How to encapsulate microstructured lenses with PIPC

Abstract

A method of forming an optical lens includes providing a first mold insert of a molding device having a contact surface including a plurality of inverted microstructures disposed on the contact surface, each microstructure of the plurality of inverted microstructures having a shape that is inversely related to a shape of a microstructure on a surface of a molded base lens; exchanging the first mold insert with a second mold insert having a contact surface of the second mold insert; applying a curable coating to the surface of the base lens having the microstructures formed thereon; pressing the contact surface of the second mold insert against at least a portion of the curable coating applied to the surface of the base lens; and curing the curable coating into a curable layer, wherein the microstructures are substantially completely encapsulated within the curable layer.

Description

[Technical field]

[0001] The present disclosure relates to a method for encapsulating microstructures on the surface of a lens during injection molding. [Background technology]

[0002] The background discussion provided herein is intended to provide a general background to the present disclosure, and the inventors' work to the extent described in this Background section, and aspects of the description that may not have been admitted as prior art at the time of filing, are not expressly or implicitly admitted as prior art to the present invention.

[0003] Coating microstructured lenses can result in deviations from the original microlens design and may require several conceptual loops to arrive at the design correction for each coating. This in turn may require longer development time and higher costs. Furthermore, some microstructured lenses, such as Pi-Fresnel, may not be coated by common methods such as dip coating or spin coating because the optical design would be lost.

[0004] Aspects of the present disclosure may address some of the above-mentioned shortcomings in the art, particularly with the solutions set forth in the claims. Summary of the Invention [Means for solving the problem]

[0005] The present disclosure relates to a method for forming an optical lens, comprising: providing a first mold insert of a molding device having a contact surface, the contact surface including a plurality of inverted microstructures arranged on the contact surface, each microstructure of the plurality of inverted microstructures having a shape that is inversely related to a shape of a microstructure on a surface of a molded base lens; exchanging the first mold insert with a second mold insert having a contact surface of the second mold insert; applying a curable coating to the surface of the base lens on which the microstructures are formed; pressing the contact surface of the second mold insert against at least a portion of the curable coating applied to the surface of the base lens; and curing the curable coating into a curable layer, the microstructures being substantially completely encapsulated within the curable layer. The present disclosure relates to a method for forming an optical lens, as disclosed in claim 1. Advantageous aspects of the method according to the present disclosure are disclosed in claims 2 to 13. The present disclosure further relates to an optical element obtained according to the method of the present invention, the optical element of the present invention being an ophthalmic lens.

[0006] The present disclosure further relates to a molding device including a first mold insert on a first mold side, the first mold insert including a contact surface, the contact surface having a plurality of inverted microstructures formed thereon, a second mold insert on a second mold side, and a mold insert exchange mechanism including a third mold insert having a smooth contact surface, the mold insert exchange mechanism being configured to exchange the first mold insert with the third mold insert on the first mold side. The present disclosure further relates to a molding device as disclosed in claim 15.

[0007] Please note that this Summary section does not identify every feature and / or incrementally novel aspect of the present disclosure or the claimed invention. Instead, this Summary provides only a preliminary description of different embodiments and corresponding points of novelty. For additional details of the present embodiments and / or possible developments, please refer to the Detailed Description section and corresponding figures of the present disclosure as further discussed below.

[0008] Various embodiments of the present disclosure, given by way of example only, will now be described in detail with reference to the following figures, in which: [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a PIPC method for producing lenses with encapsulated microstructures useful within the scope of the present disclosure. [Diagram 2] 1 is an exemplary flow chart of a method of forming an ophthalmic lens useful within the scope of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The following disclosure provides many different variations or examples for implementing different features of the provided subject matter. To make the disclosure easier to understand, specific examples of elements and arrangements are described below. It should be understood that these are merely examples and are not intended to limit the invention or to be inoperable together in any permutation. Unless otherwise indicated, the features and embodiments described herein can be operated together in any permutation. For example, forming a first feature above or on a second feature in the following description may include an embodiment in which the first feature and the second feature are formed in direct contact with each other, and may also include an embodiment in which an additional feature may be formed between the first feature and the second feature such that the first feature and the second feature may not be in direct contact with each other. The disclosure may also repeat reference numbers and / or letters in various examples. This repetition is for the purpose of brevity and clarity and does not in itself refer to a relationship between the various embodiments and / or configurations discussed. Additionally, spatially relative terms, such as "top," "bottom," "lower," "below," "lower," "upper," "above," and the like, may be used herein to facilitate describing the relationship of one element or feature to another element or feature, as illustrated. The spatially relative terms are intended to encompass different orientations of the device during use or operation in addition to the orientation shown in the figures. Devices of the invention may be oriented in different ways (rotated 90 degrees or at other orientations) and therefore the spatially relative descriptors used herein can be interpreted similarly.

[0011] The order of discussion of different steps described herein is presented for purposes of clarity. In general, these steps can be performed in any suitable order. Also, although different features, techniques, configurations, etc. herein may each be discussed in different parts of this disclosure, it is intended that each concept can be practiced independently of each other or in combination with each other. Thus, the disclosure can be embodied and realized in many different ways.

[0012] As previously mentioned, it may be necessary to provide a microstructured lens that can be coated in the same manner as a normal lens with a smooth surface, without affecting the design of the added microstructures. For that purpose, a post-injection press coating (PIPC) process may be used.

[0013] As described herein, the PIPC process is used to encapsulate microstructures on the surface of a lens during injection molding. In particular, the PIPC process is combined with the exchange of a mold insert, such as a concave insert, between the lens injection step and the coating application step.

[0014] The PIPC process is an in-mold coating method that involves injection molding a lens, then opening the mold to apply a coating or curable material on the recently formed base lens surface, and closing the mold again to form the applied coating or curable material into a new coating on the formed base lens. In effect, the new coating adheres onto the surface of the base lens. Parameters such as pressure, temperature, and holding time can be adjusted based on the properties of the coating or curable material applied onto the recently formed base lens. In particular, the surface of the mold insert proximal to the surface of the base lens can be smooth, thus resulting in a smooth base lens. Using this same smooth mold insert to form the smooth surface of the base lens can result in the subsequently formed layer of applied coating also having a smooth surface. Thus, a method is described herein that uses PIPC to provide an expansion of molding options to allow for microstructured surface processing of the base lens and encapsulation of the microstructured surface during lens manufacturing.

[0015] 1 is a schematic diagram of a PIPC method for producing lenses with encapsulated microstructures useful within the scope of the present disclosure. In a useful range, a molding device can include a first mold side 101 and a second mold side 102, a first mold insert 198 disposed on the first mold side 101, and a second mold insert 199 disposed on the second mold side 102. The first mold side 101 and the second mold side 102 can each include a hollow portion within which the first mold insert 198 and the second mold insert 199 can be removably disposed. The first mold insert 198 can include a contact surface 105, which is disposed proximal to the second mold side 102. The contact surface 105 can have an overall shape that is flat or curved (as shown), or can take any other shape desired to form the overall shape of the microstructures. The contact surface 105 may include a plurality of inverted microstructures that are complementary in shape to the microstructures 130 on the resulting molded base lens 125 to form the microstructures 130 during molding. The second mold insert 199 may have a smooth surface or may similarly include another contact surface 105 with a plurality of inverted microstructures.

[0016] A first mold side 101 having a first mold insert 198 and a second mold side 102 having a second mold insert 199 can be configured to move towards each other to form a cavity or away from each other to open the molding device.

[0017] The cavity may be connected to a hollow line formed by the joining of the first mold side 101 and the second mold side 102. The line may be configured to receive the polymer melt 120, for example, via a screw feeder or similar polymer injection device. The polymer injector may be attached to the molding device and configured to inject the polymer melt 120 into the cavity when the first mold side 101 is joined with the second mold side 102, and form a base lens 125 having a microstructure 130 from the polymer melt 120 based on the contact surface 105 and the surface of the second mold insert 199 facing the cavity. The molding device may remain closed for a first predetermined length of time until the base lens 125 is formed. For a semi-finished lens, the curvature along the convex side of the lens is fixed, and the concave side of the base lens 125 may be modified after molding, for example, by grinding and polishing. It should be noted that the injection of polymer melt 120 from the injection source can fill multiple mold devices with one injection, and multiple lines can be connected to receive the polymer melt 120 to enable parallel production of multiple lenses.

[0018] To the extent useful, the base lens material may be selected from the group consisting of polycarbonates, isosorbide polycarbonates, thermoplastic polyurethanes, polyacrylates, polyesters, copolyesters, polymethacrylates, polystyrenes, polyamides, polysulfones, polyphenylsulfones, polyetherimides, polypentenes, polyolefins, ionomers, ethylene methacrylic acid, cyclic olefin copolymers, acrylonitrile, styrene maleic anhydride, copolymers thereof, and derivatives or mixtures thereof.

[0019] To the extent that it is useful, the base lens 125 may be further molded to form a hardenable layer 145 for encapsulating the microstructures 130. After the base lens 125 is cooled and the molding device is opened, the first mold insert 198 may be removed and replaced with a third mold insert 197. The third mold insert 197 may include a contact surface 105a, which may be smooth. It may be understood that the contact surface 105a may also be microstructured to form another layer of microstructures (in which case a fourth mold insert (not shown) may be smooth to provide an outermost layer). To the extent that it is useful, the first mold insert 198 may be replaced by removing the first mold insert 198 from the first mold side 101 and installing the third mold insert 197 in the previous position of the first mold insert 198. To a useful extent, the mold device may include a mold insert exchange mechanism that holds multiple mold inserts and allows inserts to be quickly replaced without the need for an operator to remove and unseat the mold insert. The exchange mechanism may further automatically position the replaced mold insert a desired distance away from the second mold insert 199 to achieve a desired thickness of the curable layer 145 (see below). For example, the exchange mechanism may include a rotating drum of mold inserts that can rotate the mold inserts into the first mold side 101. To a useful extent, the mold device may include a third mold side (not shown) to which a third mold insert 197 is attached to replace the entire first mold side 101 and first mold insert 198. For example, a rotary or cube mold may be used.

[0020] The curable coating 140 may be applied over the microstructured surface of the base lens 125 or over the microstructures 130 before the mold device is closed again and the curable coating 140 is spread over the microstructures 130. In particular, in both the first and second molding cycles, the first mold insert 198, the second mold insert 199, and the third mold insert 197 may be heated to promote viscous flow of the polymer melt 120 into the cavity and fill the mold insert features. Furthermore, in the second molding cycle, the amount of curable coating 140 applied may be based on the feature size of the microstructures 130. For example, if the microstructures 130 have deep crevices and high structures, more curable coating 140 may be applied to fill additional volume, such as voids. Additionally, the gap or distance between the microstructures 130 and the surface of the third mold insert 197 may further determine the amount of curable coating 140 applied to achieve the desired thickness of the resulting curable layer 145. In a useful range, the surface temperature of the base lens 125 along with the microstructures 130 can be reached before the curable coating 140 is applied. As previously described, the first molding cycle can include heating the first mold insert 198 and the second mold insert 199 to a first predetermined temperature to mold the base lens 125 based on the properties of the polymer melt 120. In the second molding cycle, the third mold insert 197 and the second mold insert 199 can be heated to a second predetermined temperature, and the curable coating 140 can be applied to the base lens 125 having a desired surface temperature before the molding device is closed again to spread, mold, and cure the curable coating 140. Of course, these parameters can be based on the properties of the curable coating 140. After the molding device remains closed for a second predetermined length of time, the molding device can be opened to remove the coated lens 150 in which the base lens 125 with the microstructures 130 is encapsulated with the curable layer 145.

[0021] In the useful range, the curable coating 140 can be an acrylate-based material. For example, the curable coating 140 can be a monofunctional (meth)acrylate, a difunctional meth(acrylate), a polyester acrylate oligomer, an epoxy modified bisphenol A epoxy, or an aliphatic urethane diacrylate. In particular, the curable coating 140 can further include one or more of a photochromic dye, a blue cut dye, a near infrared (NIR) cut dye, a UV cut dye, or other light filters. Based on the refractive index of the curable coating 140, the base lens 125, and any dye additives, the optical properties of the coated lens 150 can be tailored. A predetermined difference or delta in refractive index between the materials of the curable coating 140 and the base lens 125, and a predetermined thickness of the curable coating 140 can be tailored to preserve the optical function of the microlens (microstructure 130). For example, the refractive index of the curable coating 140 can be less than the refractive index of the base lens 125 , or the refractive index of the curable coating 140 can be greater than the refractive index of the base lens 125 .

[0022] The multiple inverse microstructures can be used to mold, for example, refractive microstructures or diffractive micro / nanostructures. The multiple inverse microstructures can be the inverse of the desired final pattern formed on the resulting lens after molding. The multiple inverse microstructures can include microlenses or microlenslets, or any other type of structure or element with a physical Z deformation / height or depth of 0.1 μm to 50 μm and a width / length of 0.5 μm to 2.0 mm. These structures preferably have a periodic or quasi-periodic layout, but may also have a random position. Preferred layouts of the microstructures are a grid with a constant grid step, a honeycomb layout, multiple concentric rings, continuous, e.g., no space between the microstructures. These structures can provide optical wavefront modification in intensity, curvature, or optical deviation, where the wavefront intensity is configured such that the structures can be absorptive and locally absorb the wavefront intensity in the range of 0% to 100%, the curvature is configured such that the structures can locally modify the wavefront curvature in the range of + / -20 diopters, and the optical deviation is configured such that the structures can locally scatter the light at angles in the range of + / -1° to + / -30°. The distance between the structures can range from 0 (adjacent) to 3 times the "X" and / or "Y" size structures (separate microstructures).

[0023] In the sense of the present disclosure, two optical elements arranged on a surface of a lens substrate are adjacent if there is a path supported by said surface linking the two optical elements and if the base surface on which the optical elements are arranged is not reached along said path. According to another range, optical elements are adjacent on the pupil if the optical lens on the pupil does not include a refractive area having a refractive power based on the prescription for said eye of the wearer or a refractive area having a refractive power based on the prescription for said eye of the wearer that is composed of a plurality of independent islands. According to another range, two optical elements are adjacent if, in the case of a path linking the two optical elements, it is not possible to measure the refractive power based on the prescription for the eye of the wearer along a portion of said path. According to another range, adjacent optical elements can also be defined in a superficial or surface-directed manner. 3mm 2 ~10mm 2 The measurement surface is 1 mm. 2 The density of optical elements per "W" is included. Optical elements are considered to be adjacent if, in the measurement surface, at least 95%, preferably 98%, of the surface has a different refractive power than the surface on which the optical element is located.

[0024] Furthermore, the microstructures forming the microstructured major surface of the ophthalmic lens substrate may include lenslets. The lenslets may form bumps and / or cavities (i.e., raised or recessed lenslet structures) on the major surface on which they are disposed. The contours of the lenslets may be round or polygonal, for example hexagonal. In particular, the lenslets may be microlenses. The microlenses may be spherical, toric, cylindrical, or aspheric, or any combination that creates a multi-element shape. The microlenses may have a single focus, a cylindrical power or multifocal, non-focus. The microlenses may be used to arrest the progression of myopia or hyperopia. In that case, the base lens substrate includes a base lens that provides a refractive power that corrects myopia or hyperopia, and the microlenses may provide a refractive power greater than the refractive power of the base lens if the wearer has myopia, or may have a refractive power less than the refractive power of the base lens if the wearer has hyperopia, respectively. The lenslet may also be a Fresnel structure, a diffractive structure such as a microlens that defines a Fresnel structure, a permanent technological bump, or a phase-shifting element. It may also be a refractive optical element such as a microprism, and a light-dispersive optical element such as a small protrusion or cavity, or any type of element that creates irregularities on a substrate. It may also be a π-Fresnel lenslet as described in US2021109379, i.e. a Fresnel lenslet whose phase function has a π phase jump at the nominal wavelength, as opposed to a single-focus Fresnel lens whose phase jump is a multiple of 2π. Such lenslets include structures with discontinuous shapes. In other words, the shape of such structures can be described by an elevation function in terms of the distance from the base level of the main surface of the optical lens to which the lenslet belongs, which function exhibits discontinuities, or whose derivative exhibits discontinuities. In a useful range, the microstructures may be brand marks, holographic marks, metasurfaces, etc.

[0025] The lenslets may have a contour shape that can be inscribed in a circle having a diameter of 0.5 micrometers (μm) or more and 2.0 millimeters (mm) or less. The lenslets may have a height of 0.1 μm or more and 50 μm or less. The height is measured in a direction perpendicular to the major surface on which the lenslets are disposed. The lenslets may have a periodic or quasi-periodic layout, but may also have random positions. One layout of the lenslets is a grid with regular grid steps, a honeycomb layout, multiple concentric rings, continuous, e.g., no spaces between the microstructures. These structures can provide optical wavefront modification in intensity, curvature, or optical deviation, where the wavefront intensity is configured such that the structures can be absorptive and can locally absorb the wavefront intensity in the range of 0% to 100%, the curvature is configured such that the structures can locally modify the wavefront curvature in the range of + / - 20, 500, or 1000 diopters, and the optical deviation is configured such that the structures can locally scatter the light at angles in the range of + / - 1° to + / - 30°. The distance between the structures can be in the range of 0 (adjacent) to 3 times the structures (separate microstructures).

[0026] [Example] Examples 1 - In each cavity of a two cavity mold, a 6.50 based concave (CV) insert with a CV microlens on its surface was installed in the top half of the mold and a 6.10 based smooth convex (CX) insert was installed in the bottom half of the mold. Semi-finished (SF) PC lenses with a diameter of 76 mm and a center thickness of 9 mm with a CX microlens on the front surface were injection molded using the following process parameters:

[0027] [Table 1]

[0028] At the end of cooling, the mold was opened to expose the convex surface of the molded lenses. The 6.50 base microstructured CV inserts in the top half of the mold were replaced with smooth CV inserts with the same base curve. One drop or 0.15 grams of the acrylate-based coating was then dispensed into the center of each lens using a syringe. The mold was then closed again with a secondary clamping force of 150 tons (in this case the same as the primary clamping force) to spread the coating evenly across the lens surface. After 1 minute, the mold was reopened and the lenses were ejected. The microlenses on the front surface (CX) of the SF lenses were completely encapsulated by the coating, resulting in a smooth surface.

[0029] Example 2 - Using two 5.50 base concave inserts with CV microlenses on their surfaces, a 76 mm diameter and 8 mm center thickness SF PC lens with a CX microlens on the front surface was molded using the same process parameters as described in Example 1, except the shot size was 2.60 inches.

[0030] When the mold was opened after injection, the 5.50 base microstructured CV insert in the top half of the mold was replaced with a smooth 5.50 base CV insert. As in Example 1, the microlenses on the front surface of the SF lens were completely encapsulated by the coating.

[0031] In particular, advantages of the disclosed method include: i) the ability to make Transitions® Stellest™ lenses and other photochromic lenses with different μ-structures; ii) the ability to coat new myopia control lens designs (such as continuous μ-lenses and Pi-Fresnel) that could not be coated by standard methods such as dip or spin due to loss of optical design; iii) the ability to include optical filters such as blue cut in the PIPC coating; and iv) the ability to avoid the need for additional standard hard coatings for scratch resistance.

[0032] FIG. 2 is an exemplary flow chart of a method 200 of forming a lens useful within the scope of the present disclosure. In step 205, a first mold insert 198 of a molding device can be provided, the first mold insert 198 having a contact surface 105, the contact surface 105 including a plurality of inverse microstructures that are complementary in shape to the microstructures 130. In step 210, the molding device can be closed and a base lens 125 can be formed by injecting a polymer melt 120 into the cavity. In step 220, the molding device can be opened and the base lens can be cooled. The first mold insert 198 can be removed. In step 230, the first mold insert 198 is replaced with a third mold insert 197 at the first mold side 101 of the molding device. In step 240, once the surface temperature of the base lens 125 reaches a predetermined temperature, a curable coating 140 can be applied to the microstructures 130 formed on the base lens 125. In step 250, the mold device is closed again and the curable coating 140 is spread and cured at an elevated temperature to which the third mold insert 197 and the second mold insert 198 are heated. In step 260, the third mold insert 197 is separated from the second mold insert 199 and the resulting coated lens 150 can then be removed. The curable coating 140 can be cured to form a curable layer 145 that encapsulates the microstructures 130 on the surface of the base lens 125. An optical element can be made, which is an ophthalmic lens, in particular a spectacle lens.

[0033] In the above description, specific details such as the particular geometry and various components of the processing system and the processes used therein are described. However, it will be understood that the technology described herein can be implemented in other embodiments that differ from these specific details, and such details are for the purpose of explanation and not for the purpose of limitation. The embodiments disclosed herein have been described with reference to the accompanying drawings. Similarly, specific numbers, materials and configurations are described for the purpose of explanation in order to provide a detailed understanding. Nevertheless, the embodiments can be implemented without such specific details. Components having substantially the same functional structure are denoted by the same reference numerals, and therefore, any redundant description may be omitted.

[0034] To aid in understanding various embodiments, various techniques have been described as multiple separate operations. The order of description should not be construed as to imply that these operations are necessarily order dependent. In fact, these operations need not be performed in the order presented. The described operations may be performed in an order different from that specifically described, unless expressly indicated otherwise. Various additional operations may be performed and / or described operations may be omitted.

[0035] Those skilled in the art will appreciate that many variations may be made to the operation of the techniques described above while still achieving the same objectives of the present disclosure. Such variations are intended to fall within the scope of the present disclosure. Thus, the above description of the embodiments is not intended to be limiting. Rather, any limitations to the embodiments are presented in the following claims.

[0036] Embodiments of the present disclosure may be as indicated by the numbers in parentheses below.

[0037] (1) A method of forming an optical lens comprising providing a first mold insert (198) of a molding device having a contact surface (105), the contact surface (105) including a plurality of inverse microstructures disposed thereon, each microstructure of the plurality of inverse microstructures having a shape that is inversely related to a shape of a microstructure (130) on a surface of a base lens (125); and connecting the first mold insert (198) to a second mold insert (197) having a contact surface (105a) of a second mold insert (197). replacing the second mold insert (197) with a contact surface (105a) of the second mold insert (197); applying a curable coating (140) to a surface of the base lens (125) having the microstructures (130) formed thereon; pressing a contact surface (105a) of the second mold insert (197) against at least a portion of the curable coating (140) applied to the surface of the base lens (125); and curing the curable coating (140) into a curable layer (145), wherein the microstructures (130) are substantially completely encapsulated within the curable layer (145).

[0038] (2) The method of (1), further comprising forming the base lens (125) in a molding device including a first mold insert (198) having a contact surface (105).

[0039] (3) The method of either (1) or (2), wherein exchanging the first mold insert (198) further comprises opening the mold device while leaving the base lens (125) in the cavity of the mold device.

[0040] (4) The method according to any one of (1) to (3), wherein the material of the base lens (125) is selected from the group consisting of polycarbonate, isosorbide polycarbonate, thermoplastic polyurethane, polyacrylate, polyester, copolyester, polymethacrylate, polystyrene, polyamide, polysulfone, polyphenylsulfone, polyetherimide, polypentene, polyolefin, ionomer, ethylene methacrylic acid, cyclic olefin copolymer, acrylonitrile, styrene maleic anhydride, copolymers thereof, and derivatives or mixtures thereof.

[0041] (5) Any one of the methods (2) through (4), wherein the base lens (125) is formed by injection molding at an injected polymer melt temperature at least 200° F. higher than the glass transition temperature of the base lens (125).

[0042] (6) Any one of the methods (1) to (5), wherein the first mold insert (198) and the mold device are heated from 5°F below the glass transition temperature of the base lens (125) to 50°F below the glass transition temperature of the base lens (125).

[0043] (7) Any one of the methods (1) to (6), wherein applying the curable coating (140) to the surface of the base lens (125) further comprises applying the curable coating (140) to the surface of the base lens (125) when the surface temperature of the base lens (125) reaches a predetermined base lens (125) surface temperature.

[0044] (8) The method of (7), wherein the predetermined base lens (125) surface temperature is between 30°F and 300°F.

[0045] (9) The method of any one of (1) to (8), wherein the curable coating (140) further comprises a photochromic dye, a blue cut dye, a near infrared light cut dye, a UV cut dye, or other light filter.

[0046] (10) The method of any one of (1) to (9), wherein the curable coating (140) is an acrylate-based coating.

[0047] (11) The method of any one of (1) to (10), wherein the second mold insert (197) has a smooth contact surface (105a) of the second mold insert.

[0048] (12) The method of any one of (1) to (11), wherein the second mold insert (197) has a contact surface (105a) that includes a second pattern of inverse microstructures.

[0049] (13) The method of (12), further comprising repeating the steps of replacing the first mold insert (198) with a third mold insert having a patterned contact surface thereof, applying a curable coating (140) to the recently formed surface, and pressing the contact surface (105a) of the third mold insert against at least a portion of the applied curable coating (140) to form a plurality of microstructured layers on the base lens (125).

[0050] (14) An optical element obtained by any one of the methods (1) to (13), which is an ophthalmic lens.

[0051] (15) A molding device including a first mold insert (198) on a first mold side (101), the first mold insert (198) including a contact surface (105), the contact surface (105) having a plurality of inverted microstructures formed thereon, a second mold insert (199) on a second mold side (102), and a third mold insert (197) having a smooth contact surface (105a), wherein the first mold insert (198) is interchangeable with the third mold insert (197) on the first mold side (101).

[0052] (16) Any one of the methods (1) to (14), wherein the first mold insert (198) and the mold device are heated to at least 260°F and a packing pressure of at least 800 psi is applied.

[0053] (17) Any one of the methods (1) to (14), wherein the base lens (125) has a diameter of at least 50 mm and a center thickness of at least 1.0 mm, and a drop of at least 0.05 grams, or at least 0.10 grams, or more preferably at least 0.15 grams, of the curable coating (140) is applied to the center of the base lens (125).

[0054] (18) The method of (17), wherein a clamping force of 150 tons is applied while pressing the contact surface (105a) of the second mold insert (197) against at least a portion of the curable coating (140) for one minute.

[0055] (19) Any one of the methods (1) to (14), wherein replacing the first mold insert (198) with the second mold insert further comprises replacing the first mold side (101) including the first mold insert (198) with a second mold side including the second mold insert (197). [Explanation of symbols]

[0056] 101 First mold side 102 Second mold side 105 Contact surface 120 Polymer Melt 125 base lens 130 Microstructure 140 Curable Coatings 145 Curable layer 150 Lens 197 Mold Insert 198 Mold Insert 199 Mold Inserts

Claims

1. 1. A method of forming an optical lens, comprising the steps of: providing a first mold insert of a molding device having a contact surface, the contact surface including a plurality of inverse microstructures disposed on the contact surface, each microstructure of the plurality of inverse microstructures having a shape that is inversely related to a shape of a microstructure on a surface of a base lens; replacing the first mold insert with a second mold insert having a contact surface of the second mold insert; applying a curable coating to a surface of the base lens having the microstructures formed thereon; pressing the contact surface of the second mold insert against at least a portion of the curable coating applied to the surface of the base lens; curing the curable coating into a curable layer, wherein the microstructures are substantially completely encapsulated within the curable layer; and A method comprising:

2. The method of claim 1 , further comprising forming the base lens in the molding device including the first mold insert having the contact surface.

3. The method of claim 1 , wherein exchanging the first mold insert further comprises opening the mold device while leaving the base lens in a cavity of the mold device.

4. 2. The method of claim 1, wherein the material of the base lens is selected from the group consisting of polycarbonate, isosorbide polycarbonate, thermoplastic polyurethane, polyacrylate, polyester, copolyester, polymethacrylate, polystyrene, polyamide, polysulfone, polyphenylsulfone, polyetherimide, polypentene, polyolefin, ionomer, ethylene methacrylic acid, cyclic olefin copolymer, acrylonitrile, styrene maleic anhydride, copolymers thereof, and derivatives or mixtures thereof.

5. The method of claim 2 , wherein the base lens is formed by injection molding with an injected polymer melt temperature at least 200° F. above the glass transition temperature of the base lens.

6. 10. The method of claim 1, wherein the first mold insert and the mold device are heated from 5°F below the glass transition temperature of the base lens to 50°F below the glass transition temperature of the base lens.

7. 2. The method of claim 1 , wherein applying the curable coating to the surface of the base lens further comprises applying the curable coating to the surface of the base lens when a surface temperature of the base lens reaches a predetermined base lens surface temperature.

8. The method of claim 7, wherein the predetermined base lens surface temperature is between 30°F and 300°F.

9. The method of claim 1 , wherein the curable coating further comprises a photochromic dye, a blue-cut dye, a near infrared light-cut dye, a UV-cut dye, or other light filter.

10. The method of claim 1 , wherein the curable coating is an acrylate-based coating.

11. The method of claim 1 , wherein the second mold insert has a smooth contact surface of the second mold insert.

12. The method of claim 1 , wherein the second mold insert has a contact surface that includes a second pattern of inverse microstructures.

13. replacing the first mold insert with a third mold insert having a patterned contact surface of the third mold insert; applying said curable coating to the recently formed surface; pressing the contact surface of the third mold insert against at least a portion of the applied curable coating to form a plurality of microstructured layers on the base lens; The method of claim 12 , further comprising repeating:

14. An optical element obtainable according to the method of any one of claims 1 to 13, which is an ophthalmic lens.

15. a first mold insert on a first mold side, the first mold insert including a contact surface, the contact surface having a plurality of inverse microstructures formed thereon; a second mold insert on the second mold side; a third mold insert having a smooth contact surface; Including, The first mold insert is interchangeable with the third mold insert on the first mold side.

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