Abstract:
A light assembly for an automotive vehicle includes a lens holder that supports an internal lens. The light assembly includes a light source powered by the vehicle. The internal lens includes an undulating surface facing the light source. A reflective metallic layer is disposed along the undulating surface to provide enhanced scattering of light and heat away from a reflex lens.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 11/151,607 filed on Jun. 13, 2005, the contents of which are incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to light assemblies for automotive vehicles. More particularly, the invention relates to a lens holder having an inner lens for diffusing heat emitted from a light source. 
     2. Description of the Related Art 
     Automotive vehicles include light assemblies for providing indicator signals visible to persons in other vehicles or as pedestrians. A light assembly typically includes a housing defining an enclosed space and a socket for supporting a light emitting source, such as an incandescent bulb, within the enclosed space. The housing also includes an outer lens that is colored according to its specific function, such as red for a stop signal and yellow or orange for turn signals. Packaging constraints, due to aesthetics or function, sometimes requires the design of a compact light assembly, resulting in a short distance between the light emitting source and the outer lens. But, the outer lens cannot be placed too close to the light emitting source due to heat that radiates therefrom. Thus, it remains desirable to provide a means of diffusing or blocking heat coming from the light emitting source to allow the design of a more compact housing for the light assembly. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, a lens assembly is provided for use with an automotive vehicle having a light source. The lens assembly includes a reflex lens, a lens holder, an internal lens and a metallic layer. The lens holder has an inner surface facing the light source. The holder has an outer surface opposite the inner surface. The lens holder is adapted for supporting the reflex lens along the outer surface. The internal lens is positioned between the light source and the reflex lens. The internal lens has an undulating surface facing the light source and defined by a plurality of annular bumps. The metallic layer is disposed along the undulating surface to provide enhanced scattering of light and heat energy away from the reflex lens to provide enhanced scattering of light and heat energy away from the reflex lens. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
         FIG. 1  is an exploded perspective view of a light assembly according to an embodiment of the invention; 
         FIG. 2  is a cross sectional view of the internal lens; 
         FIG. 3  is a cross sectional view of the internal lens according to a second embodiment; 
         FIG. 4  is a cross sectional view of the internal lens according to a third embodiment; 
         FIG. 5  is a cross sectional view of the light assembly according to a fourth embodiment of the invention; and 
         FIG. 6  is a cross sectional view of the light assembly according to a fifth embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An embodiment of the invention provides an optical light assembly for use on an automotive vehicle that includes a novel inner lens design that disperses heat and light energy emitted from a light source, which minimizes deformation of a plastic lens placed in proximity to the light source. 
     Referring to  FIG. 1 , an optical or lens assembly for use on an automotive vehicle is generally indicated at  10 . The lens assembly  10  includes a translucent lens holder  12  having a parabolically shaped wall  14 . The wall  14  has opposite inner  16  and outer  18  surfaces. An opening  19  is formed in a generally central region of the wall  14 . 
     The lens assembly  10  also includes an internal lens  20 . The internal lens  20  is integrally formed with the lens holder  12  and is made of acrylic, polycarbonate or other conventional materials known by those skilled in the art. Optionally, the internal lens  20  is formed separate from and subsequently fixedly secured to the lens holder  12  by conventional methods, such as sonic welding or adhesives. The internal lens  20  is positioned along the inner surface  16  of the wall  14  adjacent the opening  19 , so as to define a pocket or recess  21  along the outer surface  18 . 
     The internal lens  20  is generally disc shaped with opposite first  22  and second  24  surfaces facing in generally the same direction as the inner  16  and outer  18  surfaces of the wall  14 , respectively. The first surface  22  is defined by a plurality of outwardly extending light reflecting protrusions  26 . Preferably, the protrusions  26  are pillow or generally hemispherically shaped, as shown in  FIG. 2 . Optionally, in a second embodiment, the protrusions  126  have a rectilinear or cubic corner shape, as shown in  FIG. 3 . Optionally, in a third embodiment, the protrusions  226  are defined in the second surface  224  rather than the first surface  222 . 
     A reflex lens  30  is seated in the recess  21  in the wall  14 . The reflex lens  30  is generally parallel with the internal lens  20 . A space is defined between the reflex lens  30  and the internal lens  20 . A hole  28  is formed in the internal lens  20  to ventilate the space between the reflect lens  30  and the internal lens  20 . 
     The lens assembly  10  also includes a back wall  40  spaced apart from the lens holder  12 . The back wall  40  includes a conventional socket  42  for supporting a light source. The back wall  40  also includes a reflective surface  44  facing the lens holder  12 . An outer lens  50  is fixedly secured to the back wall  40 . 
     In use, light and heat are emitted from the light source  44 . Light from the light source  44  and also light reflected from the reflective surface  44  of the back wall  40  pass through the lens holder  12  and the outer lens  50 . Both light and heat from the light surface are diffused or scattered by the protrusions  26  so that the reflex lens  30  and the outer lens  50  remain below their respective heat deflection temperatures. Some of the light reflected by the protrusions  26  are directed toward the reflective surface  44 , and re-directed outwardly through the outer lens  50 . Thus, the internal lens  20  serves the dual purposes of minimizing the temperatures of the reflex  30  and outer lenses  50 , and increasing the overall brightness of the light observed coming from the lens assembly  10 . 
     Referring to  FIG. 5 , a fourth embodiment is shown, wherein like parts from other embodiments described herein are indicated by like numerals offset by 100, a metallic layer  60  is provided along the first surface  322  of the internal lens  320 . Preferably, the metallic layer  60  is aluminum. Optionally, the metallic layer  60  is provided on the second surface  324  of the internal lens  320 . In use, the metallic layer  60  enhances the tight and heat deflecting function of the internal lens  320 . The metallic layer  60  provides still further enhancement of the overall brightness of the light observed coming from the lens assembly  310 . 
     Referring to  FIG. 6 , a fifth embodiment is shown, wherein the internal lens  420  has a plurality of annular bumps  70 . The bumps  70  are concentric about a central raised bump or portion  72 . The bumps  70 , form a conical shape raised axially toward the lamp. The metallic layer  460  is provided along the first surface  422  of the internal lens  420 . The metallic layer  460  is aluminum, or other suitable light and heat reflecting material known to those having ordinary skill in the art. The metallic layer  460  follows the bumps along the cross section of the internal lens  420 , thereby providing enhanced light and heat scattering characteristics over the previous embodiment. 
     The invention has been described in an illustrative manner. It is, therefore, to be understood that the terminology used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Thus, within the scope of the appended claims, the invention may be practiced other than as specifically described.