Optical device for motor vehicle and motor vehicle comprising the optical device

Abstract

Optical device for motor vehicle and motor vehicle comprising the optical device The invention relates to an optical device (1, 2) for motor vehicle comprising: A transparent protective element (10) comprising an outer face (10.1) and an inner face (10.2); A lighting device, said first lighting device comprising: a light guide comprising a transparent and flexible light guide sheet (12), said light guide sheet (12) comprising an outer surface (12.1) and an inner surface (12.2) opposite the outer surface, said outer surface (12.1) being fixed to the inner face (10.2) of the transparent protective element (10), a light source (13) adapted to inject light emitted by the first light source (13) into a region of the light guide sheet; and An optical unit (14) or a sensor (15) positioned opposite the inner surface (12.2) of the light guide mat (12). FIG. 1.

Description

Title of the invention: Optical device for a motor vehicle and motor vehicle comprising the optical device TECHNICAL FIELD OF THE INVENTION

[0001] One aspect of the present invention relates to an optical device for a motor vehicle comprising a luminous signaling or display device. The luminous device is associated with a light source having a signaling or lighting function or with an optical sensor.

[0002] The invention further relates to a motor vehicle comprising the optical device according to the first aspect of the invention. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] Motor vehicles are generally equipped with lighting devices, intended to illuminate the road, and signaling devices, intended to inform other drivers or pedestrians of the presence of the vehicle. Motor vehicles are further equipped with sensors, used for example to detect obstacles or the presence of other vehicles on the road. The lighting devices having signaling and / or lighting functions and the sensors are part of the optical devices of a motor vehicle.

[0004] In a vehicle according to the state of the art, the lighting devices must perform several functions so as to allow the driver to guide his vehicle safely without endangering other road users. Among the lighting functions it is possible to cite: the dipped beam, the main beam or the fog light. In the same way, the signaling devices must perform several functions, allowing other drivers to identify the position of the motor vehicle as well as its changes of direction or speed. Among the signaling functions it is possible to cite: the daytime running light, the position light, the reversing light, the brake light, the position indicator. More recently, a driving mode indicator has been introduced to be able to signal to other drivers that the vehicle is in autonomous driving mode.

[0005] Each of these functions, also called photometric functions, must comply with the regulations in force in the countries in which the vehicle will be used. The regulations in force may contain requirements for colorimetry, intensity, spatial distribution according to a so-called photometric grid or even visibility ranges of the emitted light.

[0006] Since the volume available on board a motor vehicle is very limited, car manufacturers must now design lighting devices capable of combining several regulated photometric, lighting or signaling functions, which can make these devices very complex and expensive. These constraints can also concern the external appearance of signaling and / or lighting devices such as front or rear headlights.

[0007] For example, in front headlights for motor vehicles according to the state of the art, the implementation of a signaling function such as the daytime running light with a certain shape desired by the manufacturer inevitably places constraints on the implementation of the lighting functions. In other words, it is difficult today to freely choose the appearance of the signaling functions without modifying the appearance of the lighting functions and vice versa.

[0008] Automobile manufacturers encounter similar difficulties when they wish to add, in addition to signaling and lighting functions, display functions, for example for decorative purposes. Here, display functions are understood to mean functions which are not regulated photometric functions. Such display functions may include, for example, the display of a manufacturer's logo or the display of certain animations. It is very complicated today to add display functions to luminous lighting and / or signaling devices while complying with the regulations in force and without adding additional constraints on the appearance of the devices themselves.

[0009] A similar problem exists for other optical devices present in motor vehicles, such as sensors. Indeed, it is not known today how to combine motor vehicle sensors and light devices with a signaling or display function, without disturbing the sensors. Summary of the invention

[0010] To address the problems mentioned above, the invention relates to a lighting assembly for a motor vehicle combining an optical unit performing a signaling and / or lighting function, and / or a sensor, with a flexible and transparent lighting device. Thanks to its characteristics, the lighting device does not impose constraints on the appearance of the optical unit or the sensor included in the lighting assembly according to one aspect of the invention.

[0011] According to a first aspect, the invention relates to a lighting assembly for a motor vehicle comprising: • A transparent protective element comprising an external face and an internal face opposite the external face; • A light device, otherwise called the first light device, comprising: • a light guide comprising a transparent and flexible light guide sheet, said light guide sheet: • comprising an external surface and an internal surface opposite the external surface, said external surface being fixed to the internal face of the transparent protective element; • being configured to guide the light by total internal reflection and to emit the light towards the transparent protective element; • at least one light source adapted to inject light into a region of the light guide sheet; and • an optical unit and / or a sensor positioned opposite the internal surface of the light guide sheet.

[0012] A lighting assembly of a motor vehicle is understood to mean a device comprising at least one element configured to emit light. A lighting assembly may also comprise a sensor.

[0013] An optical unit is understood to mean a device comprising at least one light source configured to perform a photometric function of a motor vehicle. A photometric function will for example be a lighting and / or signaling function visible to a human eye. In the automotive field, this photometric function may comply with the regulations in force in the country where it will be used, it will then be qualified as regulatory. Regulatory photometric functions are for example: • daytime running light (DRL), regulation 087 UNECE, • the position light, regulation 007 UNECE, • the code fire, regulations 112 and 98 UNECE, • the main beam, regulations 98 and 112 UNECE, • the reversing light, regulation 023 UNECE, • the brake light, regulation 007 UNECE, • the direction indicator, regulation 006 UNECE, • the fog light, UNECE regulations 019 and 038, • the regulations may contain requirements for colorimetry, intensity, spatial distribution according to a so-called photometric grid or even visibility ranges of the emitted light.

[0014] An optical unit may also include optical elements such as a lens, an objective or a polarizer.

[0015] For example, the sensor may be a lidar (corresponding in English to “Light detection and ranging”), namely a distance measuring device based on the analysis of the properties of a beam of light returned to its transmitter. Alternatively, the sensor may be a radar, in particular operating at a frequency between between 76 and 81 Gigahertz. The sensor can also be an infrared camera or a camera in the visible spectrum. Alternatively, the sensor can be a combination of at least two of the elements mentioned above.

[0016] The light assembly according to the first aspect of the invention can therefore be used as a front headlight or rear headlight of a vehicle.

[0017] A transparent protective element or "coverlens" according to English terminology means an element transparent to the light emitted or captured by the light assembly. The transparent protective element makes it possible to isolate the light assembly from the external environment, thus protecting its elements.

[0018] The transparent protective element is therefore delimited by an internal face and an external face, the external face being the face closest to the exterior of the vehicle.

[0019] In the same way, the light guide sheet is delimited by an internal surface and an external surface, the external surface being the face closest to the exterior of the vehicle and therefore opposite the internal face of the transparent protective element.

[0020] A light guide sheet is understood to mean a flexible and transparent optical guide element, one of whose dimensions is much smaller than the other two dimensions in space. Here, a flexible guide sheet is considered, the thickness of which, namely the distance separating the external surface and the internal surface of the guide sheet, is at least two orders of magnitude smaller than its dimensions in the plane of the sheet. For example, the guide sheet has a thickness of between 200 and 1000 micrometers and extends over several cm in the plane of the sheet.

[0021] The guide sheet is capable of receiving light rays emitted by the first light source and of returning said light rays towards the transparent protective element in a direction substantially normal to the plane of the sheet. In other words, the light guide sheet is adapted to emit light rays towards the outside of the vehicle.

[0022] In a known manner, the guide sheet has optical decoupling elements making it possible to extract the light propagating inside the guide sheet. For example, the decoupling elements are micro-engravings present in the guide sheet. In the case of the device according to the first aspect of the invention, the rays are therefore emitted towards the transparent protective element and therefore towards the outside of the vehicle.

[0023] According to one aspect of the invention, the optical decoupling elements may be arranged uniformly in the light guide sheet, which gives an illuminated appearance of the entire light guide sheet, or they may be arranged in a grouped manner according to a predefined spatial distribution to form a light pattern. The pattern may be a shape, a symbol or the combination of both.

[0024] The light assembly according to the invention makes it possible to combine a light device, an optical unit and / or a sensor. The light device is fixed to the inner face of the transparent protective element, which therefore has a role as a support element for the flexible and transparent guide sheet. The light device is spatially separated from the optical unit and / or the sensor, which are positioned opposite the inner surface of the light guide sheet. The presence of the light device, having a flexible and transparent emissive surface, does not pose any constraint on the shape or operation of the optical unit or the sensor positioned inside the light assembly.

[0025] For example, the light device may provide a first signaling function, while the optical unit may provide a second signaling function and / or a lighting function. Since the light device does not modify the structure or function of the optical unit, the light assembly according to the invention allows great flexibility in the design of the light assembly for motor vehicles.

[0026] Furthermore, since the light device is completely independent of the optical unit, it can provide display functions. In addition, since the guide sheet has a surface area of ​​up to several tens of square centimeters, it can be used as a screen for displaying animations.

[0027] Due to the flexibility of the light guide sheet, the light device can conform to the shape of the inner face of the transparent protective element, thereby reducing the size of the light device. The transparent protective element also acts as a support element for the light guide sheet.

[0028] Similarly, the light assembly according to the first aspect of the invention makes it possible to combine a sensor and a light device having, for example, a signaling function. Indeed, the light device is configured to emit light rays, in particular towards the inside and the outside of the vehicle. However, the light emission towards the inside of the vehicle, that is to say in the direction of the sensor positioned behind the light device, has very little impact on the sensor, which guarantees proper operation of the latter.

[0029] The light assembly according to the first aspect of the invention therefore makes it possible to add a light emission function to the sensor, while reducing the size of the light assembly present on board a motor vehicle.

[0030] Another aspect of the invention relates to a motor vehicle comprising a light assembly according to the first aspect of the invention.

[0031] In addition to the characteristics which have just been mentioned in the preceding paragraphs, the light assembly according to one aspect of the invention may have one or more additional characteristics among the following, considered individually: dually or in all technically possible combinations: • the light source of the light device has a property corresponding to a first motor vehicle signaling function, said property associated with said first signaling function being the color and / or the intensity of the light emitted by this source; • this allows the light device to be used to perform a regulated signalling function without placing any constraints on the shape or external appearance of the optical unit; • the first signaling function is chosen from a group comprising: position light, daytime running light, brake light, direction indicator and driving mode indicator; • thanks to the characteristics of the flexible and transparent luminous device it is possible to carry out a wide variety of photometric signaling functions; • the light device comprises a plurality of light sources, each light source being configured to inject light into a different region of the light guide sheet; • this arrangement is particularly suitable for a light guide sheet with a large width; it also allows for light animations to be created by switching light sources on or off individually according to a predefined sequence; • the light device comprises at least one light coupling element, the light coupling element being associated with said at least one light source so as to receive the light emitted by said corresponding light source and so as to transmit the received light to a region of the light guide sheet; • the coupling element makes it possible to collect the maximum amount of light emitted by the light source, and therefore to improve the efficiency of the lighting device; • according to an exemplary embodiment of the invention, the light device comprises at least two light coupling elements and at least two light sources, each light source being coupled to a respective light coupling element; furthermore, the light coupling elements are arranged so as to illuminate two different regions of the light guide sheet; for example, the light coupling elements are arranged on the same side of the guide sheet; • for example, the light coupling element is made in one piece with the light guide sheet; • the light guide sheet is fixed to the internal face of the element transparent protective layer using a transparent and flexible adhesive layer, said adhesive layer being positioned between the inner face of the transparent protective element and the outer surface of the light guide sheet; the adhesive layer makes it possible to fix the guide sheet to the internal face of the transparent protective element without altering the properties of the light emitted by the first light source and the second light source; alternatively, the light guide sheet is overmolded onto the transparent protective element using a suitable injection process; Making the outer surface of the light guide sheet equal to or greater than Making the inner surface of the transparent protective member; this allows the light coupling member to be arranged by the edge of the light guide sheet, the coupling member connecting the light guide sheet to the first light source; the optical unit is configured to perform a second motor vehicle signaling function and / or a motor vehicle lighting function; of course, the optical unit and the light device are configured so that the presence of one does not disturb the light propagation or projection of the other when it is in operation; the second signaling function associated with the optical unit is selected from a group comprising: position light, daytime running light, brake light, direction indicator and driving mode indicator and the lighting function associated with the optical unit is chosen from a group comprising: low beam, high beam and fog light; due to the fact that the optical unit is independent of the light device, the optical unit can provide a wide range of photometric functions; the optical unit can comprise a light source of the matrix type of light-emitting diodes; a light source of the light-emitting diode matrix type makes it possible to implement adaptive lighting functions, for example by adapting the emission profile of the light source depending on the presence of other vehicles on the road; the light device of the light assembly presented above is otherwise called the first light device; the light assembly further comprises a second light device, said second light device comprising: a second transparent and flexible light guide comprising a second light guide sheet, said second light guide sheet light : • comprising an outer surface and an inner surface opposite the outer surface, the outer surface of the second light guide sheet being attached to the inner surface of the second light guide sheet; • being configured to guide the light by total internal reflection and to emit the light towards the transparent protective element; • a second light source configured to inject the emitted light into a region of the second light guide sheet, wherein the first and second light devices are arranged such that the first and second guide sheets are at least partially superimposed in the light assembly so as to project light through a common area of ​​the transparent protective element; thanks to the presence of a second light device arranged in contact with the first, it is possible to set up a second signaling or display function in addition to the function provided by the first light device.

[0032] A second aspect of the invention relates to a motor vehicle comprising a light assembly according to the first aspect of the invention. BRIEF DESCRIPTION OF THE FIGURES

[0033] Other advantages and characteristics of the invention will appear on reading the following description, illustrated by the figures in which: • [Fig.l] represents an embodiment of a light assembly according to the first aspect of the invention; • [Fig.2] represents another embodiment of a light assembly according to the first aspect of the invention; • [Fig.3] represents a three-dimensional view of an embodiment of a light assembly according to the first aspect of the invention; • Figures 4 and 5 illustrate two embodiments of a light assembly according to the first aspect of the invention, the light assembly being positioned at the rear of a motor vehicle; • [Fig.6] shows schematically the structure of a light guide sheet; • [Fig.7] illustrates an embodiment of a light guide; • Figures 8 and 9 show an example of a light coupling element coupling a light source to a light guide sheet.

[0034] In the figures, identical elements are identified by identical references. For reasons of readability of the figures, the size scales between elements represented are not respected. DETAILED DESCRIPTION

[0035] Examples of embodiments of a lighting assembly for a motor vehicle according to one aspect of the invention are described in detail below, with reference to the appended drawings. These examples illustrate the characteristics and advantages of the invention. It is however recalled that the invention is not limited to these examples.

[0036] [Fig.l] illustrates an embodiment of a light assembly 1 according to one aspect of the invention.

[0037] The light assembly 1 according to the embodiment illustrated in [Fig.l] comprises: • a transparent protective element 10 delimited by an external face 10.1 and an internal face 10.2 opposite the external face; the transparent protective element is for example made of transparent polycarbonate and protects the light assembly 1 from the external environment while being transparent to light; • a light device 11 comprising a transparent and flexible light guide, said light guide comprising a light guide sheet 12; • a light source 13 configured to inject the emitted light inside the light guide sheet 12; • an optical unit 14 adapted to emit light rays R towards the exterior of the motor vehicle.

[0038] The light guide sheet 12 comprises an outer surface 12.1 and an inner surface 12.2 opposite the outer surface 12.1. The guide sheet 12 is adapted to guide the light by total internal reflection and to emit the light towards the transparent protection element 10 and therefore towards the outside of the vehicle.

[0039] The optical unit 14 is positioned opposite the internal face 12.2 of the light guide sheet 12. The light source 13 and the optical unit 14 are therefore independent and allow the implementation of two different photometric functions. For example, the light source 13 can provide a first signaling function while the optical unit 14 can provide a second signaling function or a lighting function.

[0040] Due to the fact that the light guide associated with the light source 13 is flexible and transparent, no constraints are imposed on the shape of the optical unit 14 providing the second signaling function or the lighting function. This provides great design freedom for automobile manufacturers, who can therefore combine several functions in a single light assembly 1.

[0041] [Fig. 2] illustrates a second embodiment of a light assembly 2 according to a state of the art. In the case shown in [Fig. 2], the light assembly 3 understand: • a transparent protective element 10 delimited by an external face 10.1 and an internal face 10.2 opposite the external face; the transparent protective element is for example made of transparent polycarbonate and protects the light assembly 2 from the external environment while being transparent to light; • a light device 11 comprising a light guide, said light guide comprising a transparent and flexible light guide sheet 12; • a light source 13 configured to inject the emitted light inside the light guide sheet 12; • a sensor 15 adapted to receive light rays R2 coming from outside the vehicle, the sensor 15 being positioned opposite the internal face 12.2 of the light guide sheet 12.

[0042] The sensor 15 is adapted to receive light rays R2 coming from outside the vehicle and passing through the transparent protection element 10 and the transparent light guide sheet 10.

[0043] Due to the fact that the light guide sheet 12 of the light device is configured to emit light towards the transparent protection element 10, the light emitted by the light device does not disturb the sensor 15.

[0044] The sensor 15 can for example be a camera, an infrared camera, a radar, a lidar or even a photodiode.

[0045] According to one embodiment, not illustrated in Figures 1 and 2, the light assembly 1 or 2 may comprise a plurality of light sources, each source being an independent light source. Each source is then configured to inject light into a different region of the light guide sheet 12. In addition, each source may be associated with a different photometric function, the light emitted by each light source having different characteristics. For example, each light source may emit light rays having characteristics corresponding to a different photometric function.

[0046] According to one embodiment, not illustrated in Figures 1 and 2, the light assembly may comprise a second light device, identical to the first light device included in the light assembly described with reference to Figures 1 and 2.

[0047] In particular, the second light device comprises a second light guide comprising a second light guide sheet delimited by an external surface opposite the internal surface. The external surface of the second light guide sheet is fixed to the internal surface of the first light guide sheet, for example by means of a transparent and flexible adhesive layer.

[0048] Thanks to the presence of two light devices each comprising a light guide sheet and a light source, it is possible to increase the display and / or signaling functions provided by the light assembly according to a first aspect of the invention.

[0049] [Fig. 3] illustrates a three-dimensional representation of a light assembly 1 according to an embodiment of the first aspect of the invention. As illustrated in [Fig. 1], the light assembly 1 comprises the light device 11 provided with a light guide comprising a flexible and transparent light guide sheet 12 and a light source (not visible in [Fig. 3]) associated with the light guide and adapted to inject light rays into the guide sheet 12.

[0050] In the light assembly illustrated in [Fig. 3], the light device 11 also comprises a light coupling element (not visible in [Fig. 3]) disposed between the light source and the light guide sheet 12 for transmitting the light emitted by the light source to the sheet 12. An example of the light coupling element will be explained later in the description with supporting figures 6 and 7.

[0051] Here, the sheet 12 and the transparent protective element 10 are held in a frame 15 which grips the peripheral edges of these elements. The frame 15 has grooves forming a housing for the light coupling element and the light source. Thus designed, the frame 15 makes it possible to hide the coupling element and the light source in order to improve the aesthetic appearance of the lighting device.

[0052] The light assembly 1 illustrated in [Fig.3] further comprises an optical unit 14 positioned inside the motor vehicle and facing the inner surface 12.2 of the guide sheet 12. The optical unit 14 is adapted to emit light rays passing through the guide sheet 12 towards the outside of the vehicle.

[0053] [Fig. 3] illustrates how the light emitted by the optical unit 14 passes through the transparent and flexible light guide sheet 12 without the shape or function of the optical unit 14 being modified by the presence of the light device comprising the light guide sheet 12. In other words, the light device comprising the light guide sheet 12 does not have any constraints on the shape or function of the optical unit 14.

[0054] [Fig. 4] illustrates an example of a light assembly 4 comprising an optical unit 14 and used in a rear headlight of a motor vehicle. In the case illustrated in [Fig. 4], the light source has a rear position light function and the optical unit has the function of a brake light and position indicator. [Fig. 4] illustrates in particular the external appearance of the light assembly 4 for three different operating modes of the device.

[0055] The panel 40 illustrates the external appearance of the light assembly 4 when only the light source is lit. In this case, the light device of this assembly 4 appears as a homogeneous luminous surface of constant intensity and typically red in color. To achieve this, the light guide sheet comprises a plurality of light decoupling elements which are distributed uniformly over the entire surface of the sheet. In addition, the light source used is a source emitting red light.

[0056] The panel 41 illustrates the appearance of the device 1 in the event of braking of the vehicle and therefore activation of the optical unit. In this case the light assembly 4 appears as a homogeneous light surface with three parallel bands 41A of constant intensity and a color different from that displayed by the light guide sheet, typically dark red. It is obvious how, thanks to this embodiment of the light assembly 4, it is possible to obtain a particular effect for the stop light signaling function, without this effect being altered by the presence of the position light signaling function in the same light assembly.

[0057] Finally, the panel 42 illustrates the external appearance of the light assembly 4 when the direction indicator is activated by switching on the optical unit. The geometric pattern displayed, the three bands 42A, is the same as for the case of the brake light function, this pattern being associated with the shape of the optical unit. However, in this case, the intensity of the three bands 42A is flashing with a typically yellow or orange color. In this case, the optical unit comprises a plurality of light sources, these sources emitting different colors and being controlled independently.

[0058] The example illustrated in [Fig.4] shows how, by using the light assembly according to one aspect of the invention, it is possible to combine three different signaling functions while leaving a great deal of design freedom concerning the external appearance and shape of the signaling devices.

[0059] [Fig. 5] illustrates an example of a light assembly 5 comprising an optical unit and used in a rear headlight of a motor vehicle. As in the case of [Fig. 4], the light source provides a rear position light function. The optical unit provides a brake light function.

[0060] Panel 50 shows the external appearance of the light assembly when only the light source is switched on to display a homogeneous luminous surface, typically red in color. Panel 51 shows the external appearance of the light assembly during braking of the vehicle when the optical unit is also in operation. In addition to the homogeneous luminous surface, a pattern 51A is now displayed with a constant luminous intensity.

[0061] The examples illustrated in Figures 4 and 5 illustrate how the shape of the first signaling function and that of the second signaling function are completely independent, the lighting device posing no constraint on the appearance of the second light source.

[0062] An example of a light guide used in a light assembly according to one aspect of the invention is illustrated in [Fig. 6]. The light guide as illustrated in [Fig. 6] comprises a transparent and flexible light guide sheet 12 adapted to receive light rays by a light injection edge 114 and to return the light rays in a direction x substantially normal to a surface of the flexible guide sheet which thus extends in a plane yz in [Fig. 6]. The directions x, y and z are defined in relation to the reference frame illustrated in [Fig. 6].

[0063] 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. Here, a flexible guide sheet is considered whose thickness along the x axis, namely the distance between the external surface and the internal surface, is at least two orders of magnitude smaller than its dimensions along the yz plane in which the flexible guide sheet 12 extends. For example, the guide sheet has a thickness along the x axis of between 200 and 1000 micrometers and extends over several cm along the y and z directions.

[0064] The flexible guide sheet 12 may comprise a flexible film 121 at its core comprising the light injection edge 114. The flexible film further comprises a set of microstructures 113 capable of returning the light rays guided in the flexible film 111 outside the flexible guide sheet 12, in particular in one or more directions substantially along the x axis. In the example illustrated in [Fig. 6], the light rays emerge in the +x direction according to the orientation illustrated in the figure. For example, the light rays are emitted towards the outside of the front face of a vehicle.

[0065] The flexible guide sheet 12 may further comprise one or two optional protective layers 122 and 123, which make it possible to mechanically protect the flexible film 111.

[0066] [Fig. 7] illustrates another view of a light device used in a light assembly according to one aspect of the invention. The flexible guide sheet 12, or precisely the flexible film 121, may comprise a mixing zone 111.2 and several regions 111.1, each region comprising a light emission zone provided with light extraction elements capable of returning the light rays guided in the flexible film outside the flexible and transparent guide sheet 12, in particular in one or more directions substantially along the x axis. In a light device used in a light assembly according to one aspect of the invention, the light extracted from the guide sheet 12 is returned towards the transparent protective element 10 and therefore towards the outside of the vehicle.

[0067] The mixing zone 111.2 is arranged upstream of the light emission zone according to the direction of propagation of the light rays within the guide sheet 12. The light injected into the light guide sheet 12 via the edge 114 will be mixed in the light mixing region 111.2 in order to obtain better light homogeneity. The light then propagates in the different regions, or precisely in the light emission zones 111.1 through which the light emerges from the light guide sheet 12 in the x direction. Thus, when a region receives light, the light emission zone reflects light outwards and displays a light pattern.

[0068] By way of example, the light extraction elements 113 may be microstructures 113 etched in the flexible film 111. In the remainder of the description, the microstructures 113 are cited as an example of the light extraction elements 113.

[0069] The light guide according to the embodiment illustrated in [Fig.7] further comprises at least one light coupling element 102.

[0070] A light coupling element 102 comprises several strips 102.1 cut from the guide sheet. For example, it comprises between three and ten strips 102.1. In the example of [Fig.7], the light guide comprises a light coupling element 102 with ten elements 102.1. The coupling element 102 injects light into the guide sheet 12, in particular in the region 111.1.

[0071] It will be noted that during the process of manufacturing the light guide, the strips 102.1 and the light guide sheet 110 are manufactured from a large raw sheet which is sheared on one end to separate the different strips 102.1 along the y axis illustrated in [Fig.7] and thus form the different light injection elements. Thus, the strips 102.1 remain attached to the light guide sheet 12 on one of their ends. By shearing the raw sheet, we mean cutting all the layers included in the raw sheet to form parallel strips constituting the light injection strips 102.1.

[0072] By means of a folding element (not shown in the figures) contained in the light guide, each strip is folded to form a stack as shown in [Fig.8] and [Fig.9].

[0073] Indeed, as illustrated in [Fig.8], each light injection strip 102.1 is composed of: • a main portion 102.12 which is cut from the light guide sheet and extends from the light guide sheet, and • an end portion 102.13 which extends along the z axis.

[0074] The end portion 102.13 is connected to the light guide sheet 110 by means of the main portion 102.12. The main portions 102.12 and the end portion 102.13 are divided by a fold 102.14 at a folding element not shown in [Fig.8]. The end portion 102.13 extends after the fold 102.14. The fold 102.14 is a fold with a non-zero radius of curvature, which allows the light to propagate. [Fig.8] illustrates the end portions 102.13, the main portions 102.12 of the light injection strips 102.1 of a light coupling element 102 as well as the fold 102.14 which separates them. The total length of a light injection waveguide 102.1 is the sum of the length of the main portion 102.12 and the end portion 102.13.

[0075] As illustrated in [Fig.9], the strips 102.1 of a group 102 are folded so that their end portions 102.13 form a stack 124 with thickness E adapted to an emission surface of the light source 20. The thickness E is the sum of the thicknesses e of each strip 102.1 whose end portions 102.13 form the stack 124. The stack 124 comprises an entry surface 124.1 formed by the ends of the end portions 102.13 of each of the light injection elements 102.1 of the group 102.

[0076] The light coupling element 102 is coupled with at least one light source 13 so as to receive the light rays R emitted by said source in each of the light injection elements.

[0077] Since the light injection elements are integral with the light guide sheet, the light rays R will propagate by total internal reflection in the bands e 102.1 of the group 102 so as to bring light to the light guide sheet 12 which is adjacent and attached to the bands 102.1 and which will thus illuminate the region of the light guide sheet 12.

[0078] Although described through a number of examples, variations and embodiments, the display panel, display system and display method according to the various aspects of the invention include various variations, modifications and improvements which will be apparent to those skilled in the art, it being understood that these variations, modifications and improvements are within the scope of the invention.

Claims

Claims

1. A light assembly (1; 2; 4; 5) for a motor vehicle comprising: • A transparent protective element (10) comprising an external face (10.1) and an internal face (10.2) opposite the external face; • A light device (11) comprising: • a light guide comprising a transparent and flexible light guide sheet (12), said light guide sheet (12) comprising an external surface (12.1) and an internal surface (12.2) opposite the external surface, said external surface (12.1) being fixed to the internal face (10.2) of the transparent protective element (10), and being adapted to guide the light by total internal reflection and to emit the light towards the transparent protective element (10); • at least one light source (13) adapted to inject light inside a region of the light guide sheet; • An optical unit (14) and / or a sensor positioned opposite the internal surface (12.2) of the light guide sheet (12).

2. Light assembly (1, 2) according to the preceding claim in which said at least one light source (13) has a property corresponding to a first motor vehicle signaling function, said property associated with said first signaling function being the color and / or the intensity of the light emitted by said at least one light source (13).

3. Lighting assembly (1; 2; 4; 5) according to the preceding claim in which the first signaling function associated with said at least one light source (13) is chosen from a group comprising: position light, daytime running light, brake light, direction indicator and driving mode indicator.

4. Light assembly (1; 2; 4; 5) according to the preceding claim, in wherein the light device comprises a plurality of light sources (13), each light source being configured to inject light into a different region of the light guide sheet (12).

5. A light assembly (1; 2; 4; 5) according to one of the preceding claims, wherein the light device (11) comprises a light coupling element (102), the light coupling element (102) being associated with said at least one light source so as to receive the light emitted by said corresponding light source and so as to transmit the received light to a region of the light guide sheet (12).

6. Light assembly (1; 2; 4; 5) according to the preceding claim, wherein said light coupling element (102) is integral with the light guide sheet.

7. Light assembly (1; 2; 4; 5) according to one of the preceding claims in which the light guide sheet (12) is fixed to the internal face (10.2) of the transparent protective element (10) using a transparent and flexible adhesive layer, said adhesive layer being positioned between the internal face of the transparent protective element and the external surface (12.1) of the light guide sheet (12).

8. Light assembly (1; 2; 4; 5) according to one of the preceding claims in which the area of ​​the outer surface (12.1) of the light guide sheet (12) is equal to or greater than the area of ​​the inner face (10.2) of the transparent protective element (10).

9. Light assembly (1; 4; 5) according to one of the preceding claims, wherein the optical unit (14) is configured to perform a second motor vehicle signaling function and / or a motor vehicle lighting function.

10. Lighting assembly (1; 4; 5) according to the preceding claim in which: • the second signaling function associated with the optical unit (14) is chosen from a group comprising: position light, daytime running light, brake light, direction indicator and driving mode indicator and • the lighting function associated with the optical unit is chosen from a group comprising: dipped beam, main beam and fog lights.

11. A light assembly (1; 2; 4; 5) according to one of the preceding claims, wherein the light device (11) is a first light device and wherein the light assembly further comprises a second light device, said second light device comprising: • a second transparent and flexible light guide comprising a second light guide sheet, said second light guide sheet: • comprising an outer surface and an inner surface opposite the outer surface, the outer surface of the second light guide sheet being attached to the inner surface of the second light guide sheet; • being configured to guide the light by total internal reflection and to emit the light towards the transparent protective element;• a second light source configured to inject the emitted light into a region of the second light guide sheet in which the first and second light devices are arranged such that the first and second guide sheets are at least partially superimposed in the light assembly so as to project light through a common area of ​​the transparent protective element.;

12. Motor vehicle comprising a light assembly (1; 2) according to one of the preceding claims.

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