Abstract:
An eyewear system including eyeglasses having first and second lenses; first and second nose pads; and a bridge operably connecting the first and second lenses, the bridge being bendable from a bridge rest position to permit relative movement between the first and second nose pads and providing a bridge pinch force of 50 g or less between the nose pads when the nose pads are moved 7 mm or less from the bridge rest position.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of pending U.S. application Ser. No. 14/284,879, filed May 22, 2014; which is a continuation-in-part of pending U.S. application Ser. No. 13/899,606, filed May 22, 2013, which is a continuation of PCT/IB2011/055208, filed Nov. 21, 2011, which international application claimed priority to U.S. Provisional Application No. 61/344,930, filed Nov. 22, 2010. 
         [0002]    Application Ser. No. 14/284,879, filed May 22, 2014, also claims the benefit under 35 U.S.C. §119 of U.S. Provisional Application No. 61/826,127, filed May 22, 2013. The disclosures of all of these prior applications are incorporated herein by reference in their entirety. 
     
    
     INCORPORATION BY REFERENCE 
       [0003]    All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. 
       BACKGROUND 
       [0004]    The present invention relates to eyewear and in particular to Pince-Nez eyeglasses (i.e., two lens eyewear lacking temple pieces) that are comfortable, stable and have universal fit while still having full sized optics. The eyeglasses of this invention are also thin, light and easily stored. 
         [0005]    There are over 40 million people in the US that use reading glasses known as readers. Current readers typically purchased in a drug store or other mass merchandisers are designed to fit most people by using the nose as a resting place. Since nose width, angle and shape vary considerably among users, standard readers achieve their stability via the temple pieces placed above and behind the user&#39;s ears. 
         [0006]    Users wear readers at a different place down their nose in order to allow them to look over the lenses of the readers and to change the distance from the lens to the eye to adjust their effective power. The temple pieces of standard readers are usually long enough to accommodate these different positions without loss of stability of the eyeglasses on the user&#39;s face. 
         [0007]    Most Pince-Nez eyeglasses apply a significant clamping force on the nose in order to stabilize the lenses on the wearer&#39;s face. To provide a universal fit, Pince-Nez eyeglasses should accommodate noses of varying sizes and shapes at varying wearing locations while maintaining stability without user discomfort. Many Pince-Nez eyeglass designs fail to meet this standard, however. For example, while attaching Pince-Nez eyeglasses on the pliable tissues over the nostrils might help attach the eyeglasses to any size nose, most users would find this attachment location to be uncomfortable because it restricts breathing, and the glasses would be too far away from the eyes. 
         [0008]    Another common problem with readers is their availability when needed. While the temple pieces of standard readers can be folded toward the lenses to reduce the storage size of the eyeglasses, the temple pieces take up storage space, and the overall volume of the storage configuration of the readers may limit their accessibility. Because Pince-Nez eyeglasses do not have temple pieces, they present new opportunities for storage and accessibility. 
       SUMMARY OF THE DISCLOSURE 
       [0009]    The present invention relates to universal Pince-Nez eyeglasses for use as readers and/or as sunglasses. The invention also relates to eyeglasses systems including eyeglasses and storage cases for the eyeglasses. 
         [0010]    One aspect of the invention provides an eyewear system including eyeglasses having first and second lenses; first and second nose pads; and a bridge operably connecting the first and second lenses, the bridge being bendable from a bridge rest position to permit relative movement between the first and second nose pads and providing a bridge pinch force of 50 g or less between the nose pads when the nose pads are moved 7 mm or less from the bridge rest position. In some embodiments, the first and second nose pads are operably connected to the first and second lenses, respectively, via connectors adapted to permit relative movement between the first and second nose pads and the first and second lenses, respectively, and providing first and second pad forces resisting relative movement between the first and second nose pads and the first and second lenses from rest positions, the first and second pad forces being less than the bridge pinch force. The first and second nose pads may each have a cantilever extending from its respective connector. In some embodiments, the bridge force is a spring force having a spring constant greater than a spring constant of the cantilever of the first nose pad and the second nose pad. 
         [0011]    In some embodiments, the nose pads are adapted to exert less than 150 g/cm 2  of pressure on a nose of a user when the eyeglasses are mounted on the nose. The nose pads may each include friction material, such as material having a friction coefficient less than 3.5. 
         [0012]    Some embodiments of the eyewear system also include a case adapted to receive the eyeglasses, the case and eyeglasses being sized so that the bridge bends from its rest position when the eyeglasses are within the case. The bridge may be adapted to provide a retention force between the eyeglasses and the case when the eyeglasses are disposed within the case. In some embodiments, the case may also have offset frame guides sized and configured with respect to the eyeglasses to engage and fold the eyeglasses as the eyeglasses are inserted into the case. 
         [0013]    In some embodiments, the case may also have a locking element adapted to hold the eyeglasses within the case. The case may also have an opening adapted to receive the eyeglasses, the locking element being disposed to block the opening in a first position and to permit access to the opening in a second position. The case may also have a rotatable connection adapted to permit the locking element to rotate between the first position and the second position. 
         [0014]    In some embodiments, the case also has a keychain connector. The keychain connector may be disposed on the locking element. 
         [0015]    In some embodiments, the bridge of the eyeglasses has an adjustable at-rest length. In some embodiments the bridge may be connected to the first and second lenses. The bridge may also include first and second adjustable connectors adapted to move with respect to the first and second lenses, respectively, to change an effective length of the bridge. 
         [0016]    In some embodiments, the first and second nose pad connectors are connected to the first and second optical lenses, respectively. In some embodiments, the first and second nose pad connectors are adjustable to change a width between the first and second nose pads. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which: 
           [0018]      FIG. 1A  is a perspective view of Pince-Nez eyeglasses according to one embodiment of the invention. 
           [0019]      FIG. 1B  is a cross-sectional view taken along the line B-B shown in  FIG. 1A . 
           [0020]      FIG. 2  plots the distance between the tops of the nose pads versus the distance between the bottoms of the nose pads for a variety of users wearing the eyeglasses of  FIGS. 1A and 1B . 
           [0021]      FIG. 3  compares the nose pinch force provided by a variety of Pince-Nez eyeglasses. 
           [0022]      FIG. 4  is a perspective view of an embodiment of eyeglasses and case according to another embodiment of the invention in which the eyeglasses are stored flat. 
           [0023]      FIG. 5  is an elevational view of an embodiment of eyeglasses and case according to another embodiment of the invention in which the eyeglasses are stored in a folded configuration. 
           [0024]      FIG. 6  is a perspective view of an embodiment of eyeglasses and case according to yet another embodiment of the invention in which the eyeglasses are stored in a folded configuration. 
           [0025]      FIG. 7  is a perspective view of the embodiment of  FIG. 6  with the locking band in a locked position. 
           [0026]      FIG. 8  is sectional view of the case of  FIG. 4  without the eyeglasses. 
           [0027]      FIG. 9  is a partial perspective view of yet another embodiment of the eyeglasses of this invention. 
           [0028]      FIG. 10  is a perspective view of another embodiment of the eyeglasses of this invention. 
           [0029]      FIG. 11  is a perspective view of yet another case for use with eyeglasses according to this invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    Prior art Pince-Nez eyewear (see wwwdotendotwikipediadotorg/wiki/Pince-nez) typically utilize nose pads that are directly or indirectly attached to the lenses or lens frame. As a result, any changes to the distance between nose pads affect the distance between the lenses and their angular orientation and position with respect to the eyes, which can induce optical prism, introduce error in the optical cylinder axis or affect the lens aesthetics. The varying distance between the nose pads of prior art Pince-Nez eyewear further changes the nose clamp spring force, resulting in an inconsistent pinch force for different users, an unstable fit for some and discomfort for others. The large pinch force can also lead to tissue ischemia, adding to user discomfort. 
         [0031]    The present invention provides eyeglasses that are comfortable and stable on noses of nearly all sizes and shapes. Typical reading glasses weigh over 20 g, even foldable compact versions (e.g., MicroVision) with smaller lenses weigh over 14 g. It will be appreciated that in a Pince-Nez design, the weight of the eyewear is important for both stability on the nose and comfort. Heavier eyewear without ear pieces requires more clamping force to maintain stability on the nose because of the increased weight and the increased mechanical moment which causes instability when the user moves their head up and down or from side to side. Since the clamping force translates to pressure exerted by the nose pads on the tissue, a larger clamping force can lead to user discomfort, pain and in extreme cases, tissue ischemia. Thus, in some embodiments, the eyeglasses reduce the pinching pressure required to maintain a stable position by reducing the mass of the full size optics and hence reducing inertia caused by head movement and gravitational pull and increase the area of the thin nose pads to distribute the force and hence reduce the pressure further. 
         [0032]    In addition, some embodiments of the eyewear of this invention optionally increase the friction between the eyewear and the nose skin by utilizing novel nose pad materials. Such eyewear further reduces the clamping force required for stability while reducing the force causing slippage off the nose. 
         [0033]    Some embodiments of the Pince-Nez eyewear of this invention provide the nose pinch force with a super elastic bridge spring whose force does not change significantly as a function of nose width. For example, the eyewear may employ thin super elastic alloy wire made from Nitinol to interconnect the lenses (referred to herein as a lens bridge). A superelastic bridge allows repeated transformation from a worn position to a folded position for storage while exerting repeatable, controlled and nearly constant low pinch force for varying bridge deformation cause by varying width noses during wear. This feature combined with use of thin molded polycarbonate lenses results in Pince-Nez reading eyewear a large viewing zone for reading comfortably without lens distortion and without the usability compromises often inflicted by compact reading glasses. 
         [0034]    Some embodiments of the Pince-Nez eyewear of this invention provide elongated thin nose pads or folding nose pads whose specific separation distance allows the top of the pad to engage the nose via the force created by bridge spring while the bottom of the nose pad can flex or pivot to accommodate different nose angles and thus prevent the glasses from tipping forward. 
         [0035]    One embodiment of the eyeglasses of this invention is shown in  FIG. 1 . The eyeglasses  100  include full sized lenses  101  over molded on a nitinol wire bridge  102  (NDC, Fremont Calif.) with diameter of 0.010″ to 0.030″ (e.g., 0.020″) covered with an elastomer  111 . The lenses may be clear optical lenses for reading glasses or tinted sunglass lenses. 
         [0036]    In the embodiment shown in  FIGS. 1A and 1B , the lenses  101  are molded polycarbonate optical lenses less than 3 mm thick weighing less than 5 grams for 2.5 diopter full sized reading glasses with lens optical area of over 9 cm 2 . For lower optical powers or smaller optical area, the lens thickness and reader&#39;s weight can be reduced even further. For sunglasses or 3D glasses with no optical power the lenses can be less than 2 mm thick for any optical zone. 
         [0037]    The lenses  101  are attached to the super elastic bridge  102 , as shown. In alternative embodiments, the lenses can be attached to a frame, with the bridge forming part of the frame or extending between two frame sections. 
         [0038]    In the illustrated embodiment, the eyeglasses have nose pads  103  that are no wider than the lens thickness. In this embodiment, the nose pads  103  are 13 mm long (+/−4 mm). Nose pads  103  are attached to the lenses  101  (or, if there is an optional frame, to the frame) at their upper ends  104  and are free at their lower ends  105  to form cantilevers extending downward. In one embodiment, there is a 12 mm (+/−3 mm) separation between the tops  104  of the nose pads  103 , and the nose pads  103  extend downward at an angle  107  of 18°+/−4° from the vertical in their rest positions. 
         [0039]    In some embodiments, the nose pads are formed from a flexible material, such as 0.005-0.020″ (e.g., 0.010″) inch thick polycarbonate. In such embodiments, the nose pad material, shape and cantilever connection permit the nose pads  103  to bend with a spring constant that is less than the spring constant of the bridge  102 . The nose pads  103  can therefore flex to accommodate the nose geometry while permitting the entire nose pad to maintain contact with the nose. 
         [0040]    In some embodiments, a 10 mm long super elastic bridge  102  exerts a pinch force measured at the tops  104  of the nose pads  103  of less than 10 g on a narrow nose width of 12 mm, and less than 50 g (0.05 N) on a large nose width of 19 mm (all measurements+/−20%), as it flexes through angle  108  to accommodate various width noses. The 13.5 mm long nose pads  103  are 2 mm wide providing a total area of 0.24 cm 2  and thus average pressure well less than 150 g/cm 2 . 
         [0041]    The nose pads  103  may have an optional friction material (e.g., laminated onto an elastic member, such as the polycarbonate described above) to further increase the stability of the eyeglasses on the nose by minimizing slippage force due to the component of the pinch force along the surface of the skin and rotation moment due to the eyeglasses&#39; center of mass. The friction can be created by low durometer elastomers such as 3M grip tape (GM613, 3M MN, ASTM 1894 coefficient of friction measured against the same material of less than 3.5), silicone, open cell polyurethane, or micro texture sufficient to grip the skin but not to cause discomfort such as textured polymer (polycarbonate embossed with micro machined or micro molded texture) or micro grit impregnated surface (60-400 grit). 
         [0042]    Test data comparing various Pince-Nez eyeglass designs are shown in  FIGS. 2 and 3 .  FIG. 2  plots the distance (as determined by optical measurements) between the tops  104  of the nose pad  103  versus the distance between the bottoms  105  of the nose pads  103  for a variety of users (having a variety of nose sizes and shapes) each wearing the eyeglasses embodiment shown in  FIGS. 1A and 1B . The average top distance was 16.1 mm (STD 2.4 mm) with a range of 10.6-19.8 mm and a bottom distance of 23.9 mm (STD 3.1) with a range of 15.4-27.9 mm. As can be appreciated from the linear regression line  401 , no one line can be drawn so that all the users would experience proper fit. These measurements were made with the test frame positioned on the appropriate location on the nose bridge; in practice, users vary the location of the eyeglasses on their nose based on the task which adds further variability to the data. As observed in many fit studies, if the bottoms of the nose pads contact the nose while the top pads do not due to the angle and separation, the bottom contact point becomes a pivot point and the glasses easily tip over and fall off the face when the user tilts their head downward to read a tablet or menu. If the top of the nose pads contacts the nose, it becomes the pivot point and the glasses tip over making them no longer perpendicular to the visual axis compromising their usefulness. 
         [0043]      FIG. 3  compares the nose pinch force (measured at the top of the nosepads) provided by a variety of Pince-Nez eyeglasses. The embodiment shown by  FIGS. 1A and 1B  is represented by line  402 . As can be seen, the eyeglasses of this invention provide lower pinch forces than the other eyeglasses tested across a range of nose sizes. 
         [0044]    In some embodiments, the eyeglasses are designed to fit in compact storage cases, as discussed in more detail below. For example, the embodiment shown in  FIGS. 1A and 1B  may be stored flat in a case  202  extending from a housing  206  designed to be attached to the back of a cell phone  201 , as shown in  FIG. 4 . Case  202  has an opening  204  at its top into which the eyeglasses  100  may be inserted. In some embodiments, the eyeglasses  100  are slightly longer than the case  202 , and the eyeglasses are therefore bent at the bridge  102  during insertion. In such embodiments, the spring action of the bridge  102  may help retain the eyeglasses in the case. Optional retention features, such as surfaces  501  and  502 , may be provided inside the case to hold the eyeglasses within the case, as shown in the cut-away view of  FIG. 8 . In this optional embodiment, the eyeglasses bend at bridge  102  as they are inserted through opening  204  into case  202 , then unbend slightly as the lenses pass surfaces  501  and  502 . Likewise, to remove the eyeglasses from case  202 , the eyeglasses bend at bridge  102  when the lenses move toward each other as the eyeglasses are pulled through opening  204 . 
         [0045]    An optional cut-away portion  203  may leave the bridge  102  exposed after insertion so that the eyeglasses may be easily extracted from the case. In some embodiments, protruding portions of the eyeglasses (such as, e.g., features  109  and  110  shown in  FIGS. 1A and 1B ) may provide a friction fit between the eyeglasses  100  and the inside of case  202 . In some embodiments an internal storage volume of the case  202  is less than 14 cm 3  for a full 40 mm wide optical zone 2.5 diopter readers stored flat as shown in  FIG. 4 , and the case  202  is less than 4 mm thick. 
         [0046]      FIGS. 5-7  show embodiments of Pince-Nez eyeglass cases in which the eyeglasses are folded for storage. In  FIG. 5 , the eyeglasses  100  are bent at the bridge  102  to place one lens  101  over the other lens  101 . Eyeglasses  100  may be inserted through an opening  302  on one end of the case  301 . The spring force of the superelastic bridge  102  and the friction fit between the eyeglasses and the interior of the case  301  maintain the position of eyeglasses  100  within case  301 . Bridge  102  extends through opening  302  as shown to provide structure to grab for removal of eyeglasses  100  from case  301 . In this embodiment, the case  301  may be only 9 mm thick or less. 
         [0047]    In the embodiments of  FIGS. 6 and 7 , eyeglasses  100  may be inserted through an opening  804  for storage within an eyeglass case  801 . A locking band  802  rotates around pivot  803  to open the case  801  (as shown in  FIG. 6 ) or close it (as shown in  FIG. 7 ). Bridge  102  may be inserted first, as shown, and a pair of optional offset guides  803  and  804  help move the one lens  101  over the other lens  101  as the eyeglasses are advanced into case  801 . An optional keychain hook  806  may be provided for attachment of the case to a keychain or other holder. The expanding force of superelastic bridge  102  causes the eyeglasses to move against the internal surfaces of the case and helps retain the eyeglasses in the case. 
         [0048]    An alternative embodiment of the eyeglasses is shown in  FIG. 9 . In this embodiment, the nose pads  600  are wider than the thickness of the lens  101 . The nose pads therefore are designed to fold for storage. For eyeglasses intended to be stored flat, the nose pads must fold to a thickness equal to or less than the thickness of the lenses. For eyeglasses intended to be stored in a folded configuration, the nose pads must fold to a thickness equal to or less than the combined thicknesses of the two lenses. 
         [0049]    For example, as shown in  FIG. 9 , the nose pad  600  is formed from a laminate  602  made from friction enhancing material and polycarbonate (0.01″ thick) and is attached to the bridge  601  at the top point. Nose pad  600  offers the same spring action described above (i.e., it has a spring constant less than the spring constant of bridge  102 ) but distributes the pinch force over a larger area. When stored, the nose pad folds along line  603  to become flat. 
         [0050]    Yet another configuration is shown in  FIG. 10 . Eyeglasses  1000  have lenses  1001  connected by a superelastic bridge  1002 . Nose pads  1009  with friction material facing the nose are connected to the lenses  1001  by nose pad carriers  1008  and super elastic torsion members such as nitinol wires  1011  (0.02″ diameter or less) and fold into the plane of the lenses when the lenses are inserted into a case or are folded flat against each other. The torsion element provides the spring force to engage the nose with the pad as well as torsion force to restore this orientation when withdrawn from a case thus making the glasses ultra compact and easy to store and carry. 
         [0051]    The embodiment shown in  FIG. 10  may be full size sunglasses having a 62 mm wide optical zone and weighing less than 7 g. The sunglasses may be stored in a flat configuration or in a folded configuration, as described above, in a case with an internal volume less than 10 cm 3 . 
         [0052]    The embodiment of  FIG. 10  also provides adjustable positions for the bridge  1002  and nose pads  1009  to accommodate a range of nose sizes for a comfortable and secure fit. Superelastic nitinol bridge  1002  is attached to two thin bridge carriers  1003  that can slide on the back surface of the lenses. Plastic or metal rivets  1006  whose heads are trapped by holes on the front of each lens penetrate serrated channels  1005  in the carriers  1003 . The rivets are attached to the nose pad carriers  1008  so that as the lenses are pushed toward each other the nose bridge narrows to accommodate narrower noses. 
         [0053]      FIG. 11  shows yet another embodiment of a flat glasses case  1101  attached to a housing  1103  via elastic connections  1105 ,  1106 ,  1107 , and  1108 . Housing  103  may be designed to attach to a cell phone. Elastic connections  1105 - 1108  permit the distance between case  1101  and housing  1103  to be increased to allow the user to use the space between the glasses case  1101  and the housing  1103  as a compact wallet carrying money, ID or credit cards  1104 .