Patent Description:
In the field of motor vehicles, a vehicle luminous device, for example a pixelated tail lamp, known to a person skilled in the art is adapted to display a pictogram, visible from outside of the vehicle, at several meters. Such luminous devices may be composed of a plurality of homogenous light emitting surfaces, a plurality of light source supports, a plurality of light sources, and a plurality of masks having a plurality of cavities through which the light emitted by the light sources is sent towards an outer lens. The cavities of the masks separate light beams of each LED to make sure that one LED illuminates one pixel so that the shadowing effect can be prevented. The light source supports, the light sources, and the masks are arranged in such a way that they cooperate to produce a good luminous homogeneity of the pixels over the plurality of surfaces/areas. However, there is a possibility of light leakage between adjacent light areas when both the adjacent areas are not lit at the same time. The cavities of the masks may act as physical barriers to reduce the light leakage between the adjacent light areas. It is necessary the masks have to follow the curvature of the outer lens. It is also necessary that the masks should be rigidly positioned and the tolerances between different parts of the lighting module should be maintained due to high optical requirements.

Known vehicle luminous devices are disclosed in the documents <CIT> and <CIT>.

An object of the invention is to alleviate the above mentioned problems. To be more precise, an object of the invention is to provide a curved interlocking mask structure having a plurality of masks for a vehicle luminous device, for example, a pixelated light module.

Another object of the present invention is to provide different locking mechanisms to provide a curved interlocking mask structure of the vehicle luminous device. Another object of the present invention is to reduce the tooling cost for making the curved interlocking mask structure of the vehicle luminous device.

Another object of the present invention is to make the plurality of masks of the curved interlocking mask structure in a single mold and can be oriented along different directions in the vehicle luminous device to produce homogeneous lit aspect.

According to the present invention, there is provided a luminous device for an automotive vehicle comprising: a plurality of lighting modules juxtaposed along a given direction; and an outer lens arranged to project a light beam emitted from the plurality of lighting modules. Each lighting module comprises: a light source support mounted with a plurality of light sources on its first face and a mask disposed opposite to the first face of the light source support. The mask comprises a plurality of cavities through which light rays emitted from the plurality of light sources are directed towards the outer lens. The mask of each lighting module is provided with a locking means intended to connect masks of the plurality of lighting modules. Thus, the plurality of masks can be interlocked by the locking means to provide an interlocking mask structure that can be rigidly positioned in the lighting module. Further, in an embodiment, the locking means between the masks allow the masks to orient in different directions so that the light emitted by the light sources can be sent out in an efficient manner without light leakage between adjacent masks of the interlocking mask structure.

According to the present invention, the locking means is a flexible connecting link. Flexible means elastically flexible. With the use of the flexible connecting links to form the interlocking mask structure, it is possible to make the interlocking mask structure using a single mold, thereby reducing the number of molds and hence the tooling cost. Further, with the use of the flexible connecting links, any two masks of the mask structure can be oriented along different axes and thereby the homogenous-lit aspect can be obtained.

In a non-limiting embodiment of the present invention, the outer lens is curved and the masks associated with the plurality of lighting modules are arranged in a curved manner to follow the curvature of the outer lens. The molds of the masks are designed in such a way that when the masks are interlocked, the interlocked mask structure follows the curvature of the outer lens. For instance, the molds are designed in such a way that lateral sides of the masks are not parallel to each other so that when the masks are interlocked, the interlocked mask structure follows the curvature of the outer lens. For instance, each mask has a trapezoidal form. According to the curvature of the outer lens, the mold(s) can be designed such that when they interlock together, the interlocking structure follows the curvature of the outer lens.

In a non-limiting embodiment of the present invention, the masks of the plurality of lighting modules have the same dimensions. Advantageously, the tooling cost can be minimized or reduced by making the masks of the same dimensions.

In a non-limiting embodiment of the present invention, each lighting module further comprises a diffusing screen and/or an opaque grid, which has cells separated by opaque portions, and each cell is positioned over one cavity of the mask of the corresponding lighting module. The mask of each lighting module includes a first end, which faces the light source support, and a second end opposite to the first end, which faces the diffusing screen, and the opaque grid is arranged opposite to the diffusing screen. The diffusion screen allows for improved homogeneity of the lit appearance of each pixel. Further, the opaque grid is made of a thermoplastic material such as polycarbonate (PC) or poly (methyl methacrylate) (PMMA) and may be in the form of a self-adhesive film.

Thus, it will stick on to the diffusing screen. Other embodiments of the opaque grid can be suitable. For example, the opaque grid can be made of injected thermoplastic material, and positioned in front of the diffusing screen by fixation means such as clips or screws. The diffusing screen and the opaque grid avoids light pollution from one pixel to another pixel of a pixel matrix, which is formed by the cavities of the pluralities of masks.

Each cavity defines one pixel of the pixelated lamp. Each light source can be piloted individually by piloting means, so that a predefined pixelated image can be displayed.

According to another embodiment, the present invention also relates to a vehicle signaling lamp comprising at least one lighting module according to the present invention.

To complete the description and to provide a better understanding of the invention, a set of drawings is provided. Said drawings form an integral part of the description and illustrate an embodiment of the invention, which should not be construed as restricting the scope of the invention, but only as an example of how the invention can be carried out. The drawings comprise the following characteristics.

Embodiments will below be explained in detail by ways of examples with reference to the accompanied drawings. Throughout the description, same or similar reference numerals represent same or similar parts. The following description of the embodiments with reference to the drawings is intended to explain the general inventive concept of the present invention, instead of limiting it.

Vehicle luminous devices are associated with vehicles to perform different lighting and/or signaling functions and auxiliary functions. For instance, a pixelated tail lamp, one such luminous device, known to a person skilled in the art, is adapted to display a pictogram, visible from outside of the vehicle, at several meters.

A luminous device for an automotive vehicle is described according to an embodiment of the present invention. In a non-limiting embodiment, the vehicle is a motor vehicle. The luminous device according to an embodiment is a tail lamp of an automotive vehicle. The tail lamp is a pixelated tail lamp. As previously mentioned, with the pixelated tail lamp, a pictogram in particular can be displayed. According to an embodiment of the present invention, the vehicle luminous device comprises a plurality of lighting modules juxtaposed along a given direction, for instance, along a transverse direction of the vehicle; and an outer lens configured to project a light beam emitted from the plurality of lighting modules. <FIG> illustrates a lighting module of a vehicle luminous device, according to an embodiment of the present invention. For the sake of brevity and explanation, only one lighting module is shown in <FIG>. It is understood to a person skilled in the art that the luminous device includes one or more lighting modules. The lighting module <NUM> comprises a longitudinal axis Az which extends from the front to the rear of the motor vehicle and which is parallel to the vehicle axis (not illustrated). It should be noted that lighting module <NUM> can be arranged in other orientations. In this case, the longitudinal axis Az has orientation corresponding substantially to the direction in which the lighting module <NUM> is intended to be observed.

Each lighting module <NUM> of the luminous device <NUM> comprises a light source support <NUM> mounted with a plurality of light sources <NUM> on its first face, and a mask <NUM> disposed opposite to the first face of the light source support <NUM>. For instance, the light source support <NUM> is a plane electronic holder. The light source support <NUM> extends along a transverse axis Ax that is perpendicular to the longitudinal axis Az of the lighting module <NUM>. In a non-limiting example, the light source support <NUM> is a printed circuit board, otherwise known as PCB. In a non-limiting example, the lighting module <NUM> comprises two light source supports <NUM> positioned with an angle between them, as it is visible on <FIG>. In a non-limiting embodiment, light sources <NUM> are semiconductor light sources, for instance, light emitting diodes (LEDs). For example, the LEDs may be OLEDs (organic LEDs), AMOLEDs (Active-matrix-organic-LEDs) or FOLEDs (flexible OLEDs).

The mask <NUM> comprises a plurality of cavities <NUM> through which light rays emitted from the plurality of light sources <NUM> are directed towards the outer lens <NUM>. For clarity, only some of the cavities <NUM> have been referenced in <FIG>. In the luminous device <NUM>, the mask <NUM> of each lighting module <NUM> are provided with a locking means intended to juxtapose and connect masks of the plurality of lighting modules <NUM> along a transverse axis (not shown in Figures) of the luminous device <NUM>.

The light sources <NUM> are configured to emit light rays that will pass through cavities <NUM> of the mask <NUM>. Each light source <NUM> is arranged opposite a single cavity. The mask has two ends, a first end of which faces the first face of the support <NUM> and a second end of which is opposite the first end, facing a diffusing screen <NUM>. Each mask <NUM> includes cavities <NUM> bounded by partitions that form the walls of the cavities. The cavities form an array of pixels. The pixel array allows a pictogram or moving image to be formed by turning on the appropriate light sources <NUM> for the pictogram or moving image to be formed. Thus, in the non-limiting embodiment, the luminous device <NUM> can display a suitable pictogram visible at several meters to warn a vehicle behind the motor vehicle. This improves the safety of the occupants of the motor vehicle and provides early warning or other information to the following vehicle or a pedestrian or a bicycle etc..

According to a non-limiting embodiment, the lighting module <NUM> further comprises an opaque grid <NUM>, which has cells/apertures <NUM> separated by opaque portions, and each cell is positioned over one cavity <NUM> of the mask of the corresponding lighting module <NUM>. For clarity, only some of the apertures have been referenced in <FIG>. The apertures have the same shape as pixels. Thus, in the same way as the pixels, they have hexagonal shape. The set of apertures also form a honeycomb. However the apertures and the pixels could have other forms, for example square, rectangle, triangle or other polygons, or circle, ellipse, oval. The form may be different from one aperture and/or pixel to another one. Advantageously, they are arranged in a matrix. Advantageously, the apertures <NUM> have the same shape as the pixels. The mask <NUM> of the lighting module <NUM> includes a first end, which faces the light source support <NUM>, and a second end opposite to the first end, which faces the diffusing screen <NUM>, and the opaque grid <NUM> is arranged opposite to the diffusing screen <NUM>. The diffusing screen <NUM> allows for improved homogeneity of the lit appearance of each pixel. In non-limiting embodiments, the diffusing screen <NUM> is grain structure or white. It mixes the light rays from the light sources <NUM> that pass through the cavities <NUM> to have homogeneous light. In a non-limiting mode of realization, the diffusing screen <NUM> is made of a plastic material, such as PC or PMMA. In a non-limiting embodiment, the opaque grid <NUM> is made of polycarbonate and in the form of self-adhesive film. Thus, it will stick on the diffusing screen <NUM>. The diffusing screen <NUM> and the opaque grid <NUM> avoids light pollution from one pixel to another pixel of the pixel matrix.

In the exemplary illustration shown in <FIG>, the lighting module <NUM> is provided with two supports <NUM> each comprising a plurality of light sources <NUM> and two masks <NUM>, each of which is arranged to one of the supports <NUM>. Two supports <NUM> form a certain angle between them. This makes it possible to adapt to the curved shape of the luminous device <NUM> in which the lighting modules <NUM> are integrated. It should be noted that using several supports instead of single support reduces the manufacturing cost of the lighting module <NUM>. Indeed, since the dimensions of the luminous device <NUM> are large, it is economical to manufacture smaller supports instead of a single large support. Further, the exemplary lighting module depicted in the <FIG> includes two diffusing screens and two opaque grids. However, it is understood by a person skilled in the art that the present invention is not limited to two supports, two diffusing screens, and two opaque grids in the lighting modules. The lighting module could comport more than two of these elements, and/or other additional elements.

The luminous device <NUM> when assembled with the plurality of lighting modules <NUM>, the masks <NUM> of the lighting module <NUM> have to be properly arranged such that the masks <NUM> should be rigid and the tolerances between different parts of the luminous device <NUM> is maintained. To ensure that the masks <NUM> of the luminous device <NUM> are rigidly positioned and to follow a curvature of the outer lens, the present invention provides a curved interlocking mask structure formed by connecting the masks <NUM> of the lighting modules <NUM> of the luminous device <NUM>.

The mask <NUM> of each lighting module <NUM> is provided with a locking means intended to juxtapose and connect masks <NUM> of the plurality of lighting modules <NUM> along a transverse axis of the luminous device <NUM>. Thus, the plurality of masks <NUM> can be interlocked by the locking means to form the interlocking mask structure that can be rigidly positioned in the luminous device <NUM>.

<FIG> illustrates an unassembled state of curved interlocking mask structure having a plurality of masks for a vehicle luminous device, according to an embodiment which is not according to the invention. <FIG> illustrates an assembled state of a curved interlocking mask structure having a plurality of masks for a vehicle luminous device, according to an embodiment which is not according to the invention.

In one embodiment, the masks <NUM> of the lighting module <NUM> may be interlocked by locking means formed integrally with each mask <NUM>. According to this embodiment, as can be seen from the <FIG>, the locking means formed with each mask <NUM> includes at least one notch <NUM> on its a first lateral side <NUM> and at least one protrusion <NUM> on its a second lateral side <NUM> opposite to the first lateral face <NUM>. For the sake of explanation, each mask <NUM> is formed with two notches <NUM> on its first lateral side <NUM> and two protrusions <NUM> on its second lateral side <NUM>. However, it is understood to a person skilled in the art that each <NUM> mask may include plurality of notches and plurality of protrusions, without any limitation. During assembly, the at least one protrusion <NUM> of a first mask can be engaged in the corresponding at least one notch <NUM> of an identical mask juxtaposed horizontally along the transverse axis of the luminous device <NUM> to form the curved interlocking mask structure. Advantageously, with this configuration, each mask <NUM> can be molded independently and can be assembled together using the notches <NUM> and protrusions <NUM> to provide the interlocking mask structure. Hence, with this configuration, the process of molding can be simplified.

<FIG> illustrates a curved interlocking mask structure having a plurality of masks for a vehicle luminous device, according to an embodiment of the invention.

According to this embodiment, the masks of the lighting module are interlocked by locking means, which is a flexible connecting link <NUM>, and is elastically flexible. The curved interlocking mask structure according to this embodiment includes a plurality of masks <NUM> in which adjacent masks are connected by a flexible connecting link <NUM>, as can be seen in the <FIG>. The masks <NUM> of this embodiment may be injected in the same mold and demolding axis of the masks are in the same direction. <FIG> illustrates a mold position of a pair of masks of the curved interlocking mask structure shown in <FIG>. As can be seen from the <FIG>, a demolding axis A of a first mask is in the same direction as a demolding axis B of a second mask, and both the masks are connected using the flexible connecting link <NUM>. The flexible connecting links enable the injection of the masks in the same mold. Advantageously, the links <NUM> are connected to the two adjacent masks <NUM> respectively on one edge between two faces of each of these masks, comprising the lateral facing faces of said two masks. This configuration ensures an easier molding as there is no gap between the mask and the link in direction of the respective demolding axis A and B. <FIG> illustrates an assembly position of a pair of masks of the curved interlocking mask structure shown in <FIG>. As can be seen from the <FIG>, a demolding axis A of a first mask and a demolding axis B of a second mask are oriented in different directions, and both the masks are connected using the flexible connecting link <NUM>. Although a single flexible connecting link is shown in the figures to connect the two adjacent masks, it is understood to a person skilled in the art that adjacent masks may be connected using more than one flexible connecting link.

When the curved mask interlocking structure is assembled in the luminous device <NUM>, with the help of the flexible links <NUM>, the masks <NUM> can be oriented in different directions, and thus the homogenous-lit aspect can be realized. According to this embodiment, it is possible to make the interlocking mask structure using a single mold, thereby reducing the tooling cost.

Also, the skilled person readily realizes that the different embodiments described herein may be combined freely to obtain new combinations.

Claim 1:
A luminous device (<NUM>) for an automotive vehicle comprising:
a. a plurality of lighting modules (<NUM>) juxtaposed along a given direction;
b. an outer lens (<NUM>) arranged to project a light beam emitted from the plurality of lighting modules (<NUM>), wherein each lighting module (<NUM>) comprises:
c. a light source support (<NUM>) mounted with a plurality of light sources (<NUM>) on its first face; and
d. a mask (<NUM>) disposed opposite to the first face of the light source support (<NUM>), wherein the mask (<NUM>) comprises a plurality of cavities (<NUM>) through which light rays emitted from the plurality of light sources (<NUM>) are directed towards the outer lens (<NUM>); and
characterized in that, the mask (<NUM>) of each lighting module (<NUM>) is provided with a locking means intended to connect masks of the plurality of lighting modules (<NUM>),
wherein the locking means is a flexible connecting link (<NUM>).