Abstract:
The present invention relates to a lens for a light-emitting diode (LED) vehicle marker having a projection for increasing visibility of the vehicle to which the marker is affixed. In accordance with one embodiment of the present invention, the lens includes a generally elongated projection which increases longitudinal illumination.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a lens for use with markers for vehicles that have a light-emitting diode (LED) light source and, more particularly, to a lens having a projection for increasing visibility from the side of the vehicle to which the marker is affixed. 
   2. Description of Related Art 
   Vehicle markers, such as clearance markers, reflective devices and similar types of markers used on vehicles are typically mounted to the front, rear and sides of a vehicle, such as an automobile or truck/trailer combination, to indicate the overall height, width and length of the vehicle. For example, § 108 of the Federal Motor Vehicle Safety Standards and Regulations (“FMVSS”) requires all vehicles to have a certain number of vehicle markers, including clearance markers and reflective devices, mounted permanently to a part of the vehicle. According to the FMVSS, the Society of Automotive Engineers (“SAE”) is the organizational body directed to setting standards and recommended practices for compliance with the provisions of the FMVSS. The purpose of these standards and practices is to reduce traffic collisions and deaths and injuries resulting therefrom, by providing adequate illumination of both the roadway and the vehicle in daylight and in darkness (or other conditions of reduced visibility). 
   Vehicle markers are mounted on the vehicle to provide light to the front, rear and sides of a vehicle in order to indicate the overall width, height and length of the vehicle. For example, according to SAE standards, a red clearance marker is used to indicate the rear of the vehicle and an amber clearance marker is used to indicate the front of the vehicle. Furthermore, a “PC” rating is an indication that according to the SAE standards, the marker can be seen easily from both the side and the front. Therefore, to achieve a “PC” rating, the clearance marker must emit light in an arc-like pattern. 
   Vehicle markers include a housing, which includes the light source, and a lens, which protects the light source from the natural elements. Typically, the light source for such markers is either a standard high-intensity incandescent bulb, which has a relatively short life span and is susceptible to damage, or a light-emitting diode (LED), which has a greater operating life. 
   One of the problems associated with using an LED light source is the difficulty in spreading the illumination in a longitudinal direction, i.e., an arc-like pattern. While LEDs can have an operating life of up to 100,000 hours before degradation commences, the light emitted from LEDs is in a narrow cone-shaped pattern. More specifically, an LED is a directional light source in which the maximum emitted light is in a direction perpendicular to the light surface. A typical radiation pattern for an LED is within 20° of the direction of the maximum light, which is significantly less than the SAE standard for visibility for a side clearance marker. Accordingly, an LED light source is not ordinarily used for side clearance markers because of the inability of the LED clearance markers presently known in the art to spread the light in an arc-like pattern as required by SAE standards. 
   Thus, there exists a need to provide a lens suitable for use with an LED vehicle marker which is relatively inexpensive and easy to manufacture and which provides the requisite illumination pattern. 
   SUMMARY OF THE INVENTION 
   The present invention satisfies the foregoing and other needs. The present invention relates to a lens for use with a vehicle marker having an LED light source. In one embodiment, the lens of the present invention is used with a clearance marker and includes an elongated projection which permits longitudinal illumination. 
   In accordance with one embodiment of the present invention, the lens includes a lens periphery joined to the housing assembly of the clearance marker thereby creating a light source chamber, and a lens structure joined to the lens periphery. The lens structure has a front surface, which includes a projection for directing light emitting from an LED light source outwardly from the clearance marker in an arc-like pattern. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which: 
       FIG. 1  is a front perspective view illustrating a clearance marker incorporating a lens in accordance with one embodiment of the present invention; 
       FIG. 2  is a back perspective view illustrating a lens in accordance with one embodiment of the present invention; 
       FIG. 3  is a right-side plan view of a clearance marker incorporating a lens in accordance with one embodiment of the present invention; and 
       FIG. 4  is a top plan view of a clearance marker incorporating a lens in accordance with one embodiment of the present invention. 
       FIG. 5  is a front elevational view of a clearance marker incorporating a lens in accordance with one embodiment of the present invention. 
   

   DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   Certain exemplary embodiments of the present invention will now be described with reference to the drawings. In general, such embodiments relate to a lens containing a projection for directing light emitting from an LED light source outwardly from a vehicle marker in a substantially arc-like pattern, preferably so that light emitting from the plurality of LEDs can be viewed at an angle greater than 20° axial orientation of each LED. 
   Turning to  FIG. 1  (a front perspective view), according to a first embodiment of the present invention, a clearance marker  10 , which includes a housing  20  and a lens  30 , is particularly suited for use with an LED light source. Lens  30  comprises a projection or any other raised, translucent surface which can disperse light emitting from an LED light source in an outwardly, substantially arc-like pattern. 
   Considering a substantially rectangular-shaped clearance marker for illustration purposes only, and noting that any shape and/or size clearance marker, if used, can be (but need not be) identical in construction, lens  30  comprises a peripheral wall  40 , which supports opposing side walls  50  and  54  and mounting walls  60  and  62 . Opposing side walls  50  and  54  and mounting walls  60  and  62  support opposing end walls  70  and  72 , which support an arcuate projection wall  80 . Arcuate projection wall  80  includes an arcuate projection  90  which allows light from an LED light source (not depicted) to spread outwardly in a substantially arc-like pattern. 
   As shown in  FIG. 1 , projection  90  is a substantially elongated form and has a projection middle portion  93  and opposing projection side portions  92 . In a first embodiment of the present invention, the width of projection middle portion  93  is equally greater than the width of the opposing projection side portions  92 . 
   Opposing side walls  50  and  54 , each having an inner surface,  51  and  55 , respectively, and an outer surface,  53  and  57 , respectively, opposing end walls  70  and  72  and arcuate projection wall  80  create a chamber for accommodating the LED light source (not depicted) of housing  20 . In a first embodiment of the present invention the chamber is substantially a rectangle and accommodates an LED light source in which the LEDs are arranged in a substantially lateral direction. 
   Turning to  FIG. 2  (a back perspective view), with reference to  FIG. 1 , arcuate projection wall  80  has a front surface  81  and a back surface  83 , which comprises a recessed projection channel  96 . In a first embodiment of the present invention, recessed projection channel  96  creates, and corresponds to, projection  90 . Accordingly, recessed projection channel  96  is a substantially elongated form and has a channel middle portion  95  and opposing channel side portions  97 , wherein the width of channel middle portion  95  is equally greater than the width of opposing channel side portions  97 . 
   As shown in  FIGS. 1 and 2 , in a first embodiment of the present invention, mounting walls  60  and  62  include mounting apertures  61  and  63 . Mounting apertures  61  and  63  are contiguous to mounting apertures within housing  20 , all which mounting apertures are designed to receive a screw, or other such mounting fixture, therethrough for affixing clearance marker  10  to a vehicle. 
   As shown in  FIGS. 1 and 2 , in a first embodiment of the present invention, recessed projection channel  96  and inner surfaces  51  and  55  of opposing side walls  50  and  54  can include longitudinally-spaced ribs, or grooves,  91  for increasing the dispersion of light from the LED light source. Additionally, in a first embodiment of the present invention, as shown in  FIG. 2 , back surface  83  of arcuate projection wall  80  can include reflective facets  85  arranged in a substantially segmented fashion for reflecting light to one or more sides of the vehicle. 
   Lens  30  and any components thereof can be made from any material that allows light to pass through it, such as, for example, any transparent or translucent material, including glass or plastics. In a first embodiment of the present invention, lens  30  is produced by forming a polycarbonate. 
   The dimensions of lens  30  and components thereof can be varied as desired to provide lenses for any size, shape or type of vehicle marker that meets the SAE standards. While a substantially rectangular-shaped housing and lens are depicted, the present invention can be used with any size and/or shape housing and lens including, for example, a circle, a beehive or a square. Furthermore, while the foregoing depicts a the present invention for use with a clearance marker, it should be understood that the present invention can be used with any type of vehicle marker, including, for example, a stop turn tail marker. Accordingly, it should be understood that the dimensions and proportions shown in  FIGS. 1 through 4  are provided for illustration purposes only and do not limit the invention to any particular dimensions or proportions. As shown in  FIGS. 3 and 4 , in a first embodiment of the present invention, clearance marker  10  and lens  30  have a width (W) of about 2 inches and a length (L) of about 6 inches. 
   As will be appreciated by those skilled in the art, lens  30  of the present invention provides for greater dispersion of light emitted from an LED light source in a substantially arc-like pattern. An LED is a directional light source in which the maximum light emitted in a direction perpendicular to the light surface. Lens  30  of the present invention includes a projection  90  that outwardly extends an area of the arcuate projection wall  80 , through which light is emitted from the LED light source, thereby permitting the light to be seen from a top view (as depicted in  FIG. 4 ) and bottom view (not depicted) of clearance marker  10 . 
   Additionally, according to a first embodiment of the present invention in which a recessed projection channel  96  formed within the back surface  83  of the arcuate projection wall  80  creates projection  90 , recessed projection channel  96  creates additional space in the light source chamber thereby permitting different arrangements of the LEDs. Typically, the LEDs in a clearance marker are arranged in a lateral direction and are directed outward, i.e., in a direction substantially perpendicular to the arcuate projection wall. According to a first embodiment of the present invention, the LEDs can be arranged so that the LEDs proximate the projection side portions  92  of projection  90  emit light in a direction substantially parallel to the arcuate projection wall. 
     FIG. 5  shows an embodiment of the invention wherein the lens comprises a substantially circular shape. Lens  100  comprises an arcuate projection  110  having a projection middle portion  111  and two projection side portions  112 , further comprising a plurality of grooves  113 . In accordance with the exemplary embodiment of the invention as shown, arcuate projection  110  is located opposite a plurality of LED&#39;s  500 . Whereas the embodiments shown and discussed herein comprise two side projection portions  92 ,  112 , as shown in  FIGS. 1 and 5 , it is to be understood that arcuate projection  90 ,  110  can include a different number of projection side portions  92 ,  112  as a matter of application specific to design choice without deviating from the scope of the invention. 
   The foregoing features of the present invention permit light emitting from an LED to be viewed from the side of a clearance marker. Accordingly, the present invention provides for a lens for use with an LED clearance marker which meets the requisite SAE standards for use as a side clearance marker while permitting the benefits enjoyed with using an LED light source. 
   Those skilled in the art will recognize that the apparatus of the present invention has many applications, may be implemented in many manners and, as such, is not to be limited by the foregoing exemplary embodiments and examples. In this regard, any number of the features of the different embodiments described herein may be combined into one single embodiment. Moreover, the scope of the present invention covers conventionally known and future developed variations and modifications to the apparatus described herein, as would be understood by those skilled in the art.