Abstract:
Swimming goggles or diving masks having a polarized lens of the present invention include a sealed polarized lens unit. The sealed polarized lens unit has a seal member covering and extending beyond the peripheral edge of the laminated polarized lens to protect the polarized lens from de-lamination resulting from encroaching moisture. A non-polarized lens may be optionally affixed in the frame to provide additional protection of the polarized lens, from water impact. Swimming goggles or diving masks having polarized lenses provide a glare-eliminating feature which is particularly useful for water sports where glare significantly inhibits participant vision.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is based on and claims benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent application No. 60/298,400, filed on Jun. 18, 2001. 
     
    
     
       TECHNICAL FIELD  
         [0002]    The present invention relates to protective lenses, particularly to eyewear with polarized lens, and is more especially directed to eyewear with polarized lens for water sports, such as swimming goggles, diving masks and the like.  
         BACKGROUND OF THE INVENTION  
         [0003]    Polarization is one of the fundamental properties of light waves. Generally, in an unpolarized wave, the vibration in a plane perpendicular to the ray appears to be oriented in all directions with equal probability. In a polarized wave the displacement direction of the vibrations is completely predictable. When light is reflected from a surface, it is partially polarized. When it is reflected at a particular angle, for example 53° in the case of water, it is completely polarized. Such polarized light produces undesirable effects which are an increase in brightness and a reduction in colour saturation such that glare occurs. This makes objects viewed in the presence of glare appear to be washed-out and causes eye strain and discomfort. Tinted glasses or plastic lenses cannot solve the problem of glare. Such glare is particularly acute when reflected from water surfaces, the surface of snow, shiny vehicle hoods or roadways, and is generally polarized in a plane parallel to the reflecting surface.  
           [0004]    A major advantage of eye glasses having polarized lenses is the ability to reduce glare from light striking reflective surfaces. When such polarized glare is viewed through a polarizer, the glare is completely eliminated. Polarized sun glasses reduce glare by having a vertical transmission axis, but blocking the dominantly horizontally polarized reflected light from horizontal surfaces.  
           [0005]    It is well known to make sun glasses having polarized lenses. U.S. Pat. No. 4,838,673, issued to Richards et al. on Jun. 13, 1989, describes a sunglass lens which includes two layers of ground and polished mineral glass laminated together with a polarized film between the two glass layers to form a single lens having an inner and an outer surface. An anti-reflectent coating is attached to the inner surface of the lens and a bigradient coating is attached to the outer surface of the lens. U.S. Pat. No. 5,327,180, issued to Hester, III et al., on Jul. 5, 1994, as another example of sunglasses having polarized lenses, describes a polarized lens and a pair of glasses incorporating the lens. Similar to the lens described by Richards et al., the lens described by Hester, III et al. includes two lens elements, preferably formed of mineral glass, laminated together with a polarization film therebetween. The laminated lens is also applied with anti-reflectent coating and additionally with waterproof coatings.  
           [0006]    It is also known that a light polarizing visor can be incorporated into a glare shielding board to be pivotally secured adjacent to the rearview mirror of a vehicle, as described in U.S. Pat. No. 6,089,643, issued to Wang et al. on Jul. 18, 2000.  
           [0007]    The reduction in glare by polarized lenses can be dramatic. Nevertheless, this is not fully recognized and appreciated by many members of the public who purchase sunglasses and who often are more concerned with the tint and general reduction of light provided by sunglasses rather than selective reduction of polarized light. Moreover, the importance of wearing swimming goggles or diving masks with polarized lenses has not been fully recognized even through it is well known that the polarized lenses are particularly effective around water. Polarized glare reflected from the water surface inhibits the water sport participant who is positioned on the ground for jumping or diving, from viewing under the surface of the water. This can be dangerous to the participant.  
           [0008]    Generally, sunglasses cannot replace swimming goggles or diving masks because sunglasses cannot provide the eye protection offered by swimming goggles or diving masks, with the exception of light shielding. Polarized lenses available in the marketplace are thinner than normal lenses used for swimming goggles and diving masks, and cannot sustain water pressure and water impact forces related to water sports, especially when the wearer is jumping or diving into the water.  
           [0009]    Another problem regarding polarized lenses used for water sport eyewear is delamination caused by moisture contacting the peripheral edge of the laminated polarized lens. The laminated polarized lenses are vulnerable to moisture encroaching from the peripheral edge thereof. Hester III et al. provide additional waterproof coatings to the laminated lens of sunglasses. However, the waterproof coatings do not protect the peripheral edge of the laminated polarized lens from contacting moisture. In prior art, lenses are affixed in frames of swimming goggles or diving masks, usually in a relatively water-tight manner to prevent significant water leakage into the goggles or masks when the goggles or masks are worn on the head of a wearer and a gasket around the frame is pressed against the wearer&#39;s face. Nevertheless, this type of water-tight manner does not ensure that moisture is prevented from contacting the peripheral edge of the lens, encroaching from either side of the lens. It is common for a wearer to remove the swimming goggles or diving mask from his/her head and put same into water to wash off moisture condensation collected on the inner side of the lens. It is also noted that in prior art, lenses are received directly in frames, the sealing properties of which normally rely on the elastic deformation of the frames. As a result, the sealing properties provided by the frame around lenses are not adequate with respect to the requirement of preventing moisture from contacting the peripheral edge of the lenses, because the frame material must be rigid or semi-rigid in order to maintain its shape, which compromises its elastic properties and therefore adversely affects the sealing result.  
           [0010]    The Applicant is aware of no swimming goggles or diving masks with polarized lenses currently available in the marketplace, nor is the Applicant aware of public documentation providing technical description of swimming goggles or diving masks with polarized lenses. U.S. Pat. No. 5,191,363, issued to Smith et al. on Mar. 2, 1993, describes sports glasses with a water-tight seal and merely mentions a lens, preferably polarized. Smith et al. neither address the particular sealing requirement of the peripheral edge of the polarized lenses, nor provide technical teachings for such a seal. Therefore, there is a need for swimming goggles and diving masks with polarized lenses which overcome the above mentioned problems.  
         SUMMARY OF THE INVENTION  
         [0011]    It is one object of the present invention to provide swimming goggles or diving mask with polarized lenses.  
           [0012]    In accordance with one aspect of the present invention eyewear is provided for water sports. The eyewear comprises at least one laminated polarized lens having means surrounding and sealing a peripheral edge thereof, for preventing moisture from contacting the peripheral edge of the laminated polarized lens. The lens and means forms a sealed lens unit. A frame is provided to receive the sealed lens unit affixed therein. Retaining means are attached to the frame for holding the eyewear against the face of a wearer thereof.  
           [0013]    The eyewear used for water sports according to the present invention, in particular swimming goggles or a diving mask, preferably has the laminated polarized lens protected from water impact by a non-polarized lens.  
           [0014]    The means surrounding and sealing the peripheral edge of the laminated polarized lens preferably comprise an elastomeric and water-impermeable ring in tension, covering and extending beyond the peripheral edge thereof; or preferably comprise a water-impermeable sealing film covering and extending beyond the peripheral edge of the laminated polarized lens in a water-tight manner.  
           [0015]    In one embodiment of the present invention, the non-polarized lens is a conventional lens of swimming goggles or a diving mask. The sealed lens unit containing the laminated polarized lens with the seal ring as a single piece, for example, is glued to the inside of the swimming goggles or diving mask. Thus, the conventional lens that is positioned on the outer side of the sealed lens unit protects the polarized lens from water impact and the seal members, such as the elastomeric ring of the sealed lens unit protect the peripheral edge of the laminated polarized lens from contacting moisture even when the swimming goggles or diving mask are off the wearer&#39;s head and are immersed in water.  
           [0016]    In another embodiment of the present invention, the laminated polarized lens is laminated together with the non-polarized lens. A seal member, preferably the elastomeric ring, covers and extends beyond the peripheral edge formed by both the laminated polarized lens and the non-polarized lens in a water-tight manner, in order to prevent moisture from contacting the peripheral edge. The seal member secures the laminated polarized lens and the non-polarized lens together to form the sealed lens unit. The sealed lens unit containing the polarized lens is affixed in the frame of the swimming goggles or diving mask. The laminated polarized lens which constitutes layers of the sealed lens unit positioned in the swimming goggles or diving mask to be closest to the wearer&#39;s face while in use, is protected by the non-polarized lens which constitutes the outer lens surface when positioned in the swimming goggles or diving mask while in use. The non-polarized lens is preferably made of polycarbonate plastic.  
           [0017]    The glare eliminating feature of the swimming goggles or diving mask having polarized lenses according to the present invention is particularly useful for water sports where glare significantly inhibits participant vision. The swimming goggles or diving mask of the present invention provide the wearer with better vision through the water surface before the wearer jumps or dives into the water, to improve the safety of the water sport participant.  
           [0018]    Other advantages and features of the present invention will be better understood with reference to preferred embodiments of the present invention described hereinafter. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]    Having thus generally described the nature of the present invention, reference will now be made to the accompanying drawings, showing by way of illustration the preferred embodiments thereof, in which:  
         [0020]    [0020]FIG. 1 is a front view of swimming goggles having polarized lenses according to the present invention;  
         [0021]    [0021]FIG. 2 is a perspective view of a portion of the swimming goggles cut along line  5 - 5  of FIG. 1 and showing a lens structure thereof according to one embodiment of the present invention;  
         [0022]    [0022]FIG. 3 is a perspective view of a portion of the swimming goggles similar to that of FIG. 2, showing the lens structure according to another embodiment of the present invention;  
         [0023]    [0023]FIG. 4 is a perspective view of a portion of the swimming goggles similar to that of FIG. 2, showing the lens structure according to a further embodiment of the present invention;  
         [0024]    [0024]FIGS. 5 a - 5   b  are cross-sectional views of the swimming goggles taken along line  5 - 5  of FIG. 1, showing details of a sealed lens unit according to various embodiments of the present invention, and being used with the lens structures shown in FIGS. 2 and 4;  
         [0025]    [0025]FIGS. 5 c - 5   d  are cross-sectional views of the swimming goggles also taken along line  5 - 5  of FIG. 1, showing details of a sealed lens unit according to further embodiments of the present invention and being used with the lens structure shown in FIG. 3; and  
         [0026]    [0026]FIG. 6 is a perspective view of a diving mask having a polarized lens according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0027]    With reference to the drawings and in particular to FIG. 1, a pair of swimming goggles having polarized lenses according to the present invention, generally designated with reference numeral  10 , is shown. The pair of swimming goggles  10  comprises a frame structure  12  with two frame sections  14 ,  16  and a bridge  18  connected between an inner side of the frame sections  14 ,  16  of the frame  12 . A head strap  20  including sections  22 ,  24  is affixed to an outer side of the respective frame sections  14 ,  16  to be connected to each other by means of fasteners  26 ,  28  which are attached to the free end of the strap sections  22 ,  24 , respectively. Each of the frame sections  14 ,  16  of the frame  12  has a sealed polarized lens unit  30  affixed therein and a gasket  32  or  34  extending along the lens section of the frame  12 .  
         [0028]    Reference will now be made to FIGS. 2 and 5 a . The sealed polarized lens unit  30  includes a polarized lens  36  and a seal member  46  surrounding a peripheral edge of the polarized lens  36 . The polarized lens  36  must be a laminated multi-layer lens because the polarized lens  36  generally includes a polarized filter film  36   a  sandwiched between two layers  36   b  and  36   c  of glass or any transparent plastic such as polycarbonate or acetate.  
         [0029]    Laminated polarized lenses and a method of making same are well known in the industry, examples of which are described in U.S. Pat. Nos. 4,838,673 and 5,327,180, the specifications of which are incorporated herein by reference. There now exist in the market place, laminated polarized lenses  36  having the polarization filter film  36   a  laminated between layers  36   b  and  36   c  of acetate plastic, polycarbonate plastic or glass, or a combination of those materials. Generally, any kind of laminated polarized lenses  36  can be used in the sealed polarized lens unit  30 , for the swimming goggles  10  when the laminated polarized lenses  36  are adapted to resist water impact related to water sports.  
         [0030]    However, delamination may occur, beginning at the peripheral edge of the laminated polarized lens  36  when moisture contacts the peripheral edge thereof and encroaches therefrom. Therefore, the seal member  46  is provided to seal the peripheral edge of the laminated polarized lens  36 , thereby preventing moisture from contacting the peripheral edge thereof.  
         [0031]    In accordance with one embodiment of the present invention, the seal member  46  is an elastomeric and water-impermeable ring  46   a , as more clearly shown in FIG. 5 a . The ring  46   a  includes an annular groove  43  on an inner periphery, for receiving the peripheral edge of the laminated polarized lens  36  therein. The elastomeric ring  46   a  is mounted in tension around the laminated polarized lens  36 , thereby covering and extending beyond the peripheral edge thereof, in order to achieve a water-tight sealing of the edge. The combination of the laminated polarized lens  36  and the elastomeric and water-impermeable ring  46   a  forms the sealed polarized lens unit  30 .  
         [0032]    It is optional to apply a liquid or semi-liquid adhesive between the peripheral edge of the laminated polarized lens  36  and the ring  46   a  to further assure the sealing result.  
         [0033]    The sealed polarized lens unit  30 , as an integral single piece, is affixed in the frame section  14  or  16  (only frame section  16  is shown) in a manner well known in the industry. For example, the ring  46   a  that surrounds the periphery of the laminated polarized lens  36  is snugly received within a continuous groove  40  in each frame section  14  or  16 .  
         [0034]    Referring to FIGS. 2 and 5 b , the seal member  46  according to another embodiment, is a water-impermeable sealing film  46   b  which is exaggerated in FIG. 5 b  for better illustration. The sealing film  46   b  covers and extends beyond the peripheral edge of the laminated polarized lens  36  in a water-tight manner. For example, liquid or semi-liquid masses are coated on and over the peripheral edge of the laminated polarized lens  36  and are allowed to harden to form the sealing film  46   b  before the laminated polarized lens  36  is affixed in the frame section  14  or  16 . Then, the sealed lens unit  30  is affixed in each frame section  14  or  16  in a conventional manner.  
         [0035]    It is noted that acetate polarized lenses are most cost effective and therefore widely used, in contrast to other plastic or glass polarized lenses which are more difficult to manufacture. The higher melting point of polycarbonate, for example, causes the polarization filter film to melt, resulting in a high rejection rate and requiring costly specialized equipment. Therefore, acetate polarized lenses are an economic choice and will be popularly used for eyewear until the manufacturing costs of the polycarbonate polarized lenses decreases and the use of polycarbonate polarized lenses becomes more popular, which will result from the improvement of manufacturing techniques.  
         [0036]    However, acetate polarized lenses are very thin and are not adapted to resist water impact related to water sports when the wearer&#39;s safety is concerned. In such cases an additional lens should be included in the sealed polarized lens unit  30  to protect the thin polarized lens from breaking under water impact. Examples are described below, showing the various structures of the swimming goggles  10  having the thin laminated polarized lens  36  protected by an additional non-polarized lens.  
         [0037]    In FIGS. 3 and 5 c , the sealed polarized lens unit  30 ′, according to a further embodiment includes a thin laminated polarized lens  36 , for example, made of acetate plastic lenses  36   b  and  36   c  which sandwich the polarized filter film  36   a , and a non-polarized lens  38  for example, made of polycarbonate plastic. The thin laminated polarized lens  36  is laminated to the non-polarized lens  38  to form a sole lens. The peripheral edge formed by both the laminated polarized lens  36  and the non-polarized lens  38  is received in the annular groove  43  of the elastomeric and water-impermeable ring  46   c  which forms the seal member  46  and in tension covers and extends beyond the peripheral edge thereof. Therefore, the peripheral edge formed by both the laminated polarized lens  36  and the non-polarized lens  38 , is protected from contacting moisture. It is optional to apply liquid or semi-liquid adhesive between the ring  46   c  and the edge formed by both the laminated polarized lens  36  and the non-polarized lens  38  in order to assure the sealing result.  
         [0038]    The non-polarized lens  38  constitutes an outer lens surface of the swimming goggles  10  when the sealed polarized lens unit  30 ′ is affixed in each frame section  14  or  16  (only frame section  16  is shown). The mounting is similar to that of the sealed polarized unit  30  illustrated in FIG. 2 and will not therefore be redundantly described. Thus, the thin polarized lens  36  is protected by the relatively thicker and stronger non-polarized lens  38 , from water impact.  
         [0039]    Similar to the sealing film  46   b  of the embodiment described with reference to FIGS. 2 and 5 b , the seal member  46  of the sealed polarized lens unit  30 ′ can also be formed by a sealing film  46   d , as illustrated in FIG. 5 d . The sealing film  46   d  covers and extends beyond the peripheral edge of the sole lens formed by both the laminated polarized lens  36  and the non-polarized lens  38 . The sealing film  46   d  in this embodiment must have sufficient strength to secure the laminated polarized lens  36  and the non polarized lens  38  together to form the sealed polarized lens unit  30 ′.  
         [0040]    In a still further embodiment of the present invention as shown in FIG. 4, the sealed polarized lens unit  30  which includes the polarized lens  36  and the seal member  46 , is protected by a separate non-polarized lens  38 . The non-polarized lens  38  is accommodated at its periphery within the continuous groove  40  of the frame section  14  or  16  of the frame  12  (only frame section  16  is shown), as seen in a conventional swimming goggle structure. The sealed polarized lens unit  30  is fitted within the frame section  16  and is affixed by means of glue for example, to a continuous inner shoulder  48  of the frame section  16 . The space between the sealed polarized lens unit  30  and the non-polarized lens  38  may not be necessary, provided that the sealed polarized lens unit  30  can be securely attached within the frame section  16  of the frame  12 . The laminated polarized lens  36  is protected by the separate non-polarized lens  38  from water impact, and protected by the seal member  46  from de-lamination resulting from encroaching moisture. This embodiment provides a simple method to convert an existing pair of swimming goggles with non-polarized lens into a pair of swimming goggles with polarized lenses.  
         [0041]    [0041]FIG. 6 illustrates a diving mask, as still further example of the present invention. The diving mask  50  includes a frame  52 , a window containing a sealed polarized lens unit  54  and a soft skirt  56 . The frame  52  provides a pair of strap receptacles  58  for receiving a strap (not shown) for securing the mask  50  to the face of a wearer.  
         [0042]    The skirt  56  is made of flexible, soft, water-tight, rubber-like material, and is preferably transparent. The diving mask  50  may include further features which a conventional diving mask may have, such as side window lenses  60 , a nose enclosure  62  and nose compression recess  64  on one side of the nose enclosure  62 . Those features are well known and are described, as an example, in U.S. Pat. No. 5,860,168, issued to Winfordner et al. on Jan. 19, 1999, the specification of which is incorporated herein by reference.  
         [0043]    The sealed polarized lens unit  54  is similar to the polarized lens units  30  and  30 ′ shown in FIGS. 5 a - 5   d . The various embodiments of the sealed polarized lens units  30  and  30 ′ illustrated in FIGS. 5 a - 5   d  and various polarized lens structures used in the swimming goggles illustrated in FIGS.  1 - 4  are all applicable to the diving mask  50  and will not therefore be redundantly described. The non-polarized lens  38  in FIGS. 3 and 4, when used in the diving mask  50 , whether integrated with or separate from the sealed polarized lens unit  54 , will provide protection of the polarized lens unit  54 , not only from water impact but also from water pressure.  
         [0044]    Modifications and improvements to the above-described invention may become apparent to those skilled in the art. For example, the sealed polarized lens unit may be counter-sunk into the plastic swimming goggle frame or sonic weld can be used to secure the sealed polarized lens unit to the plastic swimming goggle frame. The forgoing description is intended to be exemplary rather than limiting. The scope of the invention is therefore, intended to be limited solely by the scope of the appended claims.