WO2008076612A1

WO2008076612A1 - System for illuminating a license plate

Info

Publication number: WO2008076612A1
Application number: PCT/US2007/086073
Authority: WO
Inventors: Arnold Eberwein
Original assignee: 3M Innovative Properties Company
Priority date: 2006-12-18
Filing date: 2007-11-30
Publication date: 2008-06-26
Also published as: GB0625167D0; TW200909256A; EP2102033A1

Abstract

The present invention provides a license plate illuminating system for a vehicle. The system comprises a first illumination device which at least partially overlaps the indicia area of the license plate, and an interface having an electrical connector for connecting a second illumination device. Further, a method of retrofitting a second illumination device is provided and a tool for retrofitting a second illumination device to the license plate illuminating system. The invention also provides a kit for illumination of a license plate of a vehicle and a vehicle comprising a license plate illuminating system according to the invention.

Description

SYSTEM FOR ILLUMINATING A LICENSE PLATE

The invention relates to an illuminating system for a license plate of a vehicle having a first illumination device and an electrical connector for connecting a second illumination device. The invention also concerns a second illumination device which is adapted to cooperate with the license plate illuminating system. Furthermore the invention is related to a kit comprising a license plate illuminating system and a second illumination device as well as to a method of retrofitting a second illumination device with a license plate illuminating system and a tool therefor.

Commonly license plates for motor vehicles such as cars, busses and trucks and for trailers, typically can be illuminated from their front face by lights arranged on the vehicles. The license plates typically have indicia which thereby are made visible under conditions of low illumination such as ambient darkness or inside a poorly lit parking garage. Usually such indicia represent, for example, the license plate number issued by the appropriate national authorities. Typically, the lights for illumination of a license plate are arranged aside of the license plate so that its front face is not obscured by the lights and the license plate is visible from its front. Such an arrangement has the disadvantage of limiting the design possibilities of car manufacturers. In particular, the lights that need to be arranged along one or more sides of the license plate hinder the car manufacturers in making more appealing designs because the lights often appear as a disturbing element in the design. Furthermore, such front-illuminated license plates may generally be illuminated non-uniformly so that recognition in the dark may be difficult, particularly under bad weather conditions such as rainfall.

In the recent years a variety of solutions for alternative illumination of license plates of vehicles have been disclosed or provided. In particular, a recent development relates to the use of so-called backlit or internally illuminated license plates. Such license plates may include an electroluminescent layer as for example disclosed in WO 03/062014 Al. A further example of an internally illuminated license plate is disclosed in WO 2004/101321. This license plate has a retro-reflective film and indicia in front of a light guide for more homogeneous illumination.

WO 2005/102783 Al discloses a license plate assembly with a light source for back illumination of the license plate.

Another example related to license plate illumination is DE 102 40 663 Al which describes a holder with an integrated lighting for a license plate. The lighting is provided by LEDs that are arranged aside an area on which the license plate can be placed.

Although these recently developed internally illuminated license plates offer a number of advantages, their wider spread and introduction is hampered because the market acceptance in the license plate field does not only depend on the technical solutions that are available and associated advantages, but also on regulatory requirements imposed by national authorities. As a result, the newly developed license plate may be permitted in one country but not yet in another country. One of the advantages associated with internally illuminated license plates is that these plates offer more options for the design of cars. To take full advantage of this would require that the newly internally illuminated license plates be allowed essentially world-wide as the car manufacturer would otherwise have to have different car designs for different countries depending on whether or not internally illuminated license plates are permitted in a relevant country or not.

Accordingly, the introduction of the internally illuminated license plates has been limited so far to replacing a conventional plate with the new plate in countries where the plates are now permitted such as in Germany. While this takes advantage of the improved visibility of the plates, it still does not take advantage of the design freedom created by the new license plates.

It would therefore be desirable to find a solution that allows taking full advantage of the benefits of an internally illuminated license plate, in particular in the car design, while taking into account the complexity that is created by different regulatory requirements existing world wide. It is further desirable that this solution be easy and convenient without increasing or at least not substantially increasing the cost of the license plate system on motor vehicles. Preferably the license plate system would also be one that does not require a high power consumption and which would otherwise increase fuel consumption of the motor vehicle.

A first aspect of the invention is related to a license plate illuminating system for a vehicle. The system comprises a first illumination device which at least partially overlaps the indicia area of the license plate. The system further comprises an interface having an electrical connector for connecting a second illumination device.

In this regard the term "overlap" is related to a position of at least a part of the first illumination device perpendicularly in front or behind of the indicia area of the license plate. In other words a perpendicular projection of the first illumination device onto the plane of the indicia area would at least partially lie within the indicia area. Typically, the first illumination device will fully overlap the indicia area or at least the indicia.

The indicia typically represent the licensed number of the license plate, and may also represent a country logo, state or county logo, and graphics such as flags, emblems and/or crests. The indicia area includes the area defined by the licensed number and preferably the indicia area further includes peripheral areas bearing country specific information such as logos, graphics, emblems and/or crests.

The invention may provide one or more of the following advantages. While one of the illumination devices can be designed for operating with an internally illuminated license plate (for example a back illuminated license plate), the second illumination device can be retrofitted or connected to the license plate illuminating system so that a conventional license plate can be illuminated in a conventional way therewith in countries that do not

(yet) permit the internally illuminated license plate. Hence, a car manufacturer only has to design one model of such license plate illuminating system and still be able to sell that model independent of the requirements in the various countries that may be imposed on the license plate illuminating system. The independence of country requirements may also help accelerating market penetration because it is also possible to sell into markets that are not yet prepared for a new license plate illuminating system. Additionally, the hurdle for a country to change to the new system may be reduced by making the new system available first. A further advantage of the invention may include the fact that the same power source can be used in connection with both illumination devices thereby minimizing power consumption of the system. Typically the system allows an easy and rapid retrofitting the second illumination device to the license plate illuminating system and therefore an easy and rapid conversion from one illumination device on the other. For example, such retrofitting could be carried out by a purchaser of a car or by the dealership. Further, such retrofitting could be carried out, for example, by the dealership and the purchaser of a car may change to the new system himself at any time his country grants permission.

The invention further allows vehicles to be supplied with two license plate illumination devices by the car manufacturer so that the purchaser of the car may save costs for retrofitting a second illumination device by a dealer or workshop.

Preferably the interface enables connecting of a second illumination device with the first illumination device remaining in its intended position in the license plate illuminating system.

In a preferred embodiment of the invention, the electrical connector comprises a power source for the second illumination device. Preferably the power source is adapted to power the second illumination device, and more preferably it is adapted to power the light source or light sources of the second illumination device. The power source for the second illumination device preferably provides voltage below 50 V, preferably a voltage of between 5 and 28 V and more preferably a voltage of between 10 and 14V.

The electrical connector is preferably a part of a plug and socket connector adapted to cooperate with a corresponding other part of a connector at the second illumination device. Further, connectors comprising flat contacts may be used, for example as available from MagCode AG in Heidenheim, Germany. In a further embodiment of the invention, the license plate illuminating system is adapted to detect electrical connection of the second illumination device. Electrical connection of the second illumination device may be detected by recognizing a current flow via the electrical connector. The license plate illuminating system may also comprise a switch which is automatically activated upon electrical or mechanical connection of the second illumination device. Such switch may be, for example a mechanical switch which is integrated in a socket and may be mechanically activated by the plug when it is pushed into the socket. Alternatively, the connection of the second illumination device may close or open an electric circuit. The change of the status of the electric circuit may be detected. For example, the electrical connector may comprise two contacts which are shorted upon connecting the second illumination device and such shortage may be detected, for example by an electronic circuit.

In a preferred embodiment of the invention, detection of connection of the second illumination device is evaluated to trigger the operation of the first illumination device. Preferably the first illumination device is switched off upon connection of the second illumination device. Thereby it is possible to disable the first illumination device upon connecting the second illumination device, hence to switch from the first to the second illumination device.

In another embodiment of the invention, the interface comprises a mechanical connector for attaching the second illumination device to the system. The mechanical connector may also comprise a mechanical connector for attaching a frame for holding the license plate to the license plate illuminating system. Preferably the mechanical connector provides for removable attachment of the second illumination device and/or frame to the license plate illuminating system. The mechanical connector may be part of a housing of the license plate illuminating system to which the frame may be attached. The housing may be adapted to hold further parts of the system, like the first illumination device and a light guide. Alternatively, or additionally, the mechanical connector may be part of the frame for holding the license plate. The mechanical connector may comprise one part of a locking mechanism which is adapted to co-operate, for example interlock, with another part of the locking mechanism at the second illumination device and/or frame. Such part of a locking mechanism may be a hook or other retaining member with a retaining element that allows for interlocking with another similar part, an edge or other suitable structure. The locking mechanism preferably provides for tool-less locking, and preferably requires a tool for unlocking.

Further, the mechanical connector may comprise a feature for aligning the frame, for example one or more pins or guiding members, which help to assemble the frame in the desired position. Preferably the parts of the locking mechanism additionally provide such alignment function. For example, the frame may comprise a plurality of retaining members arranged around the frame which may be mated with co-operating structures of the housing of the license plate illuminating system in a non-interlocked state. Once the retaining members are mated with the structures at the housing the frame by just pushing may be snapped on the housing.

In one embodiment of the invention the system comprises a license plate. Further the system may also comprise the frame for holding the license plate. Preferentially, the license plate is light transmissive.

In another embodiment of the invention, the license plate is opaque and covers the first illumination device at least partially. Preferably, such opaque license plate substantially completely covers the first illumination device. Thereby it may be possible to disable the first illumination device without switching it off.

The license plate of any embodiment may comprise a retro-reflective area, for example to reflect at least a part of the light that impinges on the front of the license plate when the license plate is illuminated by an external light source such as a headlight from another car. Typically the front of the license plate is the side that represents the indicia to a viewer. In a preferred embodiment of the invention the first illumination device is adapted for back illumination of the license plate. In this regard back illumination means that the license plate is illuminated from any position opposite of the front of the license plate. In other words the license plate in this case is arranged between the first illumination device and a potential viewer.

In a preferred embodiment of the invention the first illumination device comprises a light dispersion member. Such light dispersion member is preferably a passive device which is generally adapted to distribute the light of a light source onto a surface. Preferably the light dispersion member comprises a light guide. Such an illumination device offers the advantage that it can operate with the typical low voltage used in cars and other motor vehicles. It further offers the advantage that the second illumination device can use the same power source as the first illumination device and further minimizes the need for complicated and expensive electronic circuitry.

In a preferred embodiment the light guide is a generally flat body with major front and back faces. Preferably the front and back faces have a size generally corresponding to the format of least the indicia area of the license plate, and more preferably a size generally corresponding to at least the format of the license plate. Preferably such light guide is illuminated from a side face. The light is preferably scattered within the light guide, for example by particles, so that the light guide emits the light substantially in all directions. Preferably the light guide emits a part of the light substantially homogeneously at least through the major front face.

Preferably the light source for illuminating of the light guide comprises a LED (Light Emitting Diode), preferably a plurality of LEDs. The light source for illuminating of the light guide may also comprise a light bulb or a plurality of light bulbs. Further, the light source may comprise one or more linear light sources, such as an electric discharge lamp, for example a neon lamp. Different light sources may also be combined.

In another embodiment of the invention the first illumination device comprises a surface emitter. The surface emitter is preferably an active device, for example in the form of a panel or sheet, wherein the light is generated spread over a surface. The surface emitter may be an OLED (Organic Light Emitting Diode) or an inorganic electroluminescent light source.

In another preferred embodiment of the invention the license plate illuminating system is part of a vehicle. The system may be a pre-finished unit which is attachable to the vehicle. Further, at least some of the components of the system may be integrated parts of the vehicle. For example the first illumination device, the light guide and the interface may be integrated parts of the vehicle.

In a second aspect the invention relates to an illumination device for illuminating a license plate of a vehicle as it may be used as second illumination device in combination with the license plate illuminating system according to the invention. For better clarity the illumination device of the second aspect of the invention is further referred to as the second illumination device. The second illumination device is adapted to co-operate with a license plate illuminating system comprising a first illumination device as described above. Preferably the second illumination device has an interface for co-operation with the interface of the license plate illuminating system of the invention. For example, the second illumination device may have an electrical connector that can be mated and electrically connected with the electrical connector of the system according to the invention. Further the second illumination device may have a mechanical connector that can be mated with the mechanical connector of the system according to the invention.

In one embodiment, the second illumination device is adapted for front illumination of the license plate. Typically, the second illumination device is adapted for assembly at the license plate illuminating system (having the first illumination device) without overlapping the indicia area of the license plate, for example at one or more of the peripheral edges of the license plate. Typically, the second illumination device may be arranged to illuminate the license plate from the front (front illumination) whereby the light emitted by the second illumination device impinges the plane defined by the indicia area at an angle different than a perpendicular on that plane and whereby the light source of the second illumination device is some distance away from the front of the license plate. Preferably the second illumination device is adapted for assembly at the license plate illuminating system at the peripheral edge of the indicia area of the license plate and whereby the light source included in the second illumination device is arranged so as to have light thereof impinge on the front of the license plate.

In another embodiment, the second illumination device comprises a frame for holding the license plate. Preferably, the frame is adapted to be fitted with the license plate illuminating system having the first illumination device. The frame may comprise a part of a locking mechanism which is adapted for co-operation with another part of the locking mechanism of the license plate illuminating system.

In a third aspect the invention relates to a kit, comprising a system and a second illumination device according to the invention. Preferably the kit comprises a tool for demounting and/or assembling of the second illumination device with the license plate illuminating system according to the invention. The kit may further comprise instructions for use of the license plate illuminating system, the second illumination device, and/or mounting instructions to fit the second illumination device to the license plate illuminating system.

In a fourth aspect, the invention is directed to a method of retrofitting a second illumination device with a license plate illuminating system that has a first illumination device, comprising the steps of (i) positioning the second illumination device relative to the license plate illuminating system; and (ii) mounting the second illumination device with the license plate illuminating system, such that the second illumination device connects with the electrical connector of the interface.

Preferably retrofitting of the second illumination device automatically switches off the first illumination device. Retrofitting of the second illumination device may be a tool-less method, for example the second illumination device may be manually attached to the system, preferably also without prior disassembly of parts. In a fifth aspect the invention relates to a kit for illumination of a license plate of a vehicle, adapted to be selectively used with an opaque license plate or a light transmissive license plate, the kit comprising - a first illumination device for back illumination of the license plate, and a first and a second frame for holding the license plate, the first and second frames being interchangeable, wherein the second frame comprises an illumination device for front lighting of the license plate. Such kit may further comprise the license plate or materials for making a license plate.

In a sixth aspect the invention relates to a vehicle comprising a system according to the invention.

Brief Description of the Drawings

Fig. Ia shows a perspective view of a system for illuminating a license plate with a license plate and a frame for holding the license plate according to an embodiment of the invention; Fig. Ib shows a perspective view of a system for illuminating a license plate with a license plate and a frame having a second illumination device according to an embodiment of the invention; Fig. 2 shows a perspective view of a system according an embodiment of the invention; Fig. 3 shows a perspective view of a license plate according to an embodiment of the invention; Fig. 4 shows a perspective view of a system with second illumination devices according to an embodiment of the invention;

Fig. 5a, 5b show perspective views of the second illumination device of Fig. 4 according to an embodiment of the invention;

Fig. 6 shows a perspective view of a system with another embodiment of a second illumination device according to an embodiment of the invention; Fig. 7 shows a perspective view of the second illumination device of Fig. 6 according to an embodiment of the invention; Fig. 8a is a schematic cross-sectional view of a system for back illumination of a license plate according to an embodiment of the invention; Fig. 8b is a schematic cross-sectional view of the system of Fig. 8a combined with a frame for front illumination of a license plate according to an embodiment of the invention; Fig. 9a, 9b show schematic views of a switch for switching between the first and second illumination devices according to an embodiment of the invention;

Fig. 10 is a schematic partial view of a vehicle comprising a license plate illuminating system according to an embodiment of the invention;

Detailed Description of the Invention Fig. Ia shows a housing 10, a license plate 20 and a frame 30 for holding the license plate 20. The frame 30 is interchangeable with frame 50. A configuration in which the frame 30 is replaced by a frame 50 is shown in Fig. Ib. The frame 50 has an integrated second illumination device 60. The housing as it is part of the license plate illuminating system as shown in Figures Ia and Ib has a first illumination device 15 which is adapted for back illumination of the license plate 20, in particular for surface back illumination of the license plate. The housing 10 has also an interface with electrical connectors 11. The electrical connectors are shown as two pairs of sockets each providing bipolar connection to the second illumination device 60. However, other configurations are possible, like for example only one bipolar connector or even one unipolar connector. In case a unipolar connector is provided the second illumination device may be connected to a second pole, for example the ground, separately. Furthermore the housing 10 comprises mechanical connectors 12 for retaining the second illumination device 60 and/or the frames 30 and 50. The frame 50 and the frame 30 may be retained at the housing by additional mechanical connectors (not shown). The frames 30 and 50 as well as the housing 10 may be made of a thermoplastic or thermosetting polymeric materials, preferably comprising acrylonitrile- butadiene-styrene (ABS), polycarbonate (PC), polyolefins, polyamides (PA), acrylics, or blends of these materials. In any case the materials may be selected to fulfill standards, for example regulatory standards and/or technical standards like the International Standard ISO "Road Vehicles" 7591 - 1982-12-01. Primary regulatory requirements for license plates and associated housings are related to low temperature impact resistance, stability at high temperature, robustness on exposure to rapid temperature changes as well as fuel resistance.

In Fig. 2 the housing 10 is shown with the size of an indicia area 25 of a license plate indicated in front of the first illumination device 15 by broken lines. As can be seen in this example, the first illumination device 15 has a larger area than the indicia area 25. Preferably, the format of the first illumination device 15 substantially corresponds to the format of a license plate, as for example shown in Fig. 3. Other formats however are possible.

Fig. 3 shows a license plate having an indicia area 25 and indicia 26. The license plate preferably has a light transmissive area 21 (in this example generally corresponding to the area outside the indicia) and less light transmissive or opaque areas 22 (in this example generally corresponding to the area of the indicia). The license plate may be made of a generally light transmissive material, and may be subsequently inked, for example at raised areas. For example the license plate may be made of a light transmissive plastic sheeting which may further have retro-reflective properties. Such retro-reflective properties may be provided by a prismatic or cube-cornered structure on the sheeting or on a layer of the sheeting, by glass beads, metal plated areas or areas printed with metal filled inks, for example. Indicia may be formed by several methods, including embossing license plates and then blackening (or coloring) the raised areas corresponding to indicia with ink or hot-stamping transfer films. Indica may also be provided by applying ink or transfer films to the license plate in the form of indicia without embossing the license plate. Adhesive-coated films in the form of indicia may also be adhered to the license plate. In the case of a transparent license plate, indica may be placed either on the front surface of the license plate or the rear surface. Alternatively, a clear sheet bearing indica may be placed directly in front of or behind the license plate, thus providing indicia that are not directly attached to the license plate. Fig. 4 shows a system with a frame 30a placed on the housing 10. The frame 30a has apertures 11a, 12a to provide access to the electrical connectors 11 and the mechanical connectors 12 in housing 10 through the frame 30a. As shown, the apertures 11a, 12a preferably have a shape similar to the shape of the connectors 11. The housing 10 again comprises a first illumination device 15 which provides for back illumination of a license plate (not shown). Second illumination devices 70 are illustrated in front of the frame 30a.

A second illumination device 70 as shown in Figs. 5a, 5b has an interface comprising electrical connectors 71 as well as mechanical connectors 72. Further the second illumination device 70 comprises a lamp 75 (shown in Fig. 5b), for example comprising a light bulb or an LED as light source. The lamp may comprise a transparent cover with structures for spreading the light. A mechanical connector 72 in the example shown is a mushroom shaped protrusion, and intended to be locked with the mechanical connector 12 of the housing which is basically a hole. The "mushroom head" of the connector 72 has a greater diameter than the hole. The connector 72 is crosswise slitted from the top or free end towards the bottom so that it can be compressed radially when it is inserted into the hole. The front most free end of the connector 72 comprises a chamfer which allows it to be easily inserted into the hole. The connector 72 has a length so that the mushroom head can be moved all the way through the hole and snap behind the wall around the hole. There may be a variety of other mechanical connectors like hooks, screws, tapered structures, for example, that might provide for a similar function as it is described for the locking mechanism formed by mechanical connectors 12, 72.

An electrical connector 71 as illustrated in the example of Fig. 5a and 5b is a pin having a generally rectangular cross-section, for example as it is used in the car industry quite commonly. However, other electrical connectors can be used like connectors comprising flat contacts. It may also be possible to provide a contactless coupling instead of an electric connection. This would help to prevent contact corrosion and easier mounting of the second illumination device.

The electrical connector may also comprise the mechanical connector. In other words the electrical connector and the mechanical connector may be combined. For example the electrical contacts may comprise a retaining member like a hook or mushroom head or the like.

Fig. 6 shows a combination of a system having a housing 10 and a frame 30a with an elongated second illumination device 80. Such second illumination device 80, as it is also shown in Fig. 7, may comprise an electric discharge lamp, a series of LEDs or light bulbs or any other suitable light source. The second illumination device 80 further comprises mechanical connectors 82 and electrical connectors 81 which are similar to the mechanical connectors 72 and electrical connectors 71 as described for Fig. 5. It can be seen that the type of locking mechanism formed by mechanical connectors 12 and 72, 82 provides for tool-less interlocking. Once the locking mechanism is in an interlocked status it can only conveniently be unlocked by use of a tool.

Fig. 8a and 8b show schematic cross-sectional side views of a system for illuminating a license plate. A housing 10 comprises a first illumination device 15. The first illumination device 15 comprises a light source 17 and a light guide 16. The light guide 16 is a generally flat panel having major front and back faces. The light guide has a size generally corresponding to the format of the license plate 20. The light guide 16 is illuminated from a side face by an array of LEDs 100. Other light sources may be used, like one or more light bulbs, or electric discharge lamps, for example. In the example shown the array of LEDs 100 is arranged at the bottom of the light guide directly in front of a side face of the light guide. A light source, like the array of LEDs, may however be arranged at other side faces of the light guide and also along more than one side face. For example, a light source may extend all around the light guide. Further, more than one light source may be used, for example one array of LEDs for each side face.

The light guide 16 comprises a first material having a first light refracting index and a second material having a second light refracting index, wherein the first and second light refracting indices are different from one another. The second material is preferably dispersed within the first material, for example in the form of particles. The first material guides light from the light source into the light guide. Light meeting the particles of the second material is scattered at the particles in generally all directions. Because the particles are preferably generally homogeneously distributed within the body of the light guide the light guide emits such scattered light generally homogeneously in all directions, and also through the major front face. Therefore the light guide can be used to generally homogeneously illuminate a surface.

In this example (Figs. 8a, 8b) the light guide 16 is arranged behind the license plate 20. Fig 8a shows the housing 10 with the first illumination device 15 combined with a license plate 20 and a frame 30 for holding the license plate 20. The first illumination device 15 is activated to generally homogeneously illuminate the license plate 20 from the back. In Fig. 8b the frame 30 is replaced by frame 50 which has a second illumination device 60 for front illumination of the license plate 20. Because of the electrical connection of the second illumination device 60 to the system (through electrical connectors 11, 71) the second illumination device 60 is activated and the first illumination device has been deactivated. As can be seen the license plate 20 is illuminated from an angle of the front face of the license plate. From Fig. 8b it can also be understood that in case the light transmissive license plate is replaced by an opaque license plate the first illumination device 15 becomes deactivated because the opaque license plate blocks the light. In that case the first illumination device 15 may remain electrically activated. A license plate for use with either of the configurations as shown in Figs. 8a and 8b may comprise a retro- reflective layer.

Fig. 9 shows schematically an electrical switch 90 as it may be used in an electrical connector, for example in electrical connectors 11 (Figs. Ia, Ib). Contact 92 is connected to a power source, for example to the electric system of a vehicle. Contact 93 is connected to the first illumination device and contact 91 belongs to the electric connector of the second illumination device (not shown). Fig. 9a shows the electrical switch with the second illumination device being disconnected from contact 92 so that the second illumination device is not powered. A current I may only flow along the path as illustrated by the dashed arrow because contacts 92 and 93 are connected with one another. Therefore the first illumination device may be powered. Fig. 9b shows the second illumination device being connected to contact 92 by contact 91. As illustrated, the contact 92 is lifted so that it is disconnected from contact 93. Therefore the first illumination device is disconnected from the power source upon contacting the second illumination device. Such switch function may also be provided by other mechanical switches or by electronic control. Optionally the switch may be provided by an encapsulated Reed switch. A Reed switch may, for example, be accommodated in the housing of the license plate illuminating system and a magnet for actuating the Reed switch may be provided in the second illumination device or the frame carrying the second illumination device.

Fig. 10 shows a vehicle 1000 comprising a license plate illuminating system. As shown the license plate illuminating system (including other components, like the license plate or the frame, for example) may be part of the vehicle 1000, for example fixed to it. Or components of the system, for example the housing and/or light source, may be integrated parts of the vehicle.

Claims

1. License plate illuminating system for a vehicle, comprising a first illumination device at least partially overlapping the indicia area of the license plate, and an interface having an electrical connector for connecting a second illumination device.

2. License plate illuminating system according claim 1, wherein the electrical connector comprises a power source for the second illumination device.

3. License plate illuminating system according to claim 2, wherein the power source for the second illumination device provides voltage below 50 V.

4. License plate illuminating system according to claim 3, wherein the power source for the second illumination device provides voltage between 5 and 26 V.

5. License plate illuminating system according to any of the preceding claims, being adapted to detect electrical connection of the second illumination device.

6. License plate illuminating system according to claim 5, wherein detection of connection of a second illumination device is evaluated to trigger operation of the first illumination device.

7. License plate illuminating system according to claim 6, wherein the first illumination device is switched off upon connection of a second illumination device.

8. License plate illuminating system according to any of the preceding claims, wherein the interface comprises a mechanical connector for mechanically attaching the second illumination device.

9. License plate illuminating system according to any of the preceding claims, further comprising a license plate.

10. License plate illuminating system according to claim 9, further comprising a frame for holding the license plate.

11. License plate illuminating system according to claims 9 or 10, wherein the license plate is light transmissive.

12. License plate illuminating system according to claim 9, wherein the license plate is opaque and covers the first illumination device at least partially.

13. License plate illuminating system according claims 9 to 12 wherein the license plate comprises a retro-reflective layer.

14. License plate illuminating system according to any of the claims 9 to 13, wherein the first illumination device is adapted for back illumination of the license plate.

15. License plate illuminating system according to any of the preceding claims, wherein the first illumination device comprises a light dispersion member.

16. License plate illuminating system according to claim any of the preceding claims, wherein the first illumination device comprises a light guide.

17. License plate illuminating system according to claim 16, wherein one of a plurality of LEDs, a plurality of light bulbs and an electric discharge lamp are used for illuminating the light guide.

18. License plate illuminating system according to any of the preceding claims, being part of a vehicle.

19. Illumination device for illuminating a license plate of a vehicle, adapted to co- operate with a license plate illuminating system according to claims 1 to 18.

20. Illumination device according to claim 19, having an interface for co-operation with the interface of the license plate illuminating system.

21. Illumination device according to claims 19 or 20, being adapted for front illumination of the license plate.

22. Illumination device according to claims 19, 20 or 21, being adapted for assembly at the license plate illuminating system at the peripheral edge of the indicia area of the license plate and whereby the light source included in the illumination device is arranged so as to have light thereof impinge on the front of the license plate.

23. Illumination device according to any of the claims 19 to 22, comprising a frame for holding the license plate.

24. Kit, comprising a license plate illuminating system according to claims 1 to 18 and an illumination device according to claims 19 to 23.

25. Kit according to claim 24, further comprising a tool for demounting and/or assembling of the second illumination device from/with the license plate illuminating system.

26. Kit of claim 24 or 25, further comprising mounting instructions to fit the second illumination device to the license plate illuminating system.

27. Tool for demounting and/or assembling of a second illumination device from/with the license plate illuminating system according to claims 1 to 18.

28. Method of retrofitting a second illumination device with a license plate illuminating system of claims 1 to 18, comprising the steps of: (i) positioning the second illumination device relative to the license plate illuminating system; and (ii) mounting the second illumination device with the license plate illuminating system, such that the second illumination device automatically connects with the electrical connector of the interface.

29. Method of claim 28, wherein retrofitting of the second illumination device automatically switches off the first illumination device.

30. Method of claim 28 or 29, wherein retrofitting of the second illumination device is a tool-less method.

31. Kit for illumination of a license plate of a vehicle, adapted to be selectively used with an opaque license plate or a light transmissive license plate, the kit comprising a first illumination device for back illumination of the license plate, and - a first and a second frame for holding the license plate, the first and second frames being interchangeable, wherein the second frame comprises an illumination device for front lighting of the license plate.

32. Kit of claim 31, further comprising a license plate or materials for making a license plate.

33. Vehicle comprising a license plate illuminating system according to claim 1 to 18.