BACKGROUND OF THE INVENTION

[0001] This invention relates to an apparatus for cleansing and disinfecting optical contact lenses. [0002] Contact lenses are widely used as an effective alternative to spectacles. During a period in which a contact lens is worn on an eye, films comprising proteins, lipids and mucous build up on the lens' surface. Over time, these films sequester micro-organisms such as bacteria, fungi and viruses and chemotactically attract inflammatory molecules. The presence of these micro-organisms and molecules causes inflammatory reactions on the corneal surface which lead to discomfort, red eyes and contact lens intolerance. In order to avoid these effects, it is crucial that proper daily hygiene procedures are followed to remove these films in order to minimize eye irritation and infections.

[0003] Typically, contact lenses are treated using a multipurpose contact lens cleaning solution to clean and sterilize the lenses after daily use. The lenses are submerged and left overnight in a container containing the solution. The solution then works to clean and sterilize the contact lenses while also rinsing, lubricating and removing any protein buildup.

[0004] However, use of the solution alone is not effective in totally removing the films formed on the lenses. For more thorough removal, wearers are advised to rub the contact lenses with their fingertips in order to ensure that the films are completely removed . This process is effective, but many wearers find the manual rubbing process to be time- consuming and a hassle factor and, therefore, do not perform this step on a daily basis Over time this can result in a reduced clarity and the possibility of contact lens discomfort and eye infection. Furthermore, rubbing that is too vigorous may damage the contact lens surface, a consequence which inhibits the effectiveness of the lens.

[0005] Various mechanisms that provide an alternative to rubbing do exist in the art. One such mechanism uses a geared system to agitate a liquid surrounding contact lenses, thereby cleaning them. Another mechanism uses an electrical power source to generate an acoustic resonant signal at a frequency which disrupts the films on the contact lenses. While these methods can be effective, they are complex and expensive to implement. Furthermore, the geared mechanism is prone to breakage and frequent replacement may be required. [0006] An object of the present invention is to address, at least to some extent, the aforementioned drawbacks.

SUMMARY OF INVENTION

[0007] The invention provides an apparatus for cleansing contact lenses, the apparatus including a container which defines an internal volume for receiving a cavitation-supporting liquid , an opening to the volume, a closure engageable with the opening to seal the l iq u id within the volume, a lens holder within the volume for releasably holding at least one contact lens such that the lens is suspended within the liquid in the volume, and at least one cavitation-enhancing formation, and wherein , upon agitation of the liquid , the cavitation-supporting liquid is aerated at least by the cavitation-enhancing formation . causing the formation of bubbles which clean the lens by means of cavitation action

[0008] The at least one cavitation-enhancing formation may be provided in any suitable way. The formation may be in the form of a grid or mesh which bounds at least a part of the volume. The grid or mesh may be held captive within the volume with a friction fit or may be integral with the container.

[0009] In an alternative embodiment, the cavitation-enhancing formation is one of a plurality of projections e.g. inwardly projecting formations on an inner wall of the container

[0010] The cavitation-enhancing formation may be such that, upon agitation of the container, the cavitation-supporting liquid is repeatedly brought into contact with, or agitated against, the cavitation-enhancing formation thereby causing bubbles to be formed in the liquid. In turn, a plurality of bubbles create what may be considered to be a foam.

[0011] The lens holder may be of any suitable kind to support the lenses within the cavitation-supporting liquid. The lens holder may include at least one aperture, through which liquid flows. Preferably a plurality of apertures are provided.

[0012] The lens holder may include two compartments which respectively receive a right- side contact lens, and a left-side contact lens. Each compartment may be of a complementary shape to a corresponding contact lens such that each contact lens is nested within, or closely received by, the respective compartment.

[0013] At least a part of each compartment may be movable, relative to the lens holder to allow a user to gain access to the compartment. A part of each compartment may be movable with a hinge action, between a first position, at which the compartment is closed, and a second position at which the compartment is open.

[0014] The lens holder may include at least one cavitation-enhancing formation. In one form of the invention, the lens holder is formed from a member, or a material, having cavitation-enhancing properties e.g. a mesh or grid material with apertures of a suitable size. In use the cavitation-supporting liquid is caused to pass through the apertures and the liquid is thereby caused to foam or bubble.

[0015] Additionally or alternatively, the lens holder includes a plurality of protuberances on a surface or surfaces thereof. Preferably these cavitation-enhancing formations are formed on at least one of an inner surface of the lens holder and an outer surface thereof.

[0016] The lens holder may be engageable with, or may be integral with, the closure such that the lens holder is suspended within the liquid e.g. by means of a rod. The rod may be movable, relative to the container, to position the lens holder in the bubbles.

[0017] Structure may be provided on the container or the closure or both, in order to move the closure, or the lens holder, relative to the container so that the lens holder is suspended within the bubbles formed as a result of the agitation and to retain the lens holder in position in the bubbles.

[0018] In one form of the invention the structure includes complementary threaded formations on an outer surface of the container and on an inner surface of the closure. [0019] Upon agitation of the liquid e.g. by shaking the container or by moving the grid or the lens holder through the liquid , bubbles are formed in the cavitation-supporting liquid . The lens holder may then be movable so that the lens holder is suspended within the bubbles. This allows the lenses to be cleaned by way of a cavitation action i.e. as the bubbles burst. [0020] The container and the lens holder may be formed from any suitable plastics material. Preferably a Bisphenol A - free plastics material is used.

[0021] The cavitation-supporting liquid may be of any suitable kind to cleanse and sterilise the contact lenses. [0022] The invention also provides a method of cleaning a contact lens which includes the steps of forming bubbles in a lens-cleaning liquid, immersing the lens in the bubbles and exposing the lens to cavitation action caused by the bubbles collapsing, thereby to remove unwanted protein, lipid and mucous build-up on a surface of the lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The invention is further described by way of examples with reference to the accompanying drawings in which:

Figure 1 illustrates from one side an apparatus according to the invention ,

Figure 2 is a side view of a lens holder of the apparatus in Figure 1 ;

Figure 3 is a side view of a modified lens holder;

Figure 4 shows the apparatus of Figure 1 wherein a lens holder has been moved so that it is in contact with bubbles; and

Figure 5 illustrates, from one side, a modified apparatus according to the invention. DESCRIPTION OF PREFERRED EMBODIMENTS

[0024] Figure 1 of the accompanying drawings shows, from one side, an apparatus 1 0 according to the invention. The apparatus 10 includes a container 12. having an internal volume 14, an opening 16 to the volume and a closure 18 removeably engageable with the container 12 such that it bounds the opening 16. The closure may be in the form of a cap which is threadedly engaged with the container.

[0025] A lens holder 20 is supported inside the volume 14 by means of a rod 20A which is integral with, or which is secured to an inner surface of, the closure 1 8 by any suitable means. The lens holder is configured to hold lenses which are to be cleaned . The lens holder 20, also shown in Figure 2, is in the form of an apertured cage 21 which defines two chambers 22 and 24 for receiving a left and a right contact lens respectively. Surfaces of the chambers 22 and 24 are respectively of complementary shape to these lenses to ensure that each lens is held securely in place. Respective portions 22A and 24A of the cage, which form closures for the chambers, are pivotally movable about respective hinges 22B and 24B to allow a user to access interiors of the chambers.

[0026] The container 12 includes a cavitation-enhancing member 25 which is in the form of a mesh or grid 26, having a plurality of apertures through which a liquid passes when the container is agitated. The mesh or grid 26 is positioned within the container and for example is attached to the rod 20A to ensure that a maximum volume of liquid can flow through the apertures.

[0027] For improved cavitation action, in a variation of the invention (refer to Figure 3), the lens holder 20 is formed from a mesh or grid material 26A which replaces the cage 21 of Figure 2, and which defines a plurality of apertures 27 of suitable size through which , upon agitation of the container 12, a cavitation-supporting liquid 28 (see Figure 1 ) passes. The grid material 26A increases the quantity of foam or bubbles which are produced and this leads to an enhanced cavitation action.

[0028] In another modification the lens holder 20 includes a number of protuberances 26B on a surface thereof, as is shown in Figure 3.

[0029] Another way of producing bubbles is to provide a number of inwardly extending projections 29 on an inner surface of the container 12 that upon agitation of the container the liquid is forced past and through the projections.

[0030] In use, a user places a left contact lens 30 (to be cleaned) into the chamber 22 and a right contact lens 32 (to be cleaned) into the chamber 24 of the lens holder 20 - see Figures 2 and 3. The cavitation-supporting liquid 28 partly fills the volume 14 to a desired level 36, e.g. half way so that the lens holder 20 is immersed in the liquid 28 as is shown in Figure 1 . The cavitation-enhancing liquid is preferably a multipurpose contact lens solution , which has cavitation-supporting capabilities. [0031] The opening 16 to the container 12 is sealed using the closure 1 8 (Figure 1 ). A user then vigorously shakes the container thereby repeatedly bringing the cavitation- supporting liquid 28 into contact with the mesh or grid 26 and with the formations etc. in the lens holder. This action forms bubbles which make up a foam 40. A similar process occurs as the liquid 28 passes through the apertures 27 in the lens holder 20 and additional bubbles are thus formed. The bubbles do not endure indefinitely but collapse fairly quickly due to the nature of the liquid 28. As each bubble bursts (cavitates) a force is created which helps to cause a breakdown of a lipid, protein and mucous film on the lenses, thereby cleaning the lenses.

[0032] Only a portion of the liquid 28 is converted into the foam 40. The foam 40, being less dense than the liquid 28, is on top of an upper liquid surface 42 - see Figure 4 The lens holder 20 should be kept within the foam 40 so that the lenses are exposed to the cavitation effects for an extended period. This can be done in different ways. Firstly the quantity of liquid which is used should be minimal so that once the foam is formed the lens holder, which is suspended from the closure, is automatically inside the foam [0033] In a second approach the closure 18 has a skirt 46 of an extended length d in an axial direction. An inner surface of the skirt is threaded (47) and is engageable with a complementary thread 48 on an outer surface of the container 12 adjacent the opening 16 Once the liquid 28 has been agitated the closure 1 8 can be moved in an axial direction by rotating the closure 18 relative to the container 12 and , in this way, the lens holder 20 can be axially moved within the container to ensure that the lens holder 20 is positioned inside the foam 40.

[0034] The lens holder 20 is supported inside the volume 14 by means of the rod 20A Instead of securing the rod to an inner surface of the closure 1 8 the rod 20A can extend through a lid 50 of the closure - see Figure 5. A suitable seal 52 is provided between opposing surfaces of the lid and the rod. The position of the lens holder inside the container can then be slidably adjusted by moving the rod 20A up or down relative to the container, as required, to ensure that the lens holder 20 is kept inside the bubbles 40 In a variation of this idea (not shown) the rod 20A is engaged with a screw action with a complementary thread formed in an aperture through the lid 50 and , by rotating the rod in one direction or the other, the position of the lens holder 20 is axially varied to bring the lenses into a position at which they are immersed in the foam 40.

[0035] The container is of a simple construction and the need for manual rubbing by a user is not required to cleanse the lenses. Furthermore, expensive geared mechanisms and electrical parts are not required, providing a relatively inexpensive, fuss-free and time saving device to clean contact lenses more thoroughly.

[0036] Bubbles may be induced into the liquid in any suitable way e.g . by shaking the container, or by moving the lens holder or the grid through the liquid , or by using a separate stirrer provided for this purpose. [0037] In Figures 4 and 5 the grid 26, although not illustrated , is in fact present. The grid may for example be attached to, and be movable together with, the rod 20A (in Figure 5) .