Patent Description:
The term vehicle lighting and/or signalling device is used herein in a very broad sense so as to comprise a vehicle light, both rear and front, the latter also called a headlamp, or headlight.

This therefore comprises a sidelight, an indicator light, a brake light, a rear fog light, a reverse light, a dipped beam headlight, a main beam headlight and the like.

In addition, the term is also intended to a courtesy light, dashboard or part of it; therefore, the vehicle lighting and/or signalling device may be placed both internally and externally to the vehicle.

As is known, said vehicle lighting and/or signalling devices can be used both to illuminate and to send visual signals.

For these purposes, said devices comprise a plurality of lighting portions or faces having different colours and different levels of luminosity, (also according to the regulations to be complied with and) the like.

The need is increasingly felt to make vehicle lighting and/or signalling devices that ensure a high uniformity of the lighting portions in order to satisfy both aesthetic and functional requirements.

In this regard, solutions with O-LEDs exist in the art that guarantee a high uniformity of the lighting portions/faces; however, these solutions are very expensive and still have limitations in terms of realization of the lighting portions/faces adjacent to each other, which can in any case be activated independently.

Documents <CIT> and <CIT> disclose lighting and/or signalling devices with light guides separated by barrier elements.

Such latter limitation is not negligible given that the need is increasingly felt in the art to use the vehicle light not only as an instrument to satisfy type-approval requirements in order to obtain light beams that satisfy particular photometric requirements but also as a design instrument specific to the vehicle on which the light is used.

Therefore, the light pattern emitted by the light does not only have the function of fulfilling the signalling and/or lighting function but also that of creating a precise desired light effect.

In addition, the lighting and/or signalling device may also be used in order to send light signals such as texts, graphic symbols, as well as to produce light animations made by precise activation sequences of lighting portions.

Such need may be achieved by a lighting device comprising a segmented light guide, the segments of which may be switched on by command. Between two adjacent segments there is an opaque separation element, which prevents the light conveyed in one segment from passing into the adjacent segment. In order to have clear signals that are pleasant to look at, it is important to ensure that no light leaks, even minimal, are created between the various adjacent segments. However, some light beams may escape from the individual light guide elements and may be reflected by additional elements so as to enter, albeit in a minimal manner, adjacent segments. This problem of leakage occurs in particular at edges or perimeter boundary portions between adjacent segments and, moreover, the leakage may occur, by reflection, even between light guide segments not directly neighbouring or adjacent to each other.

The need is therefore felt in the art to provide a lighting and/or automotive signalling device that makes it possible to obtain the aforementioned technical effects, which guarantees a high homogeneity of lighting (comparable to that obtainable with the O-LEDs), but without presenting the drawbacks of the O-LED technology and that allow differentiated, exclusive and confined activation of specific portions of light, without light beam leakage phenomena.

In fact, any light leakage between adjacent lighting portions causes a worsening of the desired visual effect and a possible unclear communication of the information to be provided by activating single and clearly delineated portions.

In other words, the need is felt to provide an automotive headlight that has the same performance as O-led technology in terms of uniformity of lighting but significantly lower costs, as well as a light that has differentiated sectors that can be switched on separately without the risk of light leakage from one sector to another, i.e. without the risk that light rays can illuminate even partially a sector that does not need to be switched on.

Such need is satisfied by a vehicle lighting and/or signalling device according to claim <NUM>.

Other embodiments of the present invention are described in the dependent claims.

Further characteristics and advantages of the present invention will be more clearly comprehensible from the description given below of its preferred and non-limiting embodiments, wherein:.

The elements or parts of elements common to the embodiments described below will be indicated using the same reference numerals.

With reference to the aforementioned figures, reference numeral <NUM> globally denotes a vehicle light to which the following discussion will refer without by so doing detracting from its general application.

As mentioned above, the term lighting and/or signalling device is understood to mean indifferently a rear vehicle light or a front vehicle light, the latter also known as a headlight or headlamp, comprising an outside light of the vehicle having a lighting and/or signalling function, as for example a position light, which may be a front, back, side position light, a direction indicator light, a brake light, a rear fog light, a reversing light, a low beam headlight, a high beam headlight, and the like.

In addition, the term lighting and/or signalling device also means an interior courtesy light, a dashboard or part of it, a display and so forth.

Consequently, as better described below, in its signalling function the device may comprise the possibility of sending luminous signals, logos, but also written and luminous messages of any kind.

The lighting and/or signalling device <NUM> comprises a container body or housing <NUM>, usually of polymeric material, which generally allows the attachment of the lighting and/or signalling <NUM> device to the relative vehicle.

For the purposes of the present invention, the container body or housing <NUM> may be any shape, size and assume any position: for example, the container body <NUM> need not be directly associated to the body or other external fixtures of the associable vehicle.

As seen, the container body <NUM> may also be associated inside the vehicle, e.g. on the instrument panel, dashboard, parcel shelf and so forth.

The container body <NUM> delimits a containment seat <NUM> that houses a plurality of components of said lighting and/or signalling device and in particular LED light sources <NUM>.

The container body <NUM> may for example be associated, at least partially so as to close a lenticular body <NUM> so as to close said containment seat <NUM> housing at least one LED light source <NUM>.

For the purposes of the present invention the lenticular body <NUM> may be external to the vehicle lighting and or signalling device <NUM>, so as to define at least one outer wall of the vehicle lighting and or signalling device directly subject to the atmosphere.

The lenticular body <NUM> closes the containment seat <NUM> and is suitable to be crossed by the beam of light produced by the LED light source <NUM> which is transmitted to the outside of the containment seat <NUM>.

To such purpose, the lenticular body <NUM> is made of at least partially transparent or semi-transparent or translucent material, and may also comprise one or more opaque portions, so as to allow in any case the at least partial crossing of the light beam produced by the light source.

According to possible embodiments, the material of the lenticular body <NUM> is a resin such as PMMA, PC and the like.

A mask <NUM> may also be applied to the lenticular body <NUM> to appropriately delimit light emitting portions of the lighting and/or signalling device <NUM>, as further described below.

The lighting and/or signalling device <NUM> comprises at least two LED light sources <NUM>',<NUM>' ', powered and activated separately, each facing a respective light guide <NUM>' ,<NUM> ''.

The light guides <NUM> may have various shapes and conformations within the container body <NUM>.

The shapes and dimensions of the light guides <NUM>',<NUM>" may be various; the number of light guides may be greater than two and the light guides <NUM>', <NUM> " may be arranged to form lighting portions <NUM>,<NUM> having any shape and extension.

In this way it is possible to switch on different lighting portions, even in a large number (well beyond the two units) in order to create possible optical effects or also in order to create, with said lighting portions, the writing, logos, messages that may have additional functions compared to the established lighting function.

In this way the lighting device <NUM> becomes a signalling device. To this end, it is possible to form and arrange the light guides <NUM> so as to have lighting portions arranged according to various geometric patterns: in this way it is possible to compose alphanumeric codes that therefore comprise both numbers and letters of the alphabet.

The LED light sources <NUM>',<NUM>" each face a respective light input wall <NUM>' ,<NUM>" of the corresponding light guide <NUM>', <NUM>" through which the light beam produced is channelled inside the light guide <NUM>' ,<NUM> " and transmitted by the latter.

It is therefore evident that the LED light sources <NUM> can be placed at a margin of the respective light guides <NUM>.

The LED light sources <NUM>',<NUM>" are therefore arranged along a perimeter formed by the unification of the light guides <NUM>',<NUM>" and are powered /housed by an electronic board or several electronic boards <NUM> which follow said perimeter. The electronic boards <NUM> may be rigid or flexible in order to better adapt to said perimeter.

In particular, said light guides <NUM>',<NUM>' 'emit the light of said LED light sources <NUM>' ,<NUM> " through at least two respective and distinct lighting faces <NUM>,<NUM> at a front wall <NUM> of the lighting and/or signalling device <NUM>, said front wall <NUM> being permeable to light.

The light guides <NUM>',<NUM>" and the respective LED light sources <NUM>',<NUM>' are preferably configured to satisfy a total internal reflection condition of the light beam passing through said light guides <NUM>',<NUM>'.

In this case, the couplings between the light guides <NUM>',<NUM>" and the respective LED light sources <NUM>' ,<NUM> " are configured so that the light beam propagated inside said light guides <NUM> ',<NUM>' 'satisfies a total internal reflection condition between the opposite faces of the light guides <NUM>' ,<NUM> ", with respect to a prevailing propagation direction X-X and at the same time is diffused towards the margins of the aforementioned light guides according to a diffusion direction Y perpendicular to said prevailing propagation direction X.

As a result, the light input wall <NUM>',<NUM>" of the light guides <NUM>',<NUM>", directly facing the corresponding LED light sources <NUM>',<NUM>", is in turn configured to transmit the light inside the light guide <NUM>',<NUM>" in the total internal reflection condition.

The light input walls <NUM>',<NUM>' of the light guides <NUM> ',<NUM>' 'may comprise optics <NUM>, e.g., cylindrical section grooves or prominences, for opening the light beam along said Y-Y diffusion direction perpendicular to the prevailing X-X propagation direction.

Preferably, said optics <NUM> have a pitch between <NUM> and <NUM>.

The light guides <NUM>',<NUM>" are in turn provided with diffuser extractor elements <NUM> arranged on a rear wall <NUM> opposite the front wall <NUM>, and/or arranged on the front wall <NUM>, to extract the beam of light propagated inside said light guides <NUM>' ,<NUM> ".

In other words, the light beam produced by each light source <NUM>',<NUM>" penetrates inside the light guide <NUM>' ,<NUM> " through the light input wall <NUM> ',<NUM>' 'and is reflected inside the light guide <NUM>' ,<NUM> ", until it meets the diffuser extractor elements <NUM> that reflect it outside the light guide <NUM> ',<NUM>' '.

More precisely, the light beam diffused by the diffuser extractor elements <NUM>, located on the rear wall <NUM>, can be sent to the front wall <NUM> from which it exits.

However, the light beam diffused by the diffuser elements <NUM> may also be sent in the opposite direction, i.e., opposite the front wall <NUM>.

Each light guide <NUM>',<NUM>" is therefore provided with at least one reflector element <NUM>, associated with each light guide <NUM>' ,<NUM> " on the side of its rear wall <NUM>, so as to be directly facing the respective diffuser extractor elements <NUM>, to reintroduce the light that has come out of the light guide <NUM> ',<NUM>' 'and reflect it towards the front wall <NUM>.

The container body <NUM> may in turn be provided preferably with an inner side surface <NUM> provided with light reflecting elements <NUM>.

For example, the inner side surface <NUM> is reflective by means of a white film co-moulded along the inner side surface <NUM>.

As a result, the reflecting elements <NUM> are positioned rear of the diffuser extractor elements <NUM>.

According to a possible embodiment, the diffuser extractor elements <NUM> are micro-optics/micro structures, such as for example point-shaped micro-depressions, which diffuse light to the front wall <NUM> or towards the reflector element <NUM>.

Preferably, the diffuser extractor elements <NUM> are arranged according to a non-homogeneous scheme having a density that increases as the distance from the light source <NUM> increases along the extension of the light guide <NUM>',<NUM>".

According to a possible embodiment, the reflector element <NUM> is a white film reflecting the light coming from the rear wall <NUM> of the light guides <NUM>',<NUM>".

The reflector element <NUM> may also comprise a reflecting mirror.

According to the invention, said light guides <NUM>' ,<NUM>' are juxtaposed and adjacent to each other at at least one respective inner wall <NUM>.

In addition, the light guides <NUM>',<NUM>' are mechanically and optically separated by barrier elements <NUM> which prevent the passage of light between the light guides <NUM>',<NUM>" at said at least one inner wall <NUM>.

Preferably, said barrier elements <NUM> delimit the entire perimeter of the light guides <NUM>',<NUM>" so as to optically isolate and delimit the front wall <NUM> corresponding to each light guide <NUM>' ,<NUM> ".

According to the invention, said barrier elements <NUM> are separator septa opaque to the light extending from the reflector element <NUM> to at least said front wall <NUM>, crossing it completely.

According to the invention, said barrier elements <NUM> completely cross any portion transparent to light rays arranged beyond the reflector element <NUM> towards the front wall <NUM>, comprising the latter. In other words, said barrier elements <NUM> extend to encompass any surface capable of reflecting light rays coming out from the respective light guide segments.

According to a possible embodiment, said front wall <NUM> belongs to the light guide <NUM>.

According to a further possible embodiment, said front wall <NUM> belongs to the lenticular body <NUM> associated in front of said light guides <NUM>',<NUM>' ', on the opposite side with respect to the reflector element <NUM>. The lenticular body <NUM> is crossed by the barrier elements <NUM> that extend from the light guides <NUM>',<NUM>", so that the rays coming out from one of said light guides <NUM>' ,<NUM> " are not reflected by the front wall <NUM> towards the other light guide <NUM> " ,<NUM> '.

According to a possible embodiment, the barrier elements <NUM> are associated with the reflector element <NUM>, cross the light guide <NUM> and extend as far as the front wall <NUM>. The front wall <NUM> may moreover be a separate element from the lenticular body <NUM> and from the light guide <NUM> and be placed between these two elements.

According to a possible embodiment, said barrier elements <NUM> are co-moulded or embedded in the light guide <NUM> and extend at least partially (or even completely) inside the reflector element <NUM> and at least partially (or even completely) inside the front wall <NUM>.

An embodiment is also possible in which said barrier elements <NUM> are co-moulded with the front wall <NUM> and extend as far as the reflector element <NUM>. The barrier element <NUM> may also comprise a film opaque to light.

According to a further embodiment, a lenticular body <NUM> is provided, associated to cover the light guide <NUM>, wherein said lenticular body <NUM> is arranged at a distance from the light guide <NUM> such as not to be able to reflect back the light beams towards said light guide.

According to a possible embodiment, at least two light guides <NUM>',<NUM>' are provided, joined together by an appendage <NUM>, on the side of the respective light input walls <NUM>' ,<NUM> ", said appendage <NUM> being arranged in a position substantially rearward with respect to the LED light sources <NUM> ',<NUM>' ', parallel to a prevailing propagation direction X-X of the light beams emitted by the LED light sources <NUM>' ,<NUM> ". In this way the segmented light guide consists of a single piece to facilitate assembly.

For example, at least two appendages <NUM>',<NUM>" are provided connecting three light guides <NUM>' ,<NUM> " ,<NUM> " contiguous to each other, said appendages <NUM>' <NUM> " identifying a housing seat <NUM> of at least one light source <NUM>.

According to a possible embodiment, at least one of said separator septa or barrier elements <NUM> is provided with a through inner seat <NUM> inside which a perimeter light guide <NUM> is housed to which a perimeter light source <NUM> is associated configured to selectively illuminate said inner seat <NUM>.

Said inner seat <NUM> is optically shielded with respect to the adjacent light guides <NUM>',<NUM>' ', for example by opaque films.

All the lighting and/or signalling devices <NUM> described above, according to a possible embodiment, may comprise on the front wall <NUM>, at the lighting faces <NUM>,<NUM>, a diffuser e.g. opaline or embossed element <NUM>.

Said opaline or embossed diffuser element <NUM> may be applied in the form of films on the lighting faces <NUM>,<NUM>.

It is also possible to apply said opaline or embossed diffusion element <NUM> directly to the lenticular body <NUM>.

Said diffusion element <NUM> can thus be incorporated into the front wall <NUM> of the light guide <NUM> and/or into a lenticular body <NUM> associated to cover the light guide <NUM>.

The technical effect of such opaline or embossed, diffuser element <NUM> is to further homogenize the light beams emitted by the lighting faces of the lighting and/or signalling device in order to obtain a homogeneity of lighting completely equivalent to that obtainable with an O-led type technology.

It is therefore possible to create, for example, modules comprising two light guides <NUM>',<NUM>" with at least two respective lighting faces <NUM>,<NUM> and arrange them side by side so as to form complex lighting structures that can form particular light signals, symbols, logos, captions and messages of any kind.

Obviously, an appropriate activation sequence of the various lighting faces, thanks to the separate controls of the respective LED light sources, will make it possible to obtain specific graphic effects, written, but also animations of various types, according to the needs of the user.

As may be appreciated from the description, the present invention makes it possible to overcome the drawbacks mentioned of the prior art.

In particular, the automotive lighting and/or signalling device according to the present invention makes it possible to obtain any predefined luminous pattern provided with portions with any degree of luminance, capable of fulfilling all the photometric specifications of the headlight but also capable of emitting light signals, graphics of any type so as to become a communication tool of information as well as a light signalling and lighting device.

In addition, the lighting and/or signalling device according to the present invention allows any animation to be obtained by activation on command and according to a predetermined sequence of the lighting faces of the light guides.

In addition, the various lighting portions have a level of homogeneity entirely comparable to those obtainable with O-led technology, while having a significantly lower complexity and cost than the latter technology.

The advantages described above are obtained regardless of the number and arrangement of the segmentations of the light guides used. In addition, each sector or segment is illuminated homogeneously and uniformly without allowing the leakage of light beams or sectors or segments not expressly lit. In this way, the division into several parts of the light guide and in general of the vehicle light is always respected in all operating conditions of the light. Each sector or segment is switched on or off independently of adjacent sectors or segments without running any risk of unwanted light beam leakage.

Therefore, it is possible to send light signals that are always clear and perfectly understandable, i.e. it is possible to turn on segments to form specific light patterns with graphic effects and/or light messages that are always clear and distinct, precisely because the activation of the individual segments or portions is always accurate and there are no unwanted light leaks.

In addition, the lighting and/or signalling devices of the present invention have an extremely small footprint so that they are suitable to be applied both inside and outside the vehicle; furthermore, their reduced thickness facilitates their positioning in various positions since they do not require modification of the structure in which they are placed and do not require particularly deep housings.

The lighting and/or signalling devices of the present invention may be both planar and curved and therefore fit to be positioned at any point since they can easily be integrated into the curved lines of the bodywork and/or dashboard without any difficulty.

There are no limitations in terms of geometry or pattern or shape of the lighting faces obtainable.

The lighting patterns are also characterized by a remarkable uniformity and homogeneity of the light beam diffused outside the device.

Consequently, thanks to the present invention, it is possible to obtain a luminous pattern, i.e. any lighting surface, or having any geometric shape, while maintaining a high energy efficiency and homogeneity of lighting of the pattern.

The solution is simple to achieve, with limited costs, weights and dimensions.

A person skilled in the art may make numerous modifications and variations to the lighting and/or signalling devices described above so as to satisfy contingent and specific requirements while remaining within the sphere of protection of the invention as defined by the following claims.

Claim 1:
Lighting and/or signalling device (<NUM>), in particular for the automotive sector, comprising:
- at least two LED light sources (<NUM>',<NUM>"), powered and activated separately, each facing a respective light input wall (<NUM>',<NUM>") of a corresponding light guide (<NUM>',<NUM>"),
- wherein said light guides (<NUM>',<NUM>' ) are suitable to transmit and emit the light of said LED light sources (<NUM>' ,<NUM> " ) through at least two distinct lighting faces (<NUM>,<NUM> at a front wall (<NUM> ) of the lighting device, permeable to light, the light guides (<NUM>',<NUM>") being provided with diffuser extractor elements (<NUM>) arranged on a rear wall (<NUM>) of the light guides (<NUM>' ,<NUM> "), opposite the front wall (<NUM>), and shaped so as to extract the light outside the lighting and/or signalling device,
- wherein said light guides (<NUM>',<NUM>") are juxtaposed and adjacent to each other at at least one respective inner wall (<NUM>),
- wherein said light guides (<NUM>',<NUM>") are mechanically and optically separated by barrier elements (<NUM>) which prevent the passage of light between the light guides (<NUM>',<NUM>") at said at least one inner wall (<NUM>),
wherein said barrier elements (<NUM>) are separator septa opaque to the light extending from the rear wall (<NUM>) to at least said front wall (<NUM>), crossing it completely,
characterised in that said extractor diffuser elements (<NUM>) are shaped so as to extract the light at least partially towards the rear wall (<NUM>),
wherein at least one reflector element (<NUM>) is associated with each light guide (<NUM>',<NUM>' ') directly facing the respective diffuser extractor elements (<NUM>) so as to reflect the light towards the front wall (<NUM>), wherein said barrier elements (<NUM>) extend from the reflector element (<NUM>) to at least said front wall (<NUM>), crossing it completely,
wherein said barrier elements (<NUM>) completely cross any portion transparent to light rays arranged beyond the reflector element (<NUM>) toward the front wall (<NUM>), comprising the latter.