Lighting and signaling device for a motor vehicle.

Abstract

Title: Lighting and signaling device for a motor vehicle. The main object of the present invention is a lighting and signaling device (1) comprising at least one light module (4), including a main light source (3) capable of generating a light beam (A) along a longitudinal optical axis, and an optical element (2) through which the light beam (A) is projected, characterized in that the optical element (2) has a first portion (201) intended to be transverse to the light beam and a second portion (202) arranged in line with the first portion so as to be outside the path of the light beam, the lighting and signaling device further comprising a controllable liquid crystal display (18) attached to the optical element (2). Figure 1.

Description

Title of the invention: Lighting and signaling device for a motor vehicle.

[0001] The invention relates to the field of lighting and / or light signaling in the automotive field.

[0002] The field of lighting and / or light signaling for motor vehicles is subject to regulations requiring that each motor vehicle be equipped with lights fulfilling specific safety functions, including signal lights, dipped headlights, and main beam headlights. Signal lights are generally used to communicate information to other road users, without providing any additional road illumination function useful to the driver, such as turn signals or daytime running lights (also known as DRLs). Dipped headlights allow the driver of a motor vehicle to be seen by other road users and to see the roadway clearly up to 30 meters ahead, without dazzling other road users.High beams, on the other hand, allow the driver to see the road clearly up to 100 meters, but can dazzle other road users, and should only be used outside built-up areas and when there is no other road user in front of the vehicle.

[0003] In order to compact the means of lighting of a motor vehicle, it is sought to group within the same projector the different means enabling the implementation of these signaling functions and these lighting functions, and it may in particular be aimed by the car manufacturers or by the equipment suppliers to have a common optical element for each of these functions, for example in the form of a transparent or translucent screen closing the housing of the projector and from which the light rays emerge forming one or the other of the lighting or signaling beams.

[0004] In this context of a common optical element, it is also desirable to have an equal extent of the illuminated surface from one function to another, particularly for reasons of aesthetics and visual identity of the lighting devices. However, this is complicated by the different characteristics of the lighting and / or signaling functions, with, on the one hand, the directional nature that a lighting beam must maintain and, on the other hand, the diffuse nature of a signaling beam. The presence of diffusing means to generate this beam of Signage can interfere with the propagation of rays intended to form a regulatory lighting beam.

[0005] Furthermore, the design of lighting devices must take into account particular constraints relating to the architecture of these lighting devices where several optoelectronic components must be arranged inside a housing taking into account the cooling requirements of the parts and / or the reduction of the number of parts and / or the limitation of the overall size.

[0006] In this context, the main object of the present invention is a lighting and signaling device comprising at least one light module and one optical element, said light module having a main light source capable of being driven to participate in generating a light beam along a longitudinal optical axis, said light beam being capable of being projected through the optical element, remarkable in that the optical element has a first portion intended to be across the light beam and a second portion arranged in the extension of the first portion so as to be outside the path of the light beam, the lighting and signaling device further comprising an additional light source arranged opposite the second portion, said second portion being configured to guide the light emitted by said additional light source towards the first portion,said lighting and signaling device being also notable in that the lighting and signaling device comprises a controllable liquid crystal display affixed to the first portion of the optical element, the controllable liquid crystal display being capable of assuming different diffusion states, including at least one beam projection state in which the controllable liquid crystal display is transparent and a signal beam emission state in which the controllable liquid crystal display is at least partially diffusing.

[0007] Such a lighting and signaling device can be installed on a vehicle for use as signal lights, dipped headlights and / or main beam headlights for example and thus allow the lighting or signaling beams to be generated on the same display surface, without the presence of the signal lights interfering with the regulatory operation of the main beam headlights or dipped headlights capable of illuminating the road of the vehicle equipped with this lighting and signaling device.

[0008] In the lighting and signaling device according to the invention, the main light source and the light module are configured to participate in generating, when the main light source is activated, a beam of light projected towards the optical element. Such a beam of light is used to produce the low beam and / or the high beam. More specifically, the main light source and the light module are configured to generate a light beam intended to pass through an optical block formed by the controllable liquid crystal display and the optical element. This light beam is capable of forming either a lighting beam or a signaling beam, depending on the diffusion state of the controllable liquid crystal display.

[0009] The optical element is configured to serve as a light guide for light rays propagating within it, from an entrance face opposite which the additional light source, separate from the main light source, is positioned, to an exit face that is the same as the face through which the lighting beam exits the lighting and signaling device.This provides an optical element that allows the implementation, with the same output face, of two distinct lighting functions via the activation of two separate light sources.

[0010] Furthermore, the device is configured such that a controllable liquid crystal display is positioned in the path of the rays emitted by the main light source and the light module, opposite a portion of the optical element, so that these rays successively pass through the controllable liquid crystal display and said portion of the optical element, or said portion of the optical element and the controllable liquid crystal display, depending on their respective positions. In this way, the lighting function implemented by activating the main light source is optimized.

[0011] The realization via a single optical element of a lighting function, with an associated controllable liquid crystal screen, and of a signaling function is made possible here by the specific shape of the optical element which comprises different portions among which a first portion, or main portion, which is the portion previously mentioned and crossed by the rays which also pass through the screen, and a second portion, or reflection portion, which extends the first portion outside the path of these rays, where appropriate by bypassing the controllable liquid crystal screen when the latter is interposed between the light module and the first portion of the optical element.

[0012] The main light source and the light module, as well as the controllable liquid crystal display and the first portion of the optical element, are configured to generate the lighting beam. The rays emitted from the light module propagate through the lighting and signaling device towards the controllable liquid crystal display and then encounter the first portion of the optical element, propagating directly mainly along a longitudinal optical axis.

[0013] The additional light source and the optical element as a whole are configured to generate the signaling beam, this signaling beam This can also result from the combination of beams emitted respectively by the main light source, whose flux may be reduced, and by the additional source, with the liquid crystal display in diffusing mode. Rays emitted by the additional light source enter the optical element directly at a specific area of ​​the second portion forming an entrance face of the optical element, and these light rays propagate within a light guide formed by the second portion of the optical element, for example by successive total internal reflections, until they reach the first portion, where means on board this first portion and / or on the liquid crystal display allow the refraction of the rays outside the first portion of the optical element, towards the outside of the lighting and signaling device.In particular, ray refraction can be generated via prior reflection of the rays by the liquid crystal screen when it is in diffusing mode and placed against the inner face of the first portion of the optical element.

[0014] The portions of the optical element can thus be distinguished according to the optical function in which they participate. The rays propagating within the second portion of the optical element are distinguished by the fact that they do so in an area of ​​the lighting and signaling device that is not traversed by the rays emitted by the light module. In this case, the rays propagating within the second portion of the optical element bypass the controllable liquid crystal display, following the shape of the second portion.

[0015] The first portion of the optical element thus has the dual function of participating in the lighting function and participating in the signaling function, while the second portion of the optical element only has the function of moving the entry face of the rays emitted by the additional light source away from the first portion and therefore from the area in which the controllable liquid crystal screen is located, to facilitate the integration of this additional light source into the lighting and signaling device.

[0016] The controllable liquid crystal display is affixed to this optical element to form an optical block which can strongly diffuse the passage of the lighting beam or which can, on the contrary, weakly diffuse the passage of the lighting beam through the optical element.

[0017] Furthermore, "transparent" means that the controllable liquid crystal display is able to allow light beams to pass through itself without generating significant disturbance of said light beams, for example other than Fresnel reflections when passing through the controllable liquid crystal display.

[0018] Furthermore, the states of the controllable liquid crystal screen can be defined according to the diffusion veil, or Haze index, presented by said controllable liquid crystal screen. For example, in the projection state, the controllable liquid crystal display exhibits a low haze, for example, less than 6%. Advantageously, the haze of the controllable liquid crystal display is approximately 3% when said display is in the projection state.

[0019] Conversely, in the emission state of a signaling beam, the controllable liquid crystal display exhibits a high diffusion haze, for example, greater than 90%. Advantageously, the diffusion haze of the controllable liquid crystal display is approximately 98% when said display is in the emission state.

[0020] According to an optional feature of the invention, the additional light source is arranged opposite a slice of the second portion of the optical element, said slice forming an entrance face arranged opposite the first portion of the optical element.

[0021] According to an optional feature of the invention, the controllable liquid crystal display is arranged between the light module and the optical element so that, when the optical block is transparent as a whole, the beam of light generated by the light module is made to pass successively through the controllable liquid crystal display and through the optical element.

[0022] It follows from the above that a good distinction of the respective functions of the two portions of the optical element is established.

[0023] For optical reasons, the optical element is arranged so that the first portion is positioned in the path of the illumination beam. In this context, and in particular to allow good diffusion of the beam over this entire first portion of the optical element, visible to observers, the controllable liquid crystal display is placed against one face of the first portion of the optical element and can, if necessary, be interposed between the light module and the first portion of the optical element.

[0024] Furthermore, for mechanical reasons, the optical element is extended beyond the path of the light beam. This extension allows it to bypass the controllable liquid crystal display and to position the entrance face of the optical element, intended to be opposite the additional light source, in an area where space is limited and where optimal positioning of the additional light source is possible. For example, it is then easier to integrate cooling means into the additional light source than if this additional light source were positioned opposite a slice of the first portion of the optical element, in an area where the controllable liquid crystal display is already present.

[0025] The invention may include one or more features which are described below, these features being able to be taken alone or in combination with other features.

[0026] According to an optional feature of the invention, the main light source and the additional light source are powered simultaneously or separately. In other words, to perform the lighting function, at least the main light source is activated, while to perform the signaling function, at least the additional light source is activated.

[0027] According to an optional feature of the invention, the first portion of the optical element has an inner face facing inwards towards the lighting and signaling device and an outer face opposite said inner face and facing outwards towards the vehicle. The outer face of the first portion is said to face outwards towards the lighting and signaling device insofar as it faces outwards from the vehicle when the lighting and signaling device is mounted on the latter, this outer face thus forming the face visible to observers outside the vehicle.

[0028] According to an optional feature of the invention, the additional light source is installed opposite the second portion arranged opposite the first portion of the optical element.

[0029] The second portion extends in continuity with the first portion, with a junction zone, which may in particular consist of an angled portion. This junction zone is formed at one end of the first portion.

[0030] According to an optional feature of the invention, the lighting and signaling device comprises one or more second portions configured to extend the first portion on several of its sides, adjacent or opposite. This allows for the installation of several additional light sources opposite one of the second portions and enables light to penetrate the first portion from different directions. The aim is thus to improve the uniformity of the signaling function for an observer viewing the first portion from outside the vehicle, and / or to provide a more powerful signaling function.

[0031] According to an optional feature of the invention, the first portion comprises, opposite its junction with the second portion, a peripheral edge connecting the inner face to the outer face. It is noteworthy, according to this optional feature, that the first portion comprises a peripheral edge that delimits the extent of this first portion opposite the junction zone. This peripheral edge may be straight or convex. The first portion is thus extended on only one side, to allow the arrival of light rays emitted by the additional light source. After propagation in the second portion, bypassing the controllable liquid crystal display. In other words, the second portion extends the first portion only on one side, allowing it to bypass the liquid crystal display while minimizing the amount of material required to create the optical element. This results in an asymmetrical shape of the optical element with respect to a longitudinal optical axis, corresponding to the optical axis of the light module, on which the first portion of the optical element is approximately centered.

[0032] The lighting and signaling device may in particular include a housing configured to house the components of said device, the housing having an opening through which the lighting and signaling beams are intended to exit and opposite which the first portion of the optical element is positioned.

[0033] According to an optional feature of the invention, the optical element is positioned so that the first portion of the optical element is disposed through said opening. Where applicable, the first portion of the optical element contributes to forming one of the walls of the housing, and in particular a front wall.

[0034] According to an optional feature of the invention, the second portion of the optical element is arranged along a side wall of the housing. In other words, the housing may include a front wall, in which is formed the opening that is covered by the first portion of the optical element, and at least one side wall that together with said front wall defines a housing for the light module. The optical element is configured so that the first portion extends substantially parallel to the front wall and so that the second portion extends along another wall. This wall, along which the second portion extends, may include means for holding the second portion of the optical element in position.

[0035] According to an optional feature of the invention, the first portion and the second portion form a single-piece optical element. By single-piece, it is understood that the assembly thus formed cannot be disassembled without breaking the first portion and / or the second portion. Such a single-piece optical element can, in particular, be obtained by an injection molding operation using a suitable material. Alternatively, the two portions can be bonded to each other, in particular with an adhesive having an optical index close, within + / -10%, to the optical index of each of the two portions. In any case, the two portions are advantageously made of the same material, or at the very least of materials whose optical indices are close, again within + / -10%, to each other.

[0036] In other words, the first portion and the second portion extend continuously with a junction zone between them which helps to form the optical element and to perform the function associated with the optical element, and which is therefore carried out in a material allowing the propagation of light rays within it.

[0037] According to an optional feature of the invention, the portions, in particular the first and second portions, are made in one piece and of the same material. In particular, the material used is transparent or translucent, so as to allow the propagation of light rays within it, and it has an optical index that allows, when the optical element is positioned in the housing of the lighting and signaling device and surrounded by air, propagation by successive total internal reflections of the light rays. By way of example, the material may be polymethyl methacrylate (PMMA) or polycarbonate (PC).

[0038] According to an optional feature of the invention, the optical element comprises an angled portion connecting the first portion to the second portion. The first and second portions extend in different directions, and the presence of an angled portion allows these two portions to be connected without hindering the propagation of light rays by successive total internal reflections within the light guide formed by the successive portions of the optical element.

[0039] According to an optional feature of the invention, the lighting and signaling device includes a control element for the controllable liquid crystal display configured to electrically supply the controllable liquid crystal display so that the controllable liquid crystal display switches from a defined projection state to a defined emission state of a signaling beam and vice versa, depending on a change in the power supply. Under the effect of power supply to the controllable liquid crystal display, and more particularly power supply to the polymer matrix via the electrodes, the liquid crystals embedded in the polymer matrix all align themselves parallel to the direction of the electric current flowing through the polymer matrix, that is, perpendicular to the transparent walls of the display.In such a configuration, the light beam is able to pass through the controllable liquid crystal display without being deflected by the liquid crystals, which are arranged in the main direction of propagation of the light beam, so as to form a regulatory lighting beam.

[0040] According to another embodiment of the invention, the liquid crystals are naturally oriented so as to allow the light beam to pass through the controllable liquid crystal display without power supply. In this embodiment of the invention, under the effect of power supply to the controllable liquid crystal display, and more particularly power supply to the polymer matrix via the electrodes, the liquid crystals embedded in the polymer matrix are all oriented randomly, so as to diffuse the light beam when it passes through the controllable liquid crystal display.

[0041] According to an optional feature of the invention, the control element is electrically connected to each of the electrodes of the controllable liquid crystal display.

[0042] According to an optional feature of the invention, the control member is configured to activate and / or control the additional light source. In one of the possible embodiments of the invention, the advantageous feature whereby the additional light source is located away from the first portion of the optical element is thus utilized, insofar as this additional light source can be positioned, depending on the elongation dimension given to the second portion of the optical element, in an area of ​​the device with space to also position the control member.

[0043] According to an optional feature of the invention, the additional light source is arranged on a support element that is common to said additional light source and to at least one other electronic or optical component of the lighting and signaling device. In one of the possible embodiments of the invention, the advantageous feature whereby the additional light source is located away from the first portion of the optical element is thus utilized, insofar as this additional light source can be positioned on a support, for example, fixed to a housing of the lighting and signaling device, which also serves as a support for electronic components, such as, for example, the control unit of the controllable liquid crystal display, and / or for optical or optoelectronic components, such as, for example, the main light source or any other light source.In this way, by moving the additional light source further away, existing supports or supports made common with other components can be used for its mounting, and the number of parts in the lighting and signaling system is limited.

[0044] According to an optional feature of the invention, the controllable liquid crystal display is attached to the optical element by gluing.

[0045] According to an optional feature of the invention, the controllable liquid crystal display is attached to the optical element by means of an optical adhesive. "Optical adhesive" means a transparent adhesive having a refractive index close to that of at least one of the bonded elements, i.e., in this case, the controllable liquid crystal display and / or the optical element.

[0046] According to an optional feature of the invention, the controllable liquid crystal display is attached to the optical element by overmolding.

[0047] According to an optional feature of the invention, the controllable liquid crystal display comprises two transparent walls, a polymer matrix extending between the two transparent walls in which liquid crystals are dispersed and two electrodes associated respectively with one of the transparent walls so as to pass an electric current through the polymer matrix and its liquid crystals.

[0048] According to an optional feature of the invention, at least one wall comprises a current-conducting layer in direct contact with the polymer matrix and an electrically insulating layer arranged over the conductive layer on the opposite side of the polymer matrix. The conductive layer may be made of indium tin oxide (ITO) and the insulating layer may be made of polycarbonate (PC) or polyethylene terephthalate (PET).

[0049] According to an optional feature of the invention, the controllable liquid crystal display comprises an internal transparent wall facing the light module and an external transparent wall facing the external environment of the lighting and signaling device, the optical element being part of the external transparent wall.

[0050] According to an optional feature of the invention, the controllable liquid crystal display comprises a first part and a second part extending around the periphery of the first part, the diffusion state of one of the parts of the controllable liquid crystal display being independent of the diffusion state of the other of said parts.

[0051] According to an optional feature of the invention, the first part is electrically powered by the control member independently of the second part.

[0052] According to an optional feature of the invention, the lighting and signaling device includes a light ray diffusion element arranged opposite the second part of the controllable liquid crystal display.

[0053] According to an optional feature of the invention, the diffusion element comprises a film installed between the controllable liquid crystal display and the optical element.

[0054] According to an optional feature of the invention, the optical element comprises a main area opposite the first part of the controllable liquid crystal display and a peripheral area to the main area opposite the second part of the controllable liquid crystal display, the diffusion element being constitutive of the peripheral area of ​​the optical element.

[0055] According to an optional feature of the invention, the lighting and signaling device includes a masking element arranged to cover the periphery of the external face of the first portion of the optical element.

[0056] The invention also relates to a motor vehicle equipped with at least one lighting and signaling device in accordance with what has just been mentioned previously.

[0057] Other features, details and advantages of the invention will become clearer upon reading the following description on the one hand, and several examples on the other. of implementation given for guidance purposes only and not as a limitation, with reference to the attached schematic drawings, on which:

[0058] [Fig-1] is a schematic representation of a first embodiment of a lighting and signaling device according to the invention, with an optical block formed of an optical element and a controllable liquid crystal screen, in a first configuration in which at least a portion of the controllable liquid crystal screen is in a projection state, i.e. a so-called transparent state;

[0059] [Fig.2] is a schematic representation of the first embodiment of the lighting and signaling device shown in [Fig.1], in a second configuration in which the controllable liquid crystal display is in a signaling beam emission state, i.e. a so-called diffusing state;

[0060] [Fig.3] is a schematic representation of the first embodiment of the lighting and signaling device shown in [Fig.1], in a third configuration in which the controllable liquid crystal display is in a signaling beam emission state, i.e. a so-called diffusing state;

[0061] [Fig.4] is a schematic representation of a second embodiment of a lighting and signaling device according to the invention;

[0062] [Fig.5] is a schematic representation of a third embodiment of a lighting and signaling device according to the invention.

[0063] The features, variants, and different embodiments of the invention can be combined in various ways, provided they are not incompatible or mutually exclusive. In particular, variants of the invention may be conceived comprising only a selection of features, described hereafter in isolation from the other described features, if this selection of features is sufficient to confer a technical advantage and / or to differentiate the invention from the prior art.

[0064] In the figures, the elements common to several figures retain the same reference.

[0065] Figure 1 illustrates a lighting and signaling device 1 according to the invention, configured to generate a light beam A, namely a lighting beam or a signaling beam, primarily along a longitudinal optical axis L. The lighting and signaling device comprises at least one optical element 2 through which a light beam A is projected to form the lighting beam suitable for illuminating the road scene. The optical element 2 thus forms a luminous surface of the lighting and signaling device, the shape and dimensions of which impact the visual identity of the function.

[0066] The lighting and signaling device 1 includes a light module 4 which is configured to generate the light beam A and direct it towards the optical element 2 and it is understood that this light module 4 can project a light beam suitable for forming a dipped beam type lighting function and / or a main beam type lighting function.

[0067] As shown in Figures 1 to 5, the lighting and signaling device 1 comprises a controllable liquid crystal display 18 attached to the optical element 2 to form an optical block directed towards which the light beam A is directed when the light module 2 is active. The controllable liquid crystal display 18 is arranged more particularly between a first portion 201 of the optical element 2 and the light module 4, such that it is the first portion of the optical element that faces outwards from the lighting and signaling device and forms the luminous surface of this device.

[0068] As will be described in more detail below, the control of the controllable liquid crystal display 18 allows its diffusion state and the overall diffusion state of the optical block to be modified, thus altering the impact that the optical block can have on the projection of the light beam towards the road scene. In other words, the light module is designed to project a light beam that passes through the optical block with little or no deflection if the controllable liquid crystal display 18 is transparent, or with deflection and therefore diffusion if the controllable liquid crystal display 18 is diffusing.

[0069] As illustrated in [Fig. 1], the lighting and signaling device 1 comprises a housing 6 to which the optical element 2 is attached, and more particularly the optical block formed by the optical element and the controllable liquid crystal display 18, and in which the light module 4 is housed. The housing 6 has an opening 5, opposite which extends the optical element 2, and more particularly a first portion 201 which will be detailed below. Where applicable, the optical element 2 can close the opening 5 and form at least part of one of the walls of the housing 6, and more particularly a front wall 62.

[0070] The optical element 2 is, for example, a transparent screen through which the light beam A is able to be projected. The material chosen may, in particular, be polymethyl methacrylate (PMMA) or polycarbonate (PC). The first portion of the optical element 2 is optically neutral, that is to say, it does not deviate the light rays, without this being a limitation of the invention.

[0071] The first portion 201 of the optical element 2 has an external face 8 oriented outwards from the lighting and signaling device 1, this external face being the face visible to external observers when they look at the lighting and signaling device 1. The first portion 201 of the optical element 2 has by Elsewhere, there is an internal face 10, opposite the external face 8, which helps to define, at least partially, a housing for the light module 4 within the casing 6. The internal face 10 is the entry face into the optical element for the lighting beam A, and the opposing external face 8 is the exit face, both for this lighting beam A and for a signaling beam, which will be discussed later. The first portion 201 is substantially centered on the longitudinal optical axis L.

[0072] The first portion 201 of the optical element 2 also includes peripheral edges, here a peripheral edge 9 in the plane of [Fig.1], which connect the outer face 8 to the inner face 10 by forming a straight edge of the first portion 201. Each peripheral edge is arranged substantially in the longitudinal extension of an edge of the aperture 5 of the housing.

[0073] The optical element also includes, in addition to this first portion 201, a second portion 202 which extends the first portion 201, opposite one of the peripheral edges, here the upper peripheral edge 9, to move an entry face of light rays emitted by an additional light source 12 and intended to propagate in the thickness of the optical element 2 to form the signaling beam.

[0074] The second portion 202 extends primarily in a different direction from that of the first portion, and here in a direction substantially perpendicular to that of the first portion 201. To this end, the optical element 2 comprises a bent portion 204 which connects the first portion 201 and the second portion 202. As illustrated, the bent portion 204 allows passage from the second portion to the first portion 201 without hindering the propagation of light rays within the optical element, even though the two portions 201 and 202 are substantially perpendicular. To this end, the bent portion has a minimum radius of curvature of approximately four times the local thickness of the optical element.The thickness is measured for a zone of the curved portion by considering the corresponding osculating circle, in the direction connecting the center of the circle to its point of contact with the curved zone, and the radius of curvature is measured in this same direction at mid-thickness of the curved portion. It should be noted that in the figures the faces of the optical element 2 in the curved portion 204 are represented as segmented, but that these are advantageously curved, and in particular differentiable at every point.

[0075] The first portion 201 forms a principal portion of the optical element insofar as, as mentioned above, it is the portion visible to observers from outside the vehicle, and the portion through which the lighting beam A is likely to pass. This first portion 201 is also the portion through which the rays emitted by the additional light source and propagating within material is intended to exit the device to form a signaling beam.

[0076] The second portion 202 forms a referral portion insofar as light rays emitted in the second portion by the activation of the additional light source are guided by successive total internal reflections from the second portion to the first portion.

[0077] As can be seen in Figures 1 to 5, the lighting and signaling device 1 comprises a main light source 3 forming part of the light module 4 and an additional light source 12 installed opposite the second portion 202 of the optical element 2, and more particularly here, without limiting the invention, opposite an end edge of the second portion 202. The main light source 3 is configured here to participate in the formation of the lighting beam A, after passing through the controllable liquid crystal screen and through the first portion 201 of the optical element, while the additional light source 12 is configured to participate in the formation of a signaling beam after propagation of the rays within the second portion 202 and then the first portion 201 and diffusion at the level of this first portion 201.

[0078] The main light source 3 comprises one or more light-emitting diodes, commonly known as LEDs, configured to generate light beams. The light module 4 in which the main light source is installed further comprises one or more optical devices, such as, for example, a reflector, mirrors, and / or, as illustrated in [Fig. 1], a primary lens 13, and also a projection lens 14. The optical device(s) have the function of directing the light beams emitted by the main source towards the projection lens 14, the latter generating the illumination beam A in the direction of at least the optical element 2. It should be noted that these arrangements mentioned are only non-limiting examples, and that other configurations of light modules are possible for generating the illumination beam.

[0079] The additional light source 12 may also consist of a light-emitting diode but is arranged so as to emit its rays directly into the optical element 2. For this purpose, the additional light source 12 is positioned opposite the second portion 202 of the optical element. In the illustrated example, the additional light source 12 is positioned opposite one end, or transverse edge, 16 of the second portion 202 of the optical element 2, but the shape given to the optical element, with the second portion 202 of the optical element 2 extending from the first portion, outside the path of the rays emitted by the light module and at a distance from the controllable liquid crystal display 18, allows movement the additional light source at a distance from this congested area and thus allows several light coupling configurations.

[0080] The additional light source 12 thus projects light rays into the second portion 202 of the optical element 2, the light rays propagating as previously mentioned by successive total internal reflections within the light guide formed by the second portion 202 of the optical element until they encounter a diffusing element which deflects the path of this ray towards the external face 8 at an angle suitable for refracting towards the road scene and contributing to generating a signal beam for other road users.

[0081] The main light source and the additional light source 12 can be powered simultaneously or separately and the power supply to each of the sources is a function of the diffusion state of the controllable liquid crystal display 18.

[0082] The controllable liquid crystal display 18 can be attached to the optical element 2 by bonding, with adhesive that can be applied between the controllable liquid crystal display 18 and the optical element 2, for example on the periphery of the contact face between the controllable liquid crystal display 18 and the optical element 2, or alternatively, it can be attached to the optical element 2 by an overmolding operation. This alternative allows the controllable liquid crystal display 18 to be bonded to the optical element 2 without inserting adhesive between the controllable liquid crystal display 18 and the optical element 2, which could have a minimal effect on the propagation of light rays emitted by the light module through the optical block formed by the controllable liquid crystal display 18 and the optical element 2.

[0083] The controllable liquid crystal screen 18 allows the level of diffusion of the optical block that it helps to form with the optical element 2 to make the light beam A diffuse or not when it passes through this optical block, or to form a diffusing screen opposite an internal face of the optical element 2 and promote the output towards the road scene in a signaling beam of light rays emitted from the second portion and brought back into the first portion due to the light guide function provided by this second portion of the optical element.

[0084] To this end, the controllable liquid crystal display 18 is arranged between the light module 4 and the optical element 2 so that it contributes to forming a diffusing face of the optical element opposite the road scene when the controllable liquid crystal display 18 is configured accordingly. It is understood here that in this arrangement, the light beam A is made to pass through the controllable liquid crystal display 18 before passing through the optical element 2 when the controllable liquid crystal display is configured to be transparent to the passage of light rays.

[0085] According to the invention, the controllable liquid crystal display 18 is capable of assuming different diffusion states, including at least one projection state allowing the projection of the light beam A through the optical block to form a lighting beam at the output of the optical block and in which the controllable liquid crystal display 18 is transparent and an emission state of a signaling beam in which the controllable liquid crystal display 18 is not transparent.

[0086] The projection state of the controllable liquid crystal display 18 is associated with the emission of the light beam A by the light module and the use of this light beam A to generate a low beam or high beam type lighting function, while the emission state of the controllable liquid crystal display 18 is either associated with the emission of the light beam A and its transformation by diffusion or associated with the emission of light rays directly into the light guide formed by the optical element via the implementation of the additional light source.

[0087] These different states of the controllable liquid crystal display 18 are defined according to the diffusion veil, or Haze index, which the said controllable liquid crystal display 18 presents in each of these states, the diffusion veil corresponding to the percentage of light rays succeeding in passing through an object they encounter.

[0088] For example, in the projection state of a lighting beam, the controllable liquid crystal display 18 exhibits a low diffusion haze, i.e., for example, less than 6%. Advantageously, the diffusion haze of the controllable liquid crystal display 18 is approximately 3% when said display 18 is in the projection state.

[0089] Conversely, in the emission state of a signaling beam, the controllable liquid crystal display exhibits a non-diffusion state, i.e., a high diffusion haze, for example, greater than 90%. Advantageously, the diffusion haze of the controllable liquid crystal display 18 is approximately 98% when said display is in the emission state.

[0090] The modification of the diffusion veil of the controllable liquid crystal screen 18 is achieved by a modification of the power supply of this screen, which has the effect of modifying the orientation of the liquid crystals within the screen and allowing to generate more or less deviation of the light rays passing through the screen by these liquid crystals.

[0091] More specifically, the controllable liquid crystal display 18 comprises two transparent walls 20, 22 and a polymer matrix 24 in which liquid crystals are randomly dispersed and which extends between the two transparent walls 20, 22. The controllable liquid crystal display also includes electrodes connected respectively to each of the transparent walls 20, 22 to allow the passage of electric current within the controllable liquid crystal display, and more specifically to allow the passage of current from one transparent wall to the other through the polymer matrix. Each of the walls may in particular comprise two layers stacked one on top of the other, with a current-conducting layer, for example made of indium tin oxide (ITO), directly in contact with the polymer matrix, and an electrically insulating layer, for example made of polycarbonate (PC), placed over the conductive layer opposite the polymer matrix.

[0092] The controllable liquid crystal display 18 more particularly comprises, an internal transparent wall 20 facing the light module 4 and an external transparent wall 22 facing the external environment of the lighting and signaling device 1, the first portion 201 of the optical element 2 being against the external transparent wall 22. Where appropriate, if the manufacturing means permit, the first portion 201 of the optical element 2 may form the external transparent wall 22 and more particularly the electrically insulating layer of this external transparent wall.

[0093] The lighting and signaling device 1 comprises a control element 28 for the controllable liquid crystal display 18, designed to control the power supply to the controllable liquid crystal display 18 via electrodes and a power cable 26 shown schematically in the figures. The control element 28 is configured to power the controllable liquid crystal display 18, and more particularly the polymer matrix 24 and the liquid crystals embedded and randomly dispersed within it, so as to orient the liquid crystals in a direction parallel to the main direction of the current within the polymer matrix when the display is powered, thus limiting the impact of the liquid crystals on the path of the light rays.It is understood that the resulting electrical supply to the controllable liquid crystal display 18 causes an arrangement of the liquid crystals which makes the display change from a diffusing state to a transparent state, that is to say here from a state of emitting a signaling beam to a state of projecting a lighting beam.

[0094] If necessary, intermediate states can be given to the controllable liquid crystal display 18 by playing on the intensity of the electric current brought through the polymer matrix.

[0095] More particularly, the initial state of the controllable liquid crystal display 18 is the diffusing state, which corresponds to the state of the controllable liquid crystal display 18 when the polymer matrix 24 and the liquid crystals embedded in it are not electrically powered and the arrangement of the liquid crystals remains random, so that the light rays that happen to meet and / or pass through the screen and the optical block that it helps to form are reflected and refracted and emerge in the diffuse state.

[0096] As soon as the control element 28 transmits an electrical power supply to the polymer matrix 24, in particular via the electrodes and the cable 26, the liquid crystals organize themselves among themselves, notably by aligning themselves perpendicularly with respect to the transparent walls carrying the electrodes, so that the controllable liquid crystal screen goes into a projection state, the light beam A can then pass through the controllable liquid crystal screen 18 towards the optical element 2 in order to form a regulatory lighting beam on the road scene.

[0097] These two different diffusion states are particularly visible in Figures 1 to 3, in which a controllable liquid crystal display 18 is shown partly transparent and partly non-transparent in [Fig. 1], and entirely in a non-transparent state in Figures 2 and 3.

[0098] The figures make particularly visible the interest of the invention of having an optical element 2 conforming to what has just been described, that is to say with two portions 201, 202, in the context of a lighting and signaling device equipped with a controllable liquid crystal screen 18 interposed between the light module 4 and the optical element 2 on the path of the lighting beam A.

[0099] The presence of the second portion 202, which extends the first portion 201 of the optical element 2 and allows the position of the entry face of the rays intended to form the signaling beam to be moved, and thus the position of the additional light source 12 to be moved, makes it possible to position the additional light source 12 in the most advantageous area of ​​the housing. In the example illustrated in Figures 1 and 2, the additional light source 12 is thus positioned approximately directly above the main light source 3, which allows them to be mounted on a common support 11, fixed to a wall of the housing.

[0100] Furthermore, it is noteworthy that the light guide formed by the second portion 202 of the optical element 2 extends in this example along a side wall 60 of the housing 6, substantially perpendicular to a front wall 62 of the housing in which the opening 5 is formed. This can facilitate holding the optical element in position on the housing by means of fastening, for example staples or clips made integral with said wall of the housing and which are engaged with the second portion 202.

[0101] We will now describe several embodiments of the invention, including a first embodiment illustrated in Figures 1 to 3, a second embodiment illustrated in [Fig. 4], and a third embodiment illustrated in [Fig. 5]. Each of the embodiments described hereafter can be implemented alternatively or in addition to one or more other embodiments, unless otherwise stated. Furthermore, the common features of the different embodiments and of what has been described previously will have the same reference numerals in each of the subsequent descriptions of the embodiments.

[0102] In a first embodiment of the invention, and as particularly visible in Figures 1 to 3, the controllable liquid crystal display 18 comprises a first part 30 and a second part 32 extending around the periphery of the first part 30, the diffusion state of one of the parts being independent of the diffusion state of the other part. In other words, the first part 30 is electrically powered by the control element 28 independently of the second part 32, so that, depending on the application, an electrical supply of the same intensity can be sent to both parts simultaneously, or one of the two parts, in particular the second part 32, may not be powered while the first part is.

[0103] The second part 32 can in particular be made electrically independent from the first part 30 by a laser cutting of the surface of the transparent walls, which allows a separate power supply to each of the two parts.

[0104] The second part 32 is formed at the periphery of the screen over a dimension such that the light beam A emitted by the light module 4 is projected onto the controllable liquid crystal screen 18 essentially or entirely onto the first part 30.

[0105] For example, in a first configuration illustrated in [Fig. 1], the first part 30 of the controllable liquid crystal display 18 is electrically powered to orient the liquid crystals in the direction of the current flowing within the polymer matrix, so that this first part 30 is in a state of projecting a beam of light, i.e., in a state of high transparency. And in this first configuration, the second part 32 of the controllable liquid crystal display is not electrically powered, so that the liquid crystals remain randomly dispersed within the polymer matrix of this second part 32, and this second part is in a state of emitting a beam of light, i.e., a diffusing state, in a state of low transparency.

[0106] In this first configuration, the light beam A emitted by the light module is projected through the first part 30 of the controllable liquid crystal display 18, and it is understood that the first part 30 of the controllable liquid crystal display 18 and the first portion 201 of the optical element 2 form an assembly which does not deflect the light beam A, so that the lighting function of the light module, whether it be a low beam or high beam function, is not impacted by the presence of the controllable liquid crystal display 18 and can comply with regulatory standards.

[0107] The emission of light rays by the additional light source can also be provided in order to improve the homogeneity of appearance of the lighting and signaling device.

[0108] According to a second configuration illustrated in [Fig. 2], the first and second parts of the controllable liquid crystal display 18 are each in a diffusing state, i.e., a signaling beam emission state. Neither the first part 30 nor the second part 32 of the controllable liquid crystal display 18 are electrically powered by the control element 28, so that the liquid crystals in each of these parts remain in their original position, i.e., randomly dispersed in the polymer matrix, in orientations different from each other. In this second configuration, the light module 4 is inactive, so that no light beam attempts to pass through the optical block formed by the controllable liquid crystal display 18 and the optical element 2. No lighting function is provided by the lighting and signaling device 1 of the invention.

[0109] Conversely, the additional light source 12 arranged opposite the second of the optical element 2 is activated so as to emit light rays into the thickness of the optical element. As mentioned previously and visible in [Fig. 2], the light rays are made to encounter a diffusing element, formed by the diffusing state of the controllable liquid crystal screen 18 pressed against the inner face 10 of the optical element 2, and they are then deflected to be directed opposite the outer face 8 at an angle allowing their refraction out of the optical element, to form a signaling beam.

[0110] The diffusing state of the controllable liquid crystal display 18 contributes to generating a signaling beam, via the activation of the additional light source, so that this diffusing state corresponds, as mentioned, to an emission state of a signaling beam.

[0111] It can also be provided that the light module projects a beam of light in order to make the diffusion of light rays even more homogeneous.

[0112] According to a third configuration illustrated in [Fig. 3], the first part 30 and the second part 32 of the controllable liquid crystal display 18 are also in a diffusing state. This third configuration differs in particular from the second configuration in that the light module is active, so that a light beam A is made to pass through the first part 30, now diffusing unlike the first configuration of [Fig. 1], of the controllable liquid crystal display 18. The light beam A is thus deflected and made diffuse by the random arrangement of the liquid crystals to form a signaling beam at the output of the lighting and signaling device of the invention. It should be noted that in the illustration of [Fig.3], the single light ray shown is reflected between the inner and outer faces of the optical element up to the peripheral edge 9 before being diffused at the level of the inner face, but that this configuration, if it . is possible, but not the most probable. Most of the rays that entered the first portion through the bent portion forming the junction between the second portion and the first portion are scattered before reaching the opposite peripheral edge.

[0113] According to an alternative configuration and not shown here, the diffusion of a light beam A emitted by the light module and the diffusion of light rays emitted by the additional light source can be combined to increase the intensity of a signaling beam generated by the lighting and signaling device.

[0114] Furthermore, in either configuration, the diffusion haze of the controllable liquid crystal display 18 can take intermediate values, notably by varying the power supply intensity from one configuration to another. The power supply intensity can also vary depending on the concentration of liquid crystals dispersed in the polymer matrix.

[0115] Alternatively, it could also be envisaged that only the second part 32 is energized, while the first part 30 is not. It is therefore understood that the first part 30 is in an emitting state while the second part 32 is in a projecting state.

[0116] It can also be foreseen that the first part 30 and the second part 32 are each electrically powered, each of the parts therefore being in a projection state.

[0117] According to a second embodiment of the invention, and as seen in [Fig.4], the lighting and signaling device 1 comprises a light beam diffusion element 34 arranged opposite the second portion 32 of the controllable liquid crystal display 18.For example, the diffusion element 34 is a film installed between the controllable liquid crystal display 18 and the optical element 2, the film of the diffusion element 34 of light rays extending around the periphery of the optical element so that the light rays propagating by successive reflections within the different portions 201, 202 of the optical element 2 and meeting this diffusing film are caused to be deflected and subsequently meet the external face 8, or exit face, of the first portion 201 of the optical element at an angle such that they can be refracted to exit the optical element and form a signaling beam, in the direction of the external environment of the lighting and signaling device 1.

[0118] It can thus be defined that the first portion 201 of the optical element 2 comprises a main zone opposite the first part 30 of the controllable liquid crystal display 18 and a peripheral zone adjacent to the main zone opposite the second part 32, the diffusion element 34 being constitutive of the peripheral zone of the optical element 2. It is understood that the diffusion element 34 is an integral part of the optical element 2 and can, for example, form a graining pattern at the periphery of optical element 2 in order to diffuse the light rays passing through optical element 2 at its periphery.

[0119] It should be noted that the presence of a diffusion element 34 on the periphery of the optical element 2 is not incompatible with the different configurations mentioned previously with reference to the first embodiment.

[0120] In this second embodiment, the propagation of the light rays emitted by the additional light source 12 within the optical element 2 for the realization of the signaling function is equivalent to what has been mentioned previously, with light rays which enter directly into the second portion 202 of the optical element 2 by the transverse edge forming an end 16 of this second portion 202, these rays being made to propagate in the direction of the first portion 201 in particular by following the angled portion 204.At the junction between the second portion 202 and the first portion 201 of the optical element 2, and more particularly at the junction between the bent portion 204 and the first portion 201, the rays are made to cross the peripheral zone of the first portion 201 before entering the main zone in which they are made to encounter patterns which favor their exit by refraction by the exit face formed by the external face 8 of the first portion 201 of the optical element 2. .

[0121] Furthermore, the second embodiment also differs in its representation from the first embodiment in that the second portion 202 of the optical element 2 is less extended so that its transverse edge 16 and the corresponding position of the additional light source 12 are no longer aligned with the main light source of the light module 4. In this configuration, where the additional light source 12 is here close to the control member 28 of the controllable liquid crystal display 18, the support 11 on which the additional light source 12 is fixed is this time a common support with the control member 28.

[0122] Of course, it is understood that this arrangement of a second portion 202 of the optical element 2 which is shortened and of a support 11 which is shared with the control member 28 could be implemented in the first embodiment and that the corresponding arrangement of the first embodiment could be implemented in the second embodiment.

[0123] According to a third embodiment, and as shown in [Fig. 5], the lighting and signaling device 1 comprises a masking element 36 arranged to cover the periphery of the outer face 8 of the optical element 2. For example, the masking element 36 is understood to be a wall extending from the housing 6 opposite the outer face 8 of the optical element 2 and covering at least the periphery of the optical element 2. The wall may thus have a profile in particular, cutting out the contours of the signaling beams emitted by the lighting and signaling device 1 according to the invention, and thus ensuring a recognizable visual identity of the vehicle.

[0124] Here again, it should be noted that the presence of a masking element 36 on the periphery of the optical element 2 is not incompatible with the different configurations mentioned previously with reference to the first embodiment.

[0125] Furthermore, the third embodiment also differs in its representation from the previously described embodiments in that the support 11 for the additional light source is no longer shared with another component of the housing. The advantage of having relocated the additional light source 12 by forming the optical element 2 into two portions with a reflecting portion is that it allows the support 11 to be placed against the side wall of the housing in a clear area, thus associating cooling means 110, here finned, with the support, the positioning of which optimizes thermal performance. By way of non-limiting example, the cooling means associated with the support for the additional light source can extend through said side wall.

[0126] Here again, it is understood that this arrangement specific to the third embodiment of the additional light source 12 and associated cooling means 110 could be implemented with a configuration of the controllable liquid crystal display 18 more specifically described in the first embodiment or in the second embodiment.

[0127] As described above, the invention achieves the goals it set for itself by proposing a lighting and signaling device that enables the performance of a lighting function with the presence of a controllable liquid crystal screen to make the lighting beam more diffuse over an entire output surface of the rays visible to an external observer, while also enabling the performance of a signaling function via the same output surface, with an optical element that is both traversed by the lighting beam and capable of generating a signaling beam, the optical element having a reflection portion allowing the light source at the origin of the rays forming the signaling beam to be moved in order to position this light source in an optimal area.

[0128] The present invention is not limited to the means and configurations described and illustrated herein and also extends to any equivalent means and configuration as well as to any technically operative combination of such means.

Claims

Demands

1. Lighting and signaling device (1) comprising at least one light module (4) and an optical element (2), the light module (4) comprising a main light source (3) capable of being driven to participate in generating a lighting beam (A) along a longitudinal optical axis (L), said light beam being capable of being projected through the optical element (2), characterized in that the optical element (2) comprises a first portion (201) intended to be across the light beam (A) and a second portion (202) arranged in the extension of the first portion so as to be outside the path of the lighting beam (A), the lighting and signaling device further comprising an additional light source (12) arranged opposite the second portion (202),said second portion (202) being configured to guide the light emitted by said additional light source (12) towards the first portion (201), said lighting and signaling device also being characterized in that the lighting and signaling device (1) comprises a controllable liquid crystal display (18) affixed to the first portion of the optical element (2), the controllable liquid crystal display (18) being capable of assuming different diffusion states, including at least one projection state of the light beam (A) in which the controllable liquid crystal display (18) is transparent and a signaling beam emission state in which the controllable liquid crystal display (18) is at least partially diffusing.

2. Lighting and signaling device (1) according to claim 1, wherein the first portion (201) of the optical element (2) has an inner face (10) facing inwards towards the interior of the lighting and signaling device and an outer face (8) opposite said inner face (10) and facing outwards from the device, the optical element (2) being characterized in that the first portion (201) has, opposite its junction with the second portion (202), a peripheral edge connecting the inner face (10) to the outer face (9).

3. A lighting and signaling device (1) according to claim 1 or 2 and comprising a housing (6) configured to house the components of said device, the housing (6) having an opening (5) opposite which is positioned the first portion (201) of the optical element (2), in which the second portion (202) of the optical element (2) is arranged along a side wall (60) of the housing (6).

4. Lighting and signaling device (1) according to any one of claims 1 to 3, wherein the first portion (201) and the second portion (202) form a single optical element.

5. Lighting and signaling device (1) according to claim 4, wherein the portions (201, 202, 204) of the optical element (2) are made in one piece and out of the same material.

6. Lighting and signaling device (1) according to any one of claims 1 to 5, wherein the optical element (2) comprises an angled portion (204) linking the first portion (201) to the second portion (202).

7. Lighting and signaling device (1) according to any one of claims 1 to 6, wherein a control element (28) of the controllable liquid crystal display (18) is configured to electrically supply the controllable liquid crystal display (18) so that the controllable liquid crystal display (18) changes from the defined projection state to the defined emission state and vice versa as a function of a change in electrical supply.

8. Lighting and signaling device (1) according to claim 7, wherein the control member (28) is configured to activate and / or control the additional light source (12).

9. Lighting and signaling device (1) according to any one of claims 1 to 8, wherein the additional light source (12) is disposed on a support element (11) which is common to said additional light source (12) and to at least one other electronic or optical component of the lighting and signaling device.

10. Motor vehicle equipped with at least one lighting and signaling device (1) characterized according to any one of claims 1 to 9.

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