Energized ophthalmic lens

Description of equivalent WO 2010033679 A2

ENERGIZED OPHTHALMIC LENS

0002RELATED PATENT APPLICATIONS This application claims priority to Provisional Patent Application U.S. Ser. No.

000361/192,765 which was filed on September 22, 2008, the contents of which are relied upon and incorporated by reference.

FIELD OF USE

0005This invention describes an energized biomedical device and, more specifically, in some embodiments, an energized ophthalmic lens.

BACKGROUND

0007Traditionally an ophthalmic device, such as a contact lens, an intraocular lens or a punctal plug included a biocompatible device with a corrective, cosmetic or therapeutic quality. A contact lens, for example, can provide one or more of: vision correcting functionality; cosmetic enhancement; and therapeutic effects. Each function is provided by a physical characteristic of the lens. A design incorporating a refractive quality into a lens can provide a vision corrective function. A pigment incorporated into the lens can provide a cosmetic enhancement. An active agent incorporated into a lens can provide a therapeutic functionality. Such physical characteristics are accomplished without the lens entering into an energized state.

0008More recently, it has been theorized that active components may be incorporated into a contact lens. Some components can include semiconductor devices. Some examples have shown semiconductor devices embedded in a contact lens placed upon animal eyes. However, such devices lack a free standing energizing mechanism. Although wires may be run from a lens to a battery to power such semiconductor devices, and it has been theorized that the devices may be wirelessly powered, no mechanism for such wireless power has been available.

0009It is desirable therefore to have ophthalmic lenses that are energized to an extent suitable for providing one or more of functionality into an ophthalmic lens and a controlled change in optical characteristic of an ophthalmic lens or other biomedical device.

SUMMARY

0011Accordingly, the present invention includes an ophthalmic lens, with an energy source incorporated therein. In some embodiments, the energy source provides an energized state that is capable of powering a semiconductor device. Some embodiments can also include a cast molded silicone hydrogel contact lens with a battery or other energy source contained within the ophthalmic lens in a biocompatible fashion. The energized portion is thereby created via inclusion of a battery into the lens. Accordingly, the present invention includes a disclosure of an energized ophthalmic lens with an energy source embedded into the ophthalmic lens formed from a reactive monomer mix. The energy source is placed within a cast molding system prior to polymerization of a reactive mixture also contained within the mold system. Lenses are formed via the control of actinic radiation to which the reactive monomer mixture is exposed.

0012DESCRIPTION OF THE DRAWINGS Fig. 1 illustrates an exemplary embodiment of an energized ophthalmic lens.

0013Fig. 2 illustrates an exemplary embodiment of an energized ophthalmic lens including a device for reenergization. Fig. 3 illustrates an example of an energized ophthalmic lens with a device for reenergization and an energized component.

0014Fig. 4 illustrates an example of an energized ophthalmic lens in cross section. Fig. 5 illustrates exemplary design shapes for energy sources.

0015Fig. 6 illustrates a depiction of some exemplary types of energy sources ordered by estimates of the amount of energy that they may provide in ratio to their volume.

0016Fig. 7 illustrates a processor that may be sued to implement some aspects of the present invention.

0017DETAILED DESCRIPTION OF THE INVENTION The present invention includes biomedical devices, such as ophthalmic lenses and in particular, the present invention includes an ophthalmic lens with an Energy Source incorporated therein. The description of both preferred and alternative embodiments are exemplary embodiments only, and it is understood that to those skilled in the art that variations, modifications and alterations may be apparent. It is therefore to be understood that said exemplary embodiments do not limit the scope of the underlying invention.

GLOSSARY

0019In this description and claims directed to the presented invention, various terms may be used for which the following definitions will apply:

0020Energized: The state of being able to ripply electrical emrt-Ttt to or to have electrical energy stored within. Energized Ophthalmic Lens: An energized ophthalmic lens refers to an ophthalmic lens with an energy source added onto or embedded within the formed lens.

0021Energy: The capacity of a physical system to perform work. Many uses within this invention may relate to said capacity being able to perform electrical actions in doing work.

0022Energy Source: A device capable of supplying Energy or placing a biomedical device in an Energized state.

0023Energy Harvesters: A device capable of extracting energy from the environment and convert it to electrical energy.

0024Lens: As used herein "lens" refers to any ophthalmic device that resides in or on the eye. These devices can provide optical correction or may be cosmetic. For example, the term lens can refer to a contact lens, intraocular lens, overlay lens, ocular insert, optical insert or other similar device through which vision is corrected or modified, or through which eye physiology is cosmetically enhanced (e.g. iris color) without impeding vision. In some embodiments, the preferred lenses of the invention are soft contact lenses are made from silicone elastomers or hydrogels, which include but are not limited to silicone hydrogels. Lens Forming Mixture: As used herein, the term "lens forming mixture" or "Reactive

0025Mixture" or "RMM"(reactive monomer mixture) refers to a monomer or prepolymer material which can be cured and crosslinked or crosslinked to form an ophthalmic lens. Various embodiments can include lens forming mixtures with one or more additives such as: UV blockers, tints, photoinitiators or catalysts, and other additives one might desire in an ophthalmic lenses such as, contact or intraocular lenses.

0026Lithium Ion Cell: An electrochemical cell where Lithium ions move through the cell to generate electrical energy. This electrochemical cell, typically called a battery, may be reenergized or recharged in its typical forms.

0027Power: Work done or energy transferred per unit of time. Rechargeable or Re-energizable: Capable of being restored to a state with higher capacity to do work. Many uses within this invention may relate to the capability of being restored with the ability to flow electrical current at a certain rate for a certain, reestablished time period. Reenergize or Recharge: To restore to a state with higher capacity to do work. Many uses within this invention may relate to restoring a device to the capability to flow electrical current at a certain rate for a certain, reestablished time period.

0028In general, in the present invention, an Energy Source is embodied within an ophthalmic lens. In some embodiments, an ophthalmic device includes an optic zone through which a wearer of the lens sees. A pattern of components and an Energy Source can be located exterior to an optic zone. Other embodiments can include a pattern of conductive material and one or more Energy Sources which are small enough to not adversely affect the sight of a contact lens wearer and therefore can be located within, or exterior to, an optical zone.

0029In general, according to some embodiments of the present invention, an Energy Source is embodied within an ophthalmic lens

0030Energized Ophthalmic Lens Device

0031Referring now to Fig, 1, an energized lens 100 with an embedded Energy Source 140 is illustrated. In this example, a standard hydrogel formed ophthalmic lens is depicted as item 110. Embedded within the formed hydrogel material 110 is an Energy Source 140. In some embodiments, this Energy Source 140 includes an electrochemical cell or battery as the storage means for the energy. Such a storage means may require effective means of encapsulation and isolation of the materials it is made from and the environment as illustrated by a sealed encapsulating layer 130. Some specific embodiments include a lithium ion battery. Lithium ion batteries are generally rechargeable. According to the present invention, the lithium ion battery is in electrical communication with a charging device and also a power management circuit, both of which are embedded within the lens.

0032Additionally, some embodiments may include a battery acting as an Energy Source 140 that is made of thin layers of materials. Such embodiments may therefore also include a flexible substrate to provide support for the thin film material 120. Numerous embodiments include various Energy Sources 140 and types, wherein each of the Energy Sources 140 Energize an ophthalmic lens.

0033Referring now to Fig. 6, a view of some of the options that may be included in different types of Energy Sources 140 that may be embedded in an energized ophthalmic lens 100 is demonstrated in Fig. 6 as item 600. As previously mentioned, a set of embodiments of Energy Sources 140 can include batteries. Batteries are demonstrated in Fig. 6 as item 620. Fig. 6 also demonstrates a graph of the various options in order of the density of the energy that they can store. Batteries 600, for example, include a region of energy density from ~50 to -800 Whr/L.

0034Referring now to graph 600 it can be seen that energy harvesters, item 640 do not exhibit high energy density. However, it may be apparent to one skilled in the art that there are other manners that energy harvesters embedded within a lens would have an advantage.

0035For example, energy harvesters can include photovoltaic energy cells, thermoelectric cells or piezoelectric cells. Such harvesters have a positive aspect in that they can absorb energy from the environment and then can provide electrical energy without a wired connection. In some embodiments, harvesters may comprise the source in an energized ophthalmic lens. In other embodiments, however, the energy harvester may be combined with other sources that can store energy in an electrical form.

0036Other types of Energy Source include the use of capacitor type devices, as shown in graph 600 as item 630. It may be apparent, that capacitors comprise an energy density solution that is higher than energy harvesters but less than that of batteries, item 620. Capacitors, nevertheless, have some inherent advantages.

0037Capacitors are a type of Energy Source that stores the energy in an electrical form and therefore, may be one of the Energy Sources combined with energy harvesters to create a wireless Energy Source that is capable of storage of energy. Generally capacitors have an advantage over batteries in that they have higher power density, in general, than batteries.

0038Capacitors that may be embedded in a silicone lens according to the present invention include: electrical thin film capacitors, Mylar capacitors, electrolytic capacitors and relative newer and more advanced technologies of high density nanoscale capacitors or supercapacitors. In some additional embodiments, Energy Sources including electrochemical cells or batteries 620 may define a relatively desirable operational point. Batteries embedded within a silicone or other hydrogel have numerous advantageous characteristics. For example, Batteries store energy in a form that is directly converted to electrical energy. Some batteries may be rechargeable or Re-en ergizable and therefore, represent another category of Energy Source that may be coupled to energy harvesters. Batteries useful for the present invention will have relatively high energy density, the energy the batteries store can perform functions with reasonable energy requirements. In addition, in some embodiments, the batteries can be assembled into forms that are flexible. For applications requiring higher power capabilities, it may be apparent to one skilled in the art that a battery may also be coupled to capacitors. There may be numerous embodiments that comprise a battery at least as part of an Energy Source in an energized ophthalmic lens.

0039In additional embodiments a fuel cell is included as an Energy Source 610. Fuel cells generate electricity by consuming a chemical fuel source which then generates electricity and byproducts including heat energy. Fuel cell embodiments may be possible using biologically available materials as the fuel source.

0040The following discussions of the embodiments of this invention may focus generally on using a battery as the principle Energy Source of an energized ophthalmic lens. This focus should not limit the scope of the inventive art, as numerous Energy Sources including those that have been discussed may comprise embodiments of an energized ophthalmic lens.

0041As mentioned in some embodiments of the present invention the Energy Source includes an electrochemical cell or battery. There are many different types of batteries which may be included in embodiments of energized ophthalmic lenses. For example, single use batteries may be formed from various cathode and anode materials. By way of non-limiting examples these materials may include Zinc, carbon, Silver, Manganese, Cobalt, Lithium,

0042Silicon. Still other embodiments may derive from the use of batteries that are rechargeable. Such batteries may in turn be made of Lithium Ion technology; Silver technology, Magnesium technology, Niobium technology. It may be apparent to one skilled in the art that various current battery technologies for single use or rechargeable battery systems may comprise the Energy Source in various embodiments of an energized ophthalmic lens.

0043The physical and dimensional constraints of a contact lens environment may favor certain battery types over others. An example of such favorability may occur for thin film batteries. Thin film batteries may occupy the small volume of space consistent with human ophthalmic embodiments. Furthermore, they may be formed upon a substrate that is flexible allowing for the body of both the ophthalmic lens and included battery with substrate to have freedom to flex.

0044In the case of thin film batteries, examples may include single charge and rechargeable forms. Rechargeable batteries afford the ability of extended usable product lifetime and, therefore, higher energy consumption rates. Much development activity has focused on the technology to produce electrically energized ophthalmic lenses with rechargeable thin film batteries; however, the inventive art is not limited to this subclass.

0045Rechargeable thin film batteries are commercially available, for example, Oak Ridge National Laboratory has produced various forms since the early 1990s. Current commercial producers of such batteries include Excellatron Solid State, LLC (Atlanta, GA), Infinite Power Solutions (Littleton, CO), and Cymbet Corporation, (Elk River, MN). The technology is currently dominated by uses that include flat thin film batteries. Use of such batteries may comprise some embodiments of this inventive art; however, forming the thin film battery into a three dimensional shape, for example with a spherical radius of curvature comprises desirable embodiments of the inventive art. It may be clear to one skilled in the art that numerous shapes and forms of such a three dimensional battery embodiment are within the scope of the invention.

0046In Figs. 5a, 5b, 5c and 5d are numerous examples of different shapes that an Energy Source in an ophthalmic lens may take. Item 500 shows a reference Energy Source made of thin film materials, which for reference is formed as a flat shape. When the dimension of such a shape 500 is approximately a millimeter or less, it may comprise an Energy Source for an energized ophthalmic lens. Item 510 shows an exemplary three dimensional form where the flexible substrate and encapsulated battery assume a full annular shape, which when not flexibly distorted is roughly the same shape that an undistorted ophthalmic lens may assume. In some embodiments, the radius of the annular shape may approximate eight millimeters for an energized ophthalmic lens embodiment. The same three-dimensional aspect may be shared by embodiments which are quarter annulus 530, half annulus 520 or other arcuate shape. It may be apparent to one skilled in the arts that many different shapes including other partial annular shapes may comprise alternative embodiments within the scope of this invention. In some embodiments, rectangular, planar shapes may also be fit into a semi-spherical shell geometry included in an ophthalmic lens.

0047Another set of embodiments of the present invention relate to specific battery chemistries which may be advantageously utilized in an energized ophthalmic lens. An example embodiment, which was developed by Oak Ridge Laboratories, comprises constituents of a Lithium or Lithium-Ion Cell. Common materials for the anode of such cells include Lithium metal or alternatively for the Lithium Ion Cell include graphite. An example alternative embodiment of these cells includes be the incorporation of micro-scaled silicon features to act as the anode of such a thin film battery incorporated into a contact lens.

0048The materials used for the cathode of the batteries used in this novel art as well include multiple materials options. Common cathode materials include Lithium Manganese Oxide and Lithium Cobalt Oxide which have good performance metrics for the batteries thus formed.

0049Alternatively, Lithium Iron Phosphide cathodes, can have similar performance, however, may in some applications have improved aspects relating to charging. As well, the dimension of these and other cathode materials can improve charging performance; as for example, forming the cathode from nano-scaled crystals of the various materials can dramatically improve the rate that the battery may be recharged at. Various materials that may be included as constituents of an Energy Source may be preferably encapsulated. It may be desirable to encapsulate the Energy Source to generally isolate its constituents from entering the ophthalmic environment. Alternatively, aspects of the ophthalmic environment may negatively affect the performance of Energy Sources if they are not properly isolated by an encapsulation embodiment. Various embodiments of the inventive art may derive from the choice of materials.

0050Accordingly, in some embodiments, a lens material can include a silicone containing component. A "silicone-containing component" is one that contains at least one [-Si-O-] unit in a monomer, macromer or prepolymer. Preferably, the total Si and attached O are present in the silicone-containing component in an amount greater than about 20 weight percent, and more preferably greater than 30 weight percent of the total molecular weight of the silicone- containing component. Useful silicone-containing components preferably comprise polymerizable functional groups such as acrylate, methacrylate, acrylamide, methacrylamide, vinyl, N-vinyl lactam, N-vinylamide, and styryl functional groups. Suitable silicone containing components include compounds of Formula I

0051<img file="WO2010033679A2_D0001.tif" /> where

0052R¹ is independently selected from monovalent reactive groups, monovalent alkyl groups, or monovalent aryl groups, any of the foregoing which may further comprise functionality selected from hydroxy, amino, oxa, carboxy, alkyl carboxy, alkoxy, amido, carbamate, carbonate, halogen or combinations thereof; and monovalent siloxane chains comprising 1-100 Si-O repeat units which may further comprise functionality selected from alkyl, hydroxy, amino, oxa, carboxy, alkyl carboxy, alkoxy, amido, carbamate, halogen or combinations thereof; where b = O to 500, where it is understood that when b is other than 0, b is a distribution having a mode equal to a stated value; wherein at least one R¹ comprises a monovalent reactive group, and in some embodiments between one and 3 R¹ comprise monovalent reactive groups. As used herein "monovalent reactive groups" are groups that can undergo free radical and/or cationic polymerization. Non-limiting examples of free radical reactive groups include (meth)acrylates, styryls, vinyls, vinyl ethers, Ci_₆alkyl(meth)acrylates, (meth)acrylamides, Ci.₆alkyl(meth)acrylamides, N-vinyllactams, N-vinylamides, C₂-i₂alkenyls, C₂-i₂alkenylphenyls, C₂-i₂alkenylnaphthyls, C₂-₆alkenylphenylCi_₆alkyls, O-vinylcarbamates and O-vinylcarbonates. Non-limiting examples of cationic reactive groups include vinyl ethers or epoxide groups and mixtures thereof. In one embodiment the free radical reactive groups comprises (meth)acrylate, acryloxy, (meth)acrylamide, and mixtures thereof.

0053Suitable monovalent alkyl and aryl groups include unsubstituted monovalent Ci to Ci₆alkyl groups, C₆-Ci₄ aryl groups, such as substituted and unsubstituted methyl, ethyl, propyl, butyl, 2-hydroxypropyl, propoxypropyl, polyethyleneoxypropyl, combinations thereof and the like.

0054In one embodiment b is zero, one R¹ is a monovalent reactive group, and at least 3 R¹ are selected from monovalent alkyl groups having one to 16 carbon atoms, and in another embodiment from monovalent alkyl groups having one to 6 carbon atoms. Non-limiting examples of silicone components of this embodiment include 2-methyl-,2-hydroxy-3-[3- [l,3,3,3-tetramethyl-l-[(trimethylsilyl)oxy]disiloxanyl]propoxy]propyl ester ("SiGMA"),

00552-hydroxy-3-methacryloxypropyloxypropyl-tris(trimethylsiloxy)silane, 3-methacryloxypropyltris(trimethylsiloxy)silane ("TRIS"), 3-methacryloxypropylbis(trimethylsiloxy)methylsilane and 3-methacryloxypropylpentamethyl disiloxane. In another embodiment, b is 2 to 20, 3 to 15 or in some embodiments 3 to 10; at least one terminal R¹ comprises a monovalent reactive group and the remaining R¹ are selected from monovalent alkyl groups having 1 to 16 carbon atoms, and in another embodiment from monovalent alkyl groups having 1 to 6 carbon atoms. In yet another embodiment, b is 3 to 15, one terminal R¹ comprises a monovalent reactive group, the other terminal R¹ comprises a monovalent alkyl group having 1 to 6 carbon atoms and the remaining R¹ comprise monovalent alkyl group having 1 to 3 carbon atoms. Non-limiting examples of silicone components of this embodiment include (mono-(2-hydroxy-3-methacryloxypropyl)-propyl ether terminated polydimethylsiloxane (400-1000 MW)) ("OH-mPDMS"), monomethacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxanes (800- 1000 MW), ("mPDMS").

0056In another embodiment b is 5 to 400 or from 10 to 300, both terminal R¹ comprise monovalent reactive groups and the remaining R¹ are independently selected from monovalent alkyl groups having 1 to 18 carbon atoms which may have ether linkages between carbon atoms and may further comprise halogen. In one embodiment, where a silicone hydrogel lens is desired, the lens of the present invention will be made from a reactive mixture comprising at least about 20 and preferably between about 20 and 70%wt silicone containing components based on total weight of reactive monomer components from which the polymer is made. In another embodiment, one to four R¹ comprises a vinyl carbonate or carbamate of the formula:

0057Formula II

0058<img file="WO2010033679A2_D0002.tif" />

0059wherein: Y denotes O-, S- or NH-; R denotes, hydrogen or methyl; d is 1, 2, 3 or 4; and q is 0 or 1.

0060The silicone-containing vinyl carbonate or vinyl carbamate monomers specifically include: l,3-bis[4-(vinyloxycarbonyloxy)but-l-yl]tetramethyl-disiloxane; 3- (vinyloxycarbonylthio) propyl-[tris (trimethylsiloxy)silane]; 3-[tris(trimethylsiloxy)silyl] propyl allyl carbamate; 3-[tris(trimethylsiloxy)silyl] propyl vinyl carbamate; trimethylsilylethyl vinyl carbonate; trimethylsilylmethyl vinyl carbonate, and

0061<img file="WO2010033679A2_D0003.tif" />

0062Where biomedical devices with modulus below about 200 are desired, only one R¹ shall comprise a monovalent reactive group and no more than two of the remaining R¹ groups will comprise monovalent siloxane groups.

0063Another class of silicone-containing components includes polyurethane macromers of the following formulae:

0064Formulae IV-VI

0065(*D*A*D*G)_α *D*D*E¹; E(*D*G*D*A)_α *D*G*D*E¹ or; E(*D*A*D*G)_α *D*A*D*E^! wherein: D denotes an alkyl diradical, an alkyl cycloalkyl diradical, a cycloalkyl diradical, an aryl diradical or an alkylaryl diradical having 6 to 30 carbon atoms,

0066G denotes an alkyl diradical, a cycloalkyl diradical, an alkyl cycloalkyl diradical, an aryl diradical or an alkylaryl diradical having 1 to 40 carbon atoms and which may contain ether, thio or amine linkages in the main chain;

0067* denotes a urethane or ureido linkage; a is at least 1 ;

0068A denotes a divalent polymeric radical of formula:

0069Formula VII

0070<img file="WO2010033679A2_D0004.tif" />

0071R¹¹ independently denotes an alkyl or fluoro-substituted alkyl group having 1 to 10 carbon atoms which may contain ether linkages between carbon atoms; y is at least 1; and p provides a moiety weight of 400 to 10,000; each of E and E¹ independently denotes a polymerizable unsaturated organic radical represented by formula: Formula VIII

0072R12 R13CH=C-(CH₂)w-(X)χ— (Z)_z— (Ar)y-Ri4 — wherein: R¹² is hydrogen or methyl; R¹³ is hydrogen, an alkyl radical having 1 to 6 carbon atoms, or a — CO — Y — R¹⁵ radical wherein Y is — O — ,Y — S — or — NH — ; R¹⁴ is a divalent radical having 1 to 12 carbon atoms; X denotes — CO — or — OCO — ; Z denotes — O — or — NH — ; Ar denotes an aromatic radical having 6 to 30 carbon atoms; w is 0 to 6; x is 0 or 1 ; y is 0 or 1 ; and z is 0 or 1.

0073A preferred silicone-containing component is a polyurethane macromer represented by the following formula:

0074Formula IX

0075<img file="WO2010033679A2_D0005.tif" /> wherein R¹⁶ is a diradical of a disocyanate after removal of the isocyanate group, such as the diradical of isophorone diisocyanate. Another suitable silicone containing macromer is compound of formula X (in which x + y is a number in the range of 10 to 30) formed by the reaction of fluoroether, hydroxy -terminated polydimethylsiloxane, isophorone diisocyanate and isocyanatoethylmethacrylate.

0076Formula X

0077<img file="WO2010033679A2_D0006.tif" />

0078Other silicone containing components suitable for use in this invention include macromers containing polysiloxane, polyalkylene ether, diisocyanate, polyfluorinated hydrocarbon, polyfluorinated ether and polysaccharide groups; polysiloxanes with a polar fluorinated graft or side group having a hydrogen atom attached to a terminal difluoro- substituted carbon atom; hydrophilic siloxanyl methacrylates containing ether and siloxanyl linkanges and crosslinkable monomers containing polyether and polysiloxanyl groups. Any of the foregoing polysiloxanes can also be used as the silicone containing component in this invention.

0079In some embodiments, a binding layer can be utilized to position an Energy Source within a mold part used to form an ophthalmic lens. The binding polymer can be capable of forming an interpenetrating polymer network with a lens material, the need for formation of covalent bonds between the binder and lens material to form a stable lens is eliminated. Stability of a lens with an Energy Source placed into the binder is provided by entrapment of the Energy Source in the binding polymer and the lens base polymer. The binding polymers of the invention can include, for example, those made from a homopolymer or copolymer, or combinations thereof, having similar solubility parameters to each other and the binding polymer has similar solubility parameters to the lens material. Binding polymers may contain functional groups that render the polymers and copolymers of the binding polymer capable of interactions with each other. The functional groups can include groups of one polymer or copolymer interact with that of another in a manner that increases the density of the interactions helping to inhibit the mobility of and/or entrap the pigment particles. The interactions between the functional groups may be polar, dispersive, or of a charge transfer complex nature. The functional groups may be located on the polymer or copolymer backbones or be pendant from the backbones.

0080By way of non-limiting example, a monomer, or mixture of monomers, that form a polymer with a positive charge may be used in conjunction with a monomer or monomers that form a polymer with a negative charge to form the binding polymer. As a more specific example, methacrylic acid ("MAA") and 2-hydroxyethylmethacrylate ("HEMA") may be used to provide a MAA/HEMA copolymer that is then mixed with a HEMA/3-(N, N-dimethyl) propyl acrylamide copolymer to form the binding polymer.

0081As another example, the binding polymer may be composed of hydrophobically- modified monomers including, without limitation, amides and esters of the formula:

0082CH₃(CH₂ )_X-L-COCHR=CH₂ wherein L may be -NH or oxygen, x may be a whole number from 2 to 24, R may be a Ci to Cβ alkyl or hydrogen and preferably is methyl or hydrogen. Examples of such amides and esters include, without limitation, lauryl methacrylamide, and hexyl methacrylate. As yet another example, polymers of aliphatic chain extended carbamates and ureas may be used to form the binding polymer.

0083Binding polymers suitable for a binding layer may also include a random block copolymer of HEMA, MAA and lauryl methacrylate ("LMA"), a random block copolymer of HEMA and MAA or HEMA and LMA, or a homopolymer of HEMA. The weight percentages, based on the total weight of the binding polymer, of each component in these embodiments is about 93 to about 100 weight percent HEMA, about 0 to about 2 weight percent MAA, and about 0 to about 5 weight percent LMA.

0084The molecular weight of the binding polymer can be such that it is somewhat soluble in the lens material and swells in it. The lens material diffuses into the binding polymer and is polymerized and/or cross-linked. However, at the same time, the molecular weight of the binding polymer cannot be so high as to impact the quality of the printed image. Preferably, the molecular weight of the binding polymer is about 7,000 to about 100,000, more preferably about 7,000 to about 40,000, most preferably about 17,000 to about 35,000 M_peak which corresponds to the molecular weight of the highest peak in the SEC analyses ( = (M_n x M_w) ²) For purposes of the invention, the molecular weight can be determined using a gel permeation chromatograph with a 90° light scattering and refractive index detectors. Two columns of PW4000 and PW2500, a methanol-water eluent of 75/25 wt/wt adjusted to 5OmM sodium chloride and a mixture of polyethylene glycol and polyethylene oxide molecules with well defined molecular weights ranging from 325,000 to 194 are used. One ordinarily skilled in the art will recognize that, by using chain transfer agents in the production of the binding polymer, by using large amounts of initiator, by using living polymerization, by selection of appropriate monomer and initiator concentrations, by selection of amounts and types of solvent, or combinations thereof, the desired binding polymer molecular weight may be obtained. Preferably, a chain transfer agent is used in conjunction with an initiator, or more preferably with an initiator and one or more solvents to achieve the desired molecular weight. Alternatively, small amounts of very high molecular weight binding polymer may be used in conjunction with large amounts of solvent to maintain a desired viscosity for the binding polymer. Preferably, the viscosity of the binding polymer will be about 4,000 to about 15,000 centipoise at 23° C.

0085Chain transfer agents useful in forming the binding polymers used in the invention have chain transfer constants values of greater than about 0.01, preferably greater than about 7, and more preferably greater than about 25,000.

0086Any desirable initiators may be used including, without limitation, ultra-violet, visible light, thermal initiators and the like and combinations thereof. Preferably, a thermal initiator is used, more preferably 2,2-azobis isobutyronitrile and 2,2-azobis 2-methylbutyronitrile. The amount of initiator used will be about 0.1 to about 5 weight percent based on the total weight of the formulation. Preferably, 2,2-azobis 2-methylbutyronitrile is used with dodecanethiol.

0087A binding polymer layer or other media may be made by any convenient polymerization process including, without limitation, radical chain polymerization, step polymerization, emulsion polymerization, ionic chain polymerization, ring opening, group transfer polymerization, atom transfer polymerization, and the like. Preferably, a thermal- initiated, free- radical polymerization is used. Conditions for carrying out the polymerization are within the knowledge of one ordinarily skilled in the art. Solvents useful in the production of the binding polymer are medium boiling solvents having boiling points between about 120 and 230 ° C. Selection of the solvent to be used will be based on the type of binding polymer to be produced and its molecular weight. Suitable solvents include, without limitation, diacetone alcohol, cyclohexanone, isopropyl lactate, 3- methoxy 1-butanol, l-ethoxy-2-propanol, and the like. In some embodiments, a binding polymer layer 111 of the invention may be tailored, in terms of expansion factor in water, to the lens material with which it will be used. Matching, or substantially matching, the expansion factor of the binding polymer with that of the cured lens material in packing solution may facilitate the avoidance of development of stresses within the lens that result in poor optics and lens parameter shifts. Additionally, the binding polymer can be swellable in the lens material, permitting swelling of the image printed using the colorant of the invention. Due to this swelling, the image becomes entrapped within the lens material without any impact on lens comfort.

0088In some embodiments, colorants may be included in the binding layer. Pigments useful with the binding polymer in the colorants of the invention are those organic or inorganic pigments suitable for use in contact lenses, or combinations of such pigments. The opacity may be controlled by varying the concentration of the pigment and opacifying agent used, with higher amounts yielding greater opacity. Illustrative organic pigments include, without limitation, pthalocyanine blue, pthalocyanine green, carbazole violet, vat orange # 1 , and the like and combinations thereof. Examples of useful inorganic pigments include, without limitation, iron oxide black, iron oxide brown, iron oxide yellow, iron oxide red, titanium dioxide, and the like, and combinations thereof. In addition to these pigments, soluble and non-soluble dyes may be used including, without limitation, dichlorotriazine and vinyl sulfone- based dyes. Useful dyes and pigments are commercially available.

0089Colors may be arranged for example in a pattern to mask components present in a lens according to the present invention. For example, opaque colors can simulate the appearance of a natural eye and cover up the presence of components within a lens.

0090In addition, in some embodiments, the binding layer contains one or more solvents that aid in coating of the binding layer onto the mold part. It is another discovery of the invention that, to facilitate a binding layer that does not bleed or run on the mold part surface to which it is applied, it is desirable, and preferred, that the binding layer have a surface tension below about 27 mN/m. This surface tension may be achieved by treatment of the surface, for example a mold surface, to which the binding layer will be applied. Surface treatments may be effected by methods known in the art, such as, but not limited to plasma and corona treatments. Alternatively, and preferably, the desired surface tension may be achieved by the choice of solvents used in the colorant.

0091Accordingly, exemplary solvents useful in the binding layer include those solvents that are capable of increasing or decreasing the viscosity of the binding layer and aiding in controlling the surface tension. Suitable solvents include, without limitation, cyclopentanones, 4-methyl-2-pentanone, l-methoxy-2-propanol, 1 -ethoxy-2-propanol, isopropyl lactate and the like and combinations thereof. Preferably, 1 -ethoxy-2-propanol and isopropyl lactate are used.

0092In some preferred embodiments, at least three different solvents are used in the binding layer material of the invention. The first two of these solvents, both medium boiling point solvents, are used in the production of the binding polymer. Although these solvents may be stripped from the binding polymer after its formation, it is preferred that they are retained. Preferably, the two solvents are 1 -ethoxy-2-propanol and isopropyl lactate. An additional low boiling solvent, meaning a solvent the boiling point of which is between about 75 and about 120° C, can be used to decrease the viscosity of the colorant as desired. Suitable low boiling solvents include, without limitation, 2- propanol, 1 -methoxy-2-propanol, 1-propanol, and the like and combinations thereof. Preferably, 1-propanol is used. The specific amount of solvents used can depend on a number of factors. For example, the amount of solvents used in forming the binding polymer will depend upon the molecular weight of the binding polymer desired and the constituents, such as the monomers and copolymers, used in the binding polymer. The amount of low boiling solvent used will depend upon the viscosity and surface tension desired for the colorant. Further, if the colorant is to be applied to a mold and cured with a lens material, the amount of solvent used will depend upon the lens and mold materials used and whether the mold material has undergone any surface treatment to increase its wettability. Determination of the precise amount of solvent to be used is within the skill of one ordinarily skilled in the art. Generally, the total weight of the solvents used will be about 40 to about 75 weight percent of solvent will be used. In addition to the solvents, a plasticizer may be and, preferably is, added to the binding layer to reduce cracking during the drying of the binding layer and to enhance the diffusion and swelling of the binding layer by the lens material. The type and amount of plasticizer used will depend on the molecular weight of the binding polymer used and, for colorants placed onto molds that are stored prior to use, the shelf-life stability desired. Useful plasticizers include, without limitation, glycerol, propylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol 200, 400, or 600, and the like and combinations thereof. Preferably, glycerol is used. Amounts of plasticizer used generally will be 0 to about 10 weight percent based on the weight of the colorant.

0093One ordinarily skilled in the art will recognize that additives other than those discussed also may be included in the binding layer composition of the invention. Suitable additives include, without limitation, additives that aid flow and leveling, additives for foam prevention, additives for rheology modification, and the like, and combinations thereof.

0094In some embodiments of the present invention, the binding layer becomes embedded in the lens material upon curing of the lens material. Thus, the binding layer may embed closer to the front or back surface of the lens formed depending on the surface of the mold to which the lens the binding layer is applied. Additionally, one or more layers of binding layer may be applied in any order.

0095Although invention may be used to provide hard or soft contact lenses made of any known lens material, or material suitable for manufacturing such lenses, preferably, the lenses of the invention are soft contact lenses having water contents of about 0 to about 90 percent. More preferably, the lenses are made of monomers containing hydroxy groups, carboxyl groups, or both or be made from silicone-containing polymers, such as siloxanes, hydrogels, silicone hydrogels, and combinations thereof. Material useful for forming the lenses of the invention may be made by reacting blends of macromers, monomers, and combinations thereof along with additives such as polymerization initiators. Suitable materials include, without limitation, silicone hydrogels made from silicone macromers and hydrophilic monomers.

0096Additional embodiments may come from the nature in which the internal components are encapsulated by the encapsulating material. It may be possible to coat an Energy Source in a manner that involves a seam between two layers of encapsulant. Alternatively the encapsulant may be applied in such a manner to not generate seams, although it should be noted that many embodiments require the Energy Source to provide two distinct and isolated electrical contact points. It may be obvious to one skilled in the art that there are various other means to encapsulate an Energy Source which may be consistent with the art detailed herein.

0097As mentioned, an Energy Source in some embodiments may need to provide energy in an electrical form and therefore have at least two electrically isolated contact points to connect the Energy Source to an element that is being energized. In some embodiments two electrically conductive bonding pads may be cut or otherwise formed into the encapsulant. To these bond pads electrical conduits of some form may be affixed to allow the electrical energy to flow from the source to the device to be energized. Referring now to Fig. 2, item 200 demonstrates how an Energy Source 210 may have two contact points 240. These contact points may have two electrically conductive wires 230 affixed to them to conduct the energy from the Energy Source 210 to another device 220.

0098The manner by which the electrical wires 230 may be connected to the contact points 240 may form numerous embodiments within this art. In some embodiments, these wires may be affixed by a wire bonding technique which will physically scrub a wire into an electrical contact with an alternative bond pad metal. Still other embodiments may derive from melting a contacting metallurgy between the wire 230 and the contact point 240 for example with a solder technique. It may be possible in other embodiments to evaporatively deposit the connecting wires 230 to the contact point 240. In still other embodiments, conductive epoxies or inks may be used to define the conducting element 230 and to connect it to the contact pad 240. It may be obvious to one skilled in the art that numerous means of making a connection to the contact point of an Energy Source to convey energy to or from another device may comprise embodiments within the scope of this invention.

0099As previously discussed and demonstrated in Fig. 2, item 200, the Energy Source may be defined as a composite of two or more of the types of Energy Sources that have been described. For example, the Energy Source in Fig. 2 may be comprised of a rechargeable lithium ion thin film battery 210 that is combined with a photocell 240. Numerous photocell types may be consistent with the art herein, as an example a photovoltaic device that is used for such embodiments is the CPC 1822 manufactured by Clare, Inc. (Beverly, MA), which measures approximately 2.5 mm x 1.8 mm x 0.3 mm in die form and is capable of providing 4 volts of direct current electricity (VDC) in light conditions. In some embodiments, the output of the photovoltaic device may be directly provided to the battery as demonstrated in Fig. 2. Alternatively, a power management device may control the charging of the rechargeable battery with a reenergizing device of some kind. This specific example is provided in a non- limiting sense as there may be numerous embodiments of reenergizing an Energy Source within the scope of this inventive art on energized ophthalmic lenses.

0100In the case of the Clare photovoltaic cell, an external light source may comprise the manner to reenergize another attached Energy Source. In light intensities on the order of one sun or more, the cell provides significant charging current. There may be numerous manners to configure a reenergizing system to interact with such a photovoltaic device. By nonlimiting example, it may be possible to provide light of appropriate intensity during the storage of an ophthalmic lens in hydration media.

0101Other embodiments of reenergizing an Energy Source may be defined by alternative devices. For example, a thermal gradient across the ophthalmic lens body may be used by a thermoelectric device to provide reenergization to an Energy Source. In alternative embodiments, external energy may be coupled into the ophthalmic lens with use of an external radiofrequency signal and an absorbing device in the lens; an external voltage field and a capacitive coupling device in the lens; or mechanical energy or pressure and a piezoelectric device. It may be obvious to one skilled in the art that there may be numerous manners of reenergizing an Energy Source in an energized ophthalmic lens.

0102As mentioned in the earlier discussion, non-rechargeable chemistries of battery type Energy Sources may provide alternative embodiments of the novelty disclosed herein. While potentially lacking some of the advantages of rechargeability, such embodiments may alternatively have potential cost and implementation advantages. It may be considered within the scope of this disclosure to include non-rechargeable encapsulated electrochemical cells in equivalent manners to the rechargeable Energy Sources that have been disclosed herein.

0103The various Energy Sources of the present invention provide an "on board" power source within the ophthalmic lens which may be used in conjunction with electronic components, flexible circuit interconnect substrates, printed electrical interconnects, sensors, and/or other custom active components. These various components that may be energized may define embodiments that perform a broad range of functions. By way of non-limiting examples, an energized ophthalmic lens may be an electro-optic device energizing functionality to adjust the focal characteristics of an ophthalmic lens. In still other embodiments, the energized function may activate a pumping mechanism within the ophthalmic lens that may pump pharmaceuticals or other materials. Still further energized function may involve sensing devices and communication devices within an ophthalmic lens. It may be obvious to one skill in the art that there are an abundant range of embodiments relating to the function that may be enabled within an energized ophthalmic lens.

0104In some embodiments the Energy Source within an energized ophthalmic lens may energize a control function within the ophthalmic lens to provide for the wireless, controlled activation of still further energized function within an ophthalmic lens or other shaped hydrogel article. By way of non-limiting example, the Energy Source may comprise an embedded encapsulated thin film microbattery which may have a finite, limited maximum current capacity. In order to minimize leakage currents, or quiescent current draw so that a fully charged thin film microbattery will maintain its charge as long as possible during storage, various means to activate or electrically connect the microbattery to other components within the electroactive lens may be utilized. In some embodiments, a photovoltaic cell (e.g. Clare CPCl 822 in die form) or a photoelectric sensing device may activate transistors or other microelectronic components within the lens under prescribed lighting conditions that are then activate the interconnection of the battery with other microelectronic components within the lens. In another embodiment, a micro-sized hall-effect sensor/switch such as the Al 172 manufactured by Allegro Microsystems, Inc. (Worcester, MA) may be used to activate the battery and/or other microelectronic components within the lens when exposed to a north and/or south pole of a magnet. In other embodiments, physical contact switches, membrane switches, RF switches, temperature sensors, photodiodes, photoresistors, phototransistors, or optical sensors may be used to activate the battery and/or attached electronics within the energized ophthalmic lens.

0105In some embodiments an Energy Source within an energized ophthalmic lens may be incorporated alongside integrated circuits. In exemplary embodiments of this type, incorporation of planar thin film microbatteries on silicon substrates are incorporated into the semiconductor fabrication process. Such approaches may provide separate power sources for various integrated circuits which may be incorporated into the electroactive lens of the present invention. In alternative embodiments the integrate circuit may be incorporated as a distinct component of the energized lens. Referring to Fig. 3, item 300 a depiction of an exemplary embodiment of an energized ophthalmic lens is shown. In this depiction, the Energy Source 310 may include a thin film, rechargeable lithium ion battery. The battery may have contact points 370 to allow for interconnection. Wires may be wire bond wires to the contact points 370 and connect the battery to a photoelectric cell 360 which may be used to reenergize the battery Energy Source 310. Additional wires may connect the Energy Source to a flexible circuit interconnect via wire bonded contacts on a second set of contact points 350. These contact points 350 may be a portion of a flexible interconnect substrate 355. This interconnect substrate may be formed into a shape approximating a typical lens form in a similar manner to the Energy Source previously discussed. To add additional flexibility, an interconnect substrate 355 may include additional shape features such as radial cuts 345 along its length. On individual flaps of the interconnect substrate 355 may be connected various electronic components like ICs, discrete components, passive components and such devices which are shown as item 330. These components are interconnected by wires or other connection means 340 to the conduction paths within the interconnect substrate 355. By way of non-limiting example, the various components may be connected to the flexible interconnect substrate 355 by the various means that interconnections to the battery already discussed may be made. The combination of the various electrical components may define a control signal for an electro-optical device shown as item 390. This control signal may be conducted along interconnect 320. This type of exemplary energized ophthalmic lens with energized function is provided only for the purpose of example. In no way should this description be construed to limit the scope of the inventive art as it may be apparent to one skilled in the arts that many different embodiments of function, design, interconnection scheme, energization scheme and overall utilization of the concepts of this invention may exist. It may provide further exemplary descriptive purposes to consider how the example described in relation to Fig. 3 appears in a cross sectional representation. Such a cross section along the line in Fig. 3 shown as item 380 is depicted in Fig. 4 item 400. This depiction focuses on a cross section where the Energy Source device may be a thin film battery device. The cross section shows the general body of the ophthalmic lens, 440. Within that body 440 is the thin film battery with a substrate upon which it is built 420. Proceeding up from the substrate there may be a cathode layer 422 which may be surrounded by an electrolyte layer 423 which then may be coated by an anode layer 424. These layers may be surrounded by an encapsulating layer 421 that seals the battery layers from the external environment. In one exemplary embodiment the electronically controlled optic device may be shown as item 410. As mentioned above these descriptions are made in a non-limiting sense and many alternative embodiments of an energized and functional ophthalmic lenses may be apparent to those skilled in the art.

0106In some embodiments there may be manners of affecting the ophthalmic lens' appearance. Aesthetics of the thin film microbattery surface may be altered in various manners which demonstrate a particular appearance when embedded in the electroactive contact lens or shaped hydrogel article. In some embodiments the thin film microbattery may be produced with aesthetically pleasing patterned and/or colored packaging materials which serves to either give a muted appearance of the thin film microbattery or alternatively provide iris-like colored patterns, solid and/or mixed color patterns, reflective designs, iridescent designs, metallic designs, or potentially any other artistic design or pattern. In other embodiments, the thin film battery may be partially obscured by other components within the lens, for example a photovoltaic chip mounted to the battery anterior surface, or alternatively placement of the battery behind all or a portion of a flexible circuit. In further embodiments, the thin film battery may be strategically located such that either the upper or lower eyelid partially or wholly obscures the visibility of the battery. It may be apparent to one skilled in the art that there are numerous embodiments relating to appearance of an energized ophthalmic device and the methods to define them.

0107There may be numerous embodiments relating to the method of forming an energized ophthalmic device of the various types that have been described. In one set of embodiments, the inventive art herein may include assembling subcomponents of a particular energized ophthalmic lens embodiment in separate steps. The "off-line" assembly of advantageously shaped thin film microbatteries, flexible circuits, interconnects, microelectronic components, and/or other electroactive components in conjunction with a biocompatible, inert, conformal coating to provide an all-inclusive, embeddable singular package that can be incorporated into known cast molding contact lens manufacturing processes. Flexible circuits may include those fabricated from copper clad polyimide film or other similar substrates.

0108Conformal coatings may include, but are not limited to, parylene (grades N, C, D, HT, and any combinations thereof), poly(p-xylylene), dielectric coatings, silicone conformal coatings, polyurethane conformal coatings, acrylic conformal coatings, rigid gas permeable polymers, or any other advantageous biocompatible coatings.

0109Some embodiments of the present invention include methods that are directed toward the geometric design of thin film microbatteries in geometries amenable to the embedment within and/or encapsulation by ophthalmic lens materials. Other embodiments include methods for incorporating thin film microbatteries in various materials such as, but not limited to, hydrogels, silicone hydrogels, rigid gas-permeable "RGP" contact lens materials, silicones, thermoplastic polymers, thermoplastic elastomers, thermosetting polymers, conformal dielectric/insulating coatings, and hermetic barrier coatings.

0110Still other embodiments involve methods for the strategic placement of an Energy Source within an ophthalmic lens geometry. Specifically, in some embodiments the Energy Source may be an opaque article. Since the Energy Source may not obstruct the transmission of light through the ophthalmic lens, methods of design in some embodiments may ensure that the central 5-8 mm of the contact lens may not be obstructed by any opaque portions of the Energy Source. It may be apparent to one skilled in the art that there may be many different embodiments relating to the design of various Energy Sources to interact favorably with the optically relevant portions of the ophthalmic lens.

0111In some embodiments the mass and density of the Energy Source may facilitate designs such that said Energy Source may also function either alone or in conjunction with other lens stabilization zones designed into the body of the ophthalmic lens to rotationally stabilize the lens while on eye. Such embodiments are advantageous for a number of applications including, but not limited to, correction of astigmatism, improved on-eye comfort, or consistent/controlled location of other components within the energized ophthalmic lens.

0112In additional embodiments, the Energy Source may be placed a certain distance from the outer edge of the contact lens to enable advantageous design of the contact lens edge profile in order to provide good comfort while minimizing occurrence of adverse events. Examples of such adverse events to be avoided may include superior epithelial arcuate lesions or giant papillary conjunctivitis.

0113By way of non-limiting example in some embodiments, a cathode, electrolyte and anode features of embedded electrochemical cells may be formed by printed appropriate inks in shapes to define such cathode, electrolyte and anode regions. It may be apparent that batteries thus formed include both single use cells, based for example on manganese oxide and zinc chemistries, and rechargeable thin batteries based on lithium chemistry similar to the above mentioned thin film battery chemistry. It may be apparent to one skilled in the arts that a variety of different embodiments of the various features and methods of forming energized ophthalmic lenses may involve the use of printing techniques. There may be numerous embodiments relating to apparatus that may be used to form energized ophthalmic lens embodiments with the various methods that have been discussed. A fundamental step in the processing may relate to supporting the various components comprising an ophthalmic lens Energy Source while the body of the ophthalmic lens is molded around these components. In some embodiments the Energy Source may affixed to holding points in a lens mold. The holding points may be affixed with polymerized material of the same type that will be formed into the lens body. It may be apparent to one skilled in the art, that numerous manners of supporting the various Energy Sources before they are encapsulated into the lens body comprise embodiments within the scope of this invention.

0114Referring now to Fig. 7 a controller 700 is illustrated that may be used in some embodiments of the present invention. The controller 700 includes a processor 710, which may include one or more processor components coupled to a communication device 720. In some embodiments, a controller 700 can be used to transmit energy to the energy receptor placed in the ophthalmic lens.

0115The controller can include a one or more processors, coupled to a communication device configured to communicate energy via a communication channel. The communication device may be used to electronically control one or more of: the transfer of energy to the ophthalmic lens receptor and the transfer of digital data to and from an ophthalmic lens.

0116The communication device 720 may be used to communicate, for example, with one or more controller apparatus or manufacturing equipment components, such as for example ink jet printing apparatus for ink jetting conductive material or depositing a binder layer; and a pad printing device for depositing one or more binder layers.

0117The processor 710 is also in communication with a storage device 730. The storage device 730 may comprise any appropriate information storage device, including combinations of magnetic storage devices (e.g., magnetic tape and hard disk drives), optical storage devices, and/or semiconductor memory devices such as Random Access Memory (RAM) devices and Read Only Memory (ROM) devices.

0118The storage device 730 can store a program 740 for controlling the processor 710. The processor 710 performs instructions of the program 740, and thereby operates in accordance with the present invention. For example, the processor 710 may receive information descriptive of energy receptor placement, processing device placement, and the like. The storage device 730 can also store ophthalmic related data in one or more databases. The database may include customized energy receptor designs, metrology data, and specific control sequences for ink jetting conductive material to form an energy receptor.

0119In some embodiments, an ophthalmic lens with a component, such as processor device can be matched with a Energizing Source incorporated into an ophthalmic lens and used to perform logical functions or otherwise process data within the ophthalmic lens.

0120Conclusion

0121The present invention, as described above and as further defined by the claims below, provides methods of processing ophthalmic lenses and apparatus for implementing such methods, as well as ophthalmic lenses formed thereby.