Abstract:
An apparatus ( 100 ) for cleaning contact lenses is disclosed. The apparatus comprises a housing ( 110 ) having first ( 112 ) and second ( 114 ) housing sections which are joinable to form a chamber for receiving the lens. Each of the housing sections has an operative face ( 118, 120, 124, 126 ) facing the chamber formed for receiving the lens. A reactive layer ( 122 ) is provided on a portion of each operative face and the operative faces and the reactive layers are dimensioned and arranged whereby the reactive layers come into engagement with respective surfaces of a lens ( 155 ) positioned therebetween when the first and second housing sections are joined together. A portion of at least one of the operative faces is recessed relative to the other operative face to define an open volume within the chamber when the first and second housing sections are joined together. The first and second housing sections can be constructed to be in fluid communication when the apparatus is in an opened position.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention is directed to an apparatus and method for treating contact lenses. More particularly, the invention is directed to a stand-alone apparatus and method for using same by which contact lenses can be cleaned. In a particularly advantageous form, the apparatus is single-use and disposable, and comprises a housing including a pair of closable liquid sealed containers sized and shaped to accept and retain a lens therein such that the lens is brought into contiguous wetted contact with a reactive layer during the treatment process.  
           [0002]    Contact lenses have come into wide use for correcting a wide range of vision deficiencies or cosmetic use. Typically, such lenses are formed from a thin transparent plastic material shaped and dimensioned to fit over the cornea of the eye. The lenses have an optical surface that includes a concave interior first optical surface for contact with the eye, an opposed and optically associated convex exterior second optical surface, and a surrounding edge. The two surfaces together define a corrective lens medically prescribed for a particular eye.  
           [0003]    Depending on the polymer material used to construct the lenses, the lenses may be either “hard” or “soft”. Hard contact lenses, which are comparatively more rigid, are typically formed from a relatively hydrophobic material such as polymethyl methacrylate (PMMA). Soft contact lenses, which are comparatively more pliant, are typically formed from a relatively hydrophilic polymer such as hydroxyethylmethacrylate (HEMA), which has the property of being able to absorb and bind a proportionately large amount of water within the polymer network. Soft contact lenses formed from such hydrophilic polymers, when hydrated, are more comfortable to wear than hard lenses because they conform better to the cornea of the eye and cause less irritation when worn for extended periods. For this reason, the great majority of contact lenses presently being prescribed are of the soft type.  
           [0004]    Unfortunately, soft contact lenses while being worn may collect contaminants from the eye and its environment. These contaminants, for example, may include proteins and lipids, including denatured ones, from the tear fluid of the eye, and foreign substances such as cosmetics, soaps, airborne chemicals, dust and other particulate matter. Unless periodically removed, these contaminants may cause abrasion to the surface of the eye, may impair the visual acuity of the lens, and may serve as a nutrient media for potentially harmful microorganisms.  
           [0005]    Furthermore, for wearing comfort it is necessary that soft contact lenses be maintained uniformly wetted at all times. While on the eye, the moisture content of the hydrophilic material of the lenses is maintained by tear fluid. However, when the lenses are removed for an extended period, as for cleaning or while sleeping, the lenses may dry out and become irreversibly damaged unless they are externally hydrated.  
           [0006]    Consequently, various apparatus and methods have been developed for cleaning and hydrating soft contact lenses. For example, cleaning apparatus has been provided wherein the lenses are submersed in a variety of liquid cleaning agents, such as surfactants, oxidants, disinfectants, enzymatic cleaners, or abrasives. Other cleaning apparatus has been provided which included mechanically operated or electrically powered components for vibrating, rotating, abrading, scrubbing, heating, agitating, subjecting to ultrasonic energy, or otherwise mechanically manipulating the lenses to enhance the cleaning action of the cleaning agent.  
           [0007]    Such prior apparatus and methods have not been entirely satisfactory for various reasons, including lack of cleaning effectiveness with respect to certain of the various contaminants found on the lenses, undesirable complexity, excessive time required for use, harshness to the lens material, and dependence on an external power source.  
           [0008]    One apparatus which overcomes these shortcomings is described in U.S. Pat. No. 5,657,506, the disclosure of which is incorporated by reference herein. The apparatus utilizes a two-piece lens container wherein the exposed surfaces of two sponge members, wetted with an opthalmologically compatible solution, and each having thereon a reactive layer formed of a highly porous non-abrasive relatively polymeric material such as polytetrafluoroethylene (PTFE), are brought into compressive engagement with the optical surfaces of an interposed contact lens whereby the reactive layers cause contaminants to migrate from the lens to the reactive layers. Alternate apparatus are also disclosed in U.S. Pat. No. 6,138,312, the disclosure of which is incorporated by reference herein.  
           [0009]    The present invention is directed to alternate constructions from those described in U.S. Pat. Nos. 5,657,506 and 6,138,312.  
           [0010]    Accordingly, it is a general object of the present invention to provide a new and improved apparatus for cleaning contaminated contact lenses.  
           [0011]    It is a more specific object of the invention to provide an apparatus for cleaning contaminated contact lenses which is simple to use and economical to manufacture.  
           [0012]    It is a further object of the present invention to provide a disposable single-use apparatus for cleaning contaminated contact lenses having closable liquid-sealed container within which the lenses are contained while being cleaned.  
           [0013]    It is a further object of the invention to provide a self contained apparatus for cleaning a contaminated contact lenses wherein the optical surfaces of the lenses may be received in a wetted environment in contiguous contact with a reactive medium whereby lenses can be generally cleaned without the application of abrasive force (e.g. without the force caused when rubbing the lens by hand).  
         SUMMARY OF THE INVENTION  
         [0014]    The invention is directed to an apparatus for cleaning contact lenses of the type having a pair of opposed optical surfaces, comprising a non-abrasive reactive surface operative when in contact with the optical surface of the lens to reduce contaminant matter on the lens, the reactive surface being wetable and shaped for generally contiguous engagement between the optical surface and the reactive surface. In one embodiment the apparatus comprises a housing having first and second housing sections which are joinable to form a chamber for receiving the lens. Each of the housing sections has an operative face facing the chamber formed for receiving the lens. A reactive layer is provided on a portion of each operative face and the operative faces and the reactive layers are dimensioned and arranged whereby the reactive layers come into engagement with respective optical surfaces of a lens positioned therebetween when the first and second housing sections are joined together. A portion of at least one of the operative faces is recessed relative to the other operative face to define an open volume within the chamber when the first and second housing sections are joined together. The open volume is capable of retaining an ophthalmologically compatible solution within the apparatus thereby providing a location for excess fluid to well without leaking from the apparatus. Preferably the operative faces are comprised of a compliant material and more preferably they are comprised of a compliant and absorbent material. The compliant material can take a variety of forms and, for example, can be made from fibrous cellulose material, a sponge material and/or a thin film such as a metal foil material to name a few. The first and second housing sections can be constructed to be in fluid communication when the apparatus is in an opened position to, for example, encourage drainage of fluid from one section to the other section. The apparatus can be constructed to be deformable, in whole or part, to provide a reduced volume inside the apparatus. These and other features of the invention are described in detail below. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    The invention, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:  
         [0016]    [0016]FIG. 1 is a perspective view of one embodiment of a lens cleaning apparatus in accordance with the present invention in a partially closed position.  
         [0017]    [0017]FIG. 2 is an exploded cross-sectional view of the lens cleaning apparatus of FIG. 1 in a folded over (closed) position taken along line  2 - 2  of FIG. 1  
         [0018]    [0018]FIG. 3 is a cross-sectional view of the lens cleaning apparatus of FIG. 1 taken along line  3 - 3  of FIG. 1.  
         [0019]    [0019]FIG. 4 is a cross sectional view of the lens cleaning apparatus of FIG. 1 in a closed position.  
         [0020]    [0020]FIG. 5 is a cross sectional view of another embodiment of a lens cleaning apparatus in accordance with the present invention.  
         [0021]    [0021]FIG. 6 is a cross sectional view of another embodiment of a lens cleaning apparatus in accordance with the present invention.  
         [0022]    [0022]FIG. 7 is a cross-sectional view of the lower half of another embodiment of a lens cleaning apparatus in accordance with the present invention.  
         [0023]    [0023]FIG. 8 is a cross-sectional view of the lower half of another embodiment of a lens cleaning apparatus in accordance with the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]    Referring to the figures, FIGS.  1 - 4 , show an embodiment of a lens treatment apparatus  100  in accordance with the invention and is seen to include a container  110  having an upper body section  112  and a lower body section  114 . Preferably the upper and lower body sections are joined together by hinged portion or fold line  116  which can take any suitable form. For example, hinge or fold line  116  can be a living hinge. The interior of the upper body section  112  includes convex surface portions  118  and  120 . A layer of reactive material  122  covers convex portions  118  and  120 . The interior of lower body section  114  includes concave surface portions  124  and  126 . A layer of reactive material  122  covers concave portions  124  and  126 .  
         [0025]    Convex portions  118  and  120  and concave portions  124  and  126  are generally dimensioned and positioned to cooperatively engage contact lenses  155  placed in the container  110  when the container is closed. Preferably, the interior of lower body section  114  includes a recessed portion  128  surrounding the concave portions  124  and  126  for holding an opthalmological compatible solution which solution can be prepackaged with the apparatus or placed in the apparatus prior to use. When contact lenses are placed in the apparatus for cleaning and the apparatus is closed, solution flows around the reactive layers  122  providing a fluid interface between the optical surface of the lens and the contacting surfaces of reactive layers  122 , respectively.  
         [0026]    The container body  110  can be constructed from any suitable material and can be constructed for single use or repeated use applications. For example container body  110  can be constructed from polymeric materials, including synthetic polymers such as polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate and other similar materials and can include common additives including, but not limited to, fillers, pigments and plasticizers. Container body  110  can also be constructed from natural materials such as cellulose. For example, a preferred material for container body  110  is a fibrous cellulose which is compliant and absorbent.  
         [0027]    When using an absorbent material such as fibrous cellulose for container body  110  it may be desirable to treat or coat the exterior of container body  110  to provide the container with a moisture impermeable barrier to prevent leakage of the solution from the container. For example, a wax can be applied to the exterior of an absorbent container body such as a cellulose container body to provide a moisture barrier. Alternatively, a plastic coating or metal foil can be applied to the exterior of such a container body to provide a moisture barrier. Alternatively, container body  110  can be constructed from a moisture impermeable shell such as a shell made from a synthetic polymer and an absorbent cellulose insert dimensioned to fit within such shell.  
         [0028]    Convex portions  118  and  120  and concave portions  124  and  126  can be formed directly in container body  110  or can be in the form of inserts for container body  110 . The reactive layers  122  also can be supplied in a variety of ways. For example, convex portions  118  and  120  and concave portions  124  and  126  can be made from an absorbent cellulose material and reactive layer  122  can be provided directly to the surface of such portions,  118 ,  120 ,  124  and  126 . Reactive layer  122  can be constructed from a variety of reactive matter including matter having a higher physical or chemical affinity for the contaminants relative to the material of the lens, and from matter having active sites such as enzymatic sites for cleaning and thereby facilitating removal of contaminants from the lens.  
         [0029]    Alternatively, reactive layer  122  can take the form of a separate sheet or film such as a sheet or a film of PTFE or of a solid phase having enzymatic matter bound to it such as a cellulose paper which is coated with enzymatic matter. The cellulose paper can be in sheet form which is pre-applied to the external surfaces of the interior of container body  110  or in sheet form which is supplied separately for insertion into container body  110 . It will be appreciated that such sheet form can be provided in different sizes and configurations to enable ease of use and accommodate economy concerns.  
         [0030]    For example, reactive layer sheets  122  can be sized to fit within the container body  110  and entirely coated with reactive matter to guard against misalignment of the sheets when inserted into the container body relative to the location of convex and concave portions  118 ,  120 ,  124 , and  126 . Alternatively, the sheets can be sized to fit within the container body and the coating of reactive matter can be limited to those areas of the sheet designed to align with convex and concave portions  118 ,  120 ,  124 , and  126 . Alternatively, reactive layer  122  can be a solid phase having bound reactive matter, such as an enzyme coated cellulose paper, in “button” form which is sized and dimensioned for direct placement on convex and concave portions  118 ,  120 ,  124 , and  126 .  
         [0031]    During use, the user places the contact lens to be cleaned on reactive layer of the first body section. The second body section is then folded over the first body section. As shown in FIG. 4, when the apparatus is closed the reactive surfaces of the first and second body sections are brought into contiguous engagement of the optical surfaces of a lens. The second body section and the first body section are held together the closed arrangement through a releaseable latch and when latched together the first and second body sections preferably form a fluid tight housing. For example, lower body section  114  can be formed to include a ledge  119  which engages a complimentary shaped resilient protrusion  117  formed in upper body section  112  to maintain lower body section  114  and upper body section  112  in a liquid sealed condition for containing liquid within the container. One or both of lower body section  114  and upper body section  112  can include a tab  121  to facilitate opening and closing the container. As shown in FIG. 4, when the first and second body sections are brought together there is a conforming contiguous contact between the optical surfaces of lens and the respective contacting reactive layer surfaces and there is a defined volume inside the chamber capable of holding excess ophthalmological fluid.  
         [0032]    [0032]FIG. 6 shows another embodiment of a lens treatment apparatus  140  in accordance with the present invention including a container  150  having an upper body section  152  and a lower body section  154  flexibly joined together by spine  156 . Upper body section  152  and lower body section  154  are recessed forming chambers  158 ,  160  respectively, with lower chamber  160  having a greater depth than upper chamber  158 . A sponge material  162  dimensioned to fit snugly in chambers  158  and  160  is positioned in container  150 .  
         [0033]    The sponge material  162  has an upper body portion  164  and a lower body portion  166  joined together by spine portion  168  so that upper body portion  164  and lower body portion  166  are in fluid communication through spine portion  168 .  
         [0034]    The sponge material is provided with generally convex surfaces  118  and  120  and generally concave surfaces  124  and  126  over which is a thin layer of reactive material  122 . Prior to use of the apparatus  140 , sponge material  162  is preferably moistened with an opthalmologically compatible solution. The solution can be prepackaged with the apparatus or placed in the apparatus prior to use.  
         [0035]    The apparatus is opened to receive contact lenses for cleaning. When contact lenses are inserted in the apparatus for cleaning, the apparatus is closed by the user and the accompanying compression of sponge sections  164  and  166  causes solution absorbed therein to flow around the ends of reactive layers  122  and around and under the lenses providing a fluid communication interface.  
         [0036]    Preferably lower section  160  has a recessed section to form a well or internal collection chamber  170  for the opthalmologically compatible solution to retain excess fluid and to mitigate against fluid seeping out of the apparatus. After use the apparatus is opened and the lenses are removed. When left open, fluid retained in upper sponge body portion  164  is drawn to lower sponge  166  through sponge spine portion  168  due to the difference in the relative fluid retaining capacities of upper sponge body portion  164  and lower sponge body portion  166  and gravity. In particular, because of the depth of recess forming chamber  158  relative to the depth of chamber  160 , lower portion  166  has a greater fluid retaining capacity than upper section  164  due to its greater volume.  
         [0037]    [0037]FIG. 5 shows another embodiment of a lens treatment apparatus  200  constructed in accordance with the present invention including a container  210  having an upper body section  212  and a lower body section  214  flexibly joined together by spine  216 . Upper body section  212  and lower body section  214  are recessed forming chambers  218 ,  220 , respectively. A sponge material  222  dimensioned to fit snugly in chamber  218  is positioned in container  210 . A sponge material  224  dimensioned to fit snugly in chamber  220  is positioned in container  210 . Upper sponge  222  is dimensioned to have a greater depth than the depth of upper section  218 , that is sponge  22  is oversized relative to the depth of section  218 , and sponge section  224  is dimensioned to have a depth less than that of lower section  220 , that is it is undersized relative to the depth of section  220 . Sponge  222  and  224  are dimensioned so that their respective depths are complementary so that when apparatus  200  is in a closed configuration sponge  222  and sponge  224  are in a relatively compressive configuration with respect to each other. Sponge  222  is provided with a cooperatively aligned, generally convex surface  118  and sponge section  224  is provided with generally concave surface  124  over each of which is a thin layer of reactive material  122 . Upper section  218  is provided with inwardly deformable portions  226 ,  228  and lower section  220  is preferably also provided with inwardly deformable portions  230 ,  232 .  
         [0038]    Prior to use of the apparatus  200 , sponge  222  and  224  are preferably moistened with an opthalmologically compatible solution. The solution can be prepackaged with the apparatus or placed in the apparatus prior to use. The apparatus is opened to receive contact lenses for cleaning. After the contact lenses are inserted in the apparatus for cleaning, the apparatus is closed by the user. The user then depresses inwardly deformable portions  226 ,  228 ,  230  and  232  and the depression of those sections together with the compression of sponge  222  and  224  causes solution absorbed in sponges  222  and  224  to flow around the ends of reactive layers  122  and around and under the lenses providing a fluid communication interface. Preferably inwardly deformable portions  226 ,  228 ,  230 , and  232  are generally irreversibly deformable to promote disposal of the unit after use. The differential in height between lower section  220  and lower sponge  224  forms a well or internal collection chamber  234  for the optimologically compatible solution to retain excess fluid and to mitigate against fluid seeping out of the apparatus during use or when the apparatus is opened. While apparatus  200  has been shown to include a single convex portion  118  and a single concave portion  124 , it will be appreciated by those skilled in the art that a plurality of concave and convex portions can be provided so that apparatus  200  can be used to clean more than one lens at one time.  
         [0039]    [0039]FIG. 7 shows the lower half of another embodiment of a lens treatment apparatus  250  in accordance with the present invention including a container  260  having cooperative upper body and lower body sections joined together by a hinged portion or fold line similar to the construction shown for apparatus  100  in FIG. 1. While the following discussion of FIG. 7 is directed to the configuration of the lower body section of apparatus  250 , it will be appreciated by those skilled in the art that the upper body section will be constructed in a complementary manner to cooperatively provide a working lens treatment apparatus. With specific reference to FIG. 7, apparatus  250  is seen to have a lower body section  260  having an interior portion  262 . The interior portion  262  of lower body section  260  is formed to have a concave recessed portion  264  surrounded by shoulders  266 . A relatively thin layer or film of compliant material  268 , such as a deformable metal foil is adhered to and supported by shoulders  266 . Compliant layer  268  spans recess  264 , and partially or fully covers recess  264 . A layer of reactive material  122  covers the recess covering portion of compliant layer  268 . A pocket  270 , filled with air or other highly compliant matter, is formed between compliant layer  268  and recess  264  which provides a compliant cushion for a lens placed into apparatus  260  for cleaning.  
         [0040]    [0040]FIG. 8 shows the lower half of another embodiment of a lens treatment apparatus  280  in accordance with the present invention. The embodiment shown in FIG. 8 is similar to the embodiment shown in FIG. 7. The embodiment shown in FIG. 8 differs from that shown in FIG. 7 in that the compliant layer  268  is supported above, instead of on, shoulders  266  to ensure the lens is cushioned regardless of its location on complaint layer  268 . In the embodiments illustrated in FIG. 7 and FIG. 8, pocket  270  also defines an interior volume within the chamber which can also hold an opthalmologically compatible solution to provide a moist environment for reactive layer  122  and/or lens  155 .  
         [0041]    While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader respects. In that regard, it will, of course, be appreciated that the features of the various embodiments can be interchanged and combined to form lens cleaning apparatus within the scope of the present invention. For example, the lens cleaning apparatus could be constructed with one section having a sponge member supporting the reactive layer and the other section having a different compliant material supporting its associated reactive layer, e.g. fibrous cellulose or a thin film such as a compliant metal foil. Additionally, it will be appreciated that the deformable case features illustrated and described with reference to FIG. 5 can be incorporated in other embodiments of the invention including, but not limited to, those shown in FIGS.  1 - 4  and  6  herein. Additionally, the lens cleaning apparatus of the present invention can be constructed to receive a single lens or a plurality of lenses. Accordingly, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.