High refractive index birefringent organic solid crystals and methods of making the same

Abstract

This application relates to high refractive index birefringent organic solid crystals and methods of making the same. An optical film is disclosed that includes an organic solid crystal film formed from a continuous organic solid crystal having a first dimension of no less than 100 microns and a second dimension different from the first dimension of no less than 1 centimeter. Methods for making the organic solid crystal film are also described.

Description

[0001] This application is a divisional application of the application filed on July 28, 2021, with application number 202110859837.1 and invention title "High Refractive Index Birefringent Organic Solid Crystal and Manufacturing Method Thereof".

[0002] Related applications

[0003] This application claims the benefit and priority of U.S. Provisional Patent Application Serial No. 63 / 057,764, filed July 28, 2020, and U.S. Non-Provisional Patent Application Serial No. 17 / 369,861, filed July 7, 2021, both of which are incorporated herein by reference in their entirety. Technical Field

[0004] This disclosure relates generally to optical crystals, and more specifically to high-refractive-index optical crystals and methods for their manufacture. background

[0005] There is a high demand for visually appealing, lightweight, compact, and energy-efficient consumer electronics devices. Therefore, there is a desire to design optical elements or optics for use in these devices that are adaptive, optically efficient, lightweight, compact, and broadband.

[0006] Techniques for fabricating optical devices with enhanced optical performance and physical properties have become an attractive subject of research and development. Liquid crystals (“LCs”) have been used to fabricate polarization-selective optical elements. The optical properties of polarization-selective optical elements can depend on the refractive index and / or birefringence of the LC. Currently available LCs can be formulated to achieve a large refractive index of approximately 1.97 and a large birefringence of approximately 0.3. Optical elements based on materials with high refractive indices are highly desirable for reducing size and weight while enhancing optical properties. Overview

[0007] There is a demand for materials with high refractive indices. Furthermore, materials with both high refractive indices and high birefringence offer additional benefits. The methods described herein allow for the fabrication of organic solid crystals with high refractive indices. In some configurations, the organic solid crystals fabricated by the methods described herein are large enough to form optical elements or provide continuous cladding layers on optical elements, thereby allowing for improved performance of the optical elements.

[0008] For example, materials with a refractive index higher than 1.9 are desirable for fabricating waveguide combiners that can support large fields of view. Furthermore, materials with low density are desirable when waveguide combiners are included in head-mounted displays. Organic solid-state crystals possess both high refractive index and low density, enabling the realization of waveguide combiners with large fields of view and low density. In addition, high-refractive-index birefringent materials can be used in a variety of other optical components, such as Fresnel lenses, superlenses, and polarization-selective gratings. By carefully tuning the crystal growth path, organic solid-state crystals can be grown on flat or curved substrates with precisely controlled refractive index orientation. This paper describes such organic crystal materials and the process for growing large-size solid-state crystals with high refractive index and birefringence.

[0009] According to some embodiments, the optical film includes an organic solid crystal film formed of continuous organic solid crystals, the organic solid crystal film having a first dimension of not less than 100 micrometers and a second dimension of not less than 1 centimeter, which is different from the first dimension.

[0010] According to some implementation schemes, the second dimension is not less than three centimeters.

[0011] According to some embodiments, the organic solid crystal film is curved or flat.

[0012] According to some embodiments, the refractive index of the optical film is at least 1.6.

[0013] According to some embodiments, the refractive index of the optical film, measured in a direction perpendicular to or parallel to the surface defined by the organic solid crystal film, is at least 1.6, and the optical anisotropy of the organic solid crystal film is at least 0.03.

[0014] According to some implementation schemes, the optical anisotropy of the optical film is at least 0.1.

[0015] According to some implementation schemes, the organic solid crystal film includes monocrystalline or polycrystalline forms.

[0016] According to some embodiments, the organic solid crystal film comprises one or more organic crystals selected from the group consisting of: naphthalene, anthracene, tetraphenylene, pentaphenylene, pyrene, polyene, fluoranthene, benzophenone, benzochromene, benzoyl, benzimazole, benzene, hexachlorobenzene, nitropyridine-N-oxide, phenyl-1,4-dicarboxylic acid, diphenylacetylene, N-(4-nitrophenyl)-(s)-proline, 4,5-dicyanimazole, benzodithiophene, cyanopyridine, thienothiophene, stilbene, azobenzene and its derivatives.

[0017] According to some embodiments, the organic solid crystal film comprises one or more ring structures, the ring structures containing saturated cyclic groups selected from the group consisting of cyclohexane, cyclopentane, tetrahydropyran, piperidine, tetrahydrofuran, pyrrolidine, tetrahydrothiophene and their derivatives, and unsaturated aromatic groups selected from the group consisting of benzene, naphthalene, anthracene, thiophene, biphenyl, diphenylacetylene, benzimidazole, diphenylacetylene, cyanopyridine, thiophene-thiophene, dibenzothiophene, carbazole, silfluorene and their derivatives.

[0018] According to some implementations, the one or more ring structures are coupled to one or more of the following: C1-C 10 Alkyl, alkoxy, alkenyl groups, -CN, -NCS, -SCN, -SF5, -Br, -Cl, -F, -OCF3, -CF3, and monofluorinated or polyfluorinated C1-C 10 Alkyl or alkoxy.

[0019] According to some embodiments, the organic solid crystalline film comprises one or more crystalline polymers having a precursor with an aromatic hydrocarbon or heteroaromatic hydrocarbon group and its derivatives, wherein the one or more crystalline polymers are selected from the group consisting of: polyethylene naphthalate, poly(vinylphenyl sulfide), poly(α-methylstyrene), polythiophene, polythiophene, poly(n-vinylphthalimide), poly(p-xylene), polysulfides, polysulfones, poly(bromophenyl), poly(vinylnaphthalene), and liquid crystal polymers having a precursor.

[0020] According to some embodiments, the organic solid crystal film is a combination of the following: an amorphous polymer having aliphatic, heteroaliphatic, aromatic, or heteroaromatic groups; fatty acids, lipids, or plasticizers; and surfactants, said surfactants comprising molecules having monofluorinated or polyfluorinated alkyl or alkoxy groups.

[0021] According to some embodiments, the organic solid crystal film comprises one or more organic crystals, wherein the organic crystals are selected from the group consisting of organic solid crystal molecules:

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] R, R1, and R2 are independently selected from the group consisting of: CH3, H, OH, methoxy (OMe), ethoxy (OEt), isopropoxide (OiPr), F, Cl, Br, I, Ph, NO2, SO3, SO2Me, isopropyl (iPr), propyl (Pr), tert-butyl (t-Bu), sec-butyl (sec-Bu), ethyl (Et), acetyl, SH, S-methyl (SMe), carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, N-dimethyl (NMe2), N-methyl (NMeH), and C2H2.

[0030] According to some implementations, the optical film is used to manufacture waveguide combiners, diffractive lenses, or polarization selective gratings.

[0031] According to some embodiments, a method for manufacturing an optical film includes depositing evaporated organic crystal molecules from a source material onto a substrate having a controlled nucleation surface using physical vapor transport; and recrystallizing the evaporated organic crystal molecules on the controlled nucleation surface to form an optical film comprising a continuous organic solid crystal having a first dimension of not less than 100 mm and a second dimension of not less than 1 cm, which is different from the first dimension.

[0032] According to some embodiments, the controlled nucleation surface includes one or more of the following: SiO2, fused silica, quartz, organosilicon, siloxane, silicon, SiC, sapphire, and polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups.

[0033] According to some embodiments, the controlled nucleation surface includes a non-polymer-based coating layer selected from silyl fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, heteroaromatic groups, small organic molecule-based crystals, and any of the following:

[0034]

[0035] R3 is independently selected from the group consisting of: CH3, H, OH, methoxy (OMe), ethoxy (OEt), isopropoxide (OiPr), F, Cl, Br, I, Ph, NO2, SO3, SO2Me, isopropyl (iPr), propyl (Pr), tert-butyl (t-Bu), sec-butyl (sec-Bu), ethyl (Et), acetyl, SH, S-methyl (SMe), carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, N-dimethyl (NMe2), N-methyl (NMeH), and C2H2.

[0036] According to some embodiments, a method for manufacturing an optical film includes obtaining an ampoule having one or more nucleation portions and crystal growth portions coupled to the one or more nucleation portions. The ampoule is filled with an organic solid crystal source material. The method further includes placing the ampoule within a first space of a chamber, thereby heating the organic solid crystal source material to a molten state. The first space has a first temperature, and the chamber also has a second space having a second temperature, the first space and the second space being separated by a gate. The method further includes transferring the ampoule from the first space of the chamber to the second space of the chamber, thereby recrystallizing the organic solid crystal source material to form a continuous organic solid crystal film having a first dimension of not less than 100 micrometers and a second dimension different from the first dimension of not less than 1 centimeter.

[0037] According to some embodiments, the ampoule further includes: a base frame defining the one or more nucleation portions and the crystal growth portion, the base frame including: a double-wall structure having a first wall and a second wall, the double walls at least partially surrounding the respective nucleation regions of the one or more nucleation portions and the crystal growth portion; and a cushioning material placed between the first wall and the second wall.

[0038] According to some implementation schemes, the ampoule-like material includes a controlled nucleation surface in contact with the organic solid crystal source material.

[0039] According to some embodiments, a method for manufacturing an optical film includes coating a solution of organic crystal molecules and a solvent onto a modified surface of a substrate, and changing the temperature of the solution of organic crystal molecules and solvent deposited on the modified surface of the substrate by regional annealing, thereby causing the organic crystal molecules to crystallize to form a continuous organic solid crystal film having a first dimension of not less than 100 micrometers and a second dimension of not less than 1 centimeter, which is different from the first dimension. Brief description of the attached diagram

[0040] Figure 1A A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0041] Figure 1B A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0042] Figure 1C The diagram illustrates the orientation of anisotropic refractive indices on flat and curved substrates according to some embodiments.

[0043] Figure 1D The dimensions of a solid crystal according to some embodiments are schematically illustrated.

[0044] Figure 2A A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0045] Figure 2B A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0046] Figure 2C A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0047] Figure 2D A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0048] Figure 3A A top view of an optical device according to some embodiments is schematically illustrated.

[0049] Figure 3B A top view of an optical device according to some embodiments is schematically illustrated.

[0050] Figure 4A A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0051] Figure 4B A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0052] Figure 4C A cross-sectional view of an optical device according to some embodiments is schematically illustrated.

[0053] Figure 5A A cross-sectional view of an optical waveguide having in-coupling and out-coupling elements is schematically illustrated according to some embodiments.

[0054] Figure 5B A cross-sectional view of an optical waveguide having an input coupling element and an output coupling element according to some embodiments is schematically illustrated.

[0055] Figure 6A A schematic diagram illustrates a three-dimensional (“3D”) view of the spatially varying orientation of the axes of crystal molecules in a solid crystalline film according to some embodiments.

[0056] Figure 6B A schematic 3D diagram illustrating the spatially varying orientation of crystal molecules in a solid crystalline film according to some embodiments is shown.

[0057] Figure 6CA schematic 3D diagram illustrating the spatially varying orientation of crystal molecules in a solid crystalline film according to some embodiments is shown.

[0058] Figure 7A A schematic diagram of a transmissive Pancharatnam Berry phase (“PBP”) optics according to some embodiments is shown.

[0059] Figure 7B The schematic diagram illustrates, according to some implementation schemes, when Figure 7A The diagram shows a cross-sectional view of a portion of the orientation of the crystal molecules' axes when the PBP optics are used as a PBP grating.

[0060] Figure 7C The illustration schematically depicts some implementation schemes. Figure 7B The diagram shows the positive and negative states of the PBP grating.

[0061] Figure 7D The illustration schematically depicts some implementation schemes. Figure 7B The diagram shows the negative state of the PBP grating.

[0062] Figure 8A The schematic diagram illustrates, according to some implementation schemes, when Figure 7A The diagram shows a cross-sectional view of the orientation of the crystal molecules' axes when the PBP optics are used as a PBP lens.

[0063] Figure 8B The diagram illustrates the implementation schemes in... Figure 8A The cross-section shown is a portion of the orientation of crystal molecules taken along the x-axis in the PBP lens.

[0064] Figure 8C The illustration schematically depicts some implementation schemes. Figure 8A The diagram shows the focusing state of the PBP lens.

[0065] Figure 8D The illustration schematically depicts some implementation schemes. Figure 8A The diagram shows the defocus state of the PBP lens.

[0066] Figure 9A A schematic diagram of a reflective PBP optics according to some embodiments is shown.

[0067] Figure 9B The schematic diagram illustrates, according to some implementation schemes, when Figure 9A The diagram shows a 3D image of the spatially varying orientation of crystal molecules when the PBP optics are used as a reflective polarizer holographic (“PVH”) grating.

[0068] Figure 9C The schematic diagram illustrates, according to some implementation schemes, when Figure 9A A cross-sectional view showing the orientation of the crystal molecules' axes when the PBP optics are used as a reflective PVH grating.

[0069] Figure 10A A diagram of a near-eye display (“NED”) according to some implementation schemes is illustrated schematically.

[0070] Figure 10B The illustration schematically depicts some implementation schemes. Figure 10A A top-view cross-sectional view of a portion of the NED shown.

[0071] Figure 11A This is a flowchart illustrating a method for manufacturing optical devices according to some embodiments.

[0072] Figure 11B This is a flowchart illustrating a method for manufacturing optical devices according to some embodiments.

[0073] Figure 11C This is a flowchart illustrating a method for manufacturing optical devices according to some embodiments.

[0074] Figure 11D This is a flowchart illustrating a method for manufacturing optical devices according to some embodiments.

[0075] Figures 12A-12C The diagram schematically illustrates a process for manufacturing optical devices including solid-state crystals according to some embodiments.

[0076] Figures 13A-13D The diagram schematically illustrates a process for manufacturing optical devices including solid-state crystals according to some embodiments.

[0077] Figure 14 A system for manufacturing optical devices including solid crystals, according to some embodiments, is schematically illustrated.

[0078] Figure 15 The illustration shows a method for manufacturing organic crystals using physical vapor transport according to some implementation schemes.

[0079] Figure 16 The illustration shows a method for manufacturing organic crystals using melt recrystallization according to some implementation schemes.

[0080] Figure 17 The illustration shows a method for manufacturing organic crystals using solvent coating and zone annealing according to some embodiments.

[0081] Detailed Explanation

[0082] Embodiments consistent with this disclosure will be described with reference to the accompanying drawings, which are merely illustrative examples and not intended to limit the scope. Where possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts, and their detailed descriptions may be omitted.

[0083] Furthermore, the disclosed embodiments and features of the disclosed embodiments can be combined. The described embodiments are some, but not all, embodiments. Based on the disclosed embodiments, those skilled in the art can derive other embodiments consistent with this disclosure. For example, modifications, adaptations, substitutions, additions, or other changes can be made based on the disclosed embodiments. Such changes to the disclosed embodiments are still within the scope. Therefore, this disclosure is not limited to the disclosed embodiments. Rather, the scope is defined by the appended claims.

[0084] As used herein, the terms “coupled,” “coupled,” “coupling,” or similar terms may include optical coupling, mechanical coupling, electrical coupling, electromagnetic coupling, or combinations thereof. “Optical coupling” between two optical devices refers to a configuration in which the two optical devices are arranged in optical series, and the light output from one optical device can be received directly or indirectly by the other optical device. Optical series refers to the optical positioning of more than one optical device in an optical path such that the light output from one optical device can be transmitted, reflected, diffracted, converted, modified, or otherwise processed or manipulated by one or more other optical devices. In some embodiments, the order in which more than one optical device is arranged may or may not affect the total output of the more than one optical device. Coupling can be direct coupling or indirect coupling (e.g., coupling via an intermediate element).

[0085] The phrase "at least one of A or B" can include all combinations of A and B, such as A only, B only, or A and B. Similarly, the phrase "at least one of A, B, or C" can include all combinations of A, B, and C, such as A only, B only, C only, A and B, A and C, B and C, or A and B and C. The phrase "A and / or B" has a similar meaning to the phrase "at least one of A or B". For example, the phrase "A and / or B" can include all combinations of A and B, such as A only, B only, or A and B. Likewise, the phrase "A, B, and / or C" has a similar meaning to the phrase "at least one of A, B, or C". For example, the phrase "A, B, and / or C" can include all combinations of A, B, and C, such as A only, B only, C only, A and B, A and C, B and C, or A and B and C.

[0086] When a first element is described as being "attached," "provided," "formed," "attached," "installed," "fixed," "connected," "joined," "recorded," or "set" onto a second element, or is "attached," "provided," "formed," "attached," "installed," "fixed," "connected," "joined," "recorded," or "set" on a second element, or is "attached," "provided," "formed," "attached," "installed," "fixed," "connected," "joined," "recorded," or "set" at or at least partially "attached," "provided," "formed," "attached," "installed," "fixed," "connected," "joined," "recorded," or "set" in a second element, the first element may be "attached," "provided," "formed," "attached," "installed," "fixed," "connected," "joined," "recorded," or "set" to the second element by any suitable mechanical or non-mechanical means. The first element is "attached," "provided," "formed," "attached," "mounted," "fixed," "connected," "joined," "engraved," or "set" on the second element, or is at least partially "attached," "provided," "formed," "attached," "mounted," "fixed," "connected," "joined," "engraved," or "set" in the second element, by mechanical or non-mechanical means such as deposition, coating, etching, bonding, gluing, threading, press-fit, snap-fit, clamping, etc. Furthermore, the first element may be in direct contact with the second element, or an intermediate element may exist between the first and second elements. The first element may be positioned on any suitable side of the second element, such as the left, right, front, rear, top, or bottom.

[0087] When a first element is shown or described as being set or arranged "on" a second element, the term "on" is used only to indicate an exemplary relative orientation between the first and second elements. This description may be based on a reference coordinate system shown in the figure, or it may be based on the current view or exemplary configuration shown in the figure. For example, when describing a view shown in the figure, the first element may be described as being set "on" the second element. It should be understood that the term "on" does not necessarily mean that the first element is above the second element in a vertical direction of gravity. For example, when the components of the first and second elements are rotated 180 degrees, the first element may be "below" the second element (or the second element may be "on" the first element). Therefore, it should be understood that when the figures show the first element "on" the second element, this configuration is merely an illustrative example. The first element may be set or arranged relative to the second element in any suitable orientation (e.g., on or above the second element, below or under the second element, to the left of the second element, to the right of the second element, behind the second element, in front of the second element, etc.).

[0088] The wavelength ranges or bands mentioned in this disclosure are for illustrative purposes only. The disclosed optical devices, systems, elements, components, and methods can be applied to the visible wavelength range as well as other wavelength ranges, such as the ultraviolet (“UV”) wavelength range, the infrared (“IR”) wavelength range, or combinations thereof.

[0089] Optical devices, such as lenses, waveplates, gratings, and waveguides, have been widely used in optical systems. For example, such optical devices have been implemented in near-eye displays (“NEDs”) for augmented reality (“AR”) applications, virtual reality (“VR”) applications, and / or mixed reality (“MR”) applications. For instance, optical waveguides have been used in NEDs to cover the virtual and real worlds. When a waveguide is used as a combiner to cover virtual and real-world images, for example, in AR applications, it can also be referred to as a waveguide combiner. A waveguide display system may include a light source component configured to emit image light, and a waveguide configured to guide the image light to the user's eye. Image light from the light source component (e.g., a virtual image projector) can be coupled into the waveguide and relayed to the eye via total internal reflection (“TIR”) within the waveguide. The image light emitted from the light source component may include a variety of different colors (e.g., red, green, and blue). In some implementations, multiple waveguides sharing a spectral band can be used to efficiently deliver image light of different colors to the eye, which can increase the number and weight of optical elements (and thus the size and weight of the waveguide display system). Furthermore, the field of view (“FOV”) of the virtual world can depend on the refractive index of the waveguide material. The FOV provided by the waveguide can increase with increasing refractive index of the waveguide material.

[0090] Furthermore, polarization-selective optics have been used in NEDs as input coupling elements (e.g., gratings) in waveguide combiners, adjustment elements in zoom / multifocal blocks, and / or eye-tracking components in eye-tracking systems. Liquid crystals (“LCs”) have been used to fabricate polarization-selective optics. The optical properties of polarization-selective optics can depend on the refractive index and / or birefringence of the LC. For example, the angle and diffraction bandwidth of a polarization-selective LC grating can increase with increasing birefringence of the LC. Currently available LCs can be configured to achieve refractive indices up to about 1.97 and birefringences up to about 0.3. Optical waveguides and polarization-selective optics based on materials with high refractive indices and large birefringences are highly desirable for reducing the size and weight of NEDs, enhancing optical properties, and realizing future smart NEDs.

[0091] This disclosure provides an optical device comprising a solid crystal (or solid crystal material) in the form of a solid crystal film or layer. The solid crystal material may include organic materials, inorganic materials, or combinations thereof. For example, a solid crystal may include organic and crystalline materials, organic and amorphous materials, organic and amorphous materials, organic and semi-crystalline and semi-amorphous materials, inorganic and crystalline materials, inorganic and amorphous materials, inorganic and semi-crystalline and semi-amorphous materials, organic and semi-crystalline and semi-amorphous materials, inorganic and semi-crystalline and semi-amorphous materials, or combinations thereof. For the purposes of discussion, solid organic crystal materials may be used as examples of solid crystal materials. For ease of discussion, solid crystal molecules contained in a solid crystal material may be referred to as organic molecules or crystal molecules. It should be understood that the technical solutions disclosed herein are not limited to organic crystal materials.

[0092] As used herein, the “axis” of a crystal (or solid crystal) may refer to the axis of the solid crystal along which it has the highest or greatest refractive index. The “axis” of crystal molecules contained in a solid crystal may refer to the axis of crystal molecules along which they may have the highest or greatest refractive index. The axis of a crystal can be a clustering effect of the axes of crystal molecules contained in the crystal. The orientation of the axes of crystal molecules contained in a solid crystal (and therefore the orientation of the axis of the solid crystal) can be configured such that the solid crystal can provide at least one predetermined optical function for an optical device comprising the solid crystal. The orientation of the axis of a solid crystal can be a clustering effect of the orientation of the axes of crystal molecules in the solid crystal. The above definitions of the axes of a solid crystal and the axes of crystal molecules are for ease of discussion. The orientations associated with solid crystals and crystal molecules are not limited to those defined by the refractive index along which it is the highest. Other suitable axes (e.g., the axis along which the refractive index is minimum, or the axis perpendicular to which the refractive index is maximum) can be used as configurable objects for discussing the orientation of solid crystals and the orientation of crystal molecules, or for discussing alignment patterns associated with solid crystals or crystal molecules.

[0093] In some embodiments, the orientation of the axes of a solid crystal can be configured by aligning crystal molecules with a predetermined alignment pattern (e.g., aligning the orientation of the axes of the crystal molecules). In some embodiments, the predetermined alignment pattern may refer to a non-natural alignment pattern of the crystal molecules in the solid crystal. For example, the predetermined alignment pattern may be at least partially configured on a substrate on which the crystal molecules are disposed, or may be configured within the solid crystal by a special mechanism (e.g., etching), or may be configured in a separate material disposed on the substrate. The predetermined alignment pattern of the crystal molecules may be specifically designed, configured, or introduced for the purpose of achieving at least one predetermined optical function of the optical element. The predetermined alignment pattern may be a one-dimensional pattern (e.g., crystal molecules may be aligned in the same single direction), a two-dimensional pattern (e.g., crystal molecules may be aligned in a predetermined direction in a two-dimensional plane), or a three-dimensional pattern (e.g., crystal molecules may be aligned in three-dimensional directions).

[0094] In some embodiments, a predetermined alignment pattern of the crystal molecules of a solid crystal can be configured, set, or defined at least partially by an alignment structure. In some embodiments, the alignment structure can be an alignment film or layer formed, etched, set, or otherwise provided at the surface of a substrate, where the crystal molecules of the solid crystal are disposed. In some embodiments, the alignment structure can be formed of a separate material and disposed at the surface of the substrate. In some embodiments, the alignment structure can be formed directly (e.g., directly etched) at the surface of the substrate (e.g., on the surface of the substrate or at least partially in the surface of the substrate). In some embodiments, the alignment structure can be formed directly within the solid crystal (e.g., a solid crystal layer) via a special mechanism. The alignment structure can be a structural property within the solid crystal. For example, the alignment pattern can be formed during a solid crystal crystallization process in the presence of a magnetic or electric field, which can be configured to influence the alignment of the growing solid crystal. In some embodiments, the alignment structure can be integrally formed at the surface of the solid crystal during the crystallization process.

[0095] In some embodiments, the optical device may include an alignment structure configured to at least partially align crystal molecules with a predetermined alignment pattern. The alignment structure may include an alignment structure pattern or define an alignment structure pattern. In some embodiments, the alignment structure pattern may be substantially identical to the predetermined alignment pattern of the crystal molecules. For example, different layers of crystal molecules contained in a solid crystal may be disposed on the alignment structure. A first or more crystal molecule in contact with the alignment structure may be aligned by the alignment structure with the alignment structure pattern. In some embodiments, a second or more crystal molecule stacked on the first or more crystal molecule in the solid crystal may be aligned with the same pattern as the corresponding first or more crystal molecule. In such a configuration, the crystal molecules in the solid crystal may be substantially aligned with the alignment structure pattern, and the alignment structure pattern may be substantially identical to the predetermined alignment pattern of the crystal molecules.

[0096] In some embodiments, a first or more crystal molecules in contact with the alignment structure may be aligned by the alignment structure in an alignment structure pattern. A second or more crystal molecules disposed on (e.g., stacked on) the first or more crystal molecules may not be aligned in the same pattern as the corresponding first or more crystal molecules (e.g., the second or more crystal molecules may be aligned in a pattern different from the alignment structure pattern). Instead, the second or more crystal molecules may be rotated relative to the corresponding first or more crystal molecules by one or more predetermined rotation angles based on the alignment structure pattern (e.g., the second or more crystal molecules may include twists introduced by chiral dopants added to the solid crystal). The one or more predetermined rotation angles may be at least one of in-plane or out-of-plane rotation angles. The predetermined alignment pattern of the crystal molecules may be the result of a combination of the alignment structure pattern aligning the first or more crystal molecules and the twisted (or rotated) alignment pattern associated with the second or more crystal molecules stacked on the first or more crystal molecules. In such a configuration, the alignment structure pattern of the alignment structure may differ from the predetermined alignment pattern of the crystal molecules. The alignment structure can align crystal molecules at least partially with a predetermined alignment pattern.

[0097] For example, an alignment structure can align crystal molecules (e.g., a first set of more than one molecule) in contact with the alignment structure according to the alignment structure pattern. Remaining crystal molecules (e.g., a second set of more than one) contained in the solid crystal and disposed (e.g., stacked on) the first set of more than one crystal molecules can be aligned relative to their corresponding adjacent first set of more than one crystal molecules already aligned by the alignment structure. In some embodiments, the remaining crystal molecules can follow the same alignment as the first set of more than one crystal molecules. For example, the orientation of the axes of the remaining crystal molecules can follow the orientation of the axes of the corresponding first set of more than one crystal molecules. In some embodiments, at least a portion of the remaining crystal molecules can have an orientation of axes rotated by one or more predetermined rotation angles relative to the orientation of the axes of the corresponding first set of more than one crystal molecules.

[0098] In some embodiments, an alignment structure can refer to a structure (such as a layer, film, or physical feature) configured to define or set the orientation of the axes of crystal molecules (e.g., the growth direction of a solid crystal material grown on the alignment structure). In some embodiments, the alignment structure can be thin, such as a few molecules thick. The layer, film, or physical feature of the alignment structure can interact with the molecules of the solid crystal material to be grown (e.g., solid crystal molecules) via mechanical, dipole-dipole, magnetic, or any other suitable mechanism. For example, the alignment structure can be similar to those structures already used in LC devices (e.g., LC displays) for aligning the orientation of nematic LC molecules.

[0099] In some embodiments, crystal molecules can be substantially uniformly oriented in the alignment structure. That is, the orientation of the axes of the crystal molecules can be substantially uniformly oriented, resulting in a spatially invariant (e.g., constant) orientation of the axes of the solid crystal. In some embodiments, crystal molecules can be non-uniformly oriented in the alignment structure. For example, the orientation of the axes of the crystal molecules can vary in the intrinsic space of the solid crystal, resulting in a spatially varying orientation of the axes of the solid crystal. Optical devices can exhibit different optical functions depending on the different orientations of the axes of the solid crystal, which can be configured by different predetermined alignment patterns of the crystal molecules. For example, optical devices can be used as waveguides, gratings, prisms, lenses, axonopy, optical rotators, waveplates or phase retarders, lens arrays, prism arrays, etc., depending on the predetermined alignment pattern of the crystal molecules.

[0100] Solid crystals can be in the form of layers, films, plates, or stacks of layers, films, or plates. Solid crystals can have high refractive indices. As a result, solid crystals can be manufactured to be thin and lightweight. For example, solid crystals can have a thickness of about 500 nanometers (“nm”) to about 5 micrometers (“μm”). Therefore, optical devices incorporating solid crystals can be manufactured to be thin, lightweight, and compact. Furthermore, the techniques disclosed in this disclosure enable the fabrication of solid crystals with large dimensions. For example, by forming (e.g., growing) a solid crystal using an alignment structure, the solid crystal can be manufactured to have a thickness of 100 micrometers or larger (e.g., about 300-500 micrometers) and one or more lateral dimensions of 10 mm or larger (e.g., about 10 mm-100 mm or larger, about 20 mm-100 mm or larger, about 30 mm-100 mm or larger). Large-size solid crystals can broaden the applications of optical devices in a wide variety of technical fields.

[0101] Figure 1A The diagram schematically illustrates an xz cross-sectional view of an optical element or device 100 according to some embodiments. For example... Figure 1A As shown, the optical device 100 may include a solid crystal 115 in the form of a film (layer or plate) (e.g., also referred to as a solid organic crystal film 115). Although the body of the solid crystal 115 is shown as planar for illustrative purposes, the body of the solid crystal 115 may have a curved shape. In this disclosure, for the purposes of discussion, the solid crystal may also be referred to as a solid crystal film (or solid crystal layer). The solid crystal 115 may include a solid crystal material having more than one crystal molecule.

[0102] In some embodiments, the optical device 100 may further include an alignment structure 110 configured to at least partially define or define the orientation of the axis of the solid crystal 115 or for aligning a predetermined alignment pattern of crystal molecules contained in the solid crystal 115. For the purposes of discussion, the axis of the solid crystal 115 may refer to the axis along which the solid crystal 115 may have the highest or greatest refractive index. The axis of the crystal molecules in the solid crystal 115 may refer to the axis along which the crystal molecules may have the highest or greatest refractive index. The orientation of the axis of the solid crystal 115 may be a clustering effect of the orientation of the axes of the crystal molecules contained in the solid crystal 115. The solid crystal 115 may be disposed on the alignment structure 110. In some embodiments, the solid crystal 115 may be grown on the alignment structure 110. In some embodiments, the alignment structure 110 may be omitted. For example, in the presence of a ferroelectric or ferromagnetic material and a ferroelectric or ferromagnetic field, a predetermined alignment pattern may be introduced into the solid crystal 115 by crystallization.

[0103] In some embodiments, the optical device 100 may further include a substrate 105 configured to provide support and / or protection to a plurality of layers, films, and / or structures disposed on (e.g., disposed on) the substrate 105. An alignment structure 110 may be disposed on the substrate. In some embodiments, the alignment structure 110 may be an integral part of the substrate 105. For example, the alignment structure 110 may be etched onto the surface of the substrate 105 or at least partially etched into the surface of the substrate 105. In some embodiments, the alignment structure 110 may be integrally formed within the substrate 105. In some embodiments, the alignment structure 110 may be separately formed (e.g., deposited) onto the surface of the substrate 105.

[0104] In some embodiments, substrate 105 may be compatible with the crystal molecules contained in solid crystal 115 (e.g., lattice constant matching). In some embodiments, substrate 105 may be optically transparent (e.g., having at least about 60% transmittance) at least in the visible spectrum (e.g., wavelengths ranging from about 380 nm to about 700 nm). In some embodiments, substrate 105 may also be transparent in at least a portion of the infrared (“IR”) spectrum (e.g., wavelengths ranging from about 700 nm to about 1 mm). Substrate 105 may comprise suitable materials that are substantially transparent to light in the wavelength ranges listed above, such as glass, plastic, sapphire, polymers, semiconductors, or combinations thereof. Substrate 105 may be rigid, semi-rigid, flexible, or semi-flexible. In some embodiments, substrate 105 may have one or more surfaces that are flat, raised, concave, aspherical, or free-form.

[0105] In some embodiments, substrate 105 may be part of another optical element or device, or part of another optoelectronic element or device. For example, substrate 105 may be a solid-state optical lens or part of a solid-state optical lens. In some embodiments, substrate 105 may be part of a functional device, such as a display screen. In some embodiments, substrate 105 may be used to manufacture, store, or transport optical device 100. In some embodiments, substrate 105 may be detached or removed from the rest of optical device 100 after the rest of optical device 100 has been manufactured or transported to another location or device. That is, substrate 105 may be used to manufacture, transport, and / or store to support solid crystal 115 disposed on substrate 105, and substrate 105 may be detached or removed from solid crystal 115 of optical device 100 when the manufacture of optical device 100 is completed, or when optical device 100 will be implemented in another optical device or in an optical system.

[0106] In some embodiments, solid crystal 115 may be manufactured based on one or more solid crystal materials such as anthracene, tetraphenyl, pentaphenyl, or any other saturated or unsaturated polycyclic hydrocarbons and their derivatives, nitrogen, sulfur, and oxygen heterocycles, quinoline, benzothiophene, and benzopyran, curved and asymmetric benzobenzenes such as phenanthrene, phenanthroline, pyrene, and fluoranthene and their derivatives, 2,6-naphthalenedicarboxylic acid, 2,6-dimethylformate molecules and their derivatives, biphenyl, terphenyl, tetraphenyl, or phenylacetylene or their derivatives, including substituents having alkyl groups, cyano groups, isothiocyanate groups, fluorine, chlorine, or fluorinated ethers. In some embodiments, solid crystal 115 may comprise chiral crystal molecules or crystal molecules doped with chiral dopants, and solid crystal 115 may exhibit chirality, i.e., handedness.

[0107] The solid crystal 115 may be a continuous solid crystal film, wherein adjacent lattices may be interconnected across the entire optical device 100. In some embodiments, the solid crystal 115 may be optically anisotropic, such as uniaxial or biaxial optically anisotropic. In some embodiments, the solid crystal 115 may be configured to have spatially varying or spatially uniform optical anisotropy within the continuous solid crystal 115, which may be at least partially defined, configured, or set by the alignment structure 110. In some embodiments, spatially varying or spatially uniform optical anisotropy may be generated based on the spatially varying or spatially uniform orientation of the axes of molecules contained in the solid crystal 115.

[0108] In some embodiments, the solid crystal 115 may have a first principal refractive index along a first direction and a second principal refractive index along an in-plane direction perpendicular to the first direction. In some embodiments, the first direction may be parallel to the axis of the solid crystal 115, along which the solid crystal 115 may have the highest or largest refractive index. In some embodiments, the first principal refractive index of the solid crystal 115 may be at least about 1.5, at least about 1.6, at least about 1.7, at least about 1.8, at least about 1.9, at least about 2.0, at least about 2.1, or at least about 2.2. In some embodiments, the optical anisotropy (e.g., in-plane birefringence) of the solid crystal 115 may be at least about 0.03, at least about 0.05, at least about 0.1, at least about 0.2, at least about 0.3, at least about 0.35, or at least about 0.4.

[0109] The solid-state crystal 115 can be structurally configured or manufactured to achieve at least one predetermined optical function of the optical device 100. In some embodiments, the solid-state crystal 115 can be structurally configured or manufactured to have a substantially spatially invariant (e.g., constant) orientation of its axis. In some embodiments, the solid-state crystal 115 can be structurally configured or manufactured to have a spatially varying orientation of its axis. In some embodiments, the spatially constant or spatially varying orientation of the solid-state crystal 115's axis can be achieved by aligning crystal molecules contained in the solid-state crystal 115 with a predetermined alignment pattern, such as a spatially uniform alignment pattern or a spatially varying alignment pattern. That is, the solid-state crystal 115 can be structurally configured or manufactured such that crystal molecules are aligned with a predetermined alignment pattern to provide at least one predetermined optical function.

[0110] In some embodiments, the alignment structure 110 may be configured to at least partially align crystal molecules with a predetermined alignment pattern. In some embodiments, the orientation of the axes of crystal molecules in contact with the alignment structure 110 may be aligned (or aligned with) the alignment structure 110, and the orientation of the axes of the remaining crystal molecules may be aligned based on adjacent crystal molecules already aligned and / or configured by the alignment structure 110. In some embodiments, the predetermined alignment pattern of the crystal molecules may result in a uniform orientation, periodic linear orientation, periodic radial orientation, periodic orientation, or combination thereof of the axes of crystal molecules within the solid crystal 115. Thus, the axes of the solid crystal 115 may be configured to have a constant orientation, periodic linear orientation, periodic radial orientation, periodic orientation, or combination thereof within the solid crystal 115.

[0111] Depending on the orientation of the axis of the solid crystal 115, the optical device 100 can provide different optical functions. For example, depending on the orientation of the axis of the solid crystal 115, the optical device 100 can be used as an optical waveguide, grating, prism, lens, axonopex, optical rotator, waveplate or phase retarder, lens array, prism array, or combination thereof. The optical device 100 can be used as a transmissive optical device, a reflective optical device, or a transmissive-reflective optical device. In some embodiments, when the optical device 100 is used as a transmissive optical device, the solid crystal 115 can be optically transparent (e.g., having at least about 60% transmittance) at least in the visible spectrum (e.g., about 380 nm to about 700 nm). In some embodiments, the solid crystal 115 can also be optically transparent in at least a portion of the IR spectrum, for example, having at least about 60% transmittance in the near-IR spectrum.

[0112] In some embodiments, the solid crystal 115 in the aligned crystalline state can be polarization-dependent due to optical anisotropy. For example, the solid crystal 115 can exhibit different optical functions for incident light with different polarizations. In some embodiments, the solid crystal 115 can switch between an amorphous state and an aligned crystalline state by various methods, such as polarization-based switching, thermal-based switching, or external field-based switching. In the amorphous state, the solid crystal 115 can remain solid, and the crystal molecules may not be in a predetermined alignment pattern. As a result, the solid crystal 115 in the amorphous state may not exhibit the predetermined optical function determined by the predetermined alignment pattern of the crystal molecules in the solid crystal 115. In some embodiments, the solid crystal 115 can switch between an amorphous state and an aligned crystalline state by switching the polarization of light incident on it. In some embodiments, the solid crystal 115 can switch to an amorphous state at high temperatures. In some embodiments, by applying an external field (e.g., an external optical field) to the crystal molecules in the solid crystal 115, the solid crystal 115 can switch between an amorphous state and an aligned crystalline state, wherein the external field can alter the orientation / alignment of the crystal molecules in the solid crystal 115. After the external field is removed, the crystal molecules can return to their initial orientation / alignment. For example, the crystal molecules can be aligned according to an interference pattern (e.g., formed by two beams with different polarization states). The interference pattern can produce regions of constructive or destructive interference, where the crystal molecules can be selectively aligned. For example, the crystal molecules can be aligned differently in regions of constructive or destructive interference. The orientation / alignment of the crystal molecules can be dynamically controlled by creating a holographic pattern or by actively exposing the crystal molecules and by configuring the time and length scales. That is, active orientation / alignment of the crystal molecules can be achieved.

[0113] In some embodiments, the spatial variation of the orientation of the axis of solid crystal 115 (or the spatial variation of the orientation of the axis of solid crystal 115) can be substantially smooth throughout solid crystal 115. In some embodiments, solid crystal 115 may include more than one grain (or portion) having at least one grain boundary, wherein each grain or plurality of grains may be at least partially oriented by alignment structure 110. To achieve a smooth transition between adjacent grains and crystal molecules, in some embodiments, one or more additional functional groups may be incorporated into the crystal molecules. In some embodiments, one or more additives or one or more plasticizers configured to release local crystallization strain may be added to solid crystal 115. In some embodiments, the plasticizer may include molecules having alkyl / alkoxy chains (e.g., liquid crystal molecules), which may exhibit a weak affinity for crystallinity, thereby making the crystal phase softer and more malleable to deformation and structural changes.

[0114] In some embodiments, the alignment structure 110 may include an alignment layer, which may be a separate film formed on or bonded to the substrate 105. The alignment layer may be disposed between the substrate 105 and the solid crystal 115, and may be in contact with the solid crystal 115. In some embodiments, the alignment layer may be a photoalignment material (“PAM”) layer, which may include one or more photoalignment materials. In some embodiments, the photoalignment material may include photosensitive molecules that can undergo orientation sequencing when exposed to polarized light. In some embodiments, the photosensitive molecules may include elongated anisotropic photosensitive units (e.g., fragments of small molecules or polymer molecules) that can be aligned in an alignment structure pattern when exposed to polarized light.

[0115] In some embodiments, the photosensitive unit may be polarization-sensitive. For example, the photosensitive unit may be aligned with light having a predetermined polarization and may not be aligned with light having a different polarization. In some embodiments, the alignment layer may be a mechanically rubbed layer (e.g., a mechanically rubbed polymer layer). In some embodiments, the alignment layer may be a polymer layer with anisotropic nanoimprints. In some embodiments, the alignment layer may include a ferroelectric or ferromagnetic material configured to at least partially align with crystal molecules in the solid crystal 115 in the presence of a magnetic or electric field. In some embodiments, the alignment layer may be a substantially thin crystalline film (or layer) or crystalline substrate configured to at least partially align with crystal molecules in the solid crystal 115. The crystalline film or crystalline substrate may include solid crystal molecules already aligned with an alignment structure pattern. When the crystal molecules forming the solid crystal 115 grow on the crystalline film or crystalline substrate through lattice constant matching, the growth of the crystal molecules forming the solid crystal 115 can be configured, influenced, or determined by the alignment structure pattern defined by the molecules of the crystalline film or crystalline substrate. The alignment structure pattern of the thin crystalline film or crystalline substrate can be formed using any suitable method disclosed herein. In the process of manufacturing the solid crystal 115, the crystal molecules of the solid crystal 115 can be deposited (e.g., grown) on a thin crystalline film or crystalline substrate. The crystal molecules of the solid crystal 115 in contact with the thin crystalline film or crystalline substrate can be aligned with the crystal molecules contained in the thin crystalline film or crystalline substrate. Multiple thin crystalline films or crystalline substrates can be used to form a stack of crystal molecular layers in the solid crystal 115 with different alignment patterns. In some embodiments, the alignment layer can be configured to at least partially align the crystal molecules in the solid crystal 115 based on crystallization occurring in the presence of a magnetic or electric field. In some embodiments, the alignment layer may comprise a hexagonal boron nitride (h-BN) layer or a graphene layer.

[0116] In some embodiments, the alignment structure 110 may include features formed directly on or at least partially in the substrate 105, or features formed on or at least partially in the solid crystal 115. In some embodiments, the alignment structure 110 may be generated in the solid crystal 115 based on crystallization occurring in the presence of a magnetic or electric field. In some embodiments, the alignment structure 110 may be generated in the solid crystal 115 based on an external optical field, which may at least partially align the crystal molecules in the solid crystal 115 with a predetermined alignment structure. For example, the crystal molecules contained in the solid crystal 115 may be aligned according to an interference pattern (e.g., formed by two beams with different polarization states). The interference pattern may produce regions of constructive or destructive interference, where crystal molecules may be selectively aligned. For example, crystal molecules may be differently aligned in regions of constructive or destructive interference.

[0117] In some embodiments, the substrate 105 may be nanofabricated to have an alignment structure 110 for at least partially aligning the crystal molecules in the solid crystal 115. For example, the substrate 105 may be made of an organic material, such as an amorphous polymer or liquid crystal polymer, or a crosslinkable monomer, including crosslinkable monomers with liquid crystal properties. In some embodiments, the substrate 105 may be made of an inorganic material, such as a metal or oxide used to manufacture a metasurface. The material of the substrate 105 may be isotropic or anisotropic. In some embodiments, the substrate 105 may be nanofabricated from a resist material that is transparent or nearly transparent to a range of electromagnetic frequencies, such as the visible wavelength spectrum. The resist material may be in the form of thermoplastics, polymers, optically transparent photoresists, etc. After solidification or curing, the resist material can provide alignment with the crystal molecules contained in the solid crystal 115. That is, in some embodiments, the substrate 105 may also serve as an alignment layer for at least partially aligning the crystal molecules contained in the solid crystal 115. A variety of alignment patterns and features can be achieved using nanofabrication techniques on substrate 105, allowing the creation of alignment structures 110 such that crystal molecules contained within solid crystal 115 are at least partially aligned with high customization. In some embodiments, alignment structure 110 may include anisotropic reliefs, which can be created directly on the surface of substrate 105 (e.g., ...). Figure 1A On the upper surface of the solid crystal 115 or on the surface of the solid crystal 115 (e.g., Figure 1A The substrate 105 is formed by wet etching or dry etching anisotropic relief on the lower surface of the solid crystal 115. In some embodiments, the substrate 105 may be a substantially thin crystalline substrate configured to at least partially align the crystal molecules contained in the solid crystal 115, and the substrate 105 may serve as the alignment structure 110.

[0118] In some implementation schemes, such as Figure 1BAs shown, the optical device 150 may include two alignment structures 110a and 110b sandwiching a solid crystal 115. The solid crystal 115 may be in contact with both alignment structures 110a and 110b. Alignment structures 110a and 110b may be configured to at least partially align crystal molecules contained in the solid crystal 115 with a predetermined alignment pattern. In some embodiments, the orientation of the axes of crystal molecules in contact with alignment structures 110a and 110b may be determined by alignment structures 110a and 110b, respectively. The orientation of the axes of other crystal molecules contained in the solid crystal 115 may be determined based on adjacent crystal molecules in contact with and / or aligned with alignment structures 110a and / or 110b. The two alignment structures 110a and 110b may each define an alignment structure pattern or have an alignment structure pattern. The alignment patterns of the two alignment structures 110a and 110b can be the same or different.

[0119] Return to Figure 1A In some embodiments, the optical device 100 may include other elements. For example, the substrate 105 may have a first surface (e.g., on...). Figure 1A The upper surface shown in the view) and the opposite second surface ( Figure 1A (The lower surface in the view shown). A solid crystal 115 may be disposed on a first surface of the substrate 105. In some embodiments, the optical device 100 may further include a reflective cladding layer disposed on a second surface of the substrate 105. The solid crystal 115 may have a first surface (e.g., Figure 1A The upper surface in the view shown) and the opposite second surface (e.g., Figure 1A (Lower surface in the view shown). In some embodiments, the optical device 100 may include an anti-reflective coating disposed on at least one of the first or second surfaces of the solid crystal 115. In some embodiments, the optical device 100 may include two substrates disposed opposite to each other. For example, the second substrate may be disposed on the alignment structure 110.

[0120] Similarly, Figure 1B The illustrated optical device 150 may include other elements. For example, a reflective cladding layer may be disposed on the lower surface of the substrate 105 (the surface opposite to the surface on which the alignment structure 110a is disposed). An antireflective cladding layer may be disposed on at least one of the upper or lower surfaces of the solid crystal 115. In some embodiments, the optical device 150 may include a second substrate disposed on the alignment structure 110b.

[0121] For the purpose of explanation, Figure 1A and Figure 1BA solid crystal 115 is shown. The number of solid crystals (e.g., solid crystal films, layers, or plates) included in optical devices 100 or 150 can be any suitable number, such as two, three, four, five, six, etc. In some embodiments, the number of alignment structures (e.g., alignment layers) included in optical devices 100 or 150 may not be limited to one or two, and may be more than two, such as three, four, five, six, etc. The number of solid crystals (e.g., solid crystal films, layers, or plates) and alignment structures that can be included in optical devices 100 or 150 can be determined based on a specific application. For example, optical devices 100 or 150 may include a stack of multiple consecutive solid crystals (e.g., solid crystal films, layers, or plates) and multiple alignment structures (e.g., alignment layers) arranged alternately. Crystal molecules contained in a solid crystal can be at least partially aligned by a corresponding alignment structure on which the crystal molecules are disposed. For example, crystal molecules in a solid crystal film can be at least partially aligned by an alignment structure on which the solid crystal film is disposed. In some embodiments, multiple alignment structures may be identical. For example, multiple alignment structures can be configured to at least partially align crystal molecules contained in respective solid crystal films with substantially the same predetermined alignment pattern. In some embodiments, at least two of the multiple alignment structures can be different from each other. For example, at least two of the multiple alignment structures can be configured to at least partially align crystal molecules contained in at least two corresponding solid crystal films with at least two different predetermined alignment patterns. In some embodiments, when the stack thickness is greater than or equal to a predetermined thickness, the multiple alignment structures can provide the advantage of resetting or realigning the orientation of crystal molecules in the respective solid crystal films.

[0122] In some embodiments, multiple solid-state crystal films may comprise the same solid crystal. In some embodiments, at least two of the multiple solid-state crystal films may comprise different solid crystals. For example, the solid crystals may have different optical dispersions (e.g., different birefringence dispersions). For example, two solid-state crystal films comprising solid crystals with positive and negative birefringence dispersions, respectively, may compensate for each other, resulting in a substantially achromatic optical device within a predetermined wavelength range (e.g., the visible wavelength range). In some embodiments, a single solid-state crystal film may comprise a combination of a first solid-state crystal material having positive birefringence dispersion and a second solid-state crystal material having negative birefringence dispersion, resulting in a substantially achromatic optical device within a predetermined wavelength range.

[0123] Furthermore, organic solid crystals comprising continuous volumes of organic single crystals or polycrystalline structures can be formed. In some embodiments, the organic solid crystal has a size of not less than 100 micrometers in one dimension and a size of not less than 30 millimeters in the other two dimensions. In some embodiments, the first high refractive index is in the range of 1.6 to 2.6, and the optical anisotropy is greater than 0.1.

[0124] Figure 1C The illustrations depict the orientation of anisotropic refractive indices on flat and curved substrates according to various embodiments. In some embodiments, the orientation of the first refractive index is perpendicular to any in-plane direction or parallel to one of the in-plane directions, such as... Figure 1C As shown. For example, in Figure 1C In Part I and Part II, the refractive index n e Parallel to one of the directions within the plane, as indicated by arrow 160-1 for flat surfaces and arrow 160-2 for non-flat surfaces. As another example, in... Figure 1C In Parts III and IV, the refractive index n e Perpendicular to the surface, as indicated by arrow 160-3 for flat surfaces and arrow 160-4 for non-flat surfaces (e.g., refractive index n). e A portion parallel to the surface. Figure 1D The dimensions of a solid crystal 115 (e.g., a continuous-volume organic single crystal or polycrystalline structure) according to some embodiments are schematically illustrated. Figure 1A In the diagram, the solid crystal 115 is shown together with the alignment structure 110 and the substrate 105. However, it should be understood that the solid crystal 115 can also be a separate optical device, such as... Figure 1D The solid crystal 115 is shown in the figure. For example, the solid crystal 115 is fabricated on a substrate 105 having an alignment structure 110, and is separated from the substrate 105 and / or the alignment structure 110 after fabrication (e.g., broken apart). In some embodiments, the solid crystal 115 has a first dimension of not less than 100 micrometers (e.g., Figure 1D Dimension D2) and a second dimension different from the first dimension (e.g., not less than 1 cm, 2 cm, or 3 cm) (e.g., Figure 1D (Dimension D1 or Dimension D3 in the text).

[0125] In some embodiments, the continuous volume organic single-crystal or polycrystalline structure (e.g., solid crystal 115) includes at least one of the following polycyclic aromatic hydrocarbon molecules: naphthalene, anthracene, tetraphenylene, pentaphenylene, pyrene, polycene, fluoranthene, benzophenone, benzochromene, benzoyl, benzimazole, benzene, hexachlorobenzene, nitropyridine-N-oxide, benzene-1,4-dicarboxylic acid, diphenylacetylene, N-(4-nitrophenyl)-(s)-prolinal, 4,5-dicyanimazole, benzodithiophene, cyanopyridine, thienothiophene, stilbene, azobenzene and its derivatives.

[0126] In some embodiments, the continuous-volume organic single-crystal or polycrystalline structure comprises a molecule containing a cyclic structure system and two terminal group systems. The cyclic structure system includes saturated cyclic groups such as cyclohexane, cyclopentane, tetrahydropyran, piperidine, tetrahydrofuran, pyrrolidine, tetrahydrothiophene, and their derivatives. The cyclic structure system also includes unsaturated aromatic groups such as benzene, naphthalene, anthracene, thiophene, biphenyl, diphenylacetylene, benzimidazole, diphenylacetylene, cyanopyridine, thienothiophene, dibenzothiophene, carbazole, silanium, and their derivatives. The terminal group system includes one or more C1-C10 alkyl, alkoxy, alkenyl, -CN, -NCS, -SCN, -SF5, -Br, -Cl, -F, -OCF3, -CF3, monofluorinated or polyfluorinated C1-C... 10 Alkyl groups or alkoxy groups.

[0127] In some embodiments, the continuous volume organic single-crystal or polycrystalline structure comprises a crystalline polymer having a precursor with aromatic or heteroaromatic groups and their derivatives. Examples of such polymers include polyethylene naphthalate, poly(vinylphenyl sulfide), poly(α-methylstyrene), polythiophene, polythiophene, poly(n-vinylphthalimide), poly(p-xylene), polysulfides, polysulfones, poly(bromophenyl), poly(vinylnaphthalene), and liquid crystal polymers having precursors with the functional groups (e.g., terminal groups) described above.

[0128] In some embodiments, the continuous volume organic single-crystal or polycrystalline structure comprises an amorphous polymer having aliphatic, heteroaliphatic, aromatic, or heteroaromatic groups (e.g., polystyrene) as a binder. In some embodiments, the organic solid crystal layer comprises additives such as fatty acids, lipids, plasticizers, and surfactants (e.g., molecules having monofluorinated or polyfluorinated alkyl or alkoxy groups).

[0129] In some embodiments, the continuous volume organic single-crystal or polycrystalline structure is formed by one or more organic crystal molecules, said organic crystal molecules being selected from formulas 1-1 to 1-46, and formulas 2-1 to 1-46.

[0130] The group consisting of organic crystal molecules of formulas 2-4 and 3-1 to 3-28:

[0131]

[0132]

[0133]

[0134]

[0135] R is independently selected from the group consisting of: CH3, H, OH, methoxy (OMe), ethoxy (OEt), isopropoxide (OiPr), F, Cl, Br, I, Ph, NO2, SO3, SO2Me, isopropyl (iPr), propyl (Pr), tert-butyl (t-Bu), sec-butyl (sec-Bu), ethyl (Et), acetyl, SH, S-methyl (SMe), carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, N-dimethyl (NMe2), N-methyl (NMeH), and C2H2.

[0136]

[0137]

[0138]

[0139] R1 is independently selected from the following groups: CH3, H, OH, OMe, OEt, OiPr, F, Cl, Br, I, Ph, NO2, SO3, SO2Me, iPr, Pr, t-Bu, sec-Bu, Et, acetyl, SH, SMe, carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, NMe2, NMeH and C2H2, where n is greater than or equal to 1 and n1 is greater than or equal to zero.

[0140]

[0141]

[0142]

[0143] R2 is independently selected from the group consisting of: CH3, H, OH, OMe, OEt, OiPr, F, Cl, Br, I, Ph, NO2, SO3, SO2Me, iPr, Pr, t-Bu, sec-Bu, Et, acetyl, SH, SMe, carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, NMe2, NMeH, and C2H2, and n1 is greater than or equal to zero. *Enantiomerically pure compounds or racemic mixtures. **Examples of bridging functional groups. ***Examples of acceptor functional groups. ****Examples of donor functional groups.

[0144] In some embodiments, the continuous-volume organic single-crystal or polycrystalline structure is formed of an organic salt comprising a combination of anionic molecules (e.g., formulas 5-1 to 5-11 below) and cationic molecules (e.g., formulas 5-12 to 5-25 below). In some embodiments, at least one of the anionic or cationic molecules is organic (e.g., the anionic molecule is organic while the cationic molecule is not organic, the cationic molecule is organic while the anionic molecule is not organic, or both the anionic and cationic molecules are organic). In some embodiments, the continuous-volume organic single-crystal or polycrystalline structure comprises a combination of anionic molecules selected from formulas 5-1 to 5-11 and cationic molecules selected from formulas 5-12 to 5-25.

[0145]

[0146]

[0147]

[0148] R3 is independently selected from the following groups: CH3, H, OH, OMe, OEt, OiPr, F, Cl, Br, I, Ph, NO2, SO3, SO2Me, iPr, Pr, t-Bu, sec-Bu, Et, acetyl, SH, SMe, carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, NMe2, NMeH, and C2H2. *Anionic molecules. **Cation molecules.

[0149] In some implementations, a continuous volume organic single-crystal or polycrystalline structure is incorporated in the alignment layer (e.g., Figure 1A The alignment layer is formed on the alignment structure 110 in the embodiment. In some embodiments, the alignment layer includes a controlled nucleation surface (e.g., on a surface such as...). Figure 1AThe substrate 105 has more than one controlled nucleation site on its surface. In some embodiments, the controlled nucleation surface includes a non-polymer-based coating layer selected from silyl fluoride groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, heteroaromatic groups, small organic molecule-based crystals, and any one of Formulas 6-1 to 6-5.

[0150]

[0151] R3 is independently selected from the group consisting of: CH3, H, OH, OMe, OEt, OiPr, F, Cl, Br, I, Ph, NO2, SO3, SO2Me, iPr, Pr, t-Bu, sec-Bu, Et, acetyl, SH, SMe, carboxyl, aldehyde, amide, nitrile, ester, SO2NH3, NH2, NMe2, NMeH, and C2H2. *Enantiomerically pure compounds or racemic mixtures of sugars, open-ring or closed-ring. **Enantiomerically pure compounds or racemic mixtures.

[0152] Figures 2A-2D The diagram schematically illustrates xz-sectional views of optical devices according to various embodiments. Figures 2A-2D In the illustrated embodiment, the crystal molecules in the corresponding solid crystal film can be substantially uniformly aligned with a predetermined alignment pattern (e.g., a predetermined orientation). Figures 2A-2D The optical devices shown may include those with Figure 1A The optical device 100 shown or Figure 1B The optical device 150 shown includes structures or elements that are the same as or similar to those in the optical device 150. Figures 2A-2D The description of the same or similar structures or elements included in the illustrated embodiments can be referenced from the above description, including combinations Figure 1A and Figure 1B The implementation scheme shown is described.

[0153] like Figure 2AAs shown, the optical device 200 may include a substrate 201, an alignment structure 202 disposed on the substrate 201 (e.g., disposed on or at least partially disposed in the substrate 201), and a solid crystal film 203 disposed on the alignment structure 202 (e.g., disposed on the alignment structure 202). The solid crystal film 203 may be in the form of a film, layer, or plate. For ease of discussion, the solid crystal 203 may also be referred to as a solid crystal 203 or a solid crystal layer 203. For illustrative purposes, the substrate 201, the alignment structure 202, and the solid crystal film 203 are shown as having a flat shape. In some embodiments, at least one of the substrate 201, the alignment structure 202, or the solid crystal film 203 may have a curved shape. The solid crystal film 203 may be in contact with the alignment structure 202, and the crystal molecules 204 contained in the solid crystal film 203 may be at least partially aligned by the alignment structure 202. In some embodiments, each layer of crystal molecules 204 contained in the solid crystal film 203 may be planarly located on the alignment structure 202 in the xy plane, and may follow an orientation or alignment direction 205 (as shown by...) in the xy plane perpendicular to the thickness direction 206 (e.g., the z-axis direction) of the solid crystal film 203. Figure 2A (The arrows shown indicate this). For example, crystal molecules 204 can be spatially uniformly aligned along the x-axis, as... Figure 2A As shown. Multiple layers of crystalline molecules 204 can be arranged (e.g., grown) along the z-axis to form a solid crystalline film 203. For the purposes of discussion, each molecule 204 is depicted as having a longitudinal direction (or length direction) and a transverse direction (or width direction), and the axis of the molecule 204 is assumed to be along the assumed axis of the highest refractive index of the molecule 204 in the longitudinal direction of the molecule 204. Figure 2A As shown, the orientation of the axes of molecule 204 is uniformly aligned in alignment direction 205 by alignment structure 202. That is, different layers of molecule 204 can be aligned substantially in the same alignment direction 205. The plane including the longitudinal and transverse directions of molecule 204 is parallel to the surface of substrate 201 or the xy plane (i.e., molecule 204 lies flatly in the xy plane). For illustrative purposes, the crystal molecules 204 in solid crystal film 203 or solid crystal layer 203 are drawn to have the same shape. In some embodiments, the crystal molecules 204 in solid crystal layer can be identical (e.g., molecules of the same crystalline material). In some embodiments, the crystal molecules 204 in a solid crystal layer can include two or more different molecules (e.g., molecules of two or more different crystalline materials).

[0154] like Figure 2BAs shown, the optical device 220 may include a solid crystal film 223. Crystal molecules 224 contained in the solid crystal film 223 may be at least partially aligned via an alignment structure 222. Figure 2A In the illustrated embodiment, the crystal molecules 204 are planarly located on the xy plane (e.g., a plane including the longitudinal and transverse directions of the crystal molecules 204 is parallel to the surface of the substrate 201, or the xy plane). Figure 2B In the illustrated embodiment, the crystal molecules 224 may be non-planar on the xy-plane, but may be planar on the xz-plane. That is, the plane including the longitudinal and transverse directions of the crystal molecules 204 may be perpendicular to the surface of the substrate 221, or the xy-plane. Each layer of crystal molecules 224 may follow an orientation or alignment direction 225 (as shown in the diagram) in the xy-plane perpendicular to the thickness direction 226 (e.g., the z-axis direction) of the solid crystal film 223. Figure 2B (The arrows shown indicate this). For example, crystal molecules 224 can be spatially uniformly aligned along the x-axis, as... Figure 2B As shown. In other words, the orientation of the axis of molecule 224 can be uniformly aligned through the alignment structure 222. That is, different layers of molecule 224 can be uniformly aligned in the same alignment direction 225.

[0155] like Figure 2C As shown, the optical device 240 may include a solid crystal film 243. Crystal molecules 244 contained in the solid crystal film 243 may be at least partially aligned by an alignment structure 242. The longitudinal direction (e.g., the orientation of the axis) of each crystal molecule 244 in the xz plane may form an angle relative to the surface of the substrate 241 (or the surface of the alignment structure 242). For example, the crystal molecules 244 may follow an orientation or alignment direction 245 in the xz plane (as shown by...). Figure 2C (Indicated by the arrow shown). That is, the orientation of the axis of molecule 244 can be uniformly aligned in the alignment direction 245 in the xz plane, forming a suitable angle relative to the surface of substrate 241 (or the surface of alignment structure 242). The angle of crystal molecule 244 relative to the surface of substrate 241 (e.g., the orientation of the axis of molecule 244) can be any suitable angle, such as 30°, 45°, etc. In some embodiments, crystal molecules 244 contained in solid crystal film 243 can have other suitable orientations or alignment directions under appropriate crystal growth conditions. For example, crystal molecules 244 can follow the orientation or alignment direction in the thickness direction (e.g., the z-axis direction) of solid crystal film 243.

[0156] like Figure 2DAs shown, the optical device 260 may include a stack of multiple consecutive solid crystal films and multiple alignment structures (e.g., alignment layers) arranged alternately. For illustrative purposes, two solid crystal films 263a and 263b and two alignment structures 262a and 262b are shown as included in the optical device 260. Crystal molecules 264a contained in solid crystal film 263a can be at least partially aligned by alignment structure 262a, and crystal molecules 264b contained in solid crystal film 263b can be at least partially aligned by alignment structure 262b. The multiple alignment structures may define the same or different predetermined alignment patterns for aligning crystal molecules disposed thereon. Figure 2D In the illustrated embodiment, the two alignment structures can provide substantially the same alignment pattern for the crystal molecules contained in the respective solid crystal films. For example, crystal molecules 264a and 264b can be aligned in the x-axis directions 265a and 265b, as shown. Figure 2D As shown. Although each solid crystal film 263a and 263b is shown as similar to Figure 2B The solid crystal film 223 is shown, but in some embodiments, each solid crystal film 263a and 263b may be similar to Figure 2A The solid crystal film 203 shown Figure 2C The solid crystal film 243 shown.

[0157] Figure 3A and Figure 3B A schematic diagram illustrates a top view (e.g., an xy-section view) of an optical device according to various embodiments. Figure 3A and Figure 3B In the illustrated embodiment, the crystal molecules in the corresponding solid crystal film can be substantially uniformly aligned in a predetermined pattern (e.g., in a predetermined direction). Figure 3A and Figure 3B The optical devices shown may include those with Figures 1A-2D The optical devices shown (e.g., Figure 1A The optical device 100 shown includes structures or elements that are the same as or similar to those in the optical device 100 shown. Figure 3A and Figure 3B The description of the same or similar structures or elements included in the illustrated embodiments can be referenced to the above description (including, for example, combinations thereof). Figure 1A The implementation scheme shown is described below. Figure 3A and Figure 3B The specific orientation of molecules in the top view is for illustrative purposes.

[0158] like Figure 3AAs shown, the optical device 300 may include a substrate 301, an alignment structure 302 disposed on the substrate 301 (e.g., disposed on the substrate 301), and a solid crystal film 303 disposed on the alignment structure 302 (e.g., disposed on the alignment structure 202). The solid crystal film 303 may be in contact with the alignment structure 302. Crystal molecules 304 contained in the solid crystal film 303 may be at least partially aligned by the alignment structure 302. The crystal molecules 304 contained in the solid crystal film 303 may be planarly located on the alignment structure 302 and may follow an orientation or alignment pattern (e.g., direction 305) in a plane (e.g., the xy plane) perpendicular to the thickness direction (e.g., the z-axis) of the solid crystal film 303. Figure 3A (The arrows shown indicate this). For example, crystal molecule 304 can move along... Figure 3A The crystal molecules are aligned along the x-axis. In other words, the orientation of the molecular axes can be aligned in alignment direction 305. In some embodiments, the crystal molecules 304 can be aligned along the y-axis. In some embodiments, the crystal molecules 304 can be aligned in a suitable direction within the xy-plane. In some embodiments, having... Figure 3A The optical device 300 shown in the top view can have Figure 2A The corresponding cross-sectional view is shown.

[0159] like Figure 3B As shown, the optical device 320 may include a substrate 321, an alignment structure 322 disposed on the substrate 321 (e.g., disposed on the substrate 321), and a solid crystal film 323 disposed on the alignment structure 322 (e.g., disposed on the alignment structure 322). Crystal molecules 324 contained in the solid crystal film 323 may be planarly located on the alignment structure 322 and may follow an orientation or alignment pattern (e.g., direction 325) in a plane (e.g., the xy plane) perpendicular to the thickness direction (e.g., the z-axis) of the solid crystal film 323. Figure 3B (The arrows shown indicate this). In other words, the orientation of the molecular axes can be aligned in alignment direction 325. Alignment direction 325 can form an angle relative to the x-axis or y-axis. Any suitable angle can be configured. For example, in some embodiments, crystal molecules 324 can be aligned in a direction having an angle of approximately 45° relative to the x-axis direction.

[0160] Figures 4A-4C The diagram schematically illustrates the xz cross-sectional views of an optical device according to various embodiments. Figures 4A-4C The optical device shown may include a curved substrate and a curved solid crystal film, and can be used as a curved optical waveguide. Figures 4A-4C The optical devices shown may include those with Figures 1A-3B The optical devices shown (e.g., Figure 1AThe optical device 100 shown includes structures or elements that are the same as or similar to those in the optical device 100 shown. Figures 4A-4C The description of the same or similar structures or elements included in the illustrated embodiments can be referenced to the above description (including, for example, combinations thereof). Figure 1A The implementation scheme shown is described below.

[0161] like Figure 4A As shown, the optical device 400 may include a substrate 401, an alignment structure 402 disposed on the substrate 401 (e.g., disposed on the substrate 401), and a solid crystal film 403 disposed on the alignment structure 402 (e.g., disposed on the alignment structure 402). The solid crystal film 403 may be in contact with the alignment structure 402. Crystal molecules 404 contained in the solid crystal film 403 may be at least partially aligned by the alignment structure 402. The crystal molecules 404 contained in the solid crystal film 403 may have a substantially uniform orientation or alignment in the solid crystal film 403. The substrate 401 may include one or more curved surfaces. For example, one or both of the upper and lower surfaces of the substrate 401 may have a curved shape. In some embodiments, the alignment structure 402 disposed on the substrate 401 may include one or more curved surfaces. For example, at least the lower surface of the alignment structure 402 facing the upper surface of the substrate 401 may have a curved shape. The bending shape of the alignment structure 402 can match the bending shape of the upper surface of the substrate 401. In some embodiments, such as Figure 4A As shown, both the substrate 401 and the alignment structure 402 can have a raised shape. In some embodiments, the alignment structure 402 can be formed directly (e.g., etched) on the curved surface of the substrate 401.

[0162] The solid crystal film 403 may have a first surface and an opposing second surface. One or both of the first and second surfaces of the solid crystal film 403 may be non-linear. In some embodiments, both the first and second surfaces of the solid crystal film 403 may be non-linear. For example, both the first surface (e.g., the upper surface) and the second surface (e.g., the lower surface) of the solid crystal film 403 may have a curved shape that matches the curved shape of the alignment structure 402. For example, as Figure 4AAs shown, the solid crystal film 403 may have a protrusion shape that matches the protrusion shape of the substrate 402. The solid crystal film 403 may guide electromagnetic radiation (e.g., light) via TIR for internal propagation within the solid crystal film 403. In some embodiments, the solid crystal film 403 may be grown on the top surface of the substrate 401. The growth process may include first setting an alignment structure 402 on the top surface of the substrate 401, and then epitaxially depositing (e.g., growing) crystal molecules 404 on the alignment structure 402. In some embodiments, the front surface (or top surface) and the opposing rear surface (or bottom surface) of the solid crystal film 403 may not be parallel to each other.

[0163] like Figure 4B As shown, the optical device 420 may include a substrate 421 with a concave shape, an alignment structure 422 with a concave shape, and a solid crystal film 423 with a concave shape. Although in Figure 4B In the illustrated embodiment, the alignment structure 422 is shown as a separate element disposed on the substrate 421, but in some embodiments, the alignment structure 422 may be formed directly (e.g., etched) on a curved surface of the substrate 421. The alignment structure 422 may be configured to at least partially align solid crystal molecules 423 with a predetermined alignment pattern.

[0164] like Figure 4C As shown, the optical device 440 may include a curved (e.g., concave) solid crystal film 443. In some embodiments, the curved solid crystal film 443 can be obtained by forming a meniscus during the crystal growth process. Crystal molecules 444 can be aligned based on the shape of the meniscus during the growth process. In some such embodiments, the alignment structure and substrate may be omitted during the fabrication process of the solid crystal film 443.

[0165] Figure 5A The diagram schematically illustrates an xz cross-sectional view of an optical waveguide 500 having input coupling elements and output coupling elements according to some embodiments. Figure 5A The optical waveguide 500 shown may include and Figures 1A-4C The optical devices shown include structures or elements that are the same as or similar to those in the optical device. Figure 5A The description of the same or similar structures or elements included in the illustrated embodiments can be referenced to the above description (including, for example, combinations thereof). Figure 1A The implementation scheme shown is described below.

[0166] like Figure 5AAs shown, the optical waveguide 500 can be a curved optical waveguide. The optical waveguide 500 may include a substrate 501, an alignment structure 502 disposed at (e.g., on) the substrate 501, and a solid crystal film (or solid crystal) 503 disposed at (e.g., on) the alignment structure 502. The solid crystal film 503 may be in contact with the alignment structure 502. Crystal molecules 504 in the solid crystal film 503 can be at least partially aligned by the alignment structure 502. For example, the crystal molecules 504 contained in the solid crystal film 503 may be substantially uniformly aligned within the solid crystal film 503. In other words, the alignment structure 502 may include an alignment structure pattern or define an alignment structure pattern for aligning at least a portion of the crystal molecules 504 disposed on the alignment structure 502. In some embodiments, the crystal molecules 504 may be aligned with a uniform predetermined alignment pattern, such as... Figure 5A As shown. In some embodiments, the thickness of the optical waveguide 500 can be from about 300 μm to about 1 mm, and at least one lateral dimension of the optical waveguide 500 can be from about 30 mm to about 100 mm.

[0167] Optical waveguide 500 can be configured to receive input light 507 at one or more input coupling elements 505 disposed on a side (e.g., top) of optical waveguide 500. The wavelength of the input light 507 can be in the visible spectrum or near-IR spectrum. One or more input coupling elements 505 can be configured to couple the input light 507 into optical waveguide 500 as input coupling light 508. Optical waveguide 500 can guide the input coupling light 508 to one or more output coupling elements 506 disposed on optical waveguide 500 via total internal reflection (“TIR”). Input coupling light 508 can also be referred to as total internal reflection light 508. One or more output coupling elements 506 can be disposed on a side (e.g., top) away from one or more input coupling elements 505. One or more output coupling elements 506 can be configured to couple the input coupling light 508 out of optical waveguide 500 as output light 509, which can be transmitted to a user's eye or other optical element. Figure 5A In the illustrated embodiment, one or more input coupling elements 505 and one or more output coupling elements 506 are disposed on the same side or surface of the optical waveguide 500. In some embodiments, one or more input coupling elements 505 and one or more output coupling elements 506 may be disposed on different sides or surfaces of the optical waveguide 500.

[0168] The optical waveguide 500 may include a first surface (or side surface) 500-1 and an opposing second surface (or side surface) 500-2. The solid crystal film 503 may include a first surface (or side surface) 503-1 and an opposing second surface (or side surface) 503-2. The substrate 501 may include a first surface (or side surface) 501-1 and an opposing second surface (or side surface) 501-2. In some embodiments, the first surface (or side surface) 500-1 of the optical waveguide 500 may also be the first surface (or side surface) 503-1 of the solid crystal film 503, and the second surface (or side surface) 500-2 of the optical waveguide 500 may also be the second surface (or side surface) 501-2 of the substrate 501.

[0169] In some embodiments, the input coupling element 505 may be disposed at a first surface 500-1 or a second surface 500-2 of the optical waveguide 500. For example, in some embodiments, the input coupling element 505 may be an integral part of the first surface 500-1 or the second surface 500-2. In some embodiments, the input coupling element 505 may be a separate element attached to, combined with, coupled to, or otherwise coupled to the first surface 500-1 or the second surface 500-2.

[0170] In some embodiments, the output coupling element 506 may be disposed on the first surface 500-1 or the second surface 500-2 of the optical waveguide 500. For example, in some embodiments, the output coupling element 506 may be an integral part of the first surface 500-1 or the second surface 500-2. In some embodiments, the output coupling element 506 may be a separate element attached to, combined with, coupled to, or otherwise coupled to the first surface 500-1 or the second surface 500-2. In some embodiments, the input coupling element 505 and the output coupling element 506 may be disposed on the same surface or different surfaces of the optical waveguide 500. In some embodiments, although not explicitly stated... Figure 5A As shown, at least one of the input coupling element 505 or the output coupling element 506 may be disposed at the second surface 500-2 of the optical waveguide 500.

[0171] In some embodiments, the input coupling element 505 and the output coupling element 506 can be disposed on the same surface or different surfaces of the solid crystal film 503. For example, although Figure 5AThe diagram shows an input coupling element 505 and an output coupling element 506 disposed on a first surface 503-1 of a solid-state crystal film 503. However, at least one of the input coupling element 505 and the output coupling element 506 may be disposed on a second surface 503-2 of the solid-state crystal film 503. In some embodiments, the input coupling element 505 and the output coupling element 506 may be disposed on the same surface or different surfaces of the substrate 501. For example, at least one of the input coupling element 505 or the output coupling element 506 may be disposed on the first surface 501-1 or the second surface 501-2 of the substrate 501. In some embodiments, when one of the input coupling element 505 or the output coupling element 506 is disposed on the second surface (side surface) 501-2 of the substrate 501, the other of the input coupling element 505 or the output coupling element 506 may be disposed on the first surface (side surface) 503-1 of the solid-state crystal film 503. The input coupling element 505 and the output coupling element 506 can be disposed at a combination of multiple locations, including the first surface 503-1 of the solid crystal film 503, the second surface 503-2 of the solid crystal film 503, the first surface of the alignment structure 502 facing the solid crystal film 503, the second surface of the alignment structure 502 facing the substrate 501, the first surface 501-1 of the substrate, or the second surface 501-2 of the substrate 501.

[0172] In some embodiments, the input coupling element 505 may include a one-dimensional (“1D”) diffraction grating or a two-dimensional (“2D”) diffraction grating, which may be referred to as an input coupling diffraction grating. A 1D diffraction grating can diffract a beam along one axis, and a 2D diffraction grating can diffract a beam along two axes. In some embodiments, a 2D diffraction grating can be generated by orthogonally overlapping two 1D grating structures. The spacing of the input coupling diffraction gratings can be configured such that the input coupling diffraction gratings can be configured to couple input light 507 into the optical waveguide 500 at a suitable angle via diffraction, and the input coupled light 508 can propagate within the optical waveguide 500 via TIR. In some embodiments, the output coupling element 506 may include a 1D diffraction grating or a 2D diffraction grating, which may be referred to as an output coupling diffraction grating. The spacing of the output coupling diffraction gratings can be configured such that they can diffractically couple light 508 propagating within the optical waveguide 500 via TIR out of the waveguide 500. In some embodiments, at least one of the input coupling diffraction gratings or the output coupling diffraction grating can be polarization-dependent. For example, at least one of the input coupling diffraction gratings or the output coupling diffraction grating can selectively diffract light with a first polarization and transmit light with a different polarization in the absence of negligible or no diffraction.

[0173] In some embodiments, at least one of the input-coupled diffraction grating or the output-coupled diffraction grating may include a 1D periodic structure or a 2D periodic structure (e.g., a ridge) configured (e.g., etched) in the substrate 501 or the solid crystal film 503. In some embodiments, a 1D periodic ridge or a 2D periodic ridge may be configured (e.g., etched) in the substrate 501 or the solid crystal film 503. Figure 5A In the upper portion of the substrate 501 shown. In some embodiments, 1D periodic ridges or 2D periodic ridges can be configured (e.g., etched) in Figure 5A In the upper and / or lower portions of the solid crystal film 503 shown. In some embodiments, at least one of the input coupling diffraction grating or the output coupling diffraction grating may include a 1D periodic ridge or a 2D periodic ridge configured (e.g., etched) in a separate polymer or glass disposed at the optical waveguide 500. In some embodiments, at least one of the input coupling diffraction grating or the output coupling diffraction grating may be formed from a volume hologram recorded with a photosensitive material.

[0174] Figure 5B The diagram schematically illustrates an xz cross-sectional view of an optical waveguide 520 having input coupling elements and output coupling elements according to some embodiments. Figure 5B The optical waveguide 520 shown may include and Figures 1A-4C The optical devices shown (e.g., Figure 2D The optical device 260 shown may include structures or elements that are the same as or similar to those in the optical device 260. The optical waveguide 520 may include structures or elements that are similar to those in the optical device 260. Figure 5A The optical waveguide 500 shown includes structures or elements that are the same as or similar to those in the waveguide. Figure 5B The description of the same or similar structures or elements included in the illustrated implementation can be found in the above description.

[0175] like Figure 5B As shown, the optical waveguide 520 can be a planar optical waveguide. The optical device 520 may include a stack of multiple consecutive solid crystal films and multiple alignment structures arranged alternately. Crystal molecules contained in the solid crystal films can be at least partially aligned by the alignment structures on which the solid crystal films are disposed. For illustrative purposes, Figure 5BThe optical device 520 shown may include a substrate 521, a first solid-state crystal film 523a and a second solid-state crystal film 523b, and a first alignment structure 522a and a second alignment structure 522b. The first alignment structure 522a may be disposed on the surface of the substrate 521 (e.g., the top surface of the substrate 521). The first solid-state crystal film 523a may be disposed on the surface of the first alignment structure 522a (e.g., the top surface of the first alignment structure 522a). The second alignment structure 522b may be disposed on the surface of the first solid-state crystal film 523a (e.g., the top surface of the first solid-state crystal film 523a). The second solid crystal film 523b can be disposed on the surface of the second alignment structure 522b (e.g., the top surface of the second alignment structure 522b).

[0176] The first alignment structure 522a may include or define a first alignment structure pattern for aligning at least a portion, or at least partially, of the crystal molecules 524a contained in the first solid crystal film 523a. The crystal molecules 524a may be aligned with a first predetermined alignment pattern, which may be the same as or different from the first alignment structure pattern. The second alignment structure 522b may include or define a second alignment structure pattern for aligning at least a portion, or at least partially, of the crystal molecules 524b contained in the second solid crystal film 523b. The crystal molecules 524b may be aligned with a second predetermined alignment pattern, which may be the same as or different from the second alignment structure pattern. The first alignment structure pattern may be the same as or different from the second alignment structure pattern. In other words, the first alignment structure may be the same as or different from the second alignment structure.

[0177] The crystal molecules 524a contained in the first solid crystal film 523a may or may not have the same properties as the crystal molecules 524b contained in the second solid crystal film 523b. In some embodiments, crystal molecules 524a may be crystal molecules of the same type as crystal molecules 524b. In some embodiments, crystal molecules 524a may be aligned with a first predetermined alignment pattern, and crystal molecules 524b may be aligned with a second predetermined alignment pattern. The first predetermined alignment pattern may be the same as the second predetermined alignment pattern, or it may be different from the second predetermined alignment pattern. Figure 5B In the illustrated embodiment, the crystal molecules 524a contained in the first solid crystal film 523a and the crystal molecules 524b contained in the second solid crystal film 523b are aligned with the same predetermined alignment pattern (e.g., the same predetermined orientation, such as...). Figure 5B The x-axis direction shown is uniformly aligned in space.

[0178] Optical waveguide 520 may include one or more input coupling elements 525 configured to couple input light 527 into optical waveguide 520. The input coupled light 527 may propagate within optical waveguide 520 as light 528 via TIR. Optical waveguide 520 may include one or more output coupling elements 526 configured to couple light 528 out of optical waveguide 520 as output light 529. Input coupling elements 525 and output coupling elements 526 may be disposed at multiple locations combined within optical waveguide 520. For example, as... Figure 5B As shown, the input coupling element 525 and the output coupling element 526 can be respectively disposed on the first side (surface) 523b-1 of the second solid crystal film 523b and the second side (surface) 523a-2 of the first solid crystal film 523a. In some embodiments, the input coupling element 525 and the output coupling element 526 can each include one or more 1D diffraction gratings or 2D diffraction gratings.

[0179] In some embodiments, the optical waveguide 520 may further include a guiding element 530 configured to redirect light 528 propagating within the optical waveguide 520 via TIR to the output coupling element 526. The guiding element 530 may be positioned at a suitable location (or portion) within the optical waveguide 520. For example, the guiding element 530 may be positioned on a first side (surface) 523b-1 of the second solid-state crystal film 523b and may face the output coupling element 526 positioned on a second side (surface) 523a-2 of the first solid-state crystal film 523a. In some embodiments, the guiding element 530 and the output coupling element 526 may have similar structures. The guiding element 530 may include, for example, a 1D diffraction grating or a 2D diffraction grating. The spacing of the diffraction grating may be configured such that the guiding element 530 can guide light 528 propagating within the optical waveguide 520 via TIR toward the output coupling element 526 at a predetermined incident angle. In some embodiments, the guiding element 530 may be referred to as a folded grating. In some implementations, multiple functions, such as the pupil for redirection, folding, and / or expansion of the optical waveguide 520, can be combined in a single diffraction grating, for example, in an output coupling diffraction grating. In some implementations, the aforementioned grating can be divided into more than one segment (or sub-grating) to provide additional functions, such as for tiling the field of view (“FOV”), transmitting monochrome images of different colors, etc.

[0180] In some embodiments, the disclosed optical devices, such as those having a spatially uniform orientation of the axes of crystal molecules in a solid crystal film, are described. Figures 2A-4C The optical device shown can be used as a phase retarder. (Reference) Figure 2B As an example, to effectively change the phase of transmitted light, linearly polarized light incident on optical device 220 can be aligned substantially along the alignment direction 225 (e.g., the x-axis direction) of the crystal molecules 224 to their polarization axis. Optical device 220, used as a phase retarder, can be selectively or additionally configured to function as a polarization management component in an optical device or optical system. For example, when the phase retarder is configured to provide half-wave birefringence for light in a predetermined wavelength spectrum (e.g., the visible spectrum), linearly polarized input light having a first polarization direction can be converted into linearly polarized output light having a second polarization direction perpendicular to the first polarization direction, or circularly polarized input light can be converted into circularly polarized output light with opposite polarization. When the phase retarder is configured to provide quarter-wave birefringence for light in a predetermined wavelength spectrum (e.g., the visible spectrum), linearly polarized input light can be converted into circularly polarized output light, or vice versa.

[0181] Figures 6A-6CThe illustration shows a 3D schematic diagram of the spatially varying orientation of the axes of crystal molecules in a corresponding solid crystal film according to various embodiments. When the orientation of the axes of crystal molecules varies in space, the orientation of the axes of the solid crystal can also vary spatially within the solid crystal film. Figures 6A-6C The solid crystal films and alignment structures shown can have structures or components that can be combined with those described above (e.g., in conjunction with the above). Figure 1A The optical devices 100 shown herein have the same or similar structures or components as those described. Figures 6A-6C The description of the solid crystal film and alignment structure included in the illustrated implementation can be referenced from the above description (including, for example, the combination of...). Figure 1A The implementation scheme shown is described below.

[0182] like Figure 6A As shown, the optical device 600 may include a solid crystal 601 (which may be in the form of a layer, film, or plate). For the purposes of discussion, the solid crystal 601 may be referred to as a solid crystal film 601. The solid crystal film 601 may be disposed on an alignment structure 610. In some embodiments, the solid crystal film 601 may be formed on the alignment structure 610 by a suitable crystal growth process. For illustrative purposes, the alignment structure 610 is shown as a thin layer. The alignment structure 610 may define or include an alignment structure pattern for aligning at least partially the crystal molecules of the solid crystal film 601.

[0183] The solid crystal film 601 may include more than one crystal molecule. The crystal molecules are disposed in layers on the alignment structure 610. For example, Figure 6A The illustrated embodiment shows six layers of crystal molecules. For illustrative purposes, only the first layer of crystal molecules 603a-603d (also referred to as the first more than one crystal molecule 603), the second layer of crystal molecules 604a-604d (also referred to as the second more than one crystal molecule 604), and the third layer of crystal molecules 605a-605d (also referred to as the third more than one crystal molecule 605) are labeled.

[0184] A first crystal molecule 603 may contact the alignment structure 610. A second crystal molecule 604 and a third crystal molecule 605 may be disposed or stacked above or on the first crystal molecule 603, and may not contact the alignment structure 610. The alignment structure 610 may at least partially align the crystal molecules contained in the solid crystal film 601. For example, the first crystal molecule 603 in contact with the alignment structure 610 may be aligned with an alignment structure pattern provided by the alignment structure 610.

[0185] like Figure 6AAs shown, more than one crystal molecule 603a-603d may not be aligned in the same direction or orientation. In other words, the orientation of the crystal molecule's axis varies in space. The reference numerals 602a-602d indicate the axis of the crystal molecule (along which the refractive index can be maximum). Figure 6A As shown, the axes 602a-602d of the first more than one crystal molecule 603a-603d may not be aligned in the same direction or orientation. Crystal molecules in each layer along the z-axis (e.g., the first more than one crystal molecule 603) may have spatially varying orientations and / or alignments in a plane (e.g., the xy plane) parallel to the surface (e.g., the top surface) of the alignment structure (e.g., crystal molecule 604). This pattern may be at least partially defined by the alignment structure pattern of the alignment structure 610. As a result, the orientation of the axes of the solid crystal can also vary spatially within the solid crystal 601.

[0186] In each layer of crystal molecules in the xy plane, the orientation of the crystal molecule's axis can be rotated by a predetermined rotation angle relative to the orientation of the axis of adjacent crystal molecules. For example, each of the first more than one crystal molecule 603a-603d can rotate its corresponding axis by a predetermined rotation angle relative to the orientation of adjacent crystal molecules in the same layer (i.e., in the same xy plane). For example, the orientation of axis 602b of crystal molecule 603b can be rotated by a first predetermined rotation angle relative to the orientation of axis 602a of crystal molecule 603a. The orientation of axis 602c of crystal molecule 603c can be rotated by a second predetermined rotation angle relative to the orientation of axis 602b of crystal molecule 603b. The orientation of axis 602d of crystal molecule 603d can be rotated by a third predetermined rotation angle relative to the orientation of axis 602c of crystal molecule 603c. The first, second, and third predetermined rotation angles can be the same or different. In some embodiments, the first, second, and third predetermined rotation angles can be the same. In some implementations, at least two of the first predetermined rotation angle, the second predetermined rotation angle, and the third predetermined rotation angle may be different.

[0187] The first or more crystal molecules 603 in contact with the alignment structure 610 can be aligned with the alignment pattern of the alignment structure 610. The second or more crystal molecules 604 and the third or more crystal molecules 605 (and other crystal molecules in the layers) can follow the same alignment pattern as the first or more crystal molecules 603, or they can not follow the same alignment pattern as the first or more crystal molecules 603. Figure 6AIn the illustrated embodiment, the second and more than one crystal molecule 604 and the third and more than one crystal molecule 605 (and other crystal molecules in the other layers) follow the same alignment pattern as the first and more than one crystal molecule 603. That is, the orientation of the axes of the crystal molecules disposed on or stacked on the first and more than one crystal molecule 603 follows the same orientation as the axes of the first and more than one crystal molecule 603. In other words, in each layer of crystal molecules disposed on the first and more than one crystal molecule 603, the orientation of the axis of each crystal molecule is the same as the orientation of the axis of the corresponding crystal molecule in the lower layer. For example, the orientation of the axis of crystal molecule 604b is the same as the orientation of the axis of crystal molecule 603b, and the orientation of the axis of crystal molecule 605b is the same as the orientation of the axis of crystal molecule 604b, and so on. Figure 6A As shown, the orientation of axis 607a of crystal molecule 605a in the third layer is the same as the orientation of axis 602a of crystal molecule 603a in the first layer. Crystal molecules 603a and 605a are in the same column along the z-axis.

[0188] like Figure 6B As shown, the optical device 620 may include a solid crystal film 621 and an alignment structure 624. The solid crystal film 621 may be disposed on the alignment structure 624. In some embodiments, the solid crystal film 621 may be a cholesteric crystal film. In some embodiments, the solid crystal film 621 may include chiral crystal molecules or crystal molecules doped with chiral dopants, and the optical device 620 may exhibit chirality, i.e., orientation.

[0189] The solid crystal film 621 may include more than one first crystal molecule 623 and more than one second (i.e., remaining) crystal molecule 625 stacked or disposed on the first more than one crystal molecule 623. The first more than one crystal molecule 623 may be in contact with the alignment structure 624, while the remaining (i.e., the second more than one) crystal molecules 625 may not be in contact with the alignment structure 624. The crystal molecules 623 in contact with the alignment structure 624 may be uniformly aligned in space within the surface of the alignment structure 624 (e.g., the top surface in the xy plane). The second more than one crystal molecule 625 may be stacked in a twisted helical structure in a direction perpendicular to the surface of the alignment structure 624 (e.g., the z-axis direction). Figure 6B In the accompanying drawings, reference numerals 622a-622h indicate the orientation of the crystal molecules' axes in each layer. Figure 6B In the illustrated embodiment, the orientation of the crystal molecules' axes is the same in each layer (e.g., spatially uniform within the layer). Figure 6BAs shown, the orientation of the axes 622a of the crystal molecules 623 in contact with the alignment structure 624 can be spatially uniform. That is, the axes 622a of the first and more than one crystal molecule 623 are aligned in the same direction or orientation. The orientation of the axes of the second and more than one crystal molecule 625 disposed on the first and more than one crystal molecule 623 can have a helical twist in a direction perpendicular to the surface of the alignment structure 624 (e.g., the z-axis direction). Figure 6B As shown, the orientation of each axis 622b-622h can be rotated by a predetermined rotation angle relative to the orientation of the axis in the lower layer. The predetermined rotation angle between two adjacent layers in the z-axis direction can be the same or different (or at least two rotation angles can be different). In some embodiments, the twisted helical structure or the helical twist orientation (e.g., the rotation direction of the axis of the crystal molecule) can be determined by the type of chiral crystal molecule or chiral dopant. The spacing of the twisted helical structure or helical twist can be determined by the helical twisting force of the chiral crystal molecule or the helical twisting force and concentration of the chiral dopant.

[0190] For the purpose of explanation, Figure 6B A cholesteric phase crystal membrane 621 is shown. In some embodiments, more than one cholesteric phase crystal membrane may be stacked one on top of another or side by side, wherein adjacent cholesteric phase crystal membranes may be separated from each other by an alignment structure disposed between two adjacent cholesteric phase crystal membranes. The orientation of the axes of the crystal molecules in the respective cholesteric phase crystal membranes may have a helical twist in a direction perpendicular to the surface of the alignment structure (e.g., the z-axis direction), with a portion of the crystal molecules aligned along the alignment structure. In some embodiments, the helical twists in adjacent cholesteric phase crystal membranes may have opposite helical orientations. In some embodiments, the helical twists in adjacent cholesteric phase crystal membranes may have the same helical orientation.

[0191] Figure 6C The illustration shows a 3D schematic diagram of an optical device 640, which comprises a stack of multiple solid crystal films 641a-641h separated by corresponding alignment structures 644a-644h. Figure 6C As shown, the orientation of the crystal molecules' axes in solid crystal films 641a-641h can be rotated (e.g., gradually rotated) from one solid crystal film to another along a direction perpendicular to the surface of the alignment structure (or the surface of a substrate that may include stacked optical devices 640). In some embodiments, the optical device 640 can be used as an optical rotator.

[0192] In the first solid crystal film 641a, the axes 642a of the crystal molecules 643a in contact with the first alignment structure 644a can be oriented substantially in the xy plane along a first direction or orientation 645a, and the axes of other crystal molecules disposed on the crystal molecules 643a in the first solid crystal film 641a can substantially follow the first orientation 645a. That is, the orientation of the axes of the crystal molecules in the first solid crystal film 641a can be spatially uniform. As a result, the orientation of the axes of the solid crystal 641a can be spatially invariant (e.g., constant). In the second solid crystal film 641b, the axes 642b of the crystal molecules 643b in contact with the second alignment structure 644b can be oriented substantially in the xy plane along a second direction or orientation 645b, and the axes of other crystal molecules disposed on the crystal molecules 643b in the second solid crystal film 641b can substantially follow the same second orientation 645b. The second direction or orientation 645b can be the same as or different from the first direction or orientation 645a. For example, in some embodiments, the second direction or orientation 645b may be rotated by approximately 15° relative to the first direction or orientation 645a. The orientation of the axes of the crystal molecules in the remaining solid crystal films 641c-641h may be determined by the alignment structures 644a-644h, respectively. The orientation of the axes of the crystal molecules in the remaining solid crystal films 641c-641h may be rotated (e.g., gradually) from one solid crystal film to another along a direction perpendicular to the surface of the first alignment structure 644a (or the surface of the substrate on which the stack may be disposed) (e.g., the z-axis direction). Each of the alignment structures 644a-644h in the stack can reset or realign the orientation of the crystal molecules disposed thereon in the corresponding solid crystal film 641a-641h, which can effectively rotate the axis of the solid crystal film 641a-641h along the z-axis direction.

[0193] PBP optical elements can have spatially varying optical axes in a plane perpendicular to the direction of beam propagation. Such a plane can also be referred to as a transverse plane or an in-plane plane. LC has been used to fabricate PBP optical elements by means of a spatially varying LC director in the transverse plane. The optical properties of LC-based PBP optical elements can depend on the refractive index and / or birefringence of the LC. For example, the angular bandwidth and diffraction bandwidth of a polarization-selective grating can increase with increasing birefringence of the LC. Currently available LCs can have refractive indices up to about 1.97 and birefringences up to about 0.3. PBP optical elements based on materials with higher refractive indices and larger birefringences are highly desirable for reducing size and weight while enhancing optical properties. This disclosure provides PBP optical elements based on the disclosed solid crystal, which has a spatially varying orientation of its axis in the transverse plane. That is, the orientation of the solid crystal's axis can be configured to vary spatially within the transverse plane, thereby forming a solid crystal-based PBP optical element. In some embodiments, PBP optical elements fabricated based on solid crystals can have a thickness of about 500 nm to about 5 μm.

[0194] The orientation of the axes of a solid crystal in a transverse plane can be referred to as the in-plane orientation of the solid crystal axes. In some embodiments, the spatially varying in-plane orientation of the solid crystal axes can be achieved by configuring the spatially varying in-plane orientation of the axes of the crystal molecules contained in the solid crystal. In some embodiments, the in-plane orientation of the axes of the crystal molecules contained in the solid crystal can be configured by aligning the crystal molecules with a predetermined in-plane alignment pattern. In some embodiments, the predetermined in-plane alignment pattern of the crystal molecules can be provided by an alignment structure on which a solid crystal is configured (e.g., grown), as described above.

[0195] Figure 7A The illustration shows a transmissive PBP optical element or device 700 according to some embodiments, which may include the disclosed solid crystal or solid crystal film 701. The solid crystal (or solid crystal film) 701 may be any embodiment of the solid crystal described above and herein. In some embodiments, the PBP optical device 700 may also include one or more alignment structures that, in Figure 7A Not shown in the diagram. In some embodiments, the PBP optics 700 may include one or more substrates, which are located in... Figure 7A Not shown in the figure. Based on the in-plane alignment pattern of the crystal molecules in the solid crystal film 701 (or the in-plane orientation of the crystal molecule axes), the PBP optical device 700 can operate as a transmission-type PBP optical device to provide one or more optical functions, such as as a prism, lens, beam refractor, lens array, prism array or a combination thereof.

[0196] Figure 7B The schematic diagram illustrates, according to some implementation schemes, when Figure 7A The image shows an xy-section view of a portion of the orientation 720 of the crystal molecule 703 when the PBP optical device 700 is used as a PBP grating 700. (Example:) Figure 7A and Figure 7B As shown, the PBP grating 700 may include an alignment structure 704 configured to at least partially align the crystal molecules 703 in the solid crystal film 701. For example, crystal molecules 703 in contact with the alignment structure 704 can be aligned by the alignment structure 704, and the remaining crystal molecules 703 in the solid crystal film 701 can follow the alignment of adjacent crystal molecules 703 that have already been aligned. The crystal molecules 703 in the solid crystal film 701 can be periodically and linearly aligned along one or two in-plane directions, such that the orientation of the axes of the crystal molecules 703 in the solid crystal film 701 can vary periodically and linearly along one or two in-plane directions.

[0197] For the purpose of explanation, Figure 7B It shows that the orientation of the axis of crystal molecule 703 can be along an in-plane direction (e.g., Figure 7B The x-axis direction of the crystal molecule 703 varies periodically and linearly. The in-plane orientation of the axial direction of the crystal molecule 703 can vary along the x-axis direction in a linear repeating pattern with a uniform spacing Λ. The spacing Λ of the PBP grating 700 can be half the distance along the x-axis between repeating portions of the pattern. The spacing Λ can partially determine the optical properties of the PBP grating 700. For example, circularly polarized light incident along the optical axis (e.g., the z-axis) of the PBP grating 700 can have a grating output, which includes primary light, conjugate light, and leakage light corresponding to diffraction orders m = +1, -1, and 0, respectively. The spacing Λ can determine the diffraction angle of diffracted light of different diffraction orders. In some embodiments, the diffraction angle of light of a given wavelength can increase as the spacing Λ decreases.

[0198] In some implementations, the PBP grating 700 may be a passive PBP grating having two optical states, a positive state and a negative state (or may operate in both optical states, a positive state and a negative state). The optical state of the PBP grating 700 may depend on the rotation of the circularly polarized input light and the rotation of the crystal molecules in the PBP grating 700. Figure 7C and Figure 7D The diagrams schematically illustrate the positive and negative states of the PBP grating 700 according to some embodiments. In some embodiments, such as Figure 7CAs shown, the PBP grating 700 can operate in a positive state in response to right-hand circularly polarized (“RHCP”) input light 705, and can diffract the RHCP input light 705 of a specific wavelength to a positive angle (e.g., +θ). Figure 7D As shown, the PBP grating 700 can operate in a negative state in response to a left-handed circularly polarized (“LHCP”) light input 707, and can diffract a specific wavelength of LHCP input light 707 to a negative angle (e.g., -θ). Furthermore, in addition to the diffracted light, the PBP grating 700 can also reverse the directionality of circularly polarized light transmitted through it. For example, in… Figure 7C In the configuration shown, the RHCP input light 705 can be converted into the LHCP output light 706 after passing through the PBP grating 700. Figure 7D In the illustrated configuration, the LHCP input light 707 can be converted into RHCP output light 708 after passing through the PBP grating 700. In some embodiments, the PBP grating 700 can operate in response to the LHCP input light being in a positive state and can operate in response to the RHCP input light being in a negative state. For unpolarized input light of a specific wavelength, the PBP grating 700 can diffract the RHCP and LHCP components of the unpolarized input light by positive angles (e.g., +θ) and negative angles (e.g., -θ), respectively. Therefore, the PBP grating 700 can be used as a circularly polarized beam splitter.

[0199] In some embodiments, the PBP grating 700 can switch between positive and negative states when the directionality of the circularly polarized input light is switched by another optical device. For example, an active polarization switch can be coupled to the PBP grating 700. The PBP grating 700 can receive light output from the active polarization switch. The active polarization switch can control (e.g., switch) the directionality of the circularly polarized light incident on the PBP grating 700, thereby controlling the optical state of the PBP grating 700. Depending on the operating state of the active polarization switch (e.g., non-switching or switched state), the active polarization switch can maintain or reverse the directionality of the circularly polarized light. The switching speed of the active polarization switch can determine the switching speed of the PBP grating 700. In some embodiments, the active polarization switch may include a switchable half-wave plate (“SHWP”).

[0200] In some embodiments, the PBP grating 700 can operate in a neutral state when the solid crystal (or solid crystal film) 701 in the PBP grating 700 is configured to be in an amorphous state. In the neutral state, the PBP grating 700 may not diffract the input light and may or may not affect the polarization of the light transmitted through the PBP grating 700. In some embodiments, the PBP grating 700 can switch between a positive / negative state and a neutral state by switching the solid crystal 701 between an aligned crystalline state and an amorphous state. In some embodiments, the solid crystal 701 can switch between an aligned crystalline state and an amorphous state by various methods, such as polarization-based switching, thermal-based switching, or external field-based switching. In some embodiments, the PBP grating 700 can be used as an active PBP grating that can switch between a positive / negative state and a neutral state.

[0201] Figure 8A The schematic diagram illustrates, according to some implementation schemes, when Figure 7A The XY cross-sectional view of a portion of the orientation 820 of the crystal molecule 803 when the PBP optical device 700 is used as a PBP lens 700. Figure 8B The diagram illustrates the implementation schemes in... Figure 8A The diagram shows a cross-section along the x-axis of a portion of the orientation 820 of crystal molecules 803 in the PBP lens 700. For simplicity, each crystal molecule 803 contained in the solid crystal film 701 is represented by... Figure 8A The small bars in the diagram represent molecules, each depicted as having a longitudinal direction (or length direction) and a transverse direction (or width direction). That is, each molecule 803 is depicted as having a longitudinal direction (or length direction) and a transverse direction (or width direction), and the axis of molecule 803 is assumed to be along the assumed axis of the highest refractive index of molecule 803 in the longitudinal direction. The longitudinal direction (or length direction) and transverse direction (or width direction) of the small bars can correspond to the longitudinal direction (or length direction) and transverse direction (or width direction) of molecule 803, respectively.

[0202] like Figure 7A and Figure 8AAs shown, the PBP lens 700 may include an alignment structure 804 configured to at least partially align the crystal molecules 803 contained in the solid crystal film 701. For example, crystal molecules 803 in contact with the alignment structure 804 can be aligned by the alignment structure 804, and the remaining crystal molecules 803 contained in the solid crystal film 701 (e.g., those crystal molecules disposed on the crystal molecules in contact with the alignment structure 804) can follow the alignment of the adjacent crystal molecules 803 that have already been aligned. The orientation of the axes of the crystal molecules 803 contained in the solid crystal film 701 can vary periodically along an in-plane radial direction (e.g., a radial direction).

[0203] The PBP lens 700 can generate a lens profile based on the in-plane orientation of the crystal molecule 803's axis, where the phase difference can be T = 2θ, and θ is the angle between the orientation of the crystal molecule 803's axis and the x-axis direction. (Reference) Figure 8A and Figure 8B The orientation of the axes of crystal molecules 803 can continuously vary from the center (O) 805 to the edge 806 of the PBP lens 700, with a variable spacing Λ. The spacing is defined as the distance between crystal molecules 803, where the orientation of the axes of crystal molecules 803 is rotated approximately 180° from the initial state. The spacing (Λ0) is largest at the center 805 and smallest at the edge 806. r The minimum value is Λ0 > Λ1 > ... > Λ. r In the xy plane, for a PBP lens 700 with a lens radius (r) and a lens focal length (+ / -f), θ can satisfy... Where λ is the wavelength of the incident light. The rotation of the axis of crystal molecule 803 in a continuous plane can be accelerated by moving from the center (0) 805 of PBP lens 700 toward the edge 806, so that the period of the obtained periodic structure (e.g., spacing) can be reduced.

[0204] The PBP lens 700 can be a passive PBP lens 700 with two optical states: a focused state and a defocused state. The optical state of the PBP lens 700 can depend on the rotation of the circularly polarized light incident on the passive PBP lens 700 and the rotation of the crystal molecules in the PBP lens 700. Figure 8C and Figure 8D The diagrams schematically illustrate the focused and defocused states of a PBP lens 700 according to some embodiments. For simplicity, the crystal molecules 803 contained in the solid crystal film 701... Figure 8C and Figure 8D The middle part is represented by a stick. In some implementations, such as Figure 8CAs shown, the PBP lens 700 can operate in a focused state in response to the RHCP input light 809 and can have a positive focal length of 'f'. Figure 8D As shown, the PBP lens 700 can operate in a defocused state in response to the LHCP input light 807 and can have a negative focal length of '-f'. Furthermore, in addition to focusing / defocusing light, the PBP lens 700 can also reverse the directionality of circularly polarized light transmitted through it. For example, in Figure 8C In the configuration shown, the RHCP input light 809 can be converted into LHCP output light 810 after passing through the PBP lens 700. Figure 8D In the configuration shown, the LHCP input light 807 can be converted into RHCP output light 808 after passing through the PBP lens 700. In some embodiments, the PBP lens 700 can operate in response to the LHCP input light being in a defocused state and in response to the RHCP output light being in a focused state.

[0205] Similar to a passive PBP grating, the PBP lens 700 can switch between a focused and defocused state when the directionality of circularly polarized incident light is switched by another optical device. For example, an active polarization switch can be coupled to the PBP lens 700. The PBP lens 700 can receive light output from the active polarization switch. The active polarization switch can control (e.g., switch) the directionality of the circularly polarized light incident on the PBP lens 700, thereby controlling the optical state of the PBP lens 700. Depending on the operating state of the active polarization switch (e.g., non-switching or switched), the active polarization switch can maintain the directionality of the circularly polarized light or reverse the directionality of the circularly polarized light after it has passed through the active polarization switch. The switching speed of the active polarization switch can determine the switching speed of the PBP lens 700. In some embodiments, the active polarization switch may include a SHWP (Switching-Off-Pulse Filter).

[0206] In some embodiments, the PBP lens 700 can operate in a neutral state when the solid crystal (or solid crystal film) 701 in the PBP lens 700 is configured to be in an amorphous state. In the neutral state, the PBP lens 700 may not focus / defocus the input light and may or may not affect the polarization of light transmitted through the PBP lens 700. In some embodiments, the PBP lens 700 can switch between a focused / defocused state and a neutral state by switching the solid crystal 701 between an aligned crystalline state and an amorphous state. In some embodiments, the solid crystal 701 can switch between an aligned crystalline state and an amorphous state by various methods, such as polarization-based switching, thermal-based switching, or external field-based switching. In some embodiments, the PBP lens 700 can be used as an active PBP lens that can switch between a focused / defocused state and a neutral state.

[0207] Apart from Figures 7A-7D and Figures 8A-8D In addition to the transmissive PBP optical elements or devices shown, reflective PBP optical elements or devices can also be implemented based on the disclosed solid crystals. Figure 9A A diagram illustrates a reflective PBP optical element or device 900, which may include a solid crystal or solid crystal film 901. The solid crystal film 901 may be any embodiment of the solid crystal or solid crystal film described above and herein. In some embodiments, the PBP optical device 900 may also include one or more alignment structures that, in Figure 9A Not shown. In some embodiments, the PBP optics 900 may also include one or more substrates, which are in Figure 9A Not shown in the figure. Based on the in-plane alignment pattern of the crystal molecules in the solid crystal film 901 (or the in-plane orientation of the crystal molecule axes), the PBP optical device 900 can operate as a reflective PBP optical device with one or more optical functions.

[0208] Figure 9B A 3D diagram schematically illustrates a portion of the orientation of the axes of crystal molecules 903 (represented by 903a, 903b) contained in a solid crystal film 901 of the optical device 920, and Figure 9C The illustration shows when Figure 9A The xz section diagram of the orientation of the 903 crystal molecule axis 940 when the PBP optics are used as a reflective PBP grating is shown. For discussion purposes, Figure 9BEach molecule 903 in the solid crystal film 901 is depicted as having a longitudinal direction (or length direction) and a transverse direction (or width direction), and the axis of the molecule 903 is assumed to be along the assumed axis of the highest refractive index of the molecule 903 in the longitudinal direction of the molecule 903. To simplify the illustration of the orientation of the axes of the crystal molecules 903 across the entire solid crystal film 901, each crystal molecule 903 contained in the solid crystal film 901 is represented by... Figure 9C The bars in the diagram represent the components, where each bar is depicted as having a longitudinal direction (or length direction) and a transverse direction (or width direction). The longitudinal direction (or length direction) and transverse direction (or width direction) of the bars can correspond to the longitudinal direction (or length direction) and transverse direction (or width direction) of molecule 903, respectively.

[0209] Reflective PBP gratings, due to their physical properties, can also be called reflective polarizer gratings ("PVG"). For example... Figure 9B and Figure 9C As shown, in some embodiments, the solid crystal film 901 may be a cholesteric phase crystal film 901. In some embodiments, the solid crystal film 901 may comprise chiral crystal molecules or crystal molecules doped with chiral dopants, and the solid crystal may exhibit chirality, i.e., directional properties. The axis 906 of the crystal molecule 903a in contact with the alignment structure 904 may be along one of the in-plane directions (e.g., Figure 9B The x-axis in the image varies periodically and linearly. The axis 907 of the crystal molecules 903b stacked above the crystal molecules 903a in contact with the alignment structure 904 can be along a direction perpendicular to the surface of the solid crystal film 901 (e.g., ...). Figure 9B The z-axis direction (e.g., the thickness direction of the solid crystal film 901) is twisted in a helical manner. Such orientation of the axes of the crystal molecules 903, produced by the alignment structure 904, can create a periodic and tilted plane 905 with a constant refractive index within the solid crystal film 901. In other words, crystal molecules 903 from different layers having the same axial orientation can form a tilted periodic plane 905 with a constant refractive index within the solid crystal film 901.

[0210] Unlike a transmission PBP grating that diffracts input light by modulating its phase, a reflection PVG 900 can diffract input light via Bragg reflection (or tilted multilayer reflection). The reflection PVG 900 can primarily diffract circularly polarized light with the same rotatomicity as the spiral structure of the reflection PVG 900, and primarily transmit light with other polarizations without altering the polarization of the transmitted light. For example, when the circularly polarized input light has a rotatomicity opposite to that of the spiral structure of the reflection PVG 900, the input light can be primarily transmitted up to the 0th order, and the polarization of the transmitted light can be substantially preserved (e.g., unaffected). The diffraction efficiency of the reflection PVG 900 can be a function of the thickness of the solid crystal film 901. For example, the diffraction efficiency of the reflection PVG 900 can increase monotonically with thickness and then gradually saturate (e.g., remain substantially constant).

[0211] The optical elements or devices according to the embodiments can be implemented in multiple fields. Such implementations are within this scope. In some embodiments, the disclosed optical elements or devices can be implemented as multifunctional optical components in near-eye displays (“NEDs”) for augmented reality (“AR”), virtual reality (“VR”), and / or mixed reality (“MR”). For example, the disclosed optical elements or devices can be implemented as waveguide-based combiners, eye-tracking components, adjustment components for achieving multifocal or variable focus, display resolution enhancement components, pupil steering elements, and polarization control components (e.g., quarter-wave plates or half-wave plates), which can significantly reduce weight and size and enhance the optical performance of the NED.

[0212] Figure 10A The diagram illustrates NED 1000 according to some implementation schemes. Figure 10B The diagram illustrates some implementation schemes. Figure 10A The diagram shows a top-view cross-sectional view of half of the NED 1000. The NED 1000 may include one or more of the disclosed optical elements or devices, such as waveguides, PBP lenses, PBP gratings, or reflective PVH gratings. Figure 10A As shown, the NED 1000 may include a frame 1005 configured to be worn by a user. The NED 1000 may include a left-eye display system 1010L and a right-eye display system 1010R mounted to the frame 1005. Each of the left-eye display system 1010L and the right-eye display system 1010R may include one or more image display components configured to project computer-generated virtual images onto a left display window 1015L and a right display window 1015R within the user's field of view (FOV). Examples of the left-eye display system 1010L and the right-eye display system 1010R may include a waveguide display system. For illustrative purposes, Figure 10AThe display system shown may include a light source assembly 1035 coupled to (e.g., mounted on) a frame 1005. The NED 1000 can be used as a VR device, AR device, MR device, or a combination thereof. In some embodiments, when the NED 1000 is used as an AR device and / or MR device, the right display window 1015R and the left display window 1015L may be completely transparent or at least partially transparent from the user's perspective, allowing the user to view the surrounding real-world environment. In some embodiments, when the NED 1000 is used as a VR device, the right display window 1015R and the left display window 1015L may be opaque, allowing the user to immerse themselves in the VR image provided by the NED 1000.

[0213] Figure 10B It is based on some implementation plans. Figure 10A The image shows a top view of the cross-section of the NED 1000. (See image.) Figure 10B As shown, display system 1010 (which may represent right-eye display system 1010R or left-eye display system 1010L) can be a waveguide display system, which may include waveguide displays or stacked waveguide displays for one or more of a user's eyes 1020. For example, a stacked waveguide display may be a stacked multicolor display (e.g., a red-green-blue (“RGB”) display) including waveguide displays, whose respective monochromatic light sources can be configured to emit light of different colors. In some embodiments, the waveguide display system may include a light source assembly 1035 configured to generate image light, and an output waveguide 1015 configured to output extended image light to the user's eyes 1020. In some embodiments, output waveguide 1015 may be used as a waveguide-based combiner in NED 1000 to overlay virtual world images and real-world images. The waveguide-based combiner may be used as a display window (e.g., left display window 1015L or right display window 1015R). Output waveguide 1015 may include one or more input coupling elements configured to couple light from a light source assembly into the output waveguide. In some embodiments, output waveguide 1015 may include one or more output coupling (or decoupling) elements configured to couple light out of the output waveguide toward the user's eye 1020. In some embodiments, output waveguide 1015 may include one or more guiding elements configured to guide light output from one or more coupling elements to one or more decoupling elements.

[0214] In some implementations, the NED 1000 may include a variable focus / multifocus block 1040. The display system 1010 and the variable focus / multifocus block 1040 together can provide image light to the exit pupil 1025. The exit pupil 1025 may be the location where the user's eye 1020 is positioned. For illustrative purposes, Figure 10B A cross-sectional view associated with a single eye 1020 is shown. A similar display system separate from the display system 1010 and a similar variable focus / multifocus block separate from the variable focus / multifocus block 1040 can be included in the other half (not shown) of the NED 1000 to direct image light to the user's other eye.

[0215] In some embodiments, the NED 1000 may include an eye-tracking system (not shown). The eye-tracking system may include, for example, one or more light sources configured to illuminate one or both eyes of a user, and one or more cameras configured to capture images of one or both eyes of the user based on light emitted by the light sources and reflected by one or both eyes. In some embodiments, the NED 1000 may include an adaptive dimming element 1045 that can dynamically adjust the transmittance of real-world objects viewed through the NED 1000, thereby switching the NED 1000 between VR and AR devices or between VR and MR devices. In some embodiments, along with switching between AR / MR devices and VR devices, the adaptive dimming element 1045 may be used in AR and / or MR devices to reduce the brightness difference between real and virtual objects.

[0216] In some implementations, the waveguide-based combiner 1015 can be connected via disclosed solid-state crystal film-based optical devices such as... Figure 5A Waveguide 500 or Figure 5B The waveguide 520 in the solid crystal film is used to achieve a spatially uniform orientation of the axes of the crystal molecules within the solid crystal film. In some embodiments, the input coupling element, guiding element, and / or output coupling (or decoupling) element disposed at the waveguide-based combiner 1015 can be implemented by the disclosed solid crystal film-based optics, which have periodicity and linear orientation of the axes of the crystal molecules in the planar direction of the solid crystal film, such as... Figures 7A-7D The PBP grating 700 shown, or Figures 9A-9CThe illustrated reflective PVG grating 900. Compared to various gratings used in conventional NEDs, such as surface relief gratings (“SRG”) and holographic gratings (“HG”), the disclosed optics used as a PBP grating can exhibit high efficiency over a large field of view and a wide wavelength spectrum (e.g., the visible wavelength band), and can offer advantages for waveguide-coupled NEDs used in VR, AR, and / or MR applications. Furthermore, Figures 9A-9C The illustrated reflective PVG grating 900 can be configured to deflect circularly polarized light with a specific optics rotation and transmit circularly polarized light with orthogonal optics rotation. When the reflective PVG grating 900 is used as a combiner in an NED 1000 for AR and / or MR applications to combine displayed images and real-world light, the total transmittance of real-world light can be increased. A waveguide combiner based on a high-refractive-index solid-state crystal can be configured to increase the FOV of the waveguide-based NED and reduce the weight of the display optics by reducing the number of combiner boards to one (or more) for efficient RGB input and output coupling. Input coupling elements, guiding elements, and / or output coupling (or decoupling) elements (e.g., gratings) based on high-refractive-index solid-state crystals can be configured to be compatible with high-refractive-index and high-FOV waveguides used in NEDs.

[0217] also, Figure 10B The variable focus / multifocus block 1040 shown can be configured to adjust the distance of light emitted from the waveguide display system such that the light appears at a predetermined focal length from the user's eye 1020. The variable focus / multifocus block 1040 may include one or more variable focus / multifocus structures arranged in optical series. The variable focus / multifocus structure may be referred to as an optics device configured to dynamically adjust its focus according to instructions from a controller. The variable focus / multifocus structure may include one or more monofocal lenses with fixed optical power and / or one or more variable focus or multifocal lenses with adjustable (or variable) optical power. One or more multifocal lenses may be achieved using the disclosed solid-state crystal-based optics such as... Figures 8A-8D The PBP lens 700 shown is used to achieve this, wherein the solid crystal film has a periodic orientation of the crystal molecule axes in the radial direction within the plane of the solid crystal film.

[0218] The applications of the disclosed optical devices in NEDs mentioned above are for illustrative purposes only. Furthermore, the disclosed solid-state crystal-based optical devices can also be used to realize eye-tracking components, display resolution enhancement components, and pupil steering elements, etc., without being limited by the contents of this disclosure. The disclosed solid-state crystal-based optical devices can be lightweight, thin, compact, and custom-designed. Therefore, by using the disclosed optical devices as multifunctional optical components in NEDs, the weight and size of NEDs can be significantly reduced, while optical performance and appearance can be enhanced, thus opening up possibilities for future smart glasses.

[0219] Furthermore, the solid crystals formed on one or more alignment structures disclosed herein can be implemented in electronic devices to improve their electronic properties. Conventional solid crystals, such as polycyclic aromatic hydrocarbons, have been used as organic semiconductors in a variety of organic electronic devices in the field of flexible electronics, such as field-effect transistors (“FETs”), thin-film transistors (“TFTs”), photovoltaic devices, etc. It has been demonstrated that altering the lattice constant of a conventional solid crystal (e.g., compressing a conventional solid crystal) can enhance charge carrier mobility and thus enhance the electronic transport properties of organic electronic devices. The solid crystals formed (e.g., grown) on one or more alignment structures disclosed herein can be configured to have a controllable amount of strain by adjusting the alignment structures, such that a specific desired lattice can be obtained for the crystal. In some embodiments, strain can vary across the solid crystal; for example, strain can vary in the same device based on the disclosed solid crystal. In some embodiments, strain can vary across multiple solid crystals disposed on the same substrate (e.g., disposed on the same substrate); for example, strain can vary across multiple devices including corresponding solid crystals. In some implementations, strain can vary in a specific spatial pattern (such as a PBP-type pattern), which can contribute to new electron transport properties.

[0220] This disclosure also provides various methods for manufacturing the disclosed solid-state crystal-based optical elements or devices. Such optical elements or devices may include the PBP optical elements or optical waveguides disclosed herein and described above. For example, Figure 11AThis is a flowchart illustrating a method 1100 for manufacturing an optical device. The optical device may include a solid crystal. Method 1100 may include providing an alignment structure (step 1105). Various methods can be used to provide the alignment structure. For example, the alignment structure may be provided on a substrate. In some embodiments, the alignment structure may be formed as a separate element on the surface of the substrate (e.g., deposition, coating). In some embodiments, the alignment structure may be integrally formed on the surface of the substrate or at least partially in the surface of the substrate by a suitable process (e.g., etching). In some embodiments, the alignment structure may be provided without using a substrate. For example, the alignment structure may be a prefabricated structure. The alignment structure may include an alignment structure pattern or define an alignment structure pattern.

[0221] In some embodiments, providing an alignment structure may include at least one of the following: forming a photoalignment layer on the surface of a substrate by photoprocessing a photosensitive material; forming a mechanically rubbed alignment layer on the surface of a substrate; forming an alignment layer with anisotropic nanoimprints on the surface of a substrate; directly forming anisotropic reliefs on the surface of a substrate by wet or dry etching; forming an alignment structure on the surface of a substrate based on ferroelectric or ferromagnetic materials deposited on the surface of the substrate; providing a crystalline layer or crystalline substrate that defines the alignment pattern as the alignment structure; or forming an alignment structure on the surface of a substrate by crystallization in the presence of a magnetic field or electric field.

[0222] Method 1100 may further include forming a solid crystal on an alignment structure comprising crystal molecules aligned in a predetermined alignment pattern, the predetermined alignment pattern being at least partially defined by the alignment structure (step 1110). Various methods can be used to form a solid crystal (or solid crystal film, layer, or plate) on an alignment structure. For example, in some embodiments, the solid crystal may be grown on the alignment structure based on molten solid crystal material. Therefore, forming a solid crystal on an alignment structure can include growing a solid crystal on the alignment structure. In some embodiments, forming a solid crystal on an alignment structure is performed using at least one of the following processes: vapor deposition including at least one of organic crystal molecular bundle epitaxy or hot-wall epitaxy of organic crystal molecules, solvent-assisted deposition via thermal alignment, mold alignment or surface alignment, polymer-assisted continuous casting, physical vapor transport (e.g., Figure 15 As shown), crystal growth processes based on molten crystal materials (such as...) Figure 16 As shown), temperature-assisted zone annealing (e.g.) Figure 17 (as shown) or spin coating.

[0223] Method 1100 may include Figure 11AOther processes not shown. For example, in some embodiments, multiple alignment structures may be provided, and multiple solid crystals (or solid crystal layers) may be formed. The alignment structure may be a first alignment structure, the predetermined alignment pattern may be a first predetermined alignment pattern, the solid crystal may be a first solid crystal, and the crystal molecules may be first crystal molecules. Method 1100 may further include providing a second alignment structure on the first solid crystal and forming a second solid crystal on the second alignment structure. The second solid crystal may include second crystal molecules aligned with a second predetermined alignment pattern, the second predetermined alignment pattern being at least partially defined by the second alignment structure.

[0224] In some embodiments, the solid crystal formed by method 1100 may be optically anisotropic, having a principal refractive index of at least about 1.5 and an optical anisotropy of at least about 0.1 (e.g., birefringence). The principal refractive index of the solid crystal may be the refractive index in a direction parallel to the axis of the solid crystal. The axis of the solid crystal may be the axis along which the solid crystal has the highest refractive index.

[0225] Figure 11B This is a flowchart illustrating a method 1130 for manufacturing an optical device, which may include a solid crystal. Method 1130 may include providing molten crystal material and an alignment structure in contact with each other (step 1135). Various methods can be used to provide the molten crystal material and alignment structure in contact with each other. In some embodiments, the molten crystal material may be coated onto the alignment structure. In some embodiments, the molten crystal material may be deposited onto the alignment structure. In some embodiments, the molten crystal material may be introduced into a container, and the alignment structure may be disposed on at least one wall of the container (e.g., a bottom wall, a side wall). In some embodiments, the alignment structure may be immersed in or inserted into the molten crystal material.

[0226] Method 1130 may further include generating a solid crystal based on a molten crystalline material, wherein the solid crystal comprises crystal molecules aligned with a predetermined alignment pattern, the predetermined alignment pattern being at least partially defined by an alignment structure (step 1140). Various methods disclosed herein can be used to generate solid crystals based on molten crystalline materials.

[0227] Method 1130 may include Figure 11BOther processes not shown. For example, in some embodiments, generating a solid crystal includes cooling a molten crystal material. In some embodiments, generating a solid crystal may include growing a solid crystal based on a molten crystal material by pulling a seed crystal away from a die. The die may include at least one capillary that is at least partially configured to allow molten crystal material to flow through it during the growth of the solid crystal. The die may also include a surface having a predetermined shape and an alignment structure. Depending on the alignment structure, the solid crystal may grow along the surface of the die.

[0228] Figure 11C This is a flowchart illustrating method 1150 for manufacturing an optical device, which may include a solid crystal. Method 1150 may include moving molten crystal material in a space between two substrates while maintaining contact between the molten crystal material and two opposing surfaces of the two substrates, wherein each of the two opposing surfaces includes an alignment structure in contact with the molten crystal material (step 1155). Moving the molten crystal material can be achieved using various transport or movement mechanisms. For example, in some embodiments, mechanical mechanisms such as conveyor belts or robotic arms may be used to move the molten crystal material along the two substrates while maintaining contact between the molten crystal material and the two mutually facing surfaces of the two substrates. For the molten crystal material, a thermal gradient may be maintained by suitable temperature control devices (e.g., heating devices and / or controllers). Method 1150 may also include growing a solid crystal from the molten crystal material using seed crystals, the solid crystal comprising crystal molecules aligned in a predetermined alignment pattern defined at least partially by alignment structures (step 1160). Method 1150 may also include other additional or alternative steps, such as processing (e.g., by heating) the solid crystal material to produce the molten crystal material. In some implementations, the growth of solid crystals can be achieved by other suitable methods. For example, the growth of solid crystals can be achieved by vapor growth from organic materials, resulting in epitaxial growth of vapor over the alignment structure. This method can also be applied to cholesteric (or distorted) phase growth.

[0229] Figure 11DThis is a flowchart illustrating method 1170 for manufacturing an optical device, which may include a solid crystal. Method 1170 may include processing a solid crystal material in a crucible to produce a molten crystal material (step 1175). Various suitable methods can be used to produce the molten crystal material. For example, the solid crystal material may be heated by a heating device to produce the molten crystal material. In some embodiments, the solid crystal material may be subjected to microwaves or high pressure to produce the molten crystal material. Method 1170 may also include guiding the molten crystal material through one or more capillaries of a die onto a surface including at least one alignment structure (step 1180). Method 1170 may also include growing a solid crystal from the molten crystal material using seed crystals, the solid crystal comprising crystal molecules aligned in a predetermined alignment pattern defined at least partially by at least one alignment structure (step 1185).

[0230] In some embodiments, the surface of the die can have a predetermined curved shape, and the grown solid crystal can have a substantially the same curved shape as the die surface. In other words, curved solid crystals and / or curved optical devices can be fabricated.

[0231] In some embodiments, growing a solid crystal may include pulling a seed crystal disposed at the top portion of a die away from the die to allow the solid crystal to grow along the surface of the die at the meniscus-crystal interface. The disclosed method may also include removing the grown solid crystal from the crucible. The disclosed method may further include cooling the solid crystal removed from the crucible.

[0232] Figures 12A to 12C The illustration shows a process for manufacturing optical devices including solid-state crystals according to some embodiments. For example... Figure 12A As shown, a substrate 1201 can be provided. (As indicated...) Figure 12B As shown, the alignment structure 1202 can be disposed on the surface of the substrate 1201 (e.g., disposed on the surface of the substrate 1201). In some embodiments, the alignment structure 1202 can be formed as a separate element on the substrate 1201. In some embodiments, the alignment structure 1202 can be formed as an integral part of the substrate 1201. For example, the alignment structure 1202 can be etched on the surface of the substrate 1201 or at least partially etched in the surface of the substrate 1201. In some embodiments, it can be omitted. Figure 12A The process shown can provide a prefabricated alignment structure 1202 directly without a substrate.

[0233] like Figure 12CAs shown, solid (or molten) crystal molecules 1203 can be disposed (e.g., deposited, coated, formed, grown, etc.) on the alignment structure 1202. In some embodiments, the solid crystal molecules 1203 can be grown on the alignment structure 1202 based on molten crystal material. In some embodiments, Figure 12C The process can be performed in a crucible containing molten crystal material. In some embodiments, an alignment structure can be provided at the die. The alignment structure 1202 can include an alignment structure pattern or define an alignment structure pattern. The alignment structure 1202 can align crystal molecules 1203 at least partially with a predetermined alignment pattern. The alignment structure pattern may be the same as or different from the predetermined alignment pattern. In some embodiments, a first or more crystal molecules in contact with the alignment structure 1202 can be aligned with the alignment structure pattern. Other crystal molecules arranged (e.g., coating, growth, etc.) on the first or more crystal molecules can follow the alignment and / or orientation of the first or more crystal molecules. In some embodiments, other crystal molecules disposed on the first or more crystal molecules can be twisted or rotated relative to the corresponding first or more crystal molecules. In some embodiments, crystal molecules 1203 can be uniformly aligned. In some embodiments, crystal molecules 1203 can be non-uniformly aligned. For example, the orientation of the axes of crystal molecules 1203 may not be in the same orientation or direction. Conversely, the orientation of the axes of crystal molecule 1203 can vary in space.

[0234] Figures 13A to 13D The illustration shows a process for manufacturing optical devices including solid-state crystals according to some embodiments. For example... Figure 13A As shown, a substrate 1301 can be provided. (As indicated...) Figure 13B As shown, an alignment structure 1302 can be provided. The alignment structure 1302 may include an alignment structure pattern or define an alignment structure pattern, as indicated by arrow 1303. Figure 13C As shown, crystal molecules can be disposed (e.g., formed, deposited, grown, coated, etc.) onto the alignment structure 1302. A first plurality of crystal molecules 1304 (or a first layer) can be disposed on the alignment structure 1302. The first plurality of crystal molecules 1304 can be aligned by the alignment structure 1302 with an alignment structure pattern. A second plurality of crystal molecules 1306 (or a second layer) can be disposed on the first plurality of crystal molecules 1304. The second plurality of crystal molecules 1306 may or may not follow the same alignment pattern as the first plurality of crystal molecules 1304. In some embodiments, the second plurality of crystal molecules 1306 may follow the same alignment pattern as the first plurality of crystal molecules 1304, such as... Figure 13CAs shown. In some embodiments, the second or more crystal molecules 1306 may have a twist (or rotation) relative to the corresponding first or more crystal molecules 1304. Figure 13D As shown, a third or more crystal molecule 1308 may be disposed on the second or more crystal molecule 1304. The third or more crystal molecule 1308 may or may not follow the same alignment pattern as the second or more crystal molecule 1306. Additional layers of crystal molecules may be formed on the third or more crystal molecule 1308. In some embodiments, one or more additional alignment structures may be disposed between different layers of crystal molecules.

[0235] In some implementations, vapor deposition methods can be used to fabricate solid crystals. For example, vapor deposition of organic crystal molecules can include one or more of organic molecular beam epitaxy and hot-wall epitaxy. The surface of the substrate can be modified to control molecular orientation, and thus crystal orientation. For example, alignment structures can be formed on the surface of the substrate to define patterns for aligning crystal molecules. Hexagonal boron nitride can be coated using chemical vapor deposition (“CVD”) to produce van der Waals surfaces, thereby allowing for independent thin films of organic solid crystals. Organic molecular beam epitaxy can use ultra-high vacuum conditions. Hot-wall epitaxy can use high vacuum conditions, such as about 10 -6 millibar.

[0236] In some embodiments, solid crystals can be fabricated using solvent-assisted (or solvent-assisted) deposition methods. For organic crystallization, this method can be combined with thermal / mold / surface alignment to obtain large-size crystals with high purity. For example, solid crystals can be formed based on a temperature / solvent-assisted single-crystal formation process. In such a process, organic molecules can be dissolved in a solvent. The substrate can be placed in the solution at a uniformly controlled temperature. Recrystallization can be performed on a locally cooled substrate. Oxidized silicon and thermocouples can be used to control the temperature. In some embodiments, solid crystals can be formed based on a mold / temperature-assisted crystallization process. In this process, organic molecules can self-assemble in a confined space at high temperatures during a drying process. This process can use a silicon oxide surface with a trichloro(octadecyl)silane polyurethane acrylate mold. In some embodiments, solid crystals can be formed based on a polymer-assisted continuous casting process via a doctor blade coating process. The polymer can be used to increase the viscosity of the organic molecule solution to prevent film slippage. A moving stage with a speed-controlled doctor blade can be used. In some embodiments, solid crystals can be formed based on a surface alignment / solvent-assisted patterning process. The surface of the substrate can be patterned to induce molecular alignment. Vaporized solvents can be used to transfer molecules toward a configuration with a lower energy state. Controlled exchange / removal of solvents can be performed to solidify molecules.

[0237] In some implementations, solid crystals can be formed based on zone annealing methods. For example, a temperature-assisted crystallization process can be used. Utilizing high temperatures above the melting temperature can generate a sharp temperature gradient. The direction and / or purity of the crystals can be controlled via the speed at which an organic thin film (which may be coated on a substrate) moves across the thermal gradient. A moving stage with a sharp thermal gradient can be used in this process.

[0238] Figure 14 A system 1400 for manufacturing an optical device, which may include a solid crystal, is schematically illustrated according to some embodiments. System 1400 can be configured to grow a solid crystal based on a molten crystal material. System 1400 may include a crucible 1405. The solid crystal material can be placed in the crucible 1405 and can be processed (e.g., heated) to produce a molten crystal material 1410. Figure 14 Devices (e.g., heating elements) for raising the temperature of the solid crystal material or crucible 1405 and controllers for controlling the heating elements are not shown. A die 1415 may be disposed in the crucible 1405. The die 1415 may include more than one capillary for guiding the flow of the molten crystal material 1410. For example, the die 1415 may include a central capillary 1431 and an annular capillary 1432. The die 1415 may include a surface 1420. The surface 1420 may include an alignment structure (not labeled) deposited or formed on or at least partially deposited or formed in the surface 1420. The alignment structure may define or include an alignment structure pattern. The alignment structure may be configured such that crystal molecules grown on the alignment structure are at least partially aligned with a predetermined alignment pattern. A seed crystal 1435 may be disposed on the die 1415. Seed crystal 1435 can be pulled away or removed from die 1415, allowing molten crystal material 1410 to follow the movement of seed crystal 1435. A meniscus can be formed at the interface between molten crystal material 1410 and seed crystal 1435. At the meniscus-crystal interface, solid crystal 1440 can grow. Molten crystal material 1410 can flow to surface 1420 of die 1415 via central capillary 1431 and annular capillary 1432. Solid crystal can grow on surface 1420 and can be at least partially aligned to a predetermined alignment pattern by an alignment structure provided at surface 1420. Solid crystal 1440 can be of any suitable shape, depending on the shape of surface 1420 of die 1415. For example, surface 1420 can be a flat surface, and solid crystal 1440 can include a flat shape.

[0239] Figure 15The illustration depicts a method for fabricating organic crystals using physical vapor transport (also known as physical vapor deposition) according to some embodiments. Physical vapor transport is a vacuum deposition method for producing thin films by changing a material in a condensed phase to a gas phase and transporting the gas-phase material to form a thin film in the condensed phase. Examples of physical vapor transport include sputtering and evaporation. This method involves evaporating condensed source material and transporting the vapor onto a target substrate to form a condensed thin film. The method is carried out under controlled conditions (e.g., a chamber such as a vacuum chamber). Figure 15 As shown in Part I, source material 1504 (e.g., organic material) is positioned in a first end region of chamber 1500. Source material 1504 is evaporated (e.g., by heating) to release evaporated molecules and / or particles (e.g., evaporated molecules 1506). Evaporated molecules 1506 are transported within chamber 1500 to a substrate (e.g., substrate 1502) and condensed to form (e.g., grow) organic crystals on the surface of substrate 1502. Figure 15 Part III shows organic crystals 1512 on surface 1502-1 of substrate 1502. In some embodiments, organic crystals 1512 correspond to those described above. Figure 1A The solid crystal 115 is described.

[0240] In some embodiments, growing organic solid crystals involves physical vapor transport onto a flat or curved substrate (e.g., substrate 1502) having surfaces configured to contact the organic solid crystal (e.g., organic solid crystal molecule 1506) (e.g., surface 1502-1, such as a controlled nucleation surface). In some embodiments, Figure 15 The substrate 1502 in the text corresponds to the above regarding Figure 1A The substrate 105 is described. In some embodiments, surface 1502-1 includes or corresponds to the following regarding... Figure 1AThe alignment structure 110 is described. For example, the alignment layer can be used to control the orientation of organic solid crystal molecules, thereby controlling crystal orientation (e.g., the controlled nucleation surface is the surface of the alignment layer). In some embodiments, the alignment layer (or a portion thereof, such as a contact surface) is primarily made of a crystalline fluoropolymer (e.g., PTFE, PDVF). The fluoropolymer can be formed with long chains having substantially parallel to one of the in-plane directions or perpendicular to the in-plane directions. In some embodiments, the alignment layer (or a portion thereof, such as a contact surface) is primarily made of a polyolefin polymer (e.g., PE). The polyolefin polymer can be formed with long chains having substantially parallel to one of the in-plane directions or perpendicular to the in-plane directions. In some embodiments, the first surface is primarily made of a liquid crystal polymer having a nematic phase, which allows the liquid crystal polymer molecules to align in a pre-designed direction. In some embodiments, the first surface is primarily made of an alignment layer (e.g., a photoalignment layer, a polyimide with uniaxial friction). In some embodiments, the first surface is primarily made of an amorphous polymer with low surface energy (e.g., organosilicon, siloxane) to form a controlled nucleation surface. The molecular orientation of the organic solid crystal is controlled by surface energy matching. In some embodiments, the first surface is primarily made of an amorphous inorganic material (e.g., SiO2). Optionally, the inorganic surface is functionalized with alkyl / alkoxysilanes. In some embodiments, the substrate and the first surface are made of the same material, which has been highly oriented by stretching and heating in one direction. Examples include PEN, polyolefins, and polyimides. In some embodiments, the substrate is made of a material different from the first surface. Examples include inorganic amorphous materials such as SiO2, fused silica, quartz, organosilicon, and siloxane. Inorganic crystalline materials, such as silicon, siloxanes, SiC, and sapphire; and organic materials, such as polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups (e.g., polytetrafluoroethylene, Teflon, PFA, polyethylene naphthalate, polystyrene, and polyolefins). In some embodiments, the controlled nucleation surface includes a non-polymer controlled nucleation surface comprising one or more organic structures selected from the group consisting of organic structures of formulas 6-1 to 6-5 described above.

[0241] In some embodiments, the growth of organic solid crystals further includes the use of non-reactive gases, such as non-solvent vapors (e.g., inert gases) and / or solvent vapors. For example, as... Figure 15As shown in Part II, evaporated organic molecules 1506 are transported from source material 1504 toward substrate 1502 with the aid of transport vapor. In some embodiments, transport vapor 1508 is a combination of non-solvent vapor (e.g., inert gas) or solvent vapor. In some embodiments, transport vapor 1508 comprises either non-solvent vapor or solvent vapor. Controlling the type and percentage of non-solvent vapor allows control of the concentration of organic solid crystal vapor, flow rate, and solidification kinetics, thereby controlling nucleation and crystal growth rates. Solvent vapor is used to selectively dissolve and remove defects, such as boundaries between amorphous or polycrystalline domains. In embodiments where solvent vapor is used for organic crystal growth, the solvent vapor is removed (e.g., evaporated) after the formation of the organic crystal. For example, in Figure 15 In Part III, solvent vapor 1510 evaporates from organic crystal 1512.

[0242] Figure 16 The illustration depicts the fabrication of organic crystals using melt recrystallization according to some embodiments (e.g., Figure 1A The method described in [the text] (115) for growing solid organic crystals. In some embodiments, growing organic solid crystals includes a recrystallization process from a molten state, wherein ampoules with designed configurations and surface modifications are used. In some embodiments, the ampoules (e.g., ampoule 1602) are positioned within a temperature-controlled chamber 1600, such as... Figure 16 As shown in Part I, chamber 1600 includes two portions (e.g., portion 1610-1 and portion 1610-2) separated by a temperature gate (e.g., gate 1606 including opening 1604). Portion 1610-1 has a melting point higher than that of organic crystals (e.g., T). m The ampoule 1602 can be moved between portions 1610-1 and 1610-2 of the chamber 1600 (e.g., in the direction indicated by arrow 1608) such that the temperature of the organic crystal disposed within the ampoule 1602 can be changed according to the respective temperatures of portions 1610-1 and 1610-2. In particular, moving the ampoule 1602 containing the liquid organic crystal from portion 1610-1 to portion 1610-2, which has a temperature below the melting point of the organic crystal, will cause the liquid organic crystal to form a solid organic crystal structure.

[0243] In some configurations, the ampoule is filled with organic solid crystals for further processing. Recrystallization occurs when the temperature of the ampoule is changed from above the melting temperature to below the melting temperature. This process can be repeated until the desired degree of crystallinity is achieved. In some embodiments, the method also includes fracture, polishing, or in-mold lamination to adjust surface roughness, thickness, and curvature.

[0244] Figure 16 Parts II, III, and IV illustrate exemplary ampoule-like structures that can be used to form organic crystals via the melt-recrystallization method described with respect to Part I. In some embodiments, the ampoule-like structure includes nucleation regions and crystal growth regions. For example, Figure 16 The ampoule 1602 in Part II includes a nucleation region 1602-2 and a crystal growth region 1602-1. Figure 16 The ampoule 1612 in Part III includes a nucleation region 1612-2 and a crystal growth region 1612-1, and Figure 16 The ampoule 1618 in Part IV includes a nucleation region 1618-2 and a crystal growth region 1618-1. The nucleation region includes at least one nucleation channel having an inner diameter ranging from submicron to centimeter. For example, ampoule 1602 has a single nucleation channel corresponding to nucleation region 1602-2, and ampoule 1612 has multiple nucleation channels 1616. The channels (e.g., curved cylinders / straight cylinders) are configured to adjust the lattice type and orientation. The nucleation region is connected to the crystal growth region, which is larger in at least one dimension compared to the nucleation channel. The crystal growth region is configured to define the shape and size of the organic solid crystal. Examples include flat plates (e.g., the crystal growth region 1612-1 of ampoule 1612 corresponds to plate 1614), curved plates, cuboids, cylinders (e.g., the crystal growth region 1602-1 of ampoule 1602 corresponds to a cylinder), etc. In some embodiments, the ampoule also includes a double-walled structure, wherein the gap is filled with a cushioning material (e.g., the same organic solid crystal) to reduce the effects of thermal expansion mismatch between the ampoule and the organic solid crystal when temperature changes during processing. For example, ampoule 1618 includes an inner wall 1620-2 and an outer wall 1620-1. The organic crystal is grown within a cylinder defined by the inner wall 1620-2. In some embodiments, the gap defined by the inner wall 1620-2 and the outer wall 1620-1 is filled with a cushioning material.

[0245] In some embodiments, the ampoule-like material includes a block for mechanical support and a surface in contact with the organic crystal to control molecular orientation, thereby controlling crystal orientation. In some embodiments, the surface is primarily made of a crystalline fluoropolymer (e.g., PTFE, PDVF). The fluoropolymer can be formed with long chains having substantially parallel to one of the in-plane directions or perpendicular to the in-plane direction. In some embodiments, the surface is primarily made of a polyolefin polymer (e.g., PE). The polyolefin polymer can be formed with long chains having substantially parallel to one of the in-plane directions or perpendicular to the in-plane direction. In some embodiments, the surface is primarily made of a liquid crystal polymer having a nematic phase, which allows the liquid crystal polymer molecules to align in a pre-designed direction. In some embodiments, the surface is primarily made of an alignment layer (e.g., a photoalignment layer, a polyimide with uniaxial friction). In some embodiments, the surface is primarily made of an amorphous polymer with low surface energy (e.g., organosilicon, siloxane) to form a controlled nucleation surface. In some embodiments, the surface corresponds to the above-described... Figure 1A The alignment structure 110 is described. In some embodiments, the controlled nucleation surface comprises a non-polymer controlled nucleation surface comprising one or more organic structures selected from the group consisting of organic structures of formulas 6-1 to 6-5 described above. The molecular orientation of the organic solid crystal is controlled by surface energy matching. In some embodiments, the surface is made primarily of an amorphous inorganic material (e.g., SiO2). Optionally, the inorganic surface is functionalized with alkyl / alkoxysilanes. In some embodiments, the substrate and surface are made of the same material, which has been highly oriented by stretching and heating in one direction. Examples include PEN, polyolefins, and polyimides. In some embodiments, the substrate is made of a material different from the surface. Examples include inorganic amorphous materials such as SiO2, fused silica, quartz, organosilicon, and siloxanes; and inorganic crystalline materials such as silicon, siloxanes, SiC, and sapphire. Organic materials, such as polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups (e.g., polytetrafluoroethylene, Teflon, PFA, polyethylene naphthalate, polystyrene, polyolefins).

[0246] Figure 17 The illustration depicts a method for manufacturing organic crystals using solvent coating and zone annealing according to some embodiments. In some embodiments, the growth of organic solid crystals includes solvent-assisted coating followed by zone annealing. The solvent coating system includes a doctor blade (e.g., for spreading the coating material and creating a meniscus region at the front of the coating layer to control solvent evaporation) for spreading the coating material. Figure 17The coating includes a scraper 1702 (as described in Part I), a nozzle (e.g., nozzle 1704) for conveying the organic solid crystal solution to the front of the coating layer, a substrate (e.g., substrate 1708) for supporting the organic solid crystal, and a temperature controller for the substrate for controlling solvent evaporation. In some embodiments, the solvent-coated substrate is annealed in a zone annealing system. In some embodiments, the zone annealing system includes one or more heating zones (e.g., in...). Figure 17 The zone annealing system includes a heated zone (e.g., a zone 1718 heated in Part III) and one or more cooling zones (e.g., cooling zone 1714) to control the temperature profile. In some embodiments, the zone annealing system includes an automated arm that pushes a substrate (e.g., a substrate 1708 comprising an organic crystal coating) through the heated and cooled zones at a controlled speed. In some embodiments, the zone annealing system includes a controlled atmosphere (e.g., vacuum, inert gas, solvent vapor / non-solvent vapor). For example, in Figure 17 The zone annealing system described in Part III is positioned in relation to Figure 15 The chamber 1500 described is used to provide a controlled atmosphere environment.

[0247] In some embodiments, substrate 1708 includes bulk elements and surface modifications, wherein the bulk elements provide mechanical support and heat transfer, and the surface modifications control the orientation of molecules, thus controlling crystal orientation. In some embodiments, substrate 1708 corresponds to the above-mentioned... Figure 1A The substrate 105 is described. In some embodiments, surface modification includes or corresponds to... Figure 1AThe alignment structure 110 is described. In some embodiments, the modified surface is primarily made of a crystalline fluoropolymer (e.g., PTFE, PDVF). The fluoropolymer can be formed with long chains having substantially parallel to one of the in-plane directions or perpendicular to the in-plane direction. In some embodiments, the modified surface is primarily made of a polyolefin polymer (e.g., PE). The polyolefin polymer can be formed with long chains having substantially parallel to one of the in-plane directions or perpendicular to the in-plane direction. In some embodiments, the modified surface is primarily made of a liquid crystal polymer having a nematic phase, which allows the liquid crystal polymer molecules to align in a pre-designed direction. In some embodiments, the modified surface is primarily made of an alignment layer (e.g., a photoalignment layer, a polyimide with uniaxial friction). In some embodiments, the modified surface is primarily made of an amorphous polymer with low surface energy (e.g., organosilicon, siloxane) to form a controlled nucleation surface. The molecular orientation of the organic solid crystal is controlled by surface energy matching. In some embodiments, the modified surface is primarily made of an amorphous inorganic material (e.g., SiO2). Optionally, the inorganic surface is functionalized with alkyl / alkoxysilanes. In some embodiments, the substrate and the modified surface are made of the same material, which has been highly oriented by stretching and heating in one direction. Examples include PEN, polyolefins, and polyimides. In some embodiments, the substrate is made of a material different from that of the modified surface. Examples include inorganic amorphous materials such as SiO2, fused silica, quartz, organosilicon, siloxanes; inorganic crystalline materials such as silicon, siloxanes, SiC, and sapphire; and organic materials such as polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups (e.g., polytetrafluoroethylene, Teflon, PFA, polyethylene naphthalate, polystyrene, polyolefins). In some embodiments, the substrate includes a sandwich configuration in which a buffer layer (e.g., the same organic solid crystal) is sandwiched between two substrates. Optionally, the substrate also includes at least one microchannel on the modified surface (e.g., in... Figure 17 In Part II, microchannels 1710 are located on substrate 1708, wherein the shape, size, or orientation of the microchannels varies to conform to a crystallization round. Optionally, the process of the organic solid crystal also includes layering from the substrate, cutting, or laminating within a mold to adjust the shape and curvature.

[0248] In some implementations, the scraper also includes microstructures to facilitate mass transfer of organic solid crystal molecules from solution to the crystallization front.

[0249] According to some embodiments, growing organic solid crystals involves the field-assisted deposition of organic molecules with controlled alignment. The deposition system includes an anode, a cathode, and an intervening gap, wherein the electric field can be modulated and drive organic solid crystal molecules in solution to crystallize on the surfaces of the electrodes with controlled crystallinity. In some embodiments, each electrode further includes a conductive layer (e.g., ITO, a conductive polymer) on its first surface.

[0250] In some embodiments, the growth of organic solid crystals includes gel spinning. During gel spinning, the organic solid crystal (e.g., a crystalline polymer, such as polyethylene naphthalate) is fed into an extruder along with a solvent and converted into a spinning solution, which is then spun through a spinning plate containing more than one spinning orifice. The fluid fibers are further cooled to form gel fibers. Fiber stretching occurs before, during, or after solvent evaporation to promote chain alignment and crystallinity. The process also includes thermal compression, in which compressive forces are applied to unidirectionally arranged fibers at high temperatures.

[0251] In some embodiments, the organic solid-state crystal fabricated by the methods described herein operates as a waveguide combiner. In some embodiments, the organic solid-state crystal is operated as a diffractive lens (e.g., a Fresnel lens, a meta-lens) or a polarization-selective grating by additional processes such as patterning and etching, injection molding, nanoimprint lithography, or electrodeposition to apply the structure.

[0252] Furthermore, according to the disclosed technical solutions, forming (e.g., growing) a solid crystal on one or more alignment structures can also improve the electronic performance of electronic devices including the formed solid crystal. Forming (e.g., growing) a solid crystal on one or more alignment structures allows for the provision of controllable strain by adjusting the alignment structures, enabling the solid crystal to achieve a specific desired lattice. In some embodiments, strain can vary across the solid crystal; for example, strain can vary within the same device based on the disclosed solid crystal. In some embodiments, strain can vary across multiple solid crystals disposed on the same substrate (e.g., disposed on the same substrate); for example, strain can vary across multiple devices including corresponding solid crystals. In some embodiments, strain can vary in a specific spatial pattern (such as a PBP-type pattern), which can contribute to novel electronic transport properties.

[0253] Although these methods are described in relation to organic solid crystal films of a certain size produced by such methods, these methods can be used to produce organic solid crystal films of any other size (e.g., a first size less than 100 μm and a second size less than 1 cm).

[0254] Based on these principles, we now turn to certain implementation schemes.

[0255] According to some implementation schemes, optical films (e.g., Figure 1A and Figure 1D The solid crystal 115 in the text includes an organic solid crystal film formed from continuous organic solid crystals. The organic solid crystal film has a first dimension (e.g., thickness, such as...) of not less than 100 micrometers. Figure 1D The first dimension is D2) and a second dimension that is not less than 1 cm different from the first dimension (e.g., width such as dimension D1, or depth such as D3).

[0256] In some implementations, the second dimension is not less than three centimeters.

[0257] In some embodiments, the organic solid crystal film is curved or flat (e.g., solid crystal 115 has...). Figure 1C The flat shape shown in Part I and Part III or Figure 1C (The curved shape shown in Part II and Part IV).

[0258] In some implementations, the refractive index of the optical film is at least 1.6.

[0259] In some implementations, perpendicular to (e.g., Figure 1C Parts III and IV) or parallel to (e.g., Figure 1C The refractive index of the optical film, measured in the direction of the surface defined by the organic solid crystal film (Part I and Part II), is at least 1.6, and the optical anisotropy of the organic solid crystal film is at least 0.03.

[0260] In some implementations, the optical anisotropy of the optical film is at least 0.1.

[0261] In some implementations, the organic solid crystal film includes monocrystalline or polycrystalline forms.

[0262] In some implementations, organic solid crystal films (e.g., Figure 1A and Figure 1D Solid crystals 115) include one or more organic crystals selected from the group consisting of: naphthalene, anthracene, tetraphenylene, pentaphenylene, pyrene, polyene, fluoranthene, benzophenone, benzochromene, benzoyl, benzimazole, benzene, hexachlorobenzene, nitropyridine-N-oxide, benzene-1,4-dicarboxylic acid, diphenylacetylene, N-(4-nitrophenyl)-(s)-proline, 4,5-dicyanimazole, benzodithiophene, cyanopyridine, thienothiophene, stilbene, azobenzene and its derivatives.

[0263] In some implementations, organic solid crystal films (e.g., Figure 1A and Figure 1DThe solid crystal 115 in the embodiment includes one or more ring structures, said ring structures comprising saturated cyclic groups selected from the group consisting of cyclohexane, cyclopentane, tetrahydropyran, piperidine, tetrahydrofuran, pyrrolidine, tetrahydrothiophene and their derivatives, and unsaturated aromatic groups selected from the group consisting of benzene, naphthalene, anthracene, thiophene, biphenyl, diphenylacetylene, benzimidazole, diphenylacetylene, cyanopyridine, thiophene-thiophene, dibenzothiophene, carbazole, silfluorene and their derivatives.

[0264] In some implementations, one or more ring structures are coupled to one or more of the following: C1-C 10 Alkyl, alkoxy, alkenyl groups, -CN, -NCS, -SCN, -SF5, -Br, -Cl, -F, -OCF3, -CF3, and monofluorinated or polyfluorinated C1-C 10 Alkyl or alkoxy.

[0265] In some implementations, organic solid crystal films (e.g., Figure 1A and Figure 1D The solid crystal 115) comprises one or more crystalline polymers having a precursor with an aromatic hydrocarbon or heteroaromatic hydrocarbon group and its derivatives. The one or more crystalline polymers are selected from the group consisting of: polyethylene naphthalate, poly(vinylphenyl sulfide), poly(α-methylstyrene), polythiophene, polythiophene, poly(n-vinylphthalimide), poly(p-xylene), polysulfides, polysulfones, poly(bromophenyl), poly(vinylnaphthalene), and liquid crystal polymers having precursors.

[0266] In some implementations, organic solid crystal films (e.g., Figure 1A and Figure 1D The solid crystal 115) is a combination of the following: an amorphous polymer having an aliphatic group, a heteroaliphatic group, an aromatic hydrocarbon group or a heteroaromatic group; a fatty acid, a lipid or a plasticizer; and a surfactant including molecules having a monofluorinated or polyfluorinated alkyl group or an alkoxy group.

[0267] In some embodiments, the organic solid crystal film comprises one or more organic crystals selected from the group consisting of organic solid crystal molecules of formulas 1-1 to 1-46, 2-1 to 2-4 and 3-1 to 3-28 as described above.

[0268] In some implementations, optical films are used to fabricate waveguide combiners (e.g., Figure 10B Combiner 1015), diffraction lens (e.g., Figures 9A-9C The device 900, which operates as a diffraction lens or diffraction grating, or a polarization selection grating (e.g., Figures 7A-7D PBP optical device 700 in the middle.

[0269] According to some embodiments, methods for manufacturing optical films include using physical vapor phase transport on a substrate having a controlled nucleation surface (e.g., Figure 15 The method involves depositing evaporated organic crystal molecules (e.g., evaporated organic crystal molecules 1506 from source material 1504) onto a substrate 1502 having a controlled nucleation surface 1502-1. The method also includes recrystallizing the evaporated organic crystal molecules on the controlled nucleation surface to form an optical film comprising a continuous organic solid crystal (e.g., forming an optical film with respect to...). Figure 1A The described solid crystal 115). The organic solid crystal film has a first dimension of not less than 100 micrometers (e.g., Figure 1D The first dimension (D2) and a second dimension (e.g., dimension D1) that is not less than 1 cm larger than the first dimension.

[0270] In some implementations, the controlled nucleation surface (e.g., Figure 15 Surface 1502-1 in the middle has a flat shape or a curved shape (e.g., Figure 1C The flat or curved shape defines the shape of the optical film.

[0271] In some embodiments, the controlled nucleation surface includes one or more of the following: SiO2, fused silica, quartz, organosilicon, siloxane, silicon, SiC, sapphire, and polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups.

[0272] In some embodiments, the controlled nucleation surface includes a non-polymer-based coating layer selected from silyl fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, heteroaromatic groups, small organic molecule-based crystals, and organic structures of any one of Formulas 6-1 to 6-5 as described above.

[0273] In some implementations, the method further includes fracturing, polishing, or laminating controlled nucleation surfaces (e.g., Figure 15 The surface 1502-1 of the intermediate substrate 1502 is used to adjust the roughness, thickness, or curvature of the controlled nucleation surface.

[0274] In some embodiments, the substrate includes one or more of the following: SiO2, fused silica, quartz, organosilicon, siloxane, silicon, SiC, sapphire, and polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups.

[0275] In some implementations, the source material (e.g., source material 1504) comprises an organic single crystal having one or more lattice-matched surfaces.

[0276] In some implementations, physical gas transport includes the use of a combination of inert gas and solvent vapor (e.g., Figure 15 The transport vapor 1508 transports evaporated organic crystal molecules (e.g., evaporated organic crystal molecules 1506) from the source material (e.g., source material 1504) to the controlled nucleation surface. In some embodiments, the method further includes adjusting the flow rate of the combination of inert gas and solvent vapor (e.g., transport vapor 1508), the ratio of inert gas to solvent vapor, and / or curing kinetics to control the crystal growth rate and nucleation of the organic solid crystal film.

[0277] According to some embodiments, the method includes obtaining an ampoule having one or more nucleation portions and a crystal growth portion coupled to one or more nucleation portions. For example, in Figure 16 In this method, ampoule 1602 includes a nucleation portion 1602-2 and a crystal growth portion 1602-1. The ampoule is filled with an organic solid crystal source material. The method includes placing the ampoule within a first space of a chamber, thereby heating the organic solid crystal source material to a molten state (e.g., portion 1610-1 of chamber 1600). The first space has a first temperature (e.g., the temperature of portion 1610-1 of chamber 1600 is higher than the melting point temperature T of the source material). m The chamber also has a second space with a second temperature (e.g., portion 1610-2 of chamber 1600). The first and second spaces are separated by a door (e.g., door 1606). The method also includes transferring an ampoule (e.g., ampoule 1602) from the first space of the chamber to the second space of the chamber, thereby recrystallizing the organic solid crystal source material to form a continuous organic solid crystal film having a first dimension of not less than 100 micrometers and a second dimension of not less than 1 centimeter, different from the first dimension.

[0278] In some embodiments, the crystal growth portion has the shape of a flat plate, a bent plate, a cuboid, or a cylinder (e.g., Figure 16 ).

[0279] In some implementations, ampoules (e.g., Figure 16 The ampoule 1618 in Part IV also includes a chassis defining one or more nucleation portions (e.g., nucleation portion 1618-2) and crystal growth portions (e.g., crystal growth portion 1618-1). The chassis includes a double-walled structure having a first wall (e.g., outer wall 1620-1) and a second wall (e.g., inner wall 1620-2). The double walls at least partially surround the respective nucleation regions of the one or more nucleation portions and the crystal growth portion. The chassis also includes a cushioning material placed between the first and second walls.

[0280] In some embodiments, the ampoule includes a controlled nucleation surface in contact with the organic solid crystal source material (e.g., ampoule 1602 includes an inner surface, which in some embodiments corresponds to...). Figure 1A The alignment structure described is 110. In some embodiments, the controlled nucleation surface has a flat or curved shape, which defines the shape of the optical film.

[0281] In some embodiments, the controlled nucleation surface includes one or more of the following: SiO2, fused silica, quartz, organosilicon, siloxane, silicon, SiC, sapphire, and polymers having fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, or heteroaromatic groups.

[0282] In some embodiments, the controlled nucleation surface includes a non-polymer-based coating layer selected from silyl fluorinated groups, alkyl groups, cyclic aliphatic groups, cyclic aromatic groups, heteroaromatic groups, and small organic molecule-based crystals.

[0283] According to some embodiments, a method for manufacturing an optical film includes a substrate (e.g., Figure 17 The substrate 1708 in the middle corresponds to having about Figure 1A The described alignment structure 110 is a solution of organic crystal molecules and solvent coated on the modified surface of a substrate 105). For example, the method includes applying the combination of organic crystal molecules and solvent onto a substrate 1708 through a nozzle 1704 and moving the substrate relative to a doctor blade 1702 to... Figure 17 A thin coating layer of organic crystal molecules is formed on substrate 1706 in Part I. This method involves varying the temperature of the organic crystal molecules deposited on the modified surface of the substrate and the solvent solution via zone annealing (e.g., by...). Figure 17 In Part III, a substrate 1708 with an organic crystal and solvent coating is moved between the heated region 1718 and the cooled region 1714, thereby causing the organic crystal molecules to crystallize to form a continuous organic solid crystal film having a first size of not less than 100 micrometers and a second size of not less than 1 centimeter, which is different from the first size.

[0284] In some implementations, the modified surface is configured to alter the interaction between the organic crystal molecules and the substrate in order to control the orientation of the organic crystal molecules and the number of defects in a continuous organic solid crystal film.

[0285] In some embodiments, the substrate includes at least one microchannel on the modified surface (e.g., Figure 17 The microchannel 1710 in Part II is used as a nucleation site for crystallization.

[0286] In some implementations, the coating includes using a scraper (e.g., Figure 17 The scraper 1702 in Part I spreads the organic crystal molecules and solvent solution, creating a meniscus region on the outer region of the solution.

[0287] In some implementations, the scraper includes more than one microstructure.

[0288] For illustrative purposes, the foregoing description of the implementation scheme has been presented. It is not intended to be exhaustive or to limit this disclosure to its precise form. Those skilled in the art will understand that modifications and variations are possible based on the above disclosure.

[0289] Some portions of this specification describe implementation schemes based on algorithms and symbolic representations of operations on information. While these operations are described functionally, computationally, or logically, they can be implemented by computer programs or equivalent circuits, microcode, or the like. Furthermore, referring to these arrangements of operations as modules, without loss of generality, has sometimes proven convenient. The described operations and their associated modules can be embodied in software, firmware, hardware, or any combination thereof.

[0290] Any step, operation, or process described herein may be performed or implemented using one or more hardware modules and / or software modules, either individually or in combination with other means. In one embodiment, the software module is implemented using a computer program product comprising a computer-readable medium containing computer program code executable by a computer processor for performing any or all of the described steps, operations, or processes.

[0291] Some embodiments may also relate to a device for performing the operations described herein. This device may be specifically constructed for a particular purpose, and / or it may include a general-purpose computing device that can be selectively activated or reconfigured by a computer program stored in a computer. Such a computer program may be stored in a non-transitory, tangible, computer-readable storage medium, or any type of medium suitable for storing electronic instructions, which may be coupled to a computer system bus. Furthermore, any computing system mentioned in the specification may include a single processor, or may be an architecture employing a multiprocessor design to enhance computing power.

[0292] Some implementations may also involve products generated by the computational processes described herein. Such products may include information obtained from the computational processes, wherein the information is stored on a non-transitory, tangible, computer-readable storage medium, and may include any implementation of the computer program products or other combinations of data described herein.

[0293] Finally, the language used in the specification has been chosen primarily for readability and instruction purposes, and may not have been chosen to depict or limit the subject matter of the invention. Therefore, it is intended that the scope of this disclosure is not limited by this detailed description, but rather by any claims published on the application based thereon. Thus, the disclosure of the embodiments is intended to be illustrative, not restrictive, of the scope of this disclosure, which is set forth in the appended claims.

Claims

1. A method of making an optical film, the method comprising: obtaining an ampoule having one or more nucleation portions and a crystal growth portion coupled to the one or more nucleation portions, wherein the ampoule is filled with an organic solid crystal source material; placing the ampoule within a first space of a chamber, thereby heating the organic solid crystal source material to a molten state, the first space having a first temperature, the chamber further having a second space having a second temperature, the first space and the second space separated by a door; and transferring the ampoule from the first space of the chamber to the second space of the chamber, thereby recrystallizing the organic solid crystal source material to form a continuous organic solid crystal film having a first dimension of no less than 100 microns and a second dimension different from the first dimension of no less than 1 centimeter; wherein the organic solid crystal film is a combination of: an amorphous polymer having aliphatic groups, heteroaliphatic groups, aromatic hydrocarbon groups, or heteroaromatic hydrocarbon groups; a fatty acid, a lipid, or a plasticizer; and a surfactant comprising molecules having monofluorinated or polyfluorinated alkyl groups or alkoxy groups.

2. The method of claim 1, wherein the ampoule further comprises: a chassis defining the one or more nucleation portions and the crystal growth portion, the chassis comprising: a double-walled structure having a first wall and a second wall, the double wall at least partially surrounding respective nucleation regions of the one or more nucleation portions and the crystal growth portion; and a buffer material placed between the first wall and the second wall.

3. The method of claim 1, wherein the ampoule comprises a controlled nucleation surface in contact with the organic solid crystal source material.

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