Light manifold for automotive light module

[0001] 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.

[0002] Light emitting diodes (LED'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'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.

[0003] Accordingly, there exists a need to provide methods and structures for light distribution which meets the requirements of specialized applications.

[0004] 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.

[0005] 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.

[0006] 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.

[0007] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] Turning now to FIGS. 6 and 6a, 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 222a and a second body portion 222b which are similarly constructed. Each main body portion 222 includes a first reflecting surface 226 and a second emitting surface 224.

[0023] As best seen in FIG. 6a, 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.

[0024] 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.

[0025] 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.