EP3354972A1 - Lighting device having a mask with diamond tip patterns - Google Patents

Abstract

A lighting device (DE) comprises at least one light source (SL) capable of generating photons and a mask (M) able to let the photons generated at predefined locations. The mask (M) comprises a front face (FV), facing outwards, and provided with three-dimensional elements (ET) participating together in a predefined photometric function and each having a general diamond point shape defined by at least two opaque facets (FOj) contiguous and inclined relative to each other and at least two transparent facets (FTj) contiguous and each extending in an inclined manner, in one of the predefined locations, one of the opaque facets (FOj ) towards an opaque facet (FOj) of at least one other neighboring three-dimensional element (ET).

Description

The invention relates to lighting devices, and more specifically those which comprise at least one light source associated with a mask to ensure at least one predefined photometric function.

In what follows, the term "lighting device" means a light device that can provide at least a photometric function of lighting or signaling or light effect, possibly decorative.

In certain fields, such as for example vehicles, possibly of the automotive type, lighting devices, such as those defined above, are used to ensure at least one predefined photometric function, for example a position light function. (or pilot light or lantern) or a daylight running function (or DRL (for "Daytime running Light (or Lamp)" - illuminated automatically when the vehicle is in operation during the day)).

In lighting devices of the type defined above, the mask is a part, usually made of plastic material, and charged to prevent the passage of photons generated except at predefined locations. In other words, the mask comprises opaque zones, which possibly appear when they are backlit, and one or more transparent zones passing photons.

Sometimes, the mask has on its front face patterns that appear when they are backlit by the back and are virtually invisible in the absence of backlight. These patterns are generally defined by metallization and laser ablation, or by partial metallization by means of a metallization saving mask, or by screen printing on a glued or overmolded film, or by printing.

This type of mask, which is described in particular in the patent document FR 3011312 , usually only defines patterns two-dimensional (or 2D), without real effect of relief (or 3D), and intended exclusively to produce a style of light effect, sometimes decorative. Consequently, these patterns do not generally participate in a predefined photometric function of the lighting device of which they form part, which forces to add to the latter or to a neighboring equipment optical elements allowing the outgoing photons to satisfy the conditions that define this photometric function predefined. Note that in a vehicle, the optical elements are generally defined on one side of a protective glass placed at the interface with the outside. These optical elements, which are for example lenses, facets, shots, or streaks, are visible and therefore can interfere with a desired style effect, or even be considered as defects.

The invention is therefore particularly intended to improve the situation.

In particular, it proposes for this purpose a lighting device comprising at least one source of light capable of generating photons and a mask capable of allowing the photons generated to pass through predefined locations.

This lighting device is characterized in that its mask comprises an outward facing face, and provided with three-dimensional elements which together participate in a predefined photometric function and each having a general shape in a diamond point defined by minus two opaque facets contiguous and inclined relative to each other and at least two transparent facets contiguous and each extending in an inclined manner, in one of the predefined locations (where the photons pass), one of the facets opaque to an opaque facet of at least one other neighboring three-dimensional element.

Thanks to these three-dimensional elements (or 3D) diamond tip, we have 3D patterns that not only participate in a light effect, possibly decorative, but also actively contribute together to the photometric function predefined, which avoids to have to add additional optical elements to their lighting device or to a neighboring equipment.

• les éléments tridimensionnels peuvent être placés les uns par rapport aux autres de sorte que leurs facettes transparentes délivrent ensemble des photons dans un secteur angulaire horizontal prédéfini et dans un secteur angulaire vertical prédéfini ;
  • ➢ le secteur angulaire vertical prédéfini peut être subdivisé en un sous-secteur supérieur et un sous-secteur inférieur qui, d'une part, se prolongent mutuellement de part et d'autre d'un axe ayant une direction prédéfinie, et, d'autre part, ont respectivement des première et seconde extensions angulaires verticales prédéfinies ;
    • la première extension angulaire verticale prédéfinie peut être comprise entre 5° et 25°, et la seconde extension angulaire verticale prédéfinie peut être comprise entre 5° et 25° ;
• les facettes transparentes de chaque élément tridimensionnel peuvent être inclinées l'une par rapport à l'autre d'un angle compris entre 105° et 125° ;
• au moins les facettes opaques peuvent être polies, et au moins des zones d'une face arrière du masque, situées derrière les facettes transparentes, peuvent être polies ;
• les facettes transparentes des éléments tridimensionnels peuvent se prolonger mutuellement le long de lignes qui s'intersectent et où les photons définissent des bandes lumineuses qui se croisent ;
• chaque facette opaque peut être revêtue sur la face avant d'une couche métallique propre à assurer son opacité ;
• chaque facette transparente peut présenter une transparence résultant d'une ablation, au moyen d'un laser, d'une couche métallique préalablement déposée, ou d'un dépôt d'une épargne pendant une phase de métallisation ;
• il peut comprendre un réflecteur propre à réfléchir les photons générés vers une face arrière du masque, opposée à la face avant.

The lighting device according to the invention may comprise other features that can be taken separately or in combination, including:

• the three-dimensional elements can be placed relative to each other so that their transparent facets together deliver photons in a predefined horizontal angular sector and in a predefined vertical angular sector;
  • The predefined vertical angular sector can be subdivided into an upper subsector and a lower subsector which, on the one hand, extend mutually on either side of an axis having a predefined direction, and, on the other hand, respectively have first and second predefined vertical angular extensions;
    • the first predefined vertical angular extension can be between 5 ° and 25 °, and the second predefined vertical angular extension can be between 5 ° and 25 °;
• the transparent facets of each three-dimensional element can be inclined relative to each other by an angle of between 105 ° and 125 °;
• at least the opaque facets can be polished, and at least areas of a rear face of the mask, located behind the transparent facets, can be polished;
• the transparent facets of the three-dimensional elements may extend mutually along intersecting lines and where the photons define intersecting light bands;
• each opaque facet may be coated on the front face of a metal layer to ensure its opacity;
• each transparent facet may have a transparency resulting from ablation, by means of a laser, of a previously deposited metal layer, or of a deposit of a saving during a metallization phase;
• it may include a reflector adapted to reflect the photons generated towards a rear face of the mask, opposite to the front face.

The invention also proposes a vehicle optical unit, possibly of automobile type, and comprising at least one device lighting of the type shown 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 and / or at least one optical block of the type of that presented above.

• la figure 1 illustre schématiquement, dans une vue en coupe longitudinale (XZ), un exemple de bloc optique comprenant un exemple de réalisation d'un dispositif d'éclairage selon l'invention,
• la figure 2 illustre schématiquement, dans une vue en perspective, un exemple de réalisation d'un masque d'un dispositif d'éclairage selon l'invention,
• la figure 3 illustre schématiquement, dans une vue en perspective, un exemple de réalisation d'un élément tridimensionnel du masque du dispositif d'éclairage de la figure 2,
• la figure 4 illustre schématiquement, dans une vue en coupe horizontale (XY), une représentation symbolique de deux blocs optiques arrière selon l'invention, avec les matérialisations d'angles d'observation interne et externe correspondant à un secteur angulaire horizontal prédéfini associé au bloc optique arrière gauche, et
• la figure 5 illustre schématiquement, dans une vue en coupe longitudinale (XZ), une représentation symbolique d'un bloc optique selon l'invention, avec les matérialisations du secteur angulaire vertical prédéfini et de ses sous-secteur supérieur et sous-secteur inférieur.

Other features and advantages of the invention will appear on examining the detailed description below, and the attached drawings, in which:

• the figure 1 illustrates schematically, in a longitudinal sectional view (XZ), an example of an optical block comprising an exemplary embodiment of a lighting device according to the invention,
• the figure 2 schematically illustrates, in a perspective view, an embodiment of a mask of a lighting device according to the invention,
• the figure 3 schematically illustrates, in a perspective view, an exemplary embodiment of a three-dimensional element of the mask of the lighting device of the figure 2 ,
• the figure 4 schematically illustrates, in a horizontal sectional view (XY), a symbolic representation of two rear optical units according to the invention, with the materializations of internal and external observation angles corresponding to a predefined horizontal angular sector associated with the rear optical block. left, and
• the figure 5 illustrates schematically, in a longitudinal sectional view (XZ), a symbolic representation of an optical block according to the invention, with the materializations of the predefined vertical angular sector and its upper subsector and lower subsector.

The object of the invention is in particular to propose an illumination device DE with a light source (s) SL and a mask M, capable of ensuring at least one predefined photometric function.

In the following, by way of nonlimiting example, the lighting device DE is intended to equip an optical block BO of a vehicle of automobile type, such as for example 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.

Furthermore, it is considered in the following, by way of non-limiting example, that the optical block BO (comprising at least one lighting device DE) is a rear light providing at least one photometric signaling function, for example 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 provide at least a photometric function of lighting or signaling or light effect, possibly decorative. Thus, it could, for example, provide a daylight running function (or DRL (for "Daytime running Light (or Lamp)" - light signaling automatically illuminated when the vehicle is operated during the day)).

On the Figures 1 to 5 , the direction X is a so-called longitudinal direction because it is parallel to a longitudinal side of a vehicle, the Y direction is a so-called transverse direction because it is perpendicular to the longitudinal sides of the vehicle and therefore perpendicular to the longitudinal direction X, and the direction Z is a vertical direction, perpendicular to the longitudinal direction X and transverse Y.

We have schematically illustrated on the figure 1 , a part of a vehicle optical block BO (here a taillight) comprising, in particular, a BB housing delimiting a portion of a cavity housing a lighting device DE according to the invention, as well as any other lighting means providing at least one other photometric function, and a protective glass GP, glass or plastic.

The BB housing is intended, here, to be secured to a portion of the body of a vehicle (here in a rear portion). It is realized in a rigid material, such as a plastic or synthetic material. In this case, it can be made by molding.

As illustrated on the figure 1 , a lighting device DE according to the invention comprises at least one light source SL and a mask M.

Each light source SL is able to generate photons for the mask M, directly or indirectly. For example, each light source SL may be a light-emitting diode of the conventional type (or LED ("Light-Emitting Diode") or organic type (or OLED ("Organic Light-Emitting Diode")), or a laser diode.

It will be noted, as illustrated without limitation on the figure 1 , that each light source SL can, for example, be installed on a support plate PS. This PS support plate may, for example, be a printed circuit board (PCB), rigid or flexible ("Flex" type).

The mask M is adapted to (or arranged to) pass the photons that are generated by the light source (s) SL in predefined locations. For example, it can be made by molding in a plastic material such as polycarbonate (or PC) or polymethylmethacrylate (or PMMA), or glass.

The color of the material in which the mask M is produced depends on the photometric function predefined in which it participates and / or the wavelength of the photons generated by the light source (s) SL. For example, its color may be red or orange, or white crystal, as needed. Moreover, and as illustrated without limitation on the figure 1 the mask M may have a non-zero average inclination with respect to a horizontal plane XY. For example, it (M) may be inclined relative to this horizontal plane XY by an angle of between 20 ° and 50 °.

This mask M comprises a front face FV, oriented towards the outside (and thus towards the protective glass GP), and a rear face FR, opposite to the front face FV and receiving the photons generated by the (the) source (s) ) SL light.

It will be noted, as illustrated without limitation on the figure 1 , that the lighting device DE may also include a clean reflector RP to reflect the photons, generated by the light source (s) SL, towards the rear face FR of the mask M. In this case, the photons generated by the light source (s) SL are initially directed to the RF reflector which reflects them to the rear face FR of the mask M. But in an alternative embodiment the lighting device DE may not include a reflector RP, and in this case the photons generated by the (the) source (s) ( s) of light SL go directly to the rear face FR of the mask M.

As illustrated on Figures 1 and 2 , the front face FV of the mask M is provided with three-dimensional elements ET which participate together in a predefined photometric function of the lighting device DE and each have a general shape in diamond point defined by at least two opaque facets FOj and at least two transparent facets FTj.

Here, the term "general shape diamond tip" means a polyhedron 3D faces (or facets) polygonal planar arranged with respect to each other in a manner similar to a diamond.

As illustrated without limitation on the figure 3 the opaque facets FOj of each three-dimensional element ET are contiguous and inclined with respect to each other. Moreover, the transparent facets FTj of each three-dimensional element ET are contiguous and each extend in an inclined manner, at one of the predefined locations (through which the received photons pass), one of the opaque facets FOj towards a facet opaque FOj of at least one other three-dimensional element AND neighbor.

It will be noted that in the example illustrated, not limitation, on figures 2 and 3 , the three-dimensional elements ET comprise two opaque facets FO1 (j = 1) and FO2 (j = 2) and two transparent facets FT1 (j = 1) and FT2 (j = 2). But a three-dimensional element ET can include any number of opaque facets FOj and thus transparent facets FTj, since this number is at least equal to two.

It will be understood that each three-dimensional element ET constitutes a 3D diamond-shaped pattern that appears when it is backlit by the rear face FR, and whose relief is enhanced (or even amplified) by the photons that emerge from each of them. its transparent facets FTj which extend its opaque facets FOj towards at least one other three-dimensional element AND neighbor. Therefore, the three-dimensional elements ET not only participate together in a light effect, possibly decorative, but also actively contribute together to the predefined photometric function of their lighting device DE. Thus, it is no longer necessary to add to the lighting device DE or to a neighboring equipment (such as for example the protective glass GP) additional optical elements, such as lenses, facets, blows, or streaks to satisfy the conditions that define the predefined photometric function. As a result, there is no longer any risk of harming a desired style effect, or visual impression of a manufacturing defect.

As illustrated without limitation on Figures 4 and 5 , the three-dimensional elements ET are preferably placed relative to each other (here in an optical block BO) so that their transparent facets FTj together deliver photons in a predefined horizontal angular sector and in a vertical sector SAV predefined predefined.

Here, the term "horizontal angular sector" means an angular sector included in a horizontal plane XY. Furthermore, here "vertical vertical sector SAV" means an angular sector included in a vertical plane XZ.

The horizontal angular sector and the vertical vertical sector SAV are predefined in order to satisfy the conditions which define the predefined photometric function which is provided by the lighting device DE (via the mask M).

For example, and as illustrated without limitation on the figure 4 the predefined horizontal angular sector can be defined according to an observer's internal observation angle SS1 with respect to an axis AX having a predefined direction and an external observation angle SS2 of this same observer with respect to to this same axis AX. This internal observation angle SS1 corresponds to the maximum internal angular separation of the observer with respect to the axis AX where he still perceives the light coming out of an optical block BO according to a predefined intensity. The external observation angle SS2 corresponds to the maximum external angular spacing of the observer with respect to the axis AX where he still perceives the light coming out of this same optical block BO according to a predefined intensity. In the example of the figure 4 , the angles SS1 and SS2 concern the left optical block BO.

In the case of a vehicle comprising a left rear optical block and a right rear optical block axis AX is the axis which is parallel to the longitudinal direction X of the vehicle and which passes through the median longitudinal plane XZ of the latter. This AX axis thus passes halfway between the left and right rear optical units (see figure 4 ).

For example, the internal observation angle SS1 can be between 30 ° and 60 °. Also for example, the external observation angle SS2 can be between 70 ° and 90 °.

Thus, when the photometric function is a position light (or lantern) function, the internal observation angle SS1 may be equal to 45 ° and the external observation angle SS2 may be equal to 80 °.

Also for example, and as illustrated without limitation on the figure 5 , the predefined SAV vertical angular sector can be subdivided into an upper sub-sector SS3 and a lower sub-sector SS4, on the one hand, extending mutually on either side of the axis AX (having a predefined direction) and, on the other hand, respectively having first and second predefined vertical angular extensions. This upper sub-sector SS3 corresponds to the maximum upper angular spacing of the observer with respect to the axis AX where it still perceives the light coming out of an optical block BO according to a predefined intensity (see figure 5 ). The lower sub-sector SS4 corresponds to the maximum lower angular spacing of the observer with respect to the axis AX where he still perceives the light coming out of this same optical block BO according to a predefined intensity (see figure 5 ).

For example, the first predefined vertical angular extension (of the upper sub-sector SS3 of the vertical angular sector SAV of the lighting device DE of an optical block BO) may be between 5 ° and 25 °, upwards. Also for example, the second predefined vertical angular extension (of the lower sub-sector SS4 of the vertical angular sector SAV of the lighting device DE of an optical block BO) can be between 5 ° and 25 °, downwards.

So, when the photometric function is a fire function of position (or lantern), the first predefined vertical angular extension may be 15 ° upward and the second predefined vertical angular extension may be 15 ° downward.

It will be noted, as illustrated without limitation on the figure 3 , that the transparent facets FTj of each three-dimensional element ET can be inclined relative to each other by an angle θ which is between 105 ° and 125 °. For example, when the photometric function is a position light function (or lantern) or direction change indicator (or flashing), this angle θ may be equal to 114 °.

It will also be noted that at least the opaque facets FOj can be polished on the side of the front face FV, and that at least areas of the rear face FR of the mask M, located behind the transparent facets FTj, can also be polished. These polishes are intended to "burst" or "distribute" the photons in many directions to facilitate obtaining the vertical angular sector SAV associated with the photometric function, especially when the latter is a position light function (or lantern) .

It will also be noted, as illustrated without limitation on the figure 2 that the transparent facets FTj of the three-dimensional elements ET (here belonging to different levels) can extend mutually along lines (here oblique) which intersect each other and where the photons define light bands which intersect. A kind of grid or light grid is thus obtained via the transparent facets FTj.

It will also be noted that each opaque facet FOj may, for example, be coated on the front face FV with a metal layer that is suitable for ensuring its opacity. For example, this metal layer may be aluminum or nickel / chromium.

It will also be noted that each transparent facet FTj may, for example, have a transparency resulting from a laser ablation of the metal layer previously deposited on the entire front face FV, or of a deposit of a savings (or a savings mask) during the metallization phase. It will be understood that in the first alternative, the entire front face FV of the mask M is metallized and then removes this metallization on each facet FTj to be transparent by means of a laser, while in the last alternative is placed a saving (or a savings mask) on each facet FTj to be transparent before the metallization phase, then, once the latter is completed (and therefore once the opaque facets FOj metallized), all savings (or all savings masks) are removed.

It will also be noted, as illustrated without limitation on the figure 2 that each transparent facet FTj of a three-dimensional element ET may, for example, have a general (quasi) triangular shape. This general form here gives the impression that the opaque facets FOj are "open" in their lower part extended by the two transparent facets FTj associated. But the transparent facets FTj of the three-dimensional elements ET can present other general flat polygonal shapes. Moreover, the transparent facets FTj are not necessarily identical from one three-dimensional element ET to the other. So, in the example shown on the figure 2 , the three-dimensional elements AND placed on the same line at a given level have substantially identical FTj transparent facets, but different in size from the transparent facets FTj of the three-dimensional elements AND which are placed on the same line at a higher or lower level. For example, the height of the short side of each transparent facet FTj may increase as the level decreases, to enhance the opening effect of the opaque facets FOj located in the lower levels.

It will also be noted that the angle existing between an opaque facet FOj and an associated transparent facet FTj (which extends it) may possibly vary, for example as a function of the level at which the three-dimensional element ET belongs. This is particularly the case in the example of mask M illustrated on the figure 1 . But this angle could be substantially constant.

It will also be noted that the angle mentioned in the preceding paragraph may be a function of the general angle of inclination of the mask M with respect to the horizontal plane XY and / or the shape of a subpart of the possible reflector RP which is intended to reflect the photons towards three-dimensional and associated elements (and therefore especially to their transparent facets FTj and opaque facets FOj).

It will also be noted that when the lighting device DE is a rear light providing a position light function, it must produce a red light. In this case, the red color may result, for example, from the use of light source (s) SL generating photons whose wavelength is that of white and a mask M having this red color (possibly crystal). This last combination makes it possible to have an extinguished rendering of red color on the transparent facets FTj. But we can also produce a red light using light sources SL generating photons whose wavelength is that of this red color and a mask M having a white color (possibly crystal).

It will also be noted that the use of a reflector RP comprising, as indicated above, predefined sub-parts in order to reflect the photons respectively to three-dimensional AND associated elements (placed at different levels), makes it possible to have a rendering homogeneous at the level of opaque facets FOj while respecting the photometric constraints thanks to the exit of the photons by the transparent facets FTj.

Claims (10)

Lighting device (DE) comprising at least one light source (SL) capable of generating photons and a mask (M) able to let said photons generated at predefined locations, characterized in that said mask (M) comprises a front face (FV), facing outwards, and provided with three-dimensional elements (ET) participating together in a predefined photometric function and each having a general shape diamond point defined by at least two opaque facets (FOj) contiguous and inclined with respect to one another and at least two transparent facets (FTj) contiguous and each extending in an inclined manner, in one of said predefined locations, one of said opaque facets (FOj) towards a opaque facet (FOj) of at least one other neighboring three-dimensional element (ET). Device according to claim 1, characterized in that said three-dimensional elements (ET) are placed relative to each other so that their transparent facets (FTj) together deliver photons in a predefined horizontal angular sector and in a vertical angular sector ( SAV) predefined. Device according to claim 2, characterized in that said predefined vertical angular sector (SAV) is subdivided into an upper subsector (SS3) and a lower subsector (SS4), on the one hand, mutually extending on the other hand, and on the other hand, having an axis (AX) having a predefined direction, and, secondly, respectively having first and second predefined vertical angular extensions. Device according to claim 3, characterized in that said first predefined vertical angular extension is between 5 ° and 25 °, and said second predefined vertical angular extension is between 5 ° and 25 °. Device according to one of claims 1 to 4, characterized in that said transparent facets (FTj) of each three-dimensional element (ET) are inclined relative to each other by an angle of between 105 ° and 125 °. Device according to one of claims 1 to 5, characterized in that at least said opaque facets (FOj) are polished, and in that at least areas of a rear face (FR) of said mask (M), behind said transparent facets (FTj) are polished. Device according to one of claims 1 to 6, characterized in that said transparent facets (FTj) of the three-dimensional elements (ET) extend mutually along intersecting lines and where the photons define intersecting light bands. Device according to one of claims 1 to 7, characterized in that it comprises a reflector (RP) adapted to reflect said photons generated towards a rear face (FR) of the mask (M), opposite to said front face (FV) . Vehicle optical block (BO), characterized in that it comprises at least one lighting device (DE) according to one of the preceding claims. Vehicle, characterized in that it comprises at least one optical block (BO) according to Claim 9 and / or at least one lighting device (DE) according to one of Claims 1 to 8.

Images