Abstract:
A light manifold for an automotive light module emitting light to the side of a longitudinal axis along which light is to be directed. The light module is structured in a manner that permits the creation of light distribution patterns for particular functions, such as the stop light function for an automobile, that are otherwise difficult to effectively produce.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to automotive light modules and light manifolds therefor, and more particularly relates to light manifolds for near field lenses collecting and directing light laterally relative to the light source. 
     BACKGROUND OF THE INVENTION 
     Light emitting diodes (LED&#39;s) are fast becoming a preferable light source for automotive lighting applications, as they consume less power but provide light output which is acceptable for such applications. In order to employ LED&#39;s for automotive applications, high levels of efficiency must be obtained in both light collection as well as light distribution. Typically, reflectors or lenses or light pipes are utilized to collect and distribute the light for the particular lighting application. Unfortunately, not all automotive applications, such as the stop function of a tail light, have been effectively produced utilizing an LED light source in such reflectors, lenses or light pipes. 
     Accordingly, there exists a need to provide methods and structures for light distribution which meets the requirements of specialized applications. 
     BRIEF SUMMARY OF THE INVENTION 
     One embodiment of the present invention provides a light manifold for a light module which facilitates reproduction of automotive light functions. Generally, the light manifold distributes light from a light source and includes the main body of light transmitting material. The main body defines a longitudinal axis and a lateral axis. The main body has opposing first and second surfaces, the first and second surfaces generally facing longitudinally. The first surface has a series of alternating angled portion and lateral portions. The angled portions are angled relative to both the longitudinal and lateral axes for reflecting light towards the second surface. The lateral portions include a plurality of ridges structured to reflect incident light towards the second surface. 
     According to more detailed aspects, the lateral portions are generally parallel to the lateral axis and preferably are angled about 45 degrees relative to both the longitudinal and lateral axes. Each angled portion has an upper longitudinal edge and the plurality of ridges have upper longitudinal edges positioned lower than the upper longitudinal edge of an adjacent radially inward angled portion. Preferably, the plurality of ridges are defined by V-shaped grooves formed into the first surface of the main body. The angled portions are positioned sequentially in the longitudinal direction. The main body preferably includes a lateral facing surface receiving light from the light source, and preferably from a near field lens positioned inside the main body and having a flat outer laterally facing surface abutting against the laterally facing surface of the main body. 
     Another embodiment of the light manifold constructed in accordance with the teachings of the present invention includes a main body of light transmitting material and having a disc shape defining a longitudinal axis. The main body has opposing first and second surfaces generally facing longitudinally. The main body is circumferentially divided into a plurality of wedge sections, each wedge section having a series of radially spaced apart angled portions formed into the first surface. The angled portions are angled relative to the longitudinal axis for reflecting light towards the second surface. The radial spacing of the angled portions of the first wedge section are different than the radial spacing of the angled portions of a second wedge section. 
     According to more detailed aspects, each wedge section has a radial length, and the radial length of the first wedge section is different than the radial length of the second wedge section. Preferably, the plurality of wedge section alternate between the first and second wedge sections. Each wedge section further includes a series of radially spaced apart inclined sections, the inclined sections being angled relative to the longitudinal axis at a degree greater than the degree the angled sections are angled relative to the longitudinal axis. For example, the angled sections may be angled at about 45 degrees while the inclined sections are angled greater than about 45 degrees, and preferably at about 68 degrees. The radially outer most angled portion may be shared by all wedge sections. As with the prior embodiment, the plurality of angled portions are spaced apart radially and positioned sequentially in the longitudinal direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings: 
         FIG. 1  is a perspective view of a light manifold constructed in accordance with the teachings of the present invention; 
         FIG. 2  is side view of the light manifold depicted in  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of the light manifold depicted in  FIGS. 1 and 2 ; 
         FIG. 4  is a perspective view, partially cut-away, of another embodiment of the light manifold constructed in accordance with the teachings of the present invention; 
         FIG. 5  is cross-sectional view of the light manifold depicted in  FIG. 4 ; and 
         FIGS. 6 and 6   a  are a side view and an enlarged portion of the side view of another embodiment of a light manifold constructed in accordance with the teachings of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning now to the figures,  FIGS. 1–3  depict a light manifold  20  for use with the light module having a near field lens  10  and light source  11 . Generally, the light manifold includes a disc-shaped main body  22  constructed of a light transmitting material, and preferably a plastic such as acrylic although any light transmitting material may be employed. The main body  22  defines a longitudinal axis  14  along which light is directed, and a lateral axis  16  perpendicular to the longitudinal axis  14 . As used herein, the lateral direction may also be referred to as the radial direction, and encompasses all directions which are generally transverse to the longitudinal axis  14 . The main body includes a light emitting surface  24  and a light reflecting surface  26 . The light reflecting surface  26  will be referred to herein as the first surface  26  and the light emitting surface  24  will be referred to as the second surface  24 . The main body  22  also includes an inner laterally facing surface  25  defining a pocket receiving the near field lens  10 . Generally the inner laterally facing surface  25  is flat and annular, corresponding to the flat and annular outer surface of the near field lens  10 . 
     The main body  22  of the manifold  20  receives light from the light source  11  and near field lens  10  through the inner laterally facing surface  25  for further redirection by the first surface  26 . The near field lens  10  is preferably constructed as a side-emitting NFL, one preferred construction being described in copending U.S. patent application Ser. No. 11/274,071 filed on Nov. 15, 2005 concurrently herewith, the disclosure of which is incorporated herein by reference in its entirety. Generally, the NFL  10  is structured to collect, longitudinally collimate and redirect the light laterally along the lateral axis  16 , and may be separately formed or integrally formed with the manifold  20 . The first surface  26  includes a series of alternating angled portions  28  and lateral portions  30 . The angled portions  28  are angled relative to both the longitudinal and lateral axes for reflecting light towards the second surface  24 . Preferably, the angled portions  28  are angled at about 45 degrees although a wide variety of angles may be employed to provide a certain beam spread or pattern depending on the particular automotive function desired. The lateral portions  30  are generally parallel to the lateral axis  16 , and therefore typically do not reflect the light. By the terms generally and about, it is meant that the surfaces are generally within 3 degrees of perfectly parallel or perpendicular. It will also be seen that the angled portions  28  are positioned sequentially moving in the longitudinal direction (i.e. along axis  14 ) to redirect the light longitudinally at different lateral or radial positions. 
     As best seen in  FIGS. 1 and 2 , the main body  22  includes a plurality of wedge sections, which here have been depicted as alternating first wedge sections  32  and second wedge sections  34 . The first and second wedge sections  32 ,  34  span different radial lengths. Similarly, the first and second wedge sections  32  also include alternating angled portions  28  and lateral portions  30  which are positioned at different radial locations. It can also be seen that the first and second wedge sections  32 ,  34  include different numbers of angled portions  28 . For example, the first section  32  has been depicted as having three angled portions  28 , while the second wedge section  34  has been depicted as having only two angled portions  28 . 
     Accordingly, it will be recognized that those skilled in the art that the light manifold  20  may be constructed out of any number of different wedge sections  32 ,  34  having any number of different angled portions  28  which can also be positioned at various radial positions and at various angles. All of these variables thus provide increased adaptability and the opportunity for uniquely creating a light distribution pattern or beam spread which achieves a certain function or application, like a particular light assembly of an automobile such as a stop light, brake light, turn light or the like. 
     Turning now to  FIGS. 4 and 5 , another embodiment of the light manifold  120  has been constructed in accordance with the teachings of the present invention. As with the prior embodiment, the light manifold  120  includes a main body  122  having a first surface  126  for redirecting light through a second surface  124 . The main body  122  defines an inner laterally facing surface  125  receiving light from a light source  111  having a side emitting NFL. The main body  122  is circumferentially divided into a plurality of first and second wedge sections  132 ,  134  each having slightly different constructions. As with the prior embodiment, the first surface  126  is structured to include a plurality of alternating angled portions  128  and lateral portions  130 . 
     Unlike the prior embodiment, the first surface  126  also includes a plurality of inclined portions  129  positioned between the angled portions  128  and lateral portions  130 . The inclined portions  129  are angled at some degree relative to the longitudinal axis that is greater than the angle of the angled portions  128 . Preferably, the inclined sections  129  are angled at about 68 degrees relative to the longitudinal axis  14 . Thus, the first surface  126  follows a series including the angled portion  128 , lateral portion  130  and inclined portion  129 . In this manner, light is passing laterally through the main body  122  that strikes an inclined portion  129  will be redirected towards an angled portion  128  and reflected outwardly through the second surface  124 , at some increased angle relative to the longitudinal axis  14 . Accordingly, it will be recognized by those skilled in the art that through the provision of inclined portions  129 , a controlled amount of beam spread is provided by the light manifold  120 . 
     The first and second wedge sections  132 ,  134  differ in their radial spacing and size of angled portions  128 , inclined portions  129  and lateral portions  130 . Like the prior embodiment, increased control is provided over the resulting beam pattern through the use of different wedge sections  132 ,  134 . It will also be recognized that the radially outer most angled portion  128  is shared by all of the first and second wedge sections  132 ,  134 . As such, a solid ring of light is provided along the outer periphery and a common outer diameter to the main body  122  is provided. 
     Turning now to  FIGS. 6 and 6   a , another embodiment of a light manifold  220  constructed in accordance with the teachings of the present invention has been depicted. The manifold  220  of this embodiment is structured for use with a near field lens  210  having a bi-directional lens construction, which is described in more detail in copending U.S. patent application Ser. No. 11/274,071 filed concurrently herewith. The NFL  210  is structured to direct light in two laterally opposite directions along a longitudinal axis  16 . Accordingly, the manifold  220  includes a first body portion  222   a  and a second body portion  222   b  which are similarly constructed. Each main body portion  222  includes a first reflecting surface  226  and a second emitting surface  224 . 
     As best seen in  FIG. 6   a , and similar to prior embodiments, the first surface  226  includes alternating angled portions  228  and lateral portions  230 . However, in this embodiment, the lateral portions  230  include a plurality of ridges  229  structured to reflect incident light towards the second surface  224 . In this manner, light distribution efficiency is improved. As shown in the figure, the angled portion  228  includes an upper longitudinal edge  231  and the plurality of ridges each have an upper longitudinal edge  233 . Generally, the lateral portion  230  and the upper edges  233  of the ridges  229  are positioned below the upper longitudinal edge  231  of the angled portion  228 . In this manner, the lateral portion  230  is somewhat shielded by the angled portion  228 , and therefore only collects non-collimated or other incident light. It will also be recognized that the second light emitting surface  224  includes a plurality of dimples  227  which are structured to focus certain portions of the emitted light. Preferably, the dimples  227  are positioned in lateral alignment and longitudinally above the angled portions  228 . It will be recognized that any number of different beam focusing or spreading optics may be employed on the second surface  224  of the light manifold  220 . 
     Accordingly, it will be recognized by those skilled in the art that the various light manifold constructions described herein provide numerous opportunities for customization and hence constructions which can address particular light distribution requirements such as for automotive functions. 
     The foregoing description of various embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Numerous modifications or variations are possible in light of the above teachings. The embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.