An internal multi-coaxial light source compact integrated PPG sensor packaging module

Abstract

An internal multi-coaxial light source compact integrated PPG sensor packaging module, the overall device signal-to-noise ratio is low and the overall integration of the module is difficult to standardize due to the low light emission efficiency of the PPG module light source and the low PD light source receiving efficiency. In the present application, a first flip structure is formed between each red Micro LED chip array plate and its corresponding light emitting lens and small pit; a second flip structure is formed between each green Micro LED chip array plate and its corresponding light emitting lens and small pit; a third flip structure is formed between each infrared LED chip and its corresponding light emitting lens and small pit; a light receiving lens is arranged on the top of each large pit; and a fourth flip structure is formed between each light detection monomer and its corresponding light receiving lens and large pit.

Description

Technical Field

[0001] This invention specifically relates to a compact integrated PPG sensor packaging module with internal multi-coaxial light sources, belonging to the field of electronic packaging technology. Background Technology

[0002] Currently, with the development of terminal technology, terminal devices have become an integral part of people's work and life. As various health problems frequently emerge, users' demand for personal health management is gradually increasing. To meet these needs, most terminal devices can enable users to monitor their health in real time. For example, users can use wearable devices, such as smartwatches, to measure human characteristics such as heart rate, respiratory rate, or blood oxygen levels.

[0003] The terminal device is capable of various monitoring functions because it is equipped with a monitoring module based on photoplethysmography (PPG). The PPG module mainly consists of a light-emitting diode (LED) light source (typically red, infrared, or green LED) and a photodetector (PD). Its core principle is: the LED emits light of a specific wavelength to irradiate skin tissue. After the light signal is transmitted to the skin, some of the light signal is absorbed by blood or other human tissues, while some is scattered and reflected. A portion of the scattered and reflected light signal is received by the PD and converted into a time-invariant direct current (DC) signal and a time-varying alternating current (AC) signal. By extracting the AC signal from the measurement signal, blood flow characteristics and blood parameters can be obtained for relevant human feature analysis. The measurement accuracy and detection effect of the PPG module are affected by the ratio of the AC signal to the DC signal. In practice, the ratio of the AC signal to the DC signal is generally less than one-thousandth, and it is also affected by various noises. Therefore, it is necessary to increase the ratio of AC signal to DC signal and improve the signal-to-noise ratio (SNR) of the system to improve the accuracy of monitoring data. However, due to the large size of current LEDs or other existing traditional light sources, directly integrating them with detectors into modules would result in an overall module package size that cannot meet the miniaturization requirements of wearable devices and implantable medical devices. Therefore, it is necessary to improve the overall compactness and miniaturization of PPG modules. The process of achieving compact miniaturization of the entire device is urgently needed. However, the low light extraction efficiency of PPG module light sources and the low light source efficiency of PD receivers currently result in a low overall device SNR and difficulties in standardizing the overall integration of the module. Summary of the Invention

[0004] To address the aforementioned challenges, this invention provides a compact integrated PPG sensor packaging module with internal multi-coaxial light sources.

[0005] A compact integrated PPG sensor packaging module with internal multi-coaxial light sources includes a packaging substrate, a self-barrier carrier block, multiple photodetectors, multiple red Micro LED arrays, multiple green Micro LED arrays, multiple infrared LED chips, multiple light-emitting lenses, and multiple light-receiving lenses. The packaging substrate is horizontally positioned, and the self-barrier carrier block is horizontally positioned on the packaging substrate. The self-barrier carrier block is a cylindrical structure. Multiple large and small recesses are sequentially machined along its radial direction from the outside to the inside on the top surface of the self-barrier carrier block. The large recesses are evenly arranged along the circumference of the self-barrier carrier block, and the small recesses are also evenly arranged along the circumference of the self-barrier carrier block. Each large recess contains a corresponding photodetector. The multiple red Micro LED arrays, multiple green Micro LED arrays, and multiple infrared LED chips are disposed within the multiple small recesses. Each red Micro LED array is disposed within a small recess, and each green Micro LED chip... The LED array board is set in a small recess, and each infrared LED chip is set in a small recess. A light emitting lens is set on the top of each small recess. A first flip-chip structure is formed between each red Micro LED array board, its corresponding light emitting lens, and the small recess. A second flip-chip structure is formed between each green Micro LED array board, its corresponding light emitting lens, and the small recess. A third flip-chip structure is formed between each infrared LED chip, its corresponding light emitting lens, and the small recess. A light receiving lens is set on the top of each large recess. A fourth flip-chip structure is formed between each light detector, its corresponding light receiving lens, and the large recess.

[0006] As a preferred embodiment: the light emitting lens is a light receiving small lens, the bottom surface of the light emitting lens is a first plane, the top surface of the light emitting lens is a first concave surface that is recessed downward along the thickness direction of the light emitting lens, a plurality of first annular protrusions are processed on the first concave surface, the plurality of first annular protrusions are arranged coaxially from the inside to the outside, the top end of the first annular protrusion adjacent to the self-blocking carrier is a first annular protrusion end, and the first annular protrusion end is flush with the top surface of the self-blocking carrier.

[0007] As a preferred embodiment: the light receiving lens is a large light receiving lens, the top surface of the light receiving lens is a second plane, the second plane is flush with the top surface of the self-blocking carrier, the bottom surface of the light receiving lens is a second concave surface that is recessed upward along the thickness direction of the light receiving lens, a plurality of second annular protrusions are processed on the second concave surface, the plurality of second annular protrusions are arranged coaxially from the inside to the outside, the upper end of each second annular protrusion is fixedly connected to the second concave surface, the lower end of each second annular protrusion is a second annular protrusion, and the second annular protrusion is spaced apart from the top of the light detection unit.

[0008] As a preferred option, the large pit is a cylindrical pit or a fan-shaped pit.

[0009] As a preferred option: when the large pit is cylindrical, the number of cylindrical pits ranges from 6 to 12; when the large pit is fan-shaped, the number of fan-shaped pits ranges from 3 to 6.

[0010] As a preferred embodiment: each red Micro LED array panel includes multiple red Micro LED chips, which are arranged in a square matrix on the top surface of the packaging substrate, and each red Micro LED chip is electrically connected to the packaging substrate.

[0011] As a preferred embodiment: each green Micro LED array panel includes multiple green Micro LED chips, which are arranged in a square matrix on the top surface of the packaging substrate, and each of the multiple green Micro LED chips is electrically connected to the packaging substrate.

[0012] As a preferred embodiment, the number of multiple red Micro LED array panels, the number of multiple green Micro LED array panels, and the number of multiple infrared LED chips are equal, and the multiple red Micro LED array panels, the multiple green Micro LED array panels, and the multiple infrared LED chips are alternately arranged in multiple small pits along the circumferential direction of the self-barrier carrier.

[0013] As a preferred option, the red Micro LED chip, green Micro LED chip, infrared LED chip, and photodetector unit are all flip-chip chips.

[0014] A compact integrated PPG sensor packaging module with internal multi-coaxial light sources is characterized by comprising a packaging substrate, a self-barrier carrier, a ring silicon detector, multiple red Micro LED arrays, multiple green Micro LED arrays, multiple infrared LED chips, multiple light-emitting lenses, and multiple planar glass lenses. The packaging substrate is horizontally arranged, and the self-barrier carrier is horizontally arranged on the packaging substrate. The self-barrier carrier is a cylindrical structure. Multiple large and multiple small recesses are sequentially machined along its radial direction from the outside to the inside of the top surface of the self-barrier carrier. The large recesses are evenly arranged along the circumference of the self-barrier carrier, and the multiple small recesses are also evenly arranged along the circumference of the self-barrier carrier. The bottoms of the large recesses are interconnected. The ring silicon detector is located at the bottom of the large recesses. The multiple red Micro LED arrays, multiple green Micro LED arrays, and multiple infrared LED chips are located within the multiple small recesses. Each red Micro LED array is located within a small recess, and each green Micro LED chip is located within a small recess. The LED array board is set in a small recess, and each infrared LED chip is set in a small recess. A light emitting lens is set on the top of each small recess. A first flip-chip structure is formed between each red Micro LED array board, its corresponding light emitting lens, and the small recess. A second flip-chip structure is formed between each green Micro LED array board, its corresponding light emitting lens, and the small recess. A third flip-chip structure is formed between each infrared LED chip, its corresponding light emitting lens, and the small recess. A planar glass lens is set on the top of each large recess.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] This invention relates to a compact integrated PPG sensor packaging module with multiple coaxial light sources. This module integrates Micro LED chips and Fresnel lenses. Through the interaction of the packaging substrate, self-blocking carrier, multiple photodetector units, multiple red Micro LED arrays, multiple green Micro LED arrays, multiple infrared LED chips, multiple light-emitting lenses, and multiple light-receiving lenses, multiple uniform flip-chip and fourth flip-chip structures are formed. This creates a structure that interconnects flip-chip, upright, and substrate components, reducing the overall height of the PPG module. This results in a smaller overall module size while simultaneously improving the light emission efficiency of the light source. This provides a standardized approach for achieving high accuracy and compact integration in the final PPG module monitoring, making it suitable for widespread adoption. Attached Figure Description

[0017] Figure 1 This is a top view of the PPG sensor packaging module provided in the first specific embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the cross-sectional structure at point AA of the PPG sensor packaging module provided in the first specific embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram illustrating the working principle of the PPG sensor packaging module provided in the first specific embodiment of the present invention;

[0020] Figure 4 This is a three-dimensional structural diagram of the PPG sensor packaging module provided in a specific embodiment of the present invention;

[0021] Figure 5 This is a top view of the PPG sensor packaging module provided in the second specific embodiment of the present invention;

[0022] Figure 6 This is a schematic diagram of the cross-sectional structure at the BB section of the PPG sensor packaging module provided in the second specific embodiment of the present invention;

[0023] Figure 7 This is a schematic diagram illustrating the working principle of the PPG sensor packaging module provided in the second specific embodiment of the present invention;

[0024] Figure 8 This is a three-dimensional structural diagram of the PPG sensor packaging module provided in the second specific embodiment of the present invention.

[0025] In the figure, 1-packaging substrate; 2-self-barrier carrier; 2-1-large recess; 2-2-small recess; 3-photodetector unit; 4-red Micro LED array plate; 4-1-red Micro LED chip; 5-green Micro LED array plate; 5-1-green Micro LED chip; 6-infrared LED chip; 7-light emitting lens; 7-1-first plane; 7-2-first recessed surface; 7-3-first annular ridge; 8-light receiving lens; 8-1-second plane; 8-2-second recessed surface; 8-3-second annular ridge; 13-ring silicon detector; 14-planar glass lens. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Specific implementation method one: Combining Figures 1 to 4This embodiment describes a compact integrated PPG sensor packaging module with multiple coaxial light sources. The module includes a packaging substrate 1, a self-barrier carrier block 2, multiple photodetectors 3, multiple red Micro LED arrays 4, multiple green Micro LED arrays 5, multiple infrared LED chips 6, multiple light-emitting lenses 7, and multiple light-receiving lenses 8. The packaging substrate 1 is horizontally positioned, and the self-barrier carrier block 2 is horizontally positioned on the substrate 1. The self-barrier carrier block 2 is a cylindrical structure. The top surface of the self-barrier carrier block 2 has multiple large recesses 2-1 and multiple small recesses 2-2 processed sequentially from the outside to the inside along its radial direction. The large recesses 2-1 are evenly arranged along the circumference of the self-barrier carrier block 2, and the small recesses 2-2 are also evenly arranged along the circumference of the self-barrier carrier block 2. Each large recess 2-1 contains a corresponding photodetector 3. The multiple red Micro LED arrays 4, multiple green Micro LED arrays 5, and multiple infrared LED chips 6 are disposed within the multiple small recesses 2-2. Each red Micro LED... LED array panel 4 is disposed within a small recess 2-2, each green Micro LED array panel 5 is disposed within a small recess 2-2, each infrared LED chip 6 is disposed within a small recess 2-2, and a light-emitting lens 7 is disposed on the top of each small recess 2-2. The light-detecting unit 3 is a light-detecting plate disposed on the packaging substrate 1 and electrically connected to the packaging substrate 1 in a flip-chip configuration. It is used to receive light signals emitted by multiple red Micro LED array panels 4, multiple green Micro LED array panels 5, and multiple infrared LED chips 6. A first flip-chip structure is formed between each red Micro LED array panel 4, its corresponding light-emitting lens 7, and the small recess 2-2; each green Micro LED array panel 5... A second flip-chip structure is formed between the LED array board 5 and its corresponding light-emitting lens 7 and small pit 2-2. A third flip-chip structure is formed between each infrared LED chip 6 and its corresponding light-emitting lens 7 and small pit 2-2. A light-receiving lens 8 is correspondingly provided on the top of each large pit 2-1. A fourth flip-chip structure is formed between each light-detecting unit 3 and its corresponding light-receiving lens 8 and large pit 2-1.

[0028] Among them, the large pit 2-1 is a cylindrical pit, and the number of cylindrical pits ranges from 6 to 12.

[0029] The compact integrated PPG sensor packaging module with internal multi-coaxial light source in this invention directly uses the flip-chip process. The selected Micro LEDs and PDs adopt a flip-chip structure, avoiding the need for wire bonding between the two chips. Simultaneously, there is no need to reserve I / O pins on the packaging substrate 1. Multiple photodetector units 3, multiple red Micro LED arrays 4, multiple green Micro LED arrays 5, multiple infrared LED chips 6, multiple light emitting lenses 7, and multiple light receiving lenses 8 are directly electrically interconnected with the packaging substrate 1 through a self-blocking carrier block 2. This reduces the risk of gold wire breakage during transportation and installation, avoiding damage to the gold wires during the overall packaging and transportation of the PPG module, and increasing the reliability of the PPG module. Since the wire bonding process for the two chips is eliminated, the space required for gold wire bonding is saved, reducing the overall height of the PPG module and allowing for a smaller overall module size. When the overall height of the module is reduced, the overall thickness of the self-blocking carrier 2, which prevents crosstalk between light sources, is also reduced. As a result, the area of ​​the side of the hole in the self-blocking carrier 2 is reduced, and the degree to which the light emitted by the Micro LED chip is absorbed by the side of the hole in the self-blocking carrier 2 is also reduced, which improves the light output efficiency of the Micro LED and is beneficial to the continuous and stable detection process of the PPG signal.

[0030] In this embodiment, the self-barrier carrier 2 is disposed on the packaging substrate 1. Both are cylindrical structures with different thicknesses. The self-barrier carrier 2 is processed with multiple large pits 2-1 and multiple small pits 2-2. The multiple large pits 2-1 and multiple small pits 2-2 are spaced apart, each forming several packaging spaces to prevent mutual interference during optical signal transmission or reception. Each large pit 2-1 and each small pit 2-2 is a hole. The number and size of the holes are determined according to the optical transmitting module and the optical receiving module. Each module has at least one optical transmitting module packaging space and at least one optical signal receiving module packaging space. The optical transmitting module is disposed in the optical transmitting packaging space, and the optical receiving module is disposed in the optical signal receiving packaging space. The self-barrier carrier 2 is integrally formed by injection molding.

[0031] In this embodiment, the light emitting module consists of multiple red Micro LED array boards 4, multiple green Micro LED array boards 5, and multiple infrared LED chips 6 configured in a flip-chip configuration. The light signal receiving module, consisting of flip-chip photodiode PD chips, is also located within the light signal receiving package space of the self-blocking carrier block 2 to reduce interference and distortion.

[0032] In this embodiment, the photodetector unit 3 is a photodiode chip, which is also a photodetector board. Specifically, it is a square PD chip, which is directly attached to the packaging substrate 1 for electrical connection in a flip-chip manner. The PD chip collects the light signals reflected by blood vessels emitted by multiple red MicroLED arrays 4, multiple green MicroLED arrays 5 and multiple infrared LED chips 6.

[0033] Specific Implementation Method Two: This implementation method is a further limitation of Specific Implementation Method One. In this implementation method, the light emitting lens 7 is a light receiving small lens. Specifically, the light emitting lens 7 is a light emitting Fresnel lens. The bottom surface of the light emitting lens 7 is a first plane 7-1, and the top surface of the light emitting lens 7 is a first recessed surface 7-2 that is recessed downward along the thickness direction of the light emitting lens 7. Multiple first annular ridges 7-3 are processed on the first recessed surface 7-2. The multiple first annular ridges 7-3 are arranged coaxially from the inside to the outside. The top end of the first annular ridge 7-3 adjacent to the self-blocking carrier block 2 is a first annular protrusion end. The first annular protrusion end is flush with the top surface of the self-blocking carrier block 2.

[0034] Specific Implementation Method 3: This implementation method is a further limitation of Specific Implementation Method 1 or 2. In this implementation method, the light receiving lens 8 is a large light receiving lens, specifically a Fresnel lens. The top surface of the light receiving lens 8 is a second plane 8-1, which is flush with the top surface of the self-blocking carrier block 2. The bottom surface of the light receiving lens 8 is a second recessed surface 8-2 that is recessed upward along the thickness direction of the light receiving lens 8. Multiple second annular protrusions 8-3 are processed on the second recessed surface 8-2. The multiple second annular protrusions 8-3 are arranged coaxially from the inside to the outside. The upper end of each second annular protrusion 8-3 is fixedly connected to the second recessed surface 8-2, and the lower end of each second annular protrusion 8-3 is a second annular protrusion end. The second annular protrusion end is spaced apart from the top of the light detection unit 3.

[0035] In this embodiment, the light-emitting Fresnel lens and the light-receiving Fresnel lens use Fresnel lenses with focusing function to replace the planar lenses. They are arranged between multiple light-detecting units 3, multiple red Micro LED array boards 4, multiple green Micro LED array boards 5, and multiple infrared LED chips 6 to form an encapsulation space. The number of Fresnel lenses is determined according to the light-emitting module and the light-receiving module. Their diameter is matched with the diameter of the large recess 2-1 and the small recess 2-2 in the self-blocking carrier block 2. The Fresnel lenses are made of BK7 optical glass material.

[0036] In this embodiment, the use of light-emitting Fresnel lenses and light-receiving Fresnel lenses allows the first, second, third, and fourth flip-chip structures to form a compact integrated structure. This results in more uniform light emission from the MicroLED, illuminating a larger area of ​​the skin surface. Simultaneously, it enables the PD to receive more uniform light that has been reflected and refracted within the skin, significantly improving the accuracy of monitoring data. When the PPG packaging module of this invention is applied to electronic devices, especially smart wearable devices, it facilitates the miniaturization design of these devices, meeting users' demands for miniaturization while maintaining the accuracy of monitoring data. Therefore, this PPG module is suitable for various terminal devices, including but not limited to smartwatches.

[0037] Specific Implementation Method 4: This implementation method is a further limitation of Specific Implementation Method 1, 2 or 3. In this implementation method, each red Micro LED array plate 4 includes multiple red Micro LED chips 4-1. The multiple red Micro LED chips 4-1 are arranged in a square matrix on the top surface of the packaging substrate 1, and each red Micro LED chip 4-1 is electrically connected to the packaging substrate 1.

[0038] In this embodiment, each green Micro LED array board 5 includes multiple green Micro LED chips 5-1, which are arranged in a square matrix on the top surface of the packaging substrate 1. Each of the multiple green Micro LED chips 5-1 is electrically connected to the packaging substrate 1.

[0039] In this embodiment, the number of multiple red Micro LED array boards 4, the number of multiple green Micro LED array boards 5, and the number of multiple infrared LED chips 6 are equal. The multiple red Micro LED array boards 4, the multiple green Micro LED array boards 5, and the multiple infrared LED chips 6 are alternately arranged in multiple small pits 2-2 along the circumferential direction of the self-blocking carrier block 2.

[0040] In this embodiment, individual Micro LED chips are arranged in a 4×4 horizontal-vertical array to form a module that serves as the light source. These modules are positioned in corresponding small recesses 2-2 within the self-barrier carrier block 2 and are directly mounted on the encapsulation substrate 1 via flip-chip bonding, electrically connected to the substrate 1. The Micro LED chip module specifically includes a green Micro LED chip 5-1, a red Micro LED chip 4-1, and an infrared LED chip 6. The green Micro LED chip 5-1 has a peak wavelength of 520nm-550nm, the red Micro LED chip 4-1 has a peak wavelength of 650nm-680nm, and the infrared LED chip 6 has a peak wavelength of 930nm-950nm.

[0041] In this embodiment, the size of a single red Micro LED chip 4-1 or a single green Micro LED chip 5-1 is in the micrometer range, which is an order of magnitude smaller than that of traditional LEDs. This invention is more conducive to the standardized and compact arrangement of the entire PPG module, and the holes in the self-blocking carrier block 2 can also be smaller, increasing overall stability and facilitating the miniaturization of the PPG module. Micro LED chips also have advantages such as high brightness and low power consumption, improving the battery life of PPG modules used in terminal devices compared to traditional LED-based light sources.

[0042] In this embodiment, each of the red Micro LED chip 4-1, green Micro LED chip 5-1, infrared LED chip 6, and photodetector unit 3 is a flip-chip. A first flip-chip structure is formed between each red Micro LED array plate 4 and its corresponding light-emitting lens 7 and small pit 2-2; a second flip-chip structure is formed between each green Micro LED array plate 5 and its corresponding light-emitting lens 7 and small pit 2-2; a third flip-chip structure is formed between each infrared LED chip 6 and its corresponding light-emitting lens 7 and small pit 2-2; a light-receiving lens 8 is correspondingly provided on the top of each large pit 2-1; and a fourth flip-chip structure is formed between each photodetector unit 3 and its corresponding light-receiving lens 8 and large pit 2-1. This forms a multi-space flip-chip composite structure in various local areas and vertically, reducing the overall height of the PPG module while enabling the entire module to comprehensively improve the light emission efficiency of the light source.

[0043] In the specific application of this invention for heart rate and blood oxygen measurement, a green light signal from a Micro LED is used, while red light from a Micro LED and infrared light signals from an infrared LED are used for blood oxygen detection. The green Micro LED chip 5-1 has a peak wavelength of 520-550nm, the red Micro LED chip 4-1 has a peak wavelength of 650nm-680nm, and the infrared LED chip 6 has a peak wavelength of 930-950nm. The photodetector 3 receives wavelengths ranging from 400nm to 1100nm. Therefore, the photodetector 3 can receive light signals from the red Micro LED chip 4-1, the green Micro LED chip 5-1, and the infrared LED chip 6 to measure parameters such as heart rate and blood oxygen.

[0044] In the specific configuration of this invention, when eight photodetector units 3, two red Micro LED arrays 4, two green Micro LED arrays 5, and two infrared LED chips 6 are used together, the cooperation process of the above components can ensure that one green Micro LED chip 5-1 array, one red Micro LED chip 4-1 array, and one infrared LED chip 6 will form a heart rate and blood oxygen signal sampling module with the four photodetector units 3.

[0045] One working principle of the present invention is as follows:

[0046] During operation, the circuit driver module drives multiple red Micro LED array boards 4, multiple green Micro LED array boards 5, and multiple infrared LED chips 6 to emit light signals. The dispersed light emitted by the red Micro LED chip 4-1, green Micro LED chip 5-1, and infrared LED chip 6 reaches the smooth surface of the light-emitting lens 7. The Fresnel lens's focusing function converges and parallelizes the light, reducing absorption by the sidewalls of the small pits 2-2, allowing more light to become parallel and reach body parts such as the wrist or fingers. Some of the light signal is absorbed by the body tissue, while the rest is scattered and reflected. The scattered and reflected light reaches the smooth surface of the light-receiving lens 8 on the receiving plate. Similarly, the light passes through the light-emitting lens 7, converging and parallelizing the light, allowing more light to be received by the photodetector 3 and converted into an electrical signal. The back-end signal processing module receives the electrical signal output from the photodetector 3, amplifies and samples it to obtain the desired PPG signal. The PPG signal contains a slowly changing DC component (DC) and a pulsating AC component (AC) related to tissue structure and blood flow. The absorbance of non-blood tissues such as muscles and bones beneath the skin remains constant, and the absorbance of venous blood in blood tissue can also be considered relatively stable, primarily generating a DC component. Simultaneously, a relatively stable blood volume in arteries also generates a DC component. Therefore, it can be understood that the AC component extracted from sampling is mainly caused by the filling of arterial blood vessels. When blood vessels expand, the volume of arterial blood increases, resulting in more absorbed light signal and less scattered signal; when blood vessels recover, the volume of arterial blood returns to normal, the absorbed light signal decreases, and the scattered signal increases. Based on this periodic change in signal, we can determine human characteristics such as heart rate and blood oxygenation.

[0047] Specific Implementation Method Five: Combining Figures 4 to 8This embodiment describes a compact integrated PPG sensor packaging module with multiple coaxial light sources. The module includes a packaging substrate 1, a self-barrier carrier block 2, a ring silicon detector 13, multiple red Micro LED arrays 4, multiple green Micro LED arrays 5, multiple infrared LED chips 6, multiple light-emitting lenses 7, and multiple planar glass lenses 14. The packaging substrate 1 is horizontally positioned, and the self-barrier carrier block 2 is horizontally positioned on the packaging substrate 1. The self-barrier carrier block 2 is a cylindrical structure. Multiple large recesses 2-1 and multiple small recesses 2-2 are sequentially machined along its radial direction from the outside to the inside on the top surface of the self-barrier carrier block 2. The large recesses 2-1 are evenly arranged along the circumference of the self-barrier carrier block 2, and the multiple small recesses 2-2 are also evenly arranged along the circumference of the self-barrier carrier block 2. A ring silicon detector 13 is disposed within each of the large recesses 2-1. The multiple red Micro LED arrays 4, multiple green Micro LED arrays 5, and multiple infrared LED chips 6 are disposed within each of the multiple small recesses 2-2. Each red Micro LED... LED array panel 4 is disposed in a small recess 2-2, each green Micro LED array panel 5 is disposed in a small recess 2-2, each infrared LED chip 6 is disposed in a small recess 2-2, and a light emitting lens 7 is disposed on the top of each small recess 2-2. A first flip-chip structure is formed between each red Micro LED array panel 4, its corresponding light emitting lens 7, and the small recess 2-2. A second flip-chip structure is formed between each green Micro LED array panel 5, its corresponding light emitting lens 7, and the small recess 2-2. A third flip-chip structure is formed between each infrared LED chip 6, its corresponding light emitting lens 7, and the small recess 2-2. A planar glass lens 14 is disposed on the top of each large recess 2-1.

[0048] In this embodiment, the large recess 2-1 is a fan-shaped recess, and the number of fan-shaped recesses ranges from 3 to 6. The bottoms of multiple fan-shaped recesses are connected to form a mounting cavity, and a ring silicon detector 13 is disposed in the mounting cavity. The ring silicon detector 13 is a special ring silicon detector, which is an existing detector. The ring silicon detector 13 is arranged on the packaging substrate 1 along the circumferential direction and forms a monitoring module with the corresponding Micro LED chip, replacing the rectangular photodiode for light signal reception. The self-barrier carrier 2 is integrally formed by injection molding. The multiple small recesses 2-2 processed on the self-barrier carrier 2 provide mounting positions for multiple red Micro LED array plates 4, multiple green Micro LED array plates 5, and multiple infrared LED chips 6. The red Micro LED array plates 4 and green Micro LED array plates 5 are two types of Micro LED chips. The two types of Micro LED chips and the infrared LED chips 6 are arranged in an array in the small recesses 2-2 of the self-barrier carrier 2.

[0049] In this embodiment, the light-emitting lens 7 is a Fresnel lens, which is disposed on the top of the small pit 2-2 and the fan-shaped pit, and its shape is respectively matched with the shape of the small pit 2-2 and the fan-shaped pit; the planar glass lens 14 is disposed in the fan-shaped pit of the ring silicon detector 13, and its material is also BK7 optical glass.

[0050] In this embodiment, each chip is interconnected with the packaging substrate 1 in a flip-chip manner, which reduces the height of the overall PPG module and thus reduces the size of the entire module.

[0051] When the present invention is running, most of its energy consumption is due to lighting the light source. This application selects a Micro LED chip module as the light source, which can achieve lower power consumption than the traditional LED chips used in the prior art while meeting the requirements of detection brightness and irradiance, thereby reducing the power consumption of the entire PPG module.

[0052] This invention integrates a Fresnel lens to replace a conventional plane lens. By utilizing its functions of focusing, collimating, and parallelizing light, it improves the light output efficiency of Micro LED light sources and the light reception efficiency of photodiodes, thereby increasing the accuracy of blood oxygen and heart rate monitoring.

[0053] In this embodiment, each of the red Micro LED chip 4-1, green Micro LED chip 5-1, infrared LED chip 6, and ring silicon detector 13 is a flip-chip. A first flip-chip structure is formed between each red Micro LED array plate 4 and its corresponding light-emitting lens 7 and small pit 2-2; a second flip-chip structure is formed between each green Micro LED array plate 5 and its corresponding light-emitting lens 7 and small pit 2-2; and a third flip-chip structure is formed between each infrared LED chip 6 and its corresponding light-emitting lens 7 and small pit 2-2. This forms a multi-space flip-chip composite structure in various local areas and vertically, which reduces the overall height of the PPG module while enabling the entire module to comprehensively improve the light emission efficiency of the light source.

[0054] Specific Implementation Method Six: This implementation method is a further limitation of Specific Implementation Method Five. In this implementation method, the light emitting lens 7 is a light receiving small lens. The bottom surface of the light emitting lens 7 is a first plane 7-1, and the top surface of the light emitting lens 7 is a first recessed surface 7-2 that is recessed downward along the thickness direction of the light emitting lens 7. Multiple first annular protrusions 7-3 are processed on the first recessed surface 7-2. The multiple first annular protrusions 7-3 are arranged coaxially from the inside to the outside. The top end of the first annular protrusion 7-3 adjacent to the self-blocking carrier 2 is a first annular protrusion end. The first annular protrusion end and the top end of the self-blocking carrier 2 are on the same horizontal plane.

[0055] Specific Implementation Method Seven: This implementation method is a further limitation of Specific Implementation Method Five or Six. In this implementation method, each red Micro LED array plate 4 includes multiple red Micro LED chips 4-1. The multiple red Micro LED chips 4-1 are arranged in a square or rectangular matrix on the top surface of the packaging substrate 1. Each red Micro LED chip 4-1 is electrically connected to the packaging substrate 1.

[0056] In this embodiment, each green Micro LED array panel 5 includes multiple green Micro LED chips 5-1, which are arranged in a square matrix on the top surface of the encapsulation substrate 1. Each green Micro LED chip 5-1 is electrically connected to the encapsulation substrate 1. In this embodiment, the number of multiple red Micro LED array panels 4, the number of multiple green Micro LED array panels 5, and the number of multiple infrared LED chips 6 are equal. The multiple red Micro LED array panels 4, the multiple green Micro LED array panels 5, and the multiple infrared LED chips 6 are alternately arranged in multiple small recesses 2-2 along the circumferential direction of the self-barrier carrier block 2.

Claims

1. A compact integrated PPG sensor packaging module with internal multi-coaxial light source, characterized in that: The package includes a packaging substrate (1), a self-barrier carrier (2), multiple photodetectors (3), multiple red Micro LED arrays (4), multiple green Micro LED arrays (5), multiple infrared LED chips (6), multiple light-emitting lenses (7), and multiple light-receiving lenses (8). The packaging substrate (1) is horizontally arranged, and the self-barrier carrier (2) is horizontally arranged on the packaging substrate (1). The self-barrier carrier (2) is a cylindrical structure. The top surface of the self-barrier carrier (2) is processed with multiple large pits (2-1) and multiple small pits (2-2) from the outside to the inside along its radial direction. The multiple large pits (2-1) are evenly arranged along the circumference of the self-barrier carrier (2), and the multiple small pits (2-2) are evenly arranged along the circumference of the self-barrier carrier (2). Each large pit (2-1) is provided with a corresponding photodetector (3). The multiple red Micro LED arrays (4) and multiple green Micro LED arrays (5) are also provided. LED array board (5) and multiple infrared LED chips (6) are disposed in multiple small recesses (2-2). Each red Micro LED array board (4) is disposed in a small recess (2-2), each green Micro LED array board (5) is disposed in a small recess (2-2), and each infrared LED chip (6) is disposed in a small recess (2-2). A light emitting lens (7) is disposed on the top of each small recess (2-2). A first inverted structure is formed between each red Micro LED array board (4), its corresponding light emitting lens (7), and the small recess (2-2); each green Micro LED chip (6) is disposed in a small recess (2-2). A second flip structure is formed between the LED array board (5) and its corresponding light emitting lens (7) and small pit (2-2). A third flip structure is formed between each infrared LED chip (6) and its corresponding light emitting lens (7) and small pit (2-2). A light receiving lens (8) is correspondingly provided on the top of each large pit (2-1). A fourth flip structure is formed between each light detector unit (3) and its corresponding light receiving lens (8) and large pit (2-1).

2. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 1, characterized in that: The light emitting lens (7) is a light receiving small lens. The bottom surface of the light emitting lens (7) is a first plane (7-1), and the top surface of the light emitting lens (7) is a first recessed surface (7-2) that is recessed downward along the thickness direction of the light emitting lens (7). Multiple first annular protrusions (7-3) are processed on the first recessed surface (7-2). The multiple first annular protrusions (7-3) are arranged coaxially from the inside to the outside. The top end of the first annular protrusion (7-3) adjacent to the self-blocking carrier (2) is a first annular protrusion end. The first annular protrusion end is flush with the top surface of the self-blocking carrier (2).

3. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 2, characterized in that: The light receiving lens (8) is a large light receiving lens. The top surface of the light receiving lens (8) is a second plane (8-1). The second plane (8-1) is flush with the top surface of the self-blocking carrier (2). The bottom surface of the light receiving lens (8) is a second recessed surface (8-2) that is recessed upward along the thickness direction of the light receiving lens (8). Multiple second annular protrusions (8-3) are processed on the second recessed surface (8-2). The multiple second annular protrusions (8-3) are arranged coaxially from the inside to the outside. The upper end of each second annular protrusion (8-3) is fixedly connected to the second recessed surface (8-2). The lower end of each second annular protrusion (8-3) is a second annular protrusion. The second annular protrusion is spaced apart from the top of the light detection unit (3).

4. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 1, 2 or 3, characterized in that: Large pits (2-1) are cylindrical or fan-shaped pits.

5. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 4, characterized in that: When the large pit (2-1) is a cylindrical pit, the number of cylindrical pits ranges from 6 to 12; when the large pit (2-1) is a fan-shaped pit, the number of fan-shaped pits ranges from 3 to 6.

6. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 1, characterized in that: Each red Micro LED array panel (4) includes multiple red Micro LED chips (4-1), which are arranged in a square matrix on the top surface of the packaging substrate (1). Each red Micro LED chip (4-1) is electrically connected to the packaging substrate (1).

7. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 1 or 6, characterized in that: Each green Micro LED array panel (5) includes multiple green Micro LED chips (5-1). The multiple green Micro LED chips (5-1) are arranged in a square matrix on the top surface of the packaging substrate (1). Each multiple green Micro LED chip (5-1) is electrically connected to the packaging substrate (1).

8. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 7, characterized in that: The number of multiple red Micro LED array boards (4), the number of multiple green Micro LED array boards (5), and the number of multiple infrared LED chips (6) are equal. The multiple red Micro LED array boards (4), the multiple green Micro LED array boards (5), and the multiple infrared LED chips (6) are alternately arranged in multiple small pits (2-2) along the circumferential direction of the self-blocking carrier block (2).

9. The compact integrated PPG sensor packaging module with internal multi-coaxial light source according to claim 8, characterized in that: The red Micro LED chip (4-1), the green Micro LED chip (5-1), the infrared LED chip (6), and the photodetector unit (3) are all flip-chips.

10. A compact integrated PPG sensor packaging module with internal multi-coaxial light source, characterized in that: The package includes a packaging substrate (1), a self-barrier carrier (2), a ring silicon detector (13), multiple red Micro LED arrays (4), multiple green Micro LED arrays (5), multiple infrared LED chips (6), multiple light-emitting lenses (7), and multiple planar glass lenses (14). The packaging substrate (1) is horizontally arranged, and the self-barrier carrier (2) is horizontally arranged on the packaging substrate (1). The self-barrier carrier (2) is a cylindrical structure. The top surface of the self-barrier carrier (2) is processed with multiple large pits (2-1) and multiple small pits (2-2) from the outside to the inside along its radial direction. The multiple large pits (2-1) are evenly arranged along the circumference of the self-barrier carrier (2), and the multiple small pits (2-2) are evenly arranged along the circumference of the self-barrier carrier (2). The bottoms of the multiple large pits (2-1) are connected. The ring silicon detector (13) is located at the bottom of the multiple large pits (2-1). Multiple red Micro LED arrays (4), multiple green Micro LED arrays (5), multiple infrared LED chips (6), multiple light-emitting lenses (7), and multiple planar glass lenses (14) are connected. LED array board (4), multiple green Micro LED array boards (5) and multiple infrared LED chips (6) are arranged in multiple small pits (2-2). Each red Micro LED array board (4) is arranged in a small pit (2-2), each green Micro LED array board (5) is arranged in a small pit (2-2), and each infrared LED chip (6) is arranged in a small pit (2-2). A light emitting lens (7) is arranged on the top of each small pit (2-2). A first flip structure is formed between each red Micro LED array board (4), its corresponding light emitting lens (7) and the small pit (2-2). A second flip structure is formed between each green Micro LED array board (5), its corresponding light emitting lens (7) and the small pit (2-2). A third flip structure is formed between each infrared LED chip (6), its corresponding light emitting lens (7) and the small pit (2-2). A planar glass lens (14) is arranged on the top of each large pit (2-1).

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