Physiological information sensing module

Abstract

This invention provides a physiological information sensing module, comprising: a substrate; at least one light-emitting element disposed on the substrate; and at least two photosensitive elements disposed on the substrate, and including at least one photodiode and a complementary metal-oxygen image sensor, wherein the at least one photodiode is configured for sensing heart rate and blood oxygen level, and wherein the complementary metal-oxygen image sensor is configured for sensing blood pressure level.

Description

Physiological information sensing module PHYSIOLOGICAL INFORMATION SENSING MODULE Technical Field

[0001] This work relates to physiological information sensing modules, and more particularly to a physiological information sensing module that can accurately sense heart rate, blood oxygen levels, and blood pressure levels. Prior Technology

[0002] With the widespread adoption of wearable optoelectronic sensing devices, an increasing number of various optoelectronic components are being integrated into small wearable devices, ranging from larger smartwatches and wristbands to smaller smart rings. The light source wavelengths used in wearable optoelectronic sensing devices can include green light, red light, infrared light, or combinations thereof; sensors can include photodiodes (PDs), complementary metal-oxide-semiconductor (CMOS) image sensors (CIS), or combinations thereof. The light source wavelengths and sensor types used to measure heart rate, blood pressure, blood oxygen, body temperature, and other targets that can be sensed through optoelectronic sensing technology vary. Therefore, in addition to arranging various components in a confined space, the noise caused by mutual interference must also be considered. Thus, reducing noise to improve the signal-to-noise ratio (SNR), increasing photoresponsibility (A / W) to improve sensing accuracy, appropriately adjusting the configuration to minimize module size, and improving the sensitivity of sensing elements to reduce power consumption are current requirements for wearable optoelectronic sensing devices.

[0003] Therefore, after observing the aforementioned deficiencies and needs, the creator of this work came into being. Summary of the Invention

[0004] To address the aforementioned drawbacks and in accordance with the purposes of this invention, as embodied and broadly described herein, a physiological information sensing module is provided, comprising: a substrate; at least one light-emitting element disposed on the substrate; and at least two photosensitive elements disposed on the substrate, and including at least one photodiode and a complementary metal-oxygen image sensor, wherein the at least one photodiode is configured for sensing heart rate and blood oxygen levels, and wherein the complementary metal-oxygen image sensor is configured for sensing blood pressure levels.

[0005] According to one embodiment of the present invention, each photodiode is connected to a corresponding metal-oxide-semiconductor field-effect transistor (MOSFET), and each photodiode and the corresponding MOSFET share a semiconductor base to form an integrated photodetector, wherein the semiconductor base is a P-type semiconductor base or an N-type semiconductor base.

[0006] According to one embodiment of the present invention, the at least one light-emitting element includes: at least one green light-emitting element for sensing heart rate and blood pressure; and at least one red light-emitting element or infrared light-emitting element for sensing blood oxygen level.

[0007] According to one embodiment of the present invention, the at least one photodiode includes: at least one first photodiode configured to sense green light for sensing heart rate and blood pressure values; and at least one second photodiode configured to sense red or infrared light for sensing blood oxygen values.

[0008] According to one embodiment of the present invention, each of the at least one first photodiode has a blue filter layer disposed thereon, and each of the at least one second photodiode has a red filter layer disposed thereon.

[0009] According to one embodiment of the present invention, each of the at least one photodiode has a microlens disposed thereon.

[0010] According to one embodiment of the present invention, each of the at least one light-emitting element and the at least one photodiode has a light-shielding layer surrounding its side surface and bottom surface.

[0011] According to one embodiment of the present invention, each of the at least one light-emitting element and the at least one photodiode has a sealing layer disposed between the at least one light-emitting element and the at least one photodiode and the light-shielding layer.

[0012] According to one embodiment of the present invention, it further includes: a microprocessor disposed on the substrate; and a memory disposed on the substrate.

[0013] According to one embodiment of the present invention, the memory stores an application program for photoplethysmography, which is used to calculate heart rate, blood oxygen level, and blood pressure value using photoelectric signals.

[0014] This invention, through the configuration of at least one light-emitting element, at least two photosensitive elements, and a light-shielding layer, can improve the signal-to-noise ratio, increase the accuracy of sensing, minimize the module size, increase the sensitivity of sensing elements, and reduce power consumption. It can be easily and directly applied to small-sized, lightweight wearable or portable physiological information sensing devices. Simple Explanation of the Diagram

[0015] Figure 1 is a perspective view of a physiological information sensing module according to an embodiment of the present invention. Figure 2 is a perspective view of a physiological information sensing module according to another embodiment of the present invention. Figure 3 is a cross-sectional view of the structure of the light-shielding layer in Figure 2. Implementation

[0016] The present invention will now be more fully explained below with reference to the accompanying drawings, which illustrate exemplary embodiments of the present invention. The advantages and features of the present invention, as well as its implementation methods, will become apparent from the exemplary embodiments described in more detail below with reference to the accompanying drawings. However, it should be noted that the present invention is not limited to the exemplary embodiments described below, but can be implemented in various forms or styles. Therefore, exemplary embodiments are provided only to disclose the present invention and to enable those skilled in the art to understand the present invention and its spirit. In the drawings, exemplary embodiments of the present invention are not limited to the specific instances provided herein and are exaggerated for clarity.

[0017] The terminology used herein is for illustrative purposes only and is not intended to limit the scope of the invention. Unless the context clearly indicates otherwise, the singular forms of the terms "a" and "the" as used herein are intended to include the plural forms as well. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. It should be understood that when an element is referred to as "connected" or "coupled" to another element, the element may be directly connected or coupled to the other element or there may be intermediate elements.

[0018] Similarly, it should be understood that when an element (e.g., a layer, region, or substrate) is said to be "on" another element, the element may be directly on the other element, or there may be intermediate elements. In contrast, the term "directly" implies the absence of intermediate elements. It should also be understood that when the terms "comprising" or "including" are used herein, they indicate the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0019] Furthermore, exemplary embodiments in the detailed description will be illustrated by cross-sectional views, which serve as idealized exemplary diagrams of the present inventive concept. Accordingly, the shape of the exemplary diagrams may be modified according to manufacturing techniques and / or tolerable errors. Therefore, exemplary embodiments of the present inventive concept are not limited to the specific shapes shown in the exemplary diagrams, but may include other shapes that may be produced according to the manufacturing process. The areas illustrated in the drawings have general characteristics and are used to illustrate specific shapes of elements. Therefore, this should not be considered as limiting the scope of the present inventive concept.

[0020] It should also be understood that although the terms "first," "second," "third," etc., may be used herein to describe various elements, these elements should not be limited to these terms. These terms are only used to distinguish the various elements. Therefore, a first element in some embodiments may be referred to as a second element in other embodiments, without departing from the teachings of this invention. Exemplary embodiments of the inventive concepts illustrated and described herein include their complementary counterparts. Throughout this specification, the same reference numerals or the same indicators denote the same elements.

[0021] Furthermore, exemplary embodiments are described herein with reference to sectional views and / or plan views, which are idealized illustrative diagrams. Therefore, deviations from the illustrated shapes are expected due to factors such as manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as limited to the shapes of the areas shown herein, but are intended to include shape deviations caused, for example, by manufacturing processes. Therefore, the areas shown in the figures are schematic and their shapes are not intended to illustrate the actual shapes of the areas of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0022] The photoelectric measurement method used in the physiological information sensing module of this invention is photoplethysmography (PPG). PPG is a non-invasive optical technology that uses emitted light (usually green or red light) to penetrate the skin and uses sensors to detect changes in blood volume in blood vessels caused by the contraction and relaxation of the heartbeat.

[0023] When a beam of light of a certain wavelength shines on the skin surface of the fingertip, the contraction and dilation of blood vessels due to the heartbeat affect the transmission (e.g., light passing through the fingertip in a transmissive PPG) or the reflection (e.g., light from near the wrist surface in a reflective PPG). When light passes through skin tissue (e.g., the skin tissue of the fingers, including subcutaneous tissue, microvascular tissue, etc.) and is then reflected and / or transmitted to the photosensitive element, the light intensity will attenuate and change over time because the blood volume and blood oxygen saturation in the microvessels change with the pulse. By analyzing the changes in the transmitted or reflected light signals using corresponding algorithms, physiological data such as pulse, blood pressure, and / or blood oxygen saturation can be obtained.

[0024] By illuminating the skin with light from a light-emitting diode (LED) and measuring the amount of light transmitted or reflected over time using a photodiode, a graph representing the volume change caused by pulse pressure can be obtained. Because blood flow to the skin can be regulated by various other physiological systems, PPG can also be used to monitor respiration, hypoxia, and other circulatory conditions.

[0025] To improve photoresponsivity (A / W) and accurately obtain PPG patterns, commonly used photodiodes increase their light-receiving area to enhance photocurrent. However, in smart wearable devices, especially in space-constrained smart rings, this approach means that multiple photodiodes cannot be used to reduce measurement inaccuracies caused by wearing position, and there is also insufficient space to accommodate other types of sensing elements. Therefore, this invention aims to reduce the size of photodiode components while maintaining high photoresponsivity to improve the space utilization of smart wearable devices, thereby enabling the installation of more sensing elements.

[0026] Please refer to Figure 1, which is a perspective view of the physiological information sensing module according to an embodiment of this invention.

[0027] As shown in Figure 1, according to an embodiment of the present invention, a physiological information sensing module is provided, comprising: a substrate 10; at least one light-emitting element 20a disposed on the substrate 10; at least two photosensitive elements disposed on the substrate 10, including at least one photodiode (PD) 20b1 and a complementary CMOS image sensor (CIS) 20b2; a microprocessor 28 disposed on the substrate 10; and a memory (not shown) disposed on the substrate 10, wherein the at least one photodiode 20b1 is configured for sensing heart rate and blood oxygen saturation, wherein the complementary CMOS image sensor 20b2 is configured for sensing blood pressure, and wherein the memory stores an application program or algorithm related to photoplethysmography for calculating heart rate, blood oxygen saturation, and blood pressure using photoelectric signals.

[0028] Compared to the photodiode 20b1, the complementary metal-oxygen image sensor 20b2 can record the change of light intensity over time, thereby obtaining a more accurate blood pressure value. Therefore, this invention sets up the complementary metal-oxygen image sensor 20b2 specifically for blood pressure value sensing to improve the accuracy of blood pressure values.

[0029] According to embodiments of this invention, the substrate 10 may be a printed circuit board (PCB) or a flexible printed circuit board (FPCB), but is not limited thereto. The light-emitting element 20a of this invention may be a light-emitting diode (LED), a laser diode (LD), or a combination thereof, but is not limited thereto.

[0030] Furthermore, the photodiode 20b1 of this invention can be connected to a MOSFET (Metal-O-Semiconductor Field-Effect Transistor) (not shown in the figure) and shares a semiconductor base with the MOSFET to form an integrated photodetector. The MOSFET in the integrated photodetector can act as a gain amplifier for the photodiode 20b1 to amplify the photoelectric signal generated by the photodiode 20b1. Under the same photoelectric signal output intensity, since the photoelectric signal of the photodiode 20b1 in the integrated photodetector can be amplified by the MOSFET, the size of the photodiode 20b1 in the integrated photodetector can be reduced to less than 10% of that of a typical single photodiode. This helps to minimize the physiological information sensing module of this invention, or enables the physiological information sensing module of this invention to install more components within a limited and confined module space. The semiconductor base shared by the metal-oxide-semiconductor (MOSFET) and photodiode 20b1 in the integrated photoelectric sensor can be a P-type or N-type semiconductor base. That is, the MOSFET in the integrated photoelectric sensor can be an NMOSFET or a PMOSFET, while the photodiode 20b1 can be a PN-type or a PIN-type. For example, the semiconductor base can be a P-type or N-type silicon (Si) or germanium (Ge) base.

[0031] To improve measurement accuracy, according to embodiments of this invention, different colors of light can be used. Specifically, the at least one light-emitting element 20a may include: at least one green light-emitting element for sensing heart rate and blood pressure; and at least one red light-emitting element or infrared light-emitting element for sensing blood oxygen levels. For example, in the case of a single photodiode 20b1 (or an integrated photosensor), time division multiplexing can be used to allow the photodiode 20b1 to alternately sense green light and red or infrared light at different time periods, thereby achieving the function of sensing heart rate and blood oxygen levels.

[0032] Furthermore, to further improve the accuracy of the measurement, according to the embodiments of this invention, the at least one photodiode 20b1 may include: at least one first photodiode configured to sense green light for sensing heart rate and blood pressure values; and at least one second photodiode configured to sense red or infrared light for sensing blood oxygen levels. That is, in the case of a plurality of photodiodes 20b1 (or integrated photosensitive sensors), spatial division multiplexing can be used to enable the plurality of photodiodes 20b1 to simultaneously sense green light and red or infrared light, thereby achieving the function of sensing heart rate and blood oxygen levels.

[0033] Furthermore, to further improve the measurement accuracy, according to this embodiment, each of the at least one first photodiode used for sensing green light may have a green filter layer (not shown) disposed on the corresponding first photodiode, and each of the at least one second photodiode used for sensing red or infrared light may have a red filter layer (not shown) disposed on the corresponding second photodiode. This improves the signal-to-noise ratio.

[0034] Furthermore, to increase the intensity of the sensed light, according to this embodiment, each of the at least one photodiode 20b1 may have a microlens (not shown) disposed on the corresponding photodiode 20b1. This further improves the signal-to-noise ratio.

[0035] Please refer to Figures 2 and 3. Figure 2 is a perspective view of a physiological information sensing module according to another embodiment of the present invention; and Figure 3 is a cross-sectional view of the structure of the light-shielding layer in Figure 2.

[0036] As shown in Figure 2, in order to prevent interference from noise light, according to the present invention, each of the at least one light-emitting element 20a and the at least one photodiode 20b1 has a light-shielding layer 24 surrounding the side surface and bottom surface of the corresponding light-emitting element 20a and the photodiode 20b1.

[0037] In detail, as shown in Figures 2-3, according to another embodiment of this invention, a sealing structure for a photoelectric element 20 (e.g., applicable to the light-emitting element 20a and photodiode 20b1 of this invention) is proposed, comprising: a photoelectric element 20 disposed on a substrate 10; an element sealing structure 22 covering the photoelectric element 20; and a light-shielding layer 24 covering the side and bottom surfaces of the element sealing structure 22. In other words, due to the configuration of the light-shielding layer 24, the light-emitting element 20a and photodiode 20b1 of this invention can only emit light or be photosensitive from above within a limited angle, thereby eliminating or reducing interference from noise light and improving the signal-to-noise ratio.

[0038] It should be noted that the present invention can provide a light-shielding layer 24 for the light-emitting element 20a and the photodiode 20b1, while the complementary metal-oxide-semiconductor image sensor 20b2 is used to sense two-dimensional light signals and is not suitable for the above-mentioned light-shielding layer 24 configuration, so no light-shielding layer 24 is provided around it.

[0039] According to an embodiment of the present invention, the method for fabricating the above-mentioned sealing structure may include the following steps: (1) forming an element sealing structure 22 to cover a photoelectric element 20 (e.g., a light-emitting element 20a and a photodiode 20b1 applicable to the present invention); (2) coating a light-shielding layer 24 to cover the element sealing structure 22; (3) bonding the photoelectric element 20 to a substrate 10; and (4) removing the light-shielding layer 24 from the top surface of the element sealing structure 22 to expose the top surface of the element sealing structure 22. Furthermore, the above-mentioned sealing structure may further include: a module sealing layer 30 disposed on the substrate 10, surrounding the photoelectric element 20, and / or filling between a plurality of photoelectric elements 20; and a planarization layer 40 disposed on the top surface of the module sealing layer 30 and the element sealing structure 22.

[0040] Finally, based on the above embodiments, this invention, through the configuration of at least one light-emitting element, at least two photosensitive elements, and a light-shielding layer, can achieve the effects of improving the signal-to-noise ratio, increasing the accuracy of sensing, minimizing the module size, increasing the sensitivity of the sensing element, and reducing energy consumption. It can be easily and directly applied to small-sized, lightweight wearable or portable physiological information sensing devices.

[0041] The above describes the implementation of this invention through specific embodiments. Those skilled in the art can easily understand other advantages and effects of this invention from the content disclosed in this specification.

[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention; any equivalent changes or modifications made without departing from the spirit disclosed in the present invention shall be covered within the scope of the following patent applications.

[0043] 10:Substrate 20: Optoelectronic components 20a: Light-emitting element 20b1: Photodiode 20b2: Complementary Metal-Oxide-Semiconductor Image Sensor 22: Component sealing structure 24: Light-shielding layer 28: Microprocessor 30: Module sealing layer 40: Flattening layer

Claims

1. A physiological information sensing module, comprising: a substrate; at least one light-emitting element disposed on the substrate; and at least two photosensitive elements disposed on the substrate, and including at least one photodiode and a complementary metal-oxide-semiconductor image sensor, wherein, The at least one photodiode is configured for sensing heart rate and blood oxygen levels, and the complementary metal-oxygen half-image sensor is configured for sensing blood pressure levels.

2. The physiological information sensing module as described in claim 1, wherein, Each photodiode is connected to a corresponding metal-oxide-semiconductor field-effect transistor (MOSFET). Each photodiode and the corresponding MOSFET share a semiconductor base to form an integrated photodetector. The semiconductor base is either a P-type semiconductor base or an N-type semiconductor base.

3. The physiological information sensing module as described in any one of claims 1 to 2, wherein, The at least one light-emitting element includes: at least one green light-emitting element for sensing heart rate and blood pressure values; and at least one red light-emitting element or infrared light-emitting element for sensing blood oxygen values.

4. The physiological information sensing module as described in claim 3, wherein, The at least one photodiode includes: at least one first photodiode configured to sense green light for sensing heart rate and blood pressure values; and at least one second photodiode configured to sense red or infrared light for sensing blood oxygen values.

5. The physiological information sensing module as described in claim 4, wherein, Each of the at least one first photodiode has a blue filter layer disposed thereon, and each of the at least one second photodiode has a red filter layer disposed thereon.

6. The physiological information sensing module as described in any one of claims 1 to 2, wherein, Each of the at least one photodiode has a microlens disposed thereon.

7. The physiological information sensing module as described in any one of claims 1 to 2, wherein, Each of the at least one light-emitting element and the at least one photodiode has a light-shielding layer surrounding its side surface and bottom surface.

8. The physiological information sensing module as described in claim 7, wherein, Each of the at least one light-emitting element and the at least one photodiode has a sealing layer disposed between the at least one light-emitting element and the at least one photodiode and the light-shielding layer.

9. The physiological information sensing module as described in any one of claims 1 to 2, further comprising: A microprocessor is mounted on this substrate; And a memory chip is disposed on the substrate.

10. The physiological information sensing module as described in claim 9, wherein, The memory stores an application program for photoplethysmography, which is used to calculate heart rate, blood oxygen levels, and blood pressure using photoelectric signals.

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