A living body detection and skin color recognition device and method

Abstract

The application discloses a kind of living body detection and skin color identification device and method, including circuit module and optical path module, the emission and collection of light source are carried out in the optical path module, the conversion processing of the light signal collected by the circuit module.This living body detection and skin color identification device and method proposed in the application increase more accurate judgment mode on the basis of original light source intensity detection, improve the living body detection precision;Solve most reflectivity or can cause the non-living body scene of capacitance change, and will not occupy additional space.In the case where confirming living body, skin color identification can also be carried out, provide additional living body information for analysis.Through chroma calculation to the measured object and judge living body, the shortcomings that single or multiple light source intensity detection for reflectivity too large surface detection failure and capacitance detection for humidity too large object detection failure can be solved;Wearing area skin color depth judgment can also be carried out by the chroma value of calculation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wearable device detection, in particular to a living body detection and skin color recognition device and method. BACKGROUND

[0002] With the development and popularization of the smart wearable market, more and more user needs are put forward, and the most prominent one is the long endurance capability of wearable devices. Since wearable devices are often limited in space, the battery capacity cannot be made large enough. In order to meet the requirement of long endurance, the device is often identified as being worn or not, so as to start the corresponding function and reduce unnecessary power consumption.

[0003] The commonly used wearing detection method at present is to detect the light source intensity through an IR light source and a photodiode module to make wearing judgment. This method is difficult to identify as not worn for some surfaces with high reflectivity, thus causing misjudgment. Living body recognition technology is widely used in various smart wearable devices. For example, smart bracelets and watches, the basic way is to use infrared light reflection intensity detection or capacitance detection to make judgment. The judgment conditions are generally single, and the recognition accuracy is not high. Since the overall structure of the smart wearable device is compact and small in size, it is difficult to implement the living body recognition function in the limited structural space. At present, the main methods are single or multiple light source intensity detection or capacitance detection, but they cannot handle all scenes. SUMMARY

[0004] To solve the problems of high misjudgment rate of wearable device living body detection and limited processing scenes, the present application provides a living body detection and skin color recognition device and method. The use of chrominance value for living body recognition can increase more accurate judgment methods on the basis of original light source intensity detection, and improve the living body detection accuracy.

[0005] In a first aspect, a living body detection and skin color recognition device includes a circuit module and a light path module. The light path module emits and collects light sources, and the circuit module converts and processes the collected light signals. The light path module specifically includes a plurality of light-emitting diodes and a plurality of photodiodes surrounding the light-emitting diodes. The light-emitting diodes and the photodiodes are arranged on a substrate, and the light-emitting diodes and the photodiodes are separated by a light separation piece.

[0006] Further, the plurality of photodiodes are arranged in a ring shape, and the plurality of light-emitting diodes are arranged at the center of the ring formed by the photodiodes.

[0007] Further, the light-emitting diodes include a green light-emitting diode of a specific wavelength, an infrared light-emitting diode, and a red light-emitting diode.

[0008] Further, the circuit module comprises a micro-control processor, a light-emitting component module, a light-receiving component module, a signal amplification module and an analog-digital conversion module, the light-emitting component module is connected to the micro-control processor module and is controlled thereby; the light-receiving component module is connected to the signal amplification module and then connected to the analog-digital conversion module, the light source signal emitted by the light-emitting component module is converted into an electric signal, the electric signal is amplified by the signal amplification module, and then the electric signal is subjected to analog-digital conversion by the analog-digital conversion module.

[0009] Further, the light-emitting component module comprises a plurality of light-emitting diodes of arbitrary wavelengths, and the light-receiving component module comprises a plurality of photodiodes.

[0010] Further, the micro-control processor further comprises a function of controlling the light-emitting mode of the light-emitting diodes according to the wearing state result to perform corresponding physiological parameter detection such as heart rate and blood oxygen saturation.

[0011] In another aspect, a living body detection and skin color recognition method is based on a living body detection and skin color recognition device, and the method is implemented by performing chroma calculation on a measured object to perform detection and recognition, and comprises the following steps.

[0012] Step S1: emitting a plurality of light sources of specific wavelengths;

[0013] Step S2: collecting the light intensity values received by the light-receiving elements after the light sources are diffusely reflected;

[0014] Step S3: performing chroma calculation by using the intensity ratio of each light source received by the light-receiving elements;

[0015] Step S4: performing living body detection and skin color recognition according to the chroma value.

[0016] Further, the step S3 specifically comprises: converting the light signal into an electric signal by the light-receiving elements through photoelectric conversion, amplifying the converted electric signal by a signal amplification circuit, and then converting the amplified electric signal into a digital signal by an analog-digital conversion circuit to perform chroma calculation.

[0017] Further, the chroma calculation comprises: obtaining current values Data1 and Data2 of each light-emitting diode when the light-emitting diode emits light, and obtaining current values Data3 and Data4 of the photodiode at this time and corresponding ADC sampling values Data5 and Data6; and the chroma value calculation formula is:

[0018] chroma = (G_gata / IR_gata);

[0019] wherein, G_gata = Data5 / ( Data1* Data3); IR_gata = Data6 / ( Data2* Data4).

[0020] Further, the step S4 specifically comprises: setting a chrominance value range, a threshold range, a black skin color chrominance range, a yellow skin color chrominance range and a white skin color chrominance range; if the calculated chrominance value is in the threshold range, it is detected as a living body, and if it is not in the threshold range, it is a non-living body; but when it is detected as a living body, the skin color is determined according to the chrominance value and the skin color chrominance range.

[0021] The present application has the following advantages: the present application provides a living body detection and skin color recognition device and method, which comprises a circuit module and a light path module, the light path module performs emission and collection of light sources, and the circuit module performs conversion processing on the collected light signals. The living body detection and skin color recognition device and method provided by the present application increase more accurate judgment mode on the basis of original light source intensity detection, improve the living body detection accuracy, solve most non-living body scenes with large reflectivity or causing capacitance change, and do not occupy additional space. In the case of confirming the living body, skin color recognition can also be performed to provide additional living body information for analysis. By performing chrominance calculation on the measured object and judging the living body, the shortcomings of single or multiple light source intensity detection for detecting surfaces with too large reflectivity and capacitance detection for detecting objects with too large humidity can be solved; the color depth of the wearing area can also be judged by the calculated chrominance value. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a flow chart of the living body detection and skin color recognition method of the present application;

[0023] Figure 2 is a circuit structure diagram in the embodiment of the present application;

[0024] Figure 3 is a light path structure diagram in the embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to have a clearer understanding of the technical features, objects and effects of the present application, the specific embodiments of the present application will be described with reference to the drawings.

[0026] The present application provides a living body detection and skin color recognition device and method, and the first aspect is a living body detection and skin color recognition device, which comprises a circuit module and a light path module, the light path module performs emission and collection of light sources, and the circuit module performs conversion processing on the collected light signals; the light path module specifically comprises a plurality of light emitting diodes and a plurality of photodiodes surrounding the light emitting diodes, the light emitting diodes and the photodiodes are arranged on a substrate, and the light emitting diodes and the photodiodes are separated by a light separation piece; the plurality of photodiodes are arranged in a ring shape, and a plurality of light emitting diodes are arranged at the center of the ring formed by the photodiodes; the light emitting diodes comprise green light emitting diodes of a specific wavelength, infrared light emitting diodes and red light emitting diodes.

[0027] The circuit module comprises a micro-control processor, a light-emitting component module, a light-receiving component module, a signal amplification module and an analog-digital conversion module, the light-emitting component module is connected to the micro-control processor module and is controlled thereby; the light-receiving component module is connected to the signal amplification module and then connected to the analog-digital conversion module, the light source signal emitted by the light-emitting component module is converted into an electric signal, the electric signal is amplified by the signal amplification module and then is subjected to analog-digital conversion by the analog-digital conversion module; the light-emitting component of the light-emitting component module comprises a plurality of light-emitting diodes of any wavelength, and the light-receiving component of the light-receiving component module comprises a plurality of photodiodes; the micro-control processor further comprises a light-emitting mode of the light-emitting diode controlled according to the wearing state result for corresponding physiological parameter detection of heart rate, blood oxygen saturation and the like.

[0028] In another aspect, a living body detection and skin color recognition method is realized based on a living body detection and skin color recognition device, and detection and recognition are realized by chroma calculation on a measured object, and the method comprises the following steps:

[0029] Step S1: emitting a plurality of light sources of specific wavelengths;

[0030] Step S2: collecting light intensity values received by a light-receiving element after diffused reflection of the light sources;

[0031] Step S3: performing chroma calculation by using the intensity ratio of each light source received by the light-receiving element;

[0032] Step S4: performing living body detection and skin color recognition according to the chroma value.

[0033] The step S3 further comprises: converting the light signal into an electric signal by the light-receiving element through photoelectric conversion, amplifying the converted electric signal by a signal amplification circuit, and then converting the amplified electric signal into a digital signal by an analog-digital conversion circuit and performing chroma calculation; the chroma calculation comprises: respectively acquiring current values Data1 and Data2 of each light-emitting diode when emitting light, and current values Data3 and Data4 of the photodiode at this time and corresponding ADC sampling values Data5 and Data6; the chroma value calculation formula is:

[0034] chroma = (G_gata / IR_gata);

[0035] wherein, G_gata = Data5 / ( Data1* Data3); IR_gata = Data6 / ( Data2* Data4)。

[0036] The step S4 specifically comprises: setting a chroma value range, a threshold value range, a black skin chroma range, a yellow skin chroma range and a white skin chroma range; if the calculated chroma value is in the threshold value range, it is detected as a living body, and if not, it is a non-living body; but when it is detected as a living body, the skin color is determined according to the chroma value and the chroma ranges of the respective skin colors.

[0037] In the embodiment, the living body detection and skin color recognition method flow is as shown in the figure Figure 1 The light source emits multiple specific wavelengths of light, which is irradiated to the surface of the measured object, and the light intensity values received by the single or multiple light sensing elements through diffuse reflection are collected; the light sensing element converts the light signal into an electrical signal through photoelectric conversion, the signal is amplified through a signal amplification circuit, and then the digital signal is converted through an analog-to-digital conversion circuit (ADC) for chroma calculation. The living body is recognized by judging whether the chroma value is in the threshold value range; if it is in the threshold value range, it is judged as a living body, and further judged which skin color interval the chroma value is in.

[0038] The light source can adopt a specific wavelength of green light emitting diode (GR), infrared light emitting diode (IR) or red light emitting diode (R); the light sensing element can adopt one or more photodiodes (PD). The light emitting device and the light sensing element are on the same substrate, and light shielding material is used between the two to prevent light from leaking between the structures.

[0039] The chroma calculation method can be: the current values Data1 and Data2 of each light emitting diode are obtained; and the current values Data3 and Data4 of the photodiode at this time and the corresponding ADC sampling values Data5 and Data6 are obtained. Taking green light and infrared light as an example: G_gata = Data5 / ( Data1* Data3), IR_gata = Data6 / ( Data62*Data4), and the chroma value chroma = (G_gata / IR_gata).

[0040] The living body detection and skin color recognition method is: assuming that the chroma value range is 0~3000, the threshold value range is 10~1500, the skin color interval is black skin 10~100, yellow skin 100~1000 and white skin 1000~1500. If the calculated chroma value is in the threshold value range, it is considered that a living body is detected, and it is further judged which skin color interval the chroma value is in, for example, the chroma value is 800, and it is identified as yellow skin.

[0041] The living body detection and skin color recognition device and method provided by the application can be applied to intelligent wearable devices, such as smart watches, smart bracelets, etc., and can be used for liveness recognition when physiological parameters such as heart rate and blood oxygen are monitored at the wrist. Figure 2The circuit structure block diagram shown includes a micro-control processor, a light-emitting component, a light-receiving component, and a digital-to-analog conversion module. The light-emitting component can be multiple light-emitting diodes of any wavelength, generally using three wavelength bands of green light, red light, and infrared light, and the number of LEDs for each wavelength band is one or more. The light-receiving component is a photodiode, generally using one or more. The light-emitting component emits multiple wavelength light sources, and the light signal received by the photodiode is calculated for chroma value after digital-to-analog conversion, and the wearing state of the smart wearable device is determined according to the chroma value. The micro-control processor can control the light-emitting mode of the light-emitting diode according to the wearing state result to perform physiological parameter detection such as heart rate and blood oxygen saturation.

[0042] In addition, the human skin color does not mutate, so the chroma value when first worn can be recorded and the skin color can be identified, and then the wearing judgment threshold interval is set based thereon; in the subsequent wearing process, if the chroma value is within the interval range, it meets the wearing, otherwise it is identified as not wearing. After each wearing confirmation, the current chroma value is recorded for skin color analysis, and by collecting chroma data for a long time, the chroma value change trend is judged, if the chroma value becomes larger, it means that the skin color becomes white, otherwise it means that the skin color becomes black.

[0043] Figure 3 For the light path structure schematic diagram in the embodiment, multiple photodiodes (PD) surround multiple light-emitting diodes (G, IR, R) in a layout mode, and are arranged on a substrate. The photodiodes (PD) and the light-emitting diodes (G, IR, R) are separated by a light-blocking piece, and the light-blocking material can be black silicone frame material with good light-blocking effect. The spacing between the photodiodes (PD) and the light-emitting diodes (G, IR, R) is not limited here, and can be designed according to the structure requirements; only the photodiodes (PD) can receive enough light signals that are diffusely reflected when wearing and on the wrist.

[0044] Among them, multiple photodiodes (PD) are arranged in a ring shape, for example, four photodiodes (PD) are evenly arranged around the ring, and multiple light-emitting diodes (G, IR, R) are arranged at the center of the ring formed by the photodiodes (PD). This arrangement is conducive to increasing the light path detection area, so that the quality of the collected light signals is better.

[0045] The present application can be widely applied to intelligent wearable devices, and since the overall structure of the intelligent wearable device is compact and small in size, it is difficult to perform live body recognition in the limited structural space. At present, single or multiple light source intensity detection or capacitance detection is mainly used, but there are scenes that cannot be handled by each method. The use of chroma value for live body recognition can increase a more accurate judgment method on the basis of original light source intensity detection, improve the live body detection accuracy, solve most non-live body scenes with high reflectivity or causing capacitance change, and will not occupy additional space. Skin color recognition can also be performed in the case of confirming the live body, and additional live body information is provided for analysis.

[0046] The present application provides a live body detection and skin color recognition device and method, including a circuit module and a light path module, the light path module emits and collects light sources, and the circuit module converts and processes the collected light signals. The live body detection and skin color recognition device and method provided by the present application increase a more accurate judgment method on the basis of original light source intensity detection, improve the live body detection accuracy, solve most non-live body scenes with high reflectivity or causing capacitance change, and will not occupy additional space. Skin color recognition can also be performed in the case of confirming the live body, and additional live body information is provided for analysis. By calculating the chroma of the measured object and judging the live body, the shortcomings of single or multiple light source intensity detection for detecting surfaces with too high reflectivity and capacitance detection for detecting objects with too high humidity can be solved. The depth of skin color in the wearing area can also be judged by the calculated chroma value.

[0047] The present application has shown and described the basic principles and main features of the present application and the advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for living body detection and skin color recognition, based on a living body detection and skin color recognition device, through chroma calculation on the measured object for detection and recognition, characterized in that, The method comprises the following steps: Step S1: emitting light sources of multiple specific wavelengths; Step S2: collecting the light intensity values received by the light elements after diffuse reflection of the light sources; Step S3: performing chroma calculation according to the intensity ratio of each light source received by the light element; Step S4: performing living body detection and skin color recognition according to the chroma value; The chroma calculation comprises: acquiring the current values of the light-emitting diodes Data1 and Data2 when the light-emitting diodes emit light, and the current values of the photodiodes Data3 and Data4 and the corresponding ADC sampling values Data5 and Data6 at the time; and the chroma value calculation formula is: chroma = (G_gata / IR_gata); Wherein, G_gata = Data5 / ( Data1* Data3); IR_gata = Data6 / ( Data2* Data4); The living body detection and skin color recognition device comprises a circuit module and a light path module, the light path module emits and collects light sources, and the circuit module converts and processes the collected light signals; the light path module specifically comprises a plurality of light-emitting diodes and a plurality of photodiodes surrounding the light-emitting diodes, the light-emitting diodes and the photodiodes are arranged on a substrate, and the light-emitting diodes and the photodiodes are separated by a light separation piece.

2. The method of claim 1, wherein the method further comprises: The plurality of photodiodes are arranged in a ring shape, and the plurality of light-emitting diodes are arranged at the center of the ring formed by the photodiodes.

3. The method of claim 1, wherein the method further comprises: The light-emitting diodes comprise green light-emitting diodes of specific wavelengths, infrared light-emitting diodes, and red light-emitting diodes.

4. The method of claim 1, wherein the method further comprises: The circuit module comprises a micro control processor, a light-emitting component module, a light-receiving component module, a signal amplification module, and an analog-digital conversion module; the light-emitting component module is connected to the micro control processor module and is controlled thereby; the light-receiving component module is connected to the signal amplification module and then connected to the analog-digital conversion module; the light source signal emitted by the light-emitting component module is converted into an electric signal, the electric signal is amplified by the signal amplification module, and then the amplified electric signal is converted into a digital signal by the analog-digital conversion module.

5. The method of claim 4, wherein the step of detecting the living body and identifying the skin color is characterized by, The light-emitting component module comprises a plurality of light-emitting diodes of any wavelength, and the light-receiving component module comprises a plurality of photodiodes.

6. The method of claim 4, wherein the step of detecting the living body and identifying the skin color is characterized by, The micro control processor further comprises a function of controlling the light-emitting mode of the light-emitting diodes according to the wearing state result to detect physiological parameters such as heart rate and blood oxygen saturation.

7. The method of claim 1-6, wherein the method further comprises: The step S3 further comprises: converting the light signal into an electric signal by the light element through photoelectric conversion, amplifying the converted electric signal by a signal amplification circuit, and then converting the amplified electric signal into a digital signal by an analog-digital conversion circuit to perform chroma calculation.

8. The method according to any one of claims 1-6, wherein the method further comprises: The step S4 specifically comprises: setting the chroma value range, the threshold value range, the black skin color chroma range, the yellow skin color chroma range, and the white skin color chroma range; if the calculated chroma value is within the threshold value range, it is detected as a living body, and if it is not within the threshold value range, it is detected as a non-living body; but when it is detected as a living body, the skin color is determined according to the chroma value and the chroma ranges of the skin colors.

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