Patent Publication Number: US-2013250231-A1

Title: Eyeglass earstem with enhanced performance

Description:
RELATED APPLICATION INFORMATION 
     The present application is a continuation of U.S. patent application Ser. No. 12/572,881, filed Oct. 2, 2009, the entirety of which is hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Field of the Inventions 
     The present disclosure relates generally to earstems for eyewear. More specifically, the present disclosure relates to methods and apparatuses for providing improved fit for eyewear. 
     2. Description of the Related Art 
     A wide variety of improvements have been made in recent years in the eyewear field, particularly with respect to eyewear intended for use in active sports or as fashion sunglasses. These eyewear designs accomplish a variety of functional advantages, such as maximizing interception of peripheral light, reducing optical distortion and increasing the wearer&#39;s comfort level, compared to previous active sport eyewear. 
     Lens geometry has also been the subject of a variety of innovations. The unitary lens of the Blades® eyewear incorporates the cylindrical geometry disclosed, for example, in U.S. Pat. No. 4,859,048, issued to Jannard. This geometry allows the lens to closely conform to the wearer&#39;s face and intercept light, wind, dust, etc. from directly in front of the wearer (anterior direction) and peripherally (lateral direction). See also U.S. Pat. No. 4,867,550 to Jannard (toroidal lens geometry). 
     In another important areas, eyeglass fit and comfort has generally been addressed by varying eyeglass frame size, minimizing eyeglass weight, modifying the manner in which earstems engage ears of the wearer, and utilizing nosepiece and ear-contacting materials that are comfortable for extended use, to name a few. 
     Eyeglass fit and comfort has been determined at least in part due to the material of which the eyeglass is made. For example, plastic or injection molded frame eyeglasses are often more flexible than metal frame eyeglasses, and therefore could provide lighter overall weight and greater flexibility than a metal frame eyeglass. Although metal frame eyeglasses have been improved in some ways, such as incorporating a spring overextension feature into the hinge connection of the earstem with the frame, the spring overextension feature is primarily useful in facilitating placement and mounting of the eyeglass on the head of the wearer. Such features may have moderately improved the flexibility and fit of plastic and metal frame eyeglasses; however, rigid frames and earstems do not provide any dynamic adjustment or flexibility. As such, prior art eyeglass designs do not adjust well over a range of head sizes and shapes. 
     SUMMARY 
     As noted above, one of the important areas for improvement in eyeglass designs is the area of improving the fit and comfort of the eyeglass. Various eyewear designs have been provided which reduce the weight of the eyeglass, allow the wearer to customize the fit of the eyeglass, or otherwise seek to alleviate pressure and discomfort during use. However, despite the many advances that have been made, there remains a need for a self-customizing eyewear design that can be worn on a variety of head sizes and shapes and eliminate lateral pressure on the temples. Further, there remains a need for a tunable earstem design that adjusts geometrically along its length to a corresponding head size and shape. In addition, there remains a need for an earstem design that enhances retention and performance of the eyeglass. 
     In particular, according to at least one of the embodiments disclosed herein is the realization that metal frame eyeglasses only provide limited adjustability for a wearer and usually do not achieve an optimal fit over a range of different head sizes and shapes. Although it is noted above that some prior art metal frame eyeglasses provide a spring overextension feature at the earstem hinge, the spring overextension feature is generally the only flexible part of the eyeglass because the earstems of metal frame eyeglasses are usually rigid. As such, a given metal frame eyeglass size may comfortably fit onto a narrow head and make it easier for a user to put the eyeglasses on. However, such an eyeglass generally has only a limited range of adjustability and flexibility and therefore only fits a very narrow range of head sizes and shapes. 
     Therefore, in accordance with at least one of the embodiments disclosed herein is the realization that metal frame eyeglasses can be improved by modifying the earstems such that the earstems exhibit flexural properties similar to those exhibited by a plastic or injection molded earstem. Further, some embodiments provide for a metal earstem that comprises one or more flex zones or points that allow the earstem to adjust to the natural and variable shape of a variety of head sizes and shapes. 
     Regardless of the material, some embodiments of the earstem can comprise one or more flex zones or points. The flex zones or points can be strategically configured to allow the earstem to provide a natural, versatile fit over a range of head shapes and sizes. For example, a first flex zone can extend along an initial anterior portion of the earstem, a second flex zone can extend along a middle portion of the earstem, and a third flex zone can extend along the anterior portion of the earstem. In particular, some embodiments are configured such that the first and second flex zones extend generally along an anterior half of the earstem while the third flex zone extends along a posterior half of the earstem. Further, some embodiments can be configured such that the number of flex zones or points is distributed evenly along the earstem. For example, three flex zones or points could be distributed along the anterior portion, the middle portion, and along the posterior portion of the earstem. The number of flex zones and locations of the same can be varied as desired. 
     The present disclosure enables the modification and adaptation of these principles to a variety of earstem shapes, sizes, and applications. 
     It is noted that although some embodiments are discussed as being made from metal, any of the embodiment disclosed herein can be made of metal, plastic, and/or composite materials. Thus, although many of the embodiments provide an effective solution to providing a metal earstem with enhanced performance, embodiments can also be made of plastic, composite, or combinations of materials. 
     Further, some embodiments can provide an earstem that uses a flexible spine or backbone and a motion-limiting apparatus. In some embodiments, the motion limiting apparatus can comprise one or more segments or components that are attached to or formed integrally or monolithically with the spine. 
     In some embodiments, the motion limiting apparatus can operate to limit motion of the spine through interference or contact between portions of the segment against the spine during deflection of the spine. For example, a segment can comprise a pocket or an area of relief into which the spine can deflect until contacting a bottom surface of the pocket or area of relief, thereby limiting motion of the spine. Further, in some embodiments, the motion limiting apparatus can operate to limit motion of the spine through interference or contact between adjacent segments. For example, the spine can deflect until adjacent segments are brought into contact with each other in such a manner than further deflection of the spine is prevented. These embodiments, and various other embodiments, are described and illustrated further herein. 
     Accordingly, the present inventions relate to a variety of earstem configurations that provide enhanced performance. The earstem can comprise at least one flexible portion and at least one relatively rigid portion that can each be modified to control one or more characteristics of the deflection of the earstem. Some of the characteristics of the deflection of the earstem can include the range of deflection, the number of deflection zones or points, the stiffness of the earstem, the deflection mode, and the structural constraints, to name a few. As a result, some of the embodiments disclosed herein can be implemented to provide an eyeglass that provides a customized to fit regardless of the wearer&#39;s head size or shape. 
     Some embodiments disclosed herein provide an eyeglass comprising a frame and an earstem attached to the frame. In some embodiments, the earstem can be fixedly attached to the frame. For example, the earstem may be formed monolithically with the frame or include a flexible point that allows limited movement of the earstem relative to the frame while preventing the earstem from being fully pivoted inwardly towards the frame to a stowed position. 
     In other embodiments, the earstem can be hingedly attached to the frame at a hinge joint that allows the earstem to be pivoted inwardly towards the frame to the stowed position. Hinge joint articulation may be limited by the flexibility and/or structure of the earstem. The hinge joint can be pretensioned or biased towards a given position. In embodiments wherein the earstem can be moved to a stowed position, the earstem can likewise be configured such that this joint allows flexibility from a deployed position in order to adjust for large or small head sizes and shapes. 
     Optionally, the earstem can include a plurality of discrete, flexible zones or points. Each of the zones or points can provide a degree of deflection for the earstem. Further, the arrangement and placement of the zones or points along the earstem can be configured to optimize the manner in which an earstem adjusts to a given head size and shape. In this regard, one or more flexible zones or points can be provided at one or more locations along the length of the earstem in a manner such that the earstem can be interchangeably worn and adjusted to a variety of head sizes and shapes while providing superior comfort and retention. 
     Further, in some embodiments, the earstem can optionally comprise a plurality of discrete segments or zones whereat the earstem is inflexible that are separated by a flexible zone or point. The length, geometry, and size of the segments can vary and may be configured to influence and/or control the motion, flexibility, and/or function of the earstem. For example, in some embodiments, the earstem can provide differential flexibility. In addition, in some embodiments, the earstem can provide a maximum range of movement or bending that is limited or controlled by interference between components of the earstem, such as the segments or spine or backbone of the earstem. For example, in some embodiments, the earstem can provide a range of motion that is limited by interference between a spine or backbone and a component of the earstem, such as a segment. The segment can comprise a pocket or area of relief into which the spine or backbone can deflect until contacting a bottom surface of the pocket or area of relief, which can then serve to prevent further deflection of the spine or backbone. In addition or in the alternative, the earstem can provide a range of motion that is limited by interference between segments of the earstem that contact each other such that further deflection is prevented due to interference or lack of clearance between segments of the earstem. Thus, in some embodiments, the displacement of components of the earstem can be limited at least partially due to interference between one or more components of the earstem. 
     Some embodiments provide for an earstem that comprises a metal spine and a plurality of segments that are attached to the spine. The metal can be titanium in some implementations. The segments can be fastened to the spine using fastening means such as mechanical fasteners including screws, bolts, etc. or other fastening means such as welding, adhesives, etc. The segments can be separated from each other along the spine. In some embodiments, one or more flex zones or points can be created along the spine. For example, a flex zone or point can be disposed between the spot at which the spine attaches to a frame of an eyeglass and the spot at which the spine attaches to a first segment disposed adjacent to the frame. Another flex zone or point can be disposed between another spot at which the spine attached to the first segment and a spot at which the spine attaches to a second segment. Further, yet another flex zone can be disposed along a tail, free end, or posterior end of the spine. In such embodiments, one or more of the segments can comprise a pocket or area of relief into which the spine can deflect until contacting a bottom surface of the pocket or area of relief, which can then serve to prevent further deflection of the spine. In addition or in the alternative, the earstem can provide a range of motion that is limited by interference between the frame and the first segment that contact each other, and/or the first and second segments of the earstem that contact each other, such that further deflection is prevented due to interference or lack of clearance between the first segment and the frame and/or between the first and second segments of the earstem. 
     Moreover, in some embodiments, the earstem can be configured to provide an undeflected position and one or more deflected positions. In such embodiments, the earstem can comprise one or more flexible zones or points and be configured such that one or more flexible zones or points are activated upon movement from the undeflected position to a deflected position or upon movement from a given deflected position to another give a deflected position. 
     Furthermore, in some embodiments, the earstem can be configured to comprise a uniquely configured hinge joint assembly that can be formed when the earstem is hingedly coupled to a frame of an eyeglass. For example, an anterior portion of the earstem can comprise a cam configured to bias the earstem in one of an open or deployed position and a closed or stowed position. In some embodiments, the cam can comprise a washer and a protrusion on the anterior portion of the spine that engages protrusions or recesses of the washer to be urged toward one or more rotational positions. 
     In some embodiments, the anterior portion of the spine can be split into upper and lower members. In such embodiments, the cam of the hinge joint assembly can be disposed at the lower member of the anterior portion of the spine. Further, by action of the cam, the upper and lower members of the anterior portion of the spine can be urged together when the earstem is moved away from the open position or away from the closed position. In this regard, the spine can be configured such that the urging together or deflection of the upper and lower members is a movement that is generally elastically resisted. Thus, when possible, the separation force of the upper and lower members will cause the earstem to be biased toward either the open position or the closed position. In addition, some embodiments can include a spring that acts as an assist to the separation force of the upper and lower members to urge them apart. In this manner, an initial force can be required to move the earstem from either the open or closed position, but as the earstem is pivoted, the cam action of the joint will cause that the earstem is naturally drawn into the other one of the open or closed position as it moves toward such position. 
     In accordance with an embodiment, an enhanced performance earstem is provided for eyeglasses. The earstem can comprise an elongate body and at least a first segment and a second segment on the body. The elongate body can have an anterior end and a posterior end. The first segment and the second segment can be separated by a flex zone or point. Further, a center of the flex zone or point can be within the range of from about 20 mm to about 70 mm from the anterior end of the elongate body. In some implementations, the center of the flex zone can be within the range of from about 25 mm to about 45 mm from the anterior end of the elongate body 
     In some implementations, the elongate body can deflect relative to at least a portion of one of the first and second segments. For example, one of the first and second segments can comprise a recess configured to receive at least a portion of the elongate body for allowing deflection of the elongate body relative to the respective one of the first and second segments. Further, the recess can comprise a contact surface configured to at least partially abut the elongate body for constraining deflection of the elongate body. A recess can be formed along one of the posterior and anterior portions of a given segment. It is also contemplated that a given segment can comprise a pair of recesses separated by an attachment zone whereat the elongate body attaches to the given segment. 
     Some implementations can also be provided wherein the first segment and the second segment are separated at the flex zone or point by at least a first gap. In this regard, deflection of the earstem at the flex zone or point can change a width of the first gap. For example, deflection of the earstem can be operative to reduce the first gap such that the first segment and the second segment contact each other to prevent further deflection of the earstem. The earstem can be configured to deflect at the flex zone or point until the first segment contacts the second segment. In some implementations, the earstem can be configured such that the first gap can separate the first segment and the second segment such that the first segment and the second segment do not touch when the earstem is in an undeflected position. 
     Optionally, the earstem can also be configured such that the flex zone or point can permit relative angular deflection of the first segment relative to the second segment within the range of from about 5° to about 40°. Further, the range can be within about 10° to about 20°. In some embodiments, the earstem can further comprise another flex zone or point, and the other flex zone or point can be disposed within the range of between about 30 mm to about 70 mm from the anterior end. Further, the other flex zone or point can be disposed within the range of between about 40 mm to about 60 mm from the anterior end, and in some cases, about 50 mm from the anterior end. 
     In some embodiments, the earstem can comprise three flex zones or points extending along the earstem. The flex zones may be separated from by one a relative rigid zone or point. It is also contemplated that the earstem can comprise four or more flex zones or points. 
     In some implementations, the first segment and the second segment can be disposed externally along the elongate body. The earstem can also be configured such that the first segment and the second segment can be formed separately from and coupled to the elongate body of the earstem. Moreover, the earstem can also be configured such that the first segment and the second segment can be generally rigid relative to the elongate body. 
     In another embodiment, an earstem is provided that can have differential flexibility. The earstem can comprise a flexible, elongate body having an anterior end and a posterior end. The body can have a plurality of relatively flexible zones. Each flexible zone can be separated from an adjacent flexible zone by a relatively rigid zone. Further, the relatively flexible zones can have different stiffnesses. 
     Some implementations of the earstem can be provided in which the stiffness of a first relatively flexible zone is greater than the stiffness of a second relatively flexible zone to provide progressive deflection of the earstem upon exertion of bending stress on the earstem. Further, the first relatively flexible zone can be disposed anteriorly relative to the second relatively flexible zone. 
     In some aspects, the earstem can be configured such that the first relatively flexible zone can finish deflecting before the second relatively flexible zone finishes deflecting. In this regard, the first relatively flexible zone can deflect prior to deflection of the second relatively flexible zone or both zones can deflect simultaneously. 
     Further, the elongate body, the rigid zones, and the flexible zones can be monolithically formed. Additionally, the earstem can be configured to further comprise an insert within the elongate body. The insert can comprise at least first and second relatively rigid segments separated by a relatively flexible zone. The earstem can optionally be configured such that the elongate body is comolded with the insert. Furthermore, the earstem can be configured such that at least one dimension of the elongate body remains generally constant between the anterior end and the posterior end of the earstem. 
     In accordance with some implementations, the earstem can be configured such that the relatively rigid zones each comprise at least one elongate segment. The relatively flexible zones can comprise at least one interconnector extending intermediate the elongate segments to interconnect the elongate segments in a general end-to-end manner to form at least first and second flex zones or points. Additionally, the elongate segments of the relatively rigid zones can be formed monolithically with each other and with the interconnectors of the relatively flexible zones. 
     In accordance with another embodiment, an earstem is provided that can be configured to provide an adjustable and personalized fit for an eyeglass. The earstem can comprise an elongate body and at least a first segment. The elongate body can define an anterior end that can be attached to the eyeglass and a posterior end that can extend rearwardly from the eyeglass. The at least first segment can be disposed along the earstem. The first segment can comprise a contact surface, and the contact surface can be positioned adjacent to the elongate body such that deflection of the elongate body causes relative movement between the contact surface and the elongate body. The contact surface can be configured to constrain deflection of the elongate body upon contact between the contact surface and the elongate body. The contact surface can permit relative movement between the first segment and the elongate body within a given range. 
     In some embodiments, the first segment can comprise another contact surface. Further, the contact surfaces can be separated by an attachment point whereat the first segment is coupled with the elongate body. Optionally, the earstem can comprise a second segment having a contact surface. Similar to the first segment, the second segment can be coupled to the elongate body such that the contact surface of the second segment serves to limit or restrain relative movement between the second segment and the elongate body. In some embodiments, the second surface limits or restrains movement between the second segment and the elongate body by contacting the elongate body. In other embodiments, it is contemplated that the second surface can limit or restrain movement between the second segment and the elongate body by contacting the first segment. 
     In yet another embodiment, an eyeglass is configured with earstems that can provide enhanced retention of the eyeglass on the head of a wearer. The eyeglass can comprise a frame and a pair of earstems. The frame can support at least one lens in the wearer&#39;s field of view. The pair of earstems can be attached to the frame for supporting the frame on the head of the wearer. Each earstem can comprise at least first and second flex zones or points whereat the earstems can bend. The first flex zone or point can provide a first degree of deflection, and the second flex zone or point can provide a second degree of deflection. In some implementations, the first degree of deflection can be different from the second degree of deflection such that the earstems provide progressive bending along a longitudinal axis of the earstems for providing a secure and conforming fit over a range of head sizes and shapes. 
     In accordance with some embodiments, the earstem can be configured such that the first degree of deflection can define a stiffness of the first flex zone or point and the second degree of deflection defines a stiffness of the second flex zone or point. Further, the first degree of deflection can define a maximum deflection of the earstem about the first flex zone or point and the second degree of deflection can define a maximum deflection of the earstem about the second flex zone or point. In this regard, it is contemplated that the earstems can comprise a plurality of segments being interconnected at the first and second flex zones or points. The maximum deflection of the earstem at a given flex zone or point can be limited by physical contact of adjacent segments at the given flex zone or point during deflection of the earstem at the given flex zone or point. 
     Some implementations of the earstem can be configured such that the earstem comprises a plurality of rigid segments with at least one segment extending generally between a first flex zone or point and a second flex zone or point of the earstem. Optionally, the rigid segments can be removably attachable to the earstem. Further, the rigid segments can comprise contact surfaces that are disposed adjacent to each other at the first and second flex zones or points, and the earstem can be configured such that deflection of the earstem is limited upon abutment of the contact surfaces of the adjacent segments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The abovementioned and other features of the inventions disclosed herein are described below with reference to the drawings of the preferred embodiments. The illustrated embodiments are intended to illustrate, but not to limit the inventions. The drawings contain the following figures: 
         FIG. 1  is a perspective view of an eyeglass in accordance with an embodiment of the present inventions. 
         FIG. 2  is a right side view of an earstem of the eyeglass of  FIG. 1 . 
         FIG. 3  is a top view of the earstem shown in  FIG. 2 . 
         FIG. 4  is a perspective view of an earstem segment or component, according to an embodiment. 
         FIG. 5  is an end view of the earstem segment or component shown in  FIG. 4 . 
         FIG. 6  is a cross-sectional top view of the earstem segment or component shown in  FIG. 4 , taken along lines  6 - 6  in  FIG. 4 . 
         FIG. 7  is a perspective view of another earstem segment or component, according to an embodiment. 
         FIG. 8  is an end view of the earstem segment or component shown in  FIG. 7 . 
         FIG. 9  is a cross-sectional top view of the earstem segment or component shown in  FIG. 7 , taken along lines  9 - 9  in  FIG. 7 . 
         FIG. 10A  is a top view of the earstem shown in  FIG. 2 , wherein the earstem is in an undeflected position. 
         FIG. 10B  is a top view of the earstem shown in  FIG. 2 , wherein the earstem is in a deflected position. 
         FIG. 11A  is a top cross-sectional view of the earstem shown in  FIG. 10A  which is taken along lines  11 A- 11 A of  FIG. 2 , wherein the earstem is in the undeflected position. 
         FIG. 11B  is a top cross-sectional view of the earstem shown in  FIG. 11A , wherein the earstem is in the deflected position. 
         FIG. 12  is a perspective view of an interior side and hinge joint of the eyeglass shown in  FIG. 1 . 
         FIG. 13  is an exploded perspective view of the interior side and hinge joint of the eyeglass shown in  FIG. 1 . 
         FIG. 14  is a bottom perspective view of an elongated body or spine of the earstem, according to an embodiment. 
         FIG. 15  is another bottom perspective view of the elongated body or spine shown in  FIG. 14 . 
         FIGS. 16-17  are perspective views of a cam member, according to an embodiment. 
         FIG. 18  is a perspective view of a washer, according to an embodiment. 
         FIG. 19  is a perspective view of a spring, according to an embodiment. 
         FIG. 20  is a perspective view of another eyeglass in accordance with another embodiment. 
         FIG. 21  is a left side view of an earstem of the eyeglass of  FIG. 20 . 
         FIG. 22  is a top view of the earstem shown in  FIG. 21 . 
         FIG. 23  is a left side view of an earstem, according to another embodiment. 
         FIG. 24  is a top view of the earstem shown in  FIG. 23 . 
         FIG. 25  is a top view a joint of an earstem wherein the joint is in an undeflected position, according to an embodiment. 
         FIG. 26  is a top view of the joint shown in  FIG. 25  wherein the joint is in a deflected position. 
         FIG. 27  is a top view another joint of an earstem wherein the joint is in an undeflected position, according to another embodiment. 
         FIG. 28  is a top view of the joint shown in  FIG. 27  wherein the joint is in a deflected position. 
         FIG. 29  is a left side view of an earstem of an eyeglass, according to another embodiment. 
         FIG. 30  is a top view of the earstem shown in  FIG. 29 . 
         FIG. 31  is a left side view of another earstem of an eyeglass, according to yet another embodiment. 
         FIG. 32  is a top view of the earstem shown in  FIG. 31 . 
     
    
    
     DETAILED DESCRIPTION 
     While the present description sets forth specific details of various embodiments, it will be appreciated that the description is illustrative only and should not be construed in any way as limiting. Additionally, it is contemplated that although particular embodiments of the present inventions may be disclosed or shown in the context of dual lens eyewear systems, embodiments can be used in both unitary and dual lens eyewear systems. Further, it is contemplated that although particular embodiments of the present inventions may be disclosed or shown in the context of frames having full orbitals, such embodiments can be used with frames having full or partial orbitals or rimless frames. Furthermore, various applications of such embodiments and modifications thereto, which may occur to those who are skilled in the art, are also encompassed by the general concepts described herein. 
     As discussed above, embodiments disclosed herein are operative to provide adjustability and optimal fit over a wide range of different head sizes and shapes. Accordingly, an eyeglass can be fabricated using metals or other stiff materials that may have desirable properties while nevertheless enabling the eyeglass to provide desirable flexural properties in the earstems thereof. For example, titanium, carbon fiber, aluminum, and other such materials provide superior mechanical properties while reducing the weight of the eyeglass. Indeed, metals or other rigid materials can be used to form the eyeglass, thus providing exceptional rigidity, durability, and wear resistance. However, prior to the development of the embodiments disclosed herein, and eyeglass made of such rigid materials would function very poorly in accommodating a wide range of head sizes and shapes. Thus, various embodiments disclosed herein enable the use of rigid materials such as metals, composites, and the like in eyewear while providing earstem flexibility that was previously unavailable in the eyeglass is made of such materials. 
     Thus, various embodiments are provided in which the eyeglass has a metal frame and is operative to provide superior adjustability and flexibility over a wide range of head sizes and shapes, as could be possible with a plastic eyeglass. Nevertheless, various features and aspects disclosed herein can be used in eyeglasses fabricated from any material, whether the eyeglass is made from plastic, composite, metal, or any combination thereof. 
     Therefore, in accordance with at least one of the embodiments disclosed herein is the realization that metal frame eyeglasses can be improved by modifying the earstems such that the earstems exhibit flexural properties similar to those exhibited by a plastic or injection molded earstem. Further, some embodiments provide for a metal earstem that comprises one or more flex zones or points that allow the earstem to adjust to the natural and variable shape of a variety of head sizes and shapes. 
     Regardless of the material, some embodiments of the earstem can comprise one or more flex zones or points. The flex zones or points can be strategically configured to allow the earstem to provide a natural, versatile fit over a range of head shapes and sizes. For example, a first flex zone can extend along an initial anterior portion of the earstem, a second flex zone can extend along a middle portion of the earstem, and a third flex zone can extend along the anterior portion of the earstem. In particular, some embodiments are configured such that the first and second flex zones extend generally along an anterior half of the earstem while the third flex zone extends along a posterior half of the earstem. Further, some embodiments can be configured such that the number of flex zones or points is distributed evenly along the earstem. For example, three flex zones or points could be distributed along the anterior portion, the middle portion, and along the posterior portion of the earstem. The number of flex zones and locations of the same can be varied as desired. 
     The present disclosure enables the modification and adaptation of these principles to a variety of earstem shapes, sizes, and applications. 
     As noted above, although some embodiments are discussed as being made from metal, any of the embodiments disclosed herein can be made of metal, plastic, and/or composite materials. Thus, although many of the embodiments provide an effective solution to providing a metal earstem with enhanced performance, embodiments can also be made of plastic, composite, or combinations of materials. 
     Further, in addition to addressing many problems associated with eyeglasses made of rigid materials, the teachings and disclosure herein also enable a personal skill in the art to design an eyeglass having desirable aesthetic properties and later construct an exceptional functional platform that provides superior comfort and adaptability for wearers. In other words, embodiments disclosed herein enable the function of the eyeglass to follow the form of the eyeglass, rather than having the form or design of the eyeglass be dictated by the function thereof. This and other novel features of the embodiments disclosed herein provide an exceptional advance in the eyewear industry. 
     In the present description, various mechanical terms are used in reference to deformation and/or other structural characteristics of components of the embodiments disclosed herein. As used herein, term “stiffness” or “bending stiffness” can be defined as the resistance of an elastic body to deformation by an applied force. In this regard, stiffness is not the same as the “flexural or elastic modulus”; stiffness relates to a property of a solid body and flexural or elastic modulus relates to a property of a material of the solid body. 
     In other words, stiffness is a property of the solid body that is dependent on the material and the shape and boundary conditions. See Wikipedia, “stiffness.” For example, with reference to embodiments disclosed herein, the bending stiffness “EI” of an earstem relates the applied bending moment to the resulting deflection of the earstem. The bending stiffness is the product of the elastic modulus “E” of the earstem material and the area moment of inertia “I” of the earstem cross-section. Further, when a plurality of components or components comprising a plurality of materials is used in the earstem, the equation is modified accordingly to account for the individual components and material variations. In a basic scenario, according to elementary beam theory, the relationship between the applied bending moment M and the resulting curvature κ of the beam is: 
     
       
         
           
             M 
             = 
             
               
                 EI 
                  
                 
                     
                 
                  
                 κ 
               
               = 
               
                 EI 
                  
                 
                   
                     
                        
                       2 
                     
                      
                     ω 
                   
                   
                      
                     
                       x 
                       2 
                     
                   
                 
               
             
           
         
       
     
     where w is the deflection of the beam and x the spatial coordinate. Accordingly, as will be apparent to one of skill in the art, the bending stiffness of embodiments of the earstem can be measured using the principles discussed above. 
     Referring now to the figures, wherein embodiments are shown for purposes of illustrating features of the present inventions, and not for limiting the same,  FIG. 1  illustrates an embodiment of an eyeglass  10  prepared in accordance with an aspect of the present inventions. The eyeglass  10  comprises a first earstem  12  and a second earstem  14 . In the illustrated embodiment, the first and second earstems  12 ,  14  are attached to a frame  16  of the eyeglass  10  at respective first and second joints  20 ,  22 . The first and second joints  20 ,  22  can enable the earstems  12 ,  14  to be selectively pivoted between a stowed position and a deployed position. As illustrated in  FIG. 1 , the earstems  12 ,  14  are positioned in the deployed position, ready for use. 
     The eyeglass  10  can further comprise one or more earstem bend control components. For example, referring to  FIGS. 2-3 , the first earstem  12 , the first earstem  12  can comprise one or more segments  30 ,  32 . In some embodiments, the segments  30 ,  32  can be formed monolithically with the first earstem  12 . However, in other embodiments, the segments  30 ,  32  can be attached to a flexible, elongate body, spine, or backbone  34 . As illustrated in  FIG. 2 , these segments  30 ,  32  can be attached to the body  34  using one or more mechanical fasteners  40 . In this regard, the first earstem  12  can be flexible to the degree permitted by the segments  30 ,  32 . 
     Further, as shown in  FIG. 3 , the segments  30 ,  32  can also form one or more flexible zones or points,  42 ,  43 ,  44 , whereat the first earstem  12  can bend. In the illustrated embodiment, a first flexible zone or point  42  is formed between the joint  20  and an anteriorly located first fastener  40 ′. A second flexible zone or point  43  is formed between a second fastener  40 ″ and a third fastener  40 ″′. A third flexible zone or point  44  is formed between the third fastener  40 ″′ and a posterior end  46  of the earstem  12 . 
     In this regard, as used herein, the term “zone” or “point” can be used to refer generally to the location along an earstem at which the earstem bends or deflects. In some embodiments, the point of deflection can be at a joint formed between two structures, and the joint can comprise that deflection point where the structures are made of a common or separate material, or whether the structures are comolded, coupled together, or monolithically formed. A deflection zone of the earstem can be formed along that portion of the spine or backbone that is not constrained against bending. In some embodiments, deflection zones or points can be separated by zones or points where the spine or backbone is constrained against deflection. 
     In addition, in the various embodiments disclosed herein, it is contemplated that the flex zones or points should be configured such that deflection at a given flex zone or point does not permit the flex zone or point to undergo a stress that is greater than the yield stress of that material. For example, the earstem can be configured such that the allowable stress is less than about 70% of the yield stress of the material. Further, the earstem can be configured such that the allowable stress is less than about 50% of the yield stress of the material. Moreover, the earstem can be configured such that the allowable stress is between less than about 30-50% of the yield stress of the material. 
     For example, an elongate body or spine, whether formed separately or monolithically with other components, can be configured to undergo bending stresses in order to permit deflection of the ear stem. As noted above, the elongate body or spine should be configured such that the allowable bending stresses remain within an acceptable or under an acceptable percentage of the yield stress of the elongate body or spine. Further, stress concentrations at given flex zones or points should be minimized such that stresses are distributed to avoid failure. In this regard, it is contemplated that one of skill in the art can design the ear stem such that a stresses exerted on any given component stay within an acceptable range below the yield stress during use of the eyeglass. 
     In the illustrated embodiment of  FIGS. 1-19 , the flexible zones represent those areas along which the body  34  of the earstem  12  can bend or deflect. Other areas of the body  34  can be constrained against deflection, such as the portion of the body  34  located between the first and second fasteners  40 ′,  40 ″. These features and the advantages thereof are discussed in greater detail below. 
     In accordance with another aspect of the embodiment illustrated  FIGS. 1-19 , the segments  30 ,  32  can comprise one or more contact surfaces that are configured to assist in limiting and/or controlling deflection of the earstem  12 . For example, as discussed below with reference to  FIGS. 4-11B , the body or spine  34  of the earstem  12  can be a loud to deflect within a given range until contacting a surface of one of the segments  30 ,  32 . Upon contact with the surface, the body or spine  34  will be constrained against further deflection, thus constraining the earstem  12  against deflection as well. In some embodiments, the contact surfaces of the segments  30 ,  32  can be formed on an interior side of the segments  30 ,  32 . 
     For example, referring now to  FIGS. 4-6 , an embodiment of the second segment  32  is shown in a perspective, a side, and a cross-sectional top view. The second segment  32  can comprise a first contact surface  50 , an attachment portion  100 , and a recess, pocket, or area of relief  102 . In this regard, the attachment portion  100  of the second segment  32  can be configured to attach with and/or receive at least a portion of the body  34  such that the second segment  32  can be mounted onto the body  34 . For example, the second segment  32  can be mounted onto the body or spine  34  of the earstem  12  using a fastener, such as a bolt or screw which can be passed through the body or spine  34  and attached to the attachment portion  100  of the second segment  32 . 
       FIG. 6  illustrates a the cross-sectional top view of the second segment  32  in which the recess  102  widens from a recess of the attachment portion  100  such that the body  34  can be laterally deflected relative to the second segment  32 . Thus, upon attachment to the body  34 , an upper surface  104  of the attachment portion  100  will abut and (along with the fastener used to attach the second segment  32  to the body  34 ) constrain the corresponding portion of the body  34  from movement while a length or portion of the body  34  adjacent to the recess  102  is unconstrained. Thus, due to the presence of the recess  102 , a portion of the body  34  will be generally unconstrained against deflection along the anterior portion  106  of the second segment  32 . In other words, the body  34  can be rigidly attached to the second segment  32  at the attachment portion  100  while being able to deflect into the recess  102  formed at the anterior portion  106  of the second segment  32 . However, it is noted that a top surface  110  of the recess  102  can serve to constrain lateral deflection of the body  34 . As such, the configuration and geometry of the recess  102  and the top surface  110  can be selectively configured to allow a desired degree of lateral deflection of the body  34 . 
     With reference now to  FIG. 7-9 , an embodiment of the first segment  30  is shown in a perspective, a side, and a cross-sectional top view. The first segment  30  can comprise a second contact surface  52  and a third contact surface  54 . The second contact surface  52  can be disposed along a posterior end  120  of the first segment  30 , and the third contact surface  54  can be disposed along and anterior end  122  of the first segment  30 . The first segment  30  can also comprise an attachment portion  130  and at least one recess, pocket, or area of relief. In some embodiments, the attachment portion  130  can be disposed along a central portion of the first segment  30 . However, it is also contemplated that the attachment portion can be located along either the posterior or anterior portions  120 ,  122  of the first segment  30 . 
     As discussed above with respect to the second segment  32 , the attachment portion  130  of the first segment  30  can be configured to attach with or receive at least a portion of the body  34  such that the first segment  30  can be mounted onto the body  34 . For example, the first segment  30  can be mounted onto the body or spine  34  of the earstem  12  using a fastener, such as a bolt or screw which can be passed through the body or spine  34  and attached to the attachment portion  130  of the first segment  30 . 
     Further, the first segment  30  can comprise an anterior protrusion  160 . The anterior protrusion  160  can be disposed intermediate the upper and lower fork members (discussed further below) of the body or spine  34 .  FIGS. 11A-B  also illustrate the movement of the segment  32  relative to the body or spine  34 , which movement is easier to see noting the position of the protrusion  160  relative to the body or spine  34 . 
     Further, as shown in the illustrated embodiment, the first segment  30  can comprise an anterior recess  132  and a posterior recess  134 . Similar to the recess  102  of the second segment  32 , the anterior and posterior recesses  132 ,  134  can be configured to allow the body  34  to deflect relative to the first segment  30 . In this regard, once the first segment  30  is mounted onto the body  34 , the body  34  can deflect into either of the anterior or posterior recesses  132 ,  134 . 
     For example, with reference to  FIG. 9 , the recesses  132 ,  134  both widen from a recess of the attachment portion  130  such that the body  34  can be laterally deflected relative to the first segment  30 . Thus, upon attachment to the body  34 , an upper surface  140  of the attachment portion  130  will abut and (along with one or more fasteners used to attach the first segment  30  to the body  34 ) constrain the corresponding portion of the body  34  from movement while a length or portion of the body  34  adjacent to the recesses  132 ,  134  are unconstrained from movement. 
     Thus, due to the presence of the recesses  132 ,  134 , portions of the body  34  will be generally unconstrained against deflection along the anterior and posterior portions  120 ,  122  of the first segment  30 . In other words, the body  34  can be rigidly attached to the first segment  30  at the attachment portion  130  while being able to deflect into the recesses of  132 ,  134  formed at the respective ones of the anterior and posterior portions  120 ,  122  of the first segment  30 . However, it is noted that a top surface  150  of the recess  132  and a top surface  152  of the recess  134  can serve to constrain lateral deflection of the body  34 . As such, the configuration and geometry of the recesses  132 ,  134  and the top surfaces  150 ,  152  can be selectively configured to allow a desired degree of lateral deflection of the body  34 . 
     Accordingly, the embodiment illustrated in  FIGS. 1-19  can be configured to allow the body or spine  34  to deflect relative to the first and second segments  30 ,  32 . Further, the movement and/or deflection of the body  34  can also be limited and/or controlled by the first and second segments  30 ,  32 . 
       FIGS. 10A-B  illustrate the first earstem  12  in an undeflected position (shown in  FIG. 10A ) and a deflected position (shown in  FIG. 10B ). As shown, the first and second segments  30 ,  32  serve to limit the lateral deflection of the body  34  along the initial or anterior half of the earstem  12 . As noted above, the first and second flex zones or points  42 ,  43  shown in  FIG. 3  lie generally within the initial or anterior half of the earstem  12 . In this regard, the third flex zone  44  comprises the posterior half of the earstem  12 . Accordingly, the deflection of the posterior half of the earstem  12  will generally be dictated by the geometry and material properties of the body or spine  34  in this embodiment. Thus,  FIGS. 10A-B  illustrate how the earstem  12  can accommodate a variety of head sizes and shapes. 
     Optionally, in some embodiments, it is contemplated that the first and second contact surfaces  50 ,  52  of the respective ones above the first and second segments  30 ,  32  can be configured to limit and/or control deflection of the earstem  12 . In this regard, it is contemplated that deflection of the earstem  12  can be restrained at the flexible zone or point  43  due to the interaction between the first and second contact surfaces  50 ,  52 . In other words, the first earstem  12  can be restrained from further medial bending beyond a given range due to interference or contact between the first and second segments  30 ,  32 . 
     For example, the deflection of the first earstem  12  can be controlled and/or limited by adjusting the geometry and/or spacing of the first and second contact surfaces  50 ,  52  of the segments  30 ,  32 . The first and second segments  30 ,  32  can be spaced apart by a gap  60  in the undeflected position, and the earstem  12  can be configured such that the gap  60  closes as the first earstem  12  moves from the undeflected position to the deflected position. When the gap  60  is completely closed, the contact surfaces  50 ,  52  of the first and second segments  30 ,  32  can abut each other and prevent further deflection of the earstem  12  in the second flex zone  43 . The gap  60  can therefore correspond at least in part to an initial or primary degree of permissible deflection that can be made between the segments  30 ,  32  of the first earstem  12 . The size of the gap  60  can be varied in order to provide a desired initial or primary degree of deflection at the flexible zone or point  43 . 
     In accordance with another unique aspect of some embodiments, the first and second contact surfaces  50 ,  52  can also be arcuately formed. As a result, some embodiments of the first and second contact surfaces  50 ,  52  can engage each other not only to limit further medial bending of the first earstem  12 , but to also limit torsional or vertical bending of the first earstem  12  at the flexible zone or point  43 . 
     In accordance with another aspect of the embodiment shown in  FIGS. 1-19 , it is contemplated that the flex zones can be located at a given distance from an anterior end  45  of the earstem  12 , such as the joint  20 . In other words, the flex zones can be distributed along the first earstem  12  intermediate the anterior end  45  and a posterior end  46 . The first earstem  12  can be configured to optimize the length and/or location of the flex zones. 
     For example, as discussed above with respect to  FIG. 3 , the first flex zone  42  can extend between the joint  20  and the fastener  40 ′. The second flex zone  43  can extend between the fastener  40 ′ and the fastener  40 ″. The third flex zone  44  can extend between the fastener  40 ″′ and the posterior end  46  of the earstem  12 . It is contemplated that the length and location of the flex zones  42 ,  43 ,  44  can be modified by changing the location of the fasteners in the disclosed embodiment. Further, the space between the fasteners  40 ′ and  40 ″ can also be modified to adjust the length of an inflexible zone of the body or spine  34 . 
     It will be appreciated that the length and/or location of the flexible zones of the earstem  12  can determine the deflected shape or contour of the first earstem  12 . For example, the first flex zone  42  can be configured to extend along the anterior half of the earstem  12 . Specifically, the first flex zone  42  can extend along the anterior one third section of the earstem  12 . In some embodiments, the first flex zone  42  can be configured to extend from the joint  20  and have a length of between about 10 mm to about 30 mm. In the illustrated embodiment, the length of the first flex zone  42  is approximately 20 mm. 
     Further, the second flex zone  43  can be configured to extend along the anterior two-thirds portion of the earstem  12 . In particular, the first flex zone  42  and the second flex zone  43  can collectively extend along the anterior half section of the earstem  12 . In some embodiments, the second flex zone  43  can begin at a distance of between about 10 mm to about 40 mm from the joint  20  and can have a length of between about 10 mm to about 30 mm. Thus, a center of the second flex zone  43  can be about 20 mm to about 70 mm from the joint  20 . In the illustrated embodiment, the second flex zone  43  begins at about 25 mm from the joint  20  and has a length of about 20 mm. 
     Finally, the third flex zone  44  can be configured to extend along the posterior two thirds portion of the earstem  12 . In particular, the third flex zone  44  can extend at least along the posterior half section of the earstem  12 . In some embodiments, the third flex zone  44  can begin at a distance of between about 30 mm to about 70 mm from the joint  20  and can have a length of between about 40 mm to about 120 mm. In the illustrated embodiment, the third flex zone  43  begins at about 45 mm from the joint  20  and has at length of about 90 mm. 
     Similarly, as shown in  FIG. 2 , a posterior end  47  of the second segment  32  can be spaced at a length or distance from the joint  20 . Further, the interconnection of the second segment  32  with the body  34  and the shape of the second segment  32  can be selected to constrain movement of the body  34  adjacent to the second segment  32 . It is contemplated that the elongate body  34  of the first earstem  12  may tend to deflect at the posterior end  47  of the second segment  32 . This deflection is similar to that which may occur at the flexible zone or point  42  and the joint  20  in that the configuration of the end  47  and the presence or absence of a recess can determine whether and how much the body  34  is permitted to deflect. As such, the length or distance of the end  47  from the joint  20  can be modified similarly to the length or distance of the fastener  40 ′ from the joint  20 , as regards the first segment  30 . In this regard, the end  47  can be spaced at approximately the middle one-third section of the earstem  12 . More specifically, the end  47  can be spaced at approximately the midpoint of the earstem  12 . In some embodiments, the length or distance of the end  47  from the joint  20  can optionally be configured to be between about 30 mm to about 70 mm. In the illustrated embodiment, the length or distance of the end  47  from the joint  20  is approximately 50 mm. 
     The location of flexible zones or points can be modified in order to allow the earstem to have desirable bending characteristics. For example, it is contemplated that the flexible zones or points can be spaced at equal lengths along the earstem. Further, it is contemplated that the flexible zones or points can be spaced at increasingly shorter lengths along the earstem. In this manner, the geometry of the earstem can be selectively configured to produce a given shape, deflected position, or bending mode. Various embodiments and illustrations of this principle are shown and described herein. 
     The above-disclosed ranges of lengths and locations of the flexible zones can be incorporated into various embodiments of the earstem disclosed herein. However, it is contemplated that the number of flexible zones can also be modified by one of skill in the art. Additionally, as discussed herein, the dimensions and material properties of the body or spine and any segment of the earstem can also be selected were modified by one of skill in the art to produce an earstem having desirable flexural and geometric properties. 
       FIG. 11A  is a top cross-sectional view of the earstem  12  shown in the top view of  FIG. 10A  while in the undeflected position.  FIG. 11B  is a top cross-sectional view of the earstem  12  shown in the top view of  FIG. 10B  while in the deflected position. With initial reference to  FIG. 11A , the body or spine  34  is attached to the first and second segments  30 ,  32  at the respective ones of the attachment portions of  100 ,  140 . Notably, the recesses  132 ,  134 , and  102  are provided such that the body or spine  34  can deflect. As discussed above, the surfaces  150 ,  152 , and  110  provide a means for limiting and/or controlling deflection of the body or spine  34 . 
     Referring now to  FIG. 11B , the earstem  12  is shown in a deflected position in which the body or spine  34  has deflected. In particular, the body or spine  34  has moved from a generally curved configuration to a straighter configuration. However, it is contemplated that the shape of the body or spine  34  can be modified in either the undeflected or deflected positions.  FIG. 11B  also illustrates that the body or spine  34  can be at least partially deflected into the recesses of the first and second segments  30 ,  32 . Further, the surfaces  150 ,  152 , and  110  can serve to prevent further deflection and/or control the deflection of the body or spine  34 . As illustrated, the body or spine  34  can abut the surfaces  150 ,  152 , and  110  in the deflected position. 
     The illustrated embodiment of  FIGS. 1-19  can also provide a manner of dynamically controlling and/or limiting the motion of the first earstem  12 . In this regard, the stiffness of the first earstem  12  can be selectively controlled based on the dimensions and materials used for the joints, elongate body, and segments of the first earstem  12 . 
     For example, in addition to the initial degree of deflection relating to the gap  60 , it is also contemplated that the elongate body  34  of the first earstem  12  can permit a further or secondary degree of deflection. In this regard, the elongate body  34  of the first earstem  12  can be formed from an elastic material that allows the portion of the elongate body  34  to be stretched in tension after the first earstem  12  deflects according to the initial degree of deflection corresponding to the size of the recesses, or in some embodiments, the gap between contact surfaces of adjacent segments. 
     As shown in  FIG. 2 , a length  62  of the elongate body  34  can be positioned between the mechanical fasteners  40  that attach the segments  30 ,  32  to the elongate body  34 . In some embodiments, the body or spine  34  can be dimensions to control the stiffness of the length  62 . In other words, one of skill in the art can take into account the flexural or elastic modulus of the material of the body or spine  34  with the cross-sectional dimensions of the body or spine  34  along the length  62  in order to provide desirable bending characteristics of the elongate body or spine  34  along the length  62 . Embodiments wherein the body or spine  34  is fabricated from a metal or composite can be especially benefited by such an analysis. 
     It is contemplated that the body or spine  34  can be configured such that the length  62  of the elongate body  34  can provide a further or secondary degree of deflection for the first earstem  12 . For example, the body or spine  34  can he made of an elastic material such that as the length  62  stretches, thus allowing at least limited further deflection about the flexible zone or point  42 . It is therefore contemplated that the material and/or geometry of the elongate body  34  can be selected to provide a desired secondary degree of deflection about the flexible zone or point  42 . Therefore, as the length  62  stretches, the force required to cause additional deflection can be dynamically increased. 
     Referring again to  FIGS. 10A-B  in accordance with some embodiments, the first segment  30  can comprise the third contact surface  54  and the frame  16  can comprise a fourth contact surface  56 . Optionally, it is contemplated that the third and fourth contact surfaces  54 ,  56  can define a gap  64  that can correspond to an initial or primary degree of deflection at the joint  20 . In optional embodiments, the third contact surface  54  can interact with the fourth contact surface  56  to limit and/or control movement of the earstem  12 . For example, the third contact surface  54  and the fourth contact surface  56  can abut each other, similar to the optional embodiment disclosed above with respect to the first and second contact surfaces  50 ,  52 , such that the third and fourth contact surfaces  54 ,  56  can provide stability and further control and/or limit the deflection of the first earstem  12 . In this regard, the third and fourth contact surfaces  54 ,  56  can be arcuately formed. In this manner, the third and fourth contact surfaces  54 ,  56  can engage each other to not only limit further medial bending of the first earstem  12 , but to also limit torsional or vertical bending of the first earstem  12  at the joint  20 . 
     Optionally, in such embodiments, in addition to the initial degree of deflection relating to the gap  64 , it is also contemplated that the elongate body  34  of the first earstem  12  can permit a further or secondary degree of deflection at the joint  20 . For example, the elongate body  34  of the first earstem  12  can be formed from an elastic material that allows the portion of the elongate body  34  to be stretched in tension after the first earstem  12  deflects according to the initial degree of deflection corresponding to the size of the gap  64 . Specifically, as shown in  FIG. 2 , a length  66  of the elongate body  34  can be positioned between a pin  68  of the joint  20  and the mechanical fastener  40 ′ that attach the segment  32  to the elongate body  34 . Accordingly, the length  66  of the elongate body  34  can provide a further or secondary degree of deflection for the first earstem  12  as the length  66  stretches, thus allowing at least limited further deflection about the joint  20 . It is therefore contemplated that the material and/or geometry of the elongate body  34  can be selected to provide a desired secondary degree of deflection about the joint  20 . Therefore, as the length  66  stretches, the force required to cause additional deflection can be dynamically increased. 
     As noted above, in embodiments wherein the body or spine  34  is formed from a metal or composite, one of skill in the art can take into account the flexural or elastic modulus of the material of the body or spine  34  with the cross-sectional dimensions of the body or spine  34  along the length  66  in order to provide desirable bending characteristics of the elongate body or spine  34  along the length  62 . Embodiments wherein the body or spine  34  is fabricated from a metal or composite can be especially benefited by such an analysis. 
     As will be appreciated with reference to  FIGS. 1-11B , the illustrated embodiment can also provide a manner of progressively controlling and/or limiting the motion of the first earstem  12 . In this regard, the stiffness of the first earstem  12  can be selectively controlled based on the dimensions and materials used for the flexural zones, elongate body or spine, and segments of the first earstem  12 . 
     For example, it is contemplated that the earstem can comprise more than two segments. In such embodiments, the earstem can comprise a plurality of flexible zones or points disposed between the segments of the earstem. Optionally, the flexible zones or points of such embodiments could also comprise gaps formed between the segments. In some embodiments, relative movement between adjacent segments can serve to close the gaps, thereby limiting the initial or primary degree of deflection at the zones or points. Optionally, the zones or points can provide a further or secondary degree of deflection relating to tensile bending or stretching of an elastic body or spine. 
     Moreover, embodiments can be to enable progressive or controlled deflection of the earstem  12 . In particular, it is contemplated that one or more recesses formed in a segment attached to the body or spine of the earstem can limit and/or control deflection of the body or spine. Further, in optional aspects, gaps can be formed between the segments of the earstem and selectively dimensioned in order to allow progressive deflection of the earstem. 
     For example, in an embodiment wherein the earstem has first, second and third flexible zones or points, the earstem could begin deflecting at the first zone or point prior to deflection of the second and third zones or points. In particular, it may be beneficial to allow the anterior or first zone or point to deflect initially when the first zone or point is disposed anteriorly relative to the second and third zones or points. Subsequent to the deflection at the first zone or point, the second zone or point can begin deflecting. Then, subsequent to deflection at the second zone or point, the third zone or point can begin deflecting. Thus, the earstem can be configured such that each zone or point at least partially deflects prior to deflection of a subsequent zone or point. In some embodiments, deflection at a given zone or point may be completed prior to the beginning of deflection at the subsequent zone or point. In other words, the earstem can reach maximum deflection at the first zone or point before beginning to deflect at the second zone or point, and the earstem can then reach maximum deflection at the second joint before beginning to deflect at the third zone or point. As such, various embodiments of the earstem disclosed herein can not only provide progressive deflection, but can provide partial or complete progressive deflection. 
     Nevertheless, it is contemplated that in some embodiments, the flexible zones or points of the earstem can provide proportional and/or simultaneous deflection. 
     With further reference to the embodiment shown in  FIGS. 1-19 , the segments  30 ,  32  can be configured as rigid components of the first earstem  12 . However, it is contemplated in some embodiments, that one or more segments can be flexible, and can provide dynamic deflection of the earstem based on the segment geometry and material. 
     Further, as shown in the illustrated embodiment of  FIGS. 1-19 , the segments  30 ,  32  can be formed separately from the elongate body  34  of the first earstem  12 , and the segments  30 ,  32  can be generally rigid components that are attached to a relatively flexible elongate body  34 . However, embodiments are contemplated in which the segments are formed monolithically with the earstem, spaces, joints, or gaps between the segments and the frame and/or the remainder of the first earstem can be dimensioned in order to provide flexibility relative to the segments. 
     Even in such diverse embodiments, the earstem can comprise a variable or constant stiffness along its length and/or one or more deflection modes. For example, in a first deflection mode, the elongate body can bend at spaces, joints, or gaps between the segments and the frame and/or the remainder of the earstem. Further, in some embodiments, in a second deflection mode, the elongate body can be stretched or deformed in tension. Furthermore, in some embodiments, in a third deflection mode, these segments can be deflected themselves in order to allow a further degree of deflection of the first earstem. The stiffness of the earstem can vary along the length thereof, at given zones or points, in order to modify the deflection mode, including the progression of deflection. 
     Referring now to  FIG. 12 , a perspective view of an interior portion of the assembled earstem  12  and eyeglass  10  are shown. Further,  FIG. 13  illustrates, in perspective, and exploded view of the joint  20  of the eyeglass  10 . As illustrated and discussed below, the joint  20  can be configured to comprise a cam-assist closure mechanism. 
     As shown in  FIG. 13 , the joint  20  can be formed from an anterior portion or end  200  of the body or spine  34 , a washer  202 , and elongate pin  204 , a spring  206 , and a cam member  208 . These components can be received or mounted at a lateral side  210  of the frame  16 . In particular, the frame  16  can comprise a recessed area  212  having upper and lower components  214 ,  216  that can engage to pin  204  in order to retain the above-noted components and thereby form the joint  20 . 
     One of the unique aspects of embodiments of the joint  20  is that the joint can comprise a cam-assist closure mechanism. In this regard, the cam-assist closure mechanism can comprise one or more protrusions formed on the anterior portion  200  of the body or spine  34  that can interact with the cam member  208 . 
     For example, with reference to  FIG. 14 , the anterior portion  200  of the elongate body or spine  34  can comprise upper and lower fork members  240 ,  242 . In some embodiments, is one of the fork members  240 ,  242  can comprise a projection or recess that can be configured to interact with the cam member  208 . As illustrated in  FIG. 14 , the lower fork member  242  can comprise a pair of projections  250  that extend downwardly from a pin mounting component  252  of the lower fork member  242 . 
     Additionally, as discussed above, the body or spine  34  can define a variable cross-sectional profile in order to provide a given stiffness at a given point along the length of the body or spine  34 . In the embodiment illustrated in  FIGS. 14-15 , the dimensions of the body or spine  34  can vary in width or thickness. For example,  FIG. 14  illustrates that the body or spine  34  can have a width that varies along the length thereof. Notably, the body or spine  34  can comprise an area or zone  260  of increased stiffness which is formed by increasing the width of the body or spine  34  in that area  260 . Moreover,  FIG. 15  illustrates that the thickness of the body or spine  34  can be varied as well. For example, the thickness of the body or spine  34  along the anterior portion  200  thereof is reduced compared to the thickness of the body or spine  34  in other areas thereof. In this regard, the stiffness at any given point along the anterior portion  200  of the body or spine  34  will be a summation of the stiffnesses of the individual upper and lower fork members  240 ,  242 . Accordingly, in order to provide it desirable flexural properties, the thickness and/or width of the body or spine  34  can be varied in various embodiments. 
     One of the unique aspects of some embodiments disclosed herein is that the fork-shaped anterior portion  200  of the body or spine  34  can also contribute to a self-opening or self-closing mechanism of the eyeglass  10 . In some embodiments, this feature can be provided in combination with the cam-assist closure mechanism. In this regard, the upper and lower fork members  240 ,  242  can be configured to resist compressive forces that would cause the upper and lower fork members  240 ,  242  to converge towards each other. In order to provide such compressive forces, the cam member  208  can interact with the upper and lower fork members  240 ,  242  to cause axial movement of the fork members  240 ,  242  as the body or spine  34  is rotated about an axis  262  defined by the joint  20 , and more specifically, the pin  204 . 
     For example, as illustrated in  FIGS. 16-17 , the cam member  208  can comprise one or more recesses  280  and one or more raised portions  282  formed along an upper surface  284  of the cam member  208 . In particular, some embodiments can comprise a plurality of recesses  280  that are spaced between a plurality of raised portions  282 . Nevertheless, it is contemplated that embodiments can be provided which include either a pair of protrusions and a recess or a pair of recesses and a protrusion. In this regard, the function of the recess and the protrusion is to urge a corresponding protrusion or recess formed on the anterior portion  200  of the body or spine  34  toward a given rotational rest position. 
     Thus, the number of recesses and protrusions formed in the cam member can determine the number of rotational rest positions. In use, the cam member  208  and the body or spine  34  can interact to create rotational rest positions. For example, if the body or spine  34  comprises a protrusion that engages the cam member  208 , the protrusion of the body or spine  34  will tend to be axially urged into a corresponding recess of the cam member  208 . Similarly, if the body or spine  34  comprises a recess that engages the cam member  208 , the recess of the body or spine  34  will tend to be axially urged to receive a corresponding protrusion of the cam member  208 . In either configuration, a rest position is achieved when the body or spine  34  is rotationally aligned with the cam member  208 . Thus, in some embodiments, a first rotational rest position can be achieved when the earstem is in a fully deployed position, and a second rotational rest position can be achieved when the earstem is in a stowed position in which the earstem is disposed adjacent to the frame of the eyeglass. 
     Continuing, the earstem  12  can be urged to one of the first and second rotational rest positions due to the spacing and mounting of the body or spine  34  and the cam member  208  between the upper and lower components  214 ,  216  of the recessed area  212  of the frame  16 . Specifically, during rotation, the earstem  12  is biased to one of the first and second rotational rest positions due to the propensity of the upper and lower fork members  240 ,  242  to resist a axial compression or deflection, along with the forced axial compression or deflection caused to the upper and lower fork members  240 ,  242  as the pin mounting component  252  as the protrusions  250  pass over the raised protrusions  282  of the cam member  208 . In this manner, the eyeglass  10  can provide an effective manner of maintaining the ear stands in one of the open and closed positions. 
     Optionally, it is contemplated that in some embodiments, the spring  206  can be used as an assist member to further urge the upper and lower fork members  240 ,  242  apart such that the earstem  12  is biased towards one of the first and second rotational rest positions. In this regard, the spring  206  could be configured to extend between the upper and lower fork members  240 ,  242 . In some embodiments, the spring  206  can make direct contact with the upper and lower fork members  240 ,  242 . Further, in some embodiments, the spring  206  can be disposed about the axis  262  of rotation of the earstem  12 . For example, the spring  206  can be passed over the elongate pin  204 . 
     Referring now to  FIGS. 20-22 , another embodiment of an eyeglass and earstem combination are shown.  FIG. 20  illustrates an eyeglass  1100  having a first earstem  1102 , a second earstem  1104 , and a frame  1106 . As shown in  FIG. 21 , the first earstem  1102  can comprise a plurality of segments  1110 ,  1112 ,  1114 ,  1116 . These segments  1110 ,  1112 ,  1114 ,  1116  can be monolithically formed along an elongate body  1120  or backbone of the first earstem  1102 . Accordingly, in such an embodiment, the segments  1110 ,  1112 ,  1114 ,  1116  and the frame  1106  can form a plurality of joints  1132 ,  1134 ,  1136 ,  1138  where at the first earstem  1102  can bend. 
     Similar to the embodiment discussed above with reference to  FIGS. 1-19 , the earstem  1102  can be uniquely configured to optimize the distance along the first earstem  1102  of the joints  1132 ,  1134 ,  1136 ,  1138 . Further, the spacing or gaps between the segments  1110 ,  1112 ,  1114 ,  1116  and the frame  1106  can also be optimized in order to limit and/or control bending of the first earstem  1102 . 
     Additionally, it is noted that the geometry of the first earstem  1102  at each of the joints  1132 ,  1134 ,  1136 ,  1138  can be selected such that variable or progressive bending occurs along the earstem  1102 . As illustrated, the joint  1132  can provide a wider cross-section, thus providing more limited movement and greater stiffness than the joint  1134  which provides a narrower cross-section. In this regard, the stiffness of the first earstem  1102  can be selectively controlled based on the dimensions and materials used for the joints, elongate body, and segments of the first earstem  1102 . 
       FIGS. 23-24  illustrate another embodiment of an eyeglass and earstem combination. As illustrated, an eyeglass  1200  can be provided that comprises a first earstem  1202  that is formed to include a plurality of segments  1210 ,  1212 ,  1214 ,  1216 . In this embodiment, the earstem  1202  comprises three flexible joints  1220 ,  1222 ,  1224 . The flexible joints  1220 ,  1222 ,  1224  can be disposed at approximately equal distances along the length of the earstem  1202 . Further, in such an embodiment, the segments  1210 ,  1212 ,  1214 ,  1216  can be formed monolithically with the earstem  1202 . As such, each joint  1220 ,  1222 ,  1224  can comprise a narrowed section of the earstem  1202  that is relatively more flexible than the segments  1210 ,  1212 ,  1214 ,  1216  thereof. Moreover, similar to the embodiments discussed above with reference to  FIGS. 1-22 , the earstem  1202  can be configured to progressively deflect, provide controlled deflection to a given deflected position, allow deflection within a given range, as well as the other features discussed above. 
     For example, as illustrated in the top views of  FIGS. 25 and 26 , the joint  1220  of the earstem  1202  can comprise a gap  240  that narrows until closing or bottoming out, thus limiting the deflection of the earstem  1202  at the joint  1220 .  FIG. 25  illustrates the joint  1220  prior to deflection, while  FIG. 26  illustrates the joint  1220  subsequent to deflection. 
     In accordance with an embodiment of another joint,  FIGS. 27-28  illustrate an earstem  1300  having a joint  1302  formed between adjacent segments  1304 ,  1306 . These segments  1304 ,  1306  are attached to an elongate body or backbone  1308 . As such, the joint  302  illustrated in  FIGS. 27 and 28  is similar to the embodiment illustrated in  FIGS. 10A-B . Accordingly, as the earstem  1300  deflects, the segments  1304 ,  1306  can contact each other to limit and/or control deflection of the earstem  1300 . As in  FIGS. 25-26 , a gap of  1310  formed between the segments  1304 ,  1306  can narrow until closing or bottoming out when the earstem  1300  moves from an undeflected position in  FIG. 27  to a deflected position in  FIG. 28 . 
     One of the unique aspects of the embodiment illustrated in  FIGS. 27-28  is the lateral overlap of the segments  1304 ,  1306  adjacent to the gap  1310 . In this regard, an end  1320  of the segment  1304  can be positioned adjacent to an end  1322  of the segment  1306 . When the earstem  1300  is deflected as shown in  FIG. 28 , the ends  1320 ,  1322  can form an interlocking joint that provides rigidity and stability for the joint  1302 . In such embodiments, the ends  1320 ,  1322  can comprise complementary interlocking features that engage each other during deflection of the earstem  1300 . 
     In accordance with yet another embodiment,  FIGS. 29-30  illustrate an eyeglass  1400  having an earstem  1402  that is coupled to a frame  1404 . As discussed above, the earstem  1402  can comprise many of the features and advantages provided and disguised with regard to the embodiments shown in  FIGS. 1-28 . However, the embodiment illustrated in  FIGS. 29-30  is unique in that the earstem  1402  comprises a plurality of segments  1410 ,  1412 ,  1414  that are comolded within the earstem  1402 . The segments  1410 ,  1412 ,  1414  can comprise a material that is different from the molded material forming the remainder of the earstem  1402 . As such, the earstem  1402  can comprise a plurality of joints  1420 ,  1422 ,  1424  at which the earstem  1402  has a reduced stiffness relative to areas of the earstem along which the segments  1410 ,  1412 ,  1414  extend. Similar to the embodiments discussed above, the cross-sectional dimension of the earstem  1402  can be selected so as to provide a desired degree of stiffness at each of the respective joints. 
       FIGS. 31 and 32  illustrate yet another embodiment of an eyeglass and earstem combination. As illustrated, and eyeglass  1500  can comprise an earstem  1502  that is coupled to a frame  1504 . The earstem  1502  provides a various similar features and functional attributes as the embodiments discussed and illustrated with reference to  FIGS. 1-30 . In the embodiment of  FIGS. 31 and 32  however, the earstem  502  comprises a plurality of segments  1510 ,  1512 ,  1514 ,  1516  that are interconnected in an end-to-end manner using discrete interconnector components or bodies  1520 ,  1522 ,  1524 . 
     In accordance with some embodiments, the interconnector bodies of  1520 ,  1522 ,  1524  can comprise springs or other resilience elements that allow motion between the segments  1510 ,  1512 ,  1514 ,  1516 . Similar to the embodiments discussed herein, the interconnector bodies  1520 ,  1522 ,  1524  can form joints of the earstem  1502 . In this regard, the individual interconnector bodies  1520 ,  1522 ,  1524  can each have different stiffnesses such that the joints between the segments  1510 ,  1512 ,  1514 ,  1516  provide progressive deflection. Further, as also noted above with respect to the other embodiments disclosed herein, each of the segments  1510 ,  1512 ,  1514 ,  1516  can provide a secondary degree of deflection in addition to the initial or primary degree of deflection of the interconnector bodies  1520 ,  1522 ,  1524 . 
     Furthermore, in accordance with any of the embodiments disclosed or showed herein, it is contemplated that the design of a given flex zone or point should also consider the yield stress of the component or ear stem. In this regard, it would be undesirable to exert a bending stress on the ear stem or one of its components which exceeds the yield stress of the ear stem or component. In such situations, deflection or de-formation of the ear stem or component would become inelastic. 
     Nevertheless, it is contemplated that certain portions of the earstem, such as the elongate body or spine can be formed of a material that is bendable to a given shape while retaining elastic properties. In this regard, it is contemplated that the posterior half or posterior portion of the elongate body or spine can be bended by the wearer in order to further customize the fit of the eyeglass. 
     Although these inventions have been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present inventions extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the inventions and obvious modifications and equivalents thereof. In addition, while several variations of the inventions have been shown and described in detail, other modifications, which are within the scope of these inventions, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combination or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the inventions. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed inventions. Thus, it is intended that the scope of at least some of the present inventions herein disclosed should not be limited by the particular disclosed embodiments described above.