Optical element for an illuminating device of a motor vehicle

Abstract

The present invention relates to an optical element (20) of a lighting module (2) intended for use in a motor vehicle, the optical element (20) comprising a light guide (22) that comprises at least a first guide portion (24) that contributes to the formation of at least one first lighting function and a second guide portion (26) that contributes to the formation of a second lighting function, the first lighting function being distinct from the second lighting function, wherein the first guide portion (24) and the second guide portion (26) lead into an end portion of the light guide, and the junction between the first guide portion (24) and the second guide portion (26) forms a cut-off edge (36), which creates an upper limit for the first lighting function.

Description

DESCRIPTION OPTICAL ELEMENT FOR AN ILLUMINATING DEVICE OF A MOTOR VEHICLE

[0001] The present invention relates to the field of lighting devices installed in a motor vehicle. The present invention relates more particularly to an optical element of a lighting module participating in the realization of two distinct lighting functions. The invention also relates to a lighting module comprising the optical element.

[0002] Motor vehicles are commonly equipped with headlights located at the front of the motor vehicle. These headlights are usually composed of a housing which is closed by a transparent wall through which one or more light beams pass. This housing houses at least one light module, comprising a light source and an optical system configured to conform the light generated by the light source in order to provide specific lighting and / or signaling services for the vehicle.

[0003] In order to increase the compactness of the equipment installed in a vehicle, the light modules are increasingly capable of generating several light functions such as two separate lighting functions, for example a dipped beam type lighting function and another main beam type lighting function.

[0004] Such light modules need to be improved. The size of the various elements used to process the light and achieve the desired lighting characteristics within these modules is still too large.

[0005] In particular, the arrangement of the different elements within these light modules requires a projection lens with large dimensions, which limits the possible compactness of the light module.

[0006] The present invention falls within this context and aims to overcome at least some of the drawbacks of the prior art and in particular to propose a light module whose size is reduced, partly by means of an element optics involved in the realization of two distinct lighting functions. This optical element has a configuration allowing the size of the projection lens to be reduced.

[0007] Thus, the main subject of the present invention is an optical element of a light module intended to equip a motor vehicle, the optical element comprising a light guide comprising at least a first guide portion participating in the formation of a first light beam capable of performing at least a first light function and a second guide portion participating in the formation of a second light beam capable of performing at least a second light function, the first light function being distinct from the second light function, the first guide portion and the second guide portion opening into an end portion of the light guide, the junction between the first guide portion and the second guide portion forming a cut-off edge, the first light beam comprising an upper cut-off formed by the cut-off edge.

[0008] The light module is intended to be housed in a headlight of a motor vehicle. In particular, it allows the implementation of two distinct lighting functions, including a cut-off lighting function, i.e. a lighting function such that the generated beam must be cut off so as not to dazzle road users located in front of the vehicle. The light guide of the optical element makes it possible to guide the light through the optical element while conforming the light rays passing through it to form a lighting function with the desired characteristics.

[0009] The first guide portion and the second guide portion open into the terminal portion. It is understood that the terminal portion is common to the first guide portion and the second guide portion. The light rays passing through the first guide portion or the second guide portion exit said guide portion to reach the terminal portion.

[0010] The optical element is configured to participate in the formation of a first light beam and a second light beam, each of these first and second light beams participating in the formation of at least one of said light functions distinct from one another. It is understood that each of the first and second guide portions is configured to participate in the formation of at least one light beam when it is crossed by light rays. More specifically, the first guide portion participates alone, that is to say without the second guide portion, in the formation of the first light beam, itself participating alone in the realization of the first light function. This first light function is thus ensured by activating the light source associated with the first guide portion, so that rays propagate only in the first guide portion then in the terminal portion. This first light function may be a regulatory lighting function, that is to say which complies with a photometric grid imposed by regulations, and it may in particular be a dipped beam type lighting function, with a cut-off beam.For this purpose, the first light beam comprises an upper cut-off formed by blocking the rays within the optical element via the cut-off edge. This thus makes it possible to limit the height of the first light function formed by the first light beam. This upper cut-off makes it possible not to dazzle other road users, and in particular those traveling in the opposite direction to the direction of travel of the vehicle.

[0011] According to a characteristic of the invention, this first guide portion can participate, in combination with the second guide portion, in the formation of a light function, and in particular a regulatory light function, such as for example a main beam type lighting function. This main beam type lighting function is thus ensured by activating the light source associated with the first guide portion and by activating the light source associated with the second guide portion, so that rays propagate both in the first guide portion and in the second guide portion to meet in the terminal portion.This high beam type lighting function is formed by an overall beam formed from the first light beam comprising the upper cut-off obtained via the light rays propagating in the first guide portion and from the second light beam obtained via the light rays propagating in the second guide portion. Alternatively, the first light beam and the second light beam may form in combination, for example, a dipped beam type lighting function. For this purpose, the first light beam. forms, by means of the upper cut-off, the upper part of the dipped beam type lighting function, and in particular a narrow light beam with an upper cut-off provided with a projection and the second light beam forms the lower part of the dipped beam type lighting function, and in particular a wide light beam with a horizontal upper cut-off.

[0012] The cutting edge is at the junction between the first guide portion and the second guide portion. It is understood that the first guide portion is provided directly on a first side of the cutting edge and the second guide portion is provided directly on a second side of the cutting edge, the first side being opposite the second side.

[0013] According to a feature of the invention, the first guide portion and the second guide portion each comprise at least two reflective surfaces configured to totally reflect light rays reaching said reflective surfaces. In particular, the first guide portion and the second guide portion each comprise a first reflective surface and a second reflective surface.

[0014] These reflective surfaces are configured such that light rays reaching said reflective surfaces are reflected via total internal reflection. More specifically, the light rays emitted in each guide portion reach one reflective surface, corresponding to the first reflective surface, and are reflected towards the other reflective surface, corresponding to the second reflective surface, from which the light rays are once again reflected towards the terminal portion and the exit of the optical element. The reflective surfaces thus form surfaces for returning the light rays.

[0015] According to a characteristic of the invention, the optical element comprises a clearance of material which separates the first guide portion from the second guide portion, opposite the terminal portion.

[0016] According to a characteristic of the invention, the material clearance has an asymmetrical shape relative to a cutting plane extending between the two guide portions.

[0017] According to a characteristic of the invention, the first guide portion is delimited by two successive intersecting walls of the material clearance among which a cut-off wall, said cut-off wall being distinct from the two reflective surfaces of this first guide portion.

[0018] According to a characteristic of the invention, the cutting wall is inscribed in the cutting plane.

[0019] According to a characteristic of the invention, the cut-off wall extends the second reflective surface of the first guide portion, so that the cut-off wall is bordered longitudinally by the second reflective surface and by the cut-off edge.

[0020] According to a characteristic of the invention, the cut-off edge is formed by one of the two reflective surfaces of the second guide portion and by the cut-off wall of the first guide portion.

[0021] According to a characteristic of the invention, the cutting wall comprises a reflective surface.

[0022] According to a characteristic of the invention, the optical element comprises an exit face through which light rays are able to exit the optical element, the cut-off wall being perpendicular, or substantially perpendicular, to the exit face. The exit face of the optical element may, where appropriate, have a curvature and in particular a convex shape in which case it should be understood that the cut-off wall lies mainly in a plane perpendicular to a main elongation plane of the exit face. It should be noted that by substantially perpendicular, the aim is to protect a possible slight inclination of the plane in which the cut-off wall lies relative to this plane perpendicular to the exit face.

[0023] According to a characteristic of the invention, the first guide portion and the second guide portion each have an input end and an output end, the junction of the output ends of said guide portions forming the cut-off edge, at least one collimator being arranged at the input end of the first guide portion and at least one other collimator being arranged at the input end of the second guide portion.

[0024] According to a characteristic of the invention, the input end of the first guide portion and the input end of the second guide portion are in the same plane. The arrangement of the input ends of the first guide portion and of the second guide portion in the same plane makes it possible to contain the size of the light module by preventing the light sources from being arranged on either side of the optical element.

[0025] According to a characteristic of the invention, the plane in which the inlet end of the first guide portion and the inlet end of the second guide portion are located is parallel to the plane in which the outlet face mainly extends.

[0026] According to a characteristic of the invention, the first guide portion and the second guide portion are each inclined towards each other such that the distance separating the outlet end of each of said guide portions is less than the distance separating the inlet end of each of said guide portions.

[0027] According to a characteristic of the invention, the cutting edge has a radius of curvature of less than 0.3 mm.

[0028] According to a characteristic of the invention, the cutting edge has a radius of curvature less than or equal to 0.1 mm.

[0029] According to a feature of the invention, the optical element is formed from polymethyl methacrylate acrylic. Alternatively, and without this being exhaustive, the optical element may be formed from polycarbonate. Alternatively, the optical element may be formed from polymethyl methacrylimide.

[0030] The invention also relates to a light module comprising an optical element conforming to any one of the aforementioned characteristics, the light module comprising at least two light sources and a projection lens, at least one light source being arranged opposite the first guide portion and at least one light source being arranged opposite the second guide portion, each light source being configured to emit light rays in the associated guide portion of the optical element, the optical element being configured to direct the light rays towards the projection lens.

[0031] According to a feature of the invention, the projection lens has an object focus arranged at the cut-off edge of the optical element. The expression at the cut-off edge is intended here to cover the fact that the object focus of the projection lens is on the cut-off edge or close to it, within plus or minus 5 mm of said cut-off edge.

[0032] According to a characteristic of the invention, each light source of the light module is arranged on the same support.

[0033] According to a characteristic of the invention, the projection lens has a height less than or equal to 45 mm, the first guide portion and the second guide portion being arranged one above the other in a vertical direction, said height being measured parallel to this vertical direction. This dimension of the projection lens is notably possible due to the compactness of the optical element. Indeed, on the one hand the arrangement of the light sources on the same side of the optical element and on the other hand the respective inclination of each guide portion makes it possible to limit the size of the optical element and thus to limit the size of the projection lens.

[0034] Other characteristics, details and advantages of the invention will emerge more clearly on reading the description which follows on the one hand, and examples of embodiment given for informational and non-limiting purposes with reference to the attached schematic drawings on the other hand, in which:

[0035] [Fig.l] represents a general view of a light module according to the invention;

[0036] [Fig.2] represents an exploded view of the light module represented by figure 1 on which are visible a printed circuit board, an optical element according to the present invention and a projection lens;

[0037] [Fig.3] represents a sectional view of the optical element visible in Figure 2;

[0038] [Fig.4] represents a sectional view of the light module represented by the figure 1 according to the section plane of figure 3 in which light rays forming a first light function are represented;

[0039] [Fig.5] represents a sectional view of the light module represented by figure 4 on which light rays forming a second light function are represented;

[0040] [Fig.6] represents a perspective view of the optical element represented by figure 3 making visible a clearance of material and collimators of the optical element.

[0041] The features, variants and different embodiments of the invention may be combined with each other in various combinations, provided that they are not incompatible or mutually exclusive. In particular, variants of the invention may be conceived comprising only a selection of features described below in isolation from the other features described, if this selection of features is sufficient to confer a technical advantage or to differentiate the invention from the state of the art.

[0042] In the figures, elements common to several figures retain the same reference.

[0043] In the following description, we will refer to an orientation depending on the Longitudinal, Vertical and Transverse axes as defined by the trihedron L, V, T shown in figures 1 to 6.

[0044] Figure 1 represents a light module 2 according to the present invention. This light module 2 is intended to equip a motor vehicle and to ensure, in the embodiment shown, the lighting of the external environment located in front of the motor vehicle.

[0045] As seen in Figure 1, the light module 2 extends in a longitudinal main elongation direction, i.e. parallel to the axis L. The light module 2 comprises a projection lens 4 arranged at a first longitudinal end 6 of the light module 2 and at least one printed circuit board 8, seen in Figure 2, arranged at a second longitudinal end 10 of the light module 2, opposite the first longitudinal end 6.

[0046] The printed circuit board 8, which will be described in more detail in connection with FIG. 2, is protected by a housing 12 which forms the casing of the light module 2. A longitudinal end, at the level of the second longitudinal end 10, of this housing 12 covers at least in part the face of the printed circuit board 8 opposite the projection lens 4. The opposite end of the housing 12, at the level of the first longitudinal end 6, is integral with the projection lens 4. projection 4. More specifically, the housing 12 makes it possible to maintain the projection lens 4 in a given position.

[0047] As mentioned above, the light module 2 is intended to generate at least two light functions and in this case two regulatory lighting functions, that is to say corresponding to the different standards in force, it being understood that it would also be possible for these two light functions to participate only in the realization of regulatory lighting functions, or in other words that these two light functions are not in themselves regulatory but need to be combined with other light functions to form in combination regulatory lighting functions. For this purpose, the printed circuit board comprises light sources capable of generating light rays in the direction of the projection lens 4, said light rays being capable of exiting the light module 2 through said projection lens 4.

[0048] Figure 2 illustrates an exploded view of the light module 2 visible in Figure 1. It should be noted that the fixing means, the connection means and the housing 12 are not shown in this Figure 2.

[0049] As visible in Figure 2, the printed circuit board 8 comprises a plurality of electronic components participating together or individually in the operation of the light module 2. The printed circuit board comprises in particular a first light source 14 and a second light source 16. Each of these light sources 14, 16 comprises one or more light-emitting diodes 18 connected to one or more tracks of the printed circuit board 8.

[0050] In the embodiment shown, each of these light sources 14, 16 is intended to form a distinct light function. The first light source 14 is intended to form a first light beam participating in the formation of at least one first light function which is a dipped beam type lighting function making it possible to form a low beam on a regulatory photometric grid. The second light source 16 is intended to form a second light beam participating in the formation of at least one second light function which is a complementary main beam type lighting function making it possible to form a high beam on a regulatory photometric grid. The main beam type lighting function complementary form, in combination with the dipped beam type lighting function, a main beam type function. It is understood that the first light function and the second light function are two separate light functions.

[0051] The first light function and / or the second light function may each be a regulatory lighting function. In the example mentioned of a high beam type function obtained by the combination of the two light functions respectively formed by each of the two light beams, the first light function is a regulatory lighting function and the combination of the two light functions is another regulatory lighting function.

[0052] Arranged between the printed circuit board 8 and the projection lens 4, the light module 2 comprises an optical element 20, which will be described in more detail in connection with FIGS. 3 to 6. This optical element 20 is made of polymethyl methacrylate (PMMA). Alternatively, the optical element 20 may be made of polycarbonate (PC). Alternatively, the optical element 20 may be formed of polymethyl methacrylimide (PMMI).

[0053] The light rays emitted by the light sources 14, 16 pass through the optical element 20 before reaching the projection lens 4 and exiting the light module 2.

[0054] The passage of the light rays in the optical element 20 makes it possible, as will be described in more detail in connection with FIGS. 4 and 5, to obtain a light function with the desired characteristics. It is understood that the light rays are deflected within the optical element 20 in an appropriate manner to be directed towards the projection lens and form their respective light function.

[0055] Figure 3 represents a sectional view of the optical element 20 along a sectional plane extending longitudinally and vertically.

[0056] As seen in Figure 3, the optical element 20 comprises a light guide 22 comprising a first guide portion 24 and a second guide portion 26. Each guide portion 24, 26 extends between an input end 28 of the light rays and an output end 30 of the light rays. In the embodiment shown, the light rays emitted by the first source light source 14 enter the optical element 20 through the input end 28 of the first guide portion 24 while the light rays emitted by the second light source 16 enter the optical element 20 through the input end 28 of the second guide portion 26.

[0057] It is understood in view of what has been described previously that the first guide portion 24, associated with the first light source 14, participates in the formation of the first light function and that the second guide portion 26, associated with the second light source 16, participates in the formation of the second light function.

[0058] The first guide portion 24 and the second guide portion 26 open into an end portion 32 of the light guide 22. This end portion 32 is bordered longitudinally on the one hand by the output ends 30 of the first guide portion 24 and of the second guide portion 26 and on the other hand by an output face 34 of the optical element 20.

[0059] More specifically, the first and second guide portions 24, 26 join to form the end portion 32 of the light guide 22. The junction of the first guide portion 24 and the second guide portion 26, at their output end 30, forms a cut-off edge 36. This cut-off edge 36 is useful for forming the first light function with the desired characteristics, in particular by forming a cut-off of the first light beam. This cut-off is observed on a regulatory photometric grid by a clear upper limit of the first light function.

[0060] The exit face 34 of the optical element forms the face through which the light rays, emitted independently through the first guide portion 24 and / or the second guide portion 26, exit the optical element 20 to reach the projection lens 4.

[0061] This exit face 34 extends mainly in a plane, this plane extending vertically and transversely such that the light rays passing through the optical element 20 are caused to pass through the plane of the exit face 34. It should be noted that the exit face 34 of the optical element 20 may have a convex shape.

[0062] Opposite the plane of the exit face 34, the entry ends 28 of the first guide portion 24 and of the second guide portion 26 are inscribed in the same plane which is parallel to the plane of the exit face 34. In this way, the light sources intended to be opposite the entry ends can be arranged on the same side of the optical element, which allows optimization of the space requirement. Alternatively, the entry ends can be inscribed in parallel and distinct planes, each parallel or slightly inclined relative to the plane of the exit face.

[0063] Furthermore, the first guide portion 24 and the second guide portion 26 are inclined towards each other. It is understood that such an inclination allows, in accordance with what has been described previously, the first and second guide portions 24, 26 to meet at their outlet end 30. It results from this inclination of the first and second guide portions 24, 26 that the distance separating the inlet ends 28 of each of said guide portions 24, 26 is greater than the distance separating the outlet ends 30 of said guide portions 24, 26.

[0064] A cut-off plane 50, here transverse and longitudinal, extends between the two guide portions 4, 6. As illustrated in FIG. 4, the optical element 20 is arranged in the light module such that the optical axis of the light module is inscribed in this cut-off plane 50. The cut-off plane partitions the optical element into two distinct zones, including an upper zone, comprising the first guide portion, an upper part of the terminal portion 32 and an upper part of the exit face 34, and a lower zone, similarly comprising the second guide portion, a lower part of the terminal portion 32 and a lower part of the exit face 34.

[0065] The output ends 30 of the first guide portion 24 and the second guide portion 26 are separated from each other by a cutting edge 36, formed at the junction of the two guide portions.

[0066] The cutting edge 36 extends substantially transversely, as seen in Figure 6 in particular. In the illustrated embodiment, the cutting edge has, substantially in its center, a recess or projection, which separates the cutting edge into two parts vertically offset from each other. Such that will be detailed below, this makes it possible to generate a cut-off of the beam with a step. Of course, this is only an example of the embodiment of the cut-off edge 36, which in an alternative embodiment may not have said drop or projection.

[0067] More specifically, the cutting edge 36 has, in the longitudinal-vertical section plane, a curvature whose radius of curvature is less than 0.3 mm, preferably less than or equal to 0.1 mm. It is understood that the curvature of the cutting edge 36 is necessary for producing the part by injection but that having the smallest possible radius of curvature makes it possible to form a clean edge all along the cutting edge 36.

[0068] As a result, the distance separating the outlet ends 30 of the first and second guide portions 24, 26 is at most 0.6 mm, this distance being, as mentioned previously, less than the distance separating the inlet ends 28 of said guide portions 24, 26. The distances separating the ends of the first guide portion 24 and the second guide portion 26 as mentioned above are measured along the vertical direction and consist of the shortest segment joining the first guide portion 24 to the second guide portion 26 at the ends concerned.The distance separating the inlet ends 28 is thus measured between the part of the inlet end of the first portion closest to the cut-off plane 50 and the part of the inlet end of the second portion closest to the cut-off plane 50 and the distance separating the outlet ends 30 is thus measured between the part of the outlet end of the first portion closest to the cut-off plane 50 and the part of the outlet end of the second portion closest to the cut-off plane 50.

[0069] As is also more visible in Figure 6, the optical element 20 comprises a clearance of material 38 which separates the first guide portion 24 and the second guide portion 26. This clearance of material 38 is formed from a face opposite the exit face 34 of the optical element 20 and it therefore extends opposite the terminal portion 32 of the light guide 22.

[0070] The optical element 20 is intended to be arranged opposite the printed circuit board 8 which forms a support for the first light source 14 and the second light source 16. The first light source 14 and the second light source 16 are arranged on the printed circuit board 8 in the same plane, which is parallel to the plane in which the input ends 28 of the first and second guide portions 24, 26 extend. It should be noted that alternatively, without departing from the context of the invention, it could be provided that each light source associated with a guide portion is arranged on a printed circuit board dedicated to this light source and arranged in a plane different from that in which the other light source extends, these planes each being able to be inclined relative to the plane in which the cut-off edge is inscribed.

[0071] Furthermore, the light rays emitted by the first light source 14 and by the second light source 16 enter the associated guide portions 24, 26 by being made parallel to each other by collimators 40, visible in particular in FIGS. 3 and 6.

[0072] Figure 4, which is a sectional view of the light module 2 along the sectional plane shown in Figure 3, makes it possible to schematically illustrate the propagation of the light rays 42 emitted by the first light source 14 and passing through the optical element 20.

[0073] The first light source 14 emits a plurality of light rays 42 which are collimated by a plurality of collimators 40, each collimator 40 being arranged longitudinally facing a light-emitting diode 18 participating in forming the first light source 14. As visible in FIG. 4, the light rays 42, which have been collimated beforehand, enter the first guide portion 24 while being substantially parallel to each other.

[0074] These light rays 42 reach a first reflecting surface 44 of the first guide portion 24 arranged longitudinally directly opposite the collimators 40. Said first reflecting surface 44 forms a first wall of the optical element 20 at the level of the entry end 28 of the first guide portion 24. The orientation of this first reflecting surface is such that the angle of incidence of the light rays 42 reaching this first reflecting surface 44 generates a total internal reflection of these light rays 42.

[0075] The light rays 42 reflected by the first reflecting surface 44 reach a second reflecting surface 46 of the first guide portion 24. This second reflecting surface 46 of the first guide portion 24 forms a second wall of the first guide portion 24 opposite the first wall formed by the first reflecting surface 44. More specifically, the second reflecting surface 46 forms a wall delimiting the first guide portion 24 and the material clearance 38.

[0076] Like the light rays 42 reaching the first reflecting surface 44, the light rays 42 reaching the second reflecting surface 46 are completely reflected. A majority of these light rays 42 are reflected towards the exit face 34 of the optical element 20. However, certain light rays 42 are reflected towards a cut-off wall 48 extending mainly longitudinally and transversely.

[0077] This cut-off wall 48 extends the second reflecting surface 46 and is bordered longitudinally by this second reflecting surface 46 and by the cut-off edge 36. The light rays 42 reaching this cut-off wall 48, including the cut-off ray 42a visible in FIG. 4, are, in the embodiment shown, reflected in the direction of the exit face 34 of the optical element 20, in particular in an upper part of this exit face. It should be noted that in an alternative embodiment of the invention, this cut-off wall 48 may have a coating preventing the reflection of the light rays.

[0078] The light rays 42 exiting the optical element 20 via the exit face 34 reach the projection lens 4, which has an optical axis which may in particular lie within the cut-off plane 50 passing through the cut-off edge 36 and the cut-off wall 48. Furthermore, the projection lens 4 has an object focus arranged on or substantially on the cut-off edge 36 of the optical element 20. Alternatively, the cut-off wall 48 may have a slight inclination relative to the cut-off plane 50.

[0079] The light rays 42 which have propagated in the optical element so as to pass through the exit face 34 in its upper part tend to exit the projection lens below the cut-off plane 50. It is understood that the cut-off wall 48 makes it possible to block the light rays 42, in particular after their reflection by the second reflective surface 46 of the first guide portion 24, which would be caused to form an upper part of the first light function too high on the regulatory photometric grid of a dipped beam type lighting function.

[0080] The projection lens 4 has a height less than or equal to 45 mm, that is to say a vertical dimension, perpendicular to the optical axis and here to the cut-off plane, which is at most equal to 45 mm. This dimension of the projection lens 4 allows a reduced size of the light device and it is made possible in particular by the vertical compactness of the optical element 20. Indeed, the first guide portion 24 and the second guide portion 26 are respectively arranged so that the entry face of the light rays of each of the guide portions is arranged substantially vertically, with the associated light sources which are offset longitudinally relative to these entry faces, opposite the projection lens.The presence of the light sources, and the associated collimators, at the rear of the optical element 20, thus enlarges the light module along the longitudinal component, parallel to the optical axis, but has no impact on the vertical dimension, which makes it possible to optimize the vertical compactness of the light module and the projection lens.

[0081] As mentioned previously, the light rays 42 constituting the first light beam passing through the optical element 20 through the first guide portion 24 are intended to form the first light function which is of the dipped beam type. This first light beam must have an upper cut-off so that the first light function does not dazzle other road users. This upper cut-off is achieved by the cut-off edge 36 and the cut-off wall 48.

[0082] The fineness of the cut-off edge 36 makes it possible to form the upper cut-off of the first light beam very clearly, and the cut-off wall 48 blocks the light rays which would be caused to be projected by the projection lens above said upper cut-off of the first light beam.

[0083] Figure 5 shows the same sectional view of the light module 2 as the sectional view visible in Figure 4. In the schematic representation offered by Figure 5, the first light source 14 and the second light source 16 emit light rays 42, respectively in the first guide portion 24 and in the second guide portion 26.

[0084] The second light source 16 is, as mentioned above, intended to participate in the formation of the second light function. More particularly, in the embodiment shown, the second light function participates in the formation of a regulatory lighting function, of the high beam type. For this purpose, the second light function is a complementary high beam type lighting function making it possible to form, in combination with the first light function, the formation of the high beam type lighting function. This high beam type lighting function is ensured by the joint emission of light rays by the first light source 14 and by the second light source 16, that is to say by the combination of the first light function and by the second light function.For this purpose, the light rays 42 emitted by the first light source 14 and the light rays 42 emitted by the second light source 16 simultaneously pass through the optical element 20 so as to together form the main beam type lighting function. It is understood that the light rays 42 emitted by the second light source 16 are intended to supplement the first light function formed by the light rays 42 emitted by the first light source 14 to form the main beam type lighting function.

[0085] It should be noted that, similarly to what has just been described previously, the first light function and the second light function may participate in combination in the formation of a dipped beam type lighting function. For this purpose, the first light function may form the upper part of the dipped beam type lighting function on a regulatory grid by means of the upper cut-off of the first light beam. For example, the first light beam may be a narrow light beam with an upper cut-off provided with a projection. The second light function may form the lower part of the dipped beam type lighting function on said regulatory photometric grid. For example, the second light beam may be a wide light beam with a horizontal upper cut-off, without a projection.

[0086] Like the light rays emitted by the first light source 14, the light rays 42 emitted by the second light source 16 are collimated by collimators 40 arranged projecting from an entry face of the second guide portion 26. It should be noted that to facilitate the visibility of FIG. 5 and in particular of the light ray tracings, the light rays emitted by the second light source 16 are represented by dotted lines that are tighter than the dotted lines representing the light rays emitted by the first light source 14.

[0087] The light rays 42 emitted by the second light source 16 and collimated by the collimators 40 reach a third reflecting surface 52 of the second guide portion 26, arranged opposite the entry face of the light rays and the collimators. Like the light rays 42 reaching the first and second reflecting surfaces 44 and 46, the light rays 42 reaching the third reflecting surface 52 are completely reflected. More precisely, these light rays 42 reflected by the third reflecting surface 52 are reflected in the direction of a fourth reflecting surface 54 arranged in the second guide portion 26 and which delimits on the one hand this second guide portion 26 and on the other hand the material clearance 38.

[0088] The light rays 42 reaching the fourth reflecting surface 54 are once again completely reflected, and this in the direction of the exit face 34 of the optical element 20 until they reach the projection lens 4. The inclination of the reflecting surfaces of the second guide portion is such that the light rays emanating from the light source associated with the second guide portion 26 are directed onto the entire exit face 34, as can be seen in particular in FIG. 5.

[0089] In this way, when the light sources associated with the two guide portions are selectively activated, light rays exit the optical element over the entire surface of the exit face 34 and the projection lens 4 is caused to project a wide light beam, without horizontal cut-off.

[0090] As is remarkable, in particular in this figure 5, the fourth reflecting surface 54 of the second guide portion 26 extends to the cut-off edge 36. It is understood that the cut-off edge 36 is delimited on one side by the fourth reflecting surface 54 and on the other side by the cut-off wall 48.

[0091] Figure 6 represents a perspective view of the optical element 20, seen from the rear opposite the exit face, this view making it possible in particular to highlight the collimators 40 of the optical element 20 and the release of material 38.

[0092] The material clearance 38 is a hollow formed in the material from the rear face 200 of the optical element, this rear face 200 forming the entry face of the first guide portion 24 and the entry face of the second guide portion 26. The material clearance 38 has an asymmetrical shape on either side of the cut-off plane previously mentioned, being delimited by at least one wall also delimiting the first guide portion and at least one wall delimiting the second guide portion. In the embodiment shown, the material clearance is delimited by at least three walls including the wall forming the second reflective surface, the cut-off wall and the wall forming the fourth reflective surface.

[0093] As seen in Figure 6, the cut-off wall 48 is perpendicular to the plane of the input surface 200, the plane from which the collimators 40 extend. In connection with Figure 2, it is notable that, as mentioned previously, the printed circuit board 8 forms a support for the light-emitting diodes 18 of each light source 14, 16, each light-emitting diode being supported so as to be opposite a collimator 40. In the illustrated example, the collimators, and therefore the light-emitting diodes, are aligned for the first light source 14 and the associated first guide portion 24, while they have a pattern on several levels for the second light source 16 and the associated second guide portion 26, without this example of arrangement being limiting of the invention. It is understood that the cut-off wall 48 is then perpendicular to the plane of the light-emitting diode support.Of course, in accordance with what has been described previously, the cutting wall 48 may have a slight inclination relative to a plane perpendicular to the plane of the support.

[0094] As seen in Figure 6, the cut-off wall 48 may have a recess 56 which is intended to form at the level of the upper cut-off of the first light beam a vertical offset on one side relative to the other of the cut-off of the beam generating the first light function.

[0095] The invention as described achieves the aim it set itself and makes it possible to propose, in the context of a light module intended to equip a motor vehicle and capable of generating two distinct light functions on the same lighting surface, an optical element configured so as to be able to reduce the vertical size of the light module and in particular the vertical size of a projection lens of this light module. In addition, such an organization also makes it possible to limit the size of the light module in a direction parallel to the direction of travel of the vehicle equipped with the light module by means of the reflection of the light rays within the guide portions of the light module.

Claims

CLAIMS 1. Optical element (20) of a light module (2) intended to equip a motor vehicle, the optical element (20) comprising a light guide (22) comprising at least a first guide portion (24) participating in the formation of a first light beam capable of performing at least a first light function and a second guide portion (26) participating in the formation of a second light beam capable of performing at least a second light function, the first light function being distinct from the second light function, the first guide portion (24) and the second guide portion (26) opening into an end portion (32) of the light guide (22), the junction between the first guide portion (24) and the second guide portion (26) forming a cut-off edge (36), the first light beam comprising an upper cut-off formed by the cut-off edge (36).

2. Optical element (20) according to claim 1, wherein the first guide portion (24) and the second guide portion (26) each comprise at least two reflective surfaces (44, 46, 52, 54) configured to totally reflect light rays (42) reaching said reflective surfaces (44, 46, 52, 54).

3. Optical element (20) according to any one of claims 1 and 2, wherein the optical element (20) comprises a clearance of material (38) which separates the first guide portion (24) from the second guide portion (26), opposite the terminal portion (32).

4. Optical element (20) according to claim 3, in which the first guide portion (24) is delimited by two successive intersecting walls of the material clearance (38) among which a cut-off wall (48), said cut-off wall being distinct from the two reflective surfaces (44, 46) of this first guide portion (24).

5. Optical element (20) according to claim 4, in which the cut-off wall (48) extends the second reflective surface (46) of the first guide portion (24), so that the cut-off wall (48) is longitudinally bordered by the second reflective surface (46) and by the cut-off edge (36).

6. Optical element (20) according to claim 4 or 5, wherein the cut-off edge (36) is formed by one of the two reflective surfaces (54) of the second guide portion (26) and by the cut-off wall (48) of the first guide portion (24).

7. Optical element (20) according to claim 5, wherein the optical element (20) comprises an exit face (34) through which light rays (42) are able to exit the optical element (20), the cut-off wall (48) being perpendicular, or substantially perpendicular, to the exit face (34).

8. Optical element (20) according to any one of claims 1 to 7, wherein the first guide portion (24) and the second guide portion (26) each have an input end (28) and an output end (30), the junction of the output ends (30) of said guide portions (24, 26) forming the cut-off edge (36), at least one collimator (40) being arranged at the input end (28) of the first guide portion (24) and at least one other collimator (40) being arranged at the input end (28) of the second guide portion (26).

9. Optical element (20) according to claim 8, wherein the input end (28) of the first guide portion (24) and the input end (28) of the second guide portion (26) are in the same plane.

10. Optical element (20) according to claims 7 and 9, wherein the plane in which the input end (28) of the first guide portion (24) and the input end (28) of the second guide portion (26) are located is parallel to the plane in which the output face (34) mainly extends.

11. Optical element (20) according to any one of claims 1 to 10, wherein the cut-off edge (36) has a radius of curvature of less than 0.3 mm.

12. Light module (2) comprising an optical element (20) according to any one of claims 1 to 11, the light module (2) comprising at least two light sources (14, 16) and a projection lens (4), at least one light source (14) being arranged opposite the first guide portion (24) and at least one light source (16) being arranged opposite the second guide portion (26), each light source (14, 16) being configured to emit light rays (42) into the associated guide portion (24, 26) of the optical element (20), the optical element (20) being configured to direct the light rays (42) towards the projection lens (4).

13. Light module (2) according to claim 12, wherein the projection lens (4) has an object focus arranged at the cut-off edge (36) of the optical element (20).

14. Light module (2) according to any one of claims 12 and 13, in which each light source (14, 16) of the light module (2) is arranged on the same support.

15. Light module (2) according to any one of claims 12 to 14, wherein the projection lens (4) has a height less than or equal to 45 mm, the first guide portion (24) and the second guide portion (26) being arranged one above the other in a vertical direction, said height being measured parallel to this vertical direction.

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