CN114569102A

CN114569102A - Method and device for measuring biological characteristic parameters

Info

Publication number: CN114569102A
Application number: CN202011376977.5A
Authority: CN
Inventors: 袁豪
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-11-30
Filing date: 2020-11-30
Publication date: 2022-06-03
Also published as: WO2022111686A1

Abstract

The application provides a method and a device for measuring biological characteristic parameters. The method comprises the following steps: determining a target current on a first light-emitting unit which is currently lighted in a current period in the light-emitting module, respectively obtaining the current division coefficients corresponding to the first light-emitting unit and the second light-emitting unit when the target current is judged to be larger than a first preset value, and respectively distributing currents for the first light-emitting unit and the second light-emitting unit in the current period according to the current division coefficients corresponding to the first light-emitting unit and the second light-emitting unit so as to adjust the target current on the first light-emitting unit, so that the first light-emitting unit and the second light-emitting unit emit light according to the distributed currents, and the biological characteristic parameters of a target object are measured. The absolute value of the difference between the current received by the photoelectric conversion module and the second preset value is smaller than a third preset value, and the currents distributed on the first light-emitting unit and the second light-emitting unit are smaller than or equal to the first preset value. The accuracy of the measurement result of the biological characteristic parameter can be improved.

Description

Method and device for measuring biological characteristic parameters

Technical Field

The present application relates to the field of terminal technologies, and in particular, to a method and an apparatus for measuring biometric parameters.

Background

Nowadays, people pay more and more attention to their health conditions and family health conditions, and heart rate monitoring is especially important in the health conditions. Currently, the heart rate of a user can be monitored in real time by providing a photoplethysmography (PPG) sensor in a wearable device such as a smart wristwatch. The PPG sensor can control a Light Emitting Diode (LED) module to emit light, and then receives an optical signal reflected back through the skin through a Photodiode (PD), and converts the received optical signal into an electrical signal, thereby measuring the heart rate of a human body.

However, the heart rate measurement method described above has low heart rate measurement accuracy and inaccurate measurement results.

Disclosure of Invention

The application provides a method and a device for measuring biological characteristic parameters, which can improve the measurement precision of the biological characteristic parameters.

In a first aspect, the present application provides a method for measuring a biometric parameter, where the method is applied to an electronic device, the electronic device includes a light-emitting module and a photoelectric conversion module, the light-emitting module includes at least two light-emitting units, and the at least two light-emitting units are alternately turned on at different periods; the method comprises the following steps: determining a target current on a first light-emitting unit which is currently lighted in the current period in the light-emitting module; judging whether the target current on the first light-emitting unit is larger than a first preset value; if the target current on the first light-emitting unit is larger than a first preset value, acquiring a shunt coefficient corresponding to the first light-emitting unit and a shunt coefficient corresponding to the second light-emitting unit; distributing currents to the first light-emitting unit and the second light-emitting unit in the light-emitting module respectively in a current period according to the shunt coefficient corresponding to the first light-emitting unit and the shunt coefficient corresponding to the second light-emitting unit so as to adjust the target current on the first light-emitting unit, so that the first light-emitting unit and the second light-emitting unit emit light according to the distributed currents to measure the biological characteristic parameters of the target object, wherein the absolute value of the difference value between the current received by the photoelectric conversion module and the second preset value is smaller than a third preset value, and the currents distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value.

In this implementation, because the electric current that distributes all is less than or equal to first default on first luminescence unit and the second luminescence unit, consequently the partial pressure on the luminescence module is less, can guarantee from this that the voltage value on the pin of PPG sensor satisfies predetermined voltage value to for ADC provides stable reference voltage in the PPG sensor, improve the accuracy of biological characteristic parameter's measuring result. In addition, when the target current on the first light-emitting unit is larger than the first preset value, the current can be shunted to the second light-emitting unit, so that the intensity of light emitted by the light-emitting module is not reduced, the current value received by the photoelectric conversion module is larger than the second preset value, the photoelectric conversion module can normally analyze signals, and the accuracy of the measurement result of the biological characteristic parameter can be further ensured.

In a possible implementation manner, the first preset value is a maximum current value capable of ensuring that a PPG sensor in the electronic device works normally; the second preset value and the third preset value are used for ensuring that the photoelectric conversion module can normally perform signal analysis.

In the scheme, the first preset value is a maximum current value capable of ensuring normal work of the PPG sensor in the electronic equipment, and the currents distributed on the first light-emitting unit and the second light-emitting unit are limited to be less than or equal to the first preset value, so that the voltage value on a pin of the PPG sensor can be ensured to meet the preset voltage value, stable reference voltage is provided for an ADC in the PPG sensor, and the accuracy of the measurement result of the biological characteristic parameter is improved. In addition, the second preset value and the third preset value are used for ensuring that the photoelectric conversion module can normally analyze signals, and the photoelectric conversion module can normally analyze the signals by limiting the absolute value of the difference value between the current value received by the photoelectric conversion module and the second preset value to be smaller than the third preset value, so that the accuracy of the measurement result of the biological characteristic parameter can be further ensured.

In one possible implementation manner, determining a target current on a first light emitting unit currently lit in a current period in the light emitting module includes: acquiring current currently received by the photoelectric conversion module; and determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module.

In the scheme, the current value currently received by the photoelectric conversion module is received, and the target current of the first light-emitting unit is adjusted according to the current value, so that the accuracy of analyzing the signal by the photoelectric conversion module can be improved, and the accuracy of measuring the biological characteristic parameter is improved.

In a possible implementation manner, determining a target current of the first light emitting unit according to a current currently received by the photoelectric conversion module includes: judging whether the adjustment times of the target current of the first light-emitting unit is greater than a fourth preset value or not; if the number of times of adjusting the target current of the first light-emitting unit is not greater than the fourth preset value, determining whether an absolute value of a difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value; if the current is not less than the third preset value, determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module and the second preset value.

In this scheme, when the number of times of adjusting the target current of the first light-emitting unit is not greater than the fourth preset value, the target current of the first light-emitting unit is determined through the current currently received by the photoelectric conversion module, so that the phenomenon that the control module continuously adjusts the target current of the first light-emitting unit can be prevented.

In a possible implementation manner, determining a target current of the first light emitting unit according to a current currently received by the photoelectric conversion module includes: judging whether the current currently received by the photoelectric conversion module is smaller than the second preset value; if the current value is less than the second preset value, determining a target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a fifth preset value, wherein the fifth preset value is a maximum current value which can be borne by a photoplethysmography (PPG) sensor in the electronic equipment; if the current value is larger than the second preset value, determining the target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a sixth preset value, wherein the sixth preset value is a minimum current value which ensures that the PPG sensor can acquire signals.

In the scheme, the target current of the first light-emitting unit can be adjusted in real time according to the current currently received by the photoelectric conversion module, so that the measurement result of the biological characteristic parameter can be improved.

In a possible implementation manner, determining the target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a fifth preset value includes: and determining the average value of the current of the first light-emitting unit and the fifth preset value as the target current of the first light-emitting unit.

In this scheme, the target current of the first light-emitting unit is determined according to the average value of the current of the first light-emitting unit and the fifth preset value, so that the determination method is simpler.

In a possible implementation manner, determining the target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a sixth preset value includes: and determining the average value of the current of the first light-emitting unit and the sixth preset value as the target current of the first light-emitting unit.

In this scheme, the target current of the first light-emitting unit is determined according to the average value of the current of the first light-emitting unit and the sixth preset value, so that the determination method is simpler.

In one possible implementation, the method further includes: if the number of times of adjusting the target current on the first light-emitting unit is greater than the fourth preset value, or the absolute value of the difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value, judging whether the current currently received by the photoelectric conversion module meets an ideal accuracy interval of an analog-to-digital converter (ADC) of a photoplethysmography (PPG) sensor in the electronic device; if the ideal range of the accuracy of the ADC of the PPG sensor is not met, adjusting the current of the first light-emitting unit according to a preset mode, and determining the adjusted current as the target current of the first light-emitting unit; and if the ideal interval of the accuracy of the ADC of the PPG sensor is met, determining the current of the first light-emitting unit as the target current of the first light-emitting unit.

In the scheme, if the current value is not in the ideal accuracy interval of the ADC, the accuracy of the result processed by the ADC is relatively low. Therefore, when the control module judges that the current value currently received by the photoelectric conversion module is not in the ideal range of the accuracy of the ADC, the current value of the first light-emitting unit needs to be adjusted, so that the accuracy of data processing can be improved.

In a possible implementation manner, distributing currents to the first light emitting unit and the second light emitting unit in the light emitting module in a current period according to a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit respectively includes: distributing current a m to the first light-emitting unit, and distributing current b m (n-m) to the second light-emitting unit, wherein a is a shunt coefficient corresponding to the first light-emitting unit, b is a shunt coefficient corresponding to the second light-emitting unit, n is a target current on the first light-emitting unit, and m is the first preset value.

In this scheme, after the determined shunt coefficient allocates the current to the first light emitting unit and the second light emitting unit, the first light emitting unit and the second light emitting unit emit light together, and an absolute value of a difference between the current value received by the photoelectric conversion module 103 and the second preset value is smaller than a third preset value. Therefore, the accuracy of analyzing the signal by the photoelectric conversion module can be ensured, and the accuracy of measuring the biological characteristic parameters is improved.

In a possible implementation manner, a and b are both 1, wherein a distance between the first light emitting unit and the photoelectric conversion module is the same as a distance between the second light emitting unit and the photoelectric conversion module.

In this scheme, for a certain electronic device, if the distances between the first light-emitting unit and the photoelectric conversion module are equal to the distances between the second light-emitting unit and the photoelectric conversion module, the shunt coefficients corresponding to the first light-emitting unit and the second light-emitting unit are both 1, so that the current value received by the photoelectric conversion module can be ensured, and the accuracy of the measurement result can be improved.

In one possible implementation manner, a is 1, b is k, wherein a distance between the first light emitting unit and the photoelectric conversion module is smaller than a distance between the second light emitting unit and the photoelectric conversion module, and k is an integer greater than 1.

In this scheme, for a certain electronic device, if the distance between the first light-emitting unit and the photoelectric conversion module is smaller than the distance between the second light-emitting unit and the photoelectric conversion module, the current division coefficient corresponding to the first light-emitting unit is 1, and the current division coefficient corresponding to the second light-emitting unit is k, this way can not only ensure that the current value on each light-emitting unit is smaller than the first preset value, but also ensure that the measurement accuracy of the biometric parameter can approach the accuracy of the biometric parameter measured when a single light-emitting unit is lit when two light-emitting units are lit simultaneously.

In one possible implementation, the method further includes: if the target current on the first light-emitting unit is not greater than the first preset value, the first light-emitting unit emits light based on the target current to measure the biological characteristic parameter of the target object.

In this scheme, if the control module determines that the target current of the first light-emitting unit is smaller than the first preset value, it indicates that the voltage value of the first light-emitting unit is smaller, and at this time, the voltage value of the pin of the PPG sensor is larger, so that the PPG sensor can be guaranteed to normally operate.

In a second aspect, the present application provides a device, which includes a light emitting module and a photoelectric conversion module, where the light emitting module includes at least two light emitting units, and the at least two light emitting units are alternately turned on at different periods; the device also includes: a control module; the control module is used for determining a target current on a first light-emitting unit which is lighted currently in a current period in the light-emitting module; the control module is also used for judging whether the target current on the first light-emitting unit is greater than a first preset value; the control module is further configured to obtain a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit when the target current on the first light emitting unit is greater than a first preset value; the control module is further configured to allocate currents to the first light emitting unit and the second light emitting unit in the light emitting module respectively in a current period according to a current division coefficient corresponding to the first light emitting unit and a current division coefficient corresponding to the second light emitting unit, so as to adjust a target current on the first light emitting unit, so that the first light emitting unit and the second light emitting unit emit light according to the allocated currents, and to measure a biometric parameter of a target object, wherein an absolute value of a difference between the current received by the photoelectric conversion module and a second preset value is smaller than a third preset value, and the currents allocated to the first light emitting unit and the second light emitting unit are both smaller than or equal to the first preset value.

In a possible implementation manner, the first preset value is a maximum current value capable of ensuring that a PPG sensor in the device works normally; the second preset value and the third preset value are used for ensuring that the photoelectric conversion module can normally perform signal analysis.

In a possible implementation manner, the control module is specifically configured to: acquiring current currently received by the photoelectric conversion module; and determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module.

In a possible implementation manner, the control module is specifically configured to: judging whether the adjustment times of the target current of the first light-emitting unit is greater than a fourth preset value or not; if the number of times of adjusting the target current of the first light-emitting unit is not greater than the fourth preset value, determining whether an absolute value of a difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value; if the current is not less than the third preset value, determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module and the second preset value.

In a possible implementation manner, the control module is specifically configured to: judging whether the current currently received by the photoelectric conversion module is smaller than the second preset value; if the current value is less than the second preset value, determining a target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a fifth preset value, wherein the fifth preset value is a maximum current value which can be borne by a photoplethysmography (PPG) sensor in the device; if the current value is larger than the second preset value, determining the target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a sixth preset value, wherein the sixth preset value is a minimum current value which ensures that the PPG sensor can acquire signals.

In a possible implementation manner, the control module is specifically configured to: and determining the average value of the current of the first light-emitting unit and the fifth preset value as the target current of the first light-emitting unit.

In a possible implementation manner, the control module is specifically configured to: and determining the average value of the current of the first light-emitting unit and the sixth preset value as the target current of the first light-emitting unit.

In one possible implementation manner, the control module is further configured to: if the number of times of adjusting the target current on the first light-emitting unit is greater than the fourth preset value, or the absolute value of the difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value, judging whether the current currently received by the photoelectric conversion module meets an ideal accuracy interval of an analog-to-digital converter (ADC) of a photoplethysmography (PPG) sensor in the device; if the ideal interval of the accuracy of the ADC of the PPG sensor is not met, adjusting the current of the first light-emitting unit according to a preset mode, and determining the adjusted current as the target current of the first light-emitting unit; and if the ideal interval of the accuracy of the ADC of the PPG sensor is met, determining the current of the first light-emitting unit as the target current of the first light-emitting unit.

In a possible implementation manner, the control module is specifically configured to: distributing current a m to the first light-emitting unit, and distributing current b m (n-m) to the second light-emitting unit, wherein a is a shunt coefficient corresponding to the first light-emitting unit, b is a shunt coefficient corresponding to the second light-emitting unit, n is a target current of the first light-emitting unit, and m is the first preset value.

In one possible implementation, the control module is further configured to: when the target current on the first light-emitting unit is not larger than the first preset value, the first light-emitting unit emits light based on the target current to measure the biological characteristic parameter of the target object.

In a third aspect, the present application provides an electronic device, comprising: the LED module comprises at least two light-emitting units, and the at least two light-emitting units are lighted in turn in different periods; the memory is used for storing program instructions; the processor is configured to invoke program instructions in the memory to perform a method according to the first aspect or any one of its possible implementations.

In a fourth aspect, the present application provides a chip comprising at least one processor and a communication interface, the communication interface and the at least one processor being interconnected by a line, the at least one processor being configured to execute a computer program or instructions to perform the method according to the first aspect or any one of the possible implementations thereof.

In a fifth aspect, the present application provides a computer readable medium storing program code for execution by a computer, the program code comprising instructions for performing the method according to the first aspect or any one of its possible implementations.

The method and the device for measuring the biological characteristic parameters provided by the embodiment of the application determine the target current on the first light-emitting unit which is currently lighted in the current period in the light-emitting module, and determining whether the target current of the first light-emitting unit is greater than a first preset value, if it is determined that the target current of the first light-emitting unit is greater than the first preset value, the control module may obtain the shunt coefficient corresponding to the first light emitting unit and the shunt coefficient corresponding to the second light emitting unit, and according to the shunt coefficient corresponding to the first light-emitting unit and the shunt coefficient corresponding to the second light-emitting unit, respectively distributing current to a first light-emitting unit and a second light-emitting unit in the light-emitting module in the current period, so as to adjust the target current on the first light-emitting unit, so that the first light-emitting unit and the second light-emitting unit emit light according to the distributed current to measure the biological characteristic parameter of the target object. The absolute value of the difference value between the current value received by the photoelectric conversion module and the second preset value is smaller than a third preset value, and the current values distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value. Because the currents distributed on the first light-emitting unit and the second light-emitting unit are less than or equal to the first preset value, the partial pressure on the light-emitting module is small, so that the voltage value on the pin of the PPG sensor can meet the preset voltage value, stable reference voltage is provided for the ADC in the PPG sensor, and the accuracy of the measurement result of the biological characteristic parameter is improved. In addition, when the target current on the first light-emitting unit is greater than the first preset value, the current can be shunted to the second light-emitting unit, so that the intensity of light emitted from the light-emitting module is not reduced, the absolute value of the difference between the current value received by the photoelectric conversion module 103 and the second preset value can be smaller than the third preset value, the photoelectric conversion module can normally analyze signals, and the accuracy of the measurement result of the biological characteristic parameter can be further ensured.

Drawings

Fig. 1 is an application scenario diagram of a measurement method of a biometric parameter provided in an embodiment of the present application;

FIG. 2 is a schematic diagram illustrating a biometric parameter measurement provided by an embodiment of the present application;

fig. 3 is a schematic structural diagram of the wearable device 11;

fig. 4 is a schematic flow chart of a method for measuring a biometric parameter according to an embodiment of the present disclosure;

fig. 5 is another schematic flow chart of a method for measuring a biometric parameter according to an embodiment of the present disclosure;

FIG. 6 is a schematic illustration of determining a split coefficient;

fig. 7 is a schematic distance diagram of the light emitting unit and the photoelectric conversion module;

fig. 8 is another distance schematic diagram of the light emitting unit and the photoelectric conversion module;

FIG. 9 is a schematic structural diagram of a biometric parameter measurement apparatus according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

The terms "first", "second" and "third", etc. in the description and claims of this application and the description of the drawings are used for distinguishing between different objects and not for limiting a particular order.

In the embodiments of the present application, words such as "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g.," is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present relevant concepts in a concrete fashion.

In the embodiments of the present application, "at least one" means one or more, "a plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone, wherein A and B can be singular or plural. In the description of the text of the present application, the character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

Embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Fig. 1 is an application scenario diagram of a measurement method of a biometric parameter provided in an embodiment of the present application, and as shown in fig. 1, the embodiment of the present application may be applied to a scenario in which a target object 12 wears a wearable device 11 to measure a biometric parameter of the target object, where the biometric parameter may include a heart rate, a blood oxygen saturation level, or a blood pressure. All use biometric parameter to explain as the example in this application embodiment for the heart rate, when being other parameters to biometric parameter, thereby can be that PPG sensor control LED module sends the light of different colours and measures and obtain, for example, when PPG sensor control LED module sent red light, can measure the oxyhemoglobin saturation of target object 12. When the biometric parameter is other parameters, the measurement principle is similar to that when the biometric parameter is a heart rate, and details are not repeated in the embodiment of the application.

For example, the wearable device 11 may also be referred to as a wearable smart device, which is a generic term for intelligently designing daily wearing and developing wearable devices, such as glasses, gloves, watches, clothing, shoes, and so on, by applying wearable technology. A wearable device is a portable device that is worn directly on the body or integrated into the clothing or accessories of the user. The wearable device 11 is not only a hardware device, but also realizes powerful functions through software support, data interaction and cloud interaction. The generalized wearable smart device includes full functionality, large size, and can implement full or partial functionality without relying on a smart phone, such as: smart watches or smart glasses and the like, and only focus on a certain type of application functions, and need to be used in cooperation with other devices such as smart phones, such as various smart bracelets for physical sign monitoring, smart jewelry and the like. In addition, the wearable device 11 may also be a sports wrist band, an infrared ear heart rate sensor, a heart rate monitoring chest band, or the like.

Illustratively, the target object 12 may be a user.

Fig. 2 is a schematic diagram of a biometric parameter measurement principle provided in an embodiment of the present application, and as shown in fig. 2, the target object 12 may measure its own heart rate by wearing the wearable device 11. The wearable device 11 includes an LED module 101, a PPG sensor 102, a photoelectric conversion module 103, and a control module 104. The LED module 101 includes at least two light emitting units, the photoelectric conversion module 103 may be a PD, and the control module 104 may be a Central Processing Unit (CPU) or a Micro Controller Unit (MCU), for example.

When heart rate measurement is performed, the PPG sensor 102 controls the light-emitting units in the LED modules 101 to emit light, and since the wearable device 11 is worn on the skin surface of the target subject 12, a part of the emitted light is absorbed by hemoglobin in blood after the emitted light is irradiated to the skin of the target subject 12, and the light which is not absorbed is reflected. The photoelectric conversion module 103 receives the light signal reflected back through the skin, converts the received light signal into an electrical signal, and sends the electrical signal to the control module 104, and the control module 104 processes the electrical signal to obtain the heart rate of the target object 12.

Fig. 3 is a schematic structural diagram of the wearable device 11, and as shown in fig. 3, the LED module 101 includes at least two light emitting units, which is described in the embodiment of the present application by taking four light emitting units as an example, wherein the four light emitting

units

1011, 1012, 1013, and 1014 are respectively connected to pin pins of the PPG sensor, and the light emitting units may be LEDs. In addition, the PPG sensor 102 controls the

light emitting units

1011 and 1013 to emit red light, and controls the

light emitting units

1012 and 1014 to emit green light. It is to be understood that the light emitting unit 1011, the light emitting unit 1012, the light emitting unit 1013, and the light emitting unit 1014 may be polled for lighting. When the light emitting unit 1011 and the light emitting unit 1013 are turned on, the blood oxygen saturation of the target subject 12 may be measured with the wearable device 11, and when the light emitting unit 1012 and the light emitting unit 1014 are turned on, the heart rate of the target subject 12 may be measured with the wearable device 11.

The PPG sensor 102 includes a data buffer and an Analog-to-digital converter (ADC), wherein the ADC is connected to the photoelectric conversion module 103. When the PPG sensor 102 controls the light emitting unit 1011, the light emitting unit 1012, the light emitting unit 1013, and the light emitting unit 1014 to be polled, and light is irradiated to the skin and reflected by the skin, the photoelectric conversion module 103 receives the reflected light signal and converts the light signal into an electrical signal. The photoelectric conversion module 103 sends the electrical signal to an ADC in the PPG sensor 102, which converts the electrical signal into a digital signal and sends it to a data buffer. After the light emitting unit 1011, the light emitting unit 1012, the light emitting unit 1013, and the light emitting unit 1014 are all lit once, digital signals corresponding to the light emitting unit 1011, the light emitting unit 1012, the light emitting unit 1013, and the light emitting unit 1014, respectively, will be stored in the data buffer. The PPG sensor 102 sends the digital signals stored in the data buffer to the control module 104 via a Serial Peripheral Interface (SPI). The control module 104 processes the received digital signal to obtain parameters such as heart rate or blood oxygen saturation of the target object 12.

One embodiment is that since the light emitting unit 1011, the light emitting unit 1012, the light emitting unit 1013, and the light emitting unit 1014 are polling-lighted, only one light emitting unit is usually lighted at each time. Hereinafter, the light-emitting unit 1011 is described as an example of lighting, and when other light-emitting units are lighted, the description is omitted here similarly to when the light-emitting unit 1011 is lighted. As shown in fig. 3, since the light emitting unit 1011 is not an ideal device, as the current on the light emitting unit 1011 increases, the resistance of the light emitting unit 1011 exceeds the ideal resistance, and thus the voltage value increases sharply, so that the actual divided voltage value on the light emitting unit 1011 is much larger than the on voltage value of the light emitting unit 1011. Since the power supply of the LED module 101 is 5V, when the voltage value of the light emitting unit 1011 is large, the voltage value of the pin of the PPG sensor 102 is small. As will be appreciated by those skilled in the art, the PPG sensor 102 can work properly because the voltage on the pin of the PPG sensor 102 must satisfy the preset voltage value. When the voltage value of the pin of the PPG sensor 102 does not reach the preset voltage value, the PPG sensor 102 may work abnormally, and then the reference voltage of the ADC in the PPG sensor 102 may be unstable, which may cause the result of the digital signal converted by the ADC to be inaccurate, and may cause the accuracy of the measurement result analyzed by the control module 104 to be low.

To solve this problem, in one embodiment, the divided voltage of the light-emitting unit included in the LED module 101 is reduced by limiting the value of the current flowing through the light-emitting unit to ensure that the voltage of the pin of the PPG sensor 102 meets the preset threshold, so as to ensure that the ADC has a stable reference voltage to improve the measurement accuracy of the biometric parameter.

However, in the above manner, because the body tissue conditions outside the blood vessels of different users are different, the skin of some users has high light absorption, after the current value of the light emitting unit is limited, the light intensity of the light emitted by the light emitting unit is low, and after the light is absorbed by the skin of the users, the light reflected to the photoelectric conversion module 103 is less, so that the electrical signal obtained after the conversion by the photoelectric conversion module 103 is also small, and if the value of the electrical signal is smaller than the value of the signal that can be normally analyzed by the photoelectric conversion module 103, the measurement result of the biometric parameter is inaccurate.

In order to solve the above problem, an embodiment of the present application provides a method for measuring a biometric parameter, in which a control module 104 determines a target current of a first light emitting unit currently lit in a current period in a light emitting module, and determines whether the target current of the first light emitting unit is greater than a first preset value, if it is determined that the target current of the first light emitting unit is greater than the first preset value, the control module 104 may obtain a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to a second light emitting unit, and allocate currents to the first light emitting unit and the second light emitting unit in the light emitting module in the current period according to the shunt coefficient corresponding to the first light emitting unit and the shunt coefficient corresponding to the second light emitting unit, so as to adjust the target current of the first light emitting unit, and enable the first light emitting unit and the second light emitting unit to emit light according to the allocated currents, to measure a biometric parameter of the target object. The absolute value of the difference between the current value received by the photoelectric conversion module 103 and the second preset value is smaller than a third preset value, wherein the current values distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value. Because the currents distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value, the divided voltage on the light-emitting module 101 is smaller, so that the voltage value on the pin of the PPG sensor 102 can be ensured to meet the preset voltage value, a stable reference voltage is provided for the ADC in the PPG sensor 102, and the accuracy of the measurement result of the biometric parameter is improved. In addition, when the target current on the first light-emitting unit is greater than the first preset value, the current can be shunted to the second light-emitting unit, so that the intensity of light emitted from the light-emitting module is not reduced, the current value received by the photoelectric conversion module 103 can be greater than the second preset value, the photoelectric conversion module 103 can be ensured to normally analyze signals, and the accuracy of the measurement result of the biological characteristic parameter can be further ensured.

The technical solution of the measurement method of biometric parameters provided in the present application is described in detail below by means of detailed examples. It is to be understood that the following detailed description may be combined with other embodiments, and that the same or similar concepts or processes may not be repeated in some embodiments.

Fig. 4 is a flow chart of a method for measuring a biometric parameter provided in an embodiment of the present application, and it should be noted that although in the embodiment of the present application, the steps of the method are presented in a specific order, the order of the steps may be changed in different embodiments, and in some embodiments, one or more steps shown in the order in the present specification may be performed simultaneously. As shown in fig. 4, the method includes:

step 401: the control module 104 determines a target current of a first light emitting unit within the light emitting module 101.

In this step, the light emitting module 101 includes at least two light emitting units, and the at least two light emitting units are connected in parallel, and the light emitting units may be LEDs, for example. The control module 104 controls the light-emitting units to be polled and lighted through the PPG sensor 102. The first light-emitting unit is a light-emitting unit which is lighted currently in the current period. Wherein the smaller the current value of the first light-emitting unit, the smaller the intensity of the light emitted by the first light-emitting unit.

It should be understood that when the current value of the first light-emitting unit in the light-emitting module 101 is smaller, the intensity of the light emitted by the first light-emitting unit is smaller, and thus the light signal received by the photoelectric conversion module 103 is smaller. Therefore, in order to ensure the magnitude of the current value received by the photoelectric conversion module 103, the control module 104 may adjust the current of the first light emitting unit in the light emitting module 101 in real time according to the current received by the photoelectric conversion module 103.

Next, a process of how the control module 104 determines the target current value of the first light-emitting unit in the light-emitting module 101 is described in detail through the embodiment shown in fig. 5.

Specifically, fig. 5 is another schematic flow chart of a method for measuring a biometric parameter according to an embodiment of the present application, and as shown in fig. 5, the method includes:

step 4011, the control module 104 receives the current currently received by the photoelectric conversion module 103 sent by the PPG sensor 102.

In this step, in order to ensure the magnitude of the current received by the photoelectric conversion module 103, the control module 104 may adjust the current of the first light emitting unit in the light emitting module 101 in real time according to the current currently received by the photoelectric conversion module 103. After converting the received optical signal into a current signal, the photoelectric conversion module 103 sends the current signal to an ADC of the PPG sensor 102, so as to convert the analog current signal into a digital current signal and store the digital current signal in a data buffer. The PPG sensor 102 sends the current signal in the data buffer to the control module 104 through the SPI bus, so that the control module 104 can obtain the current currently received by the photoelectric conversion module 103.

Step 4012, the control module 104 determines whether the adjustment frequency of the target current on the first light emitting unit is greater than a fourth preset value.

If yes, go to step 4018, otherwise, go to step 4013.

In this step, in order to prevent the control module 104 from continuously adjusting or shunting the target current on the first light emitting unit, after it is determined that the target current on the first light emitting unit has been adjusted or shunted many times before the control module 104 determines, the target current on the first light emitting unit will not be continuously adjusted accurately, but it is determined whether the current currently received by the photoelectric conversion module 103 meets an ideal interval of the accuracy of the ADC in the PPG sensor. Step 4013 is executed only if it is determined that the number of times the target current on the first light emitting unit is adjusted or shunted before the control module 104 is not greater than the fourth preset value.

The fourth preset value may be set according to actual conditions or experience, for example, may be 3 or 4, and a specific value of the fourth preset value is not limited herein.

In step 4013, the control module 104 determines whether an absolute value of a difference between the current currently received by the photoelectric conversion module 103 and the second preset value is smaller than a third preset value.

If yes, go to step 4018, otherwise, go to step 4014.

In this step, the second preset value and the third preset value are used to ensure that the photoelectric conversion module 103 can perform signal analysis normally. When the current value currently received by the photoelectric conversion module 103 is close to the second preset value, the result obtained when the photoelectric conversion module 103 analyzes the signal is relatively accurate, and therefore, if the control module 104 determines that the absolute value of the difference between the current value currently received by the photoelectric conversion module 103 and the second preset value is not smaller than the third preset value, that is, if the difference between the current value currently received by the photoelectric conversion module 103 and the second preset value is relatively large, it indicates that the current value currently received by the photoelectric conversion module 103 may be too large or too small, and at this time, the current on the first light-emitting unit needs to be adjusted.

For example, if the second preset value is 100mA and the third preset value is 10mA, step 4018 is executed when the current value currently received by the photoelectric conversion module 103 is within the interval [90,110], otherwise, step 4014 is executed.

Step 4014, the control module 104 determines whether the current currently received by the photoelectric conversion module 103 is greater than the second preset value.

If yes, go to step 4016; otherwise, step 4015 is performed.

Step 4015, the control module 104 determines a target current value according to the fifth preset value and the current of the first light emitting unit.

The fifth preset value is the maximum current value which can be borne by the PPG sensor, and is determined by the chip characteristic of the PPG sensor.

In this step, since the current value of the first light-emitting unit can be controlled by the control module 104 in real time, the current value of the first light-emitting unit can be understood as the current value of the first light-emitting unit determined by the control module 104 last time.

When the control module 104 determines that the current currently received by the photoelectric conversion module 103 is smaller than the second preset value, it indicates that the current value of the photoelectric conversion module 103 is smaller, and at this time, in order to ensure that the photoelectric conversion module 103 can correctly analyze the signal, the current value of the first light-emitting unit needs to be increased to increase the light intensity of the first light-emitting unit, so as to achieve the purpose of increasing the current value of the photoelectric conversion module 103.

In one possible implementation, an average value of the fifth preset value and a current value of the first light emitting unit in the current period may be determined as the target current value. In another possible implementation manner, the target current value may also be determined according to a preset weight value and according to a fifth preset value and a current value of the first light-emitting unit in the current period. Of course, the target current value may also be determined in other manners, for example, a value is randomly selected between the fifth preset value and the current value of the first light-emitting unit in the current period as the target current value, and so on, as long as the determined target current value is greater than the current value of the first light-emitting unit in the current period and is less than the fifth preset value.

Step 4016, the control module 104 determines a target current value according to the sixth preset value and the current of the first light emitting unit.

The sixth preset value is the minimum current value which ensures that the PPG sensor can acquire signals, and is determined by the chip characteristic of the PPG sensor.

In this step, when the control module 104 determines that the current value currently received by the photoelectric conversion module 103 is greater than the second preset value, it indicates that the current value of the photoelectric conversion module 103 is greater, and at this time, in order to ensure that the photoelectric conversion module 103 can correctly analyze the signal, the current value of the first light-emitting unit needs to be reduced to reduce the light intensity of the first light-emitting unit, so as to achieve the purpose of reducing the current value of the photoelectric conversion module 103.

In one possible implementation, the sixth preset value and an average value of the current values of the first light emitting unit in the current period may be determined as the target current value. In another possible implementation manner, the target current value may also be determined according to a preset weight value and according to a sixth preset value and a current value of the first light-emitting unit in the current period. Of course, the target current value may also be determined in other manners, for example, a value is randomly selected between the sixth preset value and the current value of the first light-emitting unit in the current period as the target current value, and so on, as long as the determined target current value is smaller than the current value of the first light-emitting unit in the current period and is larger than the sixth preset value.

In step 4017, the control module 104 determines the target current value as the target current of the first light emitting unit.

In this step, the control module 104 may adjust or update the current value of the first light emitting unit to the target current value after determining the target current value.

Step 4018, the control module 104 determines whether the current value currently received by the photoelectric conversion module 103 meets an ideal interval of ADC accuracy.

If yes, go to step 4020; otherwise, step 4019 is performed.

In this step, the ideal interval of the ADC accuracy may also be understood as that when the current value is in the interval, the accuracy of the result after the ADC processing is relatively high. If the current value currently received by the photoelectric conversion module 103 is within the interval, the current value of the first light emitting unit is not adjusted.

If the current value is not within the interval, the result processed by the ADC has relatively low accuracy. Therefore, when the control module 104 determines that the current value currently received by the photoelectric conversion module 103 is not within the ideal range of the ADC accuracy, the current value of the first light emitting unit needs to be adjusted.

In addition, the control module 104 determines whether the current value currently received by the photoelectric conversion module 103 meets an ideal range of ADC accuracy, or the control module 104 determines whether the current value currently received by the photoelectric conversion module 103 is within a saturation range of the ADC, if so, the accuracy of the result processed by the ADC is low, at this time, step 4019 is executed, and if not, the accuracy of the result processed by the ADC is relatively high, at this time, step 4020 is executed.

Step 4019, the control module 104 adjusts a current of the first light emitting unit according to a preset manner, and determines the adjusted current as a target current of the first light emitting unit.

In this step, if the control module 104 determines that the current value currently received by the photoelectric conversion module 103 is not in the ideal range of the ADC accuracy, or the control module 104 determines that the current value currently received by the photoelectric conversion module 103 is in the saturation range of the ADC, the control module 104 needs to adjust the current value of the first light emitting unit. For example, the current value to be currently received by the photoelectric conversion module 103 may be obtained in step 4011 each time after the current value of the first light emitting unit is adjusted by the preset current value, and if the current value currently received by the photoelectric conversion module 103 is still not in the ideal ADC accuracy interval or is in the saturation interval of the ADC, the current value currently received by the photoelectric conversion module 103 may be continuously adjusted by the preset current value until the current value currently received by the photoelectric conversion module 103 is in the ideal ADC accuracy interval or is not in the saturation interval of the ADC.

The current adjusting efficiency can be improved by adjusting the current value of the first light emitting unit in a stepping mode.

In this embodiment, by receiving the current value currently received by the photoelectric conversion module 103 and adjusting the current value of the first light-emitting unit according to the current value, which is sent by the PPG sensor 102, the accuracy of analyzing the signal by the photoelectric conversion module 103 can be improved, so as to improve the accuracy of measuring the biometric parameter.

In step 4020, the control module 104 determines the current of the first light emitting unit as the target current of the first light emitting unit.

If the current value currently received by the photoelectric conversion module 103 meets the ideal ADC accuracy interval, it indicates that the accuracy of the result processed by the ADC is relatively high, and at this time, the current of the first light-emitting unit may be determined as the target current of the first light-emitting unit.

In step 402, the control module 104 determines whether the target current of the first light-emitting unit is greater than a first preset value.

If the target current of the first light emitting unit is greater than the first preset value, step 403 is executed, otherwise, step 406 is executed.

The first preset value is a maximum current value capable of ensuring normal operation of the PPG sensor, and the first preset value may be 100mA, for example.

In this step, when the target current of the first light emitting unit is greater than the first preset value, since the first light emitting unit is an undesirable device, its actual resistance value will exceed the ideal resistance value, and when the current value is large, the actual working voltage thereon will exceed the turn-on voltage, so that the voltage value on the pin of the PPG sensor will be reduced. Therefore, in order to ensure the magnitude of the voltage value on the pin of the PPG sensor, the control module 104 may control to shunt the target current on the first light-emitting unit to shunt the target current value of the first light-emitting unit to other light-emitting units, so as to reduce the voltage value of the light-emitting module 101, thereby ensuring the magnitude of the voltage value on the pin of the PPG sensor.

In step 403, the control module 104 obtains a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit.

The shunt coefficient is used for adjusting current values of the first light-emitting unit and the second light-emitting unit. According to the current splitting coefficient corresponding to the first light emitting unit, the current splitting coefficient corresponding to the second light emitting unit, and the target current of the first light emitting unit determined by the control module 104, currents may be respectively distributed to the first light emitting unit and the second light emitting unit in the current period, and when the first light emitting unit and the second light emitting unit are controlled to be simultaneously turned on, the current value received by the photoelectric conversion module 103 is the same as the current value received by the photoelectric conversion module 103 when only the first light emitting unit is turned on according to the target current value.

In a possible implementation manner, the shunt coefficient may be obtained by collecting multiple sets of current values of the two light emitting units and fitting the multiple sets of current values. Next, the following description will be given taking the case of collecting three sets of data. Specifically, at a first time, a current value Data1-1 on the first light emitting unit can be collected, a current value Data2-1 on the second light emitting unit can be collected, at a second time, a current value Data1-2 on the first light emitting unit can be collected, a current value Data2-2 on the second light emitting unit can be collected, at a third time, a current value Data1-3 on the first light emitting unit can be collected, and a current value Data2-3 on the second light emitting unit can be collected. After data is collected, the data can be formulated

The initial split coefficient K' is calculated, where i can have values of 1, 2, 3. After K 'is calculated, the K' can be substituted into a preset shunting algorithm, and a linear regression optimization method is used to obtain the optimized shunting coefficient.

In the mode, the shunting coefficients are determined in a fitting mode by collecting multiple groups of current values, so that the determined shunting coefficients are more accurate.

In another possible implementation manner, the shunt factor may also be obtained by collecting a set of current values of the two light emitting units, and analyzing the set of current values. For example, fig. 6 is a schematic diagram for determining the shunt coefficient, as shown in fig. 6, the two light emitting units are LED1 and LED2, respectively, where the distance between LED1 and PD is distance 1, the distance between LED2 and PD is distance 2, and the distance 1 is greater than the distance 2, and since the distances between LED1 and LED2 and PD are different, the current values received by PD are different when the currents on LED1 and LED2 are the same. For example, when the operating current of the LED1 is 100mA, a part of light emitted from the LED1 is reflected to the PD through the skin after the light is irradiated to the skin, the PD converts an optical signal into an electrical signal, and the PD receives a current of 10mA, whereas when the operating current of the LED2 is 100mA, a part of light emitted from the LED2 is reflected to the skin after the light is irradiated to the skin, a part of light is reflected to the PD through the skin, the PD converts an optical signal into an electrical signal, and the PD receives a current of 5 mA. Therefore, the current division factor corresponding to the LED1 may be 1, and the current division factor corresponding to the LED2 may be 2, that is, when the operating current of the LED2 is 2 × 100mA, the current received by the PD is 10mA, and at this time, the current received by the PD is the same as the current received when the LED1 operates at 100 mA.

In the method, a set of current values of the two light-emitting units is collected, and the set of current values is analyzed to determine the shunt coefficient corresponding to each light-emitting unit, so that the method for determining the shunt coefficient is simpler.

In yet another possible implementation manner, the control module 104 may store a corresponding relationship between each light-emitting unit and the corresponding shunt coefficient thereof in advance, and the control module 104 may determine the shunt coefficient corresponding to each light-emitting unit by querying the corresponding relationship. The corresponding relationship may be stored in a table manner, or may also be stored in a list manner, and of course, the corresponding relationship may also be stored in other manners, and the specific storage manner of the corresponding relationship is not limited herein.

In this way, the pre-stored correspondence between the light-emitting units and the shunt coefficients can be used to determine the shunt coefficients corresponding to each light-emitting unit, so that the method for determining the shunt coefficients is simple and efficient.

It should be understood that, for a certain wearable device, if the distances between the first light-emitting unit and the photoelectric conversion module PD included in the wearable device and the distances between the second light-emitting unit and the photoelectric conversion module PD are the same, the shunt coefficients corresponding to the first light-emitting unit and the second light-emitting unit are both 1. If the distances between the first light-emitting unit and the photoelectric conversion module PD are different, if the distance between the first light-emitting unit and the photoelectric conversion module PD is smaller than the distance between the second light-emitting unit and the photoelectric conversion module PD, the shunt coefficient corresponding to the first light-emitting unit may be 1, the shunt coefficient corresponding to the second light-emitting unit may be k1, and k1 is greater than 1, or the shunt coefficient corresponding to the first light-emitting unit may be k2, the shunt coefficient corresponding to the second light-emitting unit may be 1, and k2 is smaller than 1.

Step 404, the control module 104 allocates currents to the first light emitting unit and the second light emitting unit in the light emitting module 101 in the current period according to the current dividing coefficient corresponding to the first light emitting unit and the current dividing coefficient corresponding to the second light emitting unit, so as to adjust the target current on the first light emitting unit, so that the first light emitting unit and the second light emitting unit emit light according to the allocated currents, so as to measure the biometric parameter of the target object, wherein an absolute value of a difference between a current value received by the photoelectric conversion module 103 and a second preset value is smaller than a third preset value, and current values allocated to the first light emitting unit and the second light emitting unit are both smaller than or equal to the first preset value.

The second preset value is a current value at which the photoelectric conversion module 103 can normally perform signal analysis.

Specifically, in one embodiment, the first light emitting unit and the second light emitting unit are in polling lighting, and therefore, only the first light emitting unit should be lighted according to the target current at the present time. However, since the target current is greater than the first preset value, the target current needs to be shunted to other light emitting units, for example, a part of the current value may be shunted to the second light emitting unit. Illustratively, as shown in fig. 3, since both the light emitting unit 1011 and the light emitting unit 1013 emit red light and both the light emitting unit 1012 and the light emitting unit 1014 emit green light, the second light emitting unit may be 1013 if the first light emitting unit is 1011, or the second light emitting unit may be 1011 if the first light emitting unit is 1013, or the second light emitting unit may be 1014 if the first light emitting unit is 1012, or the second light emitting unit may be 1012 if the first light emitting unit is 1014.

After determining the current division coefficient corresponding to the first light emitting unit and the current division coefficient corresponding to the second light emitting unit, the control module 104 allocates current values to the first light emitting unit and the second light emitting unit according to the current division coefficients. The first light-emitting unit and the second light-emitting unit emit light based on the distributed current, the photoelectric conversion module can receive the light signal reflected by the skin, convert the light signal into an electric signal, and send the electric signal to the control module 104, and the control module 104 can obtain the biological characteristic parameters of the target object by processing the electric signal.

In order to ensure the accuracy of the measurement result, for wearable devices in which the distances between the first light-emitting unit and the photoelectric conversion module are equal to those between the second light-emitting unit and the photoelectric conversion module, the shunt coefficients corresponding to the first light-emitting unit and the second light-emitting unit are both 1, and if the target current of the first light-emitting unit is n and the first preset value is m, the control module alternately allocates currents of m and n-m to the first light-emitting unit and the second light-emitting unit.

Specifically, fig. 7 is a schematic distance diagram of the light-emitting unit and the photoelectric conversion module, as shown in fig. 7, for a certain wearable device, the wearable device includes a light-emitting unit LED1 and an LED2, where the distance between the LED1 and the distance between the LED2 and the photoelectric conversion module PD are the same. At this time, the current division coefficients corresponding to the light emitting units LED1 and LED2 are both 1. When the control module 104 distributes the current, it is assumed that at the first time, the control module 104 determines that the target current of the light-emitting unit LED1 is n, and the current n is greater than the first preset value m, and at this time, the control module may distribute the current m to the light-emitting unit LED1 and distribute the current n-m to the light-emitting unit LED 2.

Further, to ensure accuracy of the measurement results, at the second time, the control module 104 may distribute the current n-m to the light emitting unit LED1, the current m to the light emitting unit LED2, and at the third time, the control module 104 may distribute the current m to the light emitting unit LED1, the current n-m to the light emitting unit LED2, and so on.

For wearable devices in which the distances between the first light-emitting unit and the photoelectric conversion module are not equal to each other, assuming that the distance between the first light-emitting unit and the photoelectric conversion module is smaller than the distance between the second light-emitting unit and the photoelectric conversion module PD, the shunt coefficient corresponding to the first light-emitting unit may be 1, and the shunt coefficient corresponding to the second light-emitting unit may be k 1. Assuming that the target current of the first light emitting unit is n and the first preset value is m, the control module 104 distributes the current m to the first light emitting unit and distributes the current k1 × (n-m) to the second light emitting unit.

Further, in order to ensure the accuracy of the measurement of the biometric parameters, it is also possible to distribute the current m to the first light emitting unit and the current k1 (n-m) to the second light emitting unit at the first time, distribute the current k2 (n-m) to the first light emitting unit and the current m to the second light emitting unit at the second time, distribute the current m to the first light emitting unit and the current k1 (n-m) to the second light emitting unit at the third time, and so on.

Specifically, fig. 8 is another schematic distance diagram of the light-emitting unit and the photoelectric conversion module, as shown in fig. 8, for a certain wearable device, the wearable device includes a light-emitting unit LED3 and an LED4, wherein distances between the LEDs 3 and 4 and the photoelectric conversion module PD are different, and a distance between the LED3 and the photoelectric conversion module PD is smaller than a distance between the LED4 and the photoelectric conversion module PD. When the control module 104 distributes the current, it is assumed that at the first time, the control module 104 determines that the current of the light emitting unit LED3 is n, and the current n is greater than the first preset value m, and at this time, the control module may distribute the current m to the light emitting unit LED3 and distribute the current k1 × (n-m) to the light emitting unit LED 4.

Further, to ensure the accuracy of the measurement result, the control module 104 may allocate the current k2 (n-m) to the light emitting unit LED3 and the current m to the light emitting unit LED4 at the second time, and allocate the current m to the light emitting unit LED3 and the current k1 (n-m) to the light emitting unit LED4 at the third time, and so on.

It should be understood that after the current is distributed to the first light emitting unit and the second light emitting unit according to the above-mentioned shunt coefficient, the first light emitting unit and the second light emitting unit emit light together, and an absolute value of a difference between the current value received by the photoelectric conversion module 103 and the second preset value is smaller than a third preset value. Therefore, the accuracy of analyzing the signal by the photoelectric conversion module can be ensured, and the accuracy of measuring the biological characteristic parameters is improved.

In addition, after the control module 104 shunts the target current on the first light-emitting unit, the current values distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value, so that the voltage value on the LED module 101 is reduced, the voltage value on a pin of the PPG sensor can be ensured, and the PPG sensor can work normally.

In this embodiment, the shunt coefficient determined in the above manner not only can ensure that the current value on each light-emitting unit is smaller than the first preset value, but also can ensure that the measurement accuracy of the biometric parameter can approach the accuracy of the biometric parameter measured when a single light-emitting unit is lit when two light-emitting units are lit simultaneously.

Wherein, the accuracy of the measured biometric parameters when a single light emitting unit is lit and the accuracy of the measured biometric parameters when two light emitting units are lit simultaneously are shown in table 1 under different scenes.

TABLE 1

As shown in table 1, when two light emitting units are simultaneously lit, the accuracy of the measured biometric parameter can approach the accuracy of the biometric parameter measured when a single light emitting unit is lit.

In step 405, the control module 104 controls the first light emitting unit to emit light based on the target current to measure the biometric parameter of the target object.

In this step, if the control module 104 determines that the target current of the first light-emitting unit is smaller than the first preset value, it indicates that the voltage value of the first light-emitting unit is smaller, and at this time, the voltage value of the pin of the PPG sensor 102 is larger, so that the PPG sensor can be guaranteed to normally operate, and therefore, the target current of the first light-emitting unit does not need to be shunted. The control module 104 controls the first light emitting unit to continue emitting light according to the target current, so that the photoelectric conversion module can receive the light signal reflected by the skin, convert the light signal into an electric signal, and send the electric signal to the control module 104, and the control module 104 processes the electric signal, so as to obtain the biological characteristic parameter of the target object.

In the method for measuring biometric parameters provided in the embodiments of the present application, a control module determines a target current of a first light emitting unit currently lit in a light emitting module in a current period, and determines whether the target current of the first light emitting unit is greater than a first preset value, if it is determined that the target current of the first light emitting unit is greater than the first preset value, the control module may obtain a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to a second light emitting unit, and allocate currents to the first light emitting unit and the second light emitting unit in the light emitting module in the current period according to the shunt coefficient corresponding to the first light emitting unit and the shunt coefficient corresponding to the second light emitting unit, so as to adjust the target current of the first light emitting unit, and enable the first light emitting unit and the second light emitting unit to emit light according to the allocated currents, to measure a biometric parameter of the target object. The absolute value of the difference value between the current value received by the photoelectric conversion module and the second preset value is smaller than a third preset value, and the current values distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value. Because the currents distributed on the first light-emitting unit and the second light-emitting unit are less than or equal to the first preset value, the partial pressure on the light-emitting module is small, so that the voltage value on the pin of the PPG sensor can meet the preset voltage value, stable reference voltage is provided for the ADC in the PPG sensor, and the accuracy of the measurement result of the biological characteristic parameter is improved. In addition, when the target current on the first light-emitting unit is greater than the first preset value, the current can be shunted to the second light-emitting unit, so that the intensity of light emitted from the light-emitting module is not reduced, the absolute value of the difference between the current value received by the photoelectric conversion module 103 and the second preset value can be smaller than the third preset value, the photoelectric conversion module can normally analyze signals, and the accuracy of the measurement result of the biological characteristic parameter can be further ensured.

Fig. 9 is a schematic structural diagram of a measurement apparatus for measuring a biometric parameter according to an embodiment of the present application. The apparatus shown in fig. 9 may be used to perform the method described in any of the previous embodiments.

As shown in fig. 9, the apparatus 900 of the present embodiment may include: the light emitting module 901, the photoelectric conversion module 902 and the control module 903, wherein the light emitting module 901 includes at least two light emitting units 9011, and the at least two light emitting units 9011 are turned on in turn at different periods.

The control module 903 is configured to determine a target current of a currently lit first light-emitting unit in the light-emitting module 901 in a current period;

the control module 903 is further configured to determine whether a target current of the first light emitting unit is greater than a first preset value;

the control module 903 is further configured to obtain a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit when the target current on the first light emitting unit is greater than a first preset value;

the control module 903 is further configured to allocate currents to the first light emitting unit and the second light emitting unit in the light emitting module respectively in a current period according to a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit, so as to adjust a target current on the first light emitting unit, so that the first light emitting unit and the second light emitting unit emit light according to the allocated currents, so as to measure a biometric parameter of a target object, where an absolute value of a difference between the current received by the photoelectric conversion module and a second preset value is smaller than a third preset value, and the currents allocated to the first light emitting unit and the second light emitting unit are both smaller than or equal to the first preset value.

Optionally, the first preset value is a maximum current value capable of ensuring normal operation of a PPG sensor in the device; the second preset value and the third preset value are used for ensuring that the photoelectric conversion module can normally perform signal analysis.

Optionally, the control module 903 is specifically configured to:

acquiring current currently received by the photoelectric conversion module;

and determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module.

Optionally, the control module 903 is specifically configured to:

judging whether the adjustment times of the target current of the first light-emitting unit is greater than a fourth preset value or not;

if the adjustment times of the target current of the first light-emitting unit are not greater than the fourth preset value, judging whether the absolute value of the difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value;

and if the current is not less than the third preset value, determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module and the second preset value.

Optionally, the control module 903 is specifically configured to:

judging whether the current currently received by the photoelectric conversion module 902 is smaller than the second preset value;

if the current value is smaller than the second preset value, determining a target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a fifth preset value, wherein the fifth preset value is a maximum current value which can be borne by a photoplethysmography (PPG) sensor in the device;

if the current value is larger than the second preset value, determining the target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a sixth preset value, wherein the sixth preset value is a minimum current value which ensures that the PPG sensor can acquire signals.

Optionally, the control module 903 is specifically configured to:

determining an average value of the current of the first light-emitting unit and the fifth preset value as a target current of the first light-emitting unit.

Optionally, the control module 903 is specifically configured to:

determining an average value of the current of the first light-emitting unit and the sixth preset value as a target current of the first light-emitting unit.

Optionally, the control module 903 is further configured to:

if the number of times of adjusting the target current on the first light-emitting unit is greater than the fourth preset value, or the absolute value of the difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value, judging whether the current currently received by the photoelectric conversion module meets an ideal accuracy interval of an analog-to-digital converter (ADC) of a photoplethysmography (PPG) sensor in the device;

if the ideal interval of the accuracy of the ADC of the PPG sensor is not met, adjusting the current of the first light-emitting unit according to a preset mode, and determining the adjusted current as the target current of the first light-emitting unit;

and if the ideal interval of the accuracy of the ADC of the PPG sensor is met, determining the current of the first light-emitting unit as the target current of the first light-emitting unit.

Optionally, the control module 903 is specifically configured to:

distributing current a x m to the first light emitting unit, and distributing current b x (n-m) to the second light emitting unit, wherein a is a shunt coefficient corresponding to the first light emitting unit, b is a shunt coefficient corresponding to the second light emitting unit, n is a target current of the first light emitting unit, and m is the first preset value.

Optionally, a and b are both 1, and a distance between the first light emitting unit and the photoelectric conversion module is the same as a distance between the second light emitting unit and the photoelectric conversion module.

Optionally, a is 1, b is k, where a distance between the first light emitting unit and the photoelectric conversion module is smaller than a distance between the second light emitting unit and the photoelectric conversion module, and k is an integer greater than 1.

Optionally, the control module 903 is further configured to:

when the target current on the first light-emitting unit is not larger than the first preset value, the first light-emitting unit emits light based on the target current to measure the biological characteristic parameter of the target object.

The measurement apparatus for biometric parameters shown in the embodiments of the present application can implement the technical solution of the measurement method for biometric parameters shown in any of the embodiments, and the implementation principle and the beneficial effects thereof are similar, and are not described herein again.

It should be noted that the division of the modules of the above apparatus is only a logical division, and the actual implementation may be wholly or partially integrated into one physical entity, or may be physically separated. And these modules can be realized in the form of software called by processing element; or may be implemented entirely in hardware; and part of the modules can be realized in a mode of calling by the processing element through software, and part of the modules can be realized in a mode of hardware. For example, the control module may be a processing element separately installed, or may be implemented by being integrated into a chip of the measuring device of the biometric parameter, or may be stored in a memory of the measuring device of the biometric parameter in the form of a program, and a processing element of the measuring device of the biometric parameter may call and execute the function of the control module. Other modules are implemented similarly. In addition, all or part of the modules can be integrated together or can be independently realized. The processing element described herein may be an integrated circuit having signal processing capabilities. In implementation, each step of the above method or each module above may be implemented by an integrated logic circuit of hardware in a processor element or an instruction in the form of software.

These above modules may be one or more integrated circuits configured to implement the above methods, such as: one or more Application Specific Integrated Circuits (ASICs), or one or more microprocessors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs), among others. For another example, when the above module is implemented in the form of a processing element scheduler, the control module may be a general-purpose processor, such as a Central Processing Unit (CPU) or other processor capable of calling a program. As another example, these units may be integrated together and implemented in the form of a system-on-a-chip (SOC). .

Fig. 10 is a schematic structural diagram of an electronic device according to an embodiment of the present application. As shown in fig. 10, the electronic apparatus 1000 includes: LED module 1001, PD 1002, PPG sensor 1005, processor 1003 and memory 1004. The LED module comprises at least two light-emitting units, and the at least two light-emitting units are lighted in turn at different periods;

the memory 1004 is used for storing a program for implementing the above method embodiment, or each module of the embodiment shown in fig. 9, and the processor 1003 calls the program to execute the operation of the above method embodiment to implement each module shown in fig. 9.

Alternatively, part or all of the above modules may be implemented by being embedded in a chip of the electronic device in the form of an integrated circuit. And they may be implemented separately or integrated together. That is, the above units may be configured as one or more integrated circuits implementing the above methods, for example: one or more Application Specific Integrated Circuits (ASICs), or one or more microprocessors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs), among others.

The embodiment of the present application further provides a chip, where the chip includes at least one processor and a communication interface, where the communication interface and the at least one processor are interconnected by a line, and the at least one processor is configured to run a computer program or an instruction to execute the method for measuring a biometric parameter shown in any of the above embodiments, and an implementation principle and beneficial effects of the method are similar to an implementation principle and beneficial effects of the method for measuring a biometric parameter, and are not described herein again.

An embodiment of the present application further provides a computer-readable storage medium, where instructions are stored in the computer-readable storage medium, and when the instructions are executed on an electronic device, the electronic device is enabled to execute the method for measuring a biometric parameter shown in any of the above embodiments, and an implementation principle and beneficial effects of the method for measuring a biometric parameter are similar to those of the method for measuring a biometric parameter, and are not described herein again.

The embodiment of the present application further provides a computer program product, when the computer program product runs on an electronic device, the electronic device is enabled to execute the method for measuring a biometric parameter shown in any of the above embodiments, and the implementation principle and the beneficial effects of the method for measuring a biometric parameter are similar to those of the method for measuring a biometric parameter, and are not described herein again.

It should be understood that the processor in the embodiments of the present application may be a Central Processing Unit (CPU), and the processor may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It will also be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of Random Access Memory (RAM) are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct bus RAM (DR RAM).

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the modules is merely a logical division, and in actual implementation, there may be other divisions, for example, multiple modules or components may be combined or integrated into another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: u disk, removable hard disk, read only memory, random access memory, magnetic disk or optical disk, etc. for storing program codes.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method is characterized by being applied to electronic equipment, wherein the electronic equipment comprises a light-emitting module and a photoelectric conversion module, the light-emitting module comprises at least two light-emitting units, and the at least two light-emitting units are lighted in turn at different periods; the method comprises the following steps:

determining a target current on a first light-emitting unit which is currently lighted in a current period in the light-emitting module;

judging whether the target current on the first light-emitting unit is larger than a first preset value or not;

if the target current on the first light-emitting unit is larger than a first preset value, acquiring a shunt coefficient corresponding to the first light-emitting unit and a shunt coefficient corresponding to the second light-emitting unit;

distributing currents to the first light-emitting unit and the second light-emitting unit in the light-emitting module respectively in a current period according to the shunt coefficient corresponding to the first light-emitting unit and the shunt coefficient corresponding to the second light-emitting unit so as to adjust the target current on the first light-emitting unit, so that the first light-emitting unit and the second light-emitting unit emit light according to the distributed currents to measure the biological characteristic parameters of the target object, wherein the absolute value of the difference value between the current received by the photoelectric conversion module and the second preset value is smaller than a third preset value, and the currents distributed on the first light-emitting unit and the second light-emitting unit are both smaller than or equal to the first preset value.

2. The method according to claim 1, wherein the first preset value is a maximum current value capable of ensuring that a PPG sensor in the electronic device works normally; the second preset value and the third preset value are used for ensuring that the photoelectric conversion module can normally perform signal analysis.

3. The method according to claim 1 or 2, wherein the determining a target current on a first lighting unit currently lit in the lighting module in a current cycle comprises:

acquiring current currently received by the photoelectric conversion module;

4. The method of claim 3, wherein determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module comprises:

5. The method of claim 4, wherein determining the target current of the first light-emitting unit according to the current currently received by the photoelectric conversion module comprises:

judging whether the current currently received by the photoelectric conversion module is smaller than the second preset value;

if the current value is smaller than the second preset value, determining a target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a fifth preset value, wherein the fifth preset value is a maximum current value which can be borne by a photoplethysmography (PPG) sensor in the electronic equipment;

6. The method of claim 5, wherein determining the target current of the first light emitting unit according to the current of the first light emitting unit in the current period and a fifth preset value comprises:

7. The method of claim 5 or 6, wherein determining the target current of the first light-emitting unit according to the current of the first light-emitting unit in the current period and a sixth preset value comprises:

8. The method according to any one of claims 4-7, further comprising:

if the number of times of adjusting the target current on the first light emitting unit is greater than the fourth preset value, or the absolute value of the difference between the current currently received by the photoelectric conversion module and the second preset value is smaller than the third preset value, judging whether the current currently received by the photoelectric conversion module meets an ideal accuracy interval of an analog-to-digital converter (ADC) of a photoplethysmography (PPG) sensor in the electronic device;

9. The method according to any one of claims 1 to 8, wherein the distributing currents to the first light emitting unit and the second light emitting unit in the light emitting module in the current cycle according to the current splitting coefficient corresponding to the first light emitting unit and the current splitting coefficient corresponding to the second light emitting unit comprises:

distributing current a x m to the first light-emitting unit, and distributing current b x (n-m) to the second light-emitting unit, where a is a shunt coefficient corresponding to the first light-emitting unit, b is a shunt coefficient corresponding to the second light-emitting unit, n is a target current on the first light-emitting unit, and m is the first preset value.

10. The method according to claim 9, wherein a and b are both 1, and wherein a distance between the first light emitting unit and the photoelectric conversion module is the same as a distance between the second light emitting unit and the photoelectric conversion module.

11. The method according to claim 9, wherein a is 1 and b is k, wherein a distance between the first light emitting unit and the photoelectric conversion module is smaller than a distance between the second light emitting unit and the photoelectric conversion module, and k is an integer greater than 1.

12. The method according to any one of claims 1-11, further comprising:

if the target current on the first light-emitting unit is not larger than the first preset value, the first light-emitting unit emits light based on the target current to measure the biological characteristic parameter of the target object.

13. The device is characterized by comprising a light-emitting module and a photoelectric conversion module, wherein the light-emitting module comprises at least two light-emitting units which are lighted in turn at different periods; the device further comprises:

the control module is used for determining a target current on a first light-emitting unit which is currently lightened in the current period in the light-emitting module;

the control module is further used for judging whether the target current on the first light-emitting unit is larger than a first preset value;

the control module is further configured to obtain a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit when the target current on the first light emitting unit is greater than a first preset value;

the control module is further configured to allocate currents to the first light emitting unit and the second light emitting unit in the light emitting module respectively in a current period according to a shunt coefficient corresponding to the first light emitting unit and a shunt coefficient corresponding to the second light emitting unit, so as to adjust a target current on the first light emitting unit, so that the first light emitting unit and the second light emitting unit emit light according to the allocated currents, so as to measure a biometric parameter of a target object, wherein an absolute value of a difference between the current received by the photoelectric conversion module and a second preset value is smaller than a third preset value, and the currents allocated to the first light emitting unit and the second light emitting unit are both smaller than or equal to the first preset value.

14. The device according to claim 13, wherein the first preset value is a maximum current value capable of ensuring that a PPG sensor in the device works normally; the second preset value and the third preset value are used for ensuring that the photoelectric conversion module can normally perform signal analysis.

15. The apparatus according to claim 13 or 14, wherein the control module is specifically configured to:

acquiring current currently received by the photoelectric conversion module;

16. The apparatus of claim 15, wherein the control module is specifically configured to:

17. The apparatus of claim 16, wherein the control module is specifically configured to:

18. The apparatus of claim 17, wherein the control module is specifically configured to:

19. The apparatus according to claim 17 or 18, wherein the control module is specifically configured to:

20. The apparatus of any of claims 16-19, wherein the control module is further configured to:

21. The apparatus according to any one of claims 13-20, wherein the control module is specifically configured to:

22. The apparatus of claim 21, wherein a and b are both 1, and wherein a distance between the first light emitting unit and the photoelectric conversion module is the same as a distance between the second light emitting unit and the photoelectric conversion module.

23. The apparatus of claim 21, wherein a is 1 and b is k, wherein a distance between the first light emitting unit and the photoelectric conversion module is smaller than a distance between the second light emitting unit and the photoelectric conversion module, and k is an integer greater than 1.

24. The apparatus of any one of claims 13-23, wherein the control module is further configured to:

25. An electronic device, comprising: the LED module comprises at least two light-emitting units which are lighted in turn at different periods;

the memory is to store program instructions;

the processor is configured to invoke program instructions in the memory to perform the method of any of claims 1 to 12.

26. A chip comprising at least one processor and a communication interface, the communication interface and the at least one processor being interconnected by a line, the at least one processor being configured to execute a computer program or instructions to perform the method of any one of claims 1 to 12.

27. A computer-readable medium, characterized in that the computer-readable medium stores program code for computer execution, the program code comprising instructions for performing the method of any of claims 1 to 12.