CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a U.S. National Phase Application Under 35 U.S.C. § 371 of International Application No. PCT/EP2018/071834, filed Aug. 10, 2018, entitled “LIGHTING DEVICE FOR A VEHICLE, IN PARTICULAR AN ELECTRIC VEHICLE,” which claims the benefit of priority of German Patent Application No. 102017120532.2, filed on Sep. 6, 2017.

FIELD

The present disclosure relates to a lighting device, in particular for integration into a vehicle surface.

BACKGROUND

Motor vehicle lights, such as taillights, in which light-emitting diodes, rather than incandescent lamps, function as illuminants, are known from the prior art. As examples, refer to DE 33 15 785 A1, DE 39 16 875 A1, and DE 42 28 895 A1, which relate to motor vehicle lights or signal lights in which light-emitting diodes are used as illuminants. The known luminous devices are designed according to the requirements of known signal functions of road vehicles.

For example, DE 39 16 875 A1 discloses a signal light that has several functional fields, each functional field being assigned to a specific signal function, such as direction-of-travel indicator, brakes, or tail light. It is desirable in the known lights that the function of the surfaces of the individual functional fields that are visible from the outside are perceptible due to reflected light, and that an adequate warning function is ensured thereby even when the illuminant is switched off, especially at night.

The use is known of accordingly configured headlights and taillights, which are typically present on a vehicle, —for implementing additional signal functions that go beyond the functions required by regulations, for example, the so-called coming-home function or the leaving-home function. For present-day and future vehicles, there currently exists an additional need to implement non-standard signal functions, for example, signaling an autonomous driving mode of the vehicle.

Further exemplary known lighting devices are disclosed in DE 100 21 114 A1, DE 10 2014 110 084 A1, DE 10 2016 123 877 A1, DE 202 16 948 U1, WO 2017/121 516 A1.

SUMMARY

It is an object of the present disclosure to provide a lighting device that can be easily integrated into the design of surface areas of a vehicle, that is simple to manufacture, and that can display various signal functions during use, and that in the switched-off state integrates as inconspicuously as possible into the overall appearance of the vehicle.

This object is achieved by a lighting device having the features of the independent claim1.

Further features and details of the disclosure can be gathered from the description and the drawings. Particular embodiments of the lighting device are provided in the dependent claims. It should be noted that the features listed individually in the patent claims may be combined with one another in any technologically reasonable manner and disclose further embodiments of the disclosure. The description, in particular in connection with the figures, further characterizes and specifies the disclosure.

A central idea of the present disclosure is to make surface areas of a vehicle accessible to use for signal functions during the course of the integration of light sources, which may be done without loss of space. Accordingly, the device of the disclosure has a very low installation depth and permits the use of materials that are soft in comparison with conventional vehicle body materials, so that, as far as the protection of pedestrians in the event of an impact is concerned, no space for crumple zones or the like is lost apart from the necessary installation depth. In a particular embodiment, the lighting device according to the disclosure is at least partially integrated into a bumper of a vehicle, for example, and is thus a hybrid device consisting of a bumper and a lighting device.

A first aspect of the present disclosure provides a lighting device, particularly for integration into a vehicle surface. The lighting device according to the disclosure includes the following: a cover with optically opaque surface areas, an illuminant carrier arranged behind the cover and having a plurality of light sources, which may be point light sources, and signal structures, arranged between adjacent surface areas, which can be illuminated, in particular, illuminated from the rear, in order to emit light. According to the disclosure, this arrangement can be used to set different signal patterns by means of selective control of certain of the light sources by trans-illuminating or illuminating one or more associated signal structures.

“Optically opaque” in this context means that such a surface area does not emit any light at its surface to the outside when illuminated from the rear side of the cover. This can be achieved in a conventional manner, for example, by a corresponding opaque or light-impermeable surface coating. For example, the cover in the opaque surface areas may be painted with the same paint as the rest of the vehicle body. Alternatively, the optically opaque surface regions may also be coated with surface coating materials that are different from the rest of the vehicle paint job, for example, metallized by vapor deposition, coated with a metal film or alternatively also with a general optically opaque film. The illuminant carrier may be constructed essentially similarly to a circuit board on which a plurality of light sources, which may be point light sources, such as light-emitting diodes, are arranged in a matrix or restricted to specific areas and are wired for electrical control and power supply. A matrix of light sources is particularly suited for maximum flexibility with regard to the design of the signal structures. Alternatively, light sources may be arranged on the illuminant carrier only at such locations as are located directly behind a signal structure arranged in or on the cover.

An inventive signal structure forms part of the cover and may be integrated into the cover. A signal structure may be formed by a light-transmissive structure raised above the adjacent optically opaque surface areas. Alternatively, or additionally, a signal structure may also be a light-transmissive structure terminating flush with the adjacent optically opaque surface areas.

Alternatively, or additionally, a signal structure may also be a light-transmissive structure, forming a depression between the adjacent optically opaque surface areas. In other words, a particular signal structure may be formed in or on the cover by a single one of the measures discussed above or any combination of the measures mentioned above.

In an embodiment, the cover essentially consists of a transparent material, such as a transparent plastic, such as Plexiglas, that is integrated into the desired signal structures.

The optically opaque surface areas defined by the signal structures on the cover may be implemented by the measures already discussed above.

A signal structure in the cover may be implemented as a transparent area, or at least a translucent area when compared with the optically opaque surface areas. Alternatively, or additionally, a signal structure may also be implemented in the cover as a colored and translucent area. For the latter case, it is sufficient if the light sources of the illuminant carrier provided for illuminating the associated signal structure emit white light, since desired color effects are already predetermined by the color of the signal structure. In a particular embodiment, the signal structures are designed to be transparent and the associated light sources can be controlled with respect to the light color or can be light sources with white light.

The lighting device according to the disclosure may be operatively and communicatively connected to a control device for selecting and accordingly controlling the desired signal function. The control device may be programmed to control the light sources required for a particular signal structure so that the thus selected signal structure is illuminated as desired for light output corresponding to the desired signal function.

A signal function can be achieved by uniformly activating associated light sources, i.e., such light sources as are configured for illuminating an associated signal structure. Likewise, individual light sources may be activated at different strengths simultaneously and/or in a predetermined activation order. It is also possible to activate only a certain subset of the light sources associated with the illumination of a specific signal structure.

In addition, a luminous strip or luminous edge may be formed around the individual surface areas or may be completely or partially around the entire cover in the outer portion or edge portion, by accordingly controlling the light sources that are located there.

In a further development, the lighting device may additionally have an additional luminous edge on the periphery (in addition to the illuminant carrier), which may form at least a part or parts in the manner of a frame for the lighting device. The luminous edge may be made, for example, of a diffuse and thus non-transparent material that scatters light. The luminous edge may thus be illuminated by means of a series of light sources arranged behind it. By corresponding activation of the light sources, additional signal effects can thus be generated by the luminous edge.

As said above, the light sources may be point light sources, which may be implemented by means of light-emitting diodes (LEDs), for example by means of organic LEDs (OLEDs). The (O)LEDs may be designed for the generation of RGB colors so that the color of each point light source may be adjusted by a corresponding control. Using light sources that are designed only for white light is also possible, as is a mixed use of RGB light sources and white light sources.

At least some of the light sources, in particular the light sources associated with the specific signal structures, may be additionally provided with a diffuser or light-scattering optical devices and/or with a reflector. By using one or both of these measures, the luminance as well as uniformity of the light distribution in the signal structures can be improved.

In the lighting device according to the disclosure, a light-scattering diffuser layer may additionally be arranged between the cover and the illuminant carrier. In a manner similar to that described above with reference to particular embodiments of the light sources, a diffuser layer may be more favorable, especially in the embodiment of the illuminant support as a light-source matrix, rather than providing a diffuser or a light-scattering optical device on each light source.

In connection with the embodiment of the illuminant carrier as a light source matrix, the cover, and thus the signal structures integrated in the cover, may be designed to be exchangeable. As a result, the lighting device can be adapted relatively quickly to new requirements with minimal effort, or components that are essentially identical with the exception of the cover may be used for different models.

A second aspect of the present disclosure relates to a vehicle, in particular an electric vehicle, having a lighting device according to the first aspect of the disclosure. In the vehicle, at least one control device is provided for controlling the lighting device, especially the light sources arranged therein. The control device is configured to control the light sources in accordance with a desired signal function, so that certain signal structures can be selectively illuminated for light output in order to carry out the desired signal function.

The control device may in particular be configured to control certain signal functions only during operation of the vehicle or only during standstill of the vehicle. Of course, there may also be signal functions that are useful both during operation of the vehicle and during a standstill.

A further aspect of the present disclosure relates to a method for adjusting various signal functions of a lighting device according to the first aspect of the present disclosure, in particular in a vehicle according to the second aspect of the disclosure. The method includes the following steps: selecting a particular signal function; and controlling light sources associated with the selected signal function in order to illuminate from the rear the signal structure or signal structures arranged in front of it in order to emit light.

The lighting device may be activated by means of the method to implement certain signal functions, a signal function being at least one of the group consisting of, but not limited to: coming-home function, leaving-home function, welcome function, daytime running light (DLR light), driving mode indicator of the vehicle, such as autonomous driving, charge state indicator for a drive battery in an electric vehicle, signaling on a surface of a vehicle operations taking place in an area covered by the vehicle, and signaling of available parking space in front of or behind the vehicle, to name but a few examples. A fourth aspect of the present disclosure relates to possible uses of the inventive lighting device of the first aspect of the present disclosure, in particular for implementation on a vehicle, particularly an electric vehicle, wherein the signal functions to be implemented are those described above in connection with the method according to the third aspect of the disclosure.

The disclosure is particularly suited for vehicles, such as motor vehicles, for example electric vehicles, in which a luminous or display surface is to be back-lit or trans-illuminated in various ways. For this purpose, particularly suitable areas are located in the area of the front and rear of a vehicle, and particularly in the area of the headlights and tail lights which are usually provided for road vehicles, for example in the area between these lights.

