Lighting device having a lighting module arranged in front of an illumination module

Abstract

The invention relates to a lighting device (300) for a motor vehicle, comprising at least one illumination module (301.1; 301.2) suitable for projecting light rays in order to carry out a lighting function, a lighting module (100; 200) and a control element (340). The lighting module is at least partially transparent and is arranged such that light rays emitted by the illumination module pass through it, and the control element is suitable for activating the lighting module when the at least one illumination module is deactivated.

Description

[0001] Description

[0002] Title: LIGHTING DEVICE WITH A LIGHTING MODULE ARRANGED IN FRONT OF A LIGHTING MODULE

[0003] The present invention relates to the field of lighting devices comprising one or more lighting modules, in particular for motor vehicle headlights. The invention applies in particular, but not exclusively, to the external appearance of such headlights, in particular when the vehicle is traveling during the day.

[0004] Lighting devices such as headlights generally have a plurality of lighting functions performed by one or more modules. The following lighting functions are known in particular:

[0005] - a low beam type lighting function, or LB, for “Low Beam” in English;

[0006] - a high beam type lighting function, or HB, for “High Beam” in English, which can be carried out by the same lighting module as that in charge of the LB function, or by a separate module;

[0007] - a daytime signaling function, also called DRL, for “Daytime Running Light” in English, generally carried out by a light module separate from the LB / HB module;

[0008] - a signaling function of the “position light” type, or PL for “Position Lighting” in English, which can be performed by the light module which performs the DRL function, or by another light module.

[0009] The “signature” is the external appearance of the lighting device, which depends on the respective arrangement of the light modules, their number and their respective shapes. The signature is particularly observable when all the modules of the lighting device are activated.

[0010] Such a signature may be perceived differently when driving at night and during the day. Indeed, at night, the module(s) that perform the lighting functions such as LB and HB are visible to an outside observer. A complete signature is thus obtained. However, during the day, these lighting functions are generally not activated, which induces one or more black areas in the signature of the lighting device. The signature of the lighting device is incomplete and different from the night signature for an observer located outside the vehicle.

[0011] There is therefore a need to harmonize the signature of lighting devices for motor vehicles between daytime and nighttime driving, while providing a robust, easy-to-integrate and inexpensive solution.

[0012] The present invention improves the situation.

[0013] To this end, a first aspect of the invention relates to a lighting device for a motor vehicle, comprising at least one lighting module capable of projecting light rays to perform a lighting function, a lighting module and a control element. The lighting module is at least partially transparent and is arranged so as to be traversed by light rays emitted by the lighting module and the control element is capable of activating the lighting module when the at least one lighting module is deactivated.

[0014] The use of an activated light module when the at least one lighting module is deactivated makes it possible to harmonize the signature of the lighting device between night and day driving situations. In addition, the light module being at least partially transparent, it allows the lighting function to be performed by the lighting module when the light module is not activated.

[0015] According to non-limiting embodiments, said at least one lighting module may be capable of performing a dipped beam lighting function and / or a high beam lighting function.

[0016] Such functions are generally deactivated during the day, and the modules performing them are specifically suited to creating dark areas in the signature of the lighting device. When a single lighting module is capable of performing both functions, the space requirement associated with performing these functions is limited in the lighting device.

[0017] According to non-limiting embodiments, the lighting device may comprise a first lighting module capable of performing a dipped beam lighting function and a second lighting module capable of performing a high beam lighting function, the lighting module being arranged so as to be traversed by the light rays coming from the first lighting module and / or the second lighting module.

[0018] Thus, the lighting device may comprise two lighting modules, and the lighting module may be capable of hiding the dark areas associated with at least one of these two lighting modules.

[0019] A single light module can also be shared across two lighting modules, which limits the costs and size of the lighting device according to the invention.

[0020] According to non-limiting embodiments, the light module may be capable of emitting light rays according to at least one light pattern, the light module being arranged so that said at least one light pattern is opposite an optical surface of the at least one lighting module.

[0021] Thus, the light pattern can superimpose the optical surface of the at least one lighting module. In particular, the light pattern can have the same shape as the optical surface of the at least one lighting module, which makes it possible to harmonize the signature of the lighting device with great precision.

[0022] According to non-limiting embodiments, the light module may be arranged inside a lens of an optical system of the lighting module.

[0023] The light module is thus mechanically protected and is not exposed to the outside of the light device. According to non-limiting embodiments, the light module can be arranged on an external glass of the light device.

[0024] This makes it easier to install the light module.

[0025] According to a first non-limiting embodiment, the light module may comprise:

[0026] - a light guide comprising an at least partially transparent guide sheet, the guide sheet being capable of receiving light rays via at least one light injection edge of said guide sheet and of returning the light rays in a direction substantially normal locally to a surface of the guide sheet according to at least one light pattern, the light guide further comprising at least one light injection element capable of receiving light and distributing the light in the guide sheet;

[0027] - at least one light source capable of injecting light into said at least one light injection element.

[0028] The control element may be capable of activating said at least one light source when the lighting module is deactivated.

[0029] Thus, the light module is of the type with a guide sheet, for example with a flexible guide sheet, which is inexpensive, easy to manufacture, and easy to integrate. In addition, such a solution is not very sensitive to environmental conditions such as humidity and temperature.

[0030] The term "flexible" means that the guide sheet is capable of being curved without being damaged. Thus, such a guide sheet can be placed on a non-planar support and adopt its shape without being damaged. In particular, when the light module comprising the flexible guide sheet is placed opposite a lighting module, the flexible guide sheet can be curved according to the curvature of an optical projection surface of the lighting module. In particular, the flexible guide sheet can be arranged convexly with a radius of curvature directed towards the interior of the motor vehicle when the lighting device is mounted in or on said motor vehicle.

[0031] Additionally, according to the first non-limiting embodiment, the lighting device may comprise a first lighting module capable of performing a dipped beam lighting function and a second lighting module capable of performing a main beam lighting function, the lighting module may comprise a single light guide, a first pattern being etched in a first part of the guide sheet of the single light guide and a second pattern being etched in a second part of the guide sheet of the single light guide, the first pattern may be arranged opposite a first optical projection surface of the first lighting module and the second pattern may be arranged opposite a second optical projection surface of the second lighting module.

[0032] This reduces the size and cost associated with the light module, with a single injection element and a source to illuminate two patterns opposite two separate lighting modules.

[0033] Additionally, the single light guide may comprise the guide sheet, a first light injection element and a second light injection element, the first light injection element may be arranged to inject light into a first section of the light injection edge of the guide sheet and the second light injection element may be arranged to inject light into a second section of the light injection edge of the guide sheet, the first portion of the guide sheet being located opposite the first section of the light injection edge and the second portion of the guide sheet being located opposite the second section of the light injection edge.

[0034] Such embodiments advantageously make it possible to selectively control the lighting of the first and second light zones. It is thus possible to illuminate only according to one or the other of the patterns, in particular when only one of the lighting modules is deactivated. According to second and third non-limiting embodiments, the light module may comprise an at least partially transparent substrate, an emissive layer comprising an electroluminescent material comprised between a first electrode and a second electrode, the first electrode being comprised between the transparent substrate and the emissive layer, the control element may be capable of controlling a voltage source capable of applying a voltage between the first electrode and the second electrode, so that the emissive layer emits light rays towards the outside of the light module.

[0035] Thus, the light module can be an at least partially transparent screen that is only activated when the lighting module is deactivated. The space requirement associated with the lighting device is thus reduced compared to a solution with a light guide.

[0036] Additionally, according to the second and third non-limiting embodiments, the first electrode, the second electrode and the emissive layer may each have a thickness of less than 10 micrometers, in particular less than 1 micrometer.

[0037] Such thicknesses allow high transparency of the light module, which allows the lighting function to be performed by the lighting module, while reducing the size associated with the lighting device. Such thicknesses can in particular be obtained by an atomic thin film deposition process.

[0038] According to non-limiting embodiments, the light module may further comprise a first transport layer and a second transport layer, the first transport layer being comprised between the emissive layer and the first electrode and the second transport layer being comprised between the emissive layer and the second electrode.

[0039] It is thus made possible to facilitate the recombination of electrons and holes in the emissive layer so as to emit light rays towards the outside of the light module. In the second and third non-limiting embodiments, the light module may further comprise an at least partially transparent protective layer, for example made of glass, the second electrode being comprised between the protective layer and the emissive layer.

[0040] This way, the light module is mechanically protected.

[0041] According to the second non-limiting embodiment, the electroluminescent material may be an inorganic electroluminescent material, in particular an inorganic electroluminescent material comprising manganese-doped zinc sulfide.

[0042] Such a material has better tolerance to temperature variations than an organic material.

[0043] Manganese-doped zinc sulfide produces yellow or green light and operates in a temperature range of -100°C to +105°C.

[0044] According to the third non-limiting embodiment, the electroluminescent material may be an organic electroluminescent material, in particular an organic electroluminescent polymer.

[0045] The light module can therefore be an organic light-emitting diode, called OLED, for “Organic Light Emitting Diode” in English, or a pixelated OLED screen.

[0046] According to non-limiting embodiments, the lighting device may further comprise a signaling module capable of performing a daytime signaling function, in which the control unit is capable of controlling the signaling module, and, upon activation of the daytime signaling function, the control unit may be configured to activate the lighting module. Indeed, such a signaling function being activated during the day, the lighting module is then activated when the lighting functions are deactivated. Harmonization of the signature of the lighting device is thus facilitated.

[0047] Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended drawings in which:

[0048] [Fig 1 a] illustrates a light guide of a light module of a light device for a motor vehicle, according to a first non-limiting embodiment of the invention;

[0049] [Fig 1 b] illustrates a front view of a light module of a light device for a motor vehicle, according to the first non-limiting embodiment of the invention;

[0050] [Fig 1 c] illustrates a three-dimensional view of a light module of a light device for a motor vehicle, according to the first non-limiting embodiment of the invention;

[0051] [Fig 2] illustrates a light module of a light device for a motor vehicle, according to second and third non-limiting embodiments of the invention;

[0052] [Fig 3] illustrates a lighting device for a motor vehicle, according to non-limiting embodiments of the invention;

[0053] [Fig 4] illustrates a first example of a light module of a light device for a motor vehicle, according to the first non-limiting embodiment of the invention;

[0054] [Fig 5] illustrates a second example of a light module of a light device for a motor vehicle, according to the first non-limiting embodiment of the invention;

[0055] [Fig 6] illustrates a third example of a light module of a light device for a motor vehicle, according to the first non-limiting embodiment of the invention. The description focuses on the characteristics which distinguish the light device and the light module from those known in the state of the art.

[0056] Figure 1a shows a light guide 105 of a light module of a light device for a motor vehicle, according to a first non-limiting embodiment of the invention.

[0057] The light guide 105 comprises a guide sheet 110 capable of receiving light rays via a light injection edge 114 and of returning the light rays in a direction Z substantially normal to a surface of the guide sheet which thus extends in an XY plane in FIG. 1 a.

[0058] A guide sheet is understood to mean an optical guide element one of whose dimensions is much smaller than the other two dimensions in space, for example smaller by one or more orders of magnitude. As illustrated in FIG. 1a, a guide sheet is considered here whose thickness along the Z axis is at least two orders of magnitude smaller than its dimensions along the XY plane in which the guide sheet 110 extends. Such a guide sheet can advantageously be flexible, which facilitates its integration into a lighting device. In the following, a flexible guide sheet 110 is considered for illustrative purposes.

[0059] The guide sheet 110 may comprise a film 111, which may advantageously be flexible, at its core comprising at least one light injection slice 114, being capable of guiding the light rays in a global direction X, and comprising a set of microstructures 113 capable of returning the light rays guided in the film 111 outside the guide sheet 110, in particular in one or more directions substantially along the Z axis.

[0060] The film 111 may be a substrate film made of polycarbonate, PC, polymethyl methacrylate, PMMA, thermoplastic polyurethane, TUP, or polyethylene terephthalate, PET. The film 111 may have a thickness, i.e. a dimension along the Z axis, of between 12 and 1000 micrometers. More specifically, the thickness of the film 111 may be between 50 and 1000 micrometers, for example between 200 and 500 micrometers. Alternatively, it is the guide sheet 110 which has a thickness of between 200 and 1000 micrometers.

[0061] The aforementioned materials, combined with a low thickness as described above, make it possible to obtain a flexible film 111. Other materials may be provided for the composition of the flexible film 111. However, it is preferable according to the invention to provide deformable and transparent materials.

[0062] A thin coating of microstructures 113 may be applied to one of the faces of the film 111, or be integrated into the film 111. The coating of microstructures 113 may in particular have a thickness along the Z axis of less than 20 micrometers.

[0063] Such microstructures 113 may have a general bump shape, on which the light rays are reflected in a direction substantially along the Z axis. Such microstructures 113 may be capable of causing the light rays exiting the film 111 to form a light pattern. For this purpose, the microstructures 113 may be etched by ultraviolet printing, so as to reflect the light rays injected into the injection wafer 114 through the surface of the film 111 according to the desired pattern. For example, the microstructures may be distributed to form a light pattern of a given shape with homogeneous light over the entire light pattern thus formed.

[0064] Microstructures 113 are understood to mean structures, or irregularities of the film 111, whose dimensions are less than a few micrometers. The microstructures thus also cover nanometric structures. Such sizes of microstructures 113 make it possible to ensure high transparency of the film 111. In particular, a transparency of the order of 97% can be obtained in practice by the use of microstructures 113. The light module according to the first embodiment of the invention, comprising the light guide 105, is at least partially transparent, that is to say that it lets through at least some of the light rays which reach the guide sheet. For example, the light module may have a transparency greater than 50%, preferably greater than 70%, or even greater than 90%.Advantageously, the microstructures 113 can be distributed along the X axis so that a linear density of microstructures 113 is proportional to the distance from the light injection slice 114 through which the light rays injected by an injection element 120 of the light guide 105 are received.

[0065] In other words, the further the microstructures 113 are from the light injection edge 114, the more densely they are grouped. Such a distribution advantageously makes it possible to ensure a homogeneous distribution along the X axis of the light intensity of the pattern emitted by the guide sheet 110.

[0066] The guide sheet 110 may further comprise one or two optional protective layers 112.1 and 112.2, which make it possible to mechanically protect the film 111. In addition, at least one of the protective layers 112.1 and 112.2 may comprise an anti-UV treatment, making it possible to protect the film 111 against UV rays, once the microstructures 113 have been etched. Without such UV protection, the pattern projected by the guide sheet 110 is likely to degrade over time, in particular when exposed to sunlight.

[0067] The film 111 and the protective layers 112.1 and 112.2 are shown spaced apart in FIG. 1 a, for illustrative purposes only. It will be understood, however, that the protective layers 112.1 and 112.2 may be attached to the film 111, in particular by lamination.

[0068] Since the guide sheet 110 can be flexible, it is not necessarily included in a plane but can be curved, depending on the position in which it is placed and the mechanical constraints applied to it.

[0069] The light guide 105 illustrated in Figure 1 a also comprises a light injection element 120, comprising a set of injection sheets described with reference to Figures 1 b and 1 c, the light injection element 120 being able to distribute the light in the guide sheet 110 at different positions along the Y axis, along the light injection edge 114. The light is injected, at each position along the Y axis, in a direction substantially parallel to the X axis. The light injection element 120 comprises an entry surface 121 of rectangular or square section in Figure 1 a. However, the light injection element 120 may have an entry surface having a section of different shape.

[0070] In Figure 1 a, the light injection element 120 is shown with an exit surface 122 extending in the direction Y and placed opposite the light injection edge 114. It will be understood from reading the description of Figures 1 b and 1 c that the exit surface 122 and the light injection edge 114 are preferably merged, the film 111 and the set of injection sheets forming a single piece.

[0071] The input surface 121 is capable of receiving light rays from a light source external to the light guide 105 and not shown in FIG. 1a. The light injection element 120 is capable of guiding the light longitudinally along the Y axis by distributing it on the output surface 122. The distribution of light by the output surface 122 will be better understood in the light of the description of FIGS. 1b and 1c.

[0072] Figure 1b shows a light module 100 of a light device according to the first embodiment of the invention. The light module 100 comprises a light guide 105 with an injection element 120 and a guide sheet 110, and a light source 130.

[0073] With reference to Figure 1 c, the injection element 120 may comprise a plurality of injection sheets 123.1, 123.2 and 123.3, capable of receiving light from the source 130 via the entry surface 121 and of guiding the light to sets 124.1, 124.2 and 124.3 of positions along the distinct Y axis. As shown in Figures 1b and 1c, the injection sheets 123.1, 123.2 and 123.3 may be made of the same material and have the same thickness as the film 111 of the guide sheet 110. Thus, the light guide 105 may be obtained by a roll-to-roll, or R2R, manufacturing procedure, during which the film 111 and the injection sheets 123.1, 123.2 and 123.3 are obtained from the same roll of film, which may be flexible, the injection sheets 123.1, 123.2 and 123.3 being cut at different positions in Y, in a cutting direction substantially parallel to the X direction. The injection sheets 123.1, 123.2 and 123.3 thus obtained are preferably flexible and can be folded as shown in Figure 1c. Each injection sheet 123.1, 123.2 and 123.3 can be cut to respective lengths so that once folded, its end forms with the ends of the other injection sheets the injection surface 121, as illustrated in Figure 1c.

[0074] An injection element 120 with three injection layers 123.1, 123.2 and 123.3 has been shown in FIGS. 1 b and 1 c, for illustrative purposes only. The injection element 120 may however comprise any set of injection layers comprising at least two injection layers.

[0075] No restrictions are attached to the light source 130. The light source 130 may be capable of generating light in a range of wavelengths. Such a range may be centered around a visible color, in order to generate colored light, for example blue, red or green. Alternatively, the light source 130 may emit light rays over the entire range of wavelengths visible to the human eye, so as to generate white light. A very restricted range of wavelengths may be produced by a laser-type light source 130.

[0076] The light source 130 may be controlled by a control element not shown in FIGS. 1 b and 1 c, but described later with reference to FIGS. 3 to 6.

[0077] Alternatively, the light source 130 is not arranged directly opposite the entry surface 121 of the injection element 120, but the light module 100 according to the first embodiment further comprises an optical fiber placed between the source 130 and the injection element 120, which makes it possible to offset the source 130 relative to the light guide 105.

[0078] The injection element 120 presented thus makes it possible to inject light at different longitudinal positions along the Y axis of the light injection slice 114. Each longitudinal position of the injection slice 114 can correspond to a guide line of the film 111, capable of guiding the light along the X axis along such a guide line.

[0079] Such an association of a light guide 105 comprising a guide sheet 110 and an injection element 120, and a source 130 thus makes it possible to display a pattern by emitting light mainly in the Z direction, by a surface that is at least partially transparent and with good surface homogeneity. In addition, when the guide sheet is flexible 110, the integration of the light module 100 into equipment is facilitated.

[0080] In practice, such a light module 100 according to the first embodiment makes it possible to emit light with a brightness of between 100 and 1000 Candelas per square meter, with a light extraction efficiency which can vary between 25% and 80%.

[0081] Details of the structure and arrangement of elements 105, 110, 120, and 130 are further described in the international patent application published under number WO2011130715A2.

[0082] The term “pattern” means any predefined spatial distribution or distribution of the light intensity emitted by the light module 100. In particular, reference is made here to a two-dimensional or one-dimensional pattern.

[0083] A pattern may thus comprise a homogeneous distribution of light across the entire light module. The pattern may also be a two-dimensional shape or symbol obtained by contrast between the light intensities of different positions in the XY plane of the guide sheet 110. The pattern may also comprise several shapes or symbols.

[0084] A light module of a vehicle light device according to the first embodiment of the invention comprises:

[0085] - a light guide 105 comprising a guide sheet, such as the guide sheet 110 illustrated in FIG. 1 a, capable of returning light according to at least one light pattern, and at least one light injection element such as the injection element 120 described with reference to FIGS. 1 a, 1 b and 1 c; and - at least one light source such as the light source 130 previously described with reference to FIGS. 1 b and 1 c, capable of injecting light into said at least one injection element.

[0086] Figure 2 illustrates a light module 200 of a light device for a vehicle, according to second and third non-limiting embodiments of the invention.

[0087] The light module 200, unlike the light guide light module 100, is a screen activated by applying a potential difference to an emissive layer composed of an electroluminescent material.

[0088] The light module 200 is also at least partially transparent, thanks in particular to the properties of the layers which compose it and which are described below.

[0089] The second and third embodiments differ primarily in the electroluminescent emissive layer that is used.

[0090] According to the second embodiment, the emissive layer is formed from an inorganic electroluminescent phosphor, while in the third embodiment the emissive layer is formed from an organic electroluminescent material.

[0091] In the second and third embodiments, the light module 200 comprises:

[0092] - a substrate 201 of an at least partially transparent material, for example glass. Such a material can be chosen because it allows high transparency;

[0093] - a first electrode 203, for example a cathode, connected to a voltage source controlled by a control element 240;

[0094] - a hole transport layer 204, or HTL, for “Hole Transport Layer”, in English, in contact with the cathode 203;

[0095] - an emissive layer 205 comprising an electroluminescent material;

[0096] - an electron transport layer 206, or ETL, for “Electron Transport Layer” in English, in contact with a second electrode 207; - a second electrode 207, in particular an anode 207. Note that the anode and the cathode can be reversed in the stack of layers, connected to the voltage source controlled by the control element 240;

[0097] - a protective layer 209, in an at least partially transparent material, preferably glass. Such a material can be chosen because it allows high transparency.

[0098] The electron transport layer 206 may comprise a material doped with electrons, that is to say it has excess electrons, promoting the transfer of electrons in the emissive layer 205. Symmetrically, the hole transport layer 206 may comprise a material having a defect in electrons, or doped with holes, thus promoting the creation of holes in the emissive layer and thus promoting recombination in the emissive layer 205 leading to the emission of photons. The holes and electrons combine in the emissive layer, leading to the emission of photons whose properties depend in particular on the electroluminescent material of the emissive layer. Such a principle is well known and is not described further in the present description.

[0099] The emissive layer 205 can thus emit photons when a voltage greater than a threshold voltage is applied to the electrodes 203 and 207.

[0100] The light module 200 according to the second and third embodiments may also optionally comprise:

[0101] - an ionic barrier layer 202 between the substrate 201 and the first electrode 203;

[0102] - a layer of optical index matching material 208, comprised between the protective layer 209 and the second electrode 207, capable of allowing the light rays coming from the emissive layer 205 to pass through the protective layer 209. In particular, the light rays emitted by the emissive layer 205 can be bent towards a main emission direction which is preferentially along the Z axis, therefore perpendicular to the surface of the protective layer 209. The properties and the thickness of the layer of optical index matching material 208 can depend on the optical index of the protective layer 209.

[0103] In Figure 2, the first electrode 203 comprises several conductive elements arranged at different positions in X and extending longitudinally along the Y axis. Similarly, the second electrode 207 may comprise several conductive elements arranged at different positions in Y and extending longitudinally along the X axis. The control element 240 can thus apply a voltage to specific positions of the emissive layer, by selecting an element of the first electrode to select a position in X and by selecting an element of the second electrode 207 to select a position in Y. It is thus made possible to control the light module in a pixelated manner. The light module 200 can thus form a pixelated screen. However, such an embodiment is optional.

[0104] Indeed, according to the invention, the first and second electrodes 203 and 207 may each comprise a single planar element extending continuously in different positions in X and Y, so as to apply a voltage to a set of positions in X and Y of the emissive layer, these positions forming a light pattern. Such a light pattern may have a regular shape such as a square, a rectangle, a diamond or other, or may have a more complex shape, comprising curves for example. To produce such a pattern, the emissive layer 205 may have a given shape in the XY plane corresponding to the desired light pattern. Thus, at certain locations of the light module, the emissive layer 205 may be absent between the layers 204 and 206, and the application of an electrical voltage to these locations thus produces no light rays, making it possible to produce light patterns.

[0105] At least partial transparency of the light module 200 is permitted:

[0106] - by the material used for the cover layer 209 and the substrate layer 201, which are preferably made of glass. The layers 201 to 209 are thus not constrained on their thickness, along the Z axis. The thickness of each layer 201 and 209 is however preferably less than 2 mm; - by the respective thicknesses of the electrodes 203 and 207, and of the layers 202, 204 to 206 and 208, which are less than 10 micrometers, preferably less than 1 micrometer.

[0107] The elements common to the second and third embodiments have been described above.

[0108] In the second embodiment, the emissive layer 205 comprises an inorganic electroluminescent material, for example an inorganic phosphor. For example, the emissive layer 205 may comprise zinc sulfide, denoted ZnS, doped manganese, denoted ZnS:Mn. The ZnS:Mn material allows the emission of photons of wavelengths corresponding to a yellow or green color. Other inorganic electroluminescent materials may be provided according to the second embodiment. For example, the emissive layer 205 may comprise Indium Gallium Nitride, InGaN, which comprises Gallium Nitride GaN and Indium Nitride, InN. The wavelength of the light emitted by such a material may vary from the ultraviolet range to orange, depending on an Indium to Gallium ratio.According to other examples, the emissive layer 205 may comprise quantum dots based on Cadmium Selenium (CdSe), Copper-Indium (Culn), Indium Phosphorus (InP) and / or Lead Selenium (PbSe). The color of the emitted light may vary, in particular across all wavelengths in the visible range, depending on the size of the quantum dot. By way of illustration, a 6 nanometer quantum dot is capable of emitting red light rays while a 2 nanometer quantum dot is capable of emitting blue light rays.

[0109] Electrodes 203 and 207 may be made of indium tin oxide, or ITO. However, there are no restrictions on the material of electrodes 203 and 207.

[0110] No restriction is also attached to the material of the transport layers 204 and 206, which may be made of antimony-doped tin oxide, also referred to as ATO. Preferably, some of the layers may be produced by an atomic thin film deposition manufacturing process, also called ALD for "Atomic Layer Deposition" in English, which makes it possible to increase the transparency of the light module 200. In particular, such a manufacturing process may be used to manufacture the emissive layer 205, but also, optionally, to manufacture the transport layers 204 and 206, as well as for the ion barrier layer 202 and the optical index matching layer 208.

[0111] According to such a manufacturing method, the deposited material does not form a continuous layer but is distributed in the XY plane according to a certain granularity, which increases the transparency of the layer and therefore of the light module 200.

[0112] It is thus made possible to obtain high transparencies of the light module 200, in particular greater than 60%, or even 70%, for example equal to 80%.

[0113] The bias voltage for activating the emission of photons in the emissive layer may be several hundred volts, for example equal to 195V. The control element 240 can thus control the voltage source supplying the electrodes 203 and 207 to apply such a voltage or to apply no voltage. It is thus made possible to activate and deactivate the light module 200 by the control element 240. The voltage is preferably applied at high frequency, in particular at a frequency between 400 Hz and 1 kHz.

[0114] This gives an operating power of the order of a few Watts, notably between 3W and 12W, for a high brightness of the order of several hundred Candelas per square meter, which can reach up to 1300 Cd / m 2 .

[0115] The light module according to the second embodiment also has the advantage of operating in a wide temperature range, in particular between -100°C and +105°C. Alternatively, according to the third non-limiting embodiment of the invention, the emissive layer 205 may comprise an organic electroluminescent material, for example an organic polymer.

[0116] The light module 200 then forms an organic light-emitting diode screen, called OLED, for “Organic Light Emitting Diode” in English.

[0117] Layers 201 to 204 and 206 to 209 may be identical to those described with reference to the second embodiment.

[0118] According to a fourth non-limiting embodiment of the invention, the light module 200 according to the second and third embodiments further comprises a light guide 105 as presented in the first embodiment:

[0119] - in place of the substrate 201, or arranged against the substrate 201; and / or

[0120] - in place of the cover layer 209, or arranged against the cover layer 209.

[0121] This makes it possible to create distinct light patterns, which can be activated selectively or cumulatively in order to superimpose the light patterns.

[0122] According to a non-limiting embodiment, a light guide 105 can be arranged in place of the substrate 201, or against the substrate 201, the first light guide 105 comprising a first pattern etched in the guide sheet 110, and the emissive layer 205 is distributed according to a second pattern, distinct from the first pattern.

[0123] According to another non-limiting embodiment, a light guide 105 may be arranged in place of the cover layer 209, or against the cover layer 209, the first light guide 105 comprising a first pattern etched in the guide sheet 110, and the emissive layer 205 is distributed according to a second pattern, distinct from the first pattern.

[0124] According to yet another non-limiting embodiment, a first light guide 105 is arranged in place of the substrate 201, or against the substrate 201, the first light guide 105 comprising a first pattern etched in its guide sheet 110, the emissive layer 205 is distributed according to a second pattern, and a second light guide 105 is arranged in place of the cover layer 209, or against the cover layer 209, the second light guide 105 comprising a third pattern etched in its guide sheet, the first, second and third patterns being distinct.

[0125] Figure 3 illustrates a light device 300 according to non-limiting embodiments of the invention.

[0126] The light device 300 according to the invention comprises at least one light module according to the first, second, third or fourth embodiment. Exemplary embodiments of the light module 100 according to the first embodiment will be described with reference to FIGS. 4, 5 and 6, which describe light modules 400, 500 and 600 respectively. The light module 100 according to the first embodiment may thus be a light module 400 according to a first example, a light module 500 according to a second example or a light module 600 according to a third example. The light module 200 corresponds to the second and third embodiments.The fourth embodiment may combine the light module 200 according to the second and third embodiments, with one or more of the examples of light modules 400, 500 and 600 described below, arranged in place of the substrate 201, or arranged against the substrate 201; and / or arranged in place of the cover layer 209, or arranged against the cover layer 209.

[0127] Thus, the light module shown in Figure 3 encompasses all embodiments and is referenced 100, 200.

[0128] As will be better understood, the light device 300 may comprise several light modules 100, 200.

[0129] The lighting device 300 further comprises at least one lighting module 301.1 or 301.2 capable of projecting light rays towards the outside of the lighting device 300 to perform at least one lighting function. Such a lighting function may for example be a low beam function LB or a high beam function HB. Alternatively, the at least one lighting module 301.1 or 301.2 is controllable, for example by a control element 340, and can be controlled to perform two different lighting functions, such as the LB and HB functions. No restriction is attached to the technology associated with the lighting module. No restriction is in particular attached to the light source of the at least one lighting module 301.1 or 301.2, which may be a source comprising one or more light elements, such as one or more LEDs.The light source of the lighting module may be a matrix source, including a matrix of DMD-type micro-mirrors, a matrix of LEDs, or any other matrix source.

[0130] The lighting device 300 may optionally comprise one or more signaling modules 302.1, 302.2 and 302.3, capable of emitting light rays towards the outside of the lighting device to perform a signaling function. The signaling module may for example be capable of performing a PL position light function or a DRL daytime signaling function. In addition, the at least one signaling module 302.1, 302.2 and / or 302.3 may be capable of performing both PL position light and DRL daytime signaling functions, only the light intensity emitted by the signaling module being able to vary between the two functions. Such a variation in light intensity may be obtained by activating / deactivating light sources of the signaling module, or by supplying the light source(s) with pulse width modulation, by varying the duty cycle.

[0131] The lighting device 300 for a motor vehicle is preferably a motor vehicle headlight, for example a motor vehicle front headlight.

[0132] No restriction is attached to the number of lighting modules, light modules 100, 200 and signaling modules that the light device 300 comprises, nor to their respective shapes and arrangements, which form the signature of the light device 300. The light device 300 according to the invention comprises:

[0133] - at least one lighting module 301.1 or 301.2; - at least one light module 100, 200 as described previously;

[0134] - at least one control element 340;

[0135] - optionally, at least one signaling module.

[0136] According to the invention, the light module 100, 200 is at least partially transparent as previously described and is arranged so as to be crossed by light rays emitted by the at least one lighting module 301.1 or

[0137] 301.2. Preferably, the light module 100, 200 is capable of emitting light according to at least one given pattern, the given pattern having the same shape as an optical projection system of the at least one lighting module 301.1 or

[0138] 301.2.

[0139] Thus, by activating the light module 100, 200 when the at least one lighting module 301.1 or 301.2 is deactivated, it is made possible to homogenize the appearance of the light device between day and night, in particular in order to homogenize a signature of the light device as will be better understood upon reading what follows. The control element 340 can thus activate the light module 100, 200 when the at least one lighting module 301.1 or 301.2 opposite which it is placed is deactivated.

[0140] The light module 100, 200 can be arranged inside a lens of an optical system of at least one lighting module 301.1 or 301.2.

[0141] According to non-limiting embodiments, the lighting device 300 comprises a housing and an external glass, which forms a glass for closing the housing, the at least one lighting module being arranged inside the internal volume created by the housing and the external glass so that at least part of the light rays that it projects pass through the external glass.

[0142] The light module 100, 200 may be arranged on one of the faces of the external glass of the light device opposite the optical system of the at least one lighting module 301.1 or 301.2. The light module 100, 200 may advantageously be arranged on the internal face of the external glass, which makes it possible to ensure protection of the light module 100, 200 against attacks from the external environment. The light module 100, 200 may also be arranged on the external face of the external glass, in particular when the structure of the light module 100, 200 makes it possible to resist the aforementioned attacks.

[0143] In the particular example shown in Figure 3, the lighting device 300 comprises:

[0144] - a first lighting module 301.1 and a second lighting module 301.2. For example, the first lighting module 301.1 can perform a low beam lighting function LB while the second lighting module 301.2 can perform a high beam lighting function HB;

[0145] - a first signaling module 302.1, in two upper and lower parts, a second signaling module 302.2, in two upper and lower parts, and a third signaling module 302.3, in two upper and lower parts. Each signaling module 302.1, 302.2 or 302.3 is capable of emitting light rays towards the outside of the light device to perform a signaling function. Each signaling module can perform a signaling function of its own, or alternatively, the signaling modules 302.1, 302.2 and 302.3 can perform the same signaling function(s), and thus be controlled together, for example by the control element 340;

[0146] - a light module 100, 200 covering the two signaling modules 301.1 and 301.2, capable of displaying a first light pattern opposite the first lighting module 301.1 and a second light pattern opposite the second lighting module 301.2. Alternatively, the lighting device comprises two light modules 100, 200, a first light module 100, 200 capable of being crossed by light rays from the first lighting module 301.1 and a second light module 100, 200 capable of being crossed by light rays from the second lighting module 301.2.

[0147] The control element 340 may be capable of controlling the activation and deactivation of all the modules, i.e. the lighting module(s), the light module(s), and the optional signaling module(s). In this case, the control element integrates the functionalities of the control element 240 previously described according to the second and third embodiments. The control element 340 may control the activation and deactivation of each module as a function of control signals, received for example by a central control module of the motor vehicle, such as an electronic control unit, of the ECU type for “Electronic Control Unit” in English.

[0148] The control element 340 may comprise a processor configured to communicate unidirectionally or bidirectionally, via one or more buses or via a wired connection, with a memory such as a “Random Access Memory” type memory, RAM, or a “Read Only Memory” type memory, ROM, or any other type of memory (Flash, EEPROM, etc.). Alternatively, the memory comprises several memories of the aforementioned types. Preferably, the memory is a non-volatile memory. The processor is capable of executing instructions, stored in the memory, controlling the modules of the lighting device 300 according to control signals. Alternatively, the processor may be replaced by a microcontroller designed and configured to implement the control of the modules according to the control signals received.

[0149] Alternatively, each module among the light, lighting and signaling modules includes a dedicated control element.

[0150] According to the invention, the control element 340 is capable of activating the light module(s) 100, 200 opposite a lighting module which is deactivated. The signature of the lighting device 100, which is constituted by the shapes of the signaling and lighting modules, and by their respective arrangements, is thus homogeneous whether the lighting module(s) are activated or not.

[0151] Thus, an external observer does not see a dark area at the lighting module when the latter is deactivated, as is generally the case during the day. The invention thus makes it possible to homogenize the signature of the lighting device 300.

[0152] Thus, according to the second, third and fourth embodiments, at least one light module 200 is capable of being crossed by the light rays coming from the lighting module 301.1 and / or the lighting module 301.2. When the lighting device 300 comprises a single light module 200, the emissive layer 205 can form a first pattern arranged opposite the lighting module 301.1 and a second pattern arranged opposite the lighting module 301.2.

[0153] When the light device 300 comprises two light modules 200, a first light module 200 comprises an emissive layer 205 forming a first light pattern arranged opposite the first lighting module 301.1 and a second light module 200 comprises an emissive layer 205 forming a second light pattern arranged opposite the second lighting module 301.2.

[0154] When the lighting modules have optical surfaces of different shapes, the light patterns of the light module(s) 200 vary so as to be identical to the respective optical surfaces of the lighting modules that they cover. It is thus made possible to homogenize complex signatures between the day and night periods.

[0155] Several exemplary embodiments are also possible with at least one light module 100 according to the first embodiment. These examples are described below with reference to figures 4, 5 and 6.

[0156] Figure 4 shows a first example of a light module 400 of a light device according to the first embodiment of the invention.

[0157] The light module 400 comprises a light guide 405 comprising a guide sheet 410 and an injection element 420, and a light source 430, similar to the light guide 105 and the light source 130 of the light module 100 previously described.

[0158] The guide sheet 410 is etched so as to return the light rays injected by the injection element 420 according to a light pattern 450, following activation of the light source 430, by the control element 340.

[0159] The pattern 450 is arranged opposite an optical projection surface of a lighting module. The pattern 450 may further be shaped to overlap with the optical projection surface of the lighting module. The pattern 450 may thus have the same shape as a projection in the plane of the guide sheet, of the optical projection surface of the lighting module.

[0160] It is thus made possible to illuminate the pattern 450 by activating the source 430, when the lighting module, on which the light module 400 is placed, is deactivated. Thus, an external observer does not see a dark area at the lighting module when the latter is deactivated, as is the case during the day. The invention thus makes it possible to homogenize the signature of the lighting device comprising a light module 400 arranged on a lighting module.

[0161] The light module 400 can for example be used in the example of FIG. 3, by being arranged opposite the lighting module 301.1 or the lighting module 301.2. Alternatively, the lighting device 300 comprises a first light module identical to the light module 400 arranged opposite the first lighting module 301.1, and a second light module identical to the light module 400 arranged opposite the second lighting module 301.2.

[0162] Thus, several light modules 400 according to the first embodiment can be advantageously used in a light device comprising several lighting modules. When the lighting modules have optical surfaces of different shapes, the patterns 450 of the light modules 400 can be identical to the respective optical surfaces of the lighting modules that they cover. It is thus made possible to homogenize complex signatures between the day and night periods.

[0163] Advantageously, the light source 430 is controlled by the control element 340 previously described. The control element 340 can also control the lighting module opposite which the light module 400 is placed. Thus, the control element 340 is able to activate the light source 430 when it deactivates the lighting module.

[0164] In the example of Figure 3, the control element 340 can activate a first light module 400 arranged opposite the first lighting module 301.1, when the first lighting module 301.1 is deactivated, and the control element 340 can activate a second light module 400 arranged opposite the second lighting module 301.2, when the second lighting module 301.1 is deactivated.

[0165] Alternatively, with reference to Figures 5 and 6, two variant embodiments of the first embodiment are presented, in which a single light module 500 or 600 according to the first embodiment can be arranged opposite at least two lighting modules of a light device.

[0166] Figure 5 illustrates a second example of a light module 500 of a lighting device according to the first embodiment of the invention, which is a variant of the light module 400 previously described.

[0167] According to this variant, the light module 500 comprises a light guide 505 comprising a guide sheet 510 and an injection element 520, and a light source 530 similar to the light guide 105 and to the light source 130 of the light module 100 previously described with reference to FIGS. 1 a to 1 c.

[0168] The guide sheet 510 is etched so as to return the light rays injected by the injection element 520 according to a first pattern 550.1 and according to a second pattern 550.2, following activation of the light source 530.

[0169] The first pattern 550.1 is arranged opposite a first optical projection surface of a first lighting module and the second pattern 550.2 is arranged opposite a second optical projection surface of a second lighting module. The first and second patterns 550.1 and 550.2 may further be shaped to overlap with the optical projection surfaces of the first and second lighting modules. The first and second patterns 550.1 and 550.2 may thus have the same shapes as projections in the plane of the guide sheet 510, of the optical projection surfaces of the lighting modules.

[0170] It is thus made possible to illuminate according to the light patterns 550.1 and 550.2 by activating the source 530, when the first lighting module and / or the second lighting module, on which the light module 500 is placed, is deactivated. Thus, an external observer does not see a dark area at the level of the lighting modules when at least one of the lighting modules is deactivated, as is generally the case during the day. The invention thus makes it possible to homogenize the signature of the lighting device comprising a light module 500 arranged on several lighting modules, by using a single light guide 505 and a single light source 530. The size and costs are thus reduced.

[0171] The light module 500 can for example be used in the example of figure 3, by being arranged opposite the lighting modules 301.1 and 301.2.

[0172] Thus, a single light module 500 can be advantageously used in a light device comprising several lighting modules. When the lighting modules have optical surfaces of different shapes, the patterns 550.1 and 550.2 have different shapes so as to be identical to the respective optical surfaces of the lighting modules that they cover. It is thus made possible to homogenize complex signatures between the day and night periods.

[0173] Advantageously, the light source 530 is controlled by the control element 340 previously described. The control element 340 can also control the lighting modules opposite which the light module 500 is placed. Thus, the control element 340 is able to activate the light source 530 when it deactivates at least one of the lighting modules of the lighting device.

[0174] In the example of Figure 3, the control element 340 can activate the light module 500 arranged opposite the first lighting module 301.1 and the second lighting module 301.2, when the first lighting module 301.1 is deactivated, when the second lighting module 301.1 is deactivated or when the first and second lighting modules 301.1 and 301.2 are deactivated. Figure 6 illustrates a light module 600 according to the first embodiment of the invention, which is a variant of the light modules 400 and 500 previously described.

[0175] According to this variant, the light module 600 comprises a light guide 605 comprising a guide sheet 610, a first injection element 620.1 and a second injection element 620.2, and a first light source 630.1 and a second light source 630.2. These elements are similar to the light guide 105 and to the light source 130 of the light module 100 according to the first embodiment previously described with reference to FIGS. 1 a to 1 c.

[0176] The guide sheet 610 is etched according to a first pattern 650.1 located in a first part of the guide sheet 610, and a second pattern 650.2 located in a second part of the guide sheet 610.

[0177] The first light source 630.1 is capable of injecting light into the first injection element 620.1 which is itself capable of injecting, or distributing, the light into the first part of the guide sheet so as to illuminate according to the first light pattern 650.1. For this purpose, the first injection element

[0178] 620.1 is opposite a first section of the light injection edge 114 of the guide sheet 610.

[0179] The second light source 630.2 is capable of injecting light into the second injection element 620.2 which is itself capable of injecting, or distributing, the light into the second part of the guide sheet 610 so as to illuminate according to the second pattern 650.2. For this purpose, the second injection element

[0180] 620.2 is opposite a second section of the injection section 114 of the guide sheet 610, distinct from the first section.

[0181] In the lighting device, the first pattern 650.1 may be arranged opposite a first optical projection surface of a first lighting module and the second pattern 650.2 may be arranged opposite a second optical projection surface of a second lighting module. The first and second patterns 650.1 and 650.2 may further be shaped to overlap with the optical projection surfaces of the first and second lighting modules. The light patterns 650.1 and 650.2 may thus have the same shapes as projections in the plane of the guide sheet 610, of the optical projection surfaces of the lighting modules.

[0182] It is thus possible to illuminate according to the patterns 650.1 and 650.2 by selectively activating the sources 630.1 and 630.2. When the first lighting module is deactivated, the first light source 630.1 can be activated. When the second lighting module is deactivated, the second light source 630.2 can be activated. Thus, the sources 630.1 and 630.2 can be controlled separately, for example by the control element 340.

[0183] Alternatively, the control element 340 simultaneously activates the sources 630.1 and 630.2, and the light patterns 650.1 and 650.2 are thus displayed when at least one of the first and second lighting modules is deactivated.

[0184] Thus, an external observer does not see a dark area at the lighting modules when at least one of the lighting modules is deactivated, as is generally the case during the day. The invention thus makes it possible to harmonize the signature of the lighting device comprising a light module 600 arranged on several lighting modules, by using a single light guide 605, and by making it possible to selectively illuminate the first and second patterns 650.1 and 650.2.

[0185] The light module 600 can for example be used in the example of figure 3, by being arranged opposite the lighting modules 301.1 and 301.2.

[0186] Thus, a single light module 600 can be advantageously used in a light device comprising several lighting modules. When the lighting modules have optical projection surfaces of different shapes, the first and second patterns 650.1 and 650.2 have different shapes so as to be identical to the respective optical surfaces of the lighting modules that they cover. It is thus made possible to harmonize complex signatures between the day and night periods. Advantageously, the light sources 630.1 and 630.2 are controlled by the control element 340 previously described. The control element 340 can also control the lighting modules opposite which the light module 600 is placed. Thus, the control element 340 is able to selectively activate the light sources 630.1 and 630.2 when it deactivates at least one of the lighting modules of the light device.

[0187] In the example of Figure 3, the control element 340 activates the light source 630.1 so as to emit light according to the first light pattern 650.1 arranged opposite the first lighting module 301.1 when the first lighting module 301.1 is deactivated, and activates the light source 630.2 so as to emit light according to the second light pattern 650.2 arranged opposite the second lighting module 301.2 when the second lighting module 301.2 is deactivated.

[0188] In the first, second, third and fourth embodiments previously described, the pattern(s) of the light module 100, 200 may be controlled depending on the activation of one of the signaling modules.

[0189] The control element 340 can in particular control the light module(s) 100, 200, the lighting module(s), but also one or more signaling modules, such as those shown in FIG. 3. In particular, the control element 340 can advantageously activate the light source(s) of the light module 100, 200 when the DRL daytime signaling function is activated on at least one of the signaling modules responsible for this signaling function. Such a function being activated during the day, it is thus ensured that the light sources of the light modules are activated during the day, which makes it possible to homogenize the signature of the lighting device 300 between daytime and nighttime driving situations.

Claims

Demands 1. Lighting device (300) for a motor vehicle, comprising at least one lighting module (301.1; 301.2) capable of projecting light beams to perform a lighting function, a light module (100; 200; 400; 500; 600) and a control element (240; 340); wherein the light module is at least partially transparent and is arranged so as to be traversed by light beams emitted by the lighting module and wherein the control element is capable of activating the light module when said at least one lighting module is deactivated.

2. Lighting device according to claim 1, wherein said at least one lighting module (301.1; 301.2) is capable of performing a low beam lighting function and / or a high beam lighting function.

3. Lighting device according to claim 2, comprising a first lighting module (301.1) capable of performing a low beam lighting function and a second lighting module (301.2) capable of performing a high beam lighting function, said lighting module (100; 200; 400; 500; 600) being arranged so as to be traversed by the light rays from the first lighting module and / or the second lighting module.

4. A lighting device according to any one of the preceding claims, wherein the lighting module (100; 200; 400; 500; 600) is capable of emitting light beams according to at least one lighting pattern (450; 550.1; 550.2; 650.1; 650.2), the lighting module being arranged so that said at least one lighting pattern is opposite an optical surface of at least one lighting module (301.1; 301.2). A lighting device according to any one of the preceding claims, wherein the light module (100; 200; 400; 500; 600) is arranged inside a lens of an optical system of at least one lighting module (301.1; 301.2). A lighting device according to any one of claims 1 to 4, wherein the light module (100; 200; 400; 500; 600) is arranged on an external lens of the lighting device (300). A lighting device according to any one of the preceding claims, wherein the light module (100; 400; 500; 600) comprises: - a light guide (105; 405; 505; 605) comprising a guiding sheet (110; 410; 510; 610) at least partially transparent, the guiding sheet being capable of receiving light rays through at least one light injection slice (114) of said guiding sheet and of reflecting the light rays in a direction substantially normal locally to a surface of the guiding sheet according to at least one light pattern, the light guide further comprising at least one light injection element (120; 420; 520; 620.1; 620.2) capable of receiving light and distributing the light in the guiding sheet; - at least one light source (130; 430; 530; 630.1; 630.2) capable of injecting light into said at least one light injection element; wherein the control element is capable of activating said at least one light source when the at least one lighting module (301.1; 301.2) is deactivated. Lighting device according to claims 3 and 7, comprising a first lighting module (301.1) capable of performing a light illumination function of crossing and a second lighting module (301.2) capable of performing a high beam lighting function, in which the light module (500) comprises a single light guide (505), a first pattern (550.1) being engraved in a first part of the guide mat (510) of the single light guide and a second pattern (550.2) being engraved in a second part of the guide mat of the single light guide, in which the first pattern is arranged opposite a first optical projection surface of the first lighting module (301.1) and in which the second pattern is arranged opposite a second optical projection surface of the second lighting module (301.2).A lighting device according to any one of claims 1 to 6, wherein the lighting module (200) comprises a substrate layer (201) that is at least partially transparent, an emissive layer (205) comprising an electroluminescent material situated between a first electrode (203) and a second electrode (207), the first electrode being situated between the substrate layer and the emissive layer, wherein the control element (240; 340) is capable of controlling a voltage source capable of applying a voltage between the first and second electrodes, such that the emissive layer emits light rays outwards from the lighting module. A lighting device according to claim 9, wherein the first electrode (203), the second electrode (207), and the emissive layer (205) each have a thickness of less than 10 micrometers, in particular less than 1 micrometer. A lighting device according to any one of claims 9 and 10, wherein the light module (200) further comprises a protective layer (209) that is at least partially transparent, for example, made of glass, the second electrode (207) being located between the protective layer and the emitting layer (205). A lighting device according to any one of claims 9 to 11, wherein the electroluminescent material is an inorganic electroluminescent material, in particular an inorganic electroluminescent material comprising manganese-doped zinc sulfide. A lighting device according to any one of claims 9 to 12, wherein the electroluminescent material is an organic electroluminescent material, in particular an organic electroluminescent polymer.

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