CN116807468A - Blood oxygen detection method based on wide-spectrum synchronous excitation light source and multispectral image - Google Patents
Blood oxygen detection method based on wide-spectrum synchronous excitation light source and multispectral image Download PDFInfo
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Abstract
The invention belongs to the technical field of spectrum component detection, and relates to a blood oxygen detection method based on a broad spectrum synchronous excitation light source and multispectral images, which comprises the following steps: step S1: a spectral band separation algorithm; selecting a narrower working wave band in the whole light source spectrum range according to the spectrum characteristics of blood oxygen, skin and ambient light, and extracting multispectral images aiming at the blood oxygen sensitive spectrum, skin type sensitive spectrum and skin color sensitive spectrum in the same wave band; step S2: removing a skin-color interference algorithm; identifying skin colors based on band images with the wavelength range of 400-700 nm extracted by a spectral band separation algorithm, and correcting errors of skin color differences on blood oxygen detection; step S3: synchronously extracting PPG signals and calculating a blood oxygen algorithm; and obtaining images of different characteristic wave bands from the same multispectral image based on a spectral band separation algorithm, extracting corresponding PPG signals from the images of different wave bands, and calculating blood oxygen values. The invention has the advantages that: the specific system has high integration level, small volume and strong portability.
Description
Technical Field
The invention relates to a noninvasive blood oxygen detection method, in particular to a blood oxygen detection method based on a wide-spectrum synchronous excitation light source and multispectral images.
Background
With the continuous development of society and economy, people pay more and more attention to the physical state of individuals, wherein the blood oxygen saturation is an important parameter index, and the blood oxygen saturation is mainly used for reflecting the oxygen supply capacity of organisms. There are some methods for noninvasively monitoring the real-time blood oxygen state of human body based on optical detection at present. As in the document of Chinese patent publication No. CN 113598761A, a CCD-based dual-wavelength infrared blood oxygen detection system is disclosed, which adopts a near infrared point light source to start two wavelength light sources in a time-sharing way, a CCD sensor collects image information, and a PPG signal is extracted to calculate a blood oxygen value; the Chinese patent publication number is as follows: in the CN 11355861A literature, the method for detecting the double-wavelength photoacoustic blood oxygen adopts two pulse laser sources with different wavelengths to trigger alternately, so as to obtain ultrasonic waves; analyzing the ultrasonic wave to obtain an oxygen value; as in the chinese patent publication No. CN 114073520A, the detecting device for blood oxygen based on green light, and the blood oxygen detecting method and medium thereof, the detecting device includes a PPG sensor, the PPG sensor includes at least one green light source, one red light source, at least one infrared light source and at least one photoelectric sensor, the invention judges PPG signal quality by adding green light signal, and improves accuracy of blood oxygen detection; as in the document of chinese patent CN 114847944A, a hyperspectral cerebral blood oxygen detection system, the system controller, the light source detector, the filter disc, the data acquisition and data processing module, based on a plurality of filters, can realize the extraction and application of light in different wave bands; selecting a characteristic narrow-band filter as a light splitting element in a literature of a research on a multi-spectral imaging in-vivo tissue detection method, constructing a multi-spectral imaging system, and calculating a blood oxygen value by combining wiener estimation and a spectrum second derivative method; as in the document of chinese patent CN 115089171A, an improvement in accuracy of blood oxygen detection results of dark skin color people is achieved, in which an oximeter MCU is used to receive RGB values of skin colors detected by a color sensor, and whether to use a first light-emitting tube (normal power) or a second light-emitting tube (increased power) is determined to detect blood oxygen by the detected RGB values; the literature of IPPG-based non-contact blood oxygen saturation detection technology proposes a non-contact blood oxygen calculating mode, which mainly comprises the steps of video recording of a human face, image extraction of physiological information, channel separation to obtain R and B channel data, filtering transformation and the like, and blood oxygen value calculation.
Two broad categories can be distinguished based on the above patents: one is of the time-sharing detection type, one is of the multispectral and hyperspectral type, the time-sharing detection type comprising the following patents: CN 113598761A is a dual-wavelength infrared blood oxygen detection system based on CCD, a detection method of CN 11355861A dual-wavelength photoacoustic blood oxygen, etc., which has the advantages of small volume and low cost, but the time-sharing detection is easy to receive the interference of electromagnetic wave in the environment, and the detection precision is lower; multispectral and hyperspectral type brain blood oxygen detection system comprises a hyperspectral brain blood oxygen detection system of patent CN 114847944A, and papers (research based on multispectral imaging in-vivo tissue detection method) and the like, and have the advantages of high detection precision, good instantaneity and the like, but have the problems of large volume, complex structure, high cost, poor adaptability of different skin types and skin colors and the like.
What is needed is a blood oxygen detection system based on a wide-spectrum synchronous excitation light source and multispectral images, so as to solve the problem that the time-sharing detection type precision is low; the multispectral and hyperspectral blood oxygen detection equipment has the problems of large volume, complex detection system, high cost, poor portability and the like.
Disclosure of Invention
In view of the above problems, the invention provides a blood oxygen detection system and a blood oxygen detection method based on a wide-spectrum synchronous excitation light source and multispectral image, which realize synchronous PPG signal extraction and blood oxygen calculation, and solve the problems of time-sharing acquisition signal interference and the like; the wide-spectrum synchronous excitation light source is adopted, so that the method has the advantages of wide coverage spectrum range, large information quantity, strong applicability and the like, and realizes extraction of wave band images corresponding to different wave bands based on the same multispectral image and synchronous extraction of PPG signals to calculate blood oxygen values; meanwhile, the blood oxygen detection error caused by the skin-color difference is corrected; and the blood oxygen detection precision is improved. To overcome the deficiencies of the prior art described above.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a blood oxygen detection method based on a wide-spectrum synchronous excitation light source and multispectral images is characterized by comprising the following steps of: the method comprises the following steps:
step S1: a spectral band separation algorithm;
selecting a narrower working wave band in the whole light source spectrum range according to the spectrum characteristics of blood oxygen, skin and ambient light, and extracting multispectral images aiming at the blood oxygen sensitive spectrum, skin type sensitive spectrum and skin color sensitive spectrum in the same wave band;
step S2: removing a skin-color interference algorithm;
identifying skin colors based on band images with the wavelength range of 400-700 nm extracted by a spectral band separation algorithm, and correcting errors of skin color differences on blood oxygen detection;
step S3: synchronously extracting PPG signals and calculating a blood oxygen algorithm;
and obtaining images of different characteristic wave bands from the same multispectral image based on a spectral band separation algorithm, extracting corresponding PPG signals from the images of different wave bands, and calculating blood oxygen values.
Preferably, the spectrum band separation algorithm comprises the following steps:
step S11: pre-storing spectral information of common blood oxygen and skin characteristic wave bands as reference spectral information, and recording as light_spec;
step S12: starting a wide-spectrum synchronous excitation light source, acquiring a multispectral image of a fingertip part by using a multispectral imaging chip, performing background removal and noise removal pretreatment on the acquired multispectral image, taking the pretreated multispectral image as an original image, and recording the original image as an original_img;
step S13: based on the superposition of the image elements of each wave band in the original_img obtained in the step S12, the pixel expression of the multispectral image is as follows;
x(i,j)=∑A×λ(i,j) （1）
wherein: x (i, j) is the pixel data of original_img obtained in step S12; λ (i, j) is the pixel information of each band image; a is the ratio of the pixel information of each band image in the original_img pixel data, i.e. Σa=a 1 +A 2 +A 3 +...=1；
Step S14: calculating the distance between the original_img pixel data and the fitting pixel data according to formula (2), when the distance is less than 10 -4 Outputting A when the first time is over;
dis = ||x(i,j)-A×λ(i,j)|| （2）
step S15: based on the step S13, solving the duty ratio of the image element information of different wave bands in the multispectral image, and combining the spectrum information light_spec of different wave bands in the step S11, and obtaining the spectrums corresponding to the wave bands according to the formula (3);
spinv =light_spec × A （3）
step S16: based on the spectrum information obtained in the step S15, selecting a required wave band for summation, and obtaining a multispectral image of a corresponding wave band;
img = ∑spinv（λ）。 （4）
as a preferred aspect of the present invention, the algorithm for removing skin-tone interference includes the steps of:
step S21: extracting a wave band image corresponding to the wavelength of 400-700 nm according to a spectral band separation algorithm;
step S22: obtaining a corresponding spectrum curve according to a formula (3);
step S23: pre-storing and setting a spectrum curve corresponding to yellow skin as a skin color standard curve, and recording as spec; calculating the deviation between the spectrum curve obtained in the step S22 and the standard curve; calculating deviation, which is recorded as bias;
bias = 1/n×∑(spec - spinv) 2 （5）
wherein: n is the number of spectral range intervals.
Preferably, the method for synchronously extracting the PPG signal and calculating the blood oxygen algorithm comprises the following steps:
step S31: obtaining images of a visible light wave band and near infrared 940nm based on a spectral band separation algorithm, respectively extracting corresponding PPG signals based on the images of the visible light wave band and the near infrared 940nm, and simultaneously extracting a direct current signal (DC) and an alternating current signal (AC) and calculating the amplitudes of the two signals;
step S32: obtaining alternating current signal amplitude (I) of PPG signals in different wave bands according to a formula (6) AC ) And DC signal amplitude (I DC ) Is a ratio of (2);
A light =I AC /I DC （6）
wherein: i AC Is the amplitude of the ac signal in the PPG signal; i DC Is the amplitude of the direct current signal in the PPG signal; light is the ratio of the alternating current signal amplitude to the direct current signal amplitude in the PPG signal corresponding to the same band;
step S33: calculating according to a formula (6) to obtain light corresponding to each wave band, and calculating according to a formula (7) to obtain an R value;
R = Alight 1 /Alight 2 （7）
step S34: correcting the deviation of skin complexion according to the formula (8), then:
R xz = R × bias （8）
wherein: r is R xz The R value is subjected to skin color influence correction, and bias is the deviation between the skin color spectrum of the skin to be detected and the skin color spectrum of the standard skin;
step S35: calibrating and correcting blood oxygen values affected by skin color difference according to a formula (9):
SpO 2 = C × R xz 2 + D × R xz + E （9）
wherein: sp0 2 Is the blood oxygen saturation value, C, D and E are respectively the calibration coefficients, R xz Is the R value after the skin color is modified.
Preferably, the broad spectrum synchronous excitation light source is used for emitting light covering continuous spectrum of blood oxygen and skin sensitive spectrum, and the spectrum range is 350nm-950nm.
Preferably, the multispectral imaging chip is used for collecting multispectral images of the fingertip part.
The invention further aims to provide a blood oxygen detection system based on the wide-spectrum synchronous excitation light source and the multispectral image, which comprises the wide-spectrum synchronous excitation light source, the multispectral imaging chip and the algorithm processing module; the wide-spectrum synchronous excitation light source is used for emitting light with continuous spectrum; the multispectral imaging chip collects multispectral images of the fingertip part; the algorithm processing module comprises: the system comprises a spectrum band separation algorithm module, a skin-color interference removal algorithm module, a synchronous PPG signal extraction and blood oxygen calculation algorithm module; the spectrum band separation algorithm module performs selection of a narrower working band in the whole light source spectrum range according to the spectrum characteristics of blood oxygen, skin and ambient light, extracts multispectral images of different bands of blood oxygen sensitive spectrum band, skin type sensitive spectrum band and skin color sensitive spectrum band, and lays a foundation for eliminating various interferences and calculating accurate blood oxygen values; the skin-tone removal skin-tone interference algorithm module is used for identifying skin-tone based on the visible light wave band image extracted by the spectral band separation algorithm module, and correcting errors of skin-tone deviation on blood oxygen detection; and the synchronous PPG signal extraction and blood oxygen calculation algorithm module is used for extracting PPG signals corresponding to different wave bands at the same time on the same multispectral image and calculating blood oxygen values.
Preferably, the broad spectrum synchronous excitation light source is used for emitting light covering continuous spectrum of blood oxygen and skin sensitive spectrum, and the spectrum range is 350nm-950nm.
The invention has the advantages and positive effects that: the problem of time-sharing triggering detection of the blood oxygen by two light sources with different wavelengths in the prior art is solved by the wide-spectrum synchronous excitation light source, the blood oxygen detection time is shortened, the detection error is reduced, and the measurement accuracy is improved; meanwhile, a mode of combining a wide-spectrum synchronous excitation light source with a spectrum separation algorithm is adopted, the selection of a narrower working wave band and the extraction of multispectral images aiming at different wave bands such as a blood oxygen sensitive spectrum band, a skin color sensitive spectrum band and a skin color sensitive spectrum band are realized in the whole light source spectrum range according to the spectral characteristics of blood oxygen, skin, ambient light and the like, the skin color identification is realized by extracting the visible light wave band image, the error of the skin color difference in blood oxygen detection is corrected, the detection of blood oxygen is carried out by extracting the visible light wave band and the near infrared wave band image, the complexity of a detection system is reduced, and the volume of a detection device is reduced; the PPG signal is synchronously extracted and the blood oxygen algorithm is calculated, so that the error influence caused by different blood states at different moments is avoided, and the accuracy of blood oxygen detection is improved; therefore, the invention synchronously extracts PPG signals and calculates blood oxygen based on more spectral bands and large information quantity generated by the wide-band synchronous excitation light source, thereby improving the accuracy of blood oxygen detection; meanwhile, the system has high integration level, small volume and strong portability.
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Other objects and attainments together with a more complete understanding of the invention will become apparent and appreciated by referring to the following description taken in conjunction with the accompanying drawings. In the drawings:
FIG. 1 is a schematic diagram of a blood oxygen detection system based on a broad spectrum synchronous excitation light source and multispectral images;
FIG. 2 is a flow chart of a spectral band separation algorithm;
FIG. 3 is a flowchart of an algorithm for removing skin disturbances;
FIG. 4 is a flow chart of a blood oxygen detection system based on a broad spectrum synchronous excitation light source and multispectral image;
description of the drawings: the finger to be detected 1, a wide-spectrum synchronous excitation light source 2, an integrated module 3, a circuit interface 4, a multispectral imaging chip 5 and red blood cells 6.
Description of the embodiments
In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.
Example 1
Fig. 1 shows a schematic overall structure according to an embodiment of the present invention.
A blood oxygen detection system based on a wide-spectrum synchronous excitation light source and multispectral images, a hardware part and an algorithm processing module, wherein the hardware part mainly comprises: a wide-spectrum synchronous excitation light source 1 and a multispectral imaging chip 5; the algorithm processing module is integrated in the integrated module 3, and a circuit interface 4 is installed on one side of the integrated module 3, wherein the algorithm processing module comprises: the system comprises a spectrum band separation algorithm module, a skin-color interference removal algorithm module, a synchronous PPG signal extraction and blood oxygen calculation algorithm module; the broad spectrum synchronous excitation light source 2 can emit light of continuous wave bands covering blood oxygen and skin sensitive spectrum; the multispectral imaging chip 5 is mainly used for multispectral image acquisition of the fingertip part irradiated by the wide-spectrum synchronous excitation light source 2 by using the multispectral imaging chip 5, the working spectrum can cover the blood oxygen and skin sensitive spectrum, the spectrum range is 350-950 nm, and the exposure time and the time sequence are recorded; the multispectral imaging chip 2 adopted in the embodiment is a multispectral imaging chip and a color imaging method, wherein the patent number of the multispectral imaging chip is 202010211115.0, and the patent name of the multispectral imaging chip is that color imaging can be achieved.
Example 2
As shown in fig. 1-4, this example specifically includes the steps of:
step S1, pressing the fingertips of the finger 1 to be detected on an integrated module 3 provided with a wide-spectrum synchronous excitation light source 2 and a multispectral imaging chip 5 for red blood cells 6 in the finger 1 to be detected;
step S2: the wide-spectrum synchronous excitation light source 2 is started, and light is vertically irradiated to the fingertip part of the finger 1 to be detected;
step S3: the multispectral imaging chip 5 starts to collect multispectral images of the fingertip part of the finger 1 to be detected, and simultaneously saves exposure time and time sequence;
step S4: the multispectral imaging chip 5 finishes acquisition and simultaneously controls the wide-spectrum synchronous excitation light source 2 to be closed;
step S5: the spectrum band separation algorithm pre-stores the spectrum information of different wave bands used, and marks the spectrum information as: light_spec;
step S6: preprocessing a multispectral image acquired by the multispectral imaging chip 5, wherein the preprocessed image is used as original data;
step S7: the spectrum band separation algorithm calculates the occupation ratio of the corresponding pixels of the visible light wave band on the multispectral image acquired by the multispectral imaging chip 5 according to the formula (1) to obtain the occupation ratio of the pixels of the visible light wave band image in the original image pixels;
x(i,j)=∑A×λ(i,j) （1）
wherein: x (i, j) is the pixel data of the original image obtained in S6; λ (i, j) is the pixel information of each band image; a is the duty ratio of the pixel information of each band image in the original image, i.e. Σa=a 1 +A 2 +A 3 +...=1；
Step S8: setting an initial value of A, calculating by using an iterative calculation method, and when the distance between the pixels of the original image and the fitted pixels is smaller than 10 -4 Outputting a corresponding duty ratio A;
dis = ||x(i,j)-A×λ(i,j)|| （2）
step S9: according to the corresponding optimal pixel duty ratio obtained in the step S8, corresponding visible spectrum information can be obtained;
spinv =light_spec × A （3）
step S10: based on the visible spectrum of step S9, the spectrum is compared with the set standard spectrum, denoted spec, and the bias value bias is calculated according to formula (5):
bias = 1/n×∑(spec - spinv) 2 （5）
step S11: the spectrum band separation algorithm calculates the spectrum of the visible light wave band and the near infrared 940nm wavelength according to the formula (1), the formula (2) and the formula (3);
step S12: according to the spectrum information of the visible light wave band and the near infrared 940nm wavelength calculated in the step S11, calculating a corresponding multispectral image according to a formula (4);
img = ∑spinv（λ） （4）
step S13: extracting a PPG signal based on the visible light image obtained in the step S12 and the image corresponding to the near infrared 940nm wavelength; according to formula (6), calculating the alignment corresponding to the visible light band 1 And an align corresponding to a near infrared 940nm wavelength 2 ，
A light =I AC /I DC （6）
Step S14: calculating an R coefficient according to the weight calculated in the step S13 and the formula (7);
R = Alight 1 /Alight 2 （7）
step S15: according to the skin-tone deviation bias calculated in the step S10, the skin-tone deviation is corrected, and the corrected R is obtained according to the formula (8) xz ；
R xz = R × bias （8）
Step S16: calculating the blood oxygen value under the skin color according to the formula (9):
SpO 2 = C × R xz 2 + D × R xz + E （9）
wherein: spO (SpO) 2 Is the blood oxygen saturation value, C, D and E are respectively the calibration coefficients, R xz Is the R value after the skin color is modified.
In summary, the blood oxygen detection system based on the wide-spectrum synchronous excitation light source and the multispectral image realizes that the mode of measuring blood oxygen by the wide-spectrum synchronous excitation light source replaces the existing dual-wavelength dual-light source alternative scintillation measurement mode; the method widens the wave band range, enriches the spectrum information, reduces the measurement error, shortens the time of image acquisition, avoids the errors of baseline drift, potential electric interference and the like, and improves the accuracy of blood oxygen detection.
The foregoing is merely illustrative embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think about variations or substitutions within the technical scope of the present invention, and the invention should be covered. Therefore, the protection scope of the invention is subject to the protection scope of the claims.
Claims (8)
1. A blood oxygen detection method based on a wide-spectrum synchronous excitation light source and multispectral images is characterized by comprising the following steps of: the method comprises the following steps:
step S1: a spectral band separation algorithm;
selecting a narrower working wave band in the whole light source spectrum range according to the spectrum characteristics of blood oxygen, skin and ambient light, and extracting multispectral images aiming at the blood oxygen sensitive spectrum, skin type sensitive spectrum and skin color sensitive spectrum in the same wave band;
step S2: removing a skin-color interference algorithm;
identifying skin colors based on band images with the wavelength range of 400-700 nm extracted by a spectral band separation algorithm, and correcting errors of skin color differences on blood oxygen detection;
step S3: synchronously extracting PPG signals and calculating a blood oxygen algorithm;
and obtaining images of different characteristic wave bands from the same multispectral image based on a spectral band separation algorithm, extracting corresponding PPG signals from the images of different wave bands, and calculating blood oxygen values.
2. The blood oxygen detection method based on the wide-spectrum synchronous excitation light source and the multispectral image according to claim 1, which is characterized in that: the spectral band separation algorithm comprises the following steps:
step S11: pre-storing spectral information of common blood oxygen and skin characteristic wave bands as reference spectral information, and recording as light_spec;
step S12: starting a wide-spectrum synchronous excitation light source, acquiring a multispectral image of a fingertip part by using a multispectral imaging chip, performing background removal and noise removal pretreatment on the acquired multispectral image, taking the pretreated multispectral image as an original image, and recording the original image as an original_img;
step S13: based on the superposition of the image elements of each wave band in the original_img obtained in the step S12, the pixel expression of the multispectral image is as follows;
x(i,j)=∑A×λ(i,j) （1）
wherein: x (i, j) is the pixel data of original_img obtained in step S12; λ (i, j) is the pixel information of each band image; a is the ratio of the pixel information of each band image in the original_img pixel data, i.e. Σa=a 1 +A 2 +A 3 +...=1；
Step S14: calculating the distance between the original_img pixel data and the fitting pixel data according to formula (2), when the distance is less than 10 -4 Outputting A when the first time is over;
dis = ||x(i,j)-A×λ(i,j)|| （2）
step S15: based on the step S13, solving the duty ratio of the image element information of different wave bands in the multispectral image, and combining the spectrum information light_spec of different wave bands in the step S11, and obtaining the spectrums corresponding to the wave bands according to the formula (3);
spinv =light_spec × A （3）
step S16: based on the spectrum information obtained in the step S15, selecting a required wave band for summation, and obtaining a multispectral image of a corresponding wave band;
img = ∑spinv（λ） （4）。
3. the blood oxygen detection method based on the wide-spectrum synchronous excitation light source and the multispectral image according to claim 1, which is characterized in that: the algorithm for removing the skin-color interference comprises the following steps:
step S21: extracting a wave band image corresponding to the wavelength of 400-700 nm according to a spectral band separation algorithm;
step S22: obtaining a corresponding spectrum curve according to a formula (3);
step S23: pre-storing and setting a spectrum curve corresponding to yellow skin as a skin color standard curve, and recording as spec; calculating the deviation between the spectrum curve obtained in the step S22 and the standard curve; calculating deviation, which is recorded as bias;
bias = 1/n×∑(spec - spinv) 2 （5）
wherein: n is the number of spectral range intervals.
4. The blood oxygen detection method based on the wide-spectrum synchronous excitation light source and the multispectral image according to claim 1, which is characterized in that: the synchronous PPG signal extraction and blood oxygen calculation algorithm comprises the following steps:
step S31: obtaining images of visible light wave bands and near infrared 940nm based on a spectral band separation algorithm, respectively extracting corresponding PPG signals based on the images of the visible light wave bands and the near infrared 940nm, and simultaneously extracting direct current signals and alternating current signals and calculating the amplitudes of the two signals;
step S32: obtaining the ratio of the alternating current signal amplitude and the direct current signal amplitude of the PPG signals in different wave bands according to a formula (6);
A light =I AC /I DC （6）
wherein: i AC Is the amplitude of the ac signal in the PPG signal; i DC Is the amplitude of the direct current signal in the PPG signal; light is the ratio of the alternating current signal amplitude to the direct current signal amplitude in the PPG signal corresponding to the same band;
step S33: calculating according to a formula (6) to obtain light corresponding to each wave band, and calculating according to a formula (7) to obtain an R value;
R = Alight 1 /Alight 2 （7）
step S34: correcting the deviation of skin complexion according to the formula (8), then:
R xz = R × bias （8）
wherein: r is R xz The R value is subjected to skin color influence correction, and bias is the deviation between the skin color spectrum of the skin to be detected and the skin color spectrum of the standard skin;
step S35: calibrating and correcting blood oxygen values affected by skin color difference according to a formula (9):
SpO 2 = C ×R xz 2 + D ×R xz + E （9）
wherein: spO (SpO) 2 Is the blood oxygen saturation value, C, D and E are respectively the calibration coefficients, R xz Is the R value after the skin color is modified.
5. The blood oxygen detection method based on the wide-spectrum synchronous excitation light source and the multispectral image according to claim 2, which is characterized in that: the broad spectrum synchronous excitation light source is used for emitting light of a continuous spectrum covering blood oxygen and skin sensitive spectrum, and the spectrum range is 350nm-950nm.
6. The blood oxygen detection method based on the wide-spectrum synchronous excitation light source and the multispectral image according to claim 2, which is characterized in that: the multispectral imaging chip is used for collecting multispectral images of the fingertip parts.
7. A blood oxygen detecting system based on a wide-spectrum synchronous excitation light source and multispectral images is characterized in that: the device comprises a wide-spectrum synchronous excitation light source, a multispectral imaging chip and an algorithm processing module; the wide-spectrum synchronous excitation light source is used for emitting light with continuous spectrum; the multispectral imaging chip collects multispectral images of the fingertip part; the algorithm processing module comprises: the system comprises a spectrum band separation algorithm module, a skin-color interference removal algorithm module, a synchronous PPG signal extraction and blood oxygen calculation algorithm module; the spectrum band separation algorithm module performs selection of a narrower working wave band in the whole light source spectrum range according to the spectrum characteristics of blood oxygen, skin and ambient light, and extracts multispectral images of different wave bands of blood oxygen sensitive spectrum band, skin sensitive spectrum band and skin color sensitive spectrum band; the skin-tone removal skin-tone interference algorithm module is used for identifying skin-tone based on the visible light wave band image extracted by the spectral band separation algorithm module, and correcting errors of skin-tone deviation on blood oxygen detection; and the synchronous PPG signal extraction and blood oxygen calculation algorithm module is used for extracting PPG signals corresponding to different wave bands at the same time on the same multispectral image and calculating blood oxygen values.
8. The blood oxygen detection system based on the broad spectrum synchronous excitation light source and the multispectral image according to claim 7, wherein the blood oxygen detection system is characterized in that: the broad spectrum synchronous excitation light source is used for emitting light of a continuous spectrum covering blood oxygen and skin sensitive spectrum, and the spectrum range is 350nm-950nm.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
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