This application claims priority to Taiwan Patent Application No. 112141070 filed on Oct. 26, 2023, which is hereby incorporated by reference in its entirety.
The present invention relates to an optical biomedical measurement device, particularly to a non-invasive optical biomedical measurement device.
In recent years, smart wearable devices (e.g., smart watches, etc.) have become popular. They can be used as non-invasive optical biomedical measurement devices to provide users with various physiological information (e.g., heart rate, blood oxygen saturation, blood pressure, blood glucose, etc.).
Due to the prolonged wear of the device against the body and its exposure to sweat from the surface of human skin, these contact areas are likely to become breeding grounds for bacteria. As these contact areas rub against the human skin over time, these bacteria may enter the skin and cause infections such as abscesses or painful rashes.
Given this, how to enhance the antibacterial ability of wearable devices is an urgent issue for the industry to solve.
An objective of the present invention is to improve the antibacterial ability of an optical biomedical measurement device. The present invention achieves the effect of enhancing the antibacterial ability by improving the process of forming the antibacterial optical film to make the antibacterial optical film has a periodic nano-structure for increasing the surface area (i.e., reaction area) of the antibacterial optical film. Accordingly, compared with conventional wearable devices, the wearable device using the optical biomedical measurement device of the present invention can have higher antibacterial ability.
To achieve the above objective, the present invention discloses an optical biomedical measurement device which includes: a substrate, a light source disposed on the substrate, a photodiode sensor disposed on the substrate, laterally spaced from the light source, a plurality of light-blocking walls disposed vertically on the substrate, laterally located on both sides of the light source and on both sides of the photodiode sensor, a sealing layer covering the light source, the photodiode sensor, and the light-blocking walls, a cover plate bonded to the sealing layer, a plurality of light-absorption films vertically aligned with the light-blocking walls, disposed in a plurality of etching regions on a top surface of the cover plate, an optical filter film disposed on the cover plate and the light-absorption films, a plurality of nano-metal particles arranged on the optical filter film with a distance therebetween, and an antibacterial optical film covering the nano-metal particles and the optical filter film.
In an example, the nano-metal particles are a plurality of nano-silver particles.
In an example, a ratio of an area of the nano-silver particles to an area of the optical filter film is less than 10%.
In an example, the nano-silver particles have a particle diameter of less than 5 nanometers (nm).
In an example, the distance of the nano-silver particles from each other is 50 nm to 100 nm.
In an example, the nano-silver particles are formed by performing a thermal annealing process after forming a silver film on the optical filter film.
In an example, the thermal annealing process is performed at 300° C. to 500° C. for 60 minutes.
In an example, a thickness of the antibacterial optical film is greater than 5 nm.
In an example, the antibacterial optical film has a refractive index
of 1.5 to 2.5.
In an example, the antibacterial optical film is made of zinc sulfide material.
In an example, the light source is a light-emitting diode.
In an example, the optical filter film is formed by interleavedly stacking a plurality of titanium dioxide layers and a plurality of silicon dioxide layers.
After referring to the drawings and the detailed description of embodiments described later, those of ordinary skill in the art can understand other objectives of the present invention, as well as the technical means and implementations of the present invention.
In the following description, the present invention will be explained with reference to various embodiments thereof. These embodiments of the present invention are not intended to limit the present invention to any specific environment, application or particular method for implementations described in these embodiments. Therefore, the description of these embodiments is for illustrative purposes only and is not intended to limit the present invention. It shall be appreciated that, in the following embodiments and the attached drawings, partial elements not directly related to the present invention are omitted from the illustration, and dimensional proportions among individual elements and the numbers of each element in the accompanying drawings are provided only for ease of understanding but are not intended to limit the actual scale.
An embodiment of the present invention is shown in
The optical biomedical measurement device 100 includes a substrate 11, a light source 13, a photodiode (PD) sensor 15, a plurality of light-blocking walls 17, a sealing layer 19, a cover plate 21, a plurality of light-absorption film 23, an optical filter film 25, a plurality of nano-metal particles 27 and an antibacterial optical film 29.
The substrate 11 may be a ceramic circuit board, but is not limited thereto. The thickness of the substrate 11 may be 0.45 millimeters (mm), but is not limited thereto. The light source 13 is disposed on the substrate 11. The light source 13 may be a light-emitting diode, e.g., a light-emitting diode generating light with a wavelength of 700 nm to 2000 nm. In other embodiments, the light source 13 may be another light-emitting device generating light in a specific wavelength range.
The photodiode sensor 15 is also disposed on the substrate 11 and is laterally spaced apart from the light source 13. The photodiode sensor 15 may be an indium gallium arsenide (InGaAs) photodiode sensor whose light-sensing wavelength range is 900 nm to 1700 nm, but is not limited thereto. The light-blocking walls 17 (e.g., three light-blocking walls) are arranged vertically on the substrate 11 and are laterally located on both sides of the light source 13 and both sides of the photodiode sensor 15. The light-blocking walls 17 can ensure that the light emitted from the light source 13 is not directly received by the photodiode sensor 15 and can also prevent light leakage. For example, each light-blocking wall 17 can be made of epoxy resin, which has a matte black appearance after curing so that neither visible light nor invisible light can penetrate each light-blocking wall 17. The height of the light-blocking walls 17 may be 0.5 mm, but is not limited thereto.
The sealing layer 19 may be a transparent epoxy resin, which covers the light source 13, the photodiode sensor 15 and the light-blocking walls 17, and allows the cover plate 21 to be bonded to the sealing layer 19. The cover plate 21 may be made of glass material. The thickness of the cover plate 21 may be 0.4 mm, but is not limited thereto. The light-absorption films 23 are vertically aligned with the light-blocking walls 17 and are disposed in a plurality of etched areas on a top surface of the cover plate 21. The light-absorption films 23 are used to absorb unnecessary reflected light.
Specifically, the etched areas are first formed on the top surface of the cover plate 21 at positions directly aligned with the light-blocking walls 17 by an etching process, and then the light-absorption films 23 are formed in the etched areas. Each light-absorption film 23 may be formed by interleavedly stacking a plurality of chromium (Cr) layers and a plurality of silicon dioxide (SiO2) layers, and has the characteristics of low reflection and high absorption. The thickness of each light-absorption film 23 may be 500 nm to 1500 nm. The thickness of each light-absorption film 23 is preferably 960 nm.
The optical filter film 25 is disposed on the cover plate 21 and the light-absorption films 23 to allow light within a specific spectrum to penetrate and reflect light within other spectra. The thickness of the optical filter film 25 may be 4 micrometers (μm)−10 μm. The thickness of the optical filter film 25 is preferably 4 μm. For example, the optical filter film 25 may be formed by interleavedly stack a plurality of titanium dioxide layers and a plurality of silicon dioxide layers, and may be formed by a physical vapor deposition (PVD) method or achemical vapor deposition (CVD) method. The thickness of each titanium dioxide layer and each silicon dioxide layer can be determined based on the wavelength of light, that is, based on the spectrum of the light source 13.
The nano-metal particles 27 are arranged on the optical filter film 25 with a distance therebetween. As shown in
For example, the nano-metal particles 27 may be a plurality of nanosilver particles to further provide an antibacterial effect. The ratio of the area of the nano-silver particles to the area of the optical filter film 25 may be less than 10%. The nano-silver particles have a particle diameter of less than 5 nanometers (nm). The distance of the nano-silver particles from each other may be 50 nm to 100 nm. In an embodiment, the particle diameter of the nano-silver particles is 5 nm, the distance between them is 50 nm (i.e., the period is 50 nm), and the ratio of the area of the nano-silver particles to the area of the optical filter film 25 is 8%.
The antibacterial optical film 29 covers the nano-metal particles 27 and the optical filter film 25. The antibacterial optical film 29 is in contact with human skin when the optical biomedical measurement device 100 is in use. The antibacterial optical film 29 may be made of zinc sulfide (ZnS) material, but is not limited thereto. In addition, in practice, the thickness of the antibacterial optical film 29 may be greater than 5 nm, and the refractive index of the antibacterial optical film 29 may be 1.5 to 2.5, but is not limited thereto. In other words, the periodic nano-structure (i.e., the optical filter film 25 on which the nano-metal particles 27 are arranged) may be plated with a zinc sulfide layer having a thickness greater than 5 nm.
It should be noted that in the present invention, the cover plate 21 and the structure above it may be made into a module first. In other words, the present invention may first form the light-absorption films 23 in the etched areas of the cover plate 21, and then form the optical filter film 25 on the cover plate 21 and the light-absorption films 23. Then, the nano-metal particles 27 and the antibacterial optical film 29 are formed on the optical filter film 25 to produce the module. Finally, the module is bonded to the sealing layer 19 (i.e., the cover plate 21 is bonded to the sealing layer 19) to complete the optical biomedical measurement device 100 of the present invention. In an embodiment, the present invention may use a large cover plate, form the aforementioned structure thereon, and obtain multiple modules by cutting.
In summary, the present invention forms periodically arranged nano-metal particles on the optical filter film to make the antibacterial optical film formed later also have a periodic nano-structure. Accordingly, the present invention can effectively increase the surface area (i.e., reaction area) of the antibacterial optical film and thereby improve the antibacterial ability of the wearable device.
The above embodiments are used only to illustrate the implementations of the present invention and to explain the technical features of the present invention, and are not intended to limit the scope of the present invention. Any modifications or equivalent arrangements that can be easily accomplished by those skilled in this art are considered to fall within the scope of the present invention, and the scope of the present invention should be limited by the claims of the patent application.
Number | Date | Country | Kind |
---|---|---|---|
112141070 | Oct 2023 | TW | national |