TWI869100B - Deformable MHz Optical Mirror - Google Patents

Abstract

The present invention relates to a deformable megahertz optical reflector, which includes a metal woven mesh. The metal woven mesh has multiple longitudes and multiple latitudes, and the metal woven mesh can be bent into a hollow tube with a large area and a large angle. The multiple longitudes and multiple latitudes of the metal woven mesh are interwoven in an up-and-down manner, and the metal woven mesh in the hollow tube shape can transmit megahertz electromagnetic waves inside the hollow tube by optical mirror reflection.

Description

Deformable MHz optical mirror

The present invention relates to an optical reflector, and more specifically, to a deformable megahertz optical reflector.

Existing optical reflectors can be mainly divided into three categories: metal plane reflectors, multi-layer thin film medium plane reflectors and metal periodic microstructure plane reflectors.

Among them, the metal plane reflector achieves the reflection effect by using the megahertz electromagnetic wave frequency lower than the plasma frequency of the metal plane (usually in the near-infrared and visible light frequency range). Regarding the thickness of the metal film on the metal plane, the metal thickness must be higher than the skin depth of the electromagnetic wave. When the wavelength of the electromagnetic wave increases or the frequency decreases, the corresponding skin depth increases. For the thick surface metal film, it is easy to fall off due to the deformation factors of the substrate (such as elongation and distortion). In addition, the metal plane must also be flat and cannot have a rough surface of the wavelength level in order to achieve a high reflection effect. Therefore, for megahertz electromagnetic waves operating at millimeter or sub-millimeter wavelengths, metal plane reflectors are not suitable for soft substrates or soft substrates with multiple holes.

The multi-layer thin film dielectric plane reflector uses the Bragg structure principle to allow each layer of dielectric film to penetrate and reflect the megahertz electromagnetic wave with an appropriate thickness and refractive index. Among them, the thickness of the dielectric film is about one-fourth of the wavelength of the operating electromagnetic wave. Under this thickness and refractive index matching condition, a constructive interference reflection phenomenon can be formed at a specific megahertz electromagnetic wave frequency. For the purpose of high reflectivity, the number of layers of the dielectric film used must be sufficient, so for megahertz electromagnetic waves operating at millimeter or sub-millimeter wavelengths, its overall thickness is very large. Since the dielectric itself has electromagnetic wave absorption loss, when the total dielectric thickness is too large, the material's loss performance for megahertz waves will result in very low reflectivity.

In addition, metal periodic microstructure plane reflectors use the thickness of the air layer of the substrate to control the mirror reflection and achieve the highest reflectivity. However, the range of tolerance of the thickness of the air layer of the mirror reflection is extremely low. Therefore, large-area mirror reflection is not easy to operate in applications with bending and deformation conditions.

In view of this, how to provide a megahertz optical reflector with advantages such as low thickness, deformability and multi-hole structure is an urgent problem to be solved in this industry.

In order to solve the above-mentioned shortcomings of the existing technology, the main purpose of the present invention is to provide a deformable megahertz optical reflector, which includes a metal woven mesh. The metal woven mesh has multiple longitudes and multiple latitudes, and the metal woven mesh can be bent into a hollow tube with a large area and a large angle. Among them, the multiple longitudes and multiple latitudes of the metal woven mesh are interwoven in an up-and-down manner, and the metal woven mesh in the shape of a hollow tube can transmit megahertz electromagnetic waves inside the hollow tube by optical mirror reflection.

To achieve the above-mentioned purpose, the deformable megahertz optical reflector of the present invention has a plurality of warps and latitudes of the metal woven mesh that can form an equilateral hole width, and each has a metal wire diameter and a metal wire bending angle. The equilateral hole width is the distance between two adjacent warps or two adjacent latitudes, the metal wire diameter is a straight line of each warp or each latitude, and the metal wire bending angle is the bending angle when each warp and each latitude overlap each other to form an equilateral hole width.

To achieve the above-mentioned purpose, the deformable MHz optical reflector of the present invention has an equilateral hole width between 0.070 and 0.280 mm, a metal wire diameter between 0.030 and 0.130 mm, and a metal wire bending angle between 36 and 50 degrees.

In order to achieve the above-mentioned purpose, the thickness of the pure metal surface layer of each warp and each latitude of the metal woven mesh of the deformable megahertz optical reflector of the present invention is greater than 200 nanometers (nm).

To achieve the above-mentioned purpose, in the deformable megahertz optical reflector of the present invention, the frequency of megahertz electromagnetic waves is between 0.1 and 1.5 terahertz (THz).

To achieve the above-mentioned purpose, in the deformable megahertz optical reflector of the present invention, the metal braided mesh in the shape of a hollow tube has a hollow tube length and a hollow tube inner diameter, the hollow tube length is 25 cm, and the hollow tube inner diameter is 8 mm.

To achieve the above-mentioned purpose, the deformable megahertz optical reflector of the present invention further comprises a sleeve, which is arranged on the outer side of the metal woven mesh to cover and fix the metal woven mesh in the shape of a hollow tube.

In order to achieve the above-mentioned purpose, the surface of each warp and each latitude of the metal woven mesh of the deformable megahertz optical reflector of the present invention may have an adsorbent, and the adsorbent is used to adsorb specific molecules.

100: Deformable MHz optical reflector

200: Metal woven mesh

210: Warp

220: Latitude

300: Casing

A: Equilateral hole width

D:Metal wire diameter

θ: Metal wire bending angle

L: Hollow tube length

R: Hollow tube inner diameter

Figure 1 is a schematic diagram of the deformable megahertz optical reflector of the present invention.

Figure 2 is a schematic diagram of the metal woven mesh of the deformable megahertz optical reflector of the present invention.

Figure 3 is a top view of a unit body of the metal woven mesh periodic structure of the deformable megahertz optical reflector of the present invention.

Figure 4 is a three-dimensional side cross-sectional view of a unit body of the metal woven mesh periodic structure of the deformable megahertz optical reflector of the present invention.

Figure 5 is a schematic diagram of the deformable megahertz optical reflector of the present invention after being set in a sleeve.

FIG6 is a cross-sectional view of the end face of the deformable MHz optical reflector in FIG5 .

Figure 7 is a schematic diagram of another embodiment of the deformable megahertz optical reflector of the present invention.

The present invention is described in detail as follows with the accompanying drawings and in the form of an embodiment. The drawings used in the text are only for illustration and auxiliary description, and may not be the actual proportion and precise configuration after the implementation of the present invention. Therefore, the proportion and configuration of the attached drawings should not limit the patent scope of the present invention in actual implementation.

Please refer to Figures 1 and 2. A deformable megahertz optical reflector 100 of the present invention includes a metal woven mesh 200. The metal woven mesh 200 has a plurality of warps 210 and a plurality of latitudes 220, and the metal woven mesh 200 is preferably bendable into a hollow tube. As shown in Figures 2 and 3, the plurality of warps 210 and the plurality of latitudes 220 of the metal woven mesh 200 are interwoven with each other in an up-and-down manner, and the metal woven mesh 200 in a hollow tube shape is used to reflect and transmit a megahertz electromagnetic wave.

In detail, as shown in FIG3 and FIG4, the multiple warps 210 and multiple latitudes 220 of the metal woven mesh 200 of the deformable MHz optical reflector 100 of the present invention each have an equilateral hole width A, a metal wire diameter D and a metal bending angle θ. The equilateral hole width A is defined as the distance between two adjacent warps 210 or two adjacent latitudes 220, the metal wire diameter D is defined as a straight line of each warp 210 or each latitude 220, and the metal wire bending angle θ is defined as the bending angle of each warp 210 and each latitude 220 when they overlap each other to form an equilateral hole width.

In order to make the megahertz electromagnetic wave have a reflection efficiency almost close to total reflection when it is transmitted in the hollow tubular metal woven mesh 200, in a preferred embodiment, the equilateral hole width A of the metal woven mesh 200 of the deformable megahertz optical reflector 100 is between 0.070 and 0.280 millimeters (mm), the metal wire diameter D is between 0.030 and 0.130 mm, and the metal wire bending angle θ is between 36 and 50 degrees.

In more detail, the configuration relationship between parameters such as equilateral hole width A, metal wire diameter D and metal wire bending angle θ can be shown in Table 1:

It should be noted that the above-mentioned configuration relationship between the parameters such as the equilateral hole width A, the metal wire diameter D and the metal wire bending angle θ of the metal braided mesh 200 is mainly operated at the megahertz electromagnetic wave with a frequency between 0.1 and 1.5 megahertz (THz). Therefore, the metal material used in the metal braided mesh 200 of the present invention is not limited to its metal type. As long as the thickness of the pure metal surface layer of each meridian 210 and each latitude 220 of the metal braided mesh 200 is greater than 200 nanometers (nm) (i.e., the skin depth), it will have almost the same metal reflection or non-penetration performance for megahertz waves or electromagnetic waves of lower frequencies.

Please continue to refer to Figures 5 and 6. In one embodiment of the present invention, the hollow tube-shaped metal braided mesh 200 has a hollow tube length L and a hollow tube inner diameter R, and the hollow tube length L is 25 cm and the hollow tube inner diameter R is 8 mm, but this is not a limiting condition of the present invention.

As shown in FIG. 5 , the deformable MHz optical reflector 100 of the present invention may include a sleeve 300. The sleeve 300 is sleeved on the outer side of the metal woven mesh 200 to cover and fix the metal woven mesh 200 in a hollow tube shape. In other words, the sleeve 300 can help fix the bent and deformed metal woven mesh 200. In one embodiment, the sleeve 300 can be a heat shrink sleeve of PE plastic, but this is not a limiting condition of the present invention.

As shown in FIG. 7 , in another embodiment of the present invention, the hollow tubular metal braided mesh 200 can be made to present a contracted state. That is to say, the deformable megahertz optical reflector 100 of the present invention can be bent and deformed into a hollow triangular pyramid cavity according to different usage requirements, so that the deformable megahertz optical reflector 100 of the present invention forms a megahertz electromagnetic wave cavity that gathers or presents radiation pointing.

In one embodiment, the deformable MHz optical reflector 100 of the present invention may have an adsorbent on the surface of each meridian 210 and each latitude 220 of the metal woven mesh 200. The adsorbent can be used to adsorb specific molecules, thereby having the effect of sensing specific molecules. For example, the deformable megahertz optical reflector 100 of the present invention can be used to sense an organic volatile substance, so an organic volatile substance adsorbent can be made on the surface of each longitude 210 and each latitude 220 of the metal woven mesh 200. When the deformable megahertz optical reflector 100 is used in conjunction with the sleeve 300, when the holes of the metal woven mesh in a specific area without a sleeve receive and adsorb the organic volatile substance, the power change of the specific frequency megahertz wave transmitted from the inside of the hollow tube and the position of the deformable megahertz optical reflector 100 that adsorbs the organic volatile substance can remotely detect the organic volatile substance in a specific area.

In summary, since the deformable megahertz optical reflector 100 of the present invention can reflect megahertz electromagnetic waves of a specific frequency through the bending of the metal woven mesh 200, it can achieve the effect of deformability and high reflectivity under the condition of high porosity and no substrate support, thereby overcoming the existing technology of excessive thickness and poor reflectivity. In addition, the hollow tube formed by bending the high-porosity metal woven mesh 200 has an internal space that can circulate with the surrounding air environment, so the deformable megahertz optical reflector 100 of the present invention can also be used for gas sensing applications.

The above-mentioned embodiments are only for illustrating the technical ideas and features of the present invention. Their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly. They cannot be used to limit the patent scope of the present invention. In other words, any equivalent changes or modifications made according to the spirit disclosed by the present invention should still be covered by the patent scope of the present invention.

200: Metal woven mesh

210: Warp

220: Latitude

Claims (8)

A deformable megahertz optical reflector includes: a metal woven mesh having a plurality of longitudes and a plurality of latitudes, and the metal woven mesh is bent into a hollow tube; wherein the plurality of longitudes and the plurality of latitudes of the metal woven mesh are interwoven in an up-and-down manner, and the metal woven mesh in the hollow tube shape can transmit megahertz electromagnetic waves inside the hollow tube by optical mirror reflection. The deformable megahertz optical reflector as described in claim 1, wherein the plurality of warps and the plurality of latitudes of the metal woven mesh each have an equilateral hole width, a metal wire diameter and a metal bending angle, the equilateral hole width is the distance between two adjacent warps or two adjacent latitudes, the metal wire diameter is a straight line of each warp or each latitude, and the metal wire bending angle is the bending angle when each warp and each latitude overlap each other. The deformable MHz optical reflector as described in claim 2, wherein the width of the equilateral hole is between 0.070 and 0.280 mm, the diameter of the metal wire is between 0.030 and 0.130 mm, and the bending angle of the metal wire is between 36 and 50 degrees. A deformable megahertz optical reflector as described in claim 2, wherein the thickness of the pure metal surface layer of each of the warp and latitude of the metal woven mesh is greater than 200 nanometers (nm). A deformable megahertz optical mirror as described in claim 1, wherein the frequency of the megahertz electromagnetic wave is between 0.1 and 1.5 terahertz (THz). The deformable megahertz optical reflector as described in claim 5, wherein the metal braided mesh in the shape of a hollow tube has a hollow tube length and a hollow tube inner diameter, the hollow tube length is 25 cm, and the hollow tube inner diameter is 8 mm. The deformable MHz optical reflector as described in claim 1 further comprises a sleeve which is sleeved on the outer side of the metal braided mesh to cover and fix the metal braided mesh in the hollow tube shape. The deformable megahertz optical reflector as described in claim 1, wherein the surface of each of the warp and latitude of the metal woven mesh may have an adsorbent, and the adsorbent is used to adsorb specific molecules.