[0073] The level switching unit is used to control the switching state of the power supply using PWM signals, so that the power supply switches between high and low levels.

[0074] The duty cycle calculation unit uses the total time for the power supply to switch between high and low levels as the power supply cycle time, and the duration of the power supply in the high-level state as the pulse high-level time. The duty cycle is then calculated using the pulse high-level time and the cycle time.

[0075] The light intensity adjustment unit is used to adjust the light intensity of the light source by adjusting the duty cycle.

[0076] In one embodiment, the light intensity adjustment unit is used to adjust the duty cycle of the PWM signal in a manner proportional to the voltage output by the power supply.

[0077] The embodiments of the present invention achieve the following technical effects:

[0078] The calibration method of this invention adjusts the output power of the light source electronically, thereby changing the light intensity and affecting the measurement range of the sensor. This avoids direct intervention in the physical structure of the optical sensor. Its advantage lies in providing non-contact range adjustment and control, while also featuring fast response and high precision. The calibration method of this invention is novel and reasonable in design, enabling range calibration of optical sensors before they leave the factory. It provides a new technical approach for adjusting the range of optical sensors and has the potential to simplify the design of optical sensors and improve their performance and application range.

[0079] Obviously, those skilled in the art should understand that the modules or steps of the above-described embodiments of the present invention can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented here, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the embodiments of the present invention are not limited to any particular hardware and software combination.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of calibrating the detection range of an optical sensor, characterized in that, The method comprises the following steps: Constructing a spectral correction curve of an optical sensor, determining the illumination intensity of a light source according to the spectral correction curve, and taking the illumination intensity of the light beam emitted by the light source as an initial reference illumination intensity when the light beam penetrates through a blank sample without changing the intensity; Splitting the light beam with the initial reference illumination intensity through a light splitting system to generate spectral data including light signals of different wavelengths; Converting the spectral data into an electrical signal, generating a pre-processed electrical signal after pre-processing the electrical signal, determining a response range of the optical sensor through the pre-processed electrical signal, and determining a detection range of the optical sensor through the response range; Determining whether the detection range meets the accuracy requirement, and if it does, ending the calibration of the detection range, and if it does not, adjusting the voltage of the light source driving power supply to change the illumination intensity of the light source, and recalibrating the detection range of the optical sensor.

2. The method of claim 1, wherein the optical sensor detection range is calibrated by: Splitting the light beam with the initial reference illumination intensity through a light splitting system to generate spectral data including light signals of different wavelengths, comprising: Passing the light beam with the initial reference illumination intensity through an entrance slit to generate a composite light beam; Converting the composite light beam into parallel light through a collimating mirror; Splitting the parallel light through a grating to generate each monochromatic light beam sorted according to wavelength order, and generating spectral data including light signals of different wavelengths through each monochromatic light beam.

3. The method of claim 1, wherein the optical sensor detection range is calibrated by: Converting the spectral data into an electrical signal, generating a pre-processed electrical signal after pre-processing the electrical signal, determining a response range of the optical sensor through the pre-processed electrical signal, and determining a detection range of the optical sensor through the response range, comprising: Capturing the light signals of different wavelengths in the spectral data through a detector, and converting the light signals into an electrical signal; Amplifying the converted electrical signal through an amplifier to generate an amplified analog electrical signal, and converting the analog electrical signal into a digital electrical signal through an analog / digital converter; Pre-processing the digital electrical signal to generate a pre-processed electrical signal, wherein the pre-processing includes filtering, baseline correction, and integration of the digital electrical signal; Determining a response range of the optical sensor through the pre-processed electrical signal, and determining a detection range of the optical sensor through the response range of the optical sensor.

4. The method of claim 3, wherein the step of calibrating the optical sensor detection range is performed by: Determining a response range of the optical sensor through the pre-processed electrical signal, comprising: Obtaining the maximum value and the minimum value of the pre-processed electrical signal; Determining the response range of the optical sensor through the maximum value of the pre-processed electrical signal, the minimum value of the pre-processed electrical signal, and in combination with the spectral correction curve.

5. The method of claim 1, wherein the optical sensor detection range is calibrated by: Adjusting the voltage of the light source driving power supply to change the illumination intensity of the light source, comprising: Controlling the switching state of the power supply through a PWM signal to make the power supply switch between high level and low level; The total time of switching the power supply between the high level and the low level is taken as a cycle time of the power supply, the time of the power supply lasting in the high level is taken as a pulse high level time, and a duty cycle is calculated by the pulse high level time and the cycle time, wherein the Adjusting the illumination intensity of the light source through the duty cycle.

6. The method of claim 5, wherein the step of calibrating the optical sensor detection range is performed by: Adjusting the illumination intensity of the light source through the duty cycle, comprising: The duty cycle of the PWM signal is proportional to the voltage output by the power supply.

7. The method of calibrating the detection range of an optical sensor according to any one of claims 1 to 6, wherein The method comprises the following steps: The method comprises the following steps:

8. An apparatus for calibrating the detection range of an optical sensor, characterized in that The method comprises the following steps: The method comprises the following steps: The method comprises the following steps: The method comprises the following steps: The method comprises the following steps:

9. A computer device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The method comprises the following steps:

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