Curved optical devices and methods for making same

Abstract

A curved variable transmission optical device ("VTOD") includes a first substrate structure including a first transparent electrode provided on a first substrate and a second substrate structure including a second transparent electrode provided on a second substrate. The VTOD includes electro-optical material provided between the substrates, with each transparent electrode interposed between its respective substrate and the electro-optical material. The first and second substrate structures maintain a curved shape such that the VTOD is characterized by at least a first curvature. At least one transparent electrode includes a transparent hybrid conductor having a multilayer or gradient composition structure. The transparent hybrid conductor includes a conductive polymer and may further include an auxiliary conductor.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority and any other benefit of U.S. Provisional Patent Application No. 63 / 422,435, entitled CURVED OPTICAL DEVICES, AND METHODS FOR MAKING SAME, filed November 4, 2022, the entire disclosure of which is hereby incorporated by reference in its entirety.

[0002] FIELD OF THE DISCLOSURE The present disclosure relates to optical devices, and in particular to optical devices that include curved or multi-curved liquid crystal film structures. [Background technology]

[0003] Liquid crystal ("LC") electronic devices are optical devices that offer a low-cost, low-power approach to active light management. While LC electronic devices are known for their use in displays, LC devices can also be used to create light-adjusting (sometimes called light-adapting) windows, lenses, visors, eyeglasses, mirrors, and the like. For such applications, it is common for them to contain some degree of curvature. Whether freestanding or stacked, LC electronic devices for light management may need to assume a desired curved shape. It is common practice to fabricate light-managing LC devices using flat substrates. Unfortunately, conforming or transforming flat devices into curved, especially multi-curved, configurations is challenging because, among other reasons, meeting topographical requirements may require changes in area. Changing the overall surface area, for example, by stretching, can damage the device. Alternatively, one can start with a preformed curved substrate, but the finished LC device is more difficult to fabricate, in part due to the complexity of uniformly applying the various device layers to the curved substrate. Furthermore, starting from a pre-formed curved substrate may require specific molds for each application, i.e., each light-managed LC electronic device product must be individually tailored to account for unique product characteristics, e.g., curvature, size, etc. One product line may not be compatible with another.

[0004] Therefore, there is a need for curved or multi-curved optical devices, such as LC devices, that are easily manufactured and maintain high device performance quality. Summary of the Invention

[0005] According to one embodiment, a curved variable transmission optical device ("VTOD") includes a first substrate structure including a first transparent electrode provided on a first substrate and a second substrate structure including a second transparent electrode provided on a second substrate. The VTOD includes electro-optical material provided between the substrates, with each transparent electrode interposed between its respective substrate and the electro-optical material. The first and second substrate structures maintain a curved shape such that the VTOD is characterized by at least a first curvature. At least one transparent electrode includes a transparent hybrid conductor having a multilayer or gradient structure. The transparent hybrid conductor includes a conductive polymer.

[0006] According to another embodiment, a method for fabricating a curved VTOD includes providing a substantially planar VTOD in association with a molding device, and applying heat, force, or both heat and force to the substantially planar VTOD and first and second substrate precursor structures to permanently change shape in accordance with the molding device to form a curved VTOD having at least a first curvature. The substantially planar VTOD may include a first substrate precursor structure having a first transparent electrode material provided on a substantially planar first flexible substrate, and a second substrate precursor structure having a second transparent electrode material provided on a substantially planar second flexible substrate. A cell gap may be provided between the substrate precursor structures, with each transparent electrode interposed between its respective flexible substrate and the cell gap. At least one transparent electrode material comprises a transparent hybrid conductor having a multilayer or gradient composition structure. The transparent hybrid conductor comprises a conductive polymer. Heat, force, or both heat and force may be applied to the substantially planar VTOD to permanently change the shape of the first and second substrate precursor structures in accordance with the shaping device to form a curved VTOD having at least a first curvature.

[0007] According to another embodiment, a method for fabricating a curved substrate structure includes providing a substrate precursor structure in a molding apparatus, the substrate precursor structure including a transparent electrode material provided on a substantially planar flexible substrate. The transparent electrode material may include a transparent hybrid conductor having a multilayer or gradient composition structure. The transparent hybrid conductor may include a conductive polymer. Heat, force, or both heat and force may be applied to the substrate precursor structure to permanently change the shape of the substrate precursor structure in accordance with the molding apparatus to form a curved substrate structure characterized by at least a first curvature.

[0008] One or more embodiments of the present disclosure may provide curved optical devices and curved substrate structures that may have one or more of the following advantages: improved optical quality, improved electrical properties, improved uniformity across the device, and higher manufacturing yields. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional schematic diagram of a non-limiting example of a curved VTOD, according to some embodiments. [Figure 2] 1 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. [Figure 3A] 1 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. [Figure 3B] 1 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. [Figure 3C] 1 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. [Figure 3D] 1 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. [Figure 4] 1 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. [Figure 5A] 1A-1C are cross-sectional schematic diagrams of non-limiting examples of various curved VTODs, according to some embodiments. [Figure 5B] 1A-1C are cross-sectional schematic diagrams of non-limiting examples of various curved VTODs, according to some embodiments. [Figure 5C] 1A-1C are cross-sectional schematic diagrams of non-limiting examples of various curved VTODs, according to some embodiments. [Figure 5D] FIG. 1 is a perspective view of a non-limiting example of a curved VTOD, according to some embodiments. [Figure 6] 1 is a perspective view of a non-limiting example of a multi-curved surface, according to some embodiments. [Figure 7] 1 is a perspective view of a non-limiting example of a multi-curved surface and its projection onto a plane, according to some embodiments; FIG. [Figure 8A] 1 is a cross-sectional schematic diagram of a non-limiting example of a substantially planar VTOD, according to some embodiments. [Figure 8B] FIG. 1 is a perspective view of a non-limiting example of a substantially planar VTOD, according to some embodiments. [Figure 8C] 1 is a perspective view of a non-limiting example of a substantially planar VTOD associated with a molding apparatus, according to some embodiments. [Figure 9] 1A-1C are perspective views of non-limiting examples of curved VTODs that may be formed from substantially planar VTODs, according to some embodiments. [Figure 10] 1 is a schematic diagram of a non-limiting example of a molding apparatus, according to some embodiments. [Figure 11] FIG. 1 is a perspective view of a non-limiting example of a curved VTOD, according to some embodiments. [Figure 12] FIG. 1 is a block diagram outlining some non-limiting general steps for forming a curved VTOD, according to some embodiments. [Figure 13] FIG. 1 is a block diagram outlining some non-limiting general steps for forming a curved VTOD, according to some embodiments. [Figure 14] FIG. 1 is a block diagram outlining some non-limiting general steps for forming a curved VTOD, according to some embodiments. [Figure 15A]1A-1C are schematic top views of non-limiting examples of substrate precursor structures prior to stretching, according to some embodiments. [Figure 15B] FIG. 15B is a schematic top view of the structure from FIG. 15A after stretching, according to some embodiments. [Figure 16A] 1A-1C are schematic top views of non-limiting examples of substrate precursor structures prior to stretching, according to some embodiments. [Figure 16B] FIG. 16B is a schematic top view of the structure from FIG. 16A after stretching, according to some embodiments. [Figure 17A] 3A-3C are photographs from different angles of non-limiting examples of substrate precursor structures that have been stretched or thermoformed over a mold to form curved substrate structures, according to some embodiments. [Figure 17B] 3A-3C are photographs from different angles of non-limiting examples of substrate precursor structures that have been stretched or thermoformed over a mold to form curved substrate structures, according to some embodiments. [Figure 18] 1 is a map of sheet resistance across a curved substrate structure, with the left half representing data from Comparative Example A' and the right half representing data from Example 1'. [Figure 19] 10 is a histogram showing the distribution of counts for each sample within a particular sheet resistance range. DETAILED DESCRIPTION OF THE INVENTION

[0010] Curved VTOD Curved, light-adaptive eyeglasses, windows, mirrors, and the like may include one or more variable transmission optical devices (“VTODs”). FIG. 1 is a schematic cross-sectional view of a non-limiting example of a curved VTOD, according to some embodiments. For perspective, XYZ axes have been added to this and some other figures. The curved VTOD 10 can controllably affect incident light 26 such that transmitted light 27 is modulated or changed in some way (brightness, hue, polarization, direction, etc.). The curved VTOD 10 may include a pair of curved substrate structures, e.g., a first substrate structure 11 a and a second substrate structure 11 b. In some cases, the curvature may be measured relative to an axis or direction 70. The first substrate structure may include a first substrate 12 a and a first transparent electrode 14 a provided on the first substrate. The second substrate structure may include a second substrate 12 b and a second transparent electrode 14 b provided on the second substrate. The first and second substrate structures may be the same or different with respect to layer composition, thickness, or some other physical or chemical property. As discussed elsewhere herein, the substrates may be formed from materials that can be manipulated to assume and maintain a curved shape. In some embodiments, the substrates may comprise polymeric materials. The first and second substrates may be the same or different with respect to composition, thickness, or some other physical property. As discussed elsewhere herein, one or both transparent electrodes may have a multilayer or gradient composition structure and may comprise a transparent hybrid conductor including a conductive polymer. The first and second transparent conductors may be substantially the same or different with respect to composition, thickness, or some other physical or chemical property. For example, "substantially the same" in this context may correspond to a thickness or composition metric that is relatively within 30%, alternatively within 20% or 10%.

[0011] In some embodiments, optional alignment layers 18a, 18b may be provided on one or both transparent conductive layers. By way of non-limiting example, the alignment layers may comprise a polyimide material. In some embodiments, the alignment layers may be brushed as known in the art to aid in aligning an electro-optic material, such as a liquid crystal "LC" host, near the surface. In some embodiments, both alignment layers of a cell are rubbed. In some embodiments, a cell may include only one rubbed alignment layer.

[0012] Although not shown, one or both substrate structures may include additional layers. For example, a generally non-conductive passivation or insulating layer may optionally be provided on the transparent conductive layer. Such passivation layers may include, for example, polymers, non-conductive oxides, sol-gels, or composite materials. If an alignment layer is present, the passivation layer may be interposed between the transparent conductive layer and the alignment layer. In some embodiments, a sub-layer may optionally be provided between the substrate and the transparent conductive layer, for example, to increase adhesion between the transparent conductive layer and the substrate, to improve optical outcoupling, to increase scratch resistance, to act as a solvent barrier, or for some other reason. In some embodiments, the opposite side of the substrate (not having the transparent electrode) may also include one or more facing layers. In some cases, the sub-layer or the facing layer(s), or both, may include a hard coat layer to increase scratch resistance. However, in some embodiments, one or both substrate structures may exclude a hard coat, especially a hard coat made of a less flexible material such as an inorganic oxide.

[0013] In some embodiments, the curved VTOD 10 includes an electro-optic material 25, such as a liquid crystal guest-host mixture, provided between a pair of cell substrate substructures 11a, 11b. The electro-optic material may be capable of changing from a state of higher light transmittance to a state of lower light transmittance in a desired wavelength region, for example, when an electric field applied across the electro-optic material is changed. The electric field can be changed, for example, by changing the voltage applied between a pair of transparent electrodes 14a, 14b of the curved VTOD. The space or distance between the substrate structures defines a cell gap 20. To help maintain this separation, optional spacers (not shown), such as glass or plastic rods or beads, may be inserted or positioned between the substrates. In some embodiments, the cell gap may be in the range of 3 to 5 microns, 5 to 7 microns, 7 to 10 microns, 10 to 12 microns, 12 to 15 microns, 15 to 20 microns, 20 to 30 microns, 30 to 35 microns, 35 to 40 microns, or 40 to 50 microns, or any combination thereof. The curved VTOD cell may be surrounded by a sealing material 13, such as a UV curable optical adhesive or other sealant known in the art.

[0014] The transparent electrodes 14a, 14b may be electrically connected to a controller 15. The controller 15 may include one or more variable voltage sources, represented schematically by a circled V. FIG. 1 shows the VTOD power supply circuit with its switch 28 open so that no voltage is applied. When switch 28 is closed, a variable voltage or field may be applied across the liquid crystal guest-host mixture 25. In some embodiments, the voltage applied across the transparent conductive layers may be constant in polarity or amplitude for a period of time. In some embodiments, the voltage profile may vary or alternate with some frequency, such that for a period of time, the polarity applied to the first transparent electrode 14a is positive and the polarity applied to the transparent electrode 14b is negative, and for another period of time, the polarity is reversed so that the polarity applied to the transparent electrode 14a is negative and the polarity applied to the transparent electrode 14b is positive. This alternating polarity may take any type of waveform (sine, square, triangular, sawtooth, etc.) and may sometimes have a frequency less than about 200 Hz. In some cases, when alternating polarity is used, the frequency may range from about 30 to about 200 Hz. In some embodiments, the voltage applied between the electrodes may range from 0 to about 30 V.

[0015] In some embodiments, a light adaptive window or eyeglass system may include two or more stacked VTODs, as disclosed, for example, in International Application No. PCT / US22 / 44310, entitled "MULTI-COLOR VARIABLE TRANSMISSION OPTICAL DEVICE" (Soto et al.), filed September 22, 2022, the entire contents of which are incorporated herein by reference for all purposes. In some embodiments, a light adaptive window or eyeglass system may include passive optical features, such as lenses, polarizers, photochromic dyes, etc., that are generally not responsive to electronic controls.

[0016] Electro-optical materials Electro-optical materials are those that can change their optical absorption profile upon the application of an electric field. Electro-optical systems include electrochromic systems and liquid crystal (LC) systems. In some embodiments, the electro-optical material comprises a guest-host system having an LC host and, optionally, a dichroic (DC) dye dissolved, dispersed, or otherwise provided therein.

[0017] In some embodiments, guest-host systems can be used to generate electro-optical effects in which dichroism is tuned within a voltage-controllable liquid crystal cell. In an isotropic host, the molecules are randomly oriented and the effective absorption is a weighted average: α eff = (2α⊥ + α∥) / 3. In anisotropic LC host materials designed for polarization-independent operation, absorption can be adjusted by varying the α eff =(α⊥+α∥) / 2 or decrease it to α⊥.

[0018] In some embodiments, the liquid crystal guest-host comprises a mixture of a liquid crystal host and a dye material. The dye material may be characterized as having dichroic properties and may comprise a single dye or a mixture of dyes to provide these properties, as described below. In some embodiments, the liquid crystal guest-host mixture may be formulated as a "narrowband mixture" (e.g., resulting in a spectral absorption bandwidth having a full width at half maximum (FWHM) that is 175 nm or less) or a "broadband mixture" (e.g., resulting in a spectral absorption bandwidth that is greater than 175 nm).

[0019] LC Host In some cases, the LC host may have negative dielectric anisotropy ("negative LC") or positive dielectric anisotropy ("positive LC"). In some embodiments, the host comprises a chiral nematic or cholesteric liquid crystal material (collectively "CLC"). CLCs can be positive or negative, depending on the application. In some CLC embodiments, the liquid crystal material is cholesteric or comprises nematic liquid crystals combined with chiral dopants. CLC materials have a twisted or helical structure. The periodicity of the twist is referred to as its "pitch." The orientation or order of the liquid crystal host may be altered upon application of an electric field and may be used in combination with dye materials to control or partially control the optical properties of the cell. In some embodiments, CLC materials can be further characterized by their chirality, i.e., right-handed chirality or left-handed chirality.

[0020] A wide variety of LC materials, including CLCs, are available and have potential utility in various embodiments of the present disclosure. In some embodiments, the LC host may be nematic (zero chiral) or ferroelectric or smectic, and may have positive or negative dielectric anisotropy. Note that non-zero d / p may be achieved by using an appropriately rubbed surface, as is known in the art.

[0021] dye material When dichroic properties are desired, the dye material generally comprises at least one dichroic (DC) dye or a mixture of DC dyes. In some embodiments, the dye material may optionally further comprise a photochromic (PC) dye or a photochromic dichroic (PCDC) dye whose absorbance can be activated by exposure to UV light, such as sunlight. In some embodiments, the dye material may further comprise a small amount of a conventional absorbing dye, for example, to provide the device with a desired overall hue in the clear state.

[0022] DC dye Dichroic (DC) dyes typically have an elongated molecular shape and exhibit anisotropic absorption. Generally, absorption is higher along the long axis of the molecule, and such dyes may be referred to as "positive dyes" or dyes that exhibit positive dichroism. Positive DC dyes are generally used herein. However, in some cases, negative DC dyes that exhibit negative dichroism may be used instead. In some embodiments, the DC dyes (measured in the LC host) may have a dichroic ratio of at least 5.0, or at least 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0023] The level of visible light absorption by DC dyes can be a function of dye type and LC host. The apparent absorption of visible light can also be a function of voltage. The orientation or long-range order of the LC can also be a function of the electric field or voltage across the cell thickness. DC dyes exhibit some alignment with the LC host so that the application of a voltage can be used to change the apparent darkness (absorbance) or transparency (opacity) of the cell.

[0024] In some embodiments, the DC dye may comprise a small molecule-type material. In some embodiments, the DC dye may comprise an oligomeric or polymeric material. The chemical moiety responsible for light absorption may be, for example, a pendant group on the backbone. Multiple DC dyes may optionally be used, for example, to adjust the light absorption envelope or improve overall cell performance in terms of lifetime or some other property. The DC dye may also comprise functional groups that can improve solubility, miscibility, or bonding with the LC host. Some non-limiting examples of DC dyes may include azo dyes, for example, azo dyes having 2 to 10 azo groups, or alternatively, 2 to 6 azo groups. Other DC dyes, such as anthraquinone and perylene dyes, are known in the art. Molecules with dichroic properties may include, for example, those described in "Dyes as guests in ordered systems: current understanding and future directions" by Mark T. Sims (Pages 2363-2374) in Liquid Crystals, Volume 43, 2016, Issues 13-15.

[0025] Although VTOD devices have been described with respect to certain LC cells, the devices and methods of this disclosure may also be applied to other types of variable transmission optical devices, such as electrochromic devices, which may optionally include inorganic materials. In some embodiments, VTOD devices can not only change the transmission (hue, polarization, direction) of light, but can also change the reflectance of a light-regulating device.

[0026] substrate Referring again to FIG. 1 , in some embodiments, the VTOD substrates 12 a, 12 b may be independently selected and may comprise plastic, glass, ceramic, or some other material. In some embodiments, at least one substrate, or alternatively both substrates, comprises a material that can be manipulated from a first shape to assume and retain a second shape, e.g., a curved shape. Shape-retaining does not mean that the substrate or substrate structure is inflexible, but rather that the new shape is generally maintained when at rest in the absence of external forces. In some cases, such substrate materials may comprise polymeric materials. In some embodiments, the substrates may comprise plastic materials, including, but not limited to, thermoplastic materials. In some cases, the substrate material may be a thermosetting polymer, e.g., a polymer that is initially highly manipulable to form a new shape and can later be “cured” to generally retain that shape. Such curing may include heat, UV radiation, chemical treatment, or some other stimulus. As some non-limiting examples, the substrate may comprise (alone or in combination with other materials) polycarbonate (PC), blends of polycarbonate and copolymers, polyethersulfone (PES), polyethylene terephthalate (PET), cellulose triacetate (TAC), polyamide, p-nitrophenyl butyrate (PNB), polyetheretherketone (PEEK), polyethylene naphthalate (PEN), polyetherimide (PEI), polyarylate (PAR), polyvinyl acetate, cyclic olefin polymer (COP), polyester, polyurethane, polysilicone, polyacrylate, polypropylene, polyethylene, polystyrene, polyvinyl chloride, polylactic acid, ABS polymer, or any other polymeric material having desired properties. The substrate may also comprise a composite of materials, for example, a polymeric material combined with glass, ceramic, or other inorganic additives. In some embodiments, the substrate may have a transmittance of greater than 45%, alternatively greater than 50%, 60%, 70%, 80%, 90%, or 95% for visible radiation having wavelengths between 400 nm and 700 nm.In some embodiments, the substrate may have high optical clarity (low haze) so that a person can clearly see through the VTOD. In some embodiments, the support may optionally have several colors or shades. The substrate may include multiple materials or have a multilayer structure. In some embodiments, the thickness of the substrate may be in the range of 10 to 20 μm, 20 to 30 μm, 30 to 40 μm, 40 to 50 μm, 50 to 75 μm, 75 to 100 μm, 100 to 150 μm, 150 to 200 μm, 200 to 250 μm, 250 to 300 μm, 300 to 350 μm, 350 to 400 μm, 400 to 450 μm, 450 to 500 μm, 500 to 600 μm, 600 to 800 μm, 800 to 1000 μm, or greater than 1 mm, or any combination of these ranges.

[0027] transparent electrode "Visible light" generally refers to the wavelength range of about 400 nm to about 700 nm. A "transparent" electrode or conductive layer means that the conductive layer allows for an overall transmittance of at least 45% of incident visible light. A transparent electrode can absorb or reflect a portion of visible light and still be useful.

[0028] In some embodiments, at least one substrate structure may have a multilayer or gradient composition structure and may include a transparent hybrid conductor including a conductive polymer. Figure 2 is a cross-sectional schematic diagram of a non-limiting example of a transparent hybrid conductor, according to some embodiments. Substrate structure 211 may include a transparent substrate 212 and a transparent electrode, i.e., a transparent hybrid conductor 214, disposed on the substrate. For clarity, curvature is not illustrated. The hybrid conductor may include a multilayer or gradient composition structure. For example, hybrid conductor 214 may include a lower portion 231 adjacent to substrate 212 and an upper portion 233 overlying the lower portion and having a different composition. Although not shown, upper portion 233 may be adjacent to an electro-optical material, optionally with one or more intervening layers, such as alignment layers or passivation layers, as described with respect to Figure 1. In some embodiments, the two portions may be separate conductive layers. In some embodiments, the two portions may represent a compositionally gradient section such that the lower portion of the hybrid conductor (e.g., the lower 50%, 25%, or 10% measured from the bottom of the hybrid conductor) has a different material composition or percentage relative to the upper portion (e.g., the upper 50%, 25%, or 10% measured from the top of the hybrid conductor).

[0029] Whether gradient, separate layers, or some combination, "different composition" in this context means that the weight percent of at least one conductive agent in the upper portion (or layer) is different from the weight percent of the same conductive agent in the lower portion (or layer). Generally, a different composition is one in which the ratio of the weight percent of at least one conductive agent in the upper and lower portions is outside the range of 0.5 to 2.0. In some cases, the conductive agent used in the lower portion may be completely absent from the upper portion, which uses a different type of conductive agent, or vice versa.

[0030] The transparent hybrid conductor includes at least one conductive agent. In some preferred embodiments, the transparent hybrid conductor includes at least two different conductive agents. The conductive agent is a material that conducts electric charge and, in some cases, may have a conductivity of at least 0.1 S / cm. The conductive agent may, in some cases, be an intrinsically conductive polymer, including, but not limited to, PEDOT, such as PEDOT:PSS, poly(pyrrole), polyaniline, polyphenylene, or poly(acetylene). The conductive agent may, in some cases, be a metal, including, but not limited to, silver, copper, aluminum, titanium, iron, zinc, nickel, tungsten, cobalt, a transition metal, or an alloy. The conductive agent may, in some cases, be a metal oxide, such as a transparent conductive oxide (TCO), including, but not limited to, indium-doped tin oxide (ITO), aluminum-doped zinc oxide (AZO), and fluorine-doped tin oxide (FTO). The conductive agent may, in some cases, include a carbon-based material, such as carbon nanotubes (CNTs) or graphene.

[0031] In some cases, the conductive agent may be provided as a discontinuous layer or a continuous layer (if sufficiently transparent). In some cases, the conductive agent may be provided as particles dispersed in a transparent matrix. There is no particular limitation on the shape of such particles, which may be spherical, oval, cubic, flake, sheet, nanowire (NW), nanotube, or any combination thereof, or some other shape.

[0032] Hybrid conductors include conductive polymers with at least one conductive agent. In some embodiments, the conductive polymer includes an intrinsically conductive polymer as described above (e.g., PEDOT, such as PEDOT:PSS, poly(pyrrole), polyaniline, polyphenylene, or poly(acetylene), or mixtures thereof). In some embodiments, the conductive polymer may include a non-conductive polymer and at least one conductive agent other than the intrinsically conductive polymer, such as metal particles, metal NWs, TCO particles, or CNTs. Such conductive agents may be provided in a concentration sufficient to create an interconnected network of conductive particles in the non-conductive polymer matrix. In some embodiments, the conductive polymer may include both the intrinsically conductive polymer and another conductive agent, such as metal particles, metal NWs, TCO particles, or CNTs, dispersed (uniformly or nonuniformly) therein.

[0033] In some embodiments, the conductive polymer is flexible and can be stretched at least 40%, or alternatively at least 50%, 60%, 70%, 80%, 90% in at least one direction and still maintain its electrical functionality within the hybrid conductor, e.g., its average resistance may increase by less than 10 times, or alternatively less than 5 times or 2 times upon such stretching.

[0034] 3A-3E and 4 are cross-sectional views of some non-limiting embodiments of transparent hybrid conductors, according to some embodiments. As with FIG. 2, curvature is not illustrated for clarity.

[0035] In FIG. 3A, substrate structure 311a includes a transparent hybrid conductor 314a provided on substrate 312. In this embodiment, hybrid conductor 314a has a multilayer structure and includes a first (or lower) conductive layer 331a and a second (or upper) conductive layer 333a. The first and second conductive layers have different compositions. Although they are shown as separate layers, in some cases there may be some intermixing at the interface. Note that the multilayer structure includes at least two separate layers in cross section in at least some portions of the substrate structure. The multilayer structure may have three or even more layers in some embodiments.

[0036] In some embodiments, both the first and second conductive layers are independently selected conductive polymers (first and second conductive polymer layers). In some cases, at least one conductive polymer layer comprises an auxiliary conductor material. An "auxiliary conductor" material is a conductive material selected from conductive agents other than intrinsically conductive polymers. In some cases, at least one conductive polymer layer comprises an intrinsically conductive polymer, which may optionally further comprise an auxiliary conductor.

[0037] In some embodiments, the second conductive layer 333a is a conductive polymer, and the first conductive layer 331a is not a conductive polymer. In such embodiments, the first conductive layer includes an auxiliary conductor, such as a TCO (solid layer, discontinuous layer, or particles), a thin metal layer, metal particles, metal nanowires, CNTs, or graphene. Although a relatively small amount of polymer binder may be present, the first conductive layer in this embodiment may have low extensibility and may not have the flexibility of a conductive polymer. In some cases, the second conductive layer (conductive polymer) may include an intrinsically conductive polymer and optionally further include an auxiliary conductor.

[0038] In some embodiments, the first conductive layer 331a is a conductive polymer, and the second conductive layer 333a is not a conductive polymer. In such embodiments, the second conductive layer includes an auxiliary conductor, such as a TCO (solid layer, discontinuous layer, or particles), a thin metal layer, metal particles, metal nanowires, CNTs, or graphene. Although a relatively small amount of polymer binder may be present, the second conductive layer in this embodiment may have low extensibility and may not have the flexibility of a conductive polymer. In some cases, the first conductive layer (conductive polymer) may include an intrinsically conductive polymer material and optionally further include an auxiliary conductor.

[0039] 3B shows another substrate structure 311b having a transparent hybrid conductor 314b disposed on a substrate 312. The hybrid conductor 314b may include a conductive polymer with a gradient composition structure. For example, the upper portion 333b may include less of a particular conductive agent than the lower portion 331b. The gradient may be smooth (as shown), more localized, or may have a composition midpoint closer to or farther from the substrate than shown in FIG. 3B.

[0040] 3C shows another substrate structure 311c having a transparent hybrid conductor 314c disposed on a substrate 312. The transparent hybrid conductor 314c can be characterized as a bilayer or gradient structure, with a lower portion 331c comprising a conductive polymer and an upper portion 333c comprising a conductive polymer material 341 in addition to an auxiliary conductor 343, e.g., in the form of particles, nanowires, or nanotubes. There is not necessarily a defined boundary between the upper and lower portions, although in some cases they may be separate layers. In another embodiment (not shown), the auxiliary conductor can instead be in the lower portion.

[0041] FIG. 3D shows another substrate structure 311d having a transparent hybrid conductor 314d disposed on a substrate 312. The transparent hybrid conductor may have a multilayer structure characterized by a conductive polymer 341d provided over and between segments of auxiliary conductors 343d disposed on a portion of the substrate 312. In cross section, the upper portion 333d of the transparent hybrid conductor 314d (which contains little auxiliary conductor) has a different composition than the lower portion 331d (which contains auxiliary conductor). Substrate structure 311d illustrates an embodiment in which the transparent hybrid conductor is not necessarily flat, although in some other embodiments (not shown), the conductive polymer 341d can be planarized and have a generally planar surface. In some embodiments, the auxiliary conductors 343b may be sections of TCO that have been divided into segments during drawing. In some embodiments, the auxiliary conductors 343d may represent metal nanowires or CNTs. In some embodiments, conductive polymer 341d may comprise an intrinsically conductive polymer and may optionally further comprise another auxiliary conductor material, which may be the same as or different from the material used in 343d.

[0042] 4 shows a substrate structure 411 having a transparent hybrid conductor 414 disposed on a substrate 412. The transparent hybrid conductor 414 may have a multilayer structure having a bottom conductive layer 431, a top conductive layer 433, and a middle conductive layer 432 interposed between the top and bottom conductive layers. At least one of the top, bottom, or middle conductive layers is a conductive polymer; alternatively, at least two, or even all three layers may be conductive polymers. Any of the conductive layer options discussed elsewhere herein may be applied to the middle layer.

[0043] In some embodiments, the hybrid conductor may include materials other than the conductive material, such as binders, elastomers, coating aids, adhesives, surfactants, or even small amounts of solvents such as water or organic solvents.

[0044] In some embodiments, one substrate structure may be the same or different from the other substrate structure in terms of materials, properties, layer structure, etc. In some embodiments, both substrate structures may include transparent hybrid conductors. In some cases, one substrate includes a transparent hybrid conductor and the other substrate structure uses a non-hybrid conductive polymer as its transparent electrode, or alternatively, no conductive polymer at all but a low-flexibility layer of, for example, TCO, metal nanowires, graphene, or carbon nanotubes.

[0045] curvature According to some embodiments, the curved VTOD may have at least one curvature along a first direction (first curvature). Referring again to FIG. 1 , the curved VTOD may have a first curvature relative to axis 70. The curvature may be measured from the surface of one of the substrate structures. In some cases, the curvatures of each substrate structure may generally match, but in some cases, there may be some difference as long as the cell gap does not change outside of the desired range. There are no particular limitations on the shape of the curvature. In some cases, the curved VTOD may include only one curvature. In some embodiments, the curved VTOD may have alternative or complex curvatures, even in just one dimension, than those shown in FIG. 1 . FIGS. 5A-5C are cross-sectional schematic diagrams of non-limiting examples of various curved VTODs according to some embodiments. In FIG. 5A, the curved VTOD 500A may form a nearly perfect ellipse in cross section. In FIG. 5B, the curved VTOD 500B may have a substantially flat portion in cross section and significant curves at the edges. In Figure 5C, the curved VTOD 500C may have an undulating or wavy curvature in cross section. Many other curvatures can be created. Figure 5D is a perspective view of a curved VTOD 500D with a complex asymmetric curvature. Grid lines have been added to the illustration to help show the topography.

[0046] In some embodiments, the curved VTOD may have a polycurved surface. As used herein, "polycurved surface" refers to a non-planar shape having compound curves, also referred to as a non-developable shape, which may include, but is not limited to, spherical, aspherical, and toroidal surfaces with different curvatures along two orthogonal axes (horizontal and vertical axes), for example, a toroidal shape, an oblate spheroid, an oblate spheroid, a prolate spheroid, or a saddle shape or surface with opposite principal curvatures along two orthogonal planes, for example, a horse or monkey saddle. Other examples of polycurved surfaces include, but are not limited to, elliptical hyperboloids, hyperbolic paraboloids, and spherocylindrical surfaces, where the polycurved surface may have constant or varying radii of curvature. A polycurved surface may also include segments or portions of such surfaces, or may be composed of a combination of such curves and surfaces. In some embodiments, a polycurved surface may have radii of curvature along two orthogonal axes. In various embodiments, a polycurved surface may be symmetric or asymmetric.

[0047] There are many ways to characterize a single or multi-curved surface. With reference to FIG. 6 , curved surface 662 may be characterized as having a first curvature 662-1 with a first height H1 and a first length L1 measured along a first direction, with a first curvature ratio C1 = H1 / L1. If curved surface 662 is a multi-curved surface (as shown here), the multi-curved surface may be further characterized as having a second curvature 662-2 with a second height H2 and a second length L2 measured along a second direction different from the first direction, with a second curvature ratio C2 = H2 / L2. In some embodiments, the second direction may be orthogonal to the first direction. The first curvature may be the same or different from the second curvature. In some embodiments, such as shown in FIG. 6 , L1 and L2 may correspond to the overall point-to-point length corresponding to the curved surface VTOD. In some embodiments, L1 and L2 may instead correspond to portions of a polysurface defining the length between inflection points in the curve. In some embodiments, one or both C1 and C2 may be greater than zero, and at least one or optionally both of C1 and C2 are less than 10, 5, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.05, 0.02, 0.01, 0.005, 0.002, or 0.001. Alternatively, the curvature at any point may be described in terms of a local "diopter," defined as D=0.5 / R, where R is the radius of curvature in any one direction at the point measured in meters. In some cases, D in any one direction may be less than or equal to 20, 15, 10, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, or 0.2.

[0048] In some embodiments, the multi-curved surface 662 may be characterized by a first curvature 662-1 curved to a first value greater than 0 diopters and a second curvature 662-2 curved along a different axis than the first curvature to a second value greater than 0 diopters. In some embodiments, the second curvature may be orthogonal to the first curvature. One or both of the first and second values ​​may be less than 20, 15, 10, 8, 6, 5, 4, 3, 2, or 1.

[0049] 7 , in some embodiments, surface area 762A of multi-curved surface 762 may be greater than virtual area 762V defined by the projection of the multi-curved surface onto a virtual plane. In some embodiments, surface area 762A may be greater than or equal to 0.1-0.2%, 0.2-0.3%, 0.3-0.4%, 0.4-0.5%, 0.5-0.6%, 0.6-0.7%, 0.7-0.8%, 0.8-1.0%, 1.0-1.2%, 1.2-1.4%, 1.4-1.6%, 1.6-1.8%, 1.8-2.0%, 2.0-2.5%, 2.5-3.0%, 3.0-3.5%, 3.5-4.0%, 4.0-4.5%, 5.0-5.5%, 6.0-6.5%, 7.0-7.5%, 8.0-8.5%, 9.0-9.5%, 10.0-10.5%, 11.0-11.5%, 12.0-12.5%, 13.0-14.5%, 14.0-15.5%, 15.0-16.5%, 16.0-17.5%, 17.0-18.5%, 18.0-19.5%, 19.0-20.5%, 20.0-21.5%, 21.0-22.5%, 22.0-23.0%, 23.0-24.0%, 25.0-26.0%, 26.0-27.0%, 27.0-28.0%, 28.0-29.0%, 29.0-30.0%, 30.0-31.0%, 31.0-32.0%, 32 The range may be greater than 0.5%, 4.5-5%, 5-6%, 6-7%, 7-8%, 8-9%, 9-10%, 10-11%, 11-12%, 12-13%, 13-14%, 14-15%, 15-20%, 20-30%, 30-40%, 40-50%, 50-75%, 75-100%, 100-125%, 125-150%, 150-200%, 200-300%, 300-400%, or any combination thereof.

[0050] Method for making curved VTOD In some embodiments, forming a curved VTOD can begin with a substantially planar VTOD, which can be considered a curved VTOD precursor. FIG. 8A is a cross-sectional schematic diagram of a non-limiting example of a substantially planar VTOD according to some embodiments, and FIG. 8B is a perspective view. Except for its substantially planar nature, the properties, materials, and layer structures discussed with respect to a curved VTOD can generally be employed for a substantially planar VTOD. By "substantially planar," we mean that the device or substrate, in the absence of an applied force, has less than the desired curvature of the intended curved VTOD. In some cases, a substantially planar component may naturally lie flat relative to a plane, but may have some curl or curvature. In some embodiments, the substantially planar component has less than 75%, alternatively, less than 50%, 40%, 30%, 20%, 15%, 10%, or 5% of the desired curvature of the curved VTOD in at least one dimension. The substantially planar VTOD 810 may include a first substrate precursor structure 811a, which may include a first transparent electrode material 814a provided on a substantially planar first flexible substrate 812a. The substantially planar VTOD 810 may further include a second substrate precursor structure 811b, which may include a second transparent electrode material 814b provided on a substantially planar second flexible substrate 812b. The first and second substrates may extend in a plane generally parallel to a plane defined by a first direction 870 and a second direction 872 (FIG. 8B). One or both transparent electrode materials may include hybrid conductors, as discussed elsewhere herein. Similarly, the materials and properties of the substrates may be as described elsewhere herein. In some embodiments, optional alignment layers 818a, 818b may be provided on one or both transparent conductive layers.

[0051] While a curved VTOD can be a desirable product, it is often difficult to uniformly apply a layer, such as a transparent electrode, onto a non-planar substrate. Many coating and deposition methods are better suited to deposition onto a relatively flat target. Therefore, in some embodiments, it can be useful to start with a substantially planar substrate onto which additional layers are coated.

[0052] Referring again to FIG. 8A , the space between the substrate structures defines a cell gap 820. Optional spacers (not shown), such as glass or plastic rods or beads, may be provided between the substrates to help maintain separation. In some embodiments, the space may contain an electro-optic material 825, for example, a liquid crystal guest-host mixture. However, when creating a curved VTOD, the substantially planar VTOD may, in some cases, not include the electro-optic material until after the curvature is formed. That is, in some cases, the electro-optic material may be provided later. The substantially planar VTOD may be surrounded or partially surrounded by a sealing material 813, such as a UV-curable optical adhesive or other sealant known in the art. In some cases, the substantially planar VTOD may be only partially surrounded so that it can be later filled with the electro-optic material. In some embodiments, the space may be filled with a temporary fluid that is later replaced by the electro-optic material after the curvature is formed.

[0053] In some embodiments, a substantially planar VTOD may be provided in association with a molding apparatus that can act on the substantially planar VTOD to form a curved VTOD. FIG. 8C is a perspective view similar to that of FIG. 8B , but in which the substantially planar VTOD 810 is associated with (e.g., disposed within) a molding apparatus 880. The molding apparatus 880 can act on the substantially planar VTOD by, for example, applying heat, one or more forces, or both. In some embodiments, the molding apparatus 880 may be at an elevated temperature so that the VTOD substrate is relatively soft and moldable (if it is not already). In some cases, a first force (870-F1) may be applied along a first direction or axis 870, and a second force (872-F2) may be applied along a second direction or axis 872. Simultaneously, an orthogonal force 874-F may be applied as well, which may be generally perpendicular to the plane of the VTOD substrate. These forces form an intermediate VTOD 810′ that begins to change shape. Note that the operation of the shaping device may include one or more actions applied manually by a person. Eventually, the VTOD follows the shaping device to reach the desired curvature (in this case, a multi-curved surface). In some embodiments, upon cooling (if heated), the curved VTOD is formed. FIG. 9 is a perspective view of a non-limiting example of a curved VTOD 910 that may be formed from a substantially planar VTOD 810. For clarity, only the second substrate 912b and the sealing material 913 at the edges are labeled. The curved VTOD 910 may include any of the properties, materials, or layer structures described elsewhere herein.

[0054] The total surface area of ​​the curved VTOD 910 may be greater than the surface area of ​​a substantially planar VTOD 810. In some embodiments, the surface area of ​​the curved VTOD may be at least 5% greater than the original substantially planar VTOD (or corresponding substrate precursor structure) from which it was fabricated, or alternatively, at least 10%, 20%, 30%, 40%, 50%, 60%, 80%, 100%, 125%, 150%, 175%, 200%, 250%, 300%, or 400% greater, or even greater. In some embodiments, these changes in surface area may correspond to the surface area of ​​the transparent electrode layer after bending relative to the surface area of ​​the transparent electrode material before bending. In some cases, the thickness of at least a portion of one or both substrates of the curved VTOD 910 may be less (thinner) than the thickness of the substantially planar VTOD 810.

[0055] Forces can include stretching, pulling, compression, tension, or any force capable of causing at least some increase or other change in surface area. As previously mentioned, heat may optionally be applied so that, for example, the temperature of one or both substrates is within 20°C of the substrate's glass transition temperature (Tg) or above, alternatively, within 10°C of the substrate's Tg or above, alternatively, at least the substrate's Tg, alternatively, at least 10°C above the substrate's Tg. Characterized in another way, the temperature Ts of the substrate may obey the following relationship: Ts≧(Tg−20°C), alternatively, Ts≧(Tg−10°C), alternatively, Ts≧(Tg), or alternatively, Ts≧(Tg+10°C). The temperature should not exceed the point where the substrate becomes so fluid that it can no longer be handled by molding equipment or where an overlying layer no longer adheres. The force may be applied for a period of time that can be a function of temperature and force. In some cases, the applied force and / or temperature may be varied during molding.

[0056] Heat can be applied in a variety of ways. In some embodiments, the substrate(s) may be warmed in an oven and then removed from the molding apparatus. In some cases, the environment or components of the molding apparatus may be heated. Methods of applying heat may include the use of heating elements, IR lamps, flash lamps, hot air supplies, microwaves, or any other suitable heating technology.

[0057] In some embodiments, the molding apparatus may include a physical mold into which the VTOD is compressed or otherwise applied, and then the curved VTOD product is peeled off. In some embodiments, the mold may include a low-adhesion release layer or coating to aid in separating the curved VTOD. In some cases, the molding apparatus may include a carrier that can function as a mold into which the VTOD is compressed, but the curved VTOD remains laminated to the carrier as part of the final product. For example, the VTOD may be laminated onto eyeglass lenses, jet aircraft cockpits, visors, curved windows or mirrors, etc. In some cases, the molding apparatus may utilize the principles of blow molding rather than, or in addition to, a physical mold.

[0058] In some cases, the molding apparatus may employ thermoforming, for example, as described in U.S. Patent Nos. 7,102,602, 7,705,959, and 7,811,482, the contents of which are incorporated herein by reference for all purposes. FIG. 10 is a schematic diagram of a non-limiting example of a molding apparatus, according to some embodiments. In some embodiments, the molding apparatus 1080 may be used to fabricate curved VTODs or VTOD components, such as curved substrate structures. The molding apparatus 1080 may include a heat chamber 1082 capable of raising and lowering the temperature as needed during the fabrication process. Included within the heat chamber 1082 is a pair of opposing platens 1084 that are adaptable to receive pressure 1085 to enable closing and opening of the platens 1084 in a conventional manner. The application of pressure 1085 may be controlled and coordinated with the application of heat in a manner that will be described below. In some cases, the heating element 1087 may be carried by the platen 1084 or even by the molds 1086, 1090. Alternatively or additionally, the substantially planar VTOD 1010 may be heated in a separate chamber and then transferred to the mold in time for forming.

[0059] 10, for clarity, only the substrate 1012b and the sealing material 1013 are labeled, although the substantially planar VTOD 1010 may optionally be similar to those described with respect to the planar VTOD 810 and may include any of a variety of properties, materials, or layer structures as described elsewhere herein. Attached to the upper platen may be a mold half 1086 providing a mold surface 1088. Similarly, attached to the lower platen 1084 may be a second mold half 1090 having a mold surface 1092.

[0060] The substantially planar VTOD 1010 may be inserted between two mold faces 1088 and 1092, each having the desired final shape of each side of the optical device. The faces may fit tightly together, one inside the other, with minimal residual space between them. Alternatively, one mold face may have a slightly different curvature than the other, depending on the end use of the device. The mold faces 1088, 1092 remain relatively rigid and non-deformable throughout the fabrication process. The VTOD 1010 is brought to an elevated temperature by a chamber 1082, and a compressive force 1085 is applied to the VTOD 1010 by a platen 1084, the force being essentially perpendicular to the initial flat VTOD. The temperature and compressive force are generally linked in forming the final product. The temperature and force combination should be great enough to cause the substrate to conform to the mold surfaces 1088, 1092 and to permanently retain the shape of the mold surfaces after the temperature is reduced and the force is removed. In other words, in some embodiments, no other restraining force is required to maintain the curved shape of the optical device. However, the temperature and force generally should not be great enough to force the inner substrate surfaces closer together than the spacers (if present) or the intended cell gap size. It has been found that if the temperature and / or force are too great, the substrates will be forced too close together and will become too soft adjacent to the individual spacers (if used), thereby causing the substrates to dent. Therefore, the temperature / force combination and their application rate must be great enough to impress the initially planar VTOD 1010 with the desired curved shape, but not so great that the cell gap deviates from its intended specifications. At higher processing temperatures, smaller compressive forces may be required. Conversely, at lower processing temperatures, larger compressive forces may be required. It should be understood that the temperature of the process should not exceed the melting temperature of the substrate. In the absence of an additional curing step (such as by radiation), the operating temperature of a curved VTOD produced in this manner is generally below the thermoforming temperature.The compressive force and elevated temperature are applied to the VTOD 1010 for a sufficient time so that after the force is removed and the temperature drops, the VTOD retains the shape blown into it by the mold. Furthermore, the shape generally remains without the application of any other force.

[0061] FIG. 11 is a perspective view of a non-limiting example of a curved VTOD, according to some embodiments. The curved VTOD 1110 can be formed from a molding device acting on the VTOD 1010, as shown in FIG. 10. While only the substrates 1112a, 1112b and sealing material 1113 are labeled in FIG. 11 for clarity, the curved VTOD 1110 can include any of a variety of properties, materials, or layer structure options as described with respect to FIG. 1 and elsewhere herein. While FIG. 10 illustrates a generally single step for forming the curved VTOD, molding may occur in several steps, for example, with multiple molding devices or under multiple conditions (e.g., with respect to temperature, force, etc.) used during molding.

[0062] In some embodiments, rather than forming a substantially planar VTOD, substrate precursor structures may be individually formed, e.g., in a manner similar to any described elsewhere with respect to forming a substantially planar VTOD, or a curved VTOD may be formed through the assembly of pre-curved substrate structures. In some embodiments, such pre-curvature may be only partial (partially curved substrate precursor structures), and the intermediate or partially curved VTOD after assembly from such pre-curved substrate precursor structures may be further formed in a forming apparatus to form a curved VTOD having a desired curvature.

[0063] 12-14 are block diagrams outlining some non-limiting general steps for forming a curved VTOD, according to some embodiments. Referring to FIG. 12, in step 1201, a substantially planar VTOD may be fabricated that does not yet include any electro-optic material (“EOM”). From this step, three general paths are shown: A, B, and C. In path A, the substantially planar VTOD may be filled with an EOM and sealed, as step 1202. In path B, as step 1203, the cell gap of the planar VTOD may instead be filled (fully or partially) with a fugitive material that may be a fluid (gas, liquid, gel) or a malleable solid, and optionally sealed. In step 1204, the planar VTOD may be associated with a molding device that acts on the planar VTOD to cause a change in shape. Step 1204 may be applied after step 1202 for path A, after step 1203 for path B, or after step 1201 for path C. For Path A, a curved VTOD is formed in step 1204. In some embodiments, additional optional actions may be applied to the curved VTOD in step 1207. For example, the curved VTOD may be removed from the mold (if used) and subjected to additional manufacturing steps, which may include, but are not limited to, lamination to a carrier, bonding electrical connections, applying an overcoat, or some other step. In some cases, the curved VTOD after step 1204 may still be laminated to its intended carrier and does not need to be removed. For Path B, after step 1204, a temporary material may be removed in step 1205. The molded VTOD may be filled and sealed with an electro-optic material as step 1206, which may be applied after step 1205 for Path B or after step 1204 for Path C. For Paths B and C, the curved VTOD is formed in step 1206 and may optionally undergo additional actions in step 1207, as described above. Many variations on these primary paths exist.For example, in paths B and C, the molded VTOD may be removed from the mold (if used) before filling with the electro-optic material, rather than being removed as part of step 1207.

[0064] In FIG. 13 , step 1301 involves fabricating or otherwise providing substantially planar substrate precursor structures. As described elsewhere herein, the substrate precursor structures may include, for example, a transparent electrode material, such as a hybrid conductor material, provided on a substantially planar flexible substrate. In step 1302, the substrate precursor structures are provided in association with a molding device that acts on them to change their shape and form pre-curved substrate structures. The pre-curved substrate structures generally retain their new shape and can have the desired curvature in the finished curved VTOD. Each substrate precursor structure may be molded in the same molding device or in different molding devices, either sequentially or simultaneously. In step 1303, the pre-curved substrate structures may be aligned and assembled to form the curved VTOD. In some cases, this may include removing each pre-curved substrate structure from a mold (if used) and transferring it to an assembly station. In step 1304, optional additional actions may be applied to the curved VTOD. For example, the curved VTOD may undergo additional manufacturing steps, which may include, but are not limited to, lamination to a carrier, bonding electrical connections, applying an overcoat, or some other step. In some embodiments, one of the pre-curved substrate structures may be formed directly on the intended carrier, and the curved VTOD is assembled in place.

[0065] In FIG. 14 , step 1401 involves fabricating or otherwise providing substantially planar substrate precursor structures. As described elsewhere herein, the substrate precursor structures may include, for example, a transparent electrode material, such as a hybrid conductor material, provided on a substantially planar flexible substrate. In step 1402, the substrate precursor structures are provided in association with a molding device that acts on them to change their shape and form partially curved substrate precursor structures. The partially curved substrate precursor structures generally retain their new shape but do not yet have the curvature desired for the finished curved VTOD. Each substrate precursor structure may be molded in the same molding device or in different molding devices, either sequentially or simultaneously. In step 1403, the partially curved substrate precursor structures may be aligned and assembled to form a partially curved VTOD that does not yet include any electro-optic material. In some cases, this may include removing each partially curved substrate precursor structure from a mold (if used) and transferring it to an assembly station. At this point, the partially curved VTOD may generally follow the steps and path options as outlined in Figure 12. That is, step 1403 may replace step 1201, and then steps 1202-1207, corresponding to paths A, B, and C, may follow as described with respect to Figure 12.

[0066] Effect of stretching on device performance The authors found that many conventional transparent electrode materials tend to split into isolated sections or islands when the substrate precursor structure is, for example, thermoformed or stretched in a molding device. This is particularly true for brittle metal oxide conductors such as ITO or AZO. For example, FIG. 15A is a schematic top-view diagram of a substrate precursor structure 1511 having a continuous (conventional) transparent electrode material layer 1514, made from, for example, ITO or AZO, before stretching. FIG. 15B shows the same view after stretching along axes 1570 and 1572. The post-stretching substrate structure 1511′ shows areas or islands of transparent conductive material 1514′ separated by substrate 1512′. The substrate structure 1511′ would obviously fail electrically due to discontinuities in the conductive layer. Even thin, continuous optically transparent metal layers, while potentially more ductile than metal oxides, would ultimately result in similar discontinuities because their ductility and stretching capabilities are generally more limited than the substrate itself. Thicker metal layers can be stretched better than thinner metal layers, but thicker metals are not useful because they are not transparent. The failure point due to stretching depends in part on the particular electrode material, but for conventional transparent thin metal or TCO layers, the area change is generally less than 10%, and in some cases less than 5%, 3%, 2%, or even 1%. In some cases, the area change can be caused by uniaxial stretching, or alternatively, by biaxial stretching.

[0067] Coatings of conductive particles such as metal nanowires (optionally with a polymer binder) can provide greater stretchability than metal oxides. However, even metal nanowire coatings can fail with sufficient stretching. Figure 16A is a schematic top-view diagram of a substrate precursor structure 1611 having a transparent electrode layer made from metal nanowires 1614, e.g., silver nanowires, provided on a substrate 1612. The areal density of the nanowires is sufficient, so that conductivity across the surface is achieved by random contact from one nanowire to another. Figure 16B shows a similar diagram after stretching along axes 1670 and 1672. The post-stretching substrate structure 1611' shows that many of the nanowires 1614' deposited on the stretched substrate 1612' have been pulled apart, resulting in less contact between the nanowires. This can increase the resistivity of the electrodes. Such increased resistivity can impose higher energy requirements for driving the device or can result in device shorting. Resistance variations across the electrode can also cause unacceptable non-uniformity in device performance. Sufficient stretching can increase resistance to the point where conductivity may be further lost across portions of the substrate structure. The failure point due to stretching depends in part on the density of the nanowire coating. While dense coatings of nanowires can be stretched significantly and maintain continuity, such dense coatings are not useful because they are not transparent. Even when stretched to a sufficiently low level to be "transparent," they can still impart haze or an undesirable metallic sheen. Conventional transparent coatings of metal nanowires that are acceptable in terms of resistance, haze, transparency, etc., can begin to fail upon stretching with less than a 60% area change, and in some cases less than 50%, 40%, 30%, 20%, 10%, or even 5%. In some cases, the area change can be caused by uniaxial stretching or, alternatively, biaxial stretching. In some cases, uniaxial stretching can cause an unacceptable decrease in conductivity when stretched 1.6 times its original length.In some cases, biaxial stretching can cause unacceptable degradation of electrical conductivity when stretched to 1.4 times the original length. Note that the above discussion regarding Figures 16A and 16B may also apply to CNTs in some cases.

[0068] The authors found that conductive polymer materials generally have much higher stretch resistance than TCOs or metal nanowires, and can maintain better conductivity across the substrate even after significant stretching. However, conductive polymers typically have a higher overall resistance than TCOs or conductive particles (e.g., metal nanowires, carbon nanotubes, etc.) at a particular target transmittance. In some embodiments, conductive polymers may absorb too much light to achieve the desired electrical performance.

[0069] However, it has been discovered that transparent electrodes having hybrid conductor materials, as described elsewhere herein, can surprisingly provide both good electrical and optical performance, even after stretching (forming). Without being bound by any theory, it may be that in some cases, after stretching, the conductive polymer (which may in some cases include an intrinsically conductive polymer) acts as a bridge between discontinuous areas of the auxiliary conductor material (e.g., metal oxide islands, nanowires, etc.) of the hybrid conductor. When acting as a bridge, the conductive polymer need not be the sole transporter of electrons or the sole creator of the electric field; other conductive materials may still actively participate in electron transport and electric field generation, albeit less continuously after stretching.

[0070] As mentioned above, in some embodiments, the substrate structure may intentionally not include a hard coat layer. Most hard coat layers are relatively brittle and may break into islands upon molding or stretching, in a manner similar to that shown with respect to FIG. 15 . The formation of islands or cracks in the hard coat may manifest as haze visible to an observer. However, in addition to protecting the substrate from scratches and the like, a hard coat can, in some cases, protect the substrate from aggressive organic solvents. It has also been found that coating a polyimide alignment layer over a conductive nanoparticle-based transparent electrode (e.g., metal nanowires, carbon nanotubes, etc.) can result in some damage to the substrate in the absence of a hard coat due to attack by the polyimide solvent on the substrate. This can manifest as haze or cause even more severe damage. Greater resistance to polyimide solvents can be achieved by adding a conductive polymer (e.g., mixing or overcoating metal NWs or CNTs with an intrinsically conductive polymer such as PEDOT:PSS) to create a hybrid conductor in the manner described elsewhere. In some cases, the conductive polymer may be hydrophilic and not readily soluble in organic solvents such as those used in polyimide coatings. [Example]

[0071] 17A and 17B are photographs from two different angles of a substrate precursor structure being stretched or thermoformed on a mold to form a curved substrate structure. XYZ axes have been added to these drawings for perspective. The curved substrate structure has a multi-curved structure and is biaxially stretched. Grid lines were drawn to mark various sections of the curved substrate structure for subsequent sheet resistance measurements. Two different substrate structures were formed on this mold in a similar manner. Near the center of the mold, the surface area of ​​the curved substrate structure was approximately 100% (approximately 2 times) higher than that of the original substrate precursor structure.

[0072] The substrate precursor structure of Comparative Example A included a 100 micron thick polycarbonate film onto which a transparent conductive electrode containing silver nanowires was applied using known coating methods. A polyimide alignment layer was provided on top of the transparent conductive electrode. The substrate did not include a hard coat. The substrate precursor structure of Comparative Example A had a resistance of approximately 40 ohms / square and a transmittance of greater than 90% in the range of 400 nm to 730 nm.

[0073] The substrate precursor structure of Example 1 was similar to that of Comparative Example A, but further included a layer of conductive polymer material (PEDOT-based) provided on the layer of silver nanowires to form a transparent hybrid conductor. The conductive polymer layer had a dry thickness on the order of tens of nanometers. A polyimide alignment layer was provided on top of the conductive polymer layer. The substrate precursor structure of Example 1 had a resistivity of approximately 34 ohms / square and a transmittance of greater than 90% in the range of 400 nm to 730 nm.

[0074] Comparative A and Example 1 were then molded to form curved substrate structures, Comparative A' and Example 1', respectively. Molding was achieved by drawing the substrate over a mold head at a temperature of about 133°C and under an air pressure of about 70 PSI. Comparative A' and Example 1' were similar in appearance to the images shown in Figures 17A and 17B.

[0075] FIG. 18 is a map of sheet resistance across a curved substrate structure, with the left half representing data from Comparative Example A' and the right half representing data from Example 1'. FIG. 19 is a histogram showing the distribution of counts across each sample within a particular sheet resistance range. From both FIGS. 18 and 19, it is clear that Example 1' is much less resistive than Comparative Example A'. Comparative Example A' exhibits many regions of sheet resistance higher than about 500 ohms / square, while Example 1' has none. Example 1' includes many grid areas with sheet resistances below 50 ohms / square, while Comparative Example A' has none. Example 1' has an average sheet resistance of 180 ohms / square with a standard deviation of 140 ohms / square, while Comparative Example A' has an average sheet resistance of 1155 ohms / square with a standard deviation of 701 ohms / square. That is, Example 1' is significantly less resistive and has a tighter distribution of resistance values ​​than Comparative Example A'.

[0076] In some embodiments, the average sheet resistance across the transparent electrodes of a curved VTOD can be less than 500 ohms / sq, alternatively less than 300 ohms / sq, less than 250 ohms / sq, less than 200 ohms / sq, less than 150 ohms / sq, less than 100 ohms / sq, less than 75 ohms / sq, or less than 50 ohms / sq. In some embodiments, the standard deviation of the average sheet resistance across the transparent electrodes is less than 250 ohms / sq, alternatively less than 200 ohms / sq, less than 150 ohms / sq, less than 100 ohms / sq, less than 75 ohms / sq, less than 50 ohms / sq, or less than 25 ohms / sq. In some embodiments, at least 95% of the area across the transparent electrodes of the curved VTOD has a sheet resistance of less than 500 ohms / sq, alternatively less than 300 ohms / sq, 250 ohms / sq, 200 ohms / sq, 150 ohms / sq, 100 ohms / sq, 75 ohms / sq, or 50 ohms / sq. In some embodiments, less than 5% of the area across the transparent electrodes of the curved VTOD has a sheet resistance of greater than 1000 ohms / sq, alternatively greater than 750 ohms / sq, alternatively greater than 500 ohms / sq, alternatively greater than 300 ohms / sq.

[0077] In some embodiments, the average sheet resistance across the transparent electrode of the curved VTOD is about the same as the average sheet resistance across the transparent electrode material of the corresponding substrate precursor structure before forming. In some embodiments, the average sheet resistance of the transparent electrode after forming is at most 10 times, alternatively at most 8 times, alternatively at most 6 times, alternatively at most 5 times, alternatively at most 4 times, alternatively at most 3 times, alternatively at most 2 times, alternatively at most 1.5 times, alternatively at most 1.2 times, compared to before forming.

[0078] Although not illustrated in the discussion herein, any of the VTODs may optionally include patterned, individually addressable electrode segments or areas that can be independently activated to provide localized optical effects. In some cases, the VTOD may have 2-50 such segments, alternatively 2-10, or alternatively 2-6.

[0079] Still further embodiments herein include those listed below. 1. A curved variable transmission optical device ("VTOD"), comprising: a first substrate structure including a first transparent electrode provided on a first substrate; a second substrate structure including a second transparent electrode provided on the second substrate; an electro-optical material provided between the substrates, each transparent electrode being interposed between its respective substrate and the electro-optical material; the first and second substrate structures maintain a curved shape such that the VTOD is characterized by at least a first curvature; A curved variable transmission optical device ("VTOD"), wherein at least one transparent electrode comprises a transparent hybrid conductor having a multilayer or gradient composition structure, the transparent hybrid conductor comprising a conductive polymer. 2. The optical device of embodiment 1, wherein the conductive polymer comprises an intrinsically conductive polymer selected from PEDOT, poly(pyrrole), polyaniline, polyphenylene, poly(acetylene), or a combination thereof. 3. The optical device of embodiment 1 or 2, wherein the conductive polymer comprises one or more conductive agents other than PEDOT, poly(pyrrole), polyaniline, polyphenylene, or poly(acetylene). 4. The optical device of any one of embodiments 1 to 3, wherein the transparent hybrid conductor further comprises an auxiliary conductor selected from a transparent conductive oxide, a metal, a metal particle, graphene, a carbon nanotube, or a combination thereof. 5. The optical device of embodiment 4, wherein the metal particles comprise metal nanowires. 6. An optical device as described in embodiment 4 or 5, wherein the conductive polymer and the auxiliary conductor are provided in a common layer, and the weight percentage of the auxiliary conductor in the lower portion adjacent to the substrate is different from the weight percentage in the upper portion adjacent to the electro-optical material. 7. The optical device according to embodiment 4 or 5, wherein the conductive polymer and the auxiliary conductor are provided in different layers. 8. An optical device according to any one of embodiments 1 to 7, wherein at least one transparent electrode corresponds to a first transparent electrode comprising a first hybrid conductor, and the second transparent electrode comprises a second hybrid conductor. 9. The optical device of any one of embodiments 1 to 8, wherein the first transparent electrode is substantially the same as the second transparent electrode in terms of composition and thickness. 10. The optical device of any one of embodiments 1 to 8, wherein the first transparent electrode differs from the second transparent electrode in terms of composition or thickness. 11. The optical device of any one of embodiments 1 to 10, wherein one or both of the first and second substrates comprises polycarbonate. 12. An optical device according to any one of embodiments 1 to 11, wherein the curved shape comprises a multi-curved surface having a first curvature along a first axis and a second curvature along a second axis. 13. An optical device according to embodiment 12, wherein the area of ​​the multi-curved surface is in the range of 2 to 400% larger than the virtual area defined by the projection of the multi-curved surface onto the virtual plane. 14. An optical device according to embodiment 12, wherein the area of ​​the multi-curved surface is in the range of 40 to 200% larger than the virtual area defined by the projection of the multi-curved surface onto the virtual plane. 15. The optical device according to any one of embodiments 12 to 14, wherein the first curvature is different from the second curvature. 16. The optical device according to any one of embodiments 12 to 14, wherein the first curvature is the same as the second curvature. 17. The optical device of any one of embodiments 1 to 16, wherein the electro-optical material comprises a liquid crystal and optionally a dichroic dye. 18. The optical device of any one of embodiments 1 to 17, further comprising an alignment layer disposed between the transparent hybrid conductor and the electro-optic material. 19. The optical device of embodiment 18, wherein the alignment layer comprises polyimide. 20. The optical device of any one of embodiments 1 to 19, wherein the transparent hybrid conductor comprises a layer comprising metal nanowires disposed on the first substrate, and a layer comprising an intrinsically conductive polymer disposed on the metal nanowires. 21. A method of making a curved VTOD, the method comprising: a) providing a substantially planar VTOD in association with a molding device, the substantially planar VTOD comprising: i) a first substrate precursor structure comprising a first transparent electrode material provided on a substantially planar first flexible substrate; ii) a second substrate precursor structure comprising a second transparent electrode material provided on a substantially planar second flexible substrate; iii) providing a cell gap provided between the substrate precursor structures, each transparent electrode being interposed between its respective flexible substrate and the cell gap; b) applying heat, force, or both heat and force to the substantially planar VTOD to permanently change shape of the first and second substrate precursor structures according to a shaping device to form a curved VTOD comprising at least a first curvature; The method, wherein at least one transparent electrode material comprises a transparent hybrid conductor having a multilayer or gradient composition structure, and the transparent hybrid conductor comprises a conductive polymer. 22. The method of embodiment 21, wherein the conductive polymer comprises an intrinsically conductive polymer selected from PEDOT, poly(pyrrole), polyaniline, polyphenylene, poly(acetylene), or a combination thereof. 23. The method of embodiment 21 or 22, wherein the conductive polymer comprises one or more conductive agents other than PEDOT, poly(pyrrole), polyaniline, polyphenylene, or poly(acetylene). 24. The method of any one of embodiments 21-23, wherein the transparent hybrid conductor further comprises an auxiliary conductor selected from a transparent conductive oxide, a metal, a metal particle, graphene, a carbon nanotube, or a combination thereof. 25. The method of embodiment 24, wherein the metal particles comprise metal nanowires. 26. The method of embodiment 24 or 25, wherein the conductive polymer and the auxiliary conductor are provided in a common layer, and the weight percentage of the auxiliary conductor in the lower portion adjacent the substrate is different from the weight percentage in the upper portion adjacent the electro-optical material. 27. The method of embodiment 24 or 25, wherein the conductive polymer and the auxiliary conductor are provided in different layers. 28. The method of any one of embodiments 21-27, wherein at least one transparent electrode material corresponds to a first transparent electrode material comprising a first hybrid conductor, and the second transparent electrode material comprises a second hybrid conductor. 29. The method of any one of embodiments 21-28, wherein the first transparent electrode material is substantially the same as the second transparent electrode material in terms of composition and thickness. 30. The method of any one of embodiments 21-28, wherein the first transparent electrode material differs from the second transparent electrode in terms of composition or thickness. 31. The method of any one of embodiments 21-30, wherein one or both of the first and second flexible substrates comprises polycarbonate. 32. The method of any one of embodiments 21-31, wherein the curved VTOD comprises a multi-surface. 33. The method of any one of embodiments 21-32, wherein the surface area of ​​the curved VTOD is at least 10% higher, or optionally at least 50% higher, than the surface area of ​​the substantially planar VTOD. 34. The method of any one of embodiments 21-33, wherein heat is applied such that the temperature of at least one of the first and second flexible substrates is within 20°C of the Tg of the at least one substrate or equal to or greater than the Tg of the at least one substrate, or optionally within 10°C of the Tg of the at least one substrate or equal to or greater than the Tg of the at least one substrate. 35. The method of any one of embodiments 21-34, further comprising contacting the substantially planar VTOD with a mold. 36. The method of embodiment 35, further comprising removing the curved VTOD from the mold. 37. The method of embodiment 34, further comprising permanently laminating the curved VTOD to a mold, the mold comprising a device carrier. 38. The method of embodiment 37, wherein the device carrier comprises a curved lens, a curved window, a curved sunroof, a curved windshield, a curved visor, or a curved mirror. 39. The method of any one of embodiments 21-38, wherein the average sheet resistance across the hybrid conductor after step (b) is less than 10 times, or optionally less than 5 times, the average sheet resistance across the hybrid conductor before step (b). 40. The method of any one of embodiments 21-39, wherein the substantially planar VTOD further comprises an alignment layer disposed between the transparent hybrid conductor and the cell gap. 41. The method of any one of embodiments 21-40, wherein the substantially planar VTOD further comprises an electro-optic material disposed in the cell gap. 42. The method of any one of embodiments 21-40, further comprising, after step (b), filling the cell gap with an electro-optic material. 43. A method of making a curved substrate structure including a transparent electrode, the method comprising: a) providing a substrate precursor structure in a molding apparatus, the substrate precursor structure comprising a transparent electrode material provided on a substantially planar flexible substrate; b) applying heat, force, or both heat and force to the substrate precursor structure to permanently change shape of the substrate precursor structure in accordance with the shaping device to form a curved substrate structure characterized by at least a first curvature; The method, wherein the transparent electrode material comprises a transparent hybrid conductor having a multilayer or gradient composition structure, and the transparent hybrid conductor comprises a conductive polymer. 44. The method of embodiment 43, wherein the conductive polymer comprises an intrinsically conductive polymer selected from PEDOT, poly(pyrrole), polyaniline, polyphenylene, poly(acetylene), or a combination thereof. 45. The method of embodiment 43 or 44, wherein the conductive polymer comprises one or more conductive agents other than PEDOT, poly(pyrrole), polyaniline, polyphenylene, or poly(acetylene). 46. ​​The method of any one of embodiments 43-45, wherein the transparent hybrid conductor further comprises a transparent auxiliary conductor selected from a transparent conductive oxide, a metal, a metal particle, graphene, a carbon nanotube, or a combination thereof. 47. The method of embodiment 46, wherein the metal particles comprise metal nanowires. 48. The method of embodiment 46 or 47, wherein the conductive polymer and the auxiliary conductor are provided in a common layer, and the weight percentage of the auxiliary conductor in the lower portion adjacent the substrate is different from the weight percentage in the upper portion adjacent the electro-optical material. 49. The method of embodiment 46 or 47, wherein the conductive polymer and the auxiliary conductor are provided in different layers. 50. The method of any one of embodiments 43-49, wherein the flexible substrate comprises polycarbonate. 51. The method of any one of embodiments 43-50, wherein the curved substrate structure comprises multiple curved surfaces. 52. The method of any one of embodiments 43-51, wherein the surface area of ​​the curved substrate structure is at least 10% higher, or optionally at least 50% higher, than the surface area of ​​the substrate precursor structure. 53. The method of any one of embodiments 43-52, wherein heat is applied so that the temperature of the flexible substrate is within 20°C of the Tg of the substrate or above the Tg of the substrate, or optionally within 10°C of the Tg of the substrate or above the Tg of the substrate. 54. The method of any one of embodiments 43-53, further comprising contacting the substrate precursor structure with a mold. 55. The method of any one of embodiments 43-54, wherein the average sheet resistance across the hybrid conductor after step (b) is less than 10 times the average sheet resistance across the hybrid conductor before step (b). 56. The method of any one of embodiments 43-51, wherein the substrate precursor structure further comprises an alignment layer disposed over the transparent electrode material. 57. A curved variable transmission optical device ("VTOD") comprising: a first substrate structure including a first transparent electrode provided on a first substrate; a second substrate structure including a second transparent electrode provided on the second substrate; an electro-optical material provided between the substrates, each transparent electrode being interposed between its respective substrate and the electro-optical material; A curved variable transmission optical device ("VTOD"), wherein at least one of the first and second substrate structures is fabricated by the method of any one of embodiments 43-56. 58. An article of manufacture comprising the VTOD of any one of embodiments 1-20 or 57, or comprising the VTOD made by the method of any one of embodiments 21-42, wherein the article of manufacture comprises a camera filter, eyeglasses, a visor, goggles, a face shield, an AR / VR headset, a near-eye display, a window, a windshield, a sunroof, a head-up display, or an optical device.

[0080] The specific details of the particular embodiments may be combined in any suitable manner without departing from the spirit and scope of the embodiments of the invention, however, other embodiments of the invention may be directed to the particular embodiments in relation to each individual aspect, or to particular combinations of these individual aspects.

[0081] The above description of exemplary embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to be limited to the precise form described, and many modifications and variations are possible in light of the above teaching.

[0082] In the foregoing description, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that certain embodiments may be practiced without some of these details or with additional details.

[0083] While several embodiments have been described, those skilled in the art will recognize that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the invention. Additionally, certain well-known processes and elements have not been described to avoid unnecessarily obscuring the invention. Additionally, the details of any particular embodiment may not always be present in variations of that embodiment or may be added to other embodiments.

[0084] Where a range of values ​​is provided, unless the context expressly dictates otherwise, it is understood that each intervening value between the upper and lower limit of that range is also specifically disclosed, to the tenth of the unit of the lower limit. Each subrange between any stated or intervening value in a stated range and any other stated or intervening value within that stated range is encompassed. The upper and lower limits of these smaller ranges may independently be included or excluded, and each range where either, neither, or both limits are included in the smaller range is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where a stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

[0085] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, a reference to a "method" includes a plurality of such methods; a reference to a "layer" includes one or more layers and equivalents thereof known to those skilled in the art, and so forth. The invention has been described in detail herein for purposes of clarity and understanding. However, it will be understood that certain changes and modifications can be practiced within the scope of the appended claims.

[0086] All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes. None is admitted to be prior art. [Explanation of symbols]

[0087] 10 Curved VTOD 11a First substrate structure 11b Second substrate structure 12a First substrate 12b Second substrate 13 Sealing materials 14a First transparent electrode 14b Second transparent electrode 15 Controller 18 Alignment Layer 20 cell gap 25 Electro-optical materials, liquid crystal guest-host mixtures 26 Incident light 27 Transmitted light 28 Switch 211 Substrate Structure 212 Transparent substrate 214 Transparent Hybrid Conductor 231 Lower part 233 Upper part 311 Substrate Structure 312 Substrate 314 Transparent Hybrid Conductor 331 First (or Lower) Conductive Layer 333 Second (or upper) conductive layer 341 Conductive Polymer Materials 343 Auxiliary Conductor 411 Substrate Structure 412 Substrate 414 Transparent Hybrid Conductor 431 Lower conductive layer 432 Intermediate conductive layer 433 Upper conductive layer 500 Curved VTOD 662 Curved surface 762 Multi-curved surface 810 VTOD 811a First substrate precursor structure 811b Second substrate precursor structure 812a First flexible substrate 812b Second flexible substrate 813 Sealing materials 814a First transparent electrode material 814b Second transparent electrode material 818 Alignment Layer 820 cell gap 825 Electro-optical materials 880 Molding equipment 910 Curved VTOD 912 Second board 913 Sealing materials 1010 Virtually planar VTOD 1012 board 1013 Sealing materials 1080 Molding equipment 1082 Heat Chamber 1084 Lower Platen 1086 Molds and half molds 1087 Heating element 1088 mold surface 1090 mold 1090 Second half mold 1092 mold surface 1110 Curved VTOD 1112 board 1113 Sealing materials 1511 Substrate precursor structure 1514 Transparent electrode material layer 1611 Substrate precursor structure 1612 board 1614 Metal Nanowires

Claims

1. 1. A curved variable transmission optical device (“VTOD”), comprising: a first substrate structure comprising a first transparent electrode provided on a first substrate; a second substrate structure comprising a second transparent electrode provided on the second substrate; an electro-optical material provided between the substrates, each transparent electrode being interposed between its respective substrate and the electro-optical material; the first and second substrate structures maintain a curved shape such that the VTOD is characterized by at least a first curvature; A curved variable transmission optical device ("VTOD"), wherein at least one transparent electrode comprises a transparent hybrid conductor having a multilayer or gradient composition structure, said transparent hybrid conductor comprising a conductive polymer.

2. The optical device of claim 1 , wherein the conductive polymer comprises PEDOT, poly(pyrrole), polyaniline, polyphenylene, poly(acetylene), or a combination thereof.

3. The optical device of claim 1 , wherein the conductive polymer comprises a polymeric material and one or more conductive agents.

4. 10. The optical device of claim 1, wherein the transparent hybrid conductor further comprises an auxiliary conductor selected from a transparent conductive oxide, a metal, a metal particle, a metal nanowire, graphene, a carbon nanotube, or a combination thereof.

5. 5. The optical device of claim 4, wherein the conductive polymer and the auxiliary conductor are provided in a common layer, and the weight percentage of the auxiliary conductor in the portion adjacent to the substrate is different from the weight percentage in the portion adjacent to the electro-optical material.

6. The optical device of claim 4 , wherein the conductive polymer and the auxiliary conductor are provided in different layers.

7. The optical device of claim 1 , wherein the at least one transparent electrode corresponds to the first transparent electrode comprising a first hybrid conductor, and the second transparent electrode comprises a second hybrid conductor.

8. The optical device of claim 1 , wherein the first transparent electrode is substantially the same as the second transparent electrode in terms of composition and thickness.

9. The optical device of claim 1 , wherein the first transparent electrode differs from the second transparent electrode in terms of composition or thickness.

10. The optical device of claim 1 , wherein one or both of the first and second substrates comprises polycarbonate.

11. 10. The optical device of claim 1, wherein the curved shape comprises a multi-curved surface including a first curvature along a first axis and a second curvature along a second axis, the first and second curvatures being different or the same.

12. 12. The optical device of claim 11, wherein the area of ​​the multi-curved surface is in the range of 2 to 400% larger than an imaginary area defined by a projection of the multi-curved surface onto an imaginary plane.

13. The optical device of claim 1 , wherein the electro-optic material comprises a liquid crystal.

14. The optical device of claim 13 , wherein the electro-optic material further comprises a dichroic dye.

15. The optical device of claim 1 , further comprising an alignment layer disposed between the transparent hybrid conductor and the electro-optic material.

16. 10. An article of manufacture comprising the VTOD of claim 1, wherein the article of manufacture comprises a camera filter, eyeglasses, a visor, goggles, a face shield, an AR / VR headset, a near-eye display, a window, a windshield, a sunroof, a head-up display, or an optical instrument.

17. 1. A method of fabricating a curved VTOD, the method comprising: a) providing a substantially planar VTOD associated with a forming apparatus, said substantially planar VTOD comprising: i) a first substrate precursor structure comprising a first transparent electrode material provided on a substantially planar first flexible substrate; ii) a second substrate precursor structure comprising a second transparent electrode material provided on a substantially planar second flexible substrate; iii) a cell gap provided between the substrate precursor structures, each transparent electrode being interposed between its respective flexible substrate and the cell gap; b) applying heat, force, or both heat and force to the substantially planar VTOD to permanently change shape of the first and second substrate precursor structures according to the shaping device to form a curved VTOD comprising at least a first curvature; The method, wherein at least one transparent electrode material comprises a transparent hybrid conductor having a multilayer or gradient composition structure, said transparent hybrid conductor comprising a conductive polymer.

18. 18. The method of claim 17, wherein the conductive polymer comprises PEDOT, poly(pyrrole), polyaniline, polyphenylene, poly(acetylene), or a combination thereof.

19. 20. The method of claim 17, wherein the transparent hybrid conductor further comprises an auxiliary conductor selected from a transparent conductive oxide, a metal, a metal particle, a metal nanowire, graphene, a carbon nanotube, or a combination thereof.

20. 20. The method of claim 19, wherein the conductive polymer and the auxiliary conductor are provided in a common layer, and the weight percentage of the auxiliary conductor in a lower portion adjacent the substrate is different from the weight percentage in an upper portion adjacent the electro-optic material.

21. 20. The method of claim 19, wherein the conductive polymer and the auxiliary conductor are provided in different layers.

22. 20. The method of claim 17, wherein the at least one transparent electrode material corresponds to the first transparent electrode material comprising a first hybrid conductor, and the second transparent electrode material comprises a second hybrid conductor.

23. 18. The method of claim 17, wherein i) the curved VTOD comprises a multi-curved surface; ii) the surface area of ​​the curved VTOD is at least 10% greater than the surface area of ​​the substantially planar VTOD; or iii) both (i) and (ii).

24. 20. The method of claim 17, wherein heat is applied such that the temperature of at least one of the first and second flexible substrates is within 20°C of a Tg of the at least one substrate or equal to or greater than a Tg of the at least one substrate.

25. 20. The method of claim 17, further comprising contacting the substantially planar VTOD with a mold.

26. 20. The method of claim 17, wherein the average sheet resistance across the hybrid conductor after step (b) is less than 10 times the average sheet resistance across the hybrid conductor before step (b).

27. 20. The method of claim 17, further comprising filling the cell gap with an electro-optic material either before or after step (b).

28. 1. A method for fabricating a curved substrate structure with a transparent electrode, the method comprising: a) providing a substrate precursor structure in a molding apparatus, the substrate precursor structure comprising a transparent electrode material provided on a substantially planar flexible substrate; b) applying heat, force, or both heat and force to the substrate precursor structure to permanently change shape of the substrate precursor structure in accordance with the shaping device to form the curved substrate structure characterized by at least a first curvature; The method, wherein the transparent electrode material comprises a transparent hybrid conductor having a multilayer or gradient composition structure, and the transparent hybrid conductor comprises a conductive polymer.

29. 29. The method of claim 28, wherein i) the conductive polymer comprises PEDOT, poly(pyrrole), polyaniline, polyphenylene, poly(acetylene), or a combination thereof; and ii) the hybrid conductor further comprises an auxiliary conductor selected from a transparent conductive oxide, a metal, a metal particle, a metal nanowire, graphene, a carbon nanotube, or a combination thereof.

30. 29. The method of claim 28, wherein i) the surface area of ​​the curved substrate structure is at least 10% higher than the surface area of ​​the substrate precursor structure, ii) the average sheet resistance across the hybrid conductor after step (b) is less than 10 times the average sheet resistance across the hybrid conductor before step (b), or iii) both (i) and (ii).

31. 1. A curved variable transmission optical device (“VTOD”), comprising: a first substrate structure comprising a first transparent electrode provided on a first substrate; a second substrate structure comprising a second transparent electrode provided on the second substrate; an electro-optical material provided between the substrates, each transparent electrode being interposed between its respective substrate and the electro-optical material; 30. A curved variable transmission optical device ("VTOD"), wherein at least one of the first and second substrate structures is fabricated by the method of claim 28.

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