Device for interior lighting of a motor vehicle

Abstract

A device for interior lighting of a motor vehicle, comprising one or more light guide bundles (3) made up of a plurality of light guides (8), wherein first ends of the light guides (8) of a respective light guide bundle (3) are combined to form a light coupling surface (5) and light coupled at the light coupling surface (5) is coupled out at second ends (2) of the light guides (8) opposite the first ends in order to illuminate the interior (I) of the motor vehicle, wherein the second ends (2) of the light guides (8) are positioned in an interior trim panel (1) for the motor vehicle such that each second end (2) forms a light point on the interior trim panel (1) when light exits there, illuminating the interior, characterized in that a plurality of light sources (701, 702, 703, 704) with different emission colors are provided at the light coupling surface (5) of a respective light guide bundle (3),which can be controlled by means of a control device (9), wherein the light sources (701, 702, 703, 704) are arranged such that they shine light into different areas of the light coupling surface (5) during operation.

Description

[0001] The invention relates to a device for interior lighting of a motor vehicle.

[0002] Various lighting concepts for motor vehicles are known from the prior art, which generate pleasant ambient interior lighting for the vehicle occupants. For example, in some vehicles, a large number of LEDs are arranged in the headliner, which, when activated, represent individual points of light, preferably distributed unevenly in the headliner. Instead of generating the points of light with individual LEDs, it is also known to integrate a large number of light guides distributed throughout the headliner of a motor vehicle. The points of light are formed by the ends of the light guides, which are arranged in the headliner. Light from a light source, in particular an LED, is shone into the opposite ends of the light guides. With the known interior lighting systems, only limited appealing visual effects can be generated for the vehicle occupants.

[0003] German patent application DE 10 2008 036 616 A1 describes a surface projection system for imaging a visual signal onto a surface. In this system, light is shone into one or more optical fiber bundles consisting of a plurality of optical fiber elements. The ends of the optical fiber elements, positioned opposite the direction of the light incidence, are connected to a support element. The resulting bright points are projected onto a surface, for example, the surface of an aircraft, by means of an imaging optic.

[0004] Document DE 10 2007 014 871 A1 discloses a lighting device, particularly for vehicles. The lighting device comprises at least two semiconductor light sources emitting light of different colors, and at least one optical fiber into which the light from the semiconductor light sources is coupled. Furthermore, a light-mixing device with a transparent, refractive element is provided at the entrance to the optical fiber. This device mixes the spatial distribution of the light from the light sources, producing light that is a superposition of the colors of the semiconductor light sources. The light-mixing device is, for example, designed as a light-guiding rod.

[0005] Document DE 20 2006 006 663 U1 describes a fiber optic light projector with a controllable light source arranged in a housing, comprising several optical fibers forming a fiber bundle. The light projector is used in particular for generating point or line-shaped light effects on ceilings, walls, or for product presentation in an exhibition space.

[0006] German patent application DE 10 2010 003 273 A1 discloses a vehicle interior lighting system with a light guide into which the light from at least one light source is directed. The light from the light source is modified with regard to color and / or brightness depending on bus data transmitted via the vehicle system bus.

[0007] Document DE 10 2010 013 819 A1 describes a motor vehicle with an interior lighting device. The lighting device comprises a light-guiding element with an input surface for coupling light from a light source and an output surface through which the light exits the light-guiding element. The light-guiding element is recessed in such a way that light emitted from the output surface does not directly enter the area of ​​the vehicle's interior where the eyes of a vehicle occupant are located.

[0008] Document DE 44 39 547 A1 discloses a lighting system for the interior of a motor vehicle according to the preamble of claim 1.

[0009] The German patent application DE 203 12 260 U1 describes a decorative element with light effects achieved using embedded optical fibers into which light from matrix-arranged LEDs of different colors is coupled. The LEDs are powered by a battery and operated via a push-button module. The optical fibers can be integrated, for example, into a wig, a stuffed animal, a doll's head, or a man's beard to create light effects.

[0010] Document WO 2009 / 089 109 1A discloses a device for interior lighting of a motor vehicle in which the light from LEDs of different colors is shone into an optical fiber system via a light coupler that mixes the light from the LEDs.

[0011] German patent application DE 10 2004 016 130 A1 discloses a lighting device with a light source that shines its light into a light guide element, which then emits light to a mask arranged above the light guide element and having areas of varying transparency. The light guide element is formed by several optical fibers, with the light source shining its light into the optical fibers via at least some of their end faces.

[0012] Document DE 10 2005 016 116 A1 describes a luminaire comprising at least one light source, a plurality of light guide means suitable for transporting the light emitted by the at least one light source, wherein the luminaire has a housing with a plurality of light emission openings, wherein at least one of the light guide means is installed in each of the light emission openings.

[0013] German patent application DE 10 2006 002 336 A1 discloses an interior lighting system for a vehicle whose interior is fitted with a trim panel. In through-openings of the trim panel, one end of a light guide protrudes, such that an end face of the respective light guide is flush with an outer surface of the trim panel, and one or more light guides can be illuminated by a central light source.

[0014] The object of the invention is to create a device for interior lighting of a motor vehicle with which a visually appealing light distribution can be generated in a simple manner.

[0015] This problem is solved by the device according to claim 1. Further developments of the invention are defined in the dependent claims.

[0016] The device according to the invention serves for interior lighting of a motor vehicle, and in particular a passenger car. The device comprises one or more light guide bundles made up of a plurality of light guides, which are preferably designed as optical fibers. Light is guided in the light guides by means of total internal reflection. In the device according to the invention, the first ends of the light guides of a respective light guide bundle are combined to form a light coupling surface. Light coupled at the light coupling surface couples out at second ends of the light guides, opposite the first ends, in order to illuminate the interior of the motor vehicle when the device is installed there.

[0017] The device according to the invention is characterized in that a plurality of light sources with different emission colors are provided on the light coupling surface of a respective light guide bundle, which can be controlled by means of a control device. The light sources are arranged such that, during operation, they shine into different areas (i.e., cross-sectional areas) of the light coupling surface. The term "different areas" means that each area differs at least partially and, if necessary, completely (i.e., without overlaps) from another area.

[0018] According to the invention, several light sources with different emission colors are assigned to a single optical fiber bundle. An emission color is understood to be an emission wavelength or spectral emission wavelength band that is perceived by a user as a corresponding color. The emission wavelengths or spectral bands are (at least partially) different for the individual light sources. By using different colored light sources that shine into different areas of the light coupling surface, light with different colors, and optionally with mixed colors, emerges from the other ends of the optical fibers. In this way, attractive lighting can be generated in the interior of the vehicle.

[0019] According to the invention, the second ends of the light guides are positioned in an interior trim panel for the motor vehicle, and in particular in a roof panel, such that each second end, when emitting light, forms a point of light on the interior trim panel, illuminating the interior. Preferably, the second ends of the light guides of each light guide bundle are distributed in the interior trim panel or the roof panel, with the distribution preferably being uneven. For example, the second ends of the light guides of the individual light guide bundles can be distributed in respective "squares" of the roof panel, with the individual squares slightly overlapping. In this way, an effective light distribution resembling a starry sky can be generated, with the stars being represented by the corresponding second ends of the light guides.

[0020] In a further, particularly preferred embodiment, the light sources comprise LEDs (LED = Light Emitting Diode), such as OLEDs (OLED = Organic Light Emitting Diode), wherein preferably each light source of the plurality of light sources is an LED. By using LED technology, the lighting device can be designed to be particularly space-saving and energy-efficient. In one variant of the invention, the maximum total power of the plurality of LEDs of a respective light guide bundle is approximately 3 W.

[0021] In a further embodiment of the device according to the invention, the light sources are arranged on the light coupling surface such that light from several light sources enters at least a portion of the light guides on the light coupling surface. This ensures that a mixing of the emission colors is achieved in certain light guides, thereby increasing the color palette of the light emitted by the interior lighting.

[0022] In a particularly preferred embodiment, the plurality of light sources provided for a respective light guide bundle comprises at least one light source with red emission color and / or at least one light source with green emission color and / or at least one light source with blue emission color and / or at least one light source with white emission color.

[0023] In a particularly preferred embodiment of the invention, exactly four light sources are provided for each optical fiber bundle, emitting light with red, green, blue, and white emission colors. Preferably, the four light sources are arranged such that two pairs of light sources are positioned offset from one another in a first direction along the light coupling surface, with the light sources of each pair being arranged side by side in a second direction along the light coupling surface, which is perpendicular to the first direction. In particular, the light sources are arranged in a square, and the light sources themselves may optionally have square emission surfaces.

[0024] In a further embodiment of the device according to the invention, one or more optical elements are arranged between the light coupling surface and the plurality of light sources, in particular one or more diffusers (e.g., made of frosted or ground glass) and / or one or more optical filters and / or one or more prisms and / or one or more optical elements with a prismatic surface and / or one or more optical elements, each having areas with different light transmittances. In this way, further optical effects can be generated. Preferably, one or more of the optical elements are displaceable and / or rotatable by means of the control device, in particular along or about an axis perpendicular to the light coupling surface. This provides a corresponding mechanism for displacing or rotating the optical elements.Furthermore, it may be possible to vary the distance between the light coupling surface and the majority of light sources using the control device. In this case, a corresponding mechanism for varying this distance is also provided.

[0025] In a particularly preferred embodiment, the control unit can vary the brightness of the activated light sources of a respective light guide bundle. Preferably, the brightness of each light source can be adjusted independently of the other light sources in that same light guide bundle. Alternatively or additionally, if multiple light guide bundles are present, it is also possible to adjust the majority of light sources within each bundle independently. In this way, the control unit can generate a wide variety of visual effects in the vehicle interior.

[0026] In a further embodiment of the device according to the invention, the control unit regulates the brightness of the light sources of a respective light guide bundle depending on the signals of one or more sensors in the vehicle, e.g., depending on one or more vehicle acceleration sensors and / or vehicle speed sensors and / or temperature sensors (e.g., for measuring the interior or exterior temperature) and / or acoustic sensors, which in particular detect the signal (preferably music) emitted by the vehicle's audio system in the vehicle interior. This allows the light distribution of the lighting device to be adapted to the current driving condition of the vehicle.

[0027] In another embodiment, the lighting control unit can be operated via a user interface, which is preferably integrated into a mobile device that communicates wirelessly with the control unit, e.g., via Bluetooth or WLAN. This allows the vehicle occupants to adjust the lighting to their needs. Alternatively, the user interface can be permanently integrated into the vehicle, enabling operation of the control unit via vehicle input devices or a vehicle screen.

[0028] In a further embodiment of the invention, the second ends of the optical fibers of a respective optical fiber bundle are arranged at least partially at positions spaced apart from one another. In this way, the light from the interior lighting can be distributed over a large area of ​​the interior. In particular, this allows for the creation of a large number of illuminated light points.

[0029] In addition to the lighting device described above, the invention further relates to a motor vehicle which includes one or more of these lighting devices.

[0030] Exemplary embodiments of the invention are described in detail below with reference to the accompanying figures.

[0031] They show: Fig. 1 a perspective view of the interior of a vehicle with a variant of the interior lighting according to the invention; Fig. 2 a side view of a light guide bundle and corresponding LEDs at the light coupling surface according to an embodiment of a lighting device according to the invention; and Fig. 3 a top view of the coupling surface of the optical fiber bundle made of Fig. 2.

[0032] The embodiment of the invention described below is illustrated by an interior light integrated into the headliner of a motor vehicle. This lighting device can create visually appealing effects and convey the impression of a realistic starry sky with varying colors and intensities. Fig. Figure 1 shows a perspective view of the interior I of a vehicle, which includes the lighting system integrated into the headliner. The headliner is labeled with reference symbol 1 and comprises numerous black-indicated light points 2, which, for clarity, are only partially labeled with this reference symbol. Each individual light point represents one end of a light guide or optical fiber, from which light of varying colors and intensities can emerge. The individual ends of the light guides are unevenly distributed in the headliner to enhance the effect of a starry sky. The light guides are installed behind the headliner, with a specific number of light guides forming a light guide bundle.This bundle of light guides is brought together at the ends of the light guides that are opposite to ends 2, forming a coupling surface there, as described below in relation to . Fig. 2 and Fig. 3 will be explained in more detail. Light of different colors is shone into the individual light guides via this coupling surface using several LEDs.

[0033] Fig. Figure 2 shows a side view of one of the light guide bundles of the interior lighting. Fig. 1, which is combined to form a light coupling surface. The area of ​​the optical fiber bundle where light coupling occurs is shown. The optical fiber bundle is designated by reference numeral 3 and is surrounded by a cylindrical sheath that holds the individual optical fibers together. The sheath is only provided in a section of the optical fiber bundle. In the area without a sheath, the individual optical fibers are then routed to different positions in the headliner. Fig. 1. The optical fiber bundle 3 terminates in a metallic connector 4, at the front end of which is a light coupling surface 5, at which light can be coupled into the corresponding ends of the optical fibers of the optical fiber bundle. The connector 4 terminates in a metallic socket 6, in which four LEDs arranged in a square are located as light sources, as shown in the view of the Fig. Only LEDs 701 and 702 are visible. The other LEDs, 703 and 704, are off. Fig. 3. The plug head 4 and the socket 6 may also be made of a non-metallic material.

[0034] The light from the LEDs couples into the coupling surface 5 of the light guide bundle 3. A key aspect of the invention is that several LEDs are provided per light guide bundle and that the LEDs emit light in different colors. That is, the LEDs emit light in different spectral bands, with each LED emitting in a spectral band perceived by the human eye as a separate color. The individual LEDs are controlled by a control unit 9, which is shown only schematically. The control unit also serves to control the LEDs of other light guide bundles in the lighting device. The brightness of the individual LEDs can be varied using the control unit 9. The number of light guide bundles used can be selected differently depending on the design of the lighting device. In the Fig. For example, 16 fiber bundles can be used in the lighting device shown in Figure 1, each comprising approximately 80 individual light guides.

[0035] As can be seen from Fig. As shown in Figure 2, the light coupling surface 5 is arranged at a distance from the corresponding LEDs 701 and 702. This distance can be selected differently depending on the embodiment and may also be variable. Furthermore, in a preferred embodiment of the invention, it is possible to arrange one or more optical elements between the light coupling surface and the LEDs, with which special effects (e.g., in the manner of a kaleidoscope) can be generated. As mentioned above, such optical elements can be diffusers, optical filters, prism arrangements, and the like. Optionally, the optical elements can be rotated about the longitudinal axis of the light guide bundle or tilted relative to this axis. The control device 9 provides corresponding control of the rotation or tilt.

[0036] Fig. Figure 3 shows a top view of the light coupling surface 5 of the light guide bundle made of Fig. 2. The light coupling surface is superimposed with the corresponding positions of LEDs 701 to 704. As can be seen from Fig. As can be seen from Figure 3, the coupling surface has a cylindrical cross-section, within which a multitude of optical fibers or light guides 8 are located, which for the sake of clarity are only partially labelled with this reference symbol. The representation of the Fig. Figure 3 is schematic, and a typical optical fiber bundle contains a significantly larger number of optical fibers. The diameter of the optical fiber bundle is, for example, around 6 mm. A typical diameter for an individual optical fiber is 0.8 mm.

[0037] The individual LEDs 701 to 704 are arranged on a common semiconductor chip and each forms a square emitting surface. LED 701 emits red light, LED 702 green light, LED 703 blue light, and LED 704 white light. Optical fibers exist into which several LEDs of different colors shine, such as the middle optical fiber in the top row, the middle optical fiber in the bottom row, and the central optical fiber in the middle. In this way, color mixtures of different colors can be generated in certain optical fibers, resulting in very attractive visual effects at opposite ends of the optical fibers in the vehicle's interior. In contrast, according to... Fig. 3. Optical fibers, into which only the light of an LED is partially or completely shone. In these optical fibers, the corresponding primary color of the LED shines very intensely.

[0038] In the embodiment of the Fig. 3. By arranging the LEDs, combinations of the colors red-green, red-blue, green-white, and white-blue can be formed in those light guides that are superimposed by the corresponding LEDs. Furthermore, all four colors—red, blue, green, and white—are combined in the central light guide. Nevertheless, the LEDs can also be arranged in a different order, and other colors can potentially be emitted by the LEDs.

[0039] Depending on the design, the control unit 9 can consist of Fig. 2. The LEDs of the individual light guide bundles can be controlled differently. In one variant, the control unit can control the brightness of the individual LEDs of all light guide bundles based on predetermined patterns, which are linked, for example, to specific events such as the opening or closing of vehicle doors. The generation of the patterns can also depend on signals from corresponding sensors in the vehicle, such as vehicle acceleration sensors, vehicle speed sensors, temperature sensors, or acoustic sensors. For example, if a sensor detects that the vehicle is moving, a wave-like movement of light from front to back can be generated based on the light points 2. Fig. 1. can be generated by appropriately controlling the LEDs.

[0040] In a particularly preferred embodiment, it is also possible for a vehicle occupant to adjust the control unit and thus the LEDs according to their own preferences. For this purpose, a user interface is provided, which in a preferred variant is integrated into a mobile device, such as a mobile phone or a tablet computer. Depending on the design of the user interface, the occupant can appropriately control the brightness or color of the individual light points according to their wishes, or, if necessary, activate corresponding programs for generating time-changing color patterns.

[0041] The embodiments of the invention described above offer a number of advantages. In particular, impressive multicolored lighting effects can be easily generated in the interior of a motor vehicle by means of a multitude of light points, which represent the ends of optical fibers. The invention is not limited to lighting in a headliner, but can also be used in other areas of the vehicle interior, such as the side panels. By means of suitable control of the LEDs, various types of lighting effects can be generated, and it is also possible for an occupant to operate the control unit themselves and thus adjust or configure the interior lighting according to their needs. Reference symbol list 1. Headliner 2 ends of optical fibers 3 fiber optic bundles 4 plug head 5 Light coupling area 6 sockets 701, 702, 703, 704 LEDs 8 optical fibers 9 Control unit I Vehicle interior

Claims

[1] Device for interior lighting of a motor vehicle, comprising one or more light guide bundles (3) made up of a plurality of light guides (8), wherein first ends of the light guides (8) of a respective light guide bundle (3) are combined to form a light coupling surface (5) and light coupled at the light coupling surface (5) is coupled out at second ends (2) of the light guides (8) opposite the first ends in order to illuminate the interior (I) of the motor vehicle, wherein the second ends (2) of the light guides (8) are positioned in an interior trim panel (1) for the motor vehicle such that each second end (2) when light exits there forms a light point on the interior trim panel (1) which illuminates the interior, characterized by, that a plurality of light sources (701, 702, 703, 704) with different emission colors are provided at the light coupling surface (5) of a respective light guide bundle (3), which can be controlled by means of a control device (9), wherein the light sources (701, 702, 703, 704) are arranged such that they emit light into different areas of the light coupling surface (5) during operation. [2] Device according to claim 1, characterized by , that the second ends (2) of the light guides (8) are positioned in a roof lining. [3] Device according to claim 1 or 2, characterized by , that the second ends of the light guides (8) of a respective light guide bundle (3) are distributed in the interior lining (1) and are preferably distributed unevenly. [4] Device according to any one of the preceding claims, characterized by, that the light sources (701, 702, 703, 704) comprise LEDs and in particular each light source (701, 702, 703, 704) of the plurality of light sources (701, 702, 703, 704) is an LED. [5] Device according to any one of the preceding claims, characterized by , that the light sources (701, 702, 703, 704) are arranged on the light coupling surface (5) such that at least a part of the light guides (8) on the light coupling surface (5) receives light from several light sources (701, 702, 703, 704). [6] Device according to any one of the preceding claims, characterized by , that the majority of light sources (701, 702, 703, 704) include at least one light source (701) with red emission color and / or at least one light source (702) with green emission color and / or at least one light source (703) with blue emission color and / or at least one light source with white emission color. [7] Device according to any one of the preceding claims, characterized by , that the majority of light sources (701, 702, 703, 704) consist of four light sources (701, 702, 703, 704) with red, green, blue and white emission colors. [8] Device according to claim 7, characterized by , that the four light sources (701, 702, 703, 704) are arranged such that two pairs of light sources (701, 702, 703, 704) are arranged offset from each other in a first direction along the light coupling surface (5), wherein the light sources (701, 702, 703, 704) of each pair are arranged next to each other in a second direction along the light coupling surface (5), which is perpendicular to the first direction. [9] Device according to any one of the preceding claims, characterized by, that between the light coupling surface (5) and the plurality of light sources (701, 702, 703, 704) one or more optical elements are arranged, in particular one or more diffusers and / or one or more optical filters and / or one or more prisms and / or one or more optical elements with a prismatic surface and / or one or more optical elements, each of which has areas with different light transmittances. [10] Device according to claim 9, characterized by , that one or more of the optical elements can be moved and / or rotated by means of the control device (9), in particular along or about an axis perpendicular to the light coupling surface (5). [11] Device according to any one of the preceding claims, characterized by , that the distance between the light coupling surface (5) and the plurality of light sources (701, 702, 703, 704) can be varied by means of the control device (9). [12] Device according to any one of the preceding claims, characterized by , that the brightness of the light sources (701, 702, 703, 704) of a respective light guide bundle (3) can be varied by means of the control device (9), wherein preferably the brightness of each light source (701, 702, 703, 704) can be adjusted independently of the other light sources (701, 702, 703, 704) of a respective light guide bundle (3) and / or wherein preferably the plurality of light sources (701, 702, 703, 704) of each light guide bundle (3) can be adjusted independently of the other light guide bundles (3). [13] Device according to claim 12, characterized by, that the control unit (9) controls the brightness of the light sources (701, 702, 703, 704) of a respective light guide bundle (701, 702, 703, 704) depending on the signals of one or more sensors in the vehicle, in particular depending on one or more vehicle acceleration sensors and / or vehicle speed sensors and / or temperature sensors and / or acoustic sensors. [14] Device according to any of the preceding claims, characterized by that the control unit (9) can be operated via a user interface, wherein the user interface is in particular integrated into a mobile device that communicates wirelessly with the control unit (9), or is permanently installed in the vehicle [15] Device according to any one of the preceding claims, characterized by, that the second ends (2) of the optical fibers (8) of a respective optical fiber bundle (5) are at least partially arranged at positions spaced apart from each other. [16] Motor vehicle comprising one or more devices according to any of the preceding claims.

Images