A method of forming a waveguide section having a predetermined shape

Abstract

The present disclosure relates to a method of forming a waveguide portion having a predetermined shape. In an example method of forming a waveguide portion having a predetermined shape, a photo-curable material is dispensed into a space located between a first mold portion and a second mold portion opposite the first mold portion. A relative spacing between a surface of the first mold portion relative to a surface of the second mold portion opposite the surface of the first mold portion is adjusted to fill the space located between the first mold portion and the second mold portion. The photo-curable material in the space is irradiated with radiation suitable to photo-cure the photo-curable material to form a cured waveguide film such that different portions in the cured waveguide film have different stiffnesses. The cured waveguide film is separated from the first mold portion and the second mold portion. A waveguide portion is singulated from the cured waveguide film. The waveguide portion corresponds to a portion of the cured waveguide film having a higher stiffness than other portions of the cured waveguide film.

Description

[0001] This application is a divisional application of the application filed on October 16, 2019, with PCT international application number PCT / US2019 / 056519, Chinese national phase application number 201980082625.8, entitled "A method for forming a waveguide portion having a predetermined shape".

[0002] Cross-references to related applications

[0003] This application claims the benefit of U.S. Provisional Application Serial No. 62 / 746,414, filed October 16, 2018, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0004] This disclosure relates to optical polymer films and methods for preparing the same. Background Technology

[0005] Optical imaging systems, such as wearable imaging headsets, may include one or more eyepieces that present a projected image to a user. The eyepieces can be constructed using thin layers of one or more highly refractive materials. For example, the eyepiece may consist of one or more layers of highly refractive glass, silicon, metal, or polymer substrates.

[0006] In some cases, the eyepiece can be patterned (e.g., using one or more light diffraction nanostructures) so that it projects an image according to a specific depth of focus. For example, the projected image may appear to be at a specific distance from a user viewing a patterned eyepiece.

[0007] Furthermore, multiple eyepieces can be used in combination to project simulated 3D images. For example, multiple eyepieces—each with a different pattern—can be layered vertically, and each eyepiece can project a different depth layer of the volumetric image. Therefore, the eyepieces can work together across three dimensions to present a stereoscopic image to the user. This is useful, for example, in presenting a "virtual reality" environment to a user.

[0008] To improve the quality of the projected image, eyepieces can be constructed such that unexpected variations within them are eliminated or otherwise reduced. For example, an eyepiece can be configured so that it does not exhibit any wrinkles, uneven thickness, or other physical deformations that could negatively impact its performance. Summary of the Invention

[0009] This paper describes systems and techniques for preparing polymer films. One or more of the described implementations can be used to prepare polymer films in a highly precise, controlled, and reproducible manner. The resulting polymer films can be used in a variety of variation-sensitive applications where extremely tight tolerances to film dimensions are required. For example, polymer films can be used in optical applications (e.g., as part of an eyepiece in an optical imaging system) where material homogeneity and dimensional constraints are on the order of optical wavelengths or smaller.

[0010] Typically, as described herein, polymer films can be prepared by surrounding a photocurable material (e.g., a photopolymer or photoactivated resin that cures when exposed to light) between two molds and curing the material (e.g., by exposing the material to light and / or heat). Furthermore, a "singulation" process can be performed to separate the polymer film into multiple distinct products (e.g., by cutting the polymer film once or multiple times to obtain individual products with specific sizes and shapes) and / or to remove excess polymer material from the edges of the polymer products.

[0011] In some cases, performing monomerization processes can introduce undesirable variations into polymer films, making the resulting products less suitable for use in environments sensitive to change. For example, techniques such as die-cutting, milling, waterjet cutting, ultrasonic cutting, or laser cutting are sometimes used to perform monomerization to separate polymer films into distinct parts. However, if the polymer film is too brittle, it may chip or break during cutting, resulting in poor edge quality. These defects can negatively impact the fabrication process (e.g., making it more difficult to produce accurate and precise cuts during fabrication), thus reducing yields in applications requiring high-precision edges. Furthermore, these defects can make the resulting polymer products less suitable for their intended use. For example, chips and cracks can interfere with the intended optical properties of the polymer product and negatively affect its performance. As another example, this can generate debris, which can damage the polymer product and / or make it more difficult to stack polymer products together with high precision (e.g., in multi-optical devices). Additionally, these defects can increase the product-to-product variability of the polymer product. Therefore, polymer products may not be well-suited for use in applications that are sensitive to change.

[0012] This article describes example techniques for monomerizing polymer membranes. One or more of the described techniques can be performed to separate the polymer membrane into multiple distinct products while eliminating or otherwise reducing the occurrence of unwanted fragmentation or cracking. Therefore, polymer products can be prepared more efficiently, consistently, and accurately.

[0013] In one aspect, a method for forming a waveguide portion having a predetermined shape includes: dispensing a photocurable material into a space located between a first mold portion and a second mold portion opposite to the first mold portion; and adjusting the relative spacing between the surfaces of the first mold portion and the surfaces of the second mold portion opposite to the surface of the first mold portion to fill the space located between the first mold portion and the second mold portion. The method further includes irradiating the photocurable material in the space with radiation suitable for photocuring the photocurable material to form a cured waveguide film, such that different portions of the cured waveguide film have different stiffnesses. The method further includes: separating the cured waveguide film from the first mold portion and the second mold portion; and monomerizing the waveguide portion from the cured waveguide film. The waveguide portion corresponds to a portion of the cured waveguide film having a higher stiffness than other portions of the cured waveguide film.

[0014] This aspect can be implemented in ways that include one or more of the following features.

[0015] In some implementations, different portions of the photocurable material can be irradiated with varying doses of radiation. A portion of the photocurable material irradiated with a higher dose of radiation may correspond to a portion of the cured waveguide film that has higher stiffness than a portion irradiated with a lower dose. Different doses of radiation can be supplied by irradiating the space through a mask. The mask may include holes corresponding to a predetermined shape of the waveguide portion.

[0016] In some implementations, the waveguide portion has a thickness of no more than 1000 μm and a minimum thickness of 1 cm. 2 The area.

[0017] In another aspect, a method for forming a waveguide portion having a predetermined shape includes: dispensing a photocurable material into a space between a first mold portion and a second mold portion opposite to the first mold portion; and adjusting the relative spacing between the surfaces of the first mold portion and the surfaces of the second mold portion opposite to the surface of the first mold portion to fill the space between the first mold portion and the second mold portion. The method further includes irradiating the photocurable material in the space with radiation suitable for photocuring the photocurable material to form a cured waveguide film. The method also includes: separating the cured waveguide film from the first mold portion and the second mold portion to provide the waveguide portion; and monomerizing a portion of the cured waveguide film into a predetermined shape from the cured waveguide film, and annealing the monomerized portion to provide the waveguide portion. The waveguide portion has a higher stiffness than the cured waveguide film.

[0018] This aspect can be implemented in ways that include one or more of the following features.

[0019] In some implementations, the monomerized portion can be annealed by irradiating the monomerized portion with radiation suitable for photocuring the photocurable material.

[0020] In some implementations, the monomerized portion can be annealed by heating it.

[0021] In some implementations, the waveguide portion can have a thickness of no more than 1000 μm and a minimum thickness of 1 cm. 2 The area.

[0022] In another aspect, a method for forming a waveguide portion having a predetermined shape includes: positioning a frame between a first mold portion and a second mold portion, the frame having rigidity and defining a first hole having a predetermined shape; and dispensing a photocurable material into the hole of the frame. The method further includes: irradiating the photocurable material in the hole with radiation suitable for photocuring the photocurable material to form a cured waveguide film having a rigidity different from that of the frame; and separating the cured waveguide film from the first mold portion and the second mold portion. The method further includes monomerizing the waveguide portion from the cured waveguide film by cutting a path along the frame. The path at least partially surrounds the hole. The method further includes extracting the waveguide portion comprising the cured photocurable material from the frame along the path.

[0023] This aspect can be implemented in ways that include one or more of the following features.

[0024] In some implementations, the frame may define multiple holes, each with a predetermined shape. A photocurable material may be dispensed into each of the holes in the frame. The photocurable material in each hole may be simultaneously irradiated with radiation. The cured waveguide film may include the cured photocurable material in each of the holes.

[0025] In some implementations, the waveguide portion can have a thickness of no more than 1000 μm and a minimum thickness of 1 cm. 2 The area.

[0026] Details of one or more embodiments are set forth in the accompanying drawings and the following description. Other features and advantages will become apparent from the specification, the drawings, and the claims. Attached Figure Description

[0027] Figure 1 This is a diagram of an example system used to prepare polymers.

[0028] Figure 2 This is a diagram of an example mold structure with a spacer structure.

[0029] Figure 3This is a schematic diagram of an example process for preparing polymer products.

[0030] Figure 4 This is a schematic diagram of another example process for preparing polymer products.

[0031] Figure 5 A schematic diagram of an example monomerization framework used to prepare polymer products.

[0032] Figure 6 This is a diagram of an example system used to prepare polymers.

[0033] Figure 7 This is a cross-sectional view of an example optical film.

[0034] Figures 8A-8C This is a flowchart of an example process for preparing polymer products.

[0035] Figure 9 This is a diagram of an example computer system. Detailed Implementation

[0036] This document describes systems and techniques for preparing polymer films. One or more of the described implementations can be used to prepare polymer films in a highly precise, controlled, and reproducible manner. The resulting polymer films can be used in a variety of variation-sensitive applications (e.g., as part of an eyepiece in an optical imaging system).

[0037] In some implementations, polymer films can be prepared to eliminate or otherwise reduce wrinkles, uneven thickness, or other unintended physical deformations. This can be useful, for example, because the resulting polymer film exhibits more predictable physical and / or optical properties. For instance, polymer films prepared in this way can diffract light in a more predictable and consistent manner, and are therefore more suitable for use in high-resolution optical imaging systems. In some cases, optical imaging systems using these polymer films can produce sharper and / or higher resolution images than those produced by other polymer films.

[0038] An exemplary system 100 for preparing polymer films Figure 1 As shown in the figure. System 100 includes two actuable stages 102a and 102b, two mold structures 104a and 104b, two light sources 106a and 106b, a support frame 108, and a control module 110.

[0039] During operation of system 100, two mold structures 104a and 104b (also referred to as “optical flats”) are respectively fixed to (e.g., via clamps 112a and 112b) actuable stages 102a and 102b. In some cases, clamps 112a and 112b may be magnetic (e.g., electromagnets) and / or pneumatic clamps, which enable mold structures 104a and 104b to be reversibly mounted to and removed from actuable stages 102a and 102b. In some cases, clamps 112a and 112b may be controlled by a switch and / or control module 110 (e.g., by selectively applying electricity to the electromagnets of clamps 112a and 112b and / or selectively actuating pneumatic mechanisms to engage or disengage the mold structures).

[0040] A photocurable material 114 (e.g., a photopolymer or photoactivated resin that cures when exposed to light) is deposited into a mold structure 104b. Mold structures 104a and 104b are moved close to each other (e.g., by moving actuating stages 102a and / or 102b perpendicularly along the support frame 108), such that the photocurable material 114 is surrounded by the mold structures 104a and 104b. The photocurable material 114 is then cured (e.g., by exposing the photocurable material 114 to light from light sources 106a and / or 106b), thereby forming a film having one or more features defined by the mold structures 104a and 104b. After the photocurable material 114 has cured, the mold structures 104a and 104b are moved away from each other (e.g., by moving actuating stages 102a and / or 102b perpendicularly along the support frame 108), and the film is extracted.

[0041] Actuated stages 102a and 102b are configured to support mold structures 104a and 104b, respectively. Furthermore, actuated stages 102a and 102b are configured to manipulate mold structures 104a and 104b, respectively, in one or more dimensions to control the gap volume 116 located between mold structures 104a and 104b.

[0042] For example, in some cases, the actuated stage 102a can translate the mold structure 104a along one or more axes. As an example, the actuated stage 102a can translate the mold structure 104a along the x-axis, y-axis, and / or z-axis in a Cartesian coordinate system (i.e., a coordinate system with three orthogonally arranged axes). In some cases, the actuated stage 102a can rotate or tilt the mold structure 104a about one or more axes. As an example, the actuated stage 102a can rotate the mold structure 104a along the x-axis (e.g., causing the mold structure 104a to “roll”), y-axis (e.g., causing the mold structure 104a to “pitch”), and / or z-axis (e.g., causing the mold structure 104a to “deflect”) in a Cartesian coordinate system. Translation and / or rotation relative to one or more other axes are also possible, in addition to or instead of those described above. Similarly, the actuated stage 102b can also cause the mold structure 104b to translate along one or more axes and / or rotate about one or more axes.

[0043] In some cases, the actuated stage 102a can manipulate the mold structure 104a according to one or more degrees of freedom (e.g., one, two, three, four, or more degrees of freedom). For example, the actuated stage 102a can manipulate the mold structure 104a according to six degrees of freedom (e.g., translation along the x, y, and z axes, and rotation about the x, y, and z axes). Manipulation according to one or more other degrees of freedom is also possible, in addition to or instead of those described above. Similarly, the actuated stage 102b can also manipulate the mold structure 104b according to one or more degrees of freedom.

[0044] In some cases, actuated stages 102a and 102b may include one or more motor assemblies configured to manipulate mold structures 104a and 104b and control the gap volume 116. For example, actuated stages 102a and 102b may include motor assemblies 118 configured to manipulate actuated stages 102a and 102b to reposition and / or reorient actuated stages 102a and 102b.

[0045] exist Figure 1 In the example shown, both actuated stages 102a and 102b are movable relative to the support frame 108 to control the gap volume 116. However, in some cases, one of the actuated stages may be movable relative to the support frame 108, while the other may remain stationary relative to the support frame 108. For example, in some cases, actuated stage 102a may be configured to translate relative to the support frame 108 in one or more dimensions via the motor assembly 118, while actuated stage 102b may remain stationary relative to the support frame 108.

[0046] Mold structures 104a and 104b together define an enclosure for the photocurable material 114. For example, when mold structures 104a and 104b are aligned together, they can define a hollow mold region (e.g., gap volume 116) within which the photocurable material 114 can be deposited and cured into a film. Mold structures 104a and 104b can also define one or more structures in the resulting film. For example, mold structures 104a and 104b may include one or more protruding structures (e.g., gratings) originating from surfaces 120a and / or 120b, which impart corresponding channels in the resulting film. As another example, mold structures 104a and 104b may include one or more channels defined in surfaces 120a and / or 120b, which impart corresponding protruding structures in the resulting film. In some cases, mold structures 104a and 104b may impart specific patterns on one or both sides of the resulting film. In some cases, the mold structures 104a and 104b do not need to impart any pattern of protrusions and / or channels on the resulting film. In other cases, the mold structures 104a and 104b can define specific shapes and patterns such that the resulting film is suitable for use as an eyepiece in an optical imaging system (e.g., such that the film has one or more optical diffraction microstructures or nanostructures that impart special optical properties to the film).

[0047] In some cases, the surfaces of mold structures 104a and 104b that face each other can each be substantially flat, such that the gap volume 116 defined between them exhibits a TTV of 500 nm or less. For example, mold structure 104a may include a substantially flat surface 120a, and mold structure 104b may have a substantially flat surface 120b. A substantially flat surface can be, for example, a surface whose flatness deviates from an ideal flat surface (e.g., a perfectly flat surface) by 100 nm or less (e.g., 100 nm or less, 75 nm or less, 50 nm or less, etc.). A substantially flat surface can also have a local roughness of 2 nm or less (e.g., 2 nm or less, 1.5 nm or less, 1 nm or less, etc.) and / or an edge-to-edge flatness of 500 nm or less (e.g., 500 nm or less, 400 nm or less, 300 nm or less, 50 nm or less, etc.). In some cases, one or both surfaces of mold structures 104a and 104b may be polished (e.g., to further increase surface flatness). For example, substantially flat surfaces may be advantageous because they allow mold structures 104a and 104b to define a gap volume 116 that is substantially uniform in thickness (e.g., having a TTV of 500 nm or less) along the extent of mold structures 104a and 104b. Thus, the resulting optical film can be flat (e.g., having a total thickness variation [TTV] less than or equal to a certain threshold and / or a local thickness variation [LTV], such as less than 500 nm, less than 400 nm, less than 300 nm, etc.). Furthermore, polished mold structures 104a and 104b may be advantageous, for example, in providing a smoother optical film for optical imaging applications. For example, an eyepiece constructed with a smoother optical film may exhibit improved imaging contrast.

[0048] The TTV and LTV of the exemplary optical film 700 are in Figure 7 As shown in the figure. The TTV of optical film 700 refers to the maximum thickness of optical film 700 relative to the entire optical film 700 (T). 最大 Subtract the minimum thickness of the optical film (T) relative to the overall thickness of the optical film (700). 最小 (For example, TTV=T) 最大 -T 最小 The LTV of optical film 700 refers to the maximum thickness (T) of optical film 700 relative to a local portion of optical film 700. 局部最大 Subtract the minimum thickness (T) of the optical film 700 relative to a local portion of the optical film 700. 局部最小 (For example, LTV = T) 局部最大 - T 局部最小Depending on the application, the size of the local portion can vary. For example, in some cases, the local portion can be defined as a section of the optical film with a specific surface area. For instance, for an optical film intended to be used as an eyepiece in an optical imaging system, the surface area of ​​the local portion could be an area with a diameter of 2.5 inches. In some cases, depending on the eyepiece design, the surface area of ​​the local portion can vary. In some cases, depending on the size and / or characteristics of the optical film, the surface area of ​​the local portion can vary.

[0049] Mold structures 104a and 104b are also rigid, preventing them from flexing or bending during the film preparation process. The stiffness of mold structures 104a and 104b can be expressed in terms of their bending stiffness, which is a function of the elastic modulus of the mold structure (E) and the area quadratic moment (I) of the mold structure. In some cases, each mold structure may have a stiffness of 1.5 Nm. 2 Or greater bending stiffness.

[0050] Furthermore, mold structures 104a and 104b may be partially or completely transparent to radiation at one or more wavelengths (e.g., between 315 nm and 430 nm) suitable for photocuring the photocurable material. Furthermore, mold structures 104a and 104b may be made of materials that are thermally stable (e.g., unchanged in size or shape) up to a specific threshold temperature (e.g., up to at least 200 °C). For example, mold structures 104a and 104b may be made of glass, silicon, quartz, Teflon and / or polydimethylsiloxane (PDMS), and other materials.

[0051] In some cases, mold structures 104a and 104b can have thicknesses greater than a certain threshold (e.g., thicker than 1 mm, thicker than 2 mm, etc.). This is advantageous, for example, because sufficiently thick mold structures are more difficult to bend. Therefore, the resulting film is less likely to exhibit thickness irregularities. In some cases, the thicknesses of mold structures 104a and 104b can be within a specific range. For example, the thickness of each of mold structures 104a and 104b can be between 1 mm and 50 mm. The upper limit of this range can, for example, correspond to the limitations of the etching tools used to pattern mold structures 104a and 104b. In practice, other ranges are possible depending on the implementation.

[0052] Similarly, in some cases, mold structures 104a and 104b may have diameters greater than a certain threshold (e.g., greater than 3 inches). This can be advantageous, for example, because it allows for the simultaneous fabrication of relatively large films and / or multiple individual films. Furthermore, if unwanted particulate matter is trapped between the mold structures (e.g., between spacer structure 124 and the opposing mold structures 104a or 104b, e.g., at position 126), its impact on the flatness of the resulting film is reduced.

[0053] For example, for mold structures 104a and 104b with relatively small diameters, misalignment on one side of mold structures 104a and 104b (e.g., due to particulate matter trapped on one of the spacer structures 124, such as at position 126) can cause the thickness of the gap volume 116 to change relatively sharply along the range of mold structures 104a and 104b. Therefore, the resulting one or more films exhibit more abrupt changes in thickness (e.g., a steeper slope of thickness along the length of the film).

[0054] However, for the relatively large diameter mold structures 104a and 104b, misalignment on one side of the mold structures 104a and 104b will result in a more gradual change in the thickness of the gap volume 116 along the range of the mold structures 104a and 104b. Therefore, the resulting one or more membranes exhibit a more abrupt change in thickness (e.g., a relatively gentle slope in thickness along the length of the membrane). Thus, the sufficiently large diameter mold structures 104a and 104b are more “tolerant” of trapped particles and can therefore be used to prepare more consistent and / or flatter membranes.

[0055] As an example, if particles of 5 μm or smaller are trapped at points along the periphery of mold structures 104a and 104b (e.g., at location 126), and each of mold structures 104a and 104b has a diameter of 8 inches, then the interstitial volume with a horizontal surface area of ​​2 square inches within the boundaries of mold structures 104a and 104b will still have a TTV of 500 nm or smaller. Therefore, if a photocurable material is deposited within the interstitial volume, the resulting film will similarly exhibit a TTV of 500 nm or smaller.

[0056] Light sources 106a and 106b are configured to generate radiation of one or more wavelengths suitable for photocuring the photocurable material 114. Depending on the type of photocurable material used, the one or more wavelengths may differ. For example, in some cases, a photocurable material (e.g., a UV-curable liquid siloxane elastomer, such as poly(methyl methacrylate) or poly(dimethylsiloxane)) may be used, and correspondingly, the light source may be configured to generate radiation with wavelengths in the range of 315 nm to 430 nm to photocur the photocurable material. In some cases, one or more of the mold structures 104a and 104b may be transparent or substantially transparent to the radiation suitable for photocuring the photocurable material 114, such that radiation from light sources 106a and / or 106b can pass through the mold structures 104a and / or 104b and impact the photocurable material 114.

[0057] Control module 110 is communicatively coupled to actuated stages 102a and 102b and is configured to control gap volume 116. For example, control module 110 may receive measurements of gap volume 116 (e.g., distance between mold structures 104a and 104b at one or more locations) from sensor assembly 122 (e.g., a device having one or more capacitive and / or pressure-sensitive sensor elements) and, in response, reposition and / or reorient one or both of mold structures 104a and 104b (e.g., by sending commands to actuated stages 102a and 102b).

[0058] As an example, such as Figure 1 As shown, system 100 may include one or more spacer structures 124 (e.g., protrusions or gaskets) projecting from one or more surfaces of a mold structure (e.g., mold structure 104b) toward an opposing mold structure (e.g., mold structure 104a). The spacer structures 124 may each have substantially equal vertical height, such that when mold structures 104a and 104b are placed together (e.g., pressed together), the spacer structures 124 abut against mold structures 104a and 104b and define a substantially flat gap volume 116 between them.

[0059] Furthermore, the spacer structure 124 can be positioned close to and at least partially surrounding the regions of the mold structures 104a and 104b for receiving and curing the photocurable material 114. This can be advantageous, for example, because it allows the system 100 to prepare polymer films with low TTV and / or LTV without requiring the maintenance of low TTV and / or LTV across the entire extension of the mold structures 104a and 104b. For example, multiple different polymer films can be prepared without achieving low TTV across the entire volume between the mold structures 104a and 104b. Therefore, the yield of the preparation process can be increased.

[0060] For example, Figure 2 Exemplary mold structures 104a and 104b are shown, with a spacer structure 124 disposed between them. When mold structures 104a and 104b are placed together, the spacer structure 124 abuts against mold structures 104a and 104b and physically prevents mold structures 104a and 104b from being closer to each other than the vertical height 202 of the spacer structure 124. Because the vertical height 202 of each of the spacer structures 124 is substantially equal, a substantially flat gap volume 116 is defined between mold structures 104a and 104b. In some cases, the vertical height 202 of the spacer structure 124 may be substantially equal to the desired thickness of the resulting film.

[0061] The spacer structure 124 can be constructed from various materials. In some cases, the spacer structure 124 can be made of a material that is thermally stable (e.g., its size or shape remains unchanged) up to a specific threshold temperature (e.g., up to at least 200°C). For example, the spacer structure 124 can be made of materials such as glass, silicon, quartz, and / or Teflon. In some cases, the spacer structure 124 can be made of the same material as the mold structures 104a and / or 104b. In some cases, the spacer structure 124 can be made of a different material than the mold structures 104a and / or 104b. In some cases, one or more of the spacer structures 124 can be integrally formed with the mold structures 104a and / or 104b (e.g., etched from the mold structures 104a and / or 104b, imprinted onto the mold structures 104a and / or 104b by a photolithography process, or additively formed onto the mold structures 104a and / or 104b, for example, by an additive manufacturing process). In some cases, one or more of the spacer structures 124 may be separable from the mold structures 104a and / or 104b and may be fixed to or attached to the mold structures 104a and / or 104b (e.g., using glue or other adhesives).

[0062] Despite Figure 2 Two spacer structures 124 are shown, but this is only an illustrative example. In practice, any number of spacer structures 124 (e.g., one, two, three, four, or more) can protrude from mold structure 104a, mold structure 104b, or both. Furthermore, although... Figure 2 Spacer structures 124 are shown positioned along the periphery of mold structures 104a and 104b. In fact, each spacer structure 124 can be positioned anywhere along the range of mold structures 104a and 104b.

[0063] Furthermore, in some implementations, in addition to or in place of the spacer structure 124, other mechanisms can be used to define the gap volume between mold structures 104a and 104b. For example, the motor assembly 118 can be configured to manipulate the actuated stages 102a and 102b such that the mold structures 104a and 104b are separated from each other by a specific distance (e.g., in...). Figure 1 (in the z-direction or vertical direction). In some implementations, the motor assembly 118 may include a locking mechanism 128, which prevents the motor assembly 118 from further moving the actuated stages 102a and 102b once they are in a specific position relative to each other. The locking mechanism 128 may be selectively engaged and disengaged during the manufacturing process.

[0064] As described herein, polymer films can be prepared by surrounding a photocurable material (e.g., a photopolymer or photoactivated resin that cures when exposed to light) between two molds and curing the material (e.g., by exposing the material to light and / or heat). Furthermore, a “monomerization” process can be performed to separate the polymer film into multiple distinct products (e.g., by cutting the polymer film once or multiple times to obtain individual products with specific sizes and shapes) and / or to remove excess polymer material from the edges of the polymer products.

[0065] In some cases, performing monomerization processes can introduce undesirable variations into polymer films, making the resulting products less suitable for use in variable-sensitive environments. For example, techniques such as die-cutting, milling, waterjet cutting, ultrasonic cutting, or laser cutting are sometimes used to perform monomerization to separate polymer films into distinct parts. However, if the polymer film is too fragile, it may crack or break during cutting, resulting in poor edge quality. These defects can negatively impact the fabrication process (e.g., making it more difficult to produce accurate and precise cuts during fabrication), thus reducing yields in applications requiring high-precision edges. Furthermore, these defects can make the resulting polymer products less suitable for their intended use. For example, fragmentation and cracks can interfere with the intended optical properties of the polymer product and negatively affect its performance. As another example, this can generate debris that can damage the polymer product and / or make it more difficult to stack polymer products together with high precision (e.g., in multi-optical devices). Additionally, these defects can increase the variability of the polymer product between products. Therefore, the polymer product may be less suitable for use in variable-sensitive applications.

[0066] This article describes example techniques for monomerizing polymer membranes. One or more of the described techniques can be performed to separate the polymer membrane into multiple distinct products while eliminating or otherwise reducing the occurrence of unwanted fragmentation or cracking. Therefore, polymer products can be prepared more efficiently, consistently, and accurately.

[0067] In some cases, monomerization can be performed by cutting one or more portions of a polymer film that has not yet fully cured. Compared to a fully cured polymer film, these portions are less rigid and less brittle, making cutting less likely to result in breakage or fragmentation. For example, the curing of the polymer film can be controlled by adjusting the intensity of the light applied to the photocurable material during the curing process and / or the exposure time of that light.

[0068] In some cases, localized portions of the polymer film (e.g., "monomerization zones") can be selectively cured to a smaller extent than the rest of the polymer film. During the monomerization process, the polymer film can be cut along these monomerization zones. Because the monomerization zones are less rigid and less brittle, cutting is less likely to result in cracks or fragmentation, thus improving the quality of the resulting polymer product.

[0069] As an example, Figure 3 This is a simplified schematic diagram of an example process for preparing polymer products using system 100. For example, Figure 3 The process shown can be used to fabricate optical components, such as waveguides or eyepieces for use in wearable imaging headsets. For ease of illustration, parts of system 100 have been omitted.

[0070] In some cases, this process is particularly useful for fabricating waveguides or eyepieces suitable for use in headphones. For example, the process can be used to fabricate waveguides or eyepieces having a thickness and / or cross-sectional area sufficient to guide light and project light covering the field of vision of the headphone wearer. As an example, the process can be used to fabricate polymer products suitable for optical applications (e.g., as part of a waveguide or eyepiece in an optical imaging system). In some cases, this process is particularly useful for fabricating waveguides or eyepieces suitable for use in headphones. For example, the process can be used to fabricate waveguides or eyepieces having a thickness and / or cross-sectional area sufficient to guide light and project light covering the field of vision of the headphone wearer. As an example, the process can be used to fabricate waveguides or eyepieces having a thickness not exceeding 1000 µm (e.g., measured along the z-axis of a Cartesian coordinate system) (e.g., 800 µm or less, 600 µm or less, 400 µm or less, 200 µm or less, 100 µm or less, or 50 µm or less), and at least 1 cm. 2 The area (e.g., measured relative to the xy plane of a Cartesian coordinate system) (e.g., 5 cm)2 Or larger, 10 cm 2 Or larger, 50 cm 2 Or larger, for example, up to about 100 cm 2 Or smaller, up to approximately 1000 cm tall 2 Polymer products (or smaller) and having a predetermined shape. In some cases, the polymer film has a size of at least 1 cm (e.g., 2 cm or larger, 5 cm or larger, 8 cm or larger, 10 cm or larger, e.g., about 30 cm or smaller) in at least one direction in the xy plane.

[0071] like Figure 3 As shown in the left portion, mold structure 104b includes surface 120b. Mold structure 104b is configured such that, when mold structure 104b is joined with a corresponding mold structure 104a, they define one or more enclosed regions for casting and curing the photocurable material 114. Furthermore, surface 120b defines a plurality of regions 300a-d, each region corresponding to the size and shape of a different polymer product 302a-d (e.g., a waveguide or eyepiece).

[0072] Furthermore, as described above, mold structures 104a and 104b may also define one or more structures in the resulting film. For example, mold structures 104a and 104b may include one or more protruding structures from surfaces 120a and / or 120b of the mold structure, which impart corresponding channels in the resulting film. As another example, mold structures 104a and 104b may include one or more channels defined in surfaces 120a and / or 120b, which impart corresponding protruding structures in the resulting film. In some cases, mold structures 104a and 104b may define specific patterns such that the resulting film is suitable for use as a waveguide or eyepiece in an optical imaging system (e.g., such that the film has one or more optical diffraction microstructures or nanostructures that impart special optical properties to the film).

[0073] During the casting process, a certain amount of photocurable material 114 is applied to the mold structure 104b. The mold structures 104a and 104b are then moved closer to each other (e.g., by moving relative to each other). Figure 1 The described actuable stages 102a and / or 102b) cause the mold structures 104a and 104b to surround the photocurable material 114 (e.g., as described above). Figure 3 (As shown in the middle part).

[0074] In addition, the system includes a light source positioned on the mold structure 104b (e.g., regarding...). Figure 1A mask 304 is shown and described between light sources 106a and 104b. In some cases, the mask 304 may be positioned above the mold structure 104a (e.g., between the mold structure 104a and the light source). The mask 304 is configured to attenuate light emitted from the light source differently relative to different locations on the mold structures 104a and 104b, such that certain portions of the photocurable material 114 are exposed to stronger light from the light source compared to other portions of the photocurable material 114. For example, the mask 304 may define a plurality of window regions 306a-d that transmit light of a first intensity onto the photocurable material 114 positioned on regions 300a-d of the mold structure 104b. Furthermore, the mask 304 may include one or more attenuation regions 308 that transmit light of a second, lower intensity onto the photocurable material 114 positioned in the mold structure 104b on regions outside regions 300a-d. Therefore, the photocurable material 114 located in regions 300a-d is cured faster than the photocurable material 114 located outside regions 300a-d.

[0075] In some cases, mask 304 may be a fused silica mold or a thin wafer. Window regions 306a-d may be regions that are transparent or substantially transparent to light of wavelengths suitable for photocuring the photocurable material. In some cases, window regions 306a-d may have similar dimensions and / or shapes to regions 300a-d. One or more attenuation regions 308 may include one or more regions of structures or other features (e.g., light diffuser structures or gratings) for attenuating the intensity of light relative to those wavelengths. In some cases, attenuation regions 308 may attenuate the intensity of light by at least 10% (e.g., 10%, 20%, 30% or more).

[0076] The photocurable material 114 is then cured (e.g., by irradiating the photocurable material 114 with light suitable for photocuring the photocurable material 114), thereby forming a polymer film 300 having one or more features defined by the mold structures 104a and 104b.

[0077] like Figure 3 As shown in the right-hand portion, after the photocurable material 114 has cured, the polymer film 310 is extracted from the mold structures 104a and 104b or the polymer film 310 is “demolded” (e.g., by moving the mold structures 104a and 104b away from each other and removing the polymer film 310 between them).

[0078] Due to the localized attenuation of light through mask 304, certain portions of the polymer film 310 are cured more extensively than other portions. For example, portions 312a-d (e.g., corresponding to the size and shape of polymer product 302a-d) have been cured to a greater extent due to the transmission of light through window regions 306a-d of mask 304. However, portions 314 have been cured to a lesser extent due to the attenuated transmission of light through attenuation regions 308 in mask 304. Therefore, portions 312a-d are relatively more rigid and brittle than portions 314. In some cases, portions 312a-d may have a Young's modulus greater than 2.0 GPa, and portions 314 may have a Young's modulus between 1 GPa and 1.5 GPa.

[0079] The polymer membrane 310 can be monomerized by cutting along portions 312a-d to separate the polymer membrane 310 into different polymer products 302a-d. When the cutting is performed on a less rigid and less fragile portion of the polymer membrane 310 (e.g., along the “monomerization zone”), the cutting results in fewer cracks or fragments. Therefore, the quality of the polymer products 302a-d is improved (e.g., compared to polymer products formed from a fully cured monomerized polymer membrane). Furthermore, the polymer membrane can be cut more precisely, accurately, and consistently, resulting in lower product-to-product variability.

[0080] In some cases, the light source can be configured to emit light according to a specific spatial distribution to promote location-specific curing of the photocurable material. For example, the light source can be configured to emit higher intensity light along the regions in mold structures 104a and 104b corresponding to products 302a-d (e.g., regions 300a-d), while emitting lower intensity light along other parts of mold structures 104a and 104b (e.g., regions outside 300a-d). In some cases, the light source can emit highly directional and / or collimated light to precisely adjust the light exposure relative to specific portions of mold structures 104a and 104b.

[0081] In practice, the operating parameters of this process can vary depending on the implementation method. As an example, the photocurable material LPB-1102 (Mitsubishi) can be cured by exposing it to ultraviolet (UV) light. Mask 304 can selectively attenuate the light intensity relative to specific locations on the mold structure, such that the "monomerization region" of the polymer film (e.g., the area of ​​the polymer film to be cut during the monomerization process) is exposed to light with an intensity of approximately 15 to 75 mW / cm². 2The intensity of light varies between these values. As a result, the monomerized regions of the polymer film have a tensile modulus in the range of about 0.5 to 1.5 GPa. These portions are soft enough that they can be easily monomerized using die-cutting, waterjet, and / or milling techniques without breaking or cracking. Furthermore, the mask 304 can selectively transmit high intensity (e.g., light with an intensity between about 15 and 75 mW / cm²) light relative to other locations in the die structure (e.g., the portion of the polymer film corresponding to the polymer product). 2 The light intensity (between 10 and 300) is used to completely cure those parts. In some cases, depending on the light intensity, the exposure time can range from 10 to 300 seconds.

[0082] As another example, the thiol-ene-based photocurable material MLP-02 (Magic Leap) can also be cured by exposing it to UV light. The mask 304 can selectively attenuate the light intensity at specific locations relative to the mold structure, such that the monomerized regions of the polymer film are exposed to light with an intensity of approximately 15 to 150 mW / cm². 2 The intensity of light varies between these values. As a result, the monomerized regions of the polymer film have a tensile modulus in the range of about 0.5 to 1.5 GPa. These portions are soft enough that they can be easily monomerized using die-cutting, waterjet, and / or milling techniques without breaking or fracturing. Furthermore, the mask 304 can selectively transmit high intensity (e.g., light with an intensity between about 200 and 400 mW / cm²) light relative to other locations in the mold structure (e.g., the portion of the polymer film corresponding to the polymer product). 2 The light intensity (between 60 and 420 seconds) allows those parts to be completely cured. In some cases, depending on the light intensity, the exposure time can range from 60 to 420 seconds.

[0083] In some cases, photocurable materials can be partially cured into polymer films (e.g., less rigid and brittle polymer films than fully cured polymer films). During the monomerization process, the partially cured polymer film can be cut into one or more polymer products. Each of these polymer products can then be annealed to complete the curing process. Therefore, performing monomerization while the polymer film is not rigid or brittle can improve the quality of the resulting polymer products (e.g., by reducing cracks or fragmentation along their edges).

[0084] As an example, Figure 4 This is a simplified schematic diagram of another example process for preparing polymer products using system 100. For example, Figure 4The process shown can be used to fabricate optical components, such as waveguides or eyepieces for use in wearable imaging headsets. For ease of illustration, parts of system 100 have been omitted. (This is in relation to...) Figure 3 The process, described in a similar manner, is particularly useful for fabricating waveguides or eyepieces suitable for use in headphones. For example, the process can be used to fabricate waveguides or eyepieces with sufficient thickness and / or cross-sectional area to guide light and project light covering the field of vision of the headphone wearer.

[0085] like Figure 4 As shown in the left portion, mold structure 104b includes surface 120b. Mold structure 104b is configured such that, when mold structure 104b is joined with a corresponding mold structure 104a, they define one or more enclosed regions for casting and curing the photocurable material 114. Furthermore, surface 120b defines a plurality of regions 400a-d, each region corresponding to the size and shape of a different polymer product 402a-d (e.g., a waveguide or eyepiece).

[0086] Furthermore, as described above, mold structures 104a and 104b may also define one or more structures in the resulting film. For example, mold structures 104a and 104b may include one or more protruding structures from surfaces 120a and / or 120b of the mold structure, which impart corresponding channels in the resulting film. As another example, mold structures 104a and 104b may include one or more channels defined in surfaces 120a and / or 120b, which impart corresponding protruding structures in the resulting film. In some cases, mold structures 104a and 104b may define specific patterns such that the resulting film is suitable for use as a waveguide or eyepiece in an optical imaging system (e.g., such that the film has one or more optical diffraction microstructures or nanostructures that impart special optical properties to the film).

[0087] During the casting process, a certain amount of photocurable material 114 is applied to the mold structure 104b. The mold structures 104a and 104b are then moved closer to each other (e.g., by moving relative to each other). Figure 1 The described actuable stages 102a and / or 102b) cause the mold structures 104a and 104b to surround the photocurable material 114 (e.g., as described above). Figure 4 (As shown in the middle part).

[0088] The photocurable material 114 is then partially cured (e.g., by irradiating the photocurable material 114 with light suitable for photocuring it), thereby forming a partially cured polymer film 410 having one or more features defined by the mold structures 104a and 104b. In some cases, the photocurable material 114 can be partially cured by exposing it to an amount of light sufficient to harden the polymer film 410 until it has a stiffness and / or rigidity less than that of the final polymer products 402a-d. Furthermore, the photocurable material 114 can be cured to exhibit a degree of solidity (e.g., to allow it to retain its shape even if the mold structure 104a is “peeled” from the photocurable material 114). In some cases, the photocurable material 114 can be cured until it has a Young's modulus between 1 GPa and 1.5 GPa.

[0089] like Figure 4 As shown in the right-hand portion, after the photocurable material 114 has been partially cured, the polymer film 410 is extracted by “peeling” it from the mold structure 104a or by “demolding” the polymer film 410 (e.g., by moving the mold structures 104a and 104b away from each other). The polymer film 410 remains on the mold structure 104b.

[0090] Partially cured polymer film 410 can be monomerized by cutting it into different polymer products 402a-d. The partially cured polymer film 410 can be monomerized while still positioned on mold structure 104b. This can be advantageous, for example, because the flat surface of mold structure 104b can reduce bending or warping of the polymer film 410 during the monomerization process. Furthermore, when cutting is performed on a less rigid and less brittle (e.g., compared to a fully cured polymer film) partially cured polymer film 410, the cutting results in fewer cracks or fragments. Therefore, the quality of polymer products 402a-d is improved (e.g., compared to polymer products formed from a monomerized fully cured polymer film). Moreover, the polymer film can be cut more precisely, accurately, and consistently, resulting in lower variability between products.

[0091] Following the monomerization process, polymer products 402a-d are annealed to complete the curing process. As an example, polymer products 402a-d may be heated and / or exposed to additional light until they are fully cured (e.g., until they exhibit a specific degree of rigidity and / or stiffness greater than that of a partially cured polymer film). In some cases, polymer products 402a-d may be annealed until they have a Young's modulus greater than 2.0 GPa. Polymer products 402a-d may be annealed while they are still positioned on mold structure 104b. After annealing, polymer products 402a-d can be extracted from mold structure 104b (e.g., by “peeling” polymer products 402a-d from mold structure 104b).

[0092] In practice, the operating parameters of this process can vary depending on the implementation method. As an example, the photocurable material LPB-1102 (Mitsubishi) can be cured by exposing it to an environment with approximately 15 to 75 mW / cm². 2 The polymer is partially cured by UV light of varying intensities. The exposure time can range from 10 to 300 seconds, depending on the light intensity. This results in a partially cured polymer film with a tensile modulus in the range of approximately 0.5 to 1.5 GPa. The partially cured polymer film is soft enough to allow it to be easily monomerized using die-cutting, waterjet, and / or milling techniques without breaking or cracking. After monomerization, each polymer product can be annealed by exposing it to a heating cycle between 40°C and 150°C for a duration between 15 and 120 minutes.

[0093] As another example, the thiol-based photocurable material MLP-02 (Qiyue) can be cured by exposing it to light with a curability of approximately 15 to 150 mW / cm². 2 The photocurable polymer is partially cured by UV light of varying intensities. Depending on the light intensity, the exposure time can range from 60 to 420 seconds. This results in a partially cured polymer film with a tensile modulus in the range of approximately 0.5 to 1.5 GPa. The partially cured polymer film is soft enough to allow it to be easily monomerized using die-cutting, waterjet, and / or milling techniques without breaking or cracking. After monomerization, each polymer product can be annealed by exposing it to a heating cycle between 125°C and 250°C for 20 to 120 minutes. In some cases, the polymer product may shrink in size after heating cycles (depending on the degree of initial cross-linking of the photocurable material before annealing, e.g., shrinkage in thickness between 5 and 10).

[0094] In some cases, photocurable materials can be deposited within a monomeric framework. The monomeric framework can be made of one or more rigid but brittle materials, allowing it to be cut along its edges without introducing cracks or fragments. The photocurable material can be cured directly within the monomeric framework and monomerized into individual polymer products by cutting along the framework rather than along the photocurable material itself. This improves the quality of the resulting polymer products (e.g., because the polymer material is no longer being directly cut).

[0095] Figure 5 A plan view of an example monomeric framework 500 is shown. The monomeric framework 500 defines a plurality of pores 502a-d, each pore corresponding to a different polymer product. Furthermore, the monomeric framework 500 defines a network of channels 504 that interconnect the pores 502a-d.

[0096] The monomeric framework 500 is constructed of one or more rigid but not easily broken materials, such that it can be cut along its edges without introducing cracks or fragments. In some cases, the monomeric framework 500 may be constructed of one or more polymers that are transparent or partially transparent to light of a wavelength suitable for curing the photocurable material (e.g., UV wavelength), such as polycarbonate-based, acrylate-based, and / or polystyrene-based materials. In some cases, the monomeric framework 500 may include a polymer, such as Teflon, along the edges defining the pores 502a-d.

[0097] Depending on the implementation, the thickness of the monolithic frame 500 can vary. In some cases, the monolithic frame 500 can have a thickness at least 50 μm smaller than the height of the spacer structure 126 (e.g., 50 μm smaller than the height of the spacer structure, 100 μm smaller than the height of the spacer structure, 150 μm smaller than the height of the spacer structure, etc.) so that the monolithic frame 500 does not interfere with the interaction between the spacer structure 126 and the mold structures 104a and 104b.

[0098] During the preparation process, the monomerized framework 500 is positioned on top of the mold structure 104b (e.g., such that the holes 502a-d are aligned with corresponding portions of the defined polymer product features in the mold structure 104b). A photocurable material is dispensed into the holes 502a-d. The mold structures 104a and 104b are moved closer to each other (e.g., by moving relative to each other). Figure 1 The described actuable stages 102a and / or 102b are such that mold structures 104a and 104b surround the photocurable material within the monolithic frame 500.

[0099] After curing, the monomerization process is performed by cutting the monomerization frame 500 along the periphery of the holes 502a-d (e.g., along the path 506a-d that at least partially surrounds the holes 502a-d). Thus, each polymer product includes cured polymer material surrounded or “framed” by a portion of the monomerization frame 500.

[0100] While example mold structure 104a and monomerization frame have been shown and described above, these are merely illustrative examples. In practice, the configuration of each may differ depending on the implementation. As an example, the mold structure may include areas for casting and curing any number of different polymer products (e.g., one, two, three, four, five, or more), each polymer product having any size or shape. As another example, the monomerization frame may include any number of holes to accommodate the casting and curing of any number of polymer products (e.g., one, two, three, four, five, or more), each polymer product having any size or shape.

[0101] In some cases, system 100 also includes one or more heating elements to apply heat to the photocurable material during the curing process. This, for example, can facilitate the curing process. For example, in some cases, both heat and light can be used to cure the photocurable material. For example, the application of heat can be used to accelerate the curing process, make the curing process more efficient, and / or make the curing process more consistent. In some cases, heat can be used instead of light to perform the curing process. For example, the application of heat can be used to cure the photocurable material without the need for a light source.

[0102] exist Figure 6 An exemplary system 600 for preparing polymer films is shown. Typically, system 600 can be used with… Figure 1 The system 100 shown is similar. For example, system 600 may include two actuated stages 102a and 102b, two mold structures 104a and 104b, a support frame 108, and a control module 110. For ease of illustration, in Figure 6 The control module 110 is not shown.

[0103] However, in this example, system 600 does not include two light sources 106a and 106b. Instead, it includes two heating elements 602a and 602b, which are positioned adjacent to mold structures 104a and 104b, respectively. Heating elements 602a and 602b are configured to move together with mold structures 104a and 104b (e.g., via actuable stages 102a and 102b) and are configured to apply heat to the photocurable material 114 between mold structures 104a and 104b during the curing process.

[0104] The operation of heating elements 602a and 602b can be controlled by control module 110. For example, control module 110 can be communicatively coupled to heating elements 602 and 602b and can selectively apply heat to photocurable material 114 (e.g., by sending commands to heating elements 602a and 602b).

[0105] Example heating elements 602a and 602b are metal heating elements (e.g., nickel-chromium alloy or resistance wire), ceramic heating elements (e.g., molybdenum disilicide or PTC ceramic elements), polymer PTC heating elements, composite heating elements, or combinations thereof. In some cases, heating elements 602a and 602b may include metal plates to facilitate uniform heat transfer to mold structures 104a and 104b.

[0106] Despite Figure 6 Two heating elements 602a and 602b are shown, but in some cases, the system may include any number of heating elements (e.g., one, two, three, four or more), or may not include any heating elements at all. Furthermore, although system 600 is shown as not having light sources 106a and 106b, in some cases, the system may combine one or more light sources and one or more heating elements.

[0107] Figure 8A An example process 800 for preparing a polymer product is shown. Process 800 can be performed, for example, using system 100 or 600. In some cases, process 800 can be used to prepare a polymer film suitable for use in optical applications (e.g., as part of a waveguide or eyepiece in an optical imaging system). In some cases, the process is particularly useful for preparing waveguides or eyepieces suitable for use in headphones. For example, the process can be used to prepare a waveguide or eyepiece having a thickness and / or cross-sectional area sufficient to guide light and project light covering the field of view of the headphone wearer. As an example, the process can be used to prepare a waveguide or eyepiece having a thickness (e.g., measured along the z-axis of a Cartesian coordinate system) of at least 1 cm, not exceeding 1000 µm (e.g., 800 µm or less, 600 µm or less, 400 µm or less, 200 µm or less, 100 µm or less, or 50 µm or less). 2 (e.g., 5 cm) 2 Or larger, 10 cm 2 Or larger, 50 cm 2 Or larger, for example, up to about 100 cm 2 Or smaller, or as tall as approximately 1000 cm 2A polymer product having an area (e.g., measured relative to the xy plane of a Cartesian coordinate system or smaller) and a predetermined shape. In some cases, the polymer film has a dimension of at least 1 cm (e.g., 2 cm or larger, 5 cm or larger, 8 cm or larger, 10 cm or larger, e.g., about 30 cm or smaller) in one direction of the xy plane.

[0108] In process 800, a photocurable material is dispensed into the space between a first mold portion and a second mold portion opposite to the first mold portion (step 802). For example, regarding Figure 1-3 An example mold section is shown and described.

[0109] Adjust the relative spacing between the surface of the first mold portion and the surface of the second mold portion opposite to the surface of the first mold portion to fill the space located between the first mold portion and the second mold portion (step 804). For example, regarding Figure 1 and 2 An example technique for adjusting the relative spacing between two mold sections is shown and described.

[0110] The photocurable material in space is irradiated with radiation suitable for photocuring the material to form a cured waveguide film, such that different portions of the cured waveguide film have different stiffnesses (step 806). In some cases, different portions of the photocurable material are irradiated with different doses of radiation. The portion of the photocurable material irradiated with a higher dose of radiation may correspond to a portion of the cured waveguide film with higher stiffness than a portion of the waveguide film irradiated with a lower dose of radiation. In some cases, different doses of radiation are supplied by irradiating the space through a mask. The mask may include holes corresponding to a predetermined shape of the waveguide portion. For example, regarding... Figure 3 Example techniques and masks for selectively controlling the stiffness of waveguide films during photocuring are shown and described.

[0111] The cured waveguide film is separated from the first mold portion and the second mold portion (step 808). Then, a waveguide portion is single-unitized from the cured waveguide film (step 810). The waveguide portion corresponds to a portion of the cured waveguide film that has higher stiffness than other portions of the cured waveguide film. In some cases, techniques such as die-cutting, milling, waterjet cutting, ultrasonic cutting, or laser cutting can be used to single-unitize the waveguide portion.

[0112] Figure 8BAnother example process 820 for preparing polymer products is shown. Process 820 can be performed, for example, using system 100 or 600. Similar to process 800, process 800 can be used to prepare polymer films suitable for use in optical applications (e.g., as part of a waveguide or eyepiece in an optical imaging system), and may be particularly useful for preparing waveguides or eyepieces suitable for use in headphones. For example, this process can be used to prepare waveguides or eyepieces having a thickness and / or cross-sectional area sufficient to guide light and project light covering the field of view of the headphone wearer. As an example, this process can be used to prepare waveguides or eyepieces having a thickness not exceeding 1000 μm (e.g., as measured along the z-axis of a Cartesian coordinate system) and at least 1 cm 2 A polymer product having an area (e.g., measured relative to the xy plane of a Cartesian coordinate system) and a predetermined shape. In some cases, the polymer film may have a dimension of at least 1 cm in at least one direction in the xy plane.

[0113] In process 820, a photocurable material is dispensed into the space between a first mold portion and a second mold portion opposite to the first mold portion (step 822). For example, regarding Figure 1-3 An example mold section is shown and described.

[0114] Adjust the relative spacing between the surface of the first mold portion and the surface of the second mold portion opposite to that surface of the first mold portion to fill the space between the first mold portion and the second mold portion (step 824). For example, regarding Figure 1 and 2 An example technique for adjusting the relative spacing between two mold sections is shown and described.

[0115] The photocurable material in the space is irradiated with radiation suitable for photocuring the material to form a cured waveguide film (step 826). For example, regarding Figure 1 Example techniques and systems for irradiating photocurable materials are shown and described.

[0116] The cured waveguide film is separated from the first mold portion and the second mold portion to provide the waveguide portion (step 828). Then, the cured waveguide film portion is individualized from the cured waveguide film in a predetermined shape (830). In some cases, techniques such as die-cutting, milling, waterjet cutting, ultrasonic cutting, or laser cutting can be used to individualize the waveguide portion.

[0117] The monomerized portion is annealed to provide a waveguide portion (step 832). The waveguide portion has a higher stiffness than the cured waveguide film. In some implementations, the monomerized portion is annealed by irradiating it with radiation suitable for photocuring a photocurable material. In some implementations, the monomerized portion is annealed by heating it. For example, regarding... Figure 4 An example technique for annealing the monomerized portions of a waveguide film is shown and described.

[0118] Figure 8C Another example process 840 for preparing polymer products is shown. Process 840 can be performed, for example, using system 100 or 600. Similar to processes 800 and 820, process 840 can be used to prepare polymer films suitable for use in optical applications (e.g., as part of a waveguide or eyepiece in an optical imaging system), and may be particularly useful for preparing waveguides or eyepieces suitable for use in headphones. For example, this process can be used to prepare waveguides or eyepieces having a thickness and / or cross-sectional area sufficient to guide light and project light covering the field of view of the headphone wearer. As an example, this process can be used to prepare waveguides or eyepieces having a thickness not exceeding 1000 μm (e.g., as measured along the z-axis of a Cartesian coordinate system) and at least 1 cm 2 A polymer product having an area (e.g., measured relative to the xy plane of a Cartesian coordinate system) and a predetermined shape. In some cases, the polymer film may have a dimension of at least 1 cm in at least one direction in the xy plane.

[0119] In process 840, the frame is positioned between the first mold portion and the second mold portion (step 842). The frame has a specific rigidity. Furthermore, the frame defines a first hole with a predetermined shape. In some cases, the frame defines multiple holes, each with a predetermined shape. For example, regarding... Figure 1-3 Example mold sections are shown and described. For example, regarding... Figure 5 An example framework is shown and described.

[0120] The photocurable material is dispensed into the holes of the frame (step 844). In some cases, the photocurable material is dispensed into each hole of the frame.

[0121] The photocurable material in the holes is irradiated with radiation suitable for photocuring the material to form a cured waveguide film with a stiffness different from that of the frame (step 846). In some cases, the photocurable material in each hole is irradiated simultaneously. For example, regarding... Figure 1 Example techniques and systems for irradiating photocurable materials are shown and described.

[0122] The cured waveguide film is separated from the first mold portion and the second mold portion (step 848). Then, the waveguide portion comprising the cured photocurable material is singled from the cured waveguide film by cutting along a path along the frame and extracting it from the frame (step 850). This path at least partially surrounds the holes. In some cases, the cured waveguide film comprises cured photocurable material in each hole. In some cases, techniques such as die-cutting, milling, waterjet cutting, ultrasonic cutting, or laser cutting can be used to single out portions of the waveguide portion.

[0123] Some implementations of the subjects and operations described in this specification can be implemented in digital electronic circuits, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their equivalents, or combinations thereof. For example, in some implementations, control module 110 can be implemented using digital electronic circuits, or in computer software, firmware, or hardware, or combinations thereof. In another example, process 800 shown in FIG8 can be implemented at least partially using digital electronic circuits, or in computer software, firmware, or hardware, or combinations thereof.

[0124] Some of the implementations described in this specification can be implemented as one or more groups or modules of digital electronic circuits, computer software, firmware, or hardware, or a combination thereof. Although different modules can be used, each module does not have to be different, and multiple modules can be implemented on the same digital electronic circuits, computer software, firmware, or hardware, or combinations thereof.

[0125] Some implementations described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions encoded on a computer storage medium for execution by a data processing apparatus or for controlling the operation of a data processing apparatus. The computer storage medium can be or can be included in a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination thereof. Furthermore, although the computer storage medium is not a propagating signal, it can be a source or destination of computer program instructions encoded as artificially generated propagating signals. The computer storage medium can also be or be included in one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices).

[0126] The term "data processing device" encompasses all types of devices, apparatuses, and machines used for processing data, including, for example, programmable processors, computers, systems-on-a-chip, or a combination of the foregoing. The device may include special-purpose logic circuitry, such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application-Specific Integrated Circuits). In addition to hardware, the device may also include code that creates an execution environment for the computer program in question, such as code constituting processor firmware, protocol stacks, database management systems, operating systems, cross-platform runtime environments, virtual machines, or combinations thereof. The device and execution environment can implement a variety of different computing model infrastructures, such as web services, distributed computing, and grid computing infrastructures.

[0127] Computer programs (also known as programs, software, software applications, scripts, or code) can be written in any form of programming language, including assembly or interpreted languages, declarative or procedural languages. A computer program may, but does not necessarily, correspond to a file in a file system. A program may be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinating files (e.g., a file storing one or more modules, subroutines, or code sections). A computer program can be deployed to execute on a single computer or on multiple computers located at a single site or distributed across multiple sites and interconnected through a communication network.

[0128] Some of the processes and logical flows described in this specification can be executed by one or more programmable processors executing one or more computer programs to perform actions by manipulating input data and generating output. The processes and logical flows can also be executed by dedicated logic circuitry, and the device can also be implemented as dedicated logic circuitry, such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application-Specific Integrated Circuit).

[0129] For example, processors suitable for executing computer programs include both general-purpose and special-purpose microprocessors, as well as processors in any type of digital computer. Typically, a processor receives instructions and data from read-only memory or random access memory, or both. A computer includes a processor for performing actions according to instructions and one or more storage devices for storing instructions and data. A computer may also include one or more mass storage devices (e.g., magnetic disks, magneto-optical disks, or optical disks) for storing data, or be operatively coupled to one or more mass storage devices (e.g., magnetic disks, magneto-optical disks, or optical disks) to receive data from or transfer data to one or more mass storage devices, or both. However, a computer does not necessarily need to have such devices. Devices suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and storage devices, such as semiconductor memory devices (e.g., EPROM, EEPROM, flash memory devices, etc.), magnetic disks (e.g., internal hard disks, removable disks, etc.), magneto-optical disks, and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by or incorporated into special-purpose logic circuitry.

[0130] To provide interaction with a user, operations can be performed on a computer having a display device (e.g., a monitor or other type of display device) for displaying information to the user and a keyboard and pointing device (e.g., a mouse, trackball, tablet, touchscreen, or other type of pointing device) that the user can use to provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback, such as visual, auditory, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input. Additionally, the computer can interact with the user by sending documents to and receiving documents on the device the user is using; for example, by sending web pages to a web browser on the user's client device in response to a request received from a web browser.

[0131] A computer system may include a single computing device or multiple computers that operate close to or typically far from each other and typically interact via a communication network. Examples of communication networks include local area networks (“LANs”) and wide area networks (“WANs”), the Internet (e.g., the Internet), networks including satellite links, and peer-to-peer networks (e.g., ad hoc point-to-point networks). Client-server relationships can be established by means of computer programs running on the respective computers and having client-server relationships with each other.

[0132] Figure 9An exemplary computer system 900 is illustrated, which includes a processor 910, a memory 920, a storage device 930, and an input / output device 940. Each of components 910, 920, 930, and 940 may be interconnected, for example, via a system bus 950. The processor 910 is capable of processing instructions that execute within the system 900. In some implementations, the processor 910 is a single-threaded processor, a multi-threaded processor, or another type of processor. The processor 910 is capable of processing instructions stored in the memory 920 or on the storage device 930. The memory 920 and the storage device 930 can store information within the system 900.

[0133] Input / output device 940 provides input / output operations for system 1600. In some implementations, input / output device 940 may include one or more of network interface devices such as Ethernet cards, serial communication devices such as RS-232 ports, and / or wireless interface devices such as 802.11 cards, 3G wireless modems, 4G wireless modems, etc. In some implementations, input / output device may include driver devices configured to receive data and send output data to other input / output devices, such as keyboards, printers, and display devices 960. In some implementations, mobile computing devices, mobile communication devices, and other devices may be used.

[0134] While this specification contains numerous details, these details should not be construed as limiting the scope of claims, but rather as descriptions of features specific to particular examples. Certain features described in this specification within the context of individual implementations may also be combined. Conversely, various features described in the context of a single implementation may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0135] Many implementations have been described. However, it should be understood that various modifications can be made without departing from the spirit and scope of the invention. Therefore, other implementations are within the scope of the following claims.

Claims

1. A method for forming a waveguide section, comprising: The photocurable material is dispensed into the space between the first mold portion and the second mold portion opposite to the first mold portion; The photocurable material is irradiated with radiation suitable for photocuring the photocurable material to form a cured waveguide film, such that different portions of the cured waveguide film have different stiffness. Separate the cured waveguide film from the first mold portion and the second mold portion; as well as The solidified waveguide film is cut to create a waveguide portion. The waveguide portion corresponds to the portion of the cured waveguide film that has higher stiffness than other portions of the cured waveguide film.

2. The method according to claim 1, wherein, Different portions of the photocurable material are irradiated with different amounts of radiation.

3. The method according to claim 2, wherein, The portion of the photocurable material irradiated with a larger amount of radiation corresponds to the portion of the cured waveguide film that has higher stiffness than the portion of the waveguide film irradiated with a smaller amount of radiation.

4. The method according to claim 2, wherein, Different amounts of radiation are supplied by illuminating the space through a mask.

5. The method according to claim 4, wherein, The mask includes holes corresponding to the shape of the waveguide portion.

6. The method according to claim 1, wherein, The waveguide portion has a thickness of no more than 1000 μm and a span of at least 1 cm. 2 The area.

7. The method according to claim 1, wherein, At least some of the other portions of the cured waveguide film surround the portion of the cured waveguide film corresponding to the waveguide portion.

8. The method according to claim 1, further comprising: Multiple waveguide sections are cut from the solidified waveguide film. The plurality of waveguide portions correspond to portions of the cured waveguide film that have higher stiffness than other portions of the cured waveguide film.

9. A method for forming a waveguide section, comprising: The photocurable material is dispensed into the space between the first mold portion and the second mold portion opposite to the first mold portion; The photocurable material in the space is irradiated with radiation suitable for photocuring the photocurable material to form a cured waveguide film. Cut a portion of the cured waveguide film to create a cut portion that is separated from the cured waveguide film; The cut portion is annealed to provide the waveguide portion. The waveguide portion has a higher stiffness than the solidified waveguide film.

10. The method according to claim 9, wherein, The cut portion is annealed by irradiating it with radiation suitable for photocuring the photocurable material.

11. The method according to claim 9, wherein, The cut portion is annealed by heating it.

12. The method according to claim 9, wherein, The waveguide portion has a thickness of no more than 1000 μm and a minimum diameter of 1 cm. 2 The area.

13. The method of claim 9, further comprising: Multiple portions of the cured waveguide film are cut from the cured waveguide film to produce multiple cut portions; The plurality of cut sections are annealed to provide a plurality of waveguide sections.

14. A method for forming a waveguide section, comprising: The frame is positioned in the space between the first mold portion and the second mold portion, the frame having a first rigidity, and the frame defining a hole; Dispense the photocurable material into the holes of the frame; The photocurable material in the hole is irradiated with radiation suitable for photocuring the photocurable material to form a cured waveguide film having a second stiffness different from the first stiffness. The waveguide portion is separated from the cured waveguide film by cutting a path along the frame, the path at least partially surrounding the hole; as well as The waveguide portion comprising the cured photocurable material is extracted from the frame along the path.

15. The method according to claim 14, wherein, The frame defines one or more additional holes.

16. The method according to claim 15, wherein, The photocurable material is dispensed into each of the holes in the frame.

17. The method according to claim 16, wherein, The photocurable material in each of the holes is simultaneously irradiated with the radiation.

18. The method according to claim 17, wherein, The cured waveguide film comprises the cured photocurable material in each of the holes.

19. The method of claim 14, wherein, The waveguide portion has a thickness of no more than 1000 μm and a minimum diameter of 1 cm. 2 The area.

20. The method of claim 14, wherein, The first stiffness is greater than the second stiffness.

21. An apparatus for forming a waveguide portion, comprising: First mold part; Second mold section; Radiation source; as well as Cut components; The device is configured as follows: A photocurable material is received in the space between the first mold portion and the second mold portion opposite to the first mold portion. The photocurable material is irradiated with radiation suitable for photocuring by the radiation source to form a cured waveguide film, such that different portions of the cured waveguide film have different stiffness. Separate the cured waveguide film from the first mold portion and the second mold portion, and The waveguide portion is cut from the cured waveguide film using the cutting assembly. The waveguide portion corresponds to the portion of the cured waveguide film that has higher stiffness than other portions of the cured waveguide film.

22. The apparatus according to claim 21, wherein, The device is configured to irradiate different portions of the photocurable material with different amounts of radiation.

23. The apparatus of claim 22, further comprising a mask, in, The device is configured to supply different amounts of radiation by illuminating the space through the mask.

24. The apparatus according to claim 23, wherein, The mask includes holes corresponding to the shape of the waveguide portion.

25. The apparatus according to claim 21, wherein, The device is also configured to: Multiple waveguide sections are cut from the solidified waveguide film. The plurality of waveguide portions correspond to portions of the cured waveguide film that have higher stiffness than other portions of the cured waveguide film.

26. The apparatus according to claim 21, wherein, The cutting assembly includes at least one of the following: Die-cutting machine Milling machine, Waterjet cutting machine Ultrasonic cutting machine, or Laser cutting machine.

27. An apparatus for forming a waveguide portion, comprising: First mold part; Second mold part; Radiation source; as well as Cut components; The device is configured as follows: A photocurable material is received in the space between a first mold portion and a second mold portion opposite to the first mold portion. The photocurable material is irradiated with radiation suitable for photocuring by the radiation source to form a cured waveguide film. The cutting assembly is used to cut portions of the cured waveguide film to produce cut portions separated from the cured waveguide film. The cut portion is annealed to provide the waveguide portion. The waveguide portion has a higher stiffness than the solidified waveguide film.

28. The apparatus according to claim 27, wherein, The apparatus is configured to anneal the cut portion by irradiating it with radiation suitable for photocuring the photocurable material using the radiation source.

29. The apparatus of claim 27, further comprising a heat source, in, The device is configured to anneal the cut portion by heating it with the heat source.

30. The apparatus according to claim 27, wherein, The device is also configured to: The cutting assembly is used to cut multiple portions of the cured waveguide film to produce multiple cut portions. The plurality of cut sections are annealed to provide a plurality of waveguide sections.

31. The apparatus according to claim 27, wherein, The cutting assembly includes at least one of the following: Die-cutting machine Milling machine, Waterjet cutting machine Ultrasonic cutting machine, or Laser cutting machine.

32. An apparatus for forming a waveguide portion, comprising: First mold part; Second mold part; A frame disposed between the first mold portion and the second mold portion, wherein the frame has a first rigidity, and wherein the frame defines a hole; Radiation source; and Cut components; The device is configured as follows: Photocurable material is received in the holes of the frame. The photocurable material is irradiated with radiation suitable for photocuring using the radiation source to form a cured waveguide film having a second stiffness different from the first stiffness. Using the cutting assembly, waveguide portions are cut from the cured waveguide film by means of a cutting path along the frame, the path at least partially surrounding the aperture. The waveguide portion, comprising the cured photocurable material, is extracted from the frame along the path.

33. The apparatus according to claim 32, wherein, The frame defines one or more additional holes.

34. The apparatus according to claim 33, wherein, The device is configured to receive the photocurable material in each of the holes in the frame.

35. The apparatus according to claim 34, wherein, The device is configured to simultaneously irradiate the photocurable material in each of the holes with the radiation.

36. The apparatus according to claim 32, wherein, The first stiffness is greater than the second stiffness.

37. The apparatus according to claim 32, wherein, The cutting assembly includes at least one of the following: Die-cutting machine Milling machine, Waterjet cutting machine Ultrasonic cutting machine, or Laser cutting machine.

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