Patent Publication Number: US-8992060-B2

Title: Uniform illumination of lamps

Description:
BACKGROUND 
     Vehicle manufacturers have been investigating the implementation of light emitting diodes (LEDs) in lamp assemblies in view of the multiple benefits associated with LEDs. For instance, LEDs may require substantially less power than incandescent bulbs, so as to decrease strain on a vehicle battery and increase available electricity for other vehicle systems. Examples of these systems may include DVD players, sound systems and other demanding systems. In addition, LEDs do not have filaments and may therefore be more durable than the counterpart incandescent bulbs. LEDs may also have a lifespan of up to a typical life of a vehicle, which may be significantly longer than that of incandescent bulbs. Moreover, LEDs may generate less heat than incandescent bulbs, thus increasing the longevity of nearby electronic components and plastic components. Furthermore, LEDs may have a greater range than that of incandescent bulbs by, for example, an order of two or three. 
     It would therefore be desirable to provide a vehicle lamp assembly producing uniform illumination, requiring less maintenance and consuming less energy. 
     SUMMARY 
     One embodiment of a vehicle lamp assembly may include a housing, which includes a pair of opposing reflective surfaces defining a chamber therebetween. The assembly may further have a single light emitting diode (LED) disposed within the chamber and a lens carried by the housing. One or more of the reflective surfaces may have a grain pattern configured to interact the light emitted from the single LED with the housing in a range between one and five times before the housing directs the light through the lens. 
     Another embodiment of a vehicle lamp assembly may have a housing, which includes a pair of reflective surfaces defining a chamber therebetween. The assembly may also have a single LED disposed within the chamber and a lens carried by the housing. In addition, the assembly may have an opaque member, which may be disposed within the chamber and block light directed from the single LED to at least a portion of the lens that is adjacent to the single LED. At least one of the reflective surfaces may have a grain pattern configured to interact light with the housing in a range between one and five times before the housing directs the light through the lens. 
     Still another embodiment of a vehicle lamp assembly may include a housing, which has a pair of opposing reflective surfaces defining a chamber therebetween. The assembly may further include a single LED disposed within the chamber and a lens carried by the housing. At least one of the reflective surfaces may have a grain pattern configured to interact the light emitted from the single LED with the housing in a range between one and five times before the housing directs the light through the lens. The single LED may have a predetermined angle of throw that directs light toward the reflective surfaces to facilitate the light in interacting with the housing in the range between one and five times before the housing directs the light through the lens. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view of one embodiment of a vehicle lamp assembly. 
         FIG. 2  illustrates a cross-sectional view of the lamp assembly of  FIG. 1 , as taken along line  2 - 2 . 
         FIG. 3  illustrates a cross-sectional view of the lamp assembly of  FIG. 1 , as taken along line  3 - 3 . 
         FIG. 4  illustrates a perspective view of a portion of the vehicle lamp assembly of  FIG. 1 , with a bezel removed from the assembly. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the discussion that follows and also to the drawings, illustrative approaches are shown in detail. Although the drawings represent some possible approaches, the drawings are not necessarily to scale and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the present disclosure. Further, the descriptions set forth herein are not intended to be exhaustive or otherwise limit or restrict the claims to the precise forms and configurations shown in the drawings and disclosed in the following detailed description. 
     An exemplary a vehicle lamp assembly may include a housing and a single light emitting diode (LED) disposed within a chamber defined between two opposing reflective surfaces of the housing. One or more of the reflective surfaces may have a grain pattern configured to redirect or interact the light emitted from the single LED with the housing in a range between one and five times before the housing directs the light through a lens carried by the housing. In this respect, the amount of light or energy lost through interactions with the housing can be reduced, so as to permit illumination of at least a portion of the assembly by only one LED. By way of two examples, five interactions with a housing having 95% reflecting surfaces may lose only 27% of the energy, and five interactions with a housing having 90% reflecting surfaces may lose 40% of the energy. Of course, however, a portion of the light may interact with the housing more than five times before exiting the assembly. 
     Referring to  FIGS. 1 through 4 , one embodiment of a vehicle lamp assembly  100  may include a housing  112 , which defines a chamber  122  through which light is uniformly scattered. In particular, the housing may include a bezel  114  and a back plate  116  attached to the bezel by screw fasteners, welding, adhesive or any suitable fastener. As best shown in  FIGS. 2 and 3 , the housing may have a pair of opposing reflective surfaces  118 ,  120  defining the chamber  122  therebetween. For example, the bezel  114  may have the reflective surface  118 , and the back plate may have the reflective surface  120  facing and opposite to the reflective surface  118  of the bezel so as to define the chamber. As one example, the chamber may be somewhat flat and wide to the extent that a mean distance between the reflective surfaces may be less than a square root of the overlapping surface areas of the reflective surfaces. However, the chamber may have other suitable shapes as desired. 
     The assembly  100  may further include a lens  124  carried by the housing. For example, the bezel  114  may have an outer perimeter  126  with an opening  128 , which may extend along the perimeter and include a seat  130  or flange that receives the lens. However, the bezel may have other suitable portions carrying the lens. Furthermore, the bezel may have a central portion  132  disposed radially inward with respect to the perimeter and a central axis  134  extending laterally across the bezel through the central portion. 
     As best shown in  FIG. 2 , the assembly  100  may also include a single light emitting diode  136  (“LED”) disposed within the chamber and on a central axis  134  extending laterally across the housing. The single LED  136  may have a predetermined angle of throw that directs light toward the reflective surfaces to facilitate the light in interacting with the housing in a range between one and five times before the housing directs the light through the lens. This may reduce the amount of light lost through interactions with the housing so as to permit the use of only one LED to illuminate the assembly. Limiting the number of LEDs to one per chamber may decrease the cost of each assembly, reduce power requirements of the assembly and increase the lifespan of adjacent components. The LED may be disposed within the chamber and spaced apart from the lens, such that the housing blocks a direct external line of sight through the lens to the LED. In this respect, the portions of the assembly, which are illuminated by the LED, may be uniformly illuminated. 
     The assembly may also have an opaque member  138 , such as a ramp, bracket or partition, which may be disposed within the chamber  122  and block light directed from the single LED  136  to at least a portion of the lens that is adjacent to the LED or spaced apart from the LED by a distance that is less than other portions of the lens. In this respect, the portions of the lens that is closest to the LED may be indirectly illuminated by the LED, such that those portions of the housing may not appear brighter than other portions of the housing, which are spaced a greater distance apart from the LED. 
     The reflective surfaces  118 ,  120  may be white for diffusely reflecting light throughout the chamber thereby facilitating the single LED with uniformly illuminating the housing. In addition, the reflective surfaces  118 ,  120  may have a grain pattern  140 ,  142  configured to interact the light emitted from the single LED with the housing in the range between one and five times before the housing directs the light through the lens. In this respect, the amount light lost during interactions with the housing may be reduced while permitting the light to be sufficiently scattered to uniformly illuminate the housing. In another embodiment, only one of reflective surfaces  118 ,  120  may have the grain pattern. In addition, the grain pattern may be configured to redirect the light through the chamber such that the light interacts with the housing more or less than five times. 
     The assembly may further include a supplemental LED  144  carried by an outer side  146  of the bezel opposite to the chamber  122 . In addition, the assembly  100  may also have a supplemental lens  124  carried by the bezel to define a supplemental chamber  122 , and a cover assembly  148  carried by the bezel. The cover assembly  148  may extend over the chamber, the lens, the supplemental chamber, the supplemental lens, and the bezel. 
     Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent upon reading the above description. The scope should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the technologies discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In sum, it should be understood that the application is capable of modification and variation. 
     All terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those knowledgeable in the technologies described herein unless an explicit indication to the contrary in made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. 
     The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.