Abstract: A frame seat unit of an eyegear includes a pair of frame seats and a bridge interconnecting the frame seats. Each of the frame seats defines an accommodation space that opens downwardly and has a frame strip that defines a top side of the accommodation space. The eyegear further includes a pair of lens units, each removably retained in the accommodation space of a respective one of the frame seats and including a lens frame and a lens. The lens frame has a ring portion for holding the lens therein. For each pair of the frame seat and the respective one of the lens units, one of the frame strip and the lens frame includes a releasably lockable tab, and an other one of the frame strip and the lens frame is formed with an engaging slot for engagement with the releasably lockable tab.

Abstract: The eyeglass structure mainly contains a frame and a viewing lens. At each interface between a front opening and the two temple members of the frame, a positioning slot with a protruding block therewithin is provided. On the other hand, two positioning pieces, each with a notch, are extended from the two ends of the viewing lens. To install the viewing lens, the positioning pieces are threaded into the positioning slots and the protruding blocks are embedded into the notches to secure the viewing lens. To detach the viewing lens, the positioning pieces are pulled to break out the locking of the protruding blocks and pushed to escape the confinement of positioning slots. The installation and detachment are therefore could be easily and conveniently conducted.

Abstract: A rigid lens retaining apparatus is permanently engaged with a substantially flexible eyewear frame during a formation molding process of the frame to provide a secure and releasable attachment of lenses to the substantially flexible eyewear frame through the rigid lens retaining apparatus.

Abstract: In a goggle lens interchange system, a goggle frame has a ledge on which a lens is removably placed, wherein the ledge is able to be exposed so that a lens of the goggles is able to be removed from the ledge, and another or replacement lens is able to be placed on the ledge.

Abstract: A rigid lens retaining apparatus is permanently engaged with a substantially flexible eyewear frame during a formation molding process of the frame to provide a secure and releasable attachment of lenses to the substantially flexible eyewear frame through the rigid lens retaining apparatus.

Abstract: Glasses such as bifocals, which have refractive lenses which are rotatable at least between two positions. A manual control rotates the lenses such that if bifocal, the relatively small, high magnification zone of each lens can be moved to a high position opposed to the usual low position of fixed bifocals. The user is spared the necessity of holding the head at an awkward posture when viewing overhead objects.

Abstract: The present invention provides protective eyewear, also referred to as sport goggles, where the lens and the flexible frame are easily separated and interchangeable. The lens and the flexible frame are both available in a variety of colors. Therefore, the wearer can select and easily assemble a preferred color combination. More specifically, the protective eyewear includes a lens received within a flexible frame and a strap that is permanently attached to the lens for securing the eyewear to a wearer's face. There are at least two connection apertures spaced around an outer perimeter of the lens. The flexible frame has at least two connection protrusions that are aligned with the connection apertures in the lens for removably receiving the connection apertures.

Abstract: This invention is related to an eyeglass nose-pad, an eyeglass assembly and fabricating methods of the same, the eyeglass assembly comprises a glass frame, a lens and a pair of nose-pads. The glass frame has a frame member including a groove for receiving the lens. A nose bridge extends outward from a center of the glass frame and has a pair of forks. The lens is received in the groove of the frame member and has protruding columns toward the forks so that accommodating spaces are defined between the protruding columns and the nose bridge. The lens may be an integral lens or a pair of separate lenses. The nose-pads made of a resilient material are received in the accommodating spaces. The nose-pad has an opening facing the fork of the nose bridge for receiving the fork and apertures facing the lens for being combined with the protruding columns of the lens.

Abstract: Eyeglasses having interchangeable frames comprise an eyeglass frame mounted with at least one lens frame. The eyeglass frame is formed with at least one receiving cavity having at least one first insertion slot near a nose pad portion of the eyeglass frame, at least one through hole having a same shape as a mating lens, and at least one second insertion slot adjacent to an outward end of the through hole. When the lens frame mounted with the lens is pressed into the receiving cavity, at least one first engaging portion and at least one second engaging portion extending from the lens frame are engaged with the first and second insertion slots, respectively. Thus, the eyeglass frame is stably combined with the lens frame through a simple and rapid assembling process, allowing eyeglass manufacturers to match such eyeglass frames and lens frames of different colors as needed.

Abstract: An eyeglass is provided for minimizing eyeglass weight without reducing the overall structural integrity of the eyeglass, and for allowing adjustability of the eyeglass to optimize optical and protective qualities during activities having differing head angles and primary lines of sight. The eyeglass can comprise a lens, a frame, and a nosepiece. The frame can have opposing terminals, an upper groove extending at least partially along the frame, and a post. The nosepiece can have a mounting component configured to engage the post such that the lens can be cooperatively retained between the frame and the nosepiece. The post can comprise one of a recess and a male connector, and the mounting component can comprise the other one of the recess and the male connector.

Abstract: Eyeglasses include a frame: a pair of lenses mounted detachably on the frame; and a pair of temples, each of which is pivoted to the frame so as to be rotatable relative to the frame between folded and extended positions, and each of which is provided with an abutting part that abuts against a respective one of the lenses when the respective one of the temples is disposed at the extended position, and that is spaced apart from the respective one of the lenses when the respective one of the temples is disposed at the folded position.

Abstract: Eyewear of the present invention includes a frame, at least one lens and a lens retaining member of non-metal material permanently engaging at least one lens. The lens retaining member extends along and projects radially and outwardly from at least a section of a periphery of the at least one lens. The lens retaining member is removably engaged with the frame.

Abstract: An eyewear system includes a partially entrapped eyewear frame, a lens, and a latching mechanism. The lens is configured to be received into a lens groove of the partially entrapped eyewear frame. The lens includes a first edge with a latch catch and a second edge with a tab configured to be received by a recess of the partially entrapped eyewear frame. The latch mechanism is configured to allow removal of the lens from the partially entrapped eyewear frame and engage the latch catch of the lens to retain the lens in the partially entrapped eyewear frame.

Abstract: This is a configurable eyewear system that has at least one temple member, at least one lens, a pair of mating members, and a connector. The at least one temple member and the at least one lens are rotatably connected by coupling at least one first mating member and at least one second mating member with the connector. The invention also has at least one containment structure and at least one lens that is rotatable within the containment structure. The invention further includes an eyewear lens that has a rotator and an eyewear lens that has an anchor cut-out. In addition, the invention includes an eyewear lens, that has at least a first prescription, an interior side and an exterior side on flip sides of the lens, wherein the viewing effect of the first prescription exists from the interior side and from the exterior side.

Abstract: A pair of glasses includes a frame and a wearing portion. The frame includes a groove in an end thereof. The groove includes an end opening facing a rear of the frame. The groove further includes a side opening in a lateral face of the end of the frame. The wearing portion includes an engaging member having a resilient tenon. The engaging member is removably engaged with the groove of the frame via the end opening, and the resilient tenon is engaged with the side opening. The resilient tenon of the engaging member is pressable into the groove of the frame to disengage from the side opening, allowing removal of the engaging member from the groove.

Abstract: A pair of glasses includes two lenses received in two lens receiving portions of a frame. A groove is defined in the frame and between tops of the lens receiving portions. Each lens receiving portion includes outer and rear stops for retaining the lenses. A movable stop includes two legs movably coupled with lower ends of inner sides of the lens receiving portions. The movable stop is movable between an engaged position in which a top portion of the movable stop is engaged with the groove and in which forward inclination of the lenses are stopped by the legs and a disengaged position in which the top portion of the movable stop is disengaged from the groove of the frame and in which insertion or removal of the lenses into or from the lens receiving portions is allowed.

Abstract: The goggles of the invention utilize a substantially rigid frame with separate top and bottom individually rotatable elements, namely an upper browbar and a lower nosepiece, that firmly capture the lens from above and below. The lens is further secured to the frame by projections on each of the browbar and nosepiece which fit through apertures in the lens. At the top, a post which projects forwardly from the frame is received in the well of the browbar by snap-fit engagement. At the bottom, a prong on the rotatable nosepiece passes through a bottom aperture of the lens and is received in a recess of a bottom portion of the frame by snap-fit engagement. The apertures and cooperating projections are preferably located along the center of a one-piece lens. Thus, the rotatable browbar and nosepiece capture the lens top and bottom by edgewise compression and hold the lens front-to-back.

Abstract: An assembly of a glasses frame and two legs provides a tool-free, self-assembly and most secured frame-leg attachment contributed by a three-dimensional frame-leg contact structure, which is created by a mortise-tenon contact plane, as well as a protruding piece embedded therein. The mortise-tenon contact plane is formed by a frame tenon extending from the side of a frame, and flexibly received in a corresponding leg mortise on the upper end of the leg. The frame tenon is further refined into two planes of different sizes to enhance the stability of frame-leg attachment.

Abstract: The present invention provides a structural arrangement and a method for attaching lenses to a frame of eyewear. The frame includes a major portion of substantially rigid material and a secondary portion of a softer material. A retainer is formed integrally with the secondary portion of the frame during formation of the secondary portion in a molding process in the presence of the lens such that the retainer contacts the lens to secure the lens in attachment with the frame body of the eyewear.

Abstract: Eyewear having a curved frame includes a protruding cover lens unit. The cover lens unit can be removably attached to the curved frame to position a less curved non-prescription lens in a protruding position with respect to the curved frame, thereby creating a space within the protruding lens unit. A prescription lens is removably attached to the curved frame and disposed behind the non-prescription lens. The prescription lens extends into the space without interference with the non-prescription lens.

Abstract: A fixing structure for lenses and a frame of eyeglasses is provided. A combining element integrally formed on a top of said styled lenses is concavely provided with a containing groove facing inwardly at a segment corresponding to styled lenses. Two sides of the containing grooves are provided with a wider distance at the outer end and narrow in toward the inner end. A hole is provided at a center and two sides on an upper flange of the combining element, respectively, so as to contain the strip on the two sides of the frame formed wider on the outer end and narrower on the inner end. The strip of the frame with the middle portion extended into a nose pad portion is provided with a protrusion corresponding to the hole opened on the combining element on top of the lenses, such that the two may be engaged together when assembled. A concave portion is provided at a bottom of a leg connecting element on the two sides of the frame, so as to support the two ends of the lenses when assembled.

Abstract: An eyeglass is provided for component weight without reducing the overall structural integrity of the eyeglass, and for allowing adjustability of the eyeglass to optimize optical and protective qualities during activities having differing head angles and primary lines of sight. The eyeglass can comprise a lens, a frame, and a nosepiece. The frame can have opposing terminals and an upper groove extending at least partially along the frame and a downwardly extending post. The nosepiece can have a mounting component extending upwardly to engage the post, and the lens can be cooperatively retained between the frame and the nosepiece. Sets of corresponding nose pieces and lenses are provided, to optimize the eyeglasses for different primary viewing axes in the vertical plane.

Abstract: The clip-lens eyeglasses frame includes a face structure provided with elements for clipping to at least one lens and arranged to operate by resiliently clamping the lens in a direction that is generally axial relative to the lens.

Abstract: Eyewear of the present invention includes a frame of substantially rigid material, at least one lens and a substantially rigid lens retaining member permanently engaging at least one lens. The lens retaining member extends along and projects radially and outwardly from at least a section of a periphery of the at least one lens. The outer edge of the lens retaining member is removably engaged with the frame.

Abstract: An integral and biased lens interchange system configured to be used with various types of eyewear. The eyewear includes at least one lens and a frame having a rim supporting the at least one lens. The interchange system includes a biasing member incorporated in at least one of a bridge of the frame and the rim of the frame.

Abstract: Rimless eyewear features a wire that encircles a lens. Systems are provided for selectively increasing or decreasing a tensile load on the wire to facilitate assembly and maintenance of the eyewear. An adjusting screw, different wire securement positions, and/or adjustment shims provide easy tension adjustment of the wire and secure the eye lens in a predetermined position and orientation.

Abstract: Convertible eyewear permits ready conversion between various optical modes. A removable shield is removable secured by magnetic force to a frame by the interaction of at least one magnetic rivet recessed within the frame and at least one magnetic rivet that protrudes from the shield. The mating magnetic rivets may have contacting surfaces of oval shape with the rivet recessed within an oval-shaped channel to prevent misalignment of frame and shield with a single point of magnetic contact. A prescription lens insert and a goggle adapter, each having a protruding magnetic rivet, are compatible for magnetic fixation to the frame of the eyewear.

Abstract: A pair of eyeglasses includes two temple pivotal bases respectively connected to the opposite sides of a lens frame, and each temple pivotal base has its front side formed with a recessed surface. Two cover-position members are respectively and pivotally assembled on the recessed surface of the temple pivotal base. The lens frame has the opposite portions near a bridge respectively provided with an arc-shaped recessed groove for fitting a lens therein. To assemble a lens on the lens frame, simply turn open the cover-position member, fit the lens in the recessed groove through the recessed surface and then close pivotally the over-position member on the recessed surface to finish assembly of the lenses.

Abstract: A pair of eyeglasses with lens fastening arrangement includes a frame having two sets of one or more through holes formed on an outer top and/or bottom edge of each of a pair of openings. The through holes communicate with grooves of the openings. A pair of lenses each includes one or more projections formed on an outer top and/or a bottom edge of each lens. The projection is adapted to lockingly engage with the through hole with peripheral edges of the lenses being inserted into the grooves of the openings of the frame when the lenses are firmly fitted in the openings of the frame. Thereby, loosening of the lenses by bending temples of the eyeglasses is substantially impossible.

Abstract: A lens combined with a soft eyeglasses rim includes a lens and a soft eyeglasses rim. The lens is provided with plural holes spaced apart near a circumference in advance, and then placed in a mold for making the soft eyeglasses. Then the soft eyeglasses rim is injected molded in the mold with the finished lens previously placed. Thus the soft eyeglasses rim is formed with plural projections corresponding to and fitting in the plural holes of the lens as fused to keep the rim with the lens in a stable and secured condition.

Abstract: An eyeglass comprises a eyeglass frame having a nose bridge frame at a middle portion of the eyeglass frame; an inner side of the nose bridge frame having two U shape embedding grooves; an inner side of each embedding groove being an attaching surface; a lower side of the nose bridge frame being formed with a nose pad; a front surface of the nose pad being formed as a resisting surface; a front surface of the eyeglass frame at two sides of the nose bridge frame being formed as an adhering surface; two eyeglass legs being connected to the eyeglass frame; and a lens assembled to the eyeglass frame; a middle section of the lens being a nose bridge portion; and two upper sides of the nose bridge portion being formed with respective adhering portions which can be adhered to the adhering surface of the eyeglass frame.

Abstract: A pair of spectacles has a frame and two lenses. The frame has a skeleton and a bridge formed between the skeleton and dividing the skeleton into two symmetrical members. Two first lugs are transversely formed in a distal end of the skull and adjacent to the bridge, and two second lugs are uprightly formed in a free end of the skull and opposed to the bridge. Two lenses are respectively mounted on the members and respectively have a first channel and a second channel defined in a periphery of the lenses. Two first tabs and two second tabs are respectively mounted on the lenses and the frame in turn, whereby the lenses are securely provided on the frame with easy assembly.

Abstract: Eyeglasses have a lens member, a frame member and two temples. The lens member includes opposite front and rear lens surfaces, two through holes at left and right ends of the lens member, and an insert hole disposed between the through holes. The frame member includes a middle frame portion abutting against the front lens surface of the lens member, two retaining frame portions formed respectively on left and right ends of the middle frame portion and extending respectively through the through holes in the lens member, and an insert bar extending rearwardly from the middle frame portion and inserted into the insert hole in the lens member. The retaining frame portions abut against the rear lens surface of the lens member. The temples extend respectively and rearwardly from the retaining frame portions of the frame member.

Abstract: Eyewear having an interchangeable single lens, that can be replaced quickly and easily, is provided. The eyewear is particularly suitable for use as safety eyeglasses. The eyewear includes a unitary frame structure having an inner and outer surface. The frame includes a brow bar portion extending laterally across the brow of the wearer, a nose bridge portion depending downwardly from the brow bar, first and second outer temple portions at the outer ends of the brow bar, and lower lens frame portions. The structural frame portions are preferably molded from a relatively rigid plastic material. To provide for attachment of the lens to the frame, the first and second outer temple portions each include a molded elastomeric inset including a post-receiving aperture for receiving a complementary mounting post formed on the lens. Additionally, the nose bridge portion or the center of the brow bar may also include a locking mechanism for holding the lens in position in the central area.

Abstract: An eyewear device includes a frame having two elongate extensions rotatably attached to the frame and movable between a deployed position and a stored position. The frame has two lens receiving portions with multiple lens units insertable in the lens receiving portion some through the front surface and some through the rear surface. The lens units have different eye glass lenses held therein. The elongate extensions include at least one head grip that is movable between two positions in which the head grip extends away from the stem, extensions, ears or temples different distances. A retainer is provided to hold the eyewear to the head; and a leash is provided to secure the eyewear to the clothing. The lens receiving portions have ridges that are configured to interact with grooves in the lens units to hold them in the frame. including a peripheral encasing. The lens units may have a nose piece with a nose pad configured to be removable and to adjust the distance of the nose pad from a support surface.

Abstract: A method for assembly of an eyewear and an eyewear structure are provided to incorporate preferred properties into the eyewear. A lens is encircled by a rim element having the preferred properties thereby forming a lens unit which is removably attached to the eyewear structure. Therefore, the lens can be better retained within the eyewear structure. Such lens units can be made interchangeable one to another, and with a variety of individual properties such that replacement of the lens unit attached to the eyewear structure with a selected one of the interchangeable lens units, will change the properties of the eyewear as per user's preferences.

Abstract: Safety eyewear (10) having interchangeable lens(es) (28,30) is provided. To provide for interchange of the lenses (28,30) in the frame (12), upper and lower frame members (32,34) are molded from a harder, more rigid plastic while lateral temple portions (20,22), and a central nose bridge portion (18) are molded from a softer, more elastic material. The entire frame structure (12) is preferably molded as a unitary piece to form a unitary frame having rigid upper and lower frame portions (32,34) joined by flexible intermediate portions (18,20,22). In this regard, the upper and lower frame portions (32,34) can be flexed or stretched relative to each other to temporarily separate the frame portions (32,34) and open up the lens openings (24,26).

Abstract: A pair of self-assembly glasses includes a frame, a fixing member and a lens suit. The frame includes a body and a pair of arms pivotably connected to opposite sides of the body. The body is made through integral molding. A number of positioning holes are defined in the body. The fixing member is made through integral forming. The fixing member includes a pair of fixing portions with a plurality of positioning holes defined therein respectively. A number of positioning holes are defined in the lens suite corresponding to the positioning holes of the body. Thus, it is ready to assemble or disassemble the self-assembly glasses through the positioning holes of the lens suite, the fixing member and the frame.

Abstract: The present invention relates to a pair of eyeglasses comprising a pair of temples; a frame comprising two forward peripheral grooves either including two spaced first tabs at a nosepad portion of the frame, and a second tab at an endpiece portion of the frame; and a pair of lenses either comprising two spaced first apertures at its inner side and a second aperture at its outer side. The first apertures are adapted to lockingly engage with the first tabs and the second apertures are adapted to lockingly engage with the second tabs respectively in response to snapping the lenses onto the grooves. The assembly or disassembly of the lenses is fast and easy.

Abstract: Eyewear is provided with an exchangeable lens retaining member which is removably attached to a lens to form a lens unit. The lens unit is detachably secured to the main frame of the eyewear such that the lens unit extends downwardly from the main frame. At least a section of the lens retaining member provides a spacing between a bottom of the main frame and the lens, where vent passages are defined.

Abstract: A pair of easy-to-assembly eyeglasses includes a primary frame and a secondary frame. The primary frame includes a horizontal rod. A nose padding member extends downward from a central portion of the horizontal rod and includes two legs each defining an engaging groove. Two temples are respectively pivoted to two sides of the primary frame. The horizontal rod includes an extension extending forward and downward from an intermediate portion thereof, delimiting a downwardly facing engaging space. The secondary frame includes two rings, two lenses respectively received in the rings, and a bridge between the lenses. The bridge includes two protrusions respectively engaged with the engaging grooves of the nose padding member. The secondary frame further includes an engaging plate engaged in the downwardly facing engaging space. The secondary frame can be rapidly replaced with a desired one to match the primary frame or to provide a reading function.

Abstract: Eyewear includes a half-jacket frame. A removable shield, extending from the half-jacket frame to the wearer's face, may be provided to prevent direct impingement of air and dust on the wearer's eyes. The half-jacket frame includes a left indent, a left upper lens groove adapted to receive a left lens, a right indent, and a right upper lens groove adapted to receive a right lens. The removable shield includes a left lens opening, a left detent adapted to cooperatively receive the left indent of the half-jacket frame, a left lower lens groove adapted to receive the left lens and mate circumferentially with the half-jacket frame, a right lens opening, a right detent adapted to cooperatively receive the right indent of the half-jacket frame, and a right lower lens groove, adapted to receive the right lens and mate circumferentially with the half-jacket frame. The half-jacket frame may be constructed of titanium.

Abstract: The present invention provides eye protection systems. The eye protection systems include a lens capable of being mounted in and being interchangeable between a plurality of different lens-mounting platforms. These platforms may include spectacles or goggles with release mechanisms, which permit the lens to be removed while providing full ballistic protection when installed in the platform. The lens of the present invention protects against a plurality of threats including spectrums of light, such as sun light, ultraviolet light, or laser light, wind, dust, projectiles, etc. The lens may include a laminate structure, which protects sensitive technologies from exposure to environmental conditions, such as chemicals, weather, etc.

Abstract: The present invention provides a method and structural arrangement for permanently attaching lenses to a pair of eye glasses which include a frame structure made of substantially rigid plastic material. The attachment of the lenses to the frame structures of eye glasses is achieved during the formation of the frame structures. A variety of engaging structures between the lenses and a frame body can be formed together with the formation of frame structure in a plastic formation molding procedure.

Abstract: The present invention discloses a soft pad structure of glasses having a soft pad. The soft pad includes a fixing member of long shape to wrap the edge of an upper portion of the eyeglass. The fixing member forwarding the inner and outer sides of the eyeglass extends down to form a lining pad and a decorative member to cover the inner and outer surfaces of the eyeglass. The eyeglass and the fixing member of the soft pad are embedded in an embedding trench of the frame body to be form-integrated. The lining pad can be a leaning pad for providing comfortable wearing experiences for users and the decorative member can be coating in different colors to enhance the appearance while wearing. In addition, the soft pad of the present invention can be assembled rapidly and firmly with out any manual tools to improve the purpose of convenient combination and easy repair.

Abstract: A pair of improved eyeglasses is disclosed. The eyeglasses comprises a first frame including a left opening and a right opening, a detachable second frame including two lenses aligned with the openings, a projected rim, a groove surrounded by the rim with the first frame being fitted therein by snapping, and two pairs of an upper tab and a lower tab forward the groove by a predetermined distance for fastening the first frame at the groove, and two temples pivotably coupled to ends of the first frame.

Abstract: An eyeglass assembly comprises a lens and a frame member. One of the lens and the frame member has a recess formed in it which has a generally constant cross-section when viewed from one end along at least part of its length. The recess is defined by a pair of opposed arms with reentrant portions at their ends which define a longitudinal opening between them extending along at least part of the length of the recess, and it has an opening at one end. The other of the lens and the frame member bears a head portion. The recess and the head portion are configured so that the head portion can be fitted into the recess by sliding it through the opening at the said end of the recess, and so that the head portion is prevented by the reentrant portions of the arms from being withdrawn from the recess through the longitudinal opening.

Abstract: The protective eyewear assembly described comprises a frame having right and left portions defining respective right and left apertures and a central bridging portion, and a protective lens piece adapted to be mounted to the lens piece between the upper and lower edges of the frame. The lower edge of the frame has a retaining wall for retaining the lens therein while the upper edges of the frame and the lens piece have cooperating portions to secure the lens to the frame. The frame may be made of flexible plastic material to enable a snap-in engagement and a snap-out disengagement of the lens to and from the frame.

Abstract: An eyeglasses includes a lens part, and a frame having a front; the lens part has rearwards extending wings at two ends, and an engaging hole on a middle; each wing has a slot having rear and front sections; the front has a post fitting with the engaging hole, and insertion portions fitting with the slot rear sections on inward sides of two folded ends; stopping portions are formed on the insertion portions, and are shaped such as to be passable through the slot front sections; the stopping portions are longer than the slot rear sections such that the lens can be firmly coupled to the front by means of displacing the lens part rewards relative to the front to insert the post in the engaging hole and fit the insertion portions in respective slot rear sections after the stopping portions have been passed through respective slot front sections.

Abstract: A pair of eyeglasses includes two frames each having a cutout defined in an outer periphery of the frame, two temples each pivotally connected to a corresponding one of the two frames and by a boss sandwiched between each of the temple and the corresponding frame, a bridge securely bridging the two frames together by an extension sandwiched between the bridge and a corresponding one of the two frames, two lenses each connected to a corresponding one of the two frames and having two notches oppositely defined in a side of the lens to respectively correspond to the extension and the boss and an indentation defined adjacent to one of the two notches to align with the cutout of the frame, and a positioning arm pivotally connected to the two frames to selectively combine the frames and the lenses.