Optical construction and multilayer optical window

Abstract

An optical construction includes a plurality of alternating electrically conductive first and electrically insulative second layers stacked along a thickness direction of the optical construction. At least two of the layers in the first and the second layers define an air gap therebetween. Each of the electrically conductive first layers includes an electrically conductive two-dimensional mesh. For a first incident signal incident on the optical construction in a first incident plane, for each of s- and p-polarization states, for at least one frequency in a frequency range extending from about 0.5 gigahertz (GHz) to about 10 GHz, and for each of a first incident angle of less than about 10 degrees and a second incident angle of greater than about 20 degrees and less than about 60 degrees, the two-dimensional meshes, in combination, increase a transmission coefficient S21 of the optical construction by at least 1 decibel (dB).

Description

[0001] OPTICAL CONSTRUCTION AND MULTILAYER OPTICAL WINDOW

[0002] Technical Field

[0003] The present disclosure relates to an optical construction and a multilayer optical window.

[0004] Background

[0005] Typically, Insulating Glass Units (IGUs) are used for ensuring safety and optical transparency in structures, such as, buildings, vehicles, and the like. The IGUs are generally optimized for appropriate heat- and sound-insulation characteristics within the structures using a multilayer structure. However, such a multilayer structure of the IGUs may result in a poor radio frequency (RF) transmission.

[0006] Summary

[0007] In a first aspect, the present disclosure provides an optical construction. The optical construction includes a plurality of alternating electrically conductive first and electrically insulative second layers stacked along a thickness direction of the optical construction. At least two of the layers in the first and the second layers define an air gap therebetween. Each of the electrically conductive first layers includes an electrically conductive two-dimensional mesh. The mesh includes a plurality of electrically conductive traces connected to define a plurality of enclosed open areas. The mesh has a percent open area of greater than about 20% and an effective sheet resistance of less than about 10 ohms per square. For a first incident signal incident on the optical construction in a first incident plane, for each of s- and p-polarization states, for at least one frequency in a frequency range extending from about 0.5 gigahertz (GHz) to about 10 GHz, and for each of a first incident angle of less than about 10 degrees and a second incident angle of greater than about 20 degrees and less than about 60 degrees, the two-dimensional meshes of the electrically conductive first layers, in combination, increase a transmission coefficient S21 of the optical construction by at least 1 decibel (dB).

[0008] In a second aspect, the present disclosure provides an optical construction. The optical construction includes substantially parallel two-dimensional electrically conductive first and second meshes defining an air gap therebetween. Each of the first and second meshes includes a plurality of electrically conductive traces connected to form a plurality of regularly arranged cells. The first and second meshes have different cell pitches along a same in-plane first direction. The optical construction further includes at least one electrically insulative substrate disposed between the first and second meshes. The at least one substrate, the air gap, and the first and second meshes are substantially co-extensive with one another in width and length. An average thickness of the air gap is greater than an average thickness of at least one of the substrates in the at least one substrate. For a first incident signal incident on the optical construction in a first incident plane, for each of s- and p-polarization states, for at least one frequency in a frequency range extending from about 0.5 GHz to about 10 GHz, and for at least two of a first incident angle of less than about 10 degrees, a second incident angle of greater than the first incident angle by at least 20 degrees, and a third incident angle of greater than the second incident angle by at least 5 degrees, the first and second meshes of the optical construction, in combination, increase a transmission coefficient S21 of the optical construction by at least 1 dB.

[0009] In a third aspect, the present disclosure provides an optical constmction. The optical construction includes substantially parallel two-dimensional first, second, and third metallic meshes defining one or more air gaps therebetween. Each of the three meshes includes a plurality of metal traces connected to form a plurality of enclosed open areas and a percent open area of greater than about 20%. The optical construction further includes at least one electrically insulative substrate disposed between two of the three metallic meshes. The at least one substrate, the one or more air gaps, and the three metallic meshes are substantially co-extensive with one another in width and length. For a substantially normally incident signal, for at least one of s- and p-polarization states, and for continuous first and second frequency ranges that are spaced apart from each other by at least 0.2 GHz and are each disposed between about 0.5 GHz to about 10 GHz and is at least 0.05 GHz wide, the optical construction has a transmission coefficient S21 of greater than about -1.6 dB.

[0010] In a fourth aspect, the present disclosure provides a multilayer optical window. The multilayer optical window includes two glass substrates stacked along a thickness direction of the window and define an air gap therebetween. The multilayer optical window further includes first, second, and third metallic meshes spaced apart from each other and disposed on the two glass substrates. The three meshes, the two glass substrates, and the air gap are substantially co-extensive with each other along a width and a length of the window. Each of the three metallic meshes includes a plurality of metal traces intersecting to form a plurality of cells arranged regularly across the width and the length of the window. At least two of the three meshes have different cell pitches along a same in-plane first direction. For a first incident signal incident on the window in a first incident plane, for at least one of s- and p-polarization states, for each frequency in a continuous first frequency range that is at least 0.25 GHz wide and is disposed within a frequency range extending from about 0.5 GHz to about 10 GHz, and for each of a first incident angle of less than about 10 degrees, a second incident angle of greater than the first incident angle by at least 20 degrees, and a third incident angle of greater than the second incident angle by at least 5 degrees, the three meshes of the window, in combination, increase a transmission coefficient S21 of the window by at least 1 dB while reducing the optical transmission of the window by less than about 20% for at least one visible wavelength between about 420 nm and about 680 nm.

[0011] In a fifth aspect, the present disclosure provides a building. The building includes a building window including the multilayer optical window of the fourth aspect.

[0012] In a sixth aspect, the present disclosure provides a vehicle. The vehicle includes a vehicle window including the multilayer optical window of the fourth aspect.

[0013] The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims. Brief Description of the Drawings

[0014] Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0015] FIG. 1 shows a schematic sectional view of an optical construction, according to an embodiment of the present disclosure;

[0016] FIG. 2A shows a schematic top view of an electrically conductive first layer having a two- dimensional conductive mesh, according to an embodiment of the present disclosure;

[0017] FIG. 2B shows a schematic top view of the electrically conductive first layer illustrating a cell pitch of the two-dimensional conductive mesh, according to an embodiment of the present disclosure;

[0018] FIG. 2C shows a schematic top view of the electrically conductive first layer illustrating the cell pitch of the two-dimensional conductive mesh, according to another embodiment of the present disclosure;

[0019] FIG. 3 A shows a schematic sectional view of a conductive trace of the conductive mesh, according to an embodiment of the present disclosure;

[0020] FIG. 3B shows a schematic sectional view of the conductive trace of the conductive mesh, according to another embodiment of the present disclosure;

[0021] FIGS. 4A shows a schematic sectional view of the optical construction and first incident signals incident thereon in a first incident plane, according to an embodiment of the present disclosure;

[0022] FIG. 4B shows a schematic side view of the optical construction and one of the first incident signals incident thereon, according to an embodiment of the present disclosure;

[0023] FIG. 5 A shows a graph depicting transmission coefficients S21 of the optical construction and a comparative optical construction versus frequency for a p- polarization state, according to an embodiment of the present disclosure;

[0024] FIG. 5B shows a graph depicting transmission coefficients S21 of the optical construction and the comparative optical constmction versus frequency for an s- polarization state, according to an embodiment of the present disclosure;

[0025] FIG. 6 A shows a graph depicting transmission coefficients S21 of the optical construction and the comparative optical construction versus frequency for the p-polarization state, according to another embodiment of the present disclosure;

[0026] FIG. 6B shows a graph depicting transmission coefficients S21 of the optical construction and the comparative optical construction versus frequency for the s-polarization state, according to another embodiment of the present disclosure;

[0027] FIG. 7 A shows a graph depicting transmission coefficients S21 of the optical construction and the comparative optical construction versus frequency for the p-polarization state, according to yet another embodiment of the present disclosure; FIG. 7B shows a graph depicting transmission coefficients S21 of the optical construction and the comparative optical construction versus frequency for the s-polarization state, according to yet another embodiment of the present disclosure;

[0028] FIG. 7C shows a graph depicting the transmission coefficients S21 of the optical construction and the comparative optical construction versus frequency for the first incident signal incident at a first incident angle, according to an embodiment of the present disclosure;

[0029] FIG. 8 A shows a graph depicting transmission coefficients S21 of an optical window and a comparative optical window versus frequency for the p-polarization state, according to an embodiment of the present disclosure;

[0030] FIG. 8B shows a graph depicting transmission coefficients S21 of the optical window and the comparative optical window versus frequency for the s-polarization state, according to an embodiment of the present disclosure;

[0031] FIG. 8C shows a graph depicting the transmission coefficients S21 of the optical window and the comparative optical window versus frequency for the first incident signal incident at the first incident angle, according to an embodiment of the present disclosure;

[0032] FIG. 9A shows a schematic view of a building, according to an embodiment of the present disclosure; and

[0033] FIG. 9B shows a schematic view of a vehicle, according to an embodiment of the present disclosure.

[0034] Detailed Description

[0035] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0036] In the following disclosure, the following definitions are adopted.

[0037] As used herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0038] As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within + / - 20 % for quantifiable properties).

[0039] The term “substantially”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 10% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0040] The term “about”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 5% for quantifiable properties) but again without requiring absolute precision or a perfect match. As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

[0041] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

[0042] As used herein, the term “transmission coefficient” refers to a measure of how much of an electromagnetic wave (e.g., light) passes through a surface or an optical element. Further, as used herein, the term “transmission coefficient S21” indicates an insertion loss or gain.

[0043] Typically, Insulating Glass Units (IGUs) are used for ensuring safety and optical transparency in structures, such as, buildings, vehicles, and the like. The IGUs are generally optimized for appropriate heat- and sound-insulation characteristics within the structures using a multilayer structure. However, such a multilayer structure of the IGUs may result in a poor radio frequency (RF) transmission (e.g., the multilayer structure having several internal interfaces may result in an onset of interference conditions). This poor RF transmission may be due to high Return Losses (e.g., Fresnel losses, and / or impedance mismatch, specially from outermost surfaces), with Dielectric Losses playing only a secondary role. This may negatively affect typical cellular and wireless communication within the structures.

[0044] The present disclosure relates to an optical construction and a multilayer optical window. The optical construction includes a plurality of alternating electrically conductive first and electrically insulative second layers stacked along a thickness direction of the optical construction. At least two of the layers in the first and the second layers define an air gap therebetween. Each of the electrically conductive first layers includes an electrically conductive two-dimensional mesh. The mesh includes a plurality of electrically conductive traces connected to define a plurality of enclosed open areas. The mesh has a percent open area of greater than about 20% and an effective sheet resistance of less than about 10 ohms per square. For a first incident signal incident on the optical construction in a first incident plane, for each of s- and p- polarization states, for at least one frequency in a frequency range extending from about 0.5 gigahertz (GHz) to about 10 GHz, and for each of a first incident angle of less than about 10 degrees and a second incident angle of greater than about 20 degrees and less than about 60 degrees, the two-dimensional meshes of the electrically conductive first layers, in combination, increase a transmission coefficient S21 of the optical construction by at least 1 decibel (dB).

[0045] Therefore, the optical construction may improve RF wave transmission of the electrically insulative second layers (i.e., electrically thick dielectric materials and composites) for a wide range of angles (e.g., the first and second incident angles) and operating frequencies (e.g., the frequency range) using the electrically conductive two-dimensional mesh in each of the electrically conductive first layers.

[0046] Referring now to figures, FIG. 1 is a schematic sectional view of an optical construction 300, according to an embodiment of the present disclosure. In some embodiments, the optical construction 300 may be a multilayer optical window and may be interchangeably referred to as “the multilayer optical window 300”, “the optical window 300”, or “the window 300”. The optical construction 300 defines mutually orthogonal x, y, and z-axes. The x and y-axes are in-plane axes of the optical construction 300, while the z-axis is a transverse axis disposed along a thickness of the optical construction 300. In other words, the x and y-axes are disposed along a plane of the optical construction 300, while the z-axis is perpendicular to the plane of the optical construction 300.

[0047] The optical construction 300 includes a plurality of alternating electrically conductive first and electrically insulative second layers 40, 30. The plurality alternating electrically conductive first and electrically insulative second layers 40, 30 are stacked along a thickness direction of the optical construction 300. In some embodiments, the thickness direction of the optical construction 300 may be substantially along the z-axis.

[0048] In the illustrated embodiment of FIG. 1, the plurality of electrically conductive first layers 40 includes electrically conductive first layers 40a, 40b, 40c. Each of the electrically conductive first layers 40 includes an electrically conductive two-dimensional mesh. Accordingly, the electrically conductive first layers 40 may be interchangeably referred to as “the two-dimensional meshes 40” or “the meshes 40”.

[0049] Each of the electrically conductive two-dimensional meshes 40 extends along width and length of the optical construction 300. In some embodiments, the width of the optical construction 300 may be substantially along the y-axis, and the length of the optical construction 300 may be substantially along the x-axis.

[0050] In some embodiments, the plurality of alternating electrically conductive first and electrically insulative second layers 40, 30 includes only two electrically conductive first layers 40. In some embodiments, the optical construction 300 includes only two electrically conductive two-dimensional meshes 40. In some embodiments, the optical construction 300 includes at least three electrically conductive two-dimensional meshes 40. In the illustrated embodiment of FIG. 1, the optical construction 300 includes three electrically conductive two-dimensional meshes 40 (i.e., the meshes 40a, 40b, 40c).

[0051] In some embodiments, any two neighboring meshes 40 in the plurality of meshes 40 are spaced apart by at least 1 millimeter (mm). In some embodiments, any two neighboring meshes 40 in the plurality of meshes 40 are spaced apart by at least 2 mm, at least 3 mm, at least 4 mm, at least 5 mm, at least 8 mm, at least 10 mm, at least 15 mm, at least 20 mm, at least 25 mm, at least 30 mm, at least 35 mm, at least 40 mm, at least 45 mm, or at least 50 mm. In some embodiments, the two neighboring meshes 40 in the plurality of meshes 40a, 40b, 40c are spaced apart by about 8 mm.

[0052] In the illustrated embodiment of FIG. 1, the plurality of electrically insulative second layers 30 includes electrically insulative second layers 30a, 30b, 30c. Each of the plurality of electrically insulative second layers 30a, 30b, 30c has an average thickness. In the illustrated embodiment of FIG. 1, the electrically insulative second layers 30a, 30b, 30c have corresponding average thicknesses ha, hb, he. Specifically, the electrically insulative second layer 30a has the average thickness ha, the electrically insulative second layer 30b has the average thickness hb, and the electrically insulative second layer 30c has the average thickness he. In some embodiments, each of the average thicknesses ha, hb, and he of the plurality of electrically insulative second layers 30a, 30b, 30c is about 4 mm. In some embodiments, each of the electrically insulative second layers 30 is an electrically insulative substrate. In some cases, each of the electrically insulative second layers 30 may be made of a dielectric material. In an embodiment, each of the electrically insulative second layers 30 is a glass substrate. Accordingly, the electrically insulative second layers 30 may be interchangeably referred to as “the substrate 30” or “the glass substrate 30”.

[0053] In some embodiments, the multilayer optical window 300 includes two glass substrates 30 (i.e. , the glass substrates 30b, 30c) stacked along the thickness direction of the window 300.

[0054] In some embodiments, the optical construction 300 includes substantially parallel two-dimensional electrically conductive first and second meshes (for example, the two-dimensional electrically conductive meshes 40a, 40c) and at least one electrically insulative substrate (for example, at least one of the electrically insulative substrates 30a, 30b, 30c) disposed between the first and second meshes, i.e., the electrically conductive meshes 40a, 40c.

[0055] In some embodiments, the optical constmction 300 includes substantially parallel two-dimensional first, second, and third metallic meshes (for example, the two-dimensional electrically conductive meshes 40a, 40b, 40c) and at least one electrically insulative substrate (for example, at least one of the electrically insulative substrates 30a, 30b, 30c) disposed between two of the three metallic meshes, i.e., the electrically conductive meshes 40a, 40b, 40c.

[0056] In an embodiment, one of the plurality of electrically conductive first layers 40 and one of the plurality of electrically insulative second layers 30 may be attached together and may be referred to as a paired film 10. In the illustrated embodiment of FIG. 1, the optical construction 300 includes the paired films 10a, 10b, 10c having the electrically conductive first layers 40a, 40b, 40c, and the corresponding electrically insulative second layers 30a, 30b, 30c. In some embodiments, each of the paired films 10a, 10b, 10c may be integrally formed. In some embodiments, each of the meshes 40a, 40b, 40c may be deposited on the corresponding electrically insulative second layer 30a, 30b, 30c. For example, the mesh 40a may be deposited on the electrically insulative second layer 30a to form the paired film 10a, the mesh 40b may be deposited on the electrically insulative second layer 30b to form the paired film 10b, and the mesh 40c may be deposited on the electrically insulative second layer 30c to form the paired film 10c.

[0057] In some embodiments, two adjacent paired films 10 (e.g., the paired films 10a, 10b) are bonded together using a bonding layer 70. In some embodiments, two adjacent electrically insulative second layers (e.g., the electrically insulative second layers 30a, 30b) of the paired films 10a, 10b may be bonded together using the bonding layer 70. In some embodiments, the bonding layer 70 may include an optically clear adhesive (OCA).

[0058] At least two of the layers in the first and the second layers 40, 30 define an air gap 20 therebetween. For example, in the illustrated embodiment of FIG. 1, the first and the second layers 40b, 30c define the air gap 20 therebetween.

[0059] In some embodiments, the substantially parallel two-dimensional electrically conductive first and second meshes (e.g., the meshes 40a, 40c) define the air gap 20 therebetween. In some embodiments, the substantially parallel two-dimensional first, second, and third metallic meshes (e.g., the meshes 40a, 40b, 40c) define one or more air gaps (e.g., the air gap 20) therebetween. In some embodiments, the two glass substrates 30 (i.e., the glass substrates 30b, 30c) define the air gap 20 therebetween.

[0060] In some embodiments, the air gap 20 and the at least two of the layers (e.g., the first and the second layers 40b, 30c) in the first and the second layers 40, 30 defining the air gap 20 are substantially coextensive with each other in the length (i.e., substantially along the x-axis) and the width (i.e., substantially along the y-axis).

[0061] In some embodiments, the at least one substrate 30a, 30b, 30c, the air gap 20, and the first and second meshes (i.e., the meshes 40a, 40c) are substantially co-extensive with one another in the width and the length.

[0062] In some embodiments, the at least one substrate 30a, 30b, 30c, the one or more air gaps 20, and the three metallic meshes (i.e., the meshes 40a, 40b, 40c) are substantially co-extensive with one another in the width and the length.

[0063] In some embodiments, the first, second, and third metallic meshes (i.e., the meshes 40a, 40b, 40c) are spaced apart from each other and are disposed on the two glass substrates 30. The three meshes 40, the two glass substrates 30, and the air gap 20 are substantially co-extensive with each other along the width and the length of the window 300.

[0064] In some embodiments, the air gap 20 has an average thickness hl of greater than about 5 mm. In some embodiments, the air gap 20 has the average thickness hl of greater than about 7 mm, greater than about 9 mm, greater than about 10 mm, greater than about 12 mm, greater than about 15 mm, greater than about 19 mm, greater than about 20 mm, greater than about 25 mm, or greater than about 30 mm. In the illustrated embodiment of FIG. 1, the air gap 20 has the average thickness hl of about 19.24 mm.

[0065] In some embodiments, the average thickness hl of the air gap 20 is greater than the average thickness ha, hb, he of at least one of the substrates 30a, 30b, 30c in the at least one substrate 30. In some embodiments, the average thickness hl of the air gap 20 is greater than the average thickness ha, hb, he of the at least one of the substrates 30a, 30b, 30c in the at least one substrate 30a, 30b, 30c by at least 1 mm. In some embodiments, the average thickness hl of the air gap 20 is greater than the average thickness ha, hb, he of the at least one of the substrates 30a, 30b, 30c in the at least one substrate 30a, 30b, 30c by at least 2 mm, at least 3 mm, at least 4 mm, at least 5 mm, at least 10 mm, at least 12 mm, or at least 15mm. In some embodiments, the average thickness hl of the air gap 20 is greater than the average thickness ha, hb, he of the at least one of the substrates 30a, 30b, 30c in the at least one substrate 30a, 30b, 30c by about 15.24 mm.

[0066] In some embodiments, for a substantially normally incident light, for each of mutually orthogonal first and second polarization states, and for at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm, the optical construction 300 has a total optical transmittance of at least about 20%. In some embodiments, for the substantially normally incident light, for each of the first and second polarization states, and for the at least one visible wavelength in the visible wavelength range, the optical construction 300 has the total optical transmittance of at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, or at least about 95%. In some embodiments, the at least one visible wavelength may include a blue wavelength, a green wavelength, or a red wavelength. In some embodiments, the first polarization state may extend substantially along the x-axis and the second polarization state may substantially extend along the y-axis.

[0067] Therefore, the optical construction 300 may have a desired optical transmittance for the substantially normally incident light, for each of the first and second polarization states, and for the at least one visible wavelength in the visible wavelength. In other words, the meshes 40 may not negatively affect the optical transmittance of the optical construction 300.

[0068] FIG. 2A is a schematic top view of the electrically conductive first layer having the two- dimensional conductive mesh 40, according to an embodiment of the present disclosure. FIG. 2B is a schematic top view of the electrically conductive first layer having a two-dimensional conductive mesh 40’, according to an embodiment of the present disclosure. FIG. 2C is a schematic top view of the electrically conductive first layer having a two-dimensional conductive mesh 40a’, according to another embodiment of the present disclosure.

[0069] Referring to FIGS. 2A-2C, the mesh 40 includes a plurality of electrically conductive traces 41 connected to define a plurality of enclosed open areas 42. In some embodiments, each of the first and second meshes (for example, the meshes 40a, 40c shown in FIG. 1) includes the plurality of electrically conductive traces 41 connected to form a plurality of regularly arranged cells. In some embodiments, each of the three meshes (for example, the meshes 40a, 40b, 40c shown in FIG. 1) includes the plurality of metal traces 41 that are connected to form the plurality of enclosed open areas 42. In some embodiments, each of the three metallic meshes 40 includes the plurality of metal traces 41 that intersect to form a plurality of cells arranged regularly across the width and the length of the window 300.

[0070] Therefore, the plurality of enclosed open areas 42 may be interchangeably referred to as “the plurality of regularly arranged cells 42” or “the plurality of cells 42”.

[0071] The mesh 40 has a percent open area of greater than about 20%. In some embodiments, the mesh 40 has the percent open area of greater than about 30%, greater than about 40%, greater than about 50%, greater than about 60%, greater than about 70%, greater than about 80%, greater than about 90%, or greater than about 95%.

[0072] Further, the mesh 40 has an effective sheet resistance of less than about 10 ohms per square. In some embodiments, the mesh 40 has the effective sheet resistance of less than about 5 ohms per square, less than about 1 ohm per square, less than about 0.05 ohms per square, less than about 0.01 ohms per square, less than about 0.005 ohms per square, or less than about 0.001 ohms per square. In some embodiments, the mesh 40 has the effective sheet resistance of about 0.0032 ohms per square.

[0073] As shown in FIGS. 2B and 2C, in some embodiments, the plurality of meshes 40, 40’, 40a’ may have different pitches along a same in-plane first direction. In some embodiments, the first direction may be substantially along the x-axis.

[0074] In some embodiments, the traces 41 of the at least one mesh 40 in the plurality of meshes 40 connect to form a plurality of one or more of square cells and rectangular cells. For instance, as shown in FIG. 2B, the traces 41 of the mesh 40’ of the plurality of meshes 40 connect to form the plurality of square cells having a cell pitch Ml, and as shown in FIG. 2C, the traces 41 of the mesh 40a’ of the plurality of meshes 40 connect to form the plurality of rectangular cells having the cell pitch M2.

[0075] Referring to FIGS. 1 and 2A-2C, in some embodiments, the first and second meshes (e.g., the meshes 40a, 40c) have the different cell pitches Ml, M2 along the same in-plane first direction (i.e., substantially along the x-axis). In some embodiments, at least two of the three meshes 40 (e.g., the meshes 40a, 40b, 40c) have the different cell pitches Ml, M2 along the same in-plane first direction. In some embodiments, each of the at least two of the three meshes 40 includes the plurality of regularly arranged metal cells 42.

[0076] FIG. 3 A is a schematic sectional view of a conductive trace 41 from the plurality of conductive traces 41 of the mesh 40 shown in FIG. 2A, according to an embodiment of the present disclosure. FIG. 3B illustrates a schematic sectional view of a conductive trace 41 from the plurality of conductive traces 41 of the mesh 40 shown in FIG. 2A, according to another embodiment of the present disclosure.

[0077] In some embodiments, as shown in FIG. 3 A, each of the conductive traces 41 of the mesh 40 is a single electrically conductive layer 41a. In some embodiments, as shown in FIG. 3B, each of the conductive traces 41 of the mesh 40 includes multiple electrically conductive layers 41b, 41c, 4 Id stacked along the thickness direction of the optical constmction 300 shown in FIG. 1.

[0078] In some embodiments, the conductive traces 41 of the mesh 40 includes one or more metals. In some embodiments, the one or more metals include one or more of silver, titanium, copper, gold, and aluminum.

[0079] In some embodiments, the conductive traces 41 of the mesh 40 have an average thickness of less than about 20 microns. In some embodiments, the conductive traces 41 of the mesh 40 have the average thickness of less than about 15 microns or less than about 10 microns. In some embodiments, the conductive traces 41 of the mesh 40 have the average thickness of about 5 microns.

[0080] In some embodiments, the conductive traces 41 of the mesh 40 have an average width of less than about 50 microns. In some embodiments, the conductive traces 41 of the mesh 40 have the average width of less than about 45 microns, less than about 40 microns, or less than about 35 microns. In some embodiments, the conductive traces 41 of the mesh 40 have the average width of about 30 microns.

[0081] FIG. 4A illustrates a schematic sectional view of the optical construction 300 and first incident signals 50a, 50b, 50c incident thereon in a first incident plane P 1 , according to an embodiment of the present disclosure. Specifically, FIG. 4A illustrates the first incident signal 50a incident on the optical construction 300 at a first incident angle al in the first incident plane Pl, the first incident signal 50b incident on the optical construction 300 at a second incident angle a2 in the first incident plane Pl, and the first incident signal 50c incident on the optical construction 300 at a third incident angle a3 in the first incident plane Pl.

[0082] The first incident angle al is less than about 10 degrees. In some embodiments, the first incident angle al is less than about 8 degrees, less than about 6 degrees, less than about 4 degrees, less than about 2 degrees, or less than about 1 degree. In some embodiments, the first incident angle al is about 0 degree. Therefore, the first incident signal 50a may be interchangeably referred to as “the substantially normally incident signal 50a”.

[0083] The second incident angle a2 is greater than the first incident angle al by at least 20 degrees. In some embodiments, the second incident angle a2 is greater than the first incident angle al by at least 25 degrees, at least 30 degrees, at least 35 degrees, at least 40 degrees, or at least 45 degrees. In some embodiments, the second incident angle a2 is greater than the first incident angle al by about 40 degrees.

[0084] In some embodiments, the second incident angle a2 is greater than about 20 degrees and less than about 60 degrees. In some embodiments, the second incident angle a2 is greater than about 25 degrees, greater than about 30 degrees, greater than about 35 degrees, or greater than about 40 degrees, and less than about 55 degrees, less than about 50 degrees, less than about 45 degrees, or less than about 40 degrees. In some embodiments, the second incident angle a2 is about 40 degrees.

[0085] The third incident angle a3 is greater than the second incident angle a2 by at least 5 degrees. In some embodiments, the third incident angle a3 is greater than the second incident angle a2 by at least 10 degrees, at least 15 degrees, at least 20 degrees, or at least 25 degrees. In some embodiments, the third incident angle a3 is greater than the second incident angle a2 by about 20 degrees. In some embodiments, the third incident angle a3 is about 60 degrees.

[0086] Each of the first incident signals 50a, 50, 50c has s- and p-polarization states 51, 52 (shown for the first incident signal 50c). Specifically, each of the first incident signals 50a, 50, 50c has the s-polarization state 51 and the p-polarizations state 52.

[0087] In some embodiments, the first incident signals 50a, 50b, 50c may be electromagnetic signals and each of the first incident signals 50a, 50b, 50c may include a transverse electric component TE and a transverse magnetic component TM. The transverse electric component TE and the transverse magnetic component TM are substantially orthogonal to each other.

[0088] In some embodiments, the s-polarization state 51 may allow transmission of the transverse magnetic component TM, and the p-polarization state 52 may allow transmission of the transverse electric component TE.

[0089] FIG. 4B is a schematic side view of the optical construction 300 and the first incident signal 50c incident thereon at the third incident angle a3, according to an embodiment of the present disclosure. As shown, the first incident signal 50c is incident on the optical construction 300 at the third incident angle a3 in the first incident plane Pl. FIG. 4B further shows the s-polarization state 51 and the p-polarization state 52 of the first incident signal 50c.

[0090] FIG. 5 A shows a graph 500 depicting transmission coefficients S21 of the optical construction 300 (shown in FIG. 1) and a comparative optical construction versus frequency for the p- polarization state 52 (shown in FIG. 4A), according to an embodiment of the present disclosure.

[0091] FIG. 5B shows a graph 550 depicting transmission coefficients S21 of the optical construction 300 and the comparative optical construction versus frequency for the s- polarization state 51 (shown in FIG. 4A), according to an embodiment of the present disclosure. It is to be noted that the comparative optical construction is substantially similar to the optical construction 300 shown in FIG. 1 and includes the plurality of substrates 30, however, the comparative optical construction does not include the plurality of electrically conductive meshes 40 (shown in FIG. 1).

[0092] In some embodiments, the optical construction 300 may include the plurality of substrates 30 (shown in FIG. 1) stacked together and the mesh 40 arranged at each outer surface of the plurality of substrates 30. In some embodiments, the meshes 40 may have same cell pitches (e.g., the cell pitch Ml shown in FIG. 2B or the cell pitch M2 shown in FIG. 2C). In some embodiments, the cell pitch of each of the meshes 40 may be about 11 mm.

[0093] FIG. 5 A shows the graph 500 depicting the transmission coefficients S21 of the optical constmction 300 for the first incident signals 50a, 50b (shown in FIG. 4A) having the p-polarization state 52. The graph 500 further depicts the transmission coefficient S21 of the comparative optical construction for the first incident signals 50a, 50b having the p-polarization state 52.

[0094] FIG. 5B shows the graph 550 depicting the transmission coefficients S21 of the optical construction 300 for the first incident signals 50a, 50b having the s-polarization state 51 , and the transmission coefficient S21 of the comparative optical construction for the first incident signals 50a, 50b having the s-polarization state 51.

[0095] Frequency is expressed in gigahertz (GHz) in the abscissa. The transmission coefficient S21 is expressed in decibels (dB) in the ordinate.

[0096] The graph 500 includes a plot 502 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the optical construction 300.

[0097] The graph 500 further includes a plot 504 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the optical construction 300.

[0098] The graph 500 further includes a plot 512 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the comparative optical construction.

[0099] The graph 500 further includes a plot 514 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the comparative optical construction.

[0100] The graph 550 includes a plot 552 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the optical construction 300.

[0101] The graph 550 further includes a plot 554 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50b having the s-polarization state 51 and incident at the second incident angle a2 on the optical construction 300. The graph 550 further includes a plot 562 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the comparative optical construction.

[0102] The graph 550 further includes a plot 564 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50b having the s-polarization state 51 and incident at the second incident angle a2 on the comparative optical construction.

[0103] Referring to FIGS. 1, 4A, and 5A-5B, as is apparent from the graphs 500, 550, for the first incident signal 50a, 50b incident on the optical construction 300 in the first incident plane Pl, for each of the s- and p-polarization states 51, 52, for at least one frequency Fl in a frequency range extending from about 0.5 GHz to about 10 GHz, and for each of the first incident angle al and the second incident angle a2, the two- dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 of the optical construction 300 by at least 1 decibel (dB).

[0104] In some embodiments, for the first incident signal 50a, 50b incident on the optical construction 300 in the first incident plane Pl, for each of the s- and p-polarization states 51, 52, for the at least one frequency Fl, and for each of the first incident angle al and the second incident angle a2, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 of the optical construction 300 by at least 1.2 dB, at least 1.4 dB, at least 1.6 dB, or at least 1.8 dB.

[0105] In some embodiments, for the first incident signal 50a, 50b, for the p-polarization state 52, for the at least one frequency Fl, and for each of the first and second incident angles al, a2, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 of the optical construction 300 by at least 2 dB. In some embodiments, forthe first incident signal 50a, 50b, for the p-polarization state, for the at least one frequency Fl, and for each of the first and the second incident angles al, a2, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 of the optical construction 300 by at least 2.5 dB, at least 3 dB, at least 3.5 dB, or at least 4 dB.

[0106] In some embodiments, for the first incident signal 50a, for the p-polarization state 52, for the first incident angle al of about 0 degree, and for the at least one frequency Fl of about 4 GHz, the two- dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 (indicated by si in FIG. 5A) of the optical construction 300 by about 4.2 dB, and for the first incident signal 50b, for the p-polarization state 52, for the second incident angle a2 of about 40 degrees, and for the at least one frequency Fl of about 4 GHz, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 (indicated by s2 in FIG. 5A) of the optical construction 300 by about 6.6 dB.

[0107] In some embodiments, for the first incident signal 50a, for the s-polarization state 51, for the first incident angle al of about 0 degree, for the at least one frequency Fl of about 4GHz, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 (indicated by s3 in FIG. 5B) of the optical construction 300 by about 4.2 dB, and for the first incident signal 50b, for the s-polarization state 51 , for the second incident angle a2 of about 40 degrees, for the at least one frequency Fl of about 4GHz, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 (indicated by s4 in FIG. 5B) of the optical construction 300 by about 1.8 dB.

[0108] Accordingly, in some embodiments, for the first incident signal 50a, 50b, for the at least one frequency Fl, and when the incident angle increases from the first incident angle al to the second incident angle a2, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 of the optical construction 300 for the p-polarization state 52 and decrease the transmission coefficient S21 of the optical construction 300 for the s-polarization state 51.

[0109] In some embodiments, the increase (i.e., in the transmission coefficient S21 in the p-polarization state 52) is at least 1 dB and the decrease (i.e., in the transmission coefficient S21 in the s-polarization state 51) is at least IdB. In some embodiments, the increase is at least 1.5 dB, or at least 2 dB, and the decrease is at least 1.5 dB, or at least 2 dB.

[0110] In some embodiments, for the first incident signal 50a, 50b, for the at least one frequency Fl, as the incident angle increases from the first incident angle al of about 0 degree to the second incident angle a2 of about 40 degrees, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, increase the transmission coefficient S21 of the optical constmction 300 for the p-polarization state 52 from about 4.2 dB to about 6.6 dB, and decrease the transmission coefficient S21 of the optical construction 300 forthe s-polarization state 51 from about 4.2 dB to about 1.8 dB. Accordingly, the increase in the transmission coefficient S21 in the p-polarization state 52 is about 2.4 dB and the decrease in the transmission coefficient S21 in the s-polarization state 51 is about 2.4 dB.

[0111] Further, as is apparent from the graphs 500, 550, for the first incident signal 50a, 50b, for each of the s- and p-polarization states 51, 52, for at least one second frequency Fl ’ in a frequency range extending from about 0.25 GHz to about 5 GHz, and for each of the first and second incident angles al, a2, the two- dimensional meshes 40 of the electrically conductive first layers 40, in combination, decrease the transmission coefficient S21 of the optical construction 300 by at least 2 dB. In some embodiments, for the first incident signal 50a, 50b, for each of the s- and p-polarization states 51, 52, for the at least one second frequency Fl’, and for each of the first and second incident angles al, a2, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, decrease the transmission coefficient S21 of the optical construction 300 by at least 4 dB, at least 6 dB, at least 8 dB, or at least 10 dB.

[0112] In some embodiments, for the first incident signal 50a, 50b, for the at least one second frequency Fl’ of about 1 GHz, and for each of the first and second incident angles al, a2, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, decrease the transmission coefficient S21 of the optical construction 300 by more than about 14 dB for the p-polarization state 52, and more than about 10 dB for the s-polarization state 51.

[0113] FIG. 6 A shows a graph 600 depicting transmission coefficients S21 of the optical construction 300 (shown in FIG. 1) and the comparative optical construction versus frequency for the p-polarization state 52, according to another embodiment of the present disclosure. FIG. 6B shows a graph 650 depicting transmission coefficients S21 of the optical construction 300 and the comparative optical construction versus frequency for the s-polarization state 51, according to another embodiment of the present disclosure.

[0114] In some embodiments, the optical construction 300 may include the plurality of substrates 30 (shown in FIG. 1) stacked together and the mesh 40 arranged at each outer surface of the plurality of substrates 30. In such embodiments, each of the meshes 40 may have different cell pitches (e.g., the cell pitch Ml and the cell pitch M2). In an exemplary embodiment, one of the meshes 40 may have the cell pitch of about 8 mm and another of the meshes 40 may have the cell pitch of about 16 mm.

[0115] FIG. 6 A shows the graph 600 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signals 50a, 50b, 50c (shown in FIG. 4A) having the p-polarization state 52 and incident on the optical construction 300, and the transmission coefficient S21 of the comparative optical construction for the first incident signals 50a, 50b, 50c having the p-polarization state 52 and incident on the comparative optical construction.

[0116] FIG. 6B shows the graph 650 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signals 50a, 50b, 50c having the s-polarization state 51 and incident on the optical construction 300, and the transmission coefficient S21 of the comparative optical construction for the first incident signals 50a, 50b, 50c having the s-polarization state 51 and incident on the comparative optical construction.

[0117] Frequency is expressed in gigahertz (GHz) in the abscissa. The transmission coefficient S21 is expressed in decibels (dB) in the ordinate.

[0118] The graph 600 includes a plot 602 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the optical construction 300.

[0119] The graph 600 further includes a plot 604 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the optical construction 300.

[0120] The graph 600 further includes a plot 606 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3 on the optical construction 300.

[0121] The graph 600 further includes a plot 612 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the comparative optical construction.

[0122] The graph 600 further includes a plot 614 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the comparative optical construction.

[0123] The graph 600 further includes a plot 616 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3 on the comparative optical construction. The graph 650 includes a plot 652 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the optical construction 300.

[0124] The graph 650 further includes a plot 654 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50b having the s-polarization state 51 and incident at the second incident angle a2 on the optical construction 300.

[0125] The graph 650 further includes a plot 656 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50c having the s-polarization state 51 and incident at the third incident angle a3 on the optical construction 300.

[0126] The graph 650 further includes a plot 662 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the comparative optical construction.

[0127] The graph 650 further includes a plot 664 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50b having the s-polarization state 51 and incident at the second incident angle a2 on the comparative optical construction.

[0128] The graph 650 further includes a plot 666 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50c having the s-polarization state 51 and incident at the third incident angle a3 on the comparative optical construction.

[0129] Referring to FIGS. 1, 4A, and 6A-6B, as is apparent from the graphs 600, 650, for the first incident signal 50a, 50b, 50c incident on the optical construction 300 in the first incident plane Pl, for each of the s- and p-polarization states 51, 52, for at least one frequency F2 in the frequency range extending from about 0.5 GHz to about 10 GHz, and for at least two of the first incident angle al, the second incident angle a2, and the third incident angle a3, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 of the optical construction 300 by at least 1 dB.

[0130] In some embodiments, for the first incident signal 50a, 50b, 50c incident on the optical construction 300 in the first incident plane Pl, for each of the s- and p-polarization states 51, 52, for the at least one frequency F2, and for the at least two of the first incident angle al, the second incident angle a2, and the third incident angle a3, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 of the optical construction 300 by at least 1.2 dB, at least 1.4 dB, at least 1.6 dB, at least 1.8 dB, at least 2 dB, at least 2.5 dB, at least 3 dB, at least 4 dB, at least 5 dB, at least 6 dB, at least 7 dB, at least 8 dB, at least 9 dB, or at least lOdB.

[0131] In some embodiments, for the first incident signal 50a, for the p-polarization state 52, for the first incident angle al of about 0 degree, and for the at least one frequency F2 of about 4 GHz, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 (indicated by tl in FIG. 6A) of the optical construction 300 by about 2.5 dB. Further, in some embodiments, for the first incident signal 50b, for the p-polarization state 52, for the first incident angle a2 of about 40 degrees, and for the at least one frequency F2 of about 4 GHz, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 (indicated by t2 in FIG. 6A) of the optical construction 300 by about 5.6 dB. Further, in some embodiments, for the first incident signal 50c, for the p-polarization state 52, for the first incident angle a3 of about 60 degrees, and for the at least one frequency F2 of about 4 GHz, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 (indicated by t3 in FIG. 6 A) of the optical construction 300 by about 8.6 dB.

[0132] In addition, in some embodiments, for the first incident signal 50a, for the s-polarization state 51, for the first incident angle al of about 0 degree, and for the at least one frequency F2 of about 4 GHz, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 (indicated by t4 in FIG. 6B) of the optical construction 300 by about 2.6 dB. Further, in some embodiments, for the first incident signal 50b, for the s-polarization state 51, for the first incident angle a2 of about 40 degrees, and for the at least one frequency F2 of about 4 GHz, the first and second meshes 40 of the optical construction 300, in combination, increase the transmission coefficient S21 (indicated by t5 in FIG. 6B) of the optical construction 300 by about 1.8 dB.

[0133] Further, it is apparent from the graphs 600, 650 that, in some embodiments, for the first incident signal 50a, 50b, 50c, for each of the s- and p-polarization states 51, 52, for at least one second frequency F2’ in the frequency range extending from about 0.25 GHz to about 5 GHz, and for each of the first, second, and third incident angles al, a2, a3, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, decrease the transmission coefficient S21 of the optical construction 300 by at least 2 dB.

[0134] In some embodiments, for the first incident signal 50a, 50b, 50c, for each of the s- and p- polarization states 51, 52, for the at least one second frequency F2’, and for each of the first, second, and third incident angles al, a2, a3, the two-dimensional meshes 40 of the electrically conductive first layers 40, in combination, decrease the transmission coefficient S21 of the optical construction 300 by at least 4 dB, at least 6 dB, at least 8 dB, or at least 10 dB.

[0135] In the illustrated graphs 600, 650, for the first incident signal 50a, 50b, 50c, for the at least one second frequency F2’, and for each of the first, second, and third incident angles al, a2, a3, the two- dimensional meshes 40 of the electrically conductive first layers 40, in combination, decrease the transmission coefficient S21 of the optical construction 300 by about 17 dB for the p-polarization state 52 and decrease the transmission coefficient S21 of the optical construction 300 by about 14 dB for the s- polarization state 51.

[0136] FIG. 7A shows a graph 700 depicting transmission coefficients S21 of the optical construction 300 (shown in FIG. 1) and the comparative optical construction versus frequency for the p-polarization state 52, according to yet another embodiment of the present disclosure.

[0137] FIG. 7B shows a graph 720 depicting transmission coefficients S21 of the optical construction 300 and the comparative optical construction versus frequency for the s-polarization state 51, according to yet another embodiment of the present disclosure.

[0138] In some embodiments, the optical construction 300 may include three substantially parallel two- dimensional metallic meshes 40 and the at least one electrically insulative substrate 30 is disposed between two of the three meshes 40. In an exemplary embodiment, the optical construction 300 may include the altematingly stacked meshes 40 and the substrates 30, such that one of the meshes 40 is disposed between two substrates 30 and two meshes 40 are disposed at outer surfaces of the two substrates 30. In some embodiments, the meshes 40 may have different cell pitches (e.g., the cell pitch Ml and the cell pitch M2). For instance, the mesh 40 disposed between the substrates 30 may have the pitch of 16 mm, and the meshes 40 disposed on the outer surfaces of the substrate 30 may have the pitch of 32 mm.

[0139] FIG. 7 A shows the graph 700 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signals 50a, 50b, 50c having the p-polarization state 52 and incident on the optical construction 300, and the transmission coefficient S21 of the comparative optical construction for the first incident signals 50a, 50b, 50c having the p-polarization state 52 and incident on the comparative optical construction.

[0140] FIG. 7B shows the graph 720 depicting the transmission coefficients S21 of the optical construction 300 for the first incident signals 50a, 50b, 50c having the s-polarization state 51 and incident on the optical construction 300, and the transmission coefficients S21 of the comparative optical construction for the first incident signals 50a, 50b, 50c having the s-polarization state 51 and incident on the comparative optical construction.

[0141] Frequency is expressed in gigahertz (GHz) in the abscissa. The transmission coefficient S21 is expressed in decibels (dB) in the ordinate.

[0142] The graph 700 includes a plot 702 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the optical construction 300.

[0143] The graph 700 further includes a plot 704 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the optical construction 300.

[0144] The graph 700 further includes a plot 706 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3 on the optical construction 300.

[0145] The graph 700 further includes a plot 712 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the comparative optical construction.

[0146] The graph 700 further includes a plot 714 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the comparative optical construction.

[0147] The graph 700 further includes a plot 716 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3 on the comparative optical construction. The graph 720 includes a plot 722 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the s-polarizations state 51 and incident at the first incident angle al on the optical construction 300.

[0148] The graph 720 further includes a plot 724 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50b having the s-polarizations state 51 and incident at the second incident angle a2 on the optical construction 300.

[0149] The graph 720 further includes a plot 726 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50c having the s-polarizations state 51 and incident at the third incident angle a3 on the optical construction 300.

[0150] The graph 720 further includes a plot 732 depicting the transmission coefficient S21 of the comparative optical constmction for the first incident signal 50a having the s-polarizations state 51 and incident at the first incident angle al on the comparative optical construction.

[0151] The graph 720 further includes a plot 734 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50b having the s-polarizations state 51 and incident at the second incident angle a2 on the comparative optical construction.

[0152] The graph 720 further includes a plot 736 depicting the transmission coefficient S21 of the comparative optical constmction for the first incident signal 50c having the s-polarizations state 51 and incident at the third incident angle a3 on the comparative optical construction.

[0153] FIG. 7C shows a graph 750 depicting the transmission coefficients S21 of the optical construction 300 and the comparative optical constmction for the first incident signal 50a incident at the first incident angle al. Specifically, the graph 750 depicts the transmission coefficient S21 for a frequency range of about 4 GHz to about 6.6 GHz.

[0154] The graph 750 includes the plot 702 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the optical construction 300.

[0155] The graph 750 further includes the plot 722 depicting the transmission coefficient S21 of the optical construction 300 for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the optical construction 300.

[0156] The graph 750 further includes the plot 712 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the comparative optical construction.

[0157] The graph 750 further includes the plot 732 depicting the transmission coefficient S21 of the comparative optical construction for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the comparative optical construction.

[0158] The graph 750 shows the transmission coefficient S21 for continuous first and second frequency ranges 60, 61. Specifically, the graph 750 shows the transmission coefficient S21 for the continuous first frequency range 60 and the continuous second frequency range 61. Each of the continuous first and second frequency ranges 60, 61 is disposed between about 0.5 GHz to about 10 GHz. Each of the continuous first and second frequency ranges 60, 61 is at least 0.05 GHz wide. In some embodiments, each of the continuous first and second frequency ranges 60, 61 is at least 0.1 GHz wide, at least 0.15 GHz wide, at least 0.2 GHz wide, at least 0.25 GHz wide, at least 0.3 GHz wide, at least 0.35 GHz wide, at least 0.4 GHz wide, at least 0.45 GHz wide, or at least 0.5 GHz wide. In some embodiments, the continuous first frequency range 60 is about 0.4 GHz wide and the second frequency range 61 is about 0.25 GHz wide.

[0159] The continuous first and second frequency ranges 60, 61 are spaced apart from each other by at least 0.2 GHz (indicated by dl in FIG. 7C). In some embodiments, the continuous first and second frequency ranges 60, 61 are spaced apart from each other by at least 0.4 GHz, at least 0.6 GHz, at least 0.8 GHz, at least 1 GHz, at least 1.5 GHz, or at least 2 GHz. In some embodiments, the continuous first and second frequency ranges 60, 61 are spaced apart from each other by about 1 GHz.

[0160] For the substantially normally incident signal 50a, for at least one of the s- and p-polarization states 51, 52, and for the continuous first and second frequency ranges 60, 61 that are spaced apart from each other by at least 0.2 GHz and are each disposed between about 0.5 GHz to about 10 GHz and is at least 0.05 GHz wide, the optical constmction 300 has the transmission coefficient S21 of greater than about -1.6 dB (shown by a line 62).

[0161] In some embodiments, for the substantially normally incident signal 50a, for at least one of the s- and p-polarization states 51, 52, and for the continuous first and second frequency ranges 60, 61, the optical construction 300 has the transmission coefficient S21 of greater than about -1.5 dB, greater than about -1.4 dB, greater than about -1.3 dB, greater than about -1.2 dB, greater than about -1.1 dB, or greater than about -1 dB.

[0162] As is apparent from FIGS. 1, 4A, and 7A-7C, for the substantially normally incident signal 50a, for each of the s- and p-polarization states 51, 52, and for the continuous first and second frequency ranges 60, 61, the optical construction 300 has the transmission coefficient S21 of greater than about -1.6 dB.

[0163] FIG. 8A shows a graph 800 depicting transmission coefficients S21 of the window 300 (shown in FIG. 1) and a comparative window versus frequency for the p-polarization state 52, according to an embodiment of the present disclosure.

[0164] FIG. 8B shows a graph 820 depicting transmission coefficients S21 of the window 300 and the comparative window versus frequency for the s-polarization state 51, according to an embodiment of the present disclosure.

[0165] It is to be noted that the comparative window is similar to the window 300 and includes the plurality of substrates 30, however, the comparative window does not include the plurality of meshes 40.

[0166] In some embodiments, the window 300 may include the plurality of substrates 30 and the substantially parallel two-dimensional meshes 40. In some embodiments, the substantially parallel two- dimensional meshes 40 may have three meshes 40 having different cell pitches (e.g., the cell pitch Ml and the cell pitch M2). In an exemplary embodiment, the three meshes 40 may have the cell pitches of about 10.4 mm, 13 mm, and 17.3 mm, respectively.

[0167] FIG. 8A shows the graph 800 depicting the transmission coefficient S21 of the window 300 for the first incident signals 50a, 50b, 50c having the p-polarization state 52 and incident on the window 300, and the transmission coefficient S21 of the comparative window for the first incident signals 50a, 50b, 50c having the p-polarization state 52 and incident on the comparative window.

[0168] FIG. 8B shows the graph 820 depicting transmission coefficient S21 of the window 300 for the first incident signals 50a, 50b, 50c having the s-polarization state 51 and incident on the window 300, and the transmission coefficient S21 of the comparative window for the first incident signals 50a, 50b, 50c having the s-polarization state 51 and incident on the comparative window.

[0169] Frequency is expressed in gigahertz (GHz) in the abscissa. The transmission coefficient S21 is expressed in decibels (dB) in the ordinate.

[0170] The graph 800 includes a plot 802 depicting the transmission coefficient S21 of the window 300 for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the window 300.

[0171] The graph 800 further includes a plot 804 depicting the transmission coefficient S21 of the window 300 for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the window 300.

[0172] The graph 800 further includes a plot 806 depicting the transmission coefficient S21 of the window 300 for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3 on the window 300.

[0173] The graph 800 further includes a plot 812 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al on the comparative window.

[0174] The graph 800 further includes a plot 814 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50b having the p-polarization state 52 and incident at the second incident angle a2 on the comparative window.

[0175] The graph 800 further includes a plot 816 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3 on the comparative window.

[0176] The graph 820 includes a plot 822 depicting the transmission coefficient S21 of the window 300 for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the window 300.

[0177] The graph 820 further includes a plot 824 depicting the transmission coefficient S21 of the window 300 for the first incident signal 50b having the s-polarization state 51 and incident at the second incident angle a2 on the window 300.

[0178] The graph 820 further includes a plot 826 depicting the transmission coefficient S21 of the window 300 for the first incident signal 50c having the s-polarization state 51 and incident at the third incident angle a3 on the window 300.

[0179] The graph 820 further includes a plot 832 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50a having the s-polarization state 51 and incident at the first incident angle al on the comparative window. The graph 820 further includes a plot 834 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50b having the s-polarization state 51 and incident at the second incident angle a2 on the comparative window.

[0180] The graph 820 further includes a plot 836 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50c having the s-polarization state 51 and incident at the third incident angle a3 on the comparative window.

[0181] As is apparent from FIGS. 1, 4A, and 8A-8B, for the first incident signal 50a, 50b, 50c incident on the window 300 in the first incident plane Pl, for at least one of the s- and p-polarization states 51, 52, for each frequency in a continuous first frequency range 63 that is at least 0.25 GHz wide and is disposed within the frequency range extending from about 0.5 GHz to about 10 GHz, and for each of the first incident angle al, the second incident angle a2, and the third incident angle a3, the three meshes 40 of the window 300, in combination, increase the transmission coefficient S21 of the window 300 by at least 1 dB while reducing the optical transmission of the window 300 by less than about 20% for the at least one visible wavelength between about 420 nm and about 680 mu.

[0182] In some embodiments, for the first incident signal 50a, 50b, 50c incident on the window 300 in the first incident plane Pl, for the at least one of the s- and p-polarization states 51, 52, for each frequency in the continuous first frequency range 63, and for each of the first incident angle al, the second incident angle a2, and the third incident angle a3, the three meshes 40 of the window 300, in combination, increase the transmission coefficient S21 of the window 300 by at least 1.5 dB, at least 2 dB, at least 3 dB, at least 3.5 dB, at least 4 dB, at least 5 dB, or at least 10 dB, while reducing the optical transmission of the window 300 by less than about 20% for at least one visible wavelength between about 420 nm and about 680 nm.

[0183] In some embodiments, for the first incident signal 50a, 50b, 50c incident on the window 300 in the first incident plane Pl, for the p-polarization state 52, for each frequency in the continuous first frequency range 63 that is 0.8 GHz wide, and for each of the first incident angle al of about 0 degrees, the second incident angle a2 of about 40 degrees, and the third incident angle a3 of about 60 degrees, the three meshes 40 of the window 300, in combination, increase the transmission coefficient S21 of the window 300 by at least 1 dB while reducing the optical transmission of the window 300 by less than about 20% for at least one visible wavelength between about 420 nm and about 680 nm.

[0184] In some embodiments, the continuous first frequency range 63 is at least 0.3 GHz wide, at least 0.35 GHz wide, at least 0.4 GHz wide, at least 0.45 GHz wide, at least 0.5 GHz wide, at least 0.55 GHz wide, at least 0.6 GHz wide, at least 0.65 GHz wide, at least 0.7 GHz wide, at least 0.8 GHz wide, at least 0.9 GHz wide, or at least 1 GHz wide. In illustrated embodiment of FIG. 8A, the first continuous frequency range 63 is about 0.8 GHz wide.

[0185] In some embodiments, for the first incident signal 50a having the p-polarization state 52 and incident at the first incident angle al, the transmission coefficient S21 is increased (as indicated by ul in FIG. 8A) by about 3 dB, for the first incident signal 50b incident having the p-polarization state 52 and incident at the second incident angle a2, the transmission coefficient S21 is increased (as indicated by u2 in FIG. 8A) by about 6.5 dB, and for the first incident signal 50c having the p-polarization state 52 and incident at the third incident angle a3, the transmission coefficient S21 is increased (as indicated by u3 in FIG. 8A) by about 7.2 dB, while reducing the optical transmission of the window by less than about 20% for at least one visible wavelength between about 420 nm and about 680 nm.

[0186] FIG. 8C shows a graph 850 depicting the transmission coefficients S21 of the optical window 300 and the transmission coefficient S21 of the comparative window for the first incident signal 50a incident at the first incident angle al.

[0187] The graph 850 includes the plot 802 depicting the transmission coefficient S21 of the optical window 300 for the first incident signal 50a having the p-polarizations state 52 and incident at the first incident angle al on the optical window 300.

[0188] The graph 850 further includes the plot 822 depicting the transmission coefficient S21 of the optical window 300 for the first incident signal 50a having the s-polarizations state 51 and incident at the first incident angle al on the optical window 300.

[0189] The graph 850 further includes the plot 812 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50a having the p-polarizations state 52 and incident at the first incident angle al on the comparative window.

[0190] The graph 850 further includes the plot 832 depicting the transmission coefficient S21 of the comparative window for the first incident signal 50a having the s-polarizations state 51 and incident at the first incident angle al on the comparative window.

[0191] In some embodiments, for the first incident angle al, for each of the s- and p-polarization states 51, 52, and for a continuous second frequency range 64 that is at least 0.5 GHz wide and is disposed within a frequency range extending from about 1 GHz to about 7 GHz, the optical window 300 has the transmission coefficient S21 of greater than about -3 dB (shown by a line 65).

[0192] In some embodiments, the continuous second frequency range 64 is at least 0.6 GHz wide, at least 0.7 GHz wide, at least 0.8 GHz wide, at least 0.9 GHz wide, at least 1 GHz wide, at least 1.1 GHz wide, at least 1.2 GHz wide, at least 1.5 GHz wide, or at least 2 GHz wide. In the illustrated embodiment of FIG. 8C, the continuous second frequency range 64 is about 1.3 GHz wide.

[0193] In some embodiments, for the first incident angle al, for each of the s- and p-polarization states 51, 52, and for the continuous second frequency range 64 that is at least 0.5 GHz wide, the window 300 has the transmission coefficient S21 of greater than about -2.5 dB, greater than about -2 dB, greater than about - 1.5 dB, greater than about -1 dB, or greater than about -0.5 dB.

[0194] FIG. 9A shows a schematic view of a building 900, according to an embodiment of the present disclosure. The building 900 includes a building window 910. The building window 910 includes the multilayer optical window 300 in FIG 1.

[0195] FIG. 9B shows a schematic view of a vehicle 920, according to another embodiment of the present disclosure. The vehicle 920 includes a vehicle window 930. The vehicle window 930 includes the multilayer optical window 300 shown in FIG 1.

[0196] Referring to FIGS. 1-9B, the optical construction 300 may improve the RF wave transmission of the electrically insulative second layers 30 (i.e., electrically thick dielectric materials and composites) for a wide range of angles (e.g., the first, second, and third incident angles al, a2, a3) and operating frequencies (e.g., the frequency range extending from about 0.5 GHz to about 10 GHz) using one or several of the electrically conductive two-dimensional meshes 40 in the optical construction 300.

[0197] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0198] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

CLAIMS1. An optical construction comprising a plurality of alternating electrically conductive first and electrically insulative second layers stacked along a thickness direction of the optical construction, at least two of the layers in the first and the second layers defining an air gap therebetween, each of the electrically conductive first layers comprising an electrically conductive two-dimensional mesh, the mesh comprising a plurality of electrically conductive traces connected to define a plurality of enclosed open areas, the mesh having a percent open area of greater than about 20% and an effective sheet resistance of less than about 10 ohms per square, such that for a first incident signal incident on the optical construction in a first incident plane, for each of s- and p-polarization states, for at least one frequency in a frequency range extending from about 0.5 GHz to about 10 GHz, and for each of a first incident angle of less than about 10 degrees and a second incident angle of greater than about 20 degrees and less than about 60 degrees, the two-dimensional meshes of the electrically conductive first layers, in combination, increase a transmission coefficient S21 of the optical construction by at least 1 dB.

2. The optical construction of claim 1, wherein any two neighboring meshes in the plurality of meshes are spaced apart by at least 1 mm.

3. The optical construction of claim 1, wherein for a substantially normally incident light, for each of mutually orthogonal first and second polarization states, and for at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm, the optical construction has a total optical transmittance of at least about 20%.

4. The optical construction of claim 1, wherein for the first incident signal, for the p-polarization state, for the at least one frequency, and for each of the first and the second incident angles, the two-dimensional meshes of the electrically conductive first layers, in combination, increase a transmission coefficient S21 of the optical constmction by at least 2 dB.

5. The optical construction of claim 1, wherein for the first incident signal, for the at least one frequency, and when the incident angle increases from the first incident angle to the second incident angle, the two-dimensional meshes of the electrically conductive first layers, in combination, increase the transmission coefficient S21 of the optical construction for the p-polarization state and decrease the transmission coefficient S21 of the optical construction for the s-polarization state.

6. The optical construction of claim 5, wherein the increase is at least 1 dB and the decrease is at least7. The optical construction of claim 1, wherein for the first incident signal, for each of the s- and p- polarization states, for at least one second frequency in a frequency range extending from about 0.25 GHz to about 5 GHz, and for each of the first and second incident angles, the two-dimensional meshes of the electrically conductive first layers, in combination, decrease the transmission coefficient S21 of the optical construction by at least 2 dB.

8. An optical construction comprising: substantially parallel two-dimensional electrically conductive first and second meshes defining an air gap therebetween, each of the first and second meshes comprising a plurality of electrically conductive traces connected to form a plurality of regularly arranged cells, the first and second meshes having different cell pitches along a same in-plane first direction; and at least one electrically insulative substrate disposed between the first and second meshes, the at least one substrate, the air gap, and the first and second meshes substantially co-extensive with one another in width and length, an average thickness of the air gap being greater than an average thickness of at least one of the substrates in the at least one substrate; such that, for a first incident signal incident on the optical construction in a first incident plane, for each of s- and p-polarization states, for at least one frequency in a frequency range extending from about 0.5 GHz to about 10 GHz, and for at least two of a first incident angle of less than about 10 degrees, a second incident angle of greater than the first incident angle by at least 20 degrees, and a third incident angle of greater than the second incident angle by at least 5 degrees, the first and second meshes of the optical construction, in combination, increase a transmission coefficient S21 of the optical construction by at least 1 dB.

9. The optical construction of claim 8, wherein for the first incident signal, for each of the s- and p- polarization states, for at least one second frequency in a frequency range extending from about 0.25 GHz to about 5 GHz, and for each of the first, the second, and the third incident angles, the two-dimensional meshes of the electrically conductive first layers, in combination, decrease the transmission coefficient S21 of the optical constmction by at least 2 dB.

10. An optical construction comprising: substantially parallel two-dimensional first, second, and third metallic meshes defining one or more air gaps therebetween, each of the three meshes comprising a plurality of metal traces connected to form a plurality of enclosed open areas and a percent open area of greater than about 20%; and at least one electrically insulative substrate disposed between two of the three metallic meshes, the at least one substrate, the one or more air gaps, and the three metallic meshes substantially co-extensive with one another in width and length; such that, for a substantially normally incident signal, for at least one of s- and p-polarization states, and for continuous first and second frequency ranges that are spaced apart from each other by at least 0.2GHz and are each disposed between about 0.5 GHz to about 10 GHz and is at least 0.05 GHz wide, the optical construction has a transmission coefficient S21 of greater than about -1.6 dB.

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