Patent Application
20250224088
The present application claims the benefit of German Patent Application No. 10-2024-100-194.1, filed Jan. 4, 2024, the disclosure of which is incorporated by reference.
The present invention relates to a lighting device for a motor vehicle.
A lighting device of the aforementioned type is known from DE 10-2021-122-953 B3. The lighting device described therein, which is designed in particular as a headlight for a motor vehicle, comprises a plurality of light sources from which light is emitted during operation of the lighting device, a collimating optics with a plurality of collimating lenses, each having an entry surface and an exit surface through which the light emitted from the light sources passes, and a secondary optics with a plurality of arrays of cylindrical lenses through which the light emitted by the collimating optics passes. In this case, the collimating lenses are arranged in at least two rows, wherein in each of the rows at least two of the collimating lenses are arranged next to one another in a first direction and wherein the rows are arranged next to one another in a second direction perpendicular to the first direction. An aperture is arranged on each of the entry surfaces of the collimating lenses, which is formed as an opening in an opaque layer on the entry surface. These apertures are designed differently for different rows. The lower edge of individual apertures on the entry surfaces of the collimating lenses can be imaged by the optics of the lighting device formed by the collimating optics and the secondary optics as a horizontal cut-off line into the exterior space of the motor vehicle. The three rows arranged one above the other disclosed in DE 10-2021-122-953 B3 can be used to generate a high beam, an apron component of a low beam and a range component of a low beam as different light functions.
A disadvantage of such lighting devices known from the state of the art is the different warm appearance with different functions, such as parts of a low beam and a high beam. Warm appearance here refers to the externally visible design of the lighting device during operation.
The problem underlying the present invention is therefore the creation of a lighting device of the type mentioned at the beginning, which has a constant warm appearance despite the generation of different light functions.
According to one embodiment, it is provided that at least one of the light sources, in particular each of the light sources, has a light exit surface with at least two separately controllable portions, wherein the lighting device is configured such that the light emitted from a first portion of the at least one light source generates a first light function and that the light emitted from a second portion of the at least one light source generates a second light function. This design makes it possible to generate a plurality of light functions with a series of collimating lenses arranged next to one another. Furthermore, a consistent warm appearance can be guaranteed.
It may be provided that the first light function is a high beam or part of a high beam and that the second light function is a low beam or part of a low beam. For example, the second light function may be the apron component of a low beam.
The at least two separately controllable portions of the at least one light source can be arranged next to one another in the light exit surface in a first direction and/or in a second direction, in particular wherein the first direction corresponds to a horizontal direction when the lighting device is installed in the motor vehicle and wherein the second direction corresponds to the vertical direction when the lighting device is installed in the motor vehicle.
It is possible that the optics of the lighting device formed by the collimating optics and the secondary optics are configured to image the light exit surface of the at least one light source into the exterior space of the motor vehicle. In particular, the second portion of the at least one light source may have an edge arranged in the light exit surface which faces the first portion of the at least one light source, wherein the optics of the lighting device are configured to image this edge of the second portion of the light exit surface of the at least one light source arranged in the light exit surface as a horizontal cut-off line into the exterior space of the motor vehicle. If the portion of the light source generating the second light function emits light and the adjacent first portion does not emit light, a sharp line between a luminous and a non-luminous area is automatically created. This sharp line is then imaged as a horizontal cut-off line into the exterior space of the vehicle. In this manner, apertures are no longer required to create a cut-off line, the boundaries of which must be imaged into the exterior space of the vehicle.
It may be provided that each of the separately controllable portions of the at least one light source is designed as a light-emitting diode (LED) or as a group of light-emitting diodes, the active surfaces of which together form the light exit surface of the at least one light source. At least one of the light sources, preferably each of the light sources, can be designed as a solid-state LED array. This allows the advantages of SSL technology to be utilized, which can consist in particular of a small installation space and high efficiency.
It is possible that at least one of the light sources, preferably each of the light sources, comprises two to six light-emitting diodes. Alternatively, more than six light-emitting diodes may be provided per light source. If there are two light-emitting diodes, the first and second portions each consist of one light-emitting diode. If there are more than two light-emitting diodes, the first and/or the second and/or optionally a further portion and/or optionally a plurality of further portions may have more than one light-emitting diode.
It may be provided that the active surfaces of the light-emitting diodes of the at least one light source, preferably the active surfaces of the light-emitting diodes of each of the light sources, have a size of 0.3 mm2 to 2.0 mm2, in particular have a size of 0.4 mm2 to 1.5 mm2, preferably have a size of 0.5 mm2 to 1.0 mm2. In particular, the total active surface area of the light-emitting diodes of a light source can be equal to 6 mm2 or less than 6 mm2 in size.
It is possible that one of the collimating lenses is assigned to each of the light sources in such a manner that the light emitted from the light source passes successively through the entry surface and the exit surface of the assigned collimating lens.
It may be provided that the at least one array of structures of the secondary optics is designed as an array of lenses. In particular, the lenses of the at least one array of lenses may be designed as cylindrical lenses, in particular wherein the cylindrical lenses are arranged next to one another in the first direction and the cylindrical axes of the cylindrical lenses extend in the second direction. This arrangement of the cylinder axes in a vertical direction achieves a horizontal spread of the light distribution generated by the lighting device.
The invention is discussed in more detail below with reference to the accompanying drawings. In the figures:
In the figures, identical or functionally identical parts are indicated with the same reference signs. A Cartesian coordinate system is shown in the figures for better orientation.
The embodiment of a lighting device according to the invention shown in the figures is designed as a headlight. The lighting device comprises a plurality of light sources 1, collimating optics 2 and secondary optics 3 (see
The light sources 1 are arranged in a row extending in a first direction X, next to one another and at a distance from one another (see
The light sources 1 each comprise a plurality of light-emitting diodes 4a, 4b, 4c, 4d, from which light is emitted during operation of the lighting device. The active surfaces of the light-emitting diodes 4a, 4b, 4c, 4d together form the light exit surface of the respective light source 1. At least one of the light sources 1, preferably each of the light sources 1, can be designed as a solid-state LED array.
In the illustrated embodiment example, each of the light sources 1 has two light-emitting diodes 4a, 4b arranged one above the other in the Y direction. These two light-emitting diodes 4a, 4b form a first portion 5 of the light source 1 for each of the light sources 1. Furthermore, for each of the light sources 1 in
It is quite possible to provide more or fewer light-emitting diodes 4a, 4b, 4c, 4d per portion 5, 6. Furthermore, it is possible to provide more than two portions 5, 6 of the light exit surface of the respective light source 1. For example, it may be provided that at least one of the light sources 1, preferably each of the light sources 1, comprises two to six light-emitting diodes 4a, 4b, 4c, 4d. Alternatively, more than six light-emitting diodes 4a, 4b, 4c, 4d may be provided per light source 1. If there are two light-emitting diodes 4a, 4b, 4c, 4d, the first and second portions 5, 6 each consist of one light-emitting diode 4a, 4b, 4c, 4d. If there are more than two light-emitting diodes 4a, 4b, 4c, 4d, the first and/or the second and/or optionally a further portion 5, 6 and/or optionally several further portions 5, 6 may have more than one light-emitting diode 4a, 4b, 4c, 4d.
It may be provided that the active surfaces of the light-emitting diodes 4a, 4b, 4c, 4d of the at least one light source 1, preferably the active surfaces of the light-emitting diodes 4a, 4b, 4c, 4d of each of the light sources 1, have a size of 0.5 mm2 to 1.0 mm2. In particular, the total active surface area of the light-emitting diodes of a light source can be equal to 6 mm2 or less than 6 mm2 in size.
The two portions 5, 6 of each of the light sources 1 or the light-emitting diodes 4a, 4b, 4c, 4d forming the portions 5, 6 can be controlled separately. When switched on, the light emitted by the light-emitting diodes 4a, 4b of the first portion 5 can generate a first light function, which is, for example, a high beam. Furthermore, when switched on, the light emitted by the light-emitting diodes 4c, 4d of the second portion 5 can generate a second light function which is, for example, a low beam or part of a low beam.
The embodiment of the collimating optics 2 shown in the figures is designed in one piece and is configured such that the light emitted by the light sources 1 passes at least partially through the collimating optics 2 during operation of the lighting device. In the embodiment shown, the collimating optics 2 has a row of three collimating lenses 7 arranged next to one another in the first direction X.
If more than one row of light sources 1 is provided, the collimating optics 2 will also have more than one row of collimating lenses 7. In this case, the rows of collimating lenses 7 are arranged in the same manner as the light sources 1 in the second direction Y or, in
It is quite possible to provide more than three or fewer than three collimating lenses 7 per row. It is also possible not to connect the collimating lenses 7 of the collimating optics 2 in one piece, but to form them on separate substrates, wherein the substrates can be arranged next to one another in the first and/or the second direction X, Y. This can result in a column-by-column division or a line-by-line or row-by-row division of the collimating optics 2 into a plurality of substrates.
The collimating lenses 7 each have an entry surface 8 facing the light sources 1 and an exit surface 9 opposite the entry surface 8. A collimating lens 7 is assigned to each of the light sources 1 and arranged in front of the light source 1 in such a manner that the light emitted by the light sources 1 is largely collimated by the collimating lens 7 assigned in each case.
In the illustrated embodiment example, the secondary optics 3 has a transparent substrate with an entry surface 10 and an exit surface 11, through which the light emitted by the collimating optics 2 can at least partially pass. It is quite possible to provide more than one transparent substrate of the secondary optics 3, through which the light emitted by the collimating optics 2 can at least partially pass in succession.
An array of structures, in particular an array of cylindrical lenses, can be arranged on the entry surface 10 and/or on the exit surface 11 of the secondary optics 3. In this case, the cylindrical lenses are arranged next to one another in the first direction X, wherein the cylindrical axes of the cylindrical lenses extend in the second direction Y. This arrangement of the cylindrical lenses achieves a horizontal spread of the light distribution generated by the lighting device into the exterior space of the motor vehicle.
The cylindrical lenses of the array may have a spherical or aspherical cross-section. They may also have a cross-section that corresponds to a portion of a sine function. Furthermore, the cylindrical lenses may have an angular or polygonal cross-section.
Instead of cylindrical lenses, the structures of the array may be designed as light deflection elements, in particular as prisms.
The optics of the lighting device formed by the collimating optics 2 and the secondary optics 3 image the light exit surfaces of the light sources 1 into the exterior space of the motor vehicle. In this case, the second portion 6 of the respective light source 1 has an edge 12 arranged in the light exit surface, which faces the first portion 5 of the respective light source 1. When the light-emitting diodes 4a, 4b of the first portion 5 are switched off and the light-emitting diodes 4c, 4d of the second portion 6 are switched on, this edge 12 of the second portion 6 arranged in the light exit surface is imaged by the optics of the lighting device as a horizontal cut-off line into the exterior space of the motor vehicle.
The above description is that of current embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. Any reference to elements in the singular, for example, using the articles “a,” “an,” “the,” or “said,” is not to be construed as limiting the element to the singular.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102024100194.1 | Jan 2024 | DE | national |
