WO2022126531A1

WO2022126531A1 - Blood oxygen saturation measurement apparatus and electronic device

Info

Publication number: WO2022126531A1
Application number: PCT/CN2020/137316
Authority: WO
Inventors: 杨小强
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2022-06-23

Abstract

A blood oxygen saturation measurement apparatus and an electronic device. A blood oxygen saturation measurement apparatus (210) is disposed below a display screen (220), and comprises: a photoelectric conversion unit (201) and a measurement unit (202). The photoelectric conversion unit (201) comprises a first photosensitive region (241), and is used for receiving, by means of the first photosensitive region (241), first finger reflected light having a first wavelength and second finger reflected light having a second wavelength from above the display screen (220), and generating pulse data on the basis of the first finger reflected light and the second finger reflected light. The measurement unit (202) is used for measuring finger blood oxygen saturation on the basis of the pulse data. The apparatus improves the accuracy of finger blood oxygen saturation measurement.

Description

Blood oxygen saturation detection device and electronic equipment

technical field

Embodiments of the present invention relate to the field of optoelectronic technology, and in particular, to a blood oxygen saturation detection device and electronic equipment.

Background technique

Blood oxygen saturation is the percentage of the capacity of oxyhemoglobin combined with oxygen in the blood to the total capacity of hemoglobin that can be combined, that is, the concentration of blood oxygen in the blood, which is an important physiological parameter of the respiratory cycle. Oxyhemoglobin means hemoglobin in the blood that is bound by oxygen. Reduced hemoglobin means hemoglobin in the blood that is not bound by oxygen.

Wearable devices such as smart bracelets and smart watches use infrared and red light alternately to collect pulse signals to calculate the above-mentioned blood oxygen saturation. However, in the prior art, when the wearable device is not fitted properly, the detection accuracy of blood oxygen saturation is poor.

SUMMARY OF THE INVENTION

In view of this, one of the technical problems solved by the embodiments of the present invention is to provide a blood oxygen saturation detection device and an electronic device.

According to a first aspect of the embodiments of the present invention, a blood oxygen saturation detection device is provided, which is arranged below a display screen, and the device includes: a photoelectric conversion unit, including a first photosensitive area. The photoelectric conversion unit receives reflected light from a first finger with a first wavelength and a second finger reflected light with a second wavelength from above the display screen through the first photosensitive area, and based on the reflection of the first finger The light and the second finger reflect the light to generate pulse data; the detection unit detects the blood oxygen saturation of the finger based on the pulse data.

According to a second aspect of the embodiments of the present invention, an electronic device is provided, the electronic device includes a display screen, and the blood oxygen saturation detection device according to the first aspect, which is disposed below the display screen.

In the solution of the embodiment of the present invention, since the upper surface of the display screen is attached by fingers, accurate pulse data can be generated based on the reflected light of the first finger and the reflected light of the second finger from above the display screen, thereby improving the The detection accuracy of finger blood oxygen saturation is improved.

Description of drawings

Hereinafter, some specific embodiments of the embodiments of the present invention will be described in detail by way of example and not limitation with reference to the accompanying drawings. The same reference numbers in the figures designate the same or similar parts or parts. It will be understood by those skilled in the art that the drawings are not necessarily to scale. In the attached picture:

1 is a schematic diagram of a typical example of a wearable device;

2A is a schematic block diagram of a blood oxygen saturation detection device according to an embodiment of the present invention;

Fig. 2B is a schematic side view of the electronic device including the blood oxygen saturation detection device of the embodiment of Fig. 2A;

2C is a schematic diagram of an arrangement of photosensitive regions of a photoelectric conversion unit according to another embodiment of the present invention;

3A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

3B is a schematic plan view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

4A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

4B is a schematic plan view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

5A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

5B is a schematic plan view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

6A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

6B is a schematic plan view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention;

7 is a schematic flowchart of a blood oxygen saturation detection method according to another embodiment of the present invention;

FIG. 8 is a schematic flowchart of a blood oxygen saturation detection method according to another embodiment of the present invention; and

FIG. 9 is a schematic block diagram of an electronic device according to another embodiment of the present invention.

Detailed ways

The specific implementation of the embodiments of the present invention is further described below with reference to the accompanying drawings of the embodiments of the present invention.

FIG. 1 is a schematic diagram of a typical example of a wearable device. Wearable devices such as smart bracelets and smart watches use infrared and red light alternately to collect pulse signals to calculate the above-mentioned blood oxygen saturation. As shown in Figure 1, the light-emitting device is a red light source and an infrared light source, both of which alternately emit a red light signal and an infrared light signal, irradiating the body part to be detected (for example, the wrist, etc.), and the photosensitive device collects the reflected signal accordingly. . Since the red light signal and the infrared light signal are alternately emitted, the pulse signals collected by the red light and the infrared light are not synchronized. At this time, if the fit between the wearable device and the part to be detected is not ideal, the pulse signal sensed by the photosensitive device will be affected. The interference effect of changing ambient light results in poor detection accuracy of the measured blood oxygen saturation.

FIG. 2A is a schematic block diagram of an apparatus for detecting blood oxygen saturation according to an embodiment of the present invention, and FIG. 2B is a schematic side view of an electronic device including the apparatus for detecting blood oxygen saturation in the embodiment of FIG. 2A .

As shown in FIG. 2A and FIG. 2B , the blood oxygen saturation detection device 210 is disposed below the display screen 220 , and the blood oxygen saturation detection device 210 includes a photoelectric conversion unit 201 and a detection unit 202 .

It should be understood that the display screen herein may be a display screen of an electronic device. Electronic equipment includes but is not limited to: mobile communication equipment: This type of equipment is characterized by having mobile communication functions, and its main goal is to provide voice and data communication. Such terminals include: smart phones (such as iPhone), multimedia phones, functional phones, and low-end phones, etc.; ultra-mobile personal computer equipment: such devices belong to the category of personal computers, with computing and processing functions, and generally with mobile Internet features. Such terminals include: PDAs, MIDs and UMPC devices, such as iPads; portable entertainment devices: such devices can display and play multimedia content. Such devices include: audio and video players (eg iPod), handheld game consoles, e-books, as well as smart toys and portable car navigation devices; other electronic devices with data interaction functions.

It should also be understood that the display screen herein may include, for example, an organic electroluminescent display (Organic Light-Emitting Display, OLED), an Active Matrix/Organic Light Emitting Diode (AMOLED) panel, or a liquid crystal display (Liquid Crystal Display, LCD) display. For an LCD display, a backlight module is provided below the display panel, and the backlight module can be subjected to aperture processing or other optical designs to obtain light transmission above the display screen.

It should also be understood that the blood oxygen saturation detection device 210 may perform blood oxygen saturation detection when an application program having a function such as heart rate detection is started. In the interface of the application program, the user may be prompted to place the finger on the area, for example, the finger pressing area, in a manner such as highlighting a specific partial area with a specific color. At least one of the light of the first wavelength or the light of the second wavelength may also be irradiated with respect to the finger placement area. Other backup light sources may be disposed below the display screen, for example, for irradiating at least one of the light of the first wavelength or the light of the second wavelength. The controller of the display controls the backup light source or the display screen to perform the above-mentioned irradiation operation when the display screen detects that the finger placement area is blocked so as to have a matching degree of fit. The controller of the display can also send a control signal to the blood oxygen saturation detection device when the display screen detects that the finger placement area is blocked so as to have a matching degree of fit, and the control signal instructs the blood oxygen saturation detection device to execute the photoelectric conversion unit. and processing of at least one of the detection units. For example, the photoelectric conversion unit may always be in an on state, and the controller of the display sends a control signal to the detection unit when the finger placement area is blocked.

The photoelectric conversion unit 201 includes a first photosensitive region 241 .

It should be understood that the photoelectric conversion unit may be constituted by a device such as a photodiode, eg, composed of a single photodiode or an array of photodiodes. The photosensitive area of the photoelectric conversion unit can be a plane or a curved surface. In a plan view, the photosensitive area of the photoelectric conversion unit can be formed into a circle, a rectangle, etc., and fit under the display screen of the electronic device. The first photosensitive region may form all or part of the photosensitive region of the photoelectric conversion unit. The first photosensitive area may match the shape of the above-mentioned finger placement area.

It should also be understood that the photosensitive area of the photoelectric conversion unit may further include a second photosensitive area for fingerprint identification. The first photosensitive area and the second photosensitive area may form all or part of the photosensitive area of the photoelectric conversion unit. The first photosensitive area and the second photosensitive area may be adjacent areas, so as to increase the utilization efficiency of the photosensitive area of the photoelectric conversion unit. The first photosensitive regions may be arranged as separate regions, for example, the first photosensitive regions may be arranged on both sides of the second photosensitive regions, in other words, the first photosensitive regions are separated by the second photosensitive regions. A plurality of first photosensitive regions and a plurality of second photosensitive regions may also be arranged at intervals.

The photoelectric conversion unit 201 receives the reflected light of the first finger with the first wavelength and the reflected light of the second finger with the second wavelength from above the display screen 220 through the first photosensitive area 241, and based on the reflected light of the first finger and the second finger Reflects light to generate pulse data.

It should be understood that the first wavelength is different from the second wavelength, and the first wavelength may be smaller than the second wavelength. Either of the first wavelength and the second wavelength may be visible light or invisible light. For example, the first wavelength may be in the red light band and the second wavelength may be in the infrared light band. In addition, the reflected light of the first finger can be formed by irradiating the first light source, and the reflected light of the second finger can be formed by illuminating the second light source. Accordingly, the first photosensitive regions may be arranged corresponding to the positions of the light sources.

The detection unit 202 detects the blood oxygen saturation of the finger based on the pulse data.

Optionally, as another example, the photoelectric conversion unit 201 further includes a first photosensitive region 242 . The photoelectric conversion unit 201 receives the reflected light from the third finger above the display screen 220 through the second photosensitive area 242 to perform fingerprint recognition. It should be understood that the wavelength of the light reflected by the third finger may be smaller than the wavelength of the red light band.

In this example, since the photoelectric conversion unit includes a first photosensitive area for generating pulse data and a second photosensitive area for fingerprint recognition, the reflected light from the first finger, the reflected light from the second finger, and the reflected light from the third finger are all From the top of the display screen, the utilization efficiency of the photosensitive area is improved, and the detection efficiency of the blood oxygen saturation detection device is improved.

In addition, a plurality of second light sources may be arranged on the periphery of the photoelectric conversion unit. In the photosensitive area of the photoelectric photosensitive unit, the first photosensitive area is arranged around the second photosensitive area to correspond to the positions of the plurality of second light sources. The light source may be a portion of the display screen (eg, a self-luminous display screen) corresponding to the first photosensitive area.

In one example, the detection unit can be arranged at other positions of the electronic device, for example, at the edge or corner of the display screen, between the display screen and the photoelectric conversion unit, so as to ensure the photosensitive distance between the photoelectric conversion unit and the display. In order to ensure the detection of photosensitivity while reducing the thickness of the electronic device.

In another example, the detection unit may be disposed below or on the side of the photoelectric conversion unit, and the detection unit is at least integrally packaged with the photoelectric conversion unit into a chip or a module.

In another example, the photoelectric conversion unit receives reflected light from a third finger above the display screen through the second photosensitive area, and generates fingerprint data based on the reflected light from the third finger. The apparatus further includes: a fingerprint identification unit, based on the fingerprint data, Perform fingerprint identification.

In another example, the detection unit and the fingerprint identification unit are both disposed below or on the side of the photoelectric conversion unit, wherein the photoelectric conversion unit, the detection unit and the fingerprint identification unit are integrally packaged into a chip or a module.

In another example, the reflected light of the third finger may be formed by illuminating the third light source. For example, the third light source and the first light source may be a light source formed by emitting light of the third wavelength and the first wavelength from the same part of the display screen, since multiple light sources are provided without increasing the space of the components.

Specifically, when a user can start an interface such as a blood oxygen detection application or other application with a blood oxygen detection function in an electronic device such as a mobile phone. The user can press the finger to the fingerprint sensitive area in the above interface. In one example, a software program can be used to control the lighting of the red light spot at the fingerprint photosensitive area above the display screen, and at the same time, the infrared LED under the screen is lighted. In another example, a first light source (eg, a red LED light) and a second light source (eg, an infrared LED light) may be alternately lit.

In one example, the first wavelength is in the red band (between 600 nm and 805 nm, eg, 660 nm), and the second wavelength is in the infrared band (greater than 850 nm, eg, 940 nm). Thereby, better penetration into physiological tissue is achieved, and sufficient signal is ensured. In addition, one of the red light band and the infrared light band achieves the same absorption coefficient for reduced hemoglobin and oxyhemoglobin, and the other wavelength of light forms a larger difference in the absorption coefficient of reduced hemoglobin and oxyhemoglobin , improving the detection sensitivity. In addition, the red light band and the infrared light band realize the color light with little change in the absorption coefficient after the wavelength deviation caused by the dispersion of the diode wavelength.

In another implementation manner of the present invention, the reflected light of the first finger is formed by illuminating the first light source, and the reflected light of the second finger is formed by illuminating the second light source. In another implementation manner of the present invention, the detection unit is specifically configured to: extract the pulse signal corresponding to the first wavelength and the pulse signal corresponding to the second wavelength based on the pulse data; calculate the pulse signal of the first wavelength and the second wavelength The AC-DC proportional relationship of the pulse signal, which indicates the ratio between the AC component of the signal and the DC component of the signal; the detection module detects the blood oxygen saturation of the finger according to the respective AC-DC proportional relationship.

Since the blood oxygen saturation is the percentage of the oxygen-bound oxyhemoglobin capacity in the blood to the total bindable hemoglobin capacity, the blood oxygen saturation of the finger is detected by the orthogonal proportional relationship, which improves the calculation efficiency.

Specifically, as an example, extracting the pulse signal corresponding to the first wavelength and the pulse signal corresponding to the second wavelength based on the pulse data may include: collecting the pulse data based on the preset frame rate to obtain the pulse signal corresponding to the first wavelength A pulse signal of one wavelength and a pulse signal corresponding to a second wavelength. As an example, calculating the respective AC/DC proportional relationship between the pulse signal of the first wavelength and the pulse signal of the second wavelength may include: determining the average signal of the pulse signal of the first wavelength and the pulse signal of the second wavelength based on the preset frame rate respectively feature; according to the average signal feature, calculate the respective AC/DC proportional relationship between the pulse signal of the first wavelength and the pulse signal of the second wavelength.

Further, for the collection of pulse data based on a preset frame rate, the fingerprint data can be continuously collected according to a fixed frame rate (for example, 10HZ˜1K). Determine the pulse signal of the first wavelength and the pulse signal of the second wavelength. Based on the average signal characteristics of the preset frame rate, the average optical signal amount of the red light and infrared bands in the sampled data can be calculated, for example, multiple consecutive frames within a period of time. The optical signal quantity of the finger pressing data presents a strong photoplethyamo Graphy (PPG) signal characteristic of the heart rate. According to the above signal characteristics, the blood oxygen saturation can be obtained by calculating the signal orthogonality ratio of the red light and the infrared band.

Specifically, blood oxygen saturation SPO2=HbO2/(HbO2+Hb)*100%, wherein HbO2 represents oxyhemoglobin; HB represents reduced hemoglobin. When light of a specific wavelength is incident, the light energy transmitted through human tissue can be divided into two parts: one part is constant, including non-pulsatile components such as muscles and bones; the other part is fluctuating components, which are generated by blood vessels with the heartbeat The contraction and relaxation mainly reflect the absorption of light by HB and HbO2 in the artery. Therefore, two light sources can be selected to obtain the AC and DC parts of the two substances in the blood to calculate the blood oxygen.

According to Rambo Beer's law, light transmitted into a medium will be absorbed by the medium, and the proportion of absorption is related to the wavelength of the incident light and the optical path of the light propagating in the medium. For example, after the monochromatic incident light passes through a uniform medium and the thickness of the medium is d, the transmitted light intensity I and the incident I0 light intensity have the following relationship.

I=I0*e ^-LC (1)

Among them, L represents the absorption coefficient of the medium to a specific light wavelength; C represents the concentration of the medium; d represents the optical path of the light passing through the medium.

Since the main components of hemoglobin in blood are reduced hemoglobin (Hb) and oxyhemoglobin (Hbo2), it can be considered that blood is a medium solution with a uniform concentration, that is, the incident light intensity through the human finger is I, and the light receiver receives If the reflected light intensity is I0, the following formula can be obtained.

I=I0*e ^-L0C0d0 *e ^-LHbCHbd *e ^-LHbO2CHbo2d (2)

Among them, L0, C0 and d0 respectively represent the sum of light absorption coefficients of static components such as venous blood, muscle and skin, the concentration of light-absorbing static components and the optical path penetrating the static components. LHb, CHb and d represent the light absorption coefficient of reduced hemoglobin in arterial blood, the concentration of reduced hemoglobin, and the arterial optical path, respectively. LHbo2, CHbo2 and d represent the light absorption coefficient of oxyhemoglobin in arterial blood, the concentration of oxyhemoglobin and the arterial optical path, respectively.

The pulsation of the human heart will cause arterial contraction and relaxation, so it can be assumed that the arterial light path during arterial contraction is d1, the received reflected light intensity is IDC, the arterial diastolic light path d2, and the received reflected light intensity is IDC-IAC ; and d2–d1=Δd. There is the following relationship:

IDC-IAC=IDC*e ^-LHbCHb△d *e ^{-LHbO2CHbo2△d} (3)

(4) can be deduced from (3):

ln[(IDC-IAC)/IDC]=-(LHbCHb+LHbo2CHb02)*△d (4)

Since the AC component is much smaller than the DC component, so

ln[(IDC-IAC)/IDC]≈IAC/IDC (5)

(6) can be deduced from (4) and (5):

IAC/IDC==-(LHbCHb+LHbo2CHb02)*△d (6)

Since Δd in the formula (6) is an unknown quantity, it is necessary to inject two different wavelengths of light into the formula 6, which can cancel Δd. Assume that the wavelengths of the two beams of light are λ1 and λ2 respectively:

λ1: Dλ1=IAC_λ1/IDC_λ1=-(LHb_λ1CHb+LHbo2_λ1CHb02)*△d(7)λ2: Dλ2=IAC_λ2/IDC_λ2=-(LHb_λ2CHb+LHbo2_λ2CHb02)*△d (8)

Since the two equations (7) and (8) are compared on both sides of the equal sign, (9) is obtained:

Dλ1/Dλ2=(LHb_λ1CHb+LHbo2_λ1CHb02)/(LHb_λ2CHb+LHbo2_λ2CHb02) (9)

Therefore, the oxygen saturation is calculated as follows:

SpO2=HbO2/(HbO2+Hb)*100% (10)

The blood oxygen saturation is derived from (9) and (10) as the ratio of the oxyhemoglobin concentration and the oxyhemoglobin concentration to the sum of the oxyhemoglobin concentrations:

SpO2=[LHb_λ2*(Dλ1/Dλ2)–LHb_λ1]/[(LHbO2_λ1–LHb_λ1)-(LHbO2_λ2–LHb_λ2)**(Dλ1/Dλ2)] (11)

When λ2 is selected as the band after 850 (refer to the wavelength of 940nm), then LHbO2_λ2≈LHb_λ2:

SpO2=[LHb_λ2*(Dλ1/Dλ2)–LHb_λ1]/(LHbO2_λ1–LHb_λ1) (12)

Among them, LHb_λ2, LHb_λ1 and LHbO2_λ1 are constants, so blood oxygen is only related to the A/D ratio of the two bands. Based on the measured PPG signals in the 660-band and 940-band, the DC and AC components were quantified to obtain the blood oxygen saturation.

In another implementation manner of the present invention, the reflected light of the first finger is formed by illuminating the first light source, and the reflected light of the second finger is formed by illuminating the second light source.

Since different light sources are beneficial to control the wavelength of emitted light, it is beneficial to realize finger reflection light of different wavelengths.

In another implementation manner of the present invention, the mixed finger reflected light of the first finger reflected light and the second finger reflected light is formed by simultaneously illuminating the finger with the first light source and the second light source. The first photosensitive area includes a first sub-photosensitive area and a second sub-photosensitive area, and a first filter for selecting a first wavelength and a second filter for selecting a second wavelength are respectively set above the first sub-photosensitive area and the second sub-photosensitive area device.

Since a first filter for selecting a first wavelength and a second filter for selecting a second wavelength are respectively disposed above the first sub-photosensitive area and the second sub-photosensitive area, the first filter and the second filter can obtain The light of the first wavelength and the light of the second wavelength are thus reliably separated for the light of different wavelengths. FIG. 2C shows an arrangement of photosensitive regions of a photoelectric conversion unit according to another embodiment of the present invention.

In another example, a third filter for selecting a third wavelength may be disposed above the second photosensitive region. The reflected light of the third finger may be formed by irradiating the third light source. The mixed finger reflected light of the first finger reflected light, the second finger reflected light and the third finger reflected light can be formed by simultaneously irradiating the finger with the first light source, the second light source and the third light source. The wavelengths of the first light source, the second light source and the third light source may be different from each other.

In another implementation manner of the present invention, the first light source is at least a part of the display screen, the display screen is a self-luminous display screen, and the second light source is arranged below the display screen.

Since a part of the self-luminous display screen is used as the first light source, the utilization efficiency of components is improved, in other words, the space for adding additional first light sources is saved.

In another implementation manner of the present invention, both the first light source and the second light source are arranged below the display screen.

Since both the first light source and the second light source are arranged below the display screen, it is advantageous to integrate the functions related to the blood oxygen saturation detection device into the electronic device.

Specifically, for the existing OLED or AMOLED, a red spot light source (605-700 nm) such as the self-illumination of the display screen can be used as the first light source to illuminate the finger, and multiple frames of pulse data can be continuously collected to realize red light (including but not Limited to 660nm band) pulse signal acquisition.

By adding a second light source such as an infrared light under the screen to illuminate the finger, and continuously collecting multiple frames of data, pulse signal acquisition in the infrared (including but not limited to 940nm band) band is achieved.

Since the fingerprint image sensor can directly receive red light and infrared light, it is easy to cause overexposure of the fingerprint image area in an outdoor strong light environment. Therefore, two areas are added to the fingerprint image sensor for transmitting the red light band (including but not limited to the 660nm band) and infrared band (including but not limited to 940nm band), and the remaining regions are used for visible light fingerprint imaging.

Without affecting the appearance of the mobile phone, the infrared band can be generated from the second light source such as infrared LED lights under the display screen through the infrared supplementary light under the screen, penetrate the display screen, enter the finger, and then pass through the finger and carry the pulse signal. , enter a specific area of the photoelectric conversion unit (for example, a fingerprint chip), and extract the pulse signal in the infrared band (including but not limited to the 940nm band).

The red light spot can be lit through the display screen to realize that the red light band (including but not limited to the 660nm band) penetrates the skin of the finger so as to carry the pulse signal without increasing the cost of hardware, which is reflected into the photoelectric conversion unit (for example, the fingerprint chip). In a specific area, the pulse signal in the red light band (including but not limited to the 660nm band) is extracted.

The first light source, such as the red spot of the display screen, and the second light source, such as the infrared LED light under the screen, can be illuminated at the same time to collect pulse signals of different frequency bands.

In another implementation manner of the present invention, the reflected light from the first finger and the reflected light from the second finger are formed by alternately irradiating the finger with the first light source and the second light source.

Since the reflected light from the first finger and the reflected light from the second finger are formed by alternately irradiating the finger with the first light source and the second light source, the same photosensitive area is used to realize the collection of different wavelength relationships.

Specifically, for OLED or AMOLED, the infrared light and red light under the screen are added to illuminate the finger alternately, and multiple frames of data are continuously collected to realize the collection of pulse signals in the infrared band (including but not limited to the 940nm band) and the red light. The collection of pulse signals in the optical waveband (including but not limited to the 660nm waveband).

In one example, a first photosensitive area may be reserved on the fingerprint sensor for detecting red light and infrared wavelength bands, and other areas, such as the second photosensitive area, may be used for fingerprint detection.

Without affecting the appearance of the mobile phone, the infrared band can be generated from the LED light below the screen through the infrared supplementary light under the screen, penetrate the screen, enter the finger, and then pass through the finger and carry the pulse signal to enter the photoelectric conversion unit (for example, fingerprint chip) to extract pulse signals in the infrared band (including but not limited to the 940nm band).

The red light source (including but not limited to the 660nm band) can penetrate the screen through the red light source (including but not limited to the 660nm band), such as the red LED light under the screen, and enter the finger to carry the pulse signal, which is then reflected into the photoelectric conversion unit (for example, fingerprints). A specific area of the chip) to extract the pulse signal in the red light band (refer to the 660nm band, but not limited to this band).

The first light source, such as the red LED light under the screen, and the second light source, such as the infrared LED light, can be alternately illuminated to collect pulse signals of different frequency bands

Since unlocking in scenes such as outdoor sunlight exposure will cause overexposure of the fingerprint image area, loss of image fingerprint lines, and difficulty in unlocking fingerprints caused by outdoor strong light, it will block the induction of part of the red light and infrared bands, so the second photosensitive area (for example, the photosensitive area of a fingerprint image sensor) needs to be avoided. A first photosensitive area is added to the fingerprint image sensor for transmitting light in the red band (including but not limited to 660nm band) and infrared band (including but not limited to 940nm band), and the rest of the area such as the second photosensitive area is used for fingerprints Imaging, not only can solve the difficult problem of outdoor strong light unlocking through fingerprint recognition in the second photosensitive area, but also realize blood oxygen detection through the first photosensitive area.

3A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention. The blood oxygen saturation detection device 340 is arranged below the display screen 320, and the blood oxygen saturation detection device 340 includes:

The photoelectric conversion unit includes a first photosensitive area 341 and a second photosensitive area 342, wherein the photoelectric conversion unit receives the reflected light from the first finger with the first wavelength and the second wavelength from above the display screen 320 through the first photosensitive area 341. The second finger reflects light from the second finger, and pulse data is generated based on the reflected light from the first finger and the reflected light from the second finger, wherein the photoelectric conversion unit receives the reflected light from the third finger above the display screen 320 through the second photosensitive area 342 to obtain pulse data. Perform fingerprint identification. The detection unit, based on the pulse data, detects the blood oxygen saturation of the finger.

For example, the first finger reflected light, the second finger reflected light and the third finger reflected light may come from finger 310 .

3B is a schematic plan view of an electronic device including a blood oxygen saturation detection apparatus according to another embodiment of the present invention. In the embodiment of the present invention, the reflected light of the first finger is formed by illuminating the first light source, and the reflected light of the second finger is formed by illuminating the second light source. The reflected light from the first finger and the reflected light from the second finger are formed by alternately irradiating the finger 310 with the first light source and the second light source. The first light source 321 is at least a part of the display screen 320 , for example, the display screen is a self-luminous display screen, and the second light source 330 is disposed below the display screen 320 . In another example, both the first light source and the second light source are disposed below the display screen 320 .

4A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention. The blood oxygen saturation detection device 440 is arranged below the display screen 420, and the blood oxygen saturation detection device 440 includes:

The photoelectric conversion unit includes a first photosensitive area 441 and a second photosensitive area 442, wherein the photoelectric conversion unit receives the reflected light from the first finger with the first wavelength and the second wavelength from above the display screen 420 through the first photosensitive area 441. The second finger reflects light from the second finger, and pulse data is generated based on the reflected light from the first finger and the reflected light from the second finger, wherein the photoelectric conversion unit receives the reflected light from the third finger above the display screen 420 through the second photosensitive area 442 to Perform fingerprint recognition; detection unit, based on pulse data, detects the blood oxygen saturation of the finger.

For example, the first finger reflected light, the second finger reflected light and the third finger reflected light may come from finger 410 .

4B is a schematic plan view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention. The reflected light of the first finger is formed by irradiating the first light source 421 , and the reflected light of the second finger is formed by irradiating the second light source 430 . In another example, the mixed finger-reflected light of the first finger-reflected light and the second finger-reflected light is formed by irradiating the finger 410 with the first light source 421 and the second light source 430 at the same time. The first photosensitive region includes a first sub-sensitivity region 4411 and a second sub-sensitivity region 4412. Above the first sub-sensitivity region 4411 and the second sub-sensitivity region 4412, a first filter for selecting the first wavelength and a second wavelength for selecting the the second filter. In one example, the first light source is at least a part of the display screen, the display screen is a self-luminous display screen, and the second light source is disposed below the display screen.

5A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention. The blood oxygen saturation detection device 540 is arranged below the display screen 520, and the blood oxygen saturation detection device 540 includes:

The photoelectric conversion unit includes a first photosensitive area 541 and a second photosensitive area 542, wherein the photoelectric conversion unit receives the reflected light from the first finger with the first wavelength and the second wavelength from above the display screen 520 through the first photosensitive area 541. The second finger reflects light from the second finger, and pulse data is generated based on the reflected light from the first finger and the reflected light from the second finger, wherein the photoelectric conversion unit receives the reflected light from the third finger above the display screen 520 through the second photosensitive area 542 to generate pulse data. Perform fingerprint recognition; detection unit, based on pulse data, detects the blood oxygen saturation of the finger.

For example, the first finger reflected light, the second finger reflected light and the third finger reflected light may come from finger 510 .

5B is a schematic plan view of an electronic device including a blood oxygen saturation detection apparatus according to another embodiment of the present invention. The reflected light of the first finger is formed by the irradiation of the first light source 531 , and the reflected light of the second finger is formed by the irradiation of the second light source 532 . The reflected light from the first finger and the reflected light from the second finger are formed by alternately irradiating the finger 510 with the first light source 531 and the second light source 532 . Both the first light source 531 and the second light source 532 are arranged below the display screen.

It should be understood that the arrangement positions of the first light source 531 and the second light source 532 may be arbitrary, for example, they may be arranged at the periphery of the finger pressing area or the photosensitive area. In one example, in a plan view, the second light source 532 (eg, shown as a solid circle) and the first light source 531 may be disposed on both sides of the finger pressing area or the photosensitive area. In another example, in a plan view, the second light source 532 (eg, as shown by an open circle) and the first light source 531 may be arranged on the same side of the finger pressing area or photosensitive area, or other peripheral locations.

6A is a schematic side view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention. The blood oxygen saturation detection device 640 is arranged below the display screen 620, and the blood oxygen saturation detection device 640 includes:

The photoelectric conversion unit includes a first photosensitive area 641 and a second photosensitive area 642 . The photoelectric conversion unit receives the reflected light of the first finger with the first wavelength and the reflected light of the second finger with the second wavelength from above the display screen through the first photosensitive area 641, and based on the reflected light of the first finger and the reflected light of the second finger , generates pulse data, wherein the photoelectric conversion unit receives the reflected light from the third finger above the display screen through the second photosensitive area 642 for fingerprint recognition; the detection unit detects the blood oxygen saturation of the finger based on the pulse data.

For example, the first finger reflected light, the second finger reflected light and the third finger reflected light may come from finger 610 .

6B is a schematic plan view of an electronic device including a blood oxygen saturation detection device according to another embodiment of the present invention. The reflected light of the first finger is formed by the irradiation of the first light source 631 , and the reflected light of the second finger is formed by the irradiation of the second light source 632 . The mixed finger reflected light of the first finger reflected light and the second finger reflected light is formed by simultaneously illuminating the finger 610 with the first light source and the second light source. The first photosensitive region includes a first sub-sensitivity region 6411 and a second sub-sensitivity region 6412. Above the first sub-sensitivity region 6411 and the second sub-sensitivity region 6412, a first filter for selecting the first wavelength and a second wavelength for selecting the the second filter. Both the first light source and the second light source are arranged below the display screen.

It should be understood that the arrangement positions of the first light source 631 and the second light source 632 may be arbitrary, for example, they may be arranged at the periphery of the finger pressing area or the photosensitive area. In one example, in a plan view, the second light source 632 (eg, shown as a solid circle) and the first light source 631 may be disposed on both sides of the finger pressing area or the photosensitive area. In another example, in a plan view, the second light source 632 (eg, as shown by an open circle) and the first light source 631 may be arranged on the same side of the finger pressing area or photosensitive area, or other peripheral locations.

FIG. 7 is a schematic flowchart of a blood oxygen saturation detection method according to another embodiment of the present invention. as the picture shows,

In step S701, the user activates a blood oxygen saturation detection function such as heart rate detection. Specifically, after the user chooses to activate the blood oxygen saturation detection function, the user's pressing position is increased in the interface of the application program.

In step S702, the user presses the pulse collection area. Specifically, the user can press the finger on the display screen according to the prompted pressing position. The pulse collection area may be the same as the fingerprint collection area, or may be different from the fingerprint collection area.

In step S703, the light spot in the fingerprint photosensitive area and the infrared light source under the screen are lit. Specifically, when the user presses the finger to the fingerprint photosensitive area, the light spot in the fingerprint photosensitive area and the infrared LED light are turned on immediately, and pulse data collection starts.

In step S704, optical fingerprint signals and/or images are continuously collected. Specifically, pulse signals such as heart rate PPG characteristic signals in the red and infrared bands are extracted from continuously collected optical fingerprint signals or image data.

In step S705, it is judged whether the number of captured frames is greater than N (preset frame number threshold), if yes, go to step S706; if not, go to step S707.

In step S706, it is judged whether the quality of the first wavelength signal and the second wavelength signal is stable, if yes, go to step S708, if no, go to step S707.

In step S707, it is judged whether the user is keeping pressing, if yes, go to step S704, if no, go to step S709.

In step S708, the blood oxygen saturation is calculated based on the pulse signal such as the heart rate PPG characteristic signal. Specifically, the current blood oxygen saturation of the tested person is obtained through the pulse signal in the red light band and the infrared band, and the ratio of the AC and DC components.

In step S709, processing of actions related to the user interface is performed.

FIG. 8 is a schematic flowchart of a blood oxygen saturation detection method according to another embodiment of the present invention.

In step S801, the user activates a blood oxygen saturation detection function such as heart rate detection. Specifically, after the user chooses to activate the blood oxygen saturation detection function such as heart rate detection, the user's pressing position is increased in the interface of the application program.

In step S802, the user presses the pulse collection area. Specifically, the user can press the finger on the display screen according to the prompted pressing position. The pulse collection area may be the same as the fingerprint collection area, or may be different from the fingerprint collection area.

In step S803, the light spot in the fingerprint photosensitive area and the infrared light source under the screen are lit. Specifically, when the user presses the finger to the fingerprint photosensitive area, the light spot in the fingerprint photosensitive area and the infrared LED light are turned on immediately, and pulse data collection starts.

In step S804, after the red light source is turned on to collect one frame of data, the red light source is turned off, and the infrared light source is turned on.

In step S805, after the infrared light source is turned on to collect one frame of data, the infrared light source is turned off, and the red light source is turned on.

In step S806, it is judged whether the number of captured frames is greater than N (preset frame number threshold), if yes, go to step S807; if not, go to step S808.

In step S807, it is judged whether the quality of the first wavelength signal and the second wavelength signal is stable, if yes, go to step S809, if no, go to step S808.

In step S808, it is determined whether the user is keeping pressing, if yes, go to step S805, if no, go to step S810.

In step S809, the blood oxygen saturation is calculated based on the pulse signal such as the heart rate PPG characteristic signal. Specifically, the current blood oxygen saturation of the tested person is obtained through the pulse signal in the red light and infrared bands, and the ratio of the AC and DC components.

In step S810, processing of actions related to the user interface is performed.

FIG. 9 is a schematic block diagram of an electronic device according to another embodiment of the present invention. As shown in FIG. 9 , the electronic device 910 includes a display screen 902 and a blood oxygen saturation detection device 901 , and the blood oxygen saturation detection device 901 is arranged below the display screen 902 .

The functions of each unit and each component of the blood oxygen saturation detection device 901 are the same as those of the blood oxygen saturation detection device 210 .

So far, specific embodiments of the present subject matter have been described. Other embodiments are within the scope of the appended claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. Additionally, the processes depicted in the figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In certain embodiments, multitasking and parallel processing may be advantageous.

In the 1990s, improvements in a technology could be clearly differentiated between improvements in hardware (eg, improvements to circuit structures such as diodes, transistors, switches, etc.) or improvements in software (improvements in method flow). However, with the development of technology, the improvement of many methods and processes today can be regarded as a direct improvement of the hardware circuit structure. Designers almost get the corresponding hardware circuit structure by programming the improved method flow into the hardware circuit. Therefore, it cannot be said that the improvement of a method flow cannot be realized by hardware entity modules. For example, a Programmable Logic Device (PLD) (such as a Field Programmable Gate Array (FPGA)) is an integrated circuit whose logic function is determined by user programming of the device. It is programmed by the designer to "integrate" a digital system on a PLD without having to ask the chip manufacturer to design and manufacture a dedicated integrated circuit chip. Moreover, today, instead of making integrated circuit chips by hand, this kind of programming is also mostly implemented using "logic compiler" software, which is similar to the software compiler used in program development and writing, and needs to be compiled before compiling. The original code also has to be written in a specific programming language, which is called Hardware Description Language (HDL), and there is not only one HDL, but many kinds, such as ABEL (Advanced Boolean Expression Language) , AHDL (Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, RHDL (Ruby Hardware Description Language), etc., currently the most commonly used The ones are VHDL (Very-High-Speed Integrated Circuit Hardware Description Language) and Verilog. It should also be clear to those skilled in the art that a hardware circuit for implementing the logic method process can be easily obtained by simply programming the method process in the above-mentioned several hardware description languages and programming it into the integrated circuit.

The controller may be implemented in any suitable manner, for example, the controller may take the form of eg a microprocessor or processor and a computer readable medium storing computer readable program code (eg software or firmware) executable by the (micro)processor , logic gates, switches, application specific integrated circuits (ASICs), programmable logic controllers and embedded microcontrollers, examples of controllers include but are not limited to the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20 and Silicon Labs C8051F320, the memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art also know that, in addition to implementing the controller in the form of pure computer-readable program code, the controller can be implemented as logic gates, switches, application-specific integrated circuits, programmable logic controllers and embedded devices by logically programming the method steps. The same function can be realized in the form of a microcontroller, etc. Therefore, such a controller can be regarded as a hardware component, and the devices included therein for realizing various functions can also be regarded as a structure within the hardware component. Or even, the means for implementing various functions can be regarded as both a software module implementing a method and a structure within a hardware component.

The systems, devices, modules or units described in the above embodiments may be specifically implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or A combination of any of these devices.

For the convenience of description, when describing the above device, the functions are divided into various units and described respectively. Of course, when implementing the present invention, the functions of each unit may be implemented in one or more software and/or hardware.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

Memory may include forms of non-persistent memory, random access memory (RAM) and/or non-volatile memory in computer readable media, such as read only memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer readable media includes both persistent and non-permanent, removable and non-removable media and can be implemented by any method or technology for storage of information. Information may be computer readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read only memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), Flash Memory or other memory technology, Compact Disc Read Only Memory (CD-ROM), Digital Versatile Disc (DVD) or other optical storage, Magnetic tape cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media, such as modulated data signals and carrier waves.

It should also be noted that the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device comprising a series of elements includes not only those elements, but also Other elements not expressly listed, or which are inherent to such a process, method, article of manufacture, or apparatus are also included. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in the process, method, article of manufacture, or device that includes the element.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The invention may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular transactions or implement particular abstract data types. The invention may also be practiced in distributed computing environments where transactions are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including storage devices.

The various embodiments in this specification are described in a progressive manner, and the same and similar parts between the various embodiments may be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, as for the system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and for related parts, please refer to the partial descriptions of the method embodiments.

The above descriptions are merely embodiments of the present invention, and are not intended to limit the present invention. Various modifications and variations of the present invention are possible for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

A blood oxygen saturation detection device, characterized in that it is arranged below a display screen, and the device comprises:

The photoelectric conversion unit includes a first photosensitive area, wherein the photoelectric conversion unit receives the reflected light from a first finger with a first wavelength and a second light with a second wavelength from above the display screen through the first photosensitive area the finger reflects light, and generates pulse data based on the first finger reflected light and the second finger reflected light,

The detection unit detects the blood oxygen saturation of the finger based on the pulse data.
The device according to claim 1, wherein the reflected light of the first finger is formed by illuminating a first light source, and the reflected light of the second finger is formed by illuminating a second light source.
The device according to claim 2, wherein the mixed finger reflected light of the first finger reflected light and the second finger reflected light is formed by simultaneously illuminating the finger with the first light source and the second light source,

Wherein, the first photosensitive region includes a first sub-sensing region and a second sub-sensing region, and a first filter for selecting the first wavelength is respectively provided above the first sub-sensing region and the second sub-sensing region. and a second filter that selects the second wavelength.
The device according to claim 2, wherein the reflected light from the first finger and the reflected light from the second finger are formed by alternately irradiating the finger with the first light source and the second light source.
The device according to claim 3 or 4, wherein the first light source is at least a part of the display screen, the display screen is a self-luminous display screen, and the second light source is arranged below the display screen.
The device according to claim 3 or 4, wherein the first light source and the second light source are both arranged below the display screen.
The device according to claim 1, wherein the detection unit is disposed below or on the side of the photoelectric conversion unit, and the photoelectric conversion unit and the detection unit are integrally packaged into a chip or a module.
The device according to claim 1, wherein the photoelectric conversion unit further comprises a second photosensitive area, and the photoelectric conversion unit receives reflected light from a third finger above the display screen through the second photosensitive area, and Based on the reflected light of the third finger, fingerprint data is generated, and the device further includes:

The fingerprint identification unit performs fingerprint identification based on the fingerprint data.
The device according to claim 8, wherein the detection unit and the fingerprint identification unit are both arranged below or on the side of the photoelectric conversion unit, wherein the photoelectric conversion unit, the detection unit and the fingerprint The identification unit is integrally packaged into a chip or a module.
The device according to claim 1, wherein the detection unit is specifically used for:

extracting a pulse signal corresponding to the first wavelength and a pulse signal corresponding to the second wavelength based on the pulse data;

calculating the respective AC/DC proportional relationships of the pulse signal of the first wavelength and the pulse signal of the second wavelength, the AC/DC proportional relationship indicating the ratio between the AC component of the signal and the DC component of the signal;

The detection module detects the blood oxygen saturation of the finger according to the respective AC/DC proportional relationships.
The device according to claim 10, wherein the detection unit is specifically used for:

Collecting the pulse data based on a preset frame rate to obtain a pulse signal corresponding to the first wavelength and a pulse signal corresponding to the second wavelength;

determining the pulse signal of the first wavelength and the pulse signal of the second wavelength respectively based on the average signal characteristics of the preset frame rate;

According to the characteristic of the average signal, the AC/DC proportional relationship between the pulse signal of the first wavelength and the pulse signal of the second wavelength is calculated.
The device according to any one of claims 1-11, wherein the first wavelength is in the red light band and the second wavelength is in the infrared light band.
The device according to claim 12, wherein the wavelength of light reflected by the third finger is smaller than the wavelength of the red light band.
An electronic device, comprising:

display screen;

The blood oxygen saturation detection device according to any one of claims 1-13, which is arranged below the display screen.