CN116570278A

CN116570278A - Jaundice instrument based on programmable digital LED microarray and measuring method thereof

Info

Publication number: CN116570278A
Application number: CN202310640678.5A
Authority: CN
Inventors: 李俊吉; 刘晓东; 李运华; 吴一凡
Original assignee: Nanjing University Of Science And Technology Consulting Development Co ltd
Current assignee: Nanjing University Of Science And Technology Consulting Development Co ltd
Priority date: 2023-06-01
Filing date: 2023-06-01
Publication date: 2023-08-11

Abstract

The invention discloses a jaundice instrument based on a programmable digital LED microarray and a measuring method thereof, wherein the jaundice instrument comprises: the system comprises a digital LED micro array, a photoelectric conversion module and a main control chip. The measurement includes the following steps: the light-emitting units in the digital LED microarray are controlled by a preset program to sequentially emit light in a combined mode, and the light beams are collected by a light trapping window after being reflected and absorbed by skin tissues and are transmitted to a photoelectric conversion module through optical fibers to be converted into digital electric signals; the measurement signals obtained each time contain multi-dimensional information such as epidermis thickness, pigment distribution, blood vessel depth and the like, and accurate percutaneous jaundice values are obtained by analyzing and calculating the differentiated measurement results. The invention is based on a space-time controllable excitation mode, and can solve the problem of inaccurate measurement caused by systematic errors such as ambient light brightness, interference molecular distribution, individual skin differentiation and the like in the prior art.

Description

Jaundice instrument based on programmable digital LED microarray and measuring method thereof

Technical Field

The invention relates to the technical field of jaundice instruments, in particular to a programmable digital LED microarray-based jaundice instrument and a measuring method thereof.

Background

The traditional method for measuring jaundice is to measure the bilirubin content in a blood sample of a patient, and the method needs processes of blood drawing, laboratory operation and the like, which are troublesome and time-consuming. The jaundice degree of a patient can be rapidly and accurately measured by using the optical principle through a non-invasive mode, so that the pain and discomfort of the patient are relieved. The jaundice instrument is mainly applied to neonatal jaundice screening. Neonatal jaundice is a common disease, but if not diagnosed and treated in time, can result in serious neurological damage. The jaundice instrument can rapidly and accurately measure the degree of neonatal jaundice, help doctors to take treatment measures in time, and protect the health of infants. In addition, the percutaneous jaundice instrument can also assist liver function examination and bile duct disease diagnosis, and is also a rapid detection device for researching drug liver metabolism.

Although jaundice has many advantages, there are also problems and bottlenecks, the most important of which is accuracy. Jaundice accuracy is affected by a number of factors, including light interference, skin tone, trauma, medications, and the like. For example, the intensity, color, direction, etc. of ambient light may affect the measurement; local skin bruising or oedema caused by collision and differential distribution of bilirubin and interferent molecules in skin tissue structures of people with different skin colors can influence the measurement result of a jaundice instrument.

Disclosure of Invention

The invention aims to solve the technical problem of providing a jaundice instrument based on a programmable digital LED microarray and a measuring method thereof, and solves the problem of measuring accuracy caused by system errors such as ambient light interference, uneven distribution of interfering molecules, individual differentiation of sampled skin and the like in the prior art based on a space-time controllable excitation mode.

In order to solve the technical problems, the invention provides a jaundice instrument based on a programmable digital LED microarray, which mainly comprises: the system comprises a digital LED microarray, a photoelectric conversion module and a main control chip; the main control chip controls and drives a plurality of LED light emitting units in the digital LED microarray to emit light according to preset combination in a required period, and after each emitted light beam is absorbed by skin tissue, the light beam is transmitted to the photoelectric conversion module by the optical fiber after the trapping window to become a digitized electric signal and is transmitted to the main control chip for storage.

Preferably, the digital LED microarray includes an LED excitation light array and a light trapping window; the LED excitation light array is used as a signal source, and each LED unit in the array has at least one parameter different in terms of two parameters of the light emitting wavelength and the spatial position relative to the light trapping window.

Preferably, each LED unit in the array is a single-color LED with a central light emitting wavelength of about 460nm, a single-color LED with a wavelength of 550nm, or a combination of broad-spectrum LEDs and 460nm and 550nm filter films.

Preferably, the LED units are separated by a dark light absorbing material.

Preferably, for each LED unit in the LED microarray, any one or more of the units can be programmed to emit light at the desired time.

Preferably, by controlling monochromatic excitation light at different positions perpendicular to the direction of the light trapping window, optical path calibration and calculation of the subcutaneous deep and shallow jaundice light concentration difference can be performed; the uniformity of light absorption of the epidermis, the shallow skin portion and the deep skin portion is judged by controlling monochromatic excitation light at different positions parallel to the light trapping window direction, and an effective detection selective area is determined.

Preferably, the LED units are distributed concentrically (parallel) and axially (perpendicular) around the circular light trapping window.

Correspondingly, the measuring method of the jaundice instrument based on the programmable digital LED microarray comprises the following steps of:

step 1, a plurality of LED units in a digital LED microarray are controlled by a main control chip to respectively emit excitation light combinations composed of 460nm and 550nm monochromatic lights with different wavelengths for one time or multiple times, wherein each beam of excitation light is scattered and refracted through various tissues of the skin, part of light returns to a circular light trapping window area, and the light returns to a photoelectric conversion module through optical fibers after the light trapping window to be converted into a digital electric signal;

step 2, sequentially exciting the same-color LED units at the positions closer to and farther from the central light trapping window to obtain a group of differential light absorption values or absorption spectrums;

step 3, switching the wavelength types of the excited LED units, and obtaining another group of information sets;

and 4, each time the obtained electric signal contains information from multiple dimensions, the differentiated measured values are synthesized, and an accurate jaundice measured value is calculated.

Preferably, in step 3, LED units with the same excitation wavelength are selected to enhance the excitation light signal.

Preferably, in step 4, prior parameters such as bilirubin distribution parameter set, low beam absorption model value matrix, high beam absorption model value matrix and the like are preset, local bilirubin absorption contribution values from different skin layers are analyzed by combining multiple and multi-region long and short optical path absorption value measurement, and retrospectively accurate percutaneous jaundice measurement values are calculated.

The beneficial effects of the invention are as follows: (1) By using the programmable digital LED microarray, the jaundice instrument can judge whether the skin of a detection area has tissue differences such as chromatic aberration and edema, so that effective and accurate detection is ensured, and a reliable basis is provided for obtaining a quantized percutaneous jaundice value which can be compared transversely; (2) By using a programmable digital LED microarray and sequentially exciting LED light emitting units located at different locations, jaundice instruments can adjust the optical path difference in both physical distance and wavelength dimensions for the exclusion of interfering factors such as: obtaining accurate and pure percutaneous jaundice measurement values which have higher specific correlation with bilirubin molecule concentration in blood by errors caused by factors such as melanin, hemoglobin, collagen, shallow skin structures and the like; (3) Through the combined use of the two gain effects, the jaundice instrument can quickly construct a three-dimensional simple model of the skin area to be detected by utilizing a series of numerical sets of absorption light intensity, and further dock an experience curve or an artificial intelligence algorithm to perfect a detection model so as to obtain a real and reliable percutaneous jaundice value calculation mode; (4) By using the programmable digital LED microarray, the jaundice instrument can customize a time-resolved excitation light scheme according to different application modes, and control any plurality of LED light-emitting units in two dimensions of position and time so as to optimally match excitation conditions required by real detection; (5) Through array excitation, the same-color LED units can be simultaneously lightened, excitation light signals are greatly enhanced, and aiming at special application scenes such as dark complexion or strong ambient light interference, the jaundice instrument can provide input and output signal intensities with higher signal-to-noise ratio.

Drawings

Fig. 1 is a schematic diagram of the external structure of the jaundice apparatus according to the present invention.

Fig. 2 is a schematic diagram of an electronic module in the jaundice apparatus according to the present invention.

Fig. 3 is a schematic flow chart of the measuring principle of the jaundice instrument of the present invention.

Fig. 4 is a schematic diagram of a jaundice apparatus according to the present invention.

Fig. 5 is a detailed view of the structure of fig. 4 a in accordance with the present invention.

Fig. 6 is a schematic diagram of the principle of the present invention for judging whether skin selected area is proper.

FIG. 7 is a schematic diagram of the present invention for correcting an interferent error by optical path difference.

Detailed Description

Fig. 1 is a schematic diagram of the external structure of the jaundice apparatus according to the present invention. The device comprises a device shell 1, a detection probe 2, a mode switching key 3, a display screen 4, a switch 5 and other hardware elements.

The internal structure of the instrument is schematically shown in fig. 2, and mainly comprises a detection probe driving and light conducting module 6, a main control chip 7, a photoelectric conversion module 8, a display and driving module 9 and an external communication interface 10.

As shown in fig. 3, 4 and 5, a programmable digital LED microarray-based jaundice instrument comprising: the system comprises a digital LED microarray, a photoelectric conversion module and a main control chip; the main control chip controls and drives a plurality of LED light emitting units in the digital LED micro-array to emit light according to preset combination in a required period, and light beams emitted each time are transmitted to the photoelectric conversion module to change digital electric signals after being processed and transmitted to the main control chip for storage.

The light trapping window 102 is positioned at the center of the contact surface of the jaundice detector probe, and the LED array 101 comprises two single-color LED units capable of generating the central excitation light with the wavelength of about 460nm and 550nm, wherein the LED units are distributed in a concentric (parallel, 401) and axial (vertical, 301) direction around the circular light trapping window and are alternately arranged in one direction; and (3) performing space-time controllable on and off of specific light emitting units in the digital LED microarray through a preset program in the main control chip to obtain a series of percutaneous dual-wavelength absorption values or absorption spectrums, so as to judge the measurement reliability and calculate percutaneous jaundice measured values after correcting various errors.

step 1, an LED unit in a digital LED microarray is controlled by a main control chip to emit 460nm and 550nm monochromatic light with different wavelengths, and part of the light returns to a circular light trapping window area through various scattering and refraction and is transmitted to a photoelectric conversion module through an optical fiber after the light trapping window to be converted into a numeric electric signal;

step 2, sequentially exciting the same-color LED units at the positions closer to and farther from the central light trapping window to obtain differentiated light absorption values or absorption spectrums;

The following preparation work needs to be performed to ensure the accuracy of the measurement result and the safety of the patient before using the jaundice instrument. First, it is checked whether the jaundice instrument is intact, has sufficient power supply, and performs necessary cleaning and disinfection treatment. It is also necessary to confirm whether the patient meets the conditions for using the jaundice apparatus, for example, whether the patient has serious skin injury or wound, serious anemia or hematopathy, etc. The appropriate measurement site is then visually selected, typically on the forehead or palm of the patient.

In order to ensure the normal use of the instrument, the instrument should be checked by using a check disc before each detection. The operation steps are as follows: first, the power switch of the instrument is turned on. And then, the probe vertically contacts with the checking color screen, so that the whole end face of the probe is tightly attached to the checking color screen, and no gap is ensured, otherwise, the accuracy of a detection result is affected. Then, the white screen and the yellow screen of the check disk are detected. At the time of detection, the display values should be 00.0 + -00.1 and 20.0+ -1, indicating that the instrument is working properly. If the detected value exceeds the range, the check disk and the probe are required to be cleaned and then the detection is carried out again. If the detected value is still found to be out of range, the jaundice instrument supplier needs to be contacted for maintenance. Finally, clinical detection can be performed after the verification is finished.

Because the controllable LED array is used for excitation, the jaundice instrument can realize the special function of automatically judging whether the skin selected area meets the measurement requirement before formally measuring the jaundice value. Firstly, a mode switching key is pressed down for several times to a selected area checking mode, at the moment, a pattern for checking the selected area appears on a screen, then the tip of a jaundice instrument probe is lightly stuck on the skin of a detected person, the whole probe end face is ensured to be clung to the skin, and a plurality of groups of measurements required by the skin selected area checking are pressed and waited for the instrument to automatically finish. In the process, the same-color LED units in the annular concentric area in the LED array of the jaundice instrument can be started to be excited one by one under the preset program of the internal main control chip, the reliability of the measurement selection area is judged by measuring and analyzing the difference between the absorption values of bilirubin on the skin of a detected person, and the judgment result is displayed on a screen to guide the continuous measurement or the replacement of the skin selection area. The process mainly aims at the difference of skin types and thicknesses of detected persons, and under the condition that whether a measurement area meets sampling standards cannot be accurately judged by visual inspection of a selected area, whether actual factors such as skin types, thicknesses, injuries, capillary vessel distribution and the like reach the degree of influencing measurement effectiveness or not is judged by using instrument measurement, so that the accuracy, comparability and stability of subsequent measurement are improved. In addition, the sensitivity and accuracy of the measurement are affected by various other factors, such as the intensity and stability of the light source, the quality and service life of the probe, the stability of the circuit and the singlechip, etc., and direct information about whether they affect the subsequent detection can be obtained in the process. For example, as shown in fig. 6, the current selected area has a pigment distribution structure under the epidermis or shallow skin, which is not obvious to the naked eye, and by sequentially exciting 4 460nm LED units located in the same outermost ring, under the same excitation intensity, it is found that after the LED units located at the rightmost side in the illustration are excited, the corresponding absorption values are obviously different from the other three absorption measurement values. When the subsequent selection area is determined, different detection schemes such as subsequent replacement selection area, calibration part effective selection area (in this example, the left half circle is selected as the effective measurement selection area) and the like are respectively triggered according to a preset threshold standard. For example: in a conventional selection decision result, a set of absorption values is a460= [0.5,0.6,0.7,0.8] whose deviation from the standard value is delta_a460= [ -0.02,0.01,0.03,0.06], by first calculating the average absorption value mean_delta_a460=sum (delta_a460)/len (delta_a460), correcting the fourth deviation value to obtain delta_a460[3] =mean_delta_a460-sum (delta_a460 [:3 ])/3, and finally calculating the corrected absorption value a460_corrected= [ a460[ i ] -delta_a460[ i ] for i in range (len (a 460)) ]. According to the above correction operation, the four absorption values will be corrected to [0.52,0.59,0.67,0.74]. If the absorption value measured at a time deviates from the normalized average value by a long distance, deleting the value according to a preset threshold value and correcting the data.

Another special function of the invention is that errors such as optical path and distribution of interferents in the optical path can be corrected by the excitation of the space-time controllable LED units. As shown in fig. 7, by sequentially exciting the same-color LED units nearer and farther from the central light trapping window, a differentiated light absorption value or absorption spectrum will be obtained. By analyzing the differentiated light absorption value or spectrum, the simple optical path deviation caused by the factors such as scattering and absorption when light passes through the sample can be eliminated; after multiple and multi-position measurement, information sets of the absorption conditions of the superficial and deep parts of the measured skin area on excitation light can be obtained, so that a structural framework of sampled skin and an interferent/object to be measured distribution three-dimensional model can be established more accurately, and errors caused by individual skin structures (such as stratum corneum thickness, epidermis breakage, vascular depth and the like) and pigment distributions (skin color, intra-tissue jaundice, vascular distribution, local pigment microdeposition and the like) are corrected according to the three-dimensional data model. These errors are identified in conventional jaundice as systematic errors that cannot be analyzed, but often affect the accuracy and stability of actual percutaneous jaundice measurements. The wavelength type of the excited LED unit is further switched, another group of information set is obtained, and compared with detection information sets under different excitation wavelengths, not only can the simple optical path difference be more accurately analyzed, but also the distribution condition of signals or interference molecules which are more sensitive to the wavelength in the shallow layer and the deep layer of the skin can be obtained. For example: when the optical path difference is smaller or the excitation LED units are positioned at different positions of the same circular ring, the long optical path and the short optical path respectively pass through the optical paths with different lengths, so that the hemoglobin absorption difference in measurement is differentiated, and the absorption value for removing the influence of hemoglobin is obtained. The subsequent correction factor is calculated based on a ratio method, i.e. the ratio of the long optical path to the short optical path, multiplied by a constant factor. This constant coefficient may be calibrated against a standard sample or calculated using known hemoglobin concentrations. After the correction coefficient is calculated, the jaundice absorption value can be corrected by using the correction coefficient, and the influence of hemoglobin on the measurement result is eliminated, so that a more accurate jaundice value is obtained. For example, in fig. 5, when the optical path difference is large, the fine structure region of the skin mainly excited will be differentiated, so that the measured absorption value will also imply the deep information of different distribution conditions of bilirubin in the epidermis, dermis, subcutaneous tissue and other regions, and it is assumed that the preset bilirubin distribution parameter array is [0.12,1.36,4.27,6.31], and the low-beam absorption model numerical matrix is [0.35,1.21,0.35;0.12,0.46,0.12, the numerical matrix of the distance absorption model is [0.12,0.27,0.83,0.27,0.12 ]; 0.26,0.35,0.73,0.35,0.26;0.08,0.15,0.40,0.15,0.08 by combining multiple and multiple area short optical path absorption value measurements, local contribution values and accuracy scoring values of the percutaneous jaundice from bilirubin concentrations of different skin layers can be obtained, so that accurate measurement values can be obtained through calculation.

In the formal measurement, the intensity of the excitation light signal can be greatly enhanced by simultaneously lighting the same-color LED units. This mode is very useful in some special application scenarios, for example for deep skin tone or strong ambient light interference. By enhancing the intensity of the excitation light signal, the jaundice instrument can provide input and output signal intensities with higher signal-to-noise ratios, thereby improving measurement accuracy and precision. The use of the technology can help doctors to diagnose jaundice more accurately, guide the formulation of treatment schemes and provide better medical services for patients.

Claims

1. Jaundice appearance based on programmable digital LED microarray, characterized in that includes: the system comprises a digital LED microarray, a photoelectric conversion module and a main control chip; the main control chip controls and drives a plurality of LED light emitting units in the digital LED microarray to emit light according to preset combination in a required period, and after each emitted light beam is absorbed by skin tissue, the light beam is transmitted to the photoelectric conversion module by the optical fiber after the trapping window to become a digitized electric signal and is transmitted to the main control chip for storage.

2. A programmable digital LED microarray-based jaundice instrument as claimed in claim 1, wherein the digital LED microarray comprises an LED excitation light array (101) and a light trapping window (102); the LED excitation light array (101) is used as a signal source, and each LED unit in the array is different in at least one parameter in terms of two parameters of the light emitting wavelength and the spatial position relative to the light trapping window (102).

3. The programmable digital LED microarray-based jaundice instrument of claim 2, wherein each LED unit in the array is a single-color LED (201) with a center emission wavelength of about 460nm, a single-color LED (202) with a center emission wavelength of 550nm, or a combination of broad-spectrum LEDs with 460nm, 550nm filters.

4. The programmable digital LED microarray-based jaundice instrument of claim 2, wherein the LED units are separated by dark light absorbing material.

5. A programmable digital LED microarray-based jaundice instrument according to claim 2, wherein for each LED unit in the LED microarray, any one or more units can be programmed to emit light for a desired period of time.

6. A programmable digital LED microarray-based jaundice instrument as claimed in claim 2, wherein the LED units are distributed concentrically and axially around the circular light trapping window (102).

7. The programmable digital LED microarray-based jaundice instrument of claim 1, wherein optical path calibration and calculation of subcutaneous deep and shallow jaundice light concentration differences are performed by controlling monochromatic excitation light at different positions in an axial direction perpendicular to the light trapping window direction (301); the uniformity of light absorption of deep and shallow tissues of the skin is judged by controlling monochromatic excitation light at different positions in a direction (401) which is concentrically parallel to the light trapping window, and an effective detection selective area is determined.

8. A method of measuring a programmable digital LED microarray-based jaundice instrument according to claim 1, comprising the steps of:

step 1, a plurality of LED units in a digital LED microarray are controlled by a main control chip to respectively emit excitation light combinations composed of 460nm and 550nm monochromatic lights with different wavelengths for one time or multiple times, wherein each beam of excitation light is scattered and refracted through skin tissues, part of light returns to a circular light trapping window area, and the light returns to a photoelectric conversion module through optical fibers after the light trapping window to be converted into a digital electric signal;

9. The method for measuring jaundice based on a programmable digital LED microarray of claim 8, wherein in step 3, LED units with the same excitation wavelength are selected simultaneously to enhance the excitation light signal.

10. The method according to claim 8, wherein in step 4, bilirubin distribution parameter sets, low beam absorption model value matrices, high beam absorption model value matrix priori parameters are preset, and local bilirubin absorption contribution values from different skin layers are analyzed by combining multiple and multi-region long and short beam absorption value measurements, so as to calculate retrospectively accurate percutaneous jaundice measurement values.