FR3043755A1 - LIGHT GUIDE (S) LIGHT DEVICE HAVING OVERMOULED (S) OPALINE (S) STRUCTURE (S) - Google Patents

Abstract

A lighting device (DE) comprises a light guide (GL), having two opposite ends, at least one of which is adapted to receive light, and a reflector (RL) having a concave section and intended to be placed facing a rear face (FR) of the light guide (GL) to reflect towards a front face (FV) of the light guided for its transfer to the outside to ensure a photometric function. This light guide (GL) comprises a structure (SS) at least partially overmolded on at least part of its front face (FV), made of an opaline-type material, and suitable for diffusing outwards part of the light guided and reflected towards the front face (FV) to ensure substantially uniform illumination participating in the photometric function.

Description

The invention relates to lighting devices, and more specifically those which comprise at least one light guide, powered by a light guide. light source, and a reflector.

The term "lighting device" is intended here to mean a light device capable of providing or participating in at least one photometric lighting or signaling function or of a light effect, possibly decorative.

In certain fields, such as for example vehicles, possibly of the automotive type, lighting devices comprising at least one light guide having two opposite ends, at least one of which receives light (from a light source), are used. light source), and a reflector, having at least one concave section and placed opposite a rear face of the light guide, at a small distance, to reflect towards a front face of the latter of the guided light in order to its transfer to the outside to ensure or participate in a photometric function.

The light guide is for example made of polycarbonate (or PC) or polymethylmethacrylate (or PMMA).

In order to allow a good homogeneity of the lighting, it has been proposed, in particular in the patent document FR 2953276, to place a screen, rigid and of opaline type, in front of the front face of the light guide, at a short distance. By "opal screen" is meant here a screen which is not quite opaque and not quite translucent so as to induce a substantially homogeneous light diffusion.

This rigid screen has a concave section so as to house a front portion of the light guide and thus receive the light coming out of the front face of the latter. The main disadvantage of this type of lighting device lies in the fact that it has a large footprint because the reflector and the rigid screen are distant from the light guide.

Moreover, this type of lighting device can only ensure a single photometric function of non-regulatory type (that is to say not defined by a rule) because the front face of its light guide is surrounded by its opaline rigid screen. The purpose of the invention is in particular to improve the situation.

It proposes for this purpose a lighting device comprising at least one light guide, having two opposite ends of which at least one is adapted to receive light, and a reflector, having at least one concave section and intended to being placed opposite a rear face of the light guide to reflect towards a front face of the latter of the guided light for its transfer to the outside to participate in a photometric function.

This lighting device is characterized in that its light guide comprises at least one structure at least partially overmolded on at least part of its front face, made of an opaline-type material, and suitable for diffusing outwardly at least a portion of the light, guided and reflected towards the front face, to provide substantially uniform illumination participating in this photometric function.

This overmoulding on the front face of the light guide significantly reduces the overall size of the assembly consisting of the light guide, each overmolded structure and the reflector.

The lighting device according to the invention can comprise other characteristics that can be taken separately or in combination, and in particular: in a first embodiment, it can comprise at least two structures separated by a free zone allowing a part of the light, guided and reflected towards the front face of the light guide, to be transferred outward to participate in another photometric function; in a second embodiment (compatible with the first mode), its / each structure may be totally overmolded on at least a portion of the front face of the light guide; in a third embodiment (compatible with the first and second modes), its structure may comprise at least one central part overmolded on a part of the front face of the light guide and extended on at least one side by a lateral part as well. overmolded on another part of the front face of the light guide, having a chosen shape, different from that of the central part, and adapted to ensure a three-dimensional effect (or 3D); in a fourth embodiment, its structure may comprise a first portion overmolded on a portion of the front face of the light guide and at least a second portion extending this first portion away from this front face; in a fifth embodiment, it may comprise at least two light guides. In this case, its structure may be partially overmolded on part of the front face of each of the light guides; its structure may comprise a central portion overmolded on a portion of the front face of the light guides and two end portions extending this central portion on two opposite sides at a distance from the front face of each of the light guides; it may comprise at least one light source capable of supplying light to one end of at least one light guide. The invention also proposes a vehicle optical unit, possibly of automotive type, comprising at least one lighting device of the type of that presented above. The invention also proposes a vehicle, possibly of automobile type, and comprising at least one lighting device of the type of the one presented above or at least one optical block of the type of that presented above. Other characteristics and advantages of the invention will appear on examining the detailed description below, and the accompanying drawings (obtained in CAD / CAD ("Computer Aided Design / Computer Aided Drawing"), of where the apparently discontinuous character of certain lines), in which: FIG. 1 schematically illustrates, in a perspective view, a part of a first embodiment of a lighting device according to the invention, FIG. 2 schematically illustrates, in a perspective view, another part of the illumination device of FIG. 1; FIG. 3 schematically illustrates, in a perspective view, a part of a second exemplary embodiment of a device of FIG. According to the invention, FIG. 4 schematically illustrates, in a perspective view, part of a third embodiment of a lighting device according to the invention, and FIG. 5 illustrates schematically, in a perspective view, a portion of a fourth embodiment of a lighting device according to the invention. The invention aims in particular to provide a lighting device DE for ensuring or participating in at least one photometric function of lighting or signaling or light effect, possibly decorative.

In what follows, it is considered, by way of non-limiting example, that the lighting device DE is intended to equip an optical block of a vehicle of the automotive type, such as a car. But the invention is not limited to this application. Indeed, a lighting device DE may be an equipment in itself (possibly including its own housing), or may be part of another equipment that a vehicle optical unit. Thus, a lighting device DE can be part of any vehicle (land, sea (or fluvial), or air), any installation, including industrial type, any device ( or system), and any building. In addition, a lighting device DE can provide indoor or outdoor lighting.

Furthermore, it is considered in the following, by way of non-limiting example, that the optical unit (comprising at least one lighting device DE) is a rear lamp providing at least one photometric signaling function, such as a position light function (or night light or lantern). But the invention is not limited to this application. Indeed, the lighting device DE, according to the invention, is a light device that can participate in (or ensure) at least one photometric function of lighting or signaling or light effect, possibly decorative. Thus, in the non-limiting case of a vehicle, it can participate in a photometric signaling function, such as a change of direction indicator function, a stop light function, a reversing light function, position light function, a daytime running light function (or DRL (for "Daytime running Light (or Lamp)" -sign lighting illuminated automatically when the vehicle is put into operation during the day), or a reception function (or courtesy), or a photometric function of light effect, possibly decorative (or ambience). Note that the optical block could also be a beacon (or front projector).

FIGS. 1 and 2 show schematically a portion of a first non-limiting exemplary embodiment of a lighting device DE according to the invention.

As illustrated in FIGS. 1 and 2, a lighting device DE according to the invention comprises at least one light guide GL and one reflector RL. Note that in Figures 2 to 5 the reflector RL is materialized in section and dotted so as not to introduce overload.

It will also be noted that in the non-limiting examples of FIGS. 1 to 4, the lighting device DE comprises only one light guide GL. But it could include several (at least two) as in the non-limiting example of Figure 5.

Although this appears only partially in the figures, the (each) light guide GL comprises two opposite ends E1 and E2, at least one of which is adapted to receive light provided by a light source.

The light source is able to generate photons. These photons may be white or of color, for example red or orange (in the case of a flashing function).

For example, the light source may comprise at least one light diode, such as a light emitting diode (or LED) or a laser diode or an OLED structure (organic LED).

Also for example, and as illustrated in non-limiting manner in FIGS. 1 and 5, the light source may be installed on a PS support plate. This PS support plate may, for example, be a printed circuit board (PCB), rigid or flexible ("Flex" type).

Also for example, the (each) light guide GL may be made of polycarbonate (or PC) or PMMA.

Furthermore, the (each) light guide GL comprises a rear face FR defining a rear portion and a front face FV delimiting a front portion, and may extend in a main direction or have at least one curvature.

Note that in the non-limiting examples of Figures 1 to 5, the (each) light guide GL is fed only by its first end E1. But it could be powered by its second end E2 or by its first E1 and second E2 ends.

The reflector RL has at least one concave section and is intended to be placed facing the rear face FR of (each) light guide GL to reflect towards the front face FV of the latter (GL) of the guided light, issue at least one light source, for its transfer to the outside to participate in (or ensure) at least one photometric function.

The number of concave sections of the reflector RL may depend on the number of light guides GL of the lighting device DE, but this is not mandatory. Indeed, in the non-limiting example of FIG. 5, the lighting device DE comprises two light guides GL and a reflector RL with two concave sections each housing a part of the rear part of one of the light guides GL. . But in a variant the lighting device DE could comprise two light guides GL and a reflector RL with a single concave section housing part of the rear part of the two light guides GL.

For example, the reflector RL may be made of acrylonitrile butadiene styrene (or ABS).

According to the invention, the light guide GL comprises at least one SS structure which is at least partially overmolded on at least part of its front face FV, made of an opaline-type material, and suitable for diffusing outwardly a at least part of the light, guided and reflected towards this front face FV, to provide substantially uniform illumination participating in the (a) photometric function of its lighting device DE.

Thanks to this overmolding on the front face FV of the light guide GL, the overall size of the assembly constituted by the light guide GL, each overmolded structure SS and the reflector RL is significantly reduced, which facilitates its implementation, in particular in an optical block.

It should be noted that each overmolded structure SS may, for example, be produced by injection of a synthetic material such as opaline polycarbonate (or PC).

Several embodiments of the lighting device DE can be envisaged. Four of them are described below (with variations) with reference to FIGS. 1 to 5.

In a first embodiment shown in non-limiting manner in FIGS. 1 and 2, the light guide GL comprises two structures SS which are totally overmolded on two parts distant from the front face FV of the light guide GL. These two SS structures thus marry the respective shapes of the two remote parts of the front face FV. It should be noted that these two SS structures are not necessarily identical. It should also be noted that more than two SS structures could be overmolded.

These two SS structures diffuse part of the light, guided and reflected towards the front face FV, to provide substantially uniform illumination participating in a photometric function of the lighting device DE. This photometric function may be a signaling function, for example a position or daytime running light (or DRL), or a light effect function, possibly decorative (for example three-dimensional due to the thickness of the overmoulding). .

Moreover, the two SS structures being separated by a free zone ZL, part of the light, guided and reflected towards the front face FV, can be transferred via this free zone ZL outwardly to advantageously participate in another photometric function. of the lighting device DE. This other photometric function can be a signaling function, such as a position light (or night light or lantern), a change of direction indicator or a reversing light, or a light effect function, possibly decorative. Note that since the free zone ZL is devoid of opaline overmolding, the other photometric function may be regulatory (that is, defined by a rule).

In a second embodiment shown in non-limiting manner in FIG. 3, the light guide GL comprises only one SS structure which is totally overmolded on at least part of its front face FV. This SS structure therefore follows the shape of the front face FV. In this case, the SS structure diffuses part of the light, guided and reflected towards the front face FV, to ensure a substantially homogeneous illumination participating in the photometric function of the lighting device DE. This photometric function may be a non-regulatory signaling function, such as a position light (or pilot light or lantern), a change of direction indicator or a reversing light, or a light effect function, possibly decorative ( for example three-dimensional because of the thickness of overmoulding).

In a variant of the second embodiment, not illustrated, the light guide GL could comprise at least one SS structure comprising at least one central portion overmolded on a portion of the front face FV of the light guide GL and extended on at least one side by a side portion also overmolded on another part of the front face FV of the light guide GL, having a selected shape, different from that of the central portion, and adapted to ensure a three-dimensional effect (or 3D).

For example, the central portion may have a thickness less than that of each side portion. The opposite is also possible. This difference in thickness makes it possible to induce the three-dimensional effect.

Note that one can also consider creating at least one groove or rib in the thickest part.

In a third embodiment shown in non-limiting manner in FIG. 4, the light guide GL comprises only one SS structure which comprises a first portion P1 overmolded on a portion of the front face FV and at least one second portion P2 extending this first part P1 away from the front face FV. Here, the distance increases as it moves away from the first portion P1, as an example. In the nonlimiting example illustrated in FIG. 4, the first overmolded portion P1 is extended on two opposite sides by two second portions P2.

This embodiment is intended to widen the diffusion zone of the SS structure, and thus to increase the homogeneous illumination surface.

In a fourth embodiment shown in non-limiting manner in FIG. 5, the lighting device DE comprises two light guides GL whose rear parts are partially housed in two concave sections of the reflector RL. Moreover, the single structure SS is partially overmolded on a portion of the front face FV of each of the light guides GL.

More precisely, in this fifth embodiment the structure SS comprises a central part PC which is overmolded on a part of the front face FV of the light guides GL, and two end parts PE which extend this central part PC on two sides. opposed at a distance from the front face FV of each of the light guides GL. Here, the distance is increasing as you move away from the central part PC, as an example.

This embodiment is intended to increase the intensity of the illumination and to significantly widen the diffusion zone of the SS structure, and thus to increase the homogeneous illumination surface. The invention offers several advantages, among which: a significant reduction in the bulk, a great homogeneity of the scattered light, a reduction in the number of parts to be assembled due to the absence of a screen, and therefore a increased simplicity of assembly and tooling required, and reduced costs.

Claims (10)

A lighting device (DE) comprising at least one light guide (GL), having two opposite ends, at least one of which is adapted to receive light, and a reflector (RL) having at least one section concave and intended to be placed facing a rear face (FR) of said light guide (GL) to reflect to a front face (FV) of the latter (GL) of the guided light for its transfer to the external to participate in at least one photometric function, characterized in that said light guide (GL) comprises at least one structure (SS) at least partially overmolded on at least part of said front face (FV), made of a material opaline type, and adapted to diffuse outwardly at least part of said light, guided and reflected to said front face (FV), to provide substantially uniform illumination participating in said photometric function. 2. Device according to claim 1, characterized in that said structure (SS) is completely overmolded on at least part of said front face (FV). 3. Device according to one of claims 1 and 2, characterized in that it comprises at least two structures (SS) separated by a free zone (ZL) allowing a portion of said light, guided and reflected towards said front face (FV), to be transferred outward to participate in another photometric function. 4. Device according to one of claims 1 to 3, characterized in that said structure (SS) comprises at least a central portion overmolded on a portion of said front face (FV) of the light guide (GL) and extended on to at least one side by a lateral portion also overmolded on another part of said front face FV of the light guide GL, having a chosen shape, different from that of the central part, and adapted to ensure a three-dimensional effect. 5. Device according to claim 1, characterized in that said structure (SS) comprises a first portion (P1) overmolded on a portion of said front face (FV) and at least a second portion (P2) extending said first portion (P1). ) away from said front face (FV). 6. Device according to claim 1, characterized in that it comprises at least two light guides (GL), and in that said structure (SS) is partially overmolded on a portion of said front face (FV) of each said light guides (GL). 7. Device according to claim 6, characterized in that said structure (SS) comprises a central portion (PC) overmolded on a portion of the front face (FV) of the light guides (GL) and two end portions (PE ) extending said central portion (PC) on two opposite sides at a distance from said front face (FV) of each of said light guides (GL). 8. Device according to one of claims 1 to 7, characterized in that it comprises at least one light source adapted to supply light to an end of said at least one light guide (GL). 9. Vehicle optical unit, characterized in that it comprises at least one lighting device (DE) according to one of the preceding claims. 10. Vehicle, characterized in that it comprises at least one optical unit according to claim 9.