LIGHTING DEVICE FOR A MOTOR VEHICLE

Abstract

A lighting device for a motor vehicle, wherein the lighting device comprises a printed circuit board having a plurality of light-emitting diodes arranged thereon, an optical disk and a reflector element, wherein the reflector element is arranged between the circuit board and the optical disk, wherein the reflector element has a plurality of segments into which the reflector element is divided, wherein each light-emitting diode is assigned a segment so that light emitted from the LEDs is reflected at the reflector element and passes through the optical disk.

Claims

1. A lighting device for a motor vehicle, the lighting device comprising: a printed circuit board having at least two light-emitting diodes arranged thereon; an optical disk; and a reflector element arranged between the printed circuit board and the optical disk, the reflector element having a plurality of segments into which the reflector element is divided, wherein each of the at least two light-emitting diodes is assigned a segment so that light radiated from the light-emitting diodes is reflected at the segments of the reflector element and passes through the optical disk, and wherein the segments have a triangular or substantially triangular shape.

2. The lighting device according to claim 1, wherein multiple segments are each combined into a repeating arrangement of rows and columns on the reflector element.

3. The lighting device according to claim 2, wherein the arrangements each have a rectangular or substantially rectangular shape.

4. The lighting device according to claim 1, wherein each light-emitting diode is assigned a segment such that light emitted from one light-emitting diode is reflected at the reflector element and passes through the optical disk in the region of the segment assigned to each of these light-emitting diodes.

5. The lighting device according to claim 1, wherein each segment of the reflector element is assigned a concave lens, which is arranged in each case between the reflector element and the optical disk.

6. The lighting device according to claim 5, wherein the concave lenses are formed in one piece with the optical disk.

7. The lighting device according to claim 5, wherein the concave lenses have a triangular or substantially triangular shape.

8. The lighting device according to claim 1, wherein the segments of the reflector element have at least a partially striped effect.

9. The lighting device according to claim 1, wherein a distance between the light-emitting diodes and the optical disk is less than 15 mm.

10. The lighting device according to claim 1, wherein the lighting device further comprises a grid mask which delimits the segments from each other.

11. The lighting device according to claim 1, wherein the lighting device further comprises a housing in which the printed circuit board, the reflector element and the optical disk are accommodated.

12. The lighting device according to claim 1, wherein the optical disk has optical scattering elements on its front and/or back.

13. A lighting system for a motor vehicle comprising a lighting device according to claim 1 and a control unit to control a light signature display of the lighting device.

14. The lighting system according to claim 13, wherein the lighting system comprises a plurality of lighting devices and the control unit is configured to control at least two of the plurality of lighting devices for displaying a common light signature.

15. A motor vehicle comprising a lighting device according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0034] FIG. 1 is a plan view of a lighting device according to an embodiment of the invention;

[0035] FIG. 2 is an oblique view of the lighting device from FIG. 1;

[0036] FIG. 3 is a side view of the lighting device from FIG. 1;

[0037] FIG. 4 is an oblique view of the lighting device from FIG. 1 without housing;

[0038] FIG. 5 is an exploded view of the lighting device from FIG. 1;

[0039] FIG. 6 is an oblique view of the lighting device from FIG. 1 without housing and without grid mask;

[0040] FIG. 7 is a detailed view of an arrangement of the lighting device from FIG. 1,

[0041] FIG. 8 is an oblique view of the circuit board of the lighting device from FIG. 1,

[0042] FIG. 9 is a plan view of the back of the optical disk of the lighting device from FIG. 1;

[0043] FIG. 10 is a plan view of an arrangement of concave lenses of the optical disk from FIG. 9;

[0044] FIG. 11 is an oblique view of the arrangement of the concave lenses from FIG. 10;

[0045] FIG. 12 is a schematic view of a section of the lighting device from FIG. 1 in operation;

[0046] FIG. 13 is the view from FIG. 12 with a solution for avoiding stray light in unlit segments;

[0047] FIG. 14 is a schematic view of a lighting system according to an embodiment of the invention in operation with different light signatures;

[0048] FIG. 15 is a schematic view of a lighting system according to a further embodiment of the invention in operation with a common light signature;

[0049] FIG. 16 is a schematic view of the lighting system from FIG. 9 in operation with a common light signature;

[0050] FIG. 17 is a schematic view of the lighting system from FIG. 9 in operation with another common light signature;

[0051] FIG. 18 is a schematic view of the lighting system from FIG. 9 in operation with yet another common light signature; and

[0052] FIG. 19 is a rear view of a motor vehicle according to an embodiment of the invention.

DETAILED DESCRIPTION

[0053] FIGS. 1 to 3 each show a lighting device 1 according to an example of the invention in a plan view, a perspective view and a lateral view.

[0054] The lighting device 1 comprises a housing 4, which is formed in the present case as a housing frame having an upper part 2 and a lower part 3. The housing 4 has a small thickness as compared to its width and height extension. The housing 4 is in the present case, in particular in the upper part 2, for example, rectangular, in particular square, so that the lighting device 1 has an overall rectangular shape. Alternatively, however, the housing 4 or the lighting device 1 may also have other shapes, such as rectangular, round or oval.

[0055] As can be seen from FIG. 1, the lighting device 1 comprises a plurality of arrangements 5, each comprising a plurality of segments 6. In the present case, the arrangements 5 are formed square in their basic shape or appearance on the optical disk 8 (see FIG. 5) of the lighting device 1 and each comprise four triangular segments 6. The individual segments 6 can be illuminated individually and evenly by means of light-emitting diodes 11 (see FIG. 5) arranged behind them.

[0056] FIG. 4 shows in a perspective view of the lighting device 1 without housing 4 that the light-emitting diodes 11 (see FIG. 5) are arranged for this purpose on a circuit board 10 or board 5 and behind a reflector element 9. Behind the circuit board 10, also a rear part 12 of the housing 4 can be seen, which allows for the closing of the housing 4 from the back.

[0057] FIG. 5 shows the lighting device 1 in an exploded view, from which it can be inferred that the reflector element 9 has the segments 6 arranged in the arrangements 5 and the repeating arrangements 5. The reflector element 9 is arranged in the present case in one piece with all arrangements 5 and segments 6. Alternatively, the segments 6 can also be produced individually, but this is more complex.

[0058] The reflector element 9 is arranged on the circuit board 10 with the light-emitting diodes 11. In each case, a light-emitting diode 11 is assigned to a segment 6 in the reflector element 9 or each segment 6 surrounds one of the light-emitting diodes 11 on the circuit board 10.

[0059] On the reflector element 9, in turn, an optical disk 8, for example made of glass or plastic, is arranged. On the optical disk 8, in turn, a grid mask 7 is arranged, which provides an optical separation of the segments 6 from each other. All of the aforementioned components are included in the housing 4.

[0060] FIG. 6 shows an oblique view of the lighting device 1 without housing 4, without optical disk 8 and without grid mask 7. It can be seen here how each light-emitting diode 11 (not directly visible) is arranged within each segment 6 or is surrounded by the segment 6, which can illuminate the light-emitting diode 11.

[0061] FIG. 7 shows a detailed view of an arrangement 5 with four triangular segments 6, which are arranged in the square arrangement 5 on the printed circuit board 10. Each of the segments 6 has three mutually angled reflector surfaces or walls, on each of which a striped effect 13 is formed in proximity to the respective light-emitting diode 11 assigned to the segment 6. The corners of the segments 6 are rounded. The segments 6 extend from the respective light-emitting diode 11 in the direction of the optical disk 8 with an opening close to the light-emitting diode 11, which allows for the irradiation of light from the light-emitting diode 11 to the reflector surfaces, to a larger opening, from which the light then exits onto the optical disk 8, through which it then in turn passes through.

[0062] FIG. 8 shows an oblique view onto the printed circuit board 10 with the LEDs 11. As can be seen, the light-emitting diodes 11 are arranged here in a repeating plus arrangement corresponding to the arrangements 5 on the circuit board 10.

[0063] FIG. 9 shows a plan view of the back of the optical disk 8 of the lighting device 1, i.e., the side facing the reflector element 9. Here it can be seen that the optical disk 8 has a plurality of concave lenses 14 formed on its back, each of which is triangular and arranged in accordance with the arrangement 5 of the segments 6 on the optical disk 8, so that each lens 14 is assigned to a segment 6 or located opposite thereto.

[0064] FIGS. 10 and 11 show the concave lenses 14 in a plan view and an oblique view in an arrangement with four concave lenses 14. Here it is particularly easy to see that the lenses 14 each have a concave, central surface, which accordingly have a greater distance to the light-emitting diode 11 assigned to it by means of the segment 6. Their shape corresponds to a pyramidal look, so that by comparison the lenses in their outer area have a larger wall thickness. This is advantageous for uniform illumination without emphasizing an axial light-emitting diode intensity (especially with so-called top LEDs) and thus allows for illumination of the segment 6 or the area of the optical disk 8 in front of segment 6 without a hotspot.

[0065] FIG. 9 shows a section of the lighting device 1 in a cross-sectional view. An example of a section of a printed circuit board 10 with three light-emitting diodes 11 and wall elements or reflector surfaces of segments 6 of the reflector element 9 can be seen here. Finally, the grid mask 7 is located behind the optical disk 8.

[0066] The distance between the light-emitting diodes 11 and the optical disk 8 is particularly small, for example, is only 10 cm or less to achieve the compactness or small thickness of the lighting device 1 mentioned above. Accordingly, there is little space for the corresponding reflector element 9 or corresponding reflections. At the same time, however, the most uniform illumination of the respective segment 6 or area of the optical disk 8 in front of the respective segment 6 must be achieved.

[0067] To ensure this, as already explained, the concave lenses 14, which are formed by way of example in one piece with the optical disk 8, are used in the present case. The lenses 14 also include a light guide effect and, in the interaction of the prism surfaces of the lenses 14 and the surrounding reflector surfaces of the segments 6, also an additional light guidance, which together with the central illumination of the concave lens surface leads to a homogeneous illumination of the segment 6.

[0068] Now, as FIG. 13 shows in a further view, it can come to a deflection of light from one segment 6 to another segment 6 between the light-emitting diodes 11 and the reflector element 9 or the segments 6. This can also be referred to as stray light. The problem with this stray light is that segments 6 not actively illuminated by a light-emitting diode assigned to a segment 6 are nonetheless illuminated to a lesser extent. As a result, the desired light signature display of the lighting device 1 is compromised.

[0069] In order to solve this problem, a screen 15, in particular a passive LC display, is arranged on the front or visible side of the optical disk 8, which is formed in the present case by way of example from a first thin substrate 15 and a second thin substrate 16 and a liquid crystal in between. The substrates 15, 16 may be, for example, glass panes or plastic films.

[0070] Now the screen 15 is, in particular, a so-called dye-doped display, in which the color pigments of the screen 15 are doped. In the non-operating state of the screen 15, the color pigments, which may be, for example, black, determine the color of the screen 15.

[0071] The screen 15 is now programmed or control-technically configured with the LEDs 11 or the board 10 so that the screen 15 remains switched off or non-transparent in the region of those segments 6 or opposite of segments 6 to which associated light-emitting diodes 11 are not activated, so that only the predetermined color pigments can be seen, for example, black. As a result, no stray light can be seen from the outside in the non-active segments 6, even if it hits the optical disk 8 there.

[0072] Again, the screen 15 is programmed or control-technically configured to switch on opposite those segments 6, which are illuminated by switching on the light-emitting diodes 11, in order to switch the screen 15 to transparent in this area opposite the segment 6, as can be seen in FIG. 13. As a result, the light of the light-emitting diode 11 of this segment 6 can escape from the optical disk 8 or the lighting device 1 and be perceived optically.

[0073] FIG. 14 shows schematically a lighting system 20 with several, in the present case purely by way of example four, lighting devices 1. The lighting devices 1 may be controllable by means of individual or, as shown, a common control unit 21.

[0074] In FIG. 14, different light signatures are shown, which are displayed by the respective lighting devices 1. Individual contents or symbols are reproduced by means of the light signatures, such as a cross for a stop, a walking pedestrian or a standing pedestrian.

[0075] When using light-emitting diodes 11, which cover the color spectrum (yellow, red, blue), a division of the area of a lighting device 1, for example with a larger red area (red light-emitting diodes) and a smaller yellow area (yellow light-emitting diodes) or another color distribution is possible. As a result, two functions, e.g., taillight and direction indicator, or three functions, e.g., tail brake light and direction indicator, can be realized.

[0076] However, it is also possible to match the light signatures of the individual lighting devices 1. For example, FIG. 15 shows three lighting devices 1 of a lighting system 20, each showing the same light signature.

[0077] FIGS. 16 and 17 each show a different and self-contained or common light signature, which is generated in sequence or series connection of four lighting devices 1 together jointly by the latter.

[0078] FIG. 18, in turn, shows a repetition of a light signature on four lighting devices 1 of a lighting system 20, wherein the light signature occupies a usable indication function, for example, in driving of the motor vehicle equipped with the lighting system 20, namely the display of a right arrow, which can also be referred to as a driving indicator and can be used, for example, for driving the motor vehicle 30 equipped with it (see FIG. 14) to the right.

[0079] FIG. 19 shows a motor vehicle 30 according to an embodiment of the invention in a rear view. The motor vehicle 30 is each configured with the lighting systems 20 described above, which are configured in the present case as rear lights of the motor vehicle 30 and thus enable the display of various common or different light signatures, for example a turning by means of corresponding arrow representations as light signatures.

[0080] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.