Patent Application
20220177348
This disclosure relates to shaped articles and methods and apparatus for forming shaped articles, and more particularly to shaped glass articles and methods and apparatus for pressing glass preforms to form shaped glass articles, as well as liquid lenses comprising shaped articles.
Isothermal glass pressing generally includes pressing a glass plate at a relatively low temperature (e.g., a temperature at which the glass has a relatively high viscosity of 1010 poise to 1012 poise) using a polished ceramic or metallic mold. Such high viscosity of the glass helps to prevent the glass from sticking to the mold and to maintain the surface quality of the finished article. The mold complexity and relatively high pressing force generally limits isothermal glass pressing to small glass articles with simple geometries (e.g., ophthalmic lenses).
Disclosed herein are shaped articles, methods and apparatus for forming shaped articles, and liquid lenses comprising shaped articles.
Disclosed herein is a shaped article comprising a substrate comprising a glass material, a glass-ceramic material, or a combination thereof and a cavity formed in the substrate, wherein a sidewall of the cavity comprises a random textured surface with a surface roughness of less than or equal to 300 nm.
Disclosed herein is a method of machining a protrusion in a graphite block comprising positioning a cutting tool adjacent the graphite block such that a rotational axis of the cutting tool is longitudinally aligned with an intended protrusion position on the graphite block. The protrusion can be formed in the graphite block by translating the cutting tool in a first longitudinal direction toward the graphite block to engage the graphite block with the cutting tool while rotating the cutting tool about the rotational axis and without translating the cutting tool in a lateral direction. The cutting tool can be translated in a second longitudinal direction away from the graphite block and without translating the cutting tool in the lateral direction to disengage the cutting tool from the graphite block.
Disclosed herein is a method of forming a shaped article comprising pressing a preform with a monolithic graphite mold comprising a mold body and a plurality of mold protrusions extending from the mold body at a pressing temperature and a pressing pressure sufficient to transform the preform into the shaped article comprising a plurality of cavities corresponding to the plurality of mold protrusions. The preform can comprise a glass material, a glass-ceramic material, or a combination thereof. The mold protrusions of the monolithic graphite mold can comprise a random textured surface.
Disclosed herein is an apparatus for pressing a plurality of cavities in a preform comprising a monolithic graphite mold comprising a mold body and a plurality of mold protrusions extending from the mold body. The mold protrusions of the monolithic graphite mold can comprise a random textured surface.
Disclosed herein is a liquid lens comprising a lens body comprising a first window, a second window, and a cavity disposed between the first window and the second window, and a first liquid and a second liquid disposed within the cavity of the lens body, the first liquid and the second liquid having different refractive indices such that an interface between the first liquid and the second liquid forms a lens. A sidewall of the cavity can comprise a random textured surface with a surface roughness of less than or equal to 300 nm.
It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description, serve to explain principles and operation of the various embodiments.
Reference will now be made in detail to exemplary embodiments which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts. The components in the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the exemplary embodiments.
Numerical values, including endpoints of ranges, can be expressed herein as approximations preceded by the term “about,” “approximately,” or the like. In such cases, other embodiments include the particular numerical values. Regardless of whether a numerical value is expressed as an approximation, two embodiments are included in this disclosure: one expressed as an approximation, and another not expressed as an approximation. It will be further understood that an endpoint of each range is significant both in relation to another endpoint, and independently of another endpoint.
As used herein, the term “average coefficient of thermal expansion,” or “average CTE,” refers to the average coefficient of linear thermal expansion of a given material between 0° C. and 300° C. As used herein, the term “coefficient of thermal expansion,” or “CTE,” refers to the average coefficient of thermal expansion unless otherwise indicated. The CTE can be determined, for example, using the procedure described in ASTM E228 “Standard Test Method for Linear Thermal Expansion of Solid Materials With a Push-Rod Dilatometer”, or for glass materials, ISO 7991:1987 “Glass—Determination of coefficient of mean linear thermal expansion.”
As used herein, the term “surface roughness” means Ra surface roughness determined as described in ISO 25178, Geometric Product Specifications (GPS)—Surface texture: areal, filtered at 25 μm.
As used herein, the term “non-stick,” when used in reference to a material from which a mold surface is formed, can mean that there is no substantial formation of an oxide layer at the interface between a substrate or preform material (e.g., a glass material, a glass-ceramic material, or a combination thereof) with the mold surface at a temperature at which the substrate material has a viscosity of 108 poise. Additionally, or alternatively, the term “non-stick,” when used in reference to a material from which a mold surface is formed, can mean that the diffusion of any component of a substrate or preform material from the interface between the substrate material with the mold surface into the mold surface at a temperature at which the substrate material has a viscosity of 108 poise is limited to a depth of 1 nm.
As used herein, the term “formed from” can mean one or more of comprises, consists essentially of, or consists of. For example, a component that is formed from a particular material can comprise the particular material, consist essentially of the particular material, or consist of the particular material.
In various embodiments, a shaped article comprises a substrate comprising a glass material, a glass-ceramic material, or a combination thereof and a cavity formed in the substrate, wherein a sidewall of the cavity comprises a random textured surface with a surface roughness of less than or equal to 300 nm. The surface topography of the random textured surface can be enabled by the mold and/or pressing process described herein.
In various embodiments, a method of machining a protrusion in a graphite block comprises positioning a cutting tool adjacent the graphite block such that a rotational axis of the cutting tool is longitudinally aligned with an intended protrusion position on the graphite block. The protrusion can be formed in the graphite block by translating the cutting tool in a first longitudinal direction toward the graphite block to engage the graphite block with the cutting tool while rotating the cutting tool about the rotational axis and without translating the cutting tool in a lateral direction. The cutting tool can be translated in a second longitudinal direction away from the graphite block and without translating the cutting tool in the lateral direction to disengage the cutting tool from the graphite block. Such longitudinal translation of the cutting tool without lateral translation during the machining can enable the smooth and/or straight sidewalls of the machined protrusion as described herein.
In various embodiments, a method of forming a shaped article comprises pressing a preform with a monolithic graphite mold comprising a mold body and a plurality of mold protrusions extending from the mold body at a pressing temperature and a pressing pressure sufficient to transform the preform into the shaped article comprising a plurality of cavities corresponding to the plurality of mold protrusions. The preform can comprise a glass material, a glass-ceramic material, or a combination thereof. The mold protrusions of the monolithic graphite mold can comprise a random textured surface. The random textured surface of the mold protrusions can be enabled by the machining process described herein. Additionally, or alternatively, the surface topography of the cavity sidewalls of the shaped article can be enabled by the random textured surface of the mold protrusions as described herein.
In various embodiments, an apparatus for pressing a plurality of cavities in a preform comprises a monolithic graphite mold comprising a mold body and a plurality of mold protrusions extending from the mold body. The mold protrusions of the monolithic graphite mold can comprise a random textured surface. The random textured surface of the mold protrusions can be enabled by the machining process described herein.
In various embodiments, a liquid lens comprises a lens body comprising a first window, a second window, and a cavity disposed between the first window and the second window, and a first liquid and a second liquid disposed within the cavity of the lens body, the first liquid and the second liquid having different refractive indices such that an interface between the first liquid and the second liquid forms a lens. A sidewall of the cavity can comprise a random textured surface with a surface roughness of less than or equal to 300 nm. The surface topography of the random textured surface can be enabled by the mold and/or pressing process described herein.
In some embodiments, apparatus 100 comprises mold 102. For example, mold 102 comprises a mold body 104 and a plurality of mold protrusions 106 extending from the mold body as shown in
In some embodiments, mold 102 (e.g., mold body 104 and/or mold protrusions 106) is formed from a non-stick and/or porous material. For example, mold 102 is formed from a graphite material. The graphite material can have properties (e.g., porosity, grain size, coefficient of thermal expansion (CTE), etc.) that enable mold 102 having beneficial characteristics for use for pressing as described herein. Potentially suitable graphite materials can include, for example, EDM 4 or AF 5 grades commercially available from Poco Graphite, Inc. (Decatur, Tex., USA).
In some embodiments, the graphite material has an open porosity of greater than 0%. For example, the graphite material has an open porosity of about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1%, about 1.5%, about 2%, about 2.5%, about 3%, about 3.5%, about 4%, about 4.5%, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, or any ranges defined by the listed values. The porosity (e.g., open and/or closed porosity) of graphite materials can be determined, for example, using mercury porosimetry. For example, mercury porosimetry measurements can be made using a mercury porosimeter (e.g., Model 915-2) commercially available from Micromeritics Instrument Corp. (Norcross, Ga., USA). The porosity can be determined, for example, using the procedure described in ASTM C709—Standard Terminology Relating to Manufactured Carbon and Graphite. The open porosity of the graphite material can help to reduce the impact of outgassing from the preform during pressing and/or enable the mold to be separated from the shaped article after pressing as described herein.
In some embodiments, the graphite material has a grain size of about 1 μm, about 2 μm, about 3 μm, about 4 μm, about 5 μm, or any ranges defined by the listed values. For example, the graphite material can be a fine grain graphite material with a relatively small grain size or average particle size. The grain size of the graphite material can be measured, for example, by scanning electron micrography (SEM), and can be reported by a manufacturer of the graphite material (e.g., based on analysis of the raw materials used to form the graphite material). The grain size of the graphite material can help to enable the mold having a low surface roughness, thereby enabling a shaped article with a corresponding low surface roughness as described herein.
In some embodiments, the graphite material has a CTE that is compatible with the preform during pressing as described herein. For example, the graphite material has a CTE within about 8×10−7/° C., within about 7×10−7/° C., within about 6×10−7/° C., within about 5×10−7/° C., within about 4×10−7/° C., within about 3×10−7/° C., within about 2×10−7/° C. of a CTE of the preform, or any ranges defined by the listed values. In some embodiments, the CTE of the graphite material is less than the CTE of the preform. In some embodiments, the CTE of the graphite material is greater than the CTE of the preform. In some embodiments, a difference between the CTE of the graphite material and the CTE of the preform is at least about 1×10−7/° C. In some embodiments, the graphite material has a CTE of about 25×10−7/° C., about 30×10−7/° C., about 35×10−7/° C., about 40×10−7/° C., about 45×10−7/° C., about 50×10−7/° C., about 55×10−7/° C., about 60×10−7/° C., about 65×10−7/° C., about 70×10−7/° C., about 75×10−7/° C., about 80×10−7/° C., about 85×10−7/° C., about 90×10−7/° C., or any ranges defined by the listed values. The graphite material with a CTE that is close to the CTE of the preform can help to prevent breakage of the preform during pressing and/or to maintain accurate positioning of the cavities formed in the preform during pressing as described herein. Additionally, or alternatively, the graphite material with a CTE that differs sufficiently from the CTE of the preform can help to enable the mold to be separated from the preform (e.g., demolding) during pressing as described herein.
Forming mold 102 from the porous material (e.g., the graphite material) can enable the mold to have a large mold surface. For example, in some embodiments, the mold surface has an area (e.g., an area defined within a perimeter of the mold surface) of about 100 cm2, about 200 cm2, about 300 cm2, about 400 cm2, about 500 cm2, about 750 cm2, about 1000 cm2, or any ranges defined by the listed values. Such a large mold surface can be difficult to manufacture using non-porous materials, which can be difficult to machine using conventional diamond tooling. Forming mold protrusions 106 using the forming process described herein can enable the mold protrusions having low surface roughness even though the mold protrusions are formed from the porous material, which typically yield machined surfaces with higher than desirable surface roughness (e.g., greater than 200 nm).
In some embodiments, mold protrusions 106 are configured as pins projecting from mold body 104. Additionally, or alternatively, mold protrusions 106 are configured to engage a preform to form a plurality of cavities corresponding to the mold protrusions as described herein. For example, mold protrusions 106, or a portion thereof, are sized and shaped to form cavities in the preform having a desired size and shape. In some embodiments, mold protrusion 106 comprises an engaging member extending away from mold body 104. In some embodiments, a size of mold protrusion 106 corresponds to a desired size of the cavities to be formed in the preform upon pressing. For example, mold protrusion 106 can have a diameter or width of about 5 mm, about 4 mm, about 3 mm, about 2 mm, about 1 mm, about 0.5 mm, or any ranges defined by the listed values. The diameter or width of mold protrusion 106 can refer to the diameter or width at a proximal end of the mold protrusion (e.g., closest to mold body 104) and/or a distal end of the mold protrusion (e.g., farthest from the mold body). Such a small mold protrusion and the resulting small cavities with smooth and/or straight sidewalls formed in the preform can be enabled by the methods and apparatus described herein. In some embodiments, mold protrusion 106 has a shape corresponding to a desired shape of the cavities to be formed in the preform upon pressing. For example, in the embodiments shown in
In some embodiments, a number of mold protrusions in the plurality of mold protrusions corresponds to a desired number of cavities in the plurality of cavities of a shaped article as described herein. For example, the number of mold protrusions 106 in the plurality of mold protrusions can be about 10, about 50, about 100, about 200, about 300, about 400, about 500, about 600, about 700, about 800, about 900, about 1000, about 1100, about 1200, about 1300, about 1400, about 1500, about 2000, or any ranges defined by the listed values. The large number of mold protrusions in the plurality of mold protrusions can be enabled by the low surface roughness of the engaging portions of the mold protrusions. For example, the low surface roughness can enable pressing a glass preform to form a shaped glass article with cavities having low surface roughness as described herein.
In some embodiments, mold protrusion 106 has a surface roughness of about 400 nm, about 300 nm, about 200 nm, about 150 nm, about 100 nm, about 50 nm, about 40 nm, about 30 nm, about 20 nm, or any ranges defined by the listed values. Such a smooth engaging surface can be enabled by machining the mold protrusion as described herein. Additionally, or alternatively, such a smooth engaging surface can enable formation of cavities with smooth sidewalls, which may be beneficial for applications such as liquid lenses as described herein.
In some embodiments, mold body 104 comprises an annular recess 114 surrounding each of the plurality of mold protrusions 106 as shown in
In some embodiments, apparatus 100 comprises a backing plate 120 as shown in
In some embodiments, backing plate 120 is formed from a porous material as described herein with reference to mold 102 (e.g., mold body 104 and/or mold protrusions 106). Backing plate 120 and mold 102 can be formed from the same or different materials.
In some embodiments, apparatus 100 comprises one or more ribs 130 disposed on the engaging surface of mold 102 (e.g., mold body 104) and/or backing plate 120. For example, in the embodiments shown in
In some embodiments, cutting tool 300 is positioned such that a rotational axis 302 of the cutting tool is longitudinally aligned with an intended protrusion position on substrate 320. Additionally, or alternatively, rotational axis 302 of cutting tool 300 can be substantially perpendicular to substrate 320 (e.g., a plane defined by the substrate and/or a surface of the substrate to be machined). In some embodiments, the intended protrusion position is the lateral position on substrate 320 at which protrusion 106 is intended to be formed (e.g., the lateral position on the substrate at which an axis of symmetry of the protrusion is to be located). The lateral position can be an X-Y position (e.g., along an X-axis perpendicular to a longitudinal or Z-axis, which can be parallel to rotational axis 302, and along a Y-axis perpendicular to each of the X-axis and the Z-axis). For example, the X-Y position can be a position within the X-Y plane defined by substrate 320.
In some embodiments, protrusion 106 is formed in substrate 320 by engaging the substrate with cutting tool 300 at step 204 as shown in
Limiting translation of cutting tool 300 to the longitudinal directions (e.g., toward and away from substrate 320) during the engaging and disengaging the cutting tool with the substrate, without translation in the lateral directions, can help to enable forming protrusion 106 with a smooth and/or straight surface as described herein. Additionally, or alternatively, limiting translation of cutting tool 300 to the longitudinal directions, without translation in the lateral directions, can help to reduce or eliminate circular features and/or facets that can be formed on a machined surface using conventional machining techniques in which a machining tool is simultaneously rotated and translated laterally. For example, circular features can include visible and/or measurable circular indentations present on a machined surface (e.g., a machined protrusion, which can have a cylindrical or frustoconical surface) that result from a non-perfect cutting or grinding operation. Such circular features can be about 20 nm to about 2 μm deep (Ra) and/or extend about 5° or about 10° to about 360° along a perimeter (e.g., a circumference) of the machined surface. Additionally, or alternatively, facets can include adjacent planar surface segments present on a machined surface (e.g., a machined protrusion, which can have a cylindrical or frustoconical surface) that can result from approximation of the intended surface shape (e.g., by X-Y circular interpolation of a computer numerical control (CNC) machine). Additionally, or alternatively, facets can result from vibration of a cutting tool (e.g., a turning tool) during machining. The machined surface of protrusion 106 formed as described herein can be a random textured surface. For example, the random textured surface can be a surface with high frequency or short term topography comprising or consisting essentially of non-repeating or coherent microfeatures, which can be indicative of machining. A random textured surface can have the relatively low surface roughness described herein. The random textured surface can be characterized, for example, using a 3D optical microscope. Additionally, or alternatively, the random textured surface can be characterized, for example, as described in ISO and/or ASME roughness computations according to ISO 4287 or ISO 4288 (e.g., for 2D roughness applications) and/or ISO 25178 (e.g., for 3D applications).
The process described above can be repeated to form additional protrusions 106 (e.g., the plurality of protrusions of mold 102). In some embodiments, cutting tool 300 is repositioned at step 208 as shown in
In some embodiments, a second protrusion 106 is formed in substrate 320 by engaging the substrate with cutting tool 300 at step 210 as shown in
In some embodiments, cutting tool 300 is disengaged from substrate 320 at step 212 as shown in
Although cutting tool 300 described in reference to
In some embodiments, negative space 310 has a shape that corresponds to a shape of protrusion 106. For example, in the embodiments shown in
In some embodiments, cutting tool 300 comprises a cutting tip 312 disposed at a distal end of the cutting tool. For example, cutting tip 312 comprises a flattened or rounded tip defining an end of cutting tool 300.
Rotation of cutting edge 308 about rotational axis 302 to form negative space 310 corresponding to the shape of protrusion 106 can enable the cutting tool to be engaged with substrate 320 to form the protrusion in the substrate with longitudinal translation of the cutting tool (e.g., without lateral translation of the cutting tool). Cutting tool 300 described herein can enable protrusion 106 having the smooth and/or straight surface described herein, thereby enabling a shaped article having a cavity with smooth and/or straight sidewalls also as described herein. For example, conventional machining techniques in which a turning tool is translated along three axes can attempt to form a curved surface using a plurality of short linear segments, thereby forming a plurality of facets that approximate the curved surface. In contrast, cutting tool 300 described herein can enable the curved surface (e.g., the engaging surface of protrusion 106) to be formed by rotating cutting edge 308 without the lateral translation that would form a plurality of facets about the curved surface.
In some embodiments, cutting edge 308 is substantially linear. Linearity can be determined, for example, by dividing the cutting edge into five sample segments, determining the highest and lowest points in each sample segment, and calculating the difference between the average highest point and the average lowest point. For example, cutting edge 308 comprises a linearity of about 0.5 μm, about 0.4 μm, about 0.3 μm, about 0.2 μm, or any ranges defined by the listed values. In some embodiments, such linearity can be enabled at least in part by the relatively small grain size of the graphite material used for the substrate as described herein.
In some embodiments, the contacting comprises contacting preform 500 with mold 102 described herein. For example, the contacting comprises bringing at least a portion of the mold surface (e.g., mold protrusions 106) into contact with first surface 502 of preform 500.
In some embodiments, method 400 comprises heating the preform at step 404 as shown in
The heating can be performed before and/or after the contacting. For example, in some embodiments, preform 500 is contacted with mold 102, and then the preform and the mold are heated together to bring the preform to the pressing temperature. In other embodiments, preform 500 is heated to an intermediate temperature (e.g., a temperature between room temperature and the pressing temperature) prior to being contacted with mold 102, and then the preform and the mold are further heated to bring the preform to the pressing temperature.
In some embodiments, method 400 comprises pressing the preform with the mold at a pressing temperature and a pressing pressure sufficient to transform the preform into a shaped article comprising a plurality of cavities corresponding to the plurality of mold protrusions at step 406 as shown in
In some embodiments, mold 102 is formed from the porous material as described herein. Such a configuration of mold 102 can enable an isothermal pressing process for producing shaped articles with high precision and/or high registration. For example, the porous material of mold 102 can help to prevent gas entrapment during pressing and/or enable venting during mold release, or demolding.
In some embodiments, pressing the preform comprises pressing the preform between the mold and a backing plate. For example, the pressing comprises pressing preform 500 between mold 102 and backing plate 120. In some embodiments, the pressing comprises maintaining preform 500 at the pressing temperature and/or maintaining the pressing force on mold 102 for a dwell time sufficient to transform the preform into the shaped article. For example, the dwell time is about 1 minute, about 5 minutes, about 10 minutes, about 20 minutes, about 30 minutes, or any ranges defined by the listed values.
In some embodiments, a number of cavities 606 in the plurality of cavities corresponds to the number of mold protrusions 106 of mold 102 as described herein. For example, the number of cavities 606 in the plurality of cavities can be about 100, about 200, about 300, about 400, about 500, about 600, about 700, about 800, about 900, about 1000, about 1100, about 1200, about 1300, about 1400, about 1500, or any ranges defined by the listed values.
In some embodiments, method 400 comprises cooling the shaped article at step 408 as shown in
In some embodiments, following the pressing and/or the cooling, shaped article 600 comprises one or more raised portions 608 disposed on one or more surfaces of the shaped article as shown in
In some embodiments, method 400 comprises polishing the shaped article at step 410 as shown in
In some embodiments, after the pressing and prior to the polishing, cavities 606 of shaped article 600 comprise blind holes as shown in
In some embodiments, the polishing does not affect the surfaces of the sidewalls of cavities 606. Thus, before and after the polishing, the sidewalls are unpolished sidewalls. In some embodiments, the sidewalls of cavities 606 of shaped article 600 have an unpolished or as-pressed surface roughness (e.g., following the pressing, the cooling, and/or the polishing) of about 120 nm, about 110 nm, about 100 nm, about 90 nm, about 80 nm, about 70 nm, about 60 nm, about 50 nm, about 40 nm, about 30 nm, about 20 nm, about 10 nm, about 5 nm, or any ranges defined by the listed values. Such a smooth surface can be enabled by the smoothness of mold protrusion 106, which can be enabled by the machining process used to form mold 102 as described herein. In some embodiments, the sidewalls of cavities 606 of shaped article 600 are substantially straight. For example, the deviation of the sidewalls of cavities 606 from linear is within +/−0.25 μm along the sidewall through a thickness of shaped article 600. In some embodiments, cavities 606 have a truncated conical shape with smooth and substantially straight sidewalls. In some embodiments, the sidewalls of cavities 606 of shaped article 600 have a random textured surface (e.g., corresponding to the random textured surface of protrusions 106 of mold 102 as described herein).
In some embodiments, a thickness of shaped article 600 (e.g., a distance between first surface 602 and second surface 604), before or after polishing, can be about 5 mm, about 4 mm, about 3 mm, about 2 mm, about 1 mm, about 0.9 mm, about 0.8 mm, about 0.7 mm, about 0.6 mm, about 0.5 mm, about 0.4 mm, about 0.3 mm, about 0.2 mm, about 0.1 mm, or any ranges defined by the listed values.
In some embodiments, method 400 comprises singulating the shaped article at step 412 as shown in
In some embodiments, the methods and apparatus described herein can be used to manufacture liquid lenses.
In some embodiments, lens body 735 of liquid lens 700 comprises a first window 741 and a second window 742. In some of such embodiments, cavity 706 is disposed between first window 741 and second window 742. In some embodiments, lens body 735 comprises a plurality of layers that cooperatively form the lens body. For example, in the embodiments shown in
In some embodiments, cavity 706 has a truncated conical shape as shown in
In some embodiments, image light enters liquid lens 700 through first window 741, is refracted at interface 740 between first liquid 738 and second liquid 739, and exits the liquid lens through second window 742. In some embodiments, cap 743 and/or base 745 comprise a sufficient transparency to enable passage of image light. For example, cap 743 and/or base 745 comprise a polymeric material, a glass material, a ceramic material, a glass-ceramic material, or a combination thereof. In some embodiments, outer surfaces of cap 743 and/or base 745 are substantially planar. Thus, even though liquid lens 700 can function as a lens (e.g., by refracting image light passing through interface 740), outer surfaces of the liquid lens can be flat as opposed to being curved like the outer surfaces of a fixed lens. In other embodiments, outer surfaces of the cap and/or the base are curved. Thus, the liquid lens comprises an integrated fixed lens. In some embodiments, shaped plate 744 comprises a glass material, a glass-ceramic material, or a combination thereof as described herein. Because image light can pass through the cavity through shaped plate 744, the shaped plate may or may not be transparent.
Although
In some embodiments, method 800 comprises bonding a base to a surface of the shaped plate. For example, method 800 comprises bonding base 745 to shaped plate 744 at step 804. The bonding comprises, for example, laser bonding, adhesive bonding, or another suitable bonding technique.
In some embodiments, method 800 comprises depositing first and second liquids into the plurality of cavities of the shaped plate. For example, method 800 comprises depositing first liquid 738 and second liquid 739 in each of the plurality of cavities 706 of shaped plate 744 at step 806.
In some embodiments, method 800 comprises bonding a cap to a surface of the shaped plate to seal the first liquid and the second liquid within the plurality of cavities and form a liquid lens array. For example, method 800 comprises bonding cap 743 to shaped plate 744 to seal first liquid 738 and second liquid 739 within the plurality of cavities 706 of the shaped plate 808. The bonding comprises, for example, laser bonding, adhesive bonding, or another suitable bonding technique.
In some embodiments, method 800 comprises singulating the liquid lens array to form a plurality of individual liquid lenses. For example, method 800 comprises singulating the liquid lens array comprising cap 743, shaped plate 744, and optionally, base 745 to form the plurality of individual liquid lenses 700 at step 810. The singulating comprises, for example, mechanical dicing, laser dicing, or another suitable dicing technique.
The methods and apparatus described herein for forming shaped articles with a plurality of cavities formed therein can enable large-scale production of shaped plates having cavities with sufficiently smooth surfaces to be used in electrowetting applications, which in turn, can enable efficient manufacturing of liquid lens arrays and/or singulated liquid lenses.
Although
In some embodiments, a shaped article comprises a plate comprising a glass material, a glass-ceramic material, or a combination thereof and a plurality of cavities formed in the plate. In some of such embodiments, an unpolished sidewall of each of the plurality of cavities has a surface roughness of less than or equal to 120 nm. Additionally, or alternatively, the plate comprises a first surface and a second surface opposite the first surface, and the first surface of the plate has an area of at least about 100 cm2. Additionally, or alternatively, each of the plurality of cavities has a truncated conical shape. Additionally, or alternatively, the sidewall of each of the plurality of cavities is substantially straight.
It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the claimed subject matter. Accordingly, the claimed subject matter is not to be restricted except in light of the attached claims and their equivalents.
This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application No. 62/831,427, filed Apr. 9, 2019, the content of which is incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2020/026333 | 4/2/2020 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62831427 | Apr 2019 | US |
