LIGHT MODULE WITH NETWORK OF REFLECTIVE SURFACES AND MICROLENS

Abstract

LIGHT MODULE WITH NETWORK OF REFLECTIVE SURFACES AND MICROLENS The invention relates to a light module (2), particularly for motor vehicles, comprising a light source (4) capable of emitting light rays; a device for redirecting light rays into guided light rays (6); reflective surfaces (8) configured to receive and reflect the redirected light rays into reflected light beams; projection lenses (10) associated with the reflective surfaces (8) so as to project the reflected light beams into overlapping projected light beams to form an overall light beam. (Figure to be published with the abbreviation: Figure 1)

Description

Title of the invention: LIGHT MODULE WITH A NETWORK OF REFLECTING SURFACES AND MICROLENSES Technical field

[0001] The invention relates to the field of lighting and light signaling, in particular for motor vehicles. Prior art

[0002] It is common to use light modules comprising an emitter of collimated light beams, an array of input lenses arranged in a matrix opposite the emitter of collimated light and an array of output lenses following said matrix. These two arrays are usually assembled to each other with a mask arranged between the two, said mask comprising an array of openings following the matrix and intended to form the edges of the light images thus produced. The production of such a mask, usually by lithography on glass, and its assembly with the two arrays of lenses can prove technically complex and expensive. Such a configuration is known in particular from patent document EP 3 608 586 AL Statement of the invention

[0003] The invention aims to overcome at least one of the drawbacks of the aforementioned prior art. More particularly, the invention aims to propose a lens array light module that is more economical and less bulky.

[0004] The subject of the invention is a light module, in particular for a motor vehicle, comprising a light source capable of emitting light rays; a device for reorienting the light rays into reoriented light rays; reflective surfaces configured to receive and reflect the reoriented light rays into reflected light beams; optical projection elements associated with the reflective surfaces so as to project the reflected light beams into projected light beams which are superimposed to form an overall light beam.

[0005] Advantageously, the reorientation device is configured to reorient the light rays by reflection along a main direction or by successive reflections.

[0006] Advantageously, the reorientation device is a guidance device.

[0007] Advantageously, the optical projection elements comprise projection lenses and / or surfaces or patterns on an output face of an optical part which may correspond to the reorientation device.

[0008] According to an advantageous embodiment of the invention, the reorientation device comprises an optical part made of transparent or translucent material with an entry face for the light rays and forming the reflective surfaces.

[0009] According to an advantageous embodiment of the invention, the optical part is a light guide extending in a main direction, preferably non-rectilinear, and comprising a lateral external surface ensuring guidance of the light rays by total reflection and comprising the reflective surfaces.

[0010] According to an advantageous embodiment of the invention, the reflective surfaces are formed by notches formed in a rear face of the light guide, the guided light rays reflected by said reflective surfaces exiting the light guide via a front face of said light guide, oriented towards the optical projection elements.

[0011] According to an advantageous embodiment of the invention, the reorientation device comprises a cap-shaped collector capable of reflecting the light rays towards the reflective surfaces.

[0012] According to an advantageous embodiment of the invention, the collector is made of transparent or translucent material and the input face of the optical part is coupled to an output of the collector.

[0013] According to an advantageous embodiment of the invention, the optical projection elements are integrally formed in the optical part.

[0014] According to an advantageous embodiment of the invention, the light rays reflected by the collector are transmitted to the reflecting surfaces via ambient air.

[0015] According to an advantageous embodiment of the invention, the optical projection element has a focus located on the associated reflective surface.

[0016] According to an advantageous embodiment of the invention, at least one of the reflecting surfaces has a downstream edge, relative to a direction and a main sense of propagation of the reoriented light rays, and the corresponding optical projection element has a focus located on the downstream edge so as to form with said downstream edge a cut-off edge of the corresponding projected light beam.

[0017] According to an advantageous embodiment of the invention, at least one of the reflecting surfaces has a downstream edge, relative to a direction and a main sense of propagation of the reoriented light rays, and the corresponding optical projection element has a focus located at a distance from the downstream edge so as to form a corresponding projected light beam without cutoff.

[0018] By "focus located on" we understand that this focus is located on said reflective surface, or on an image of said reflective surface, at a distance from said surface, in particular in the presence of an optical interface. In other words, in this case, the focus of the projection lens is located on the image of the reflective surface by the optical interface located between said reflective surface and said projection lens. Said interface may in particular be the face of the light guide through which the light exits said guide.

[0019] According to an advantageous embodiment of the invention, the light source is a first light source and the reflective surfaces are first reflective surfaces, the light module comprising a second light source arranged, relative to the reorientation device, opposite the first light source so that said reorientation device reorients light rays emitted by the second light source towards second reflective surfaces configured to receive and reflect said reoriented light rays into light beams reflected towards the projection lenses.

[0020] According to an advantageous embodiment of the invention, each of the second reflecting surfaces is adjacent to one of the first reflecting surfaces and has an inclination relative to a main direction of the reorientation device which is opposite to an inclination of the first adjacent reflecting surface relative to said main direction.

[0021] According to an advantageous embodiment of the invention, each of the second reflective surfaces is formed by the notch forming the first reflective surface adjacent to said second reflective surface.

[0022] The measures of the invention are advantageous in that they make it possible to produce a light module in the form of an array of lenses or microlenses with a reduced bulk along the main direction of the overall light beam produced. They also make it possible to produce a cut-off in the overall light beam without the use of masks with a cut-off edge, which otherwise often have to be produced by lithography on glass, which can be expensive and involve a certain bulk. The measures of the invention are advantageous in that they make it possible to produce a light module of potentially complex shape such as a curved shape, as illustrated in the first embodiment. Brief description of the drawings

[0023] [Fig. 1] is a perspective view of a light module according to a first embodiment of the invention;

[0024] [Fig.2] is a side view of the light module of [Fig.l];

[0025] [Fig.3] is a functional view of a portion of the light module of Figures 1 and 2 and images of the projected light beams;

[0026] [Fig.4] is a detailed perspective view of two notches according to a first configuration of the light module of Figures 1 to 3;

[0027] [Fig.5] is a detailed perspective view of two notches following a second configuration of the light module of figures 1 to 3;

[0028] [Fig.6] is a front view of a light module according to a second mode of realization of the invention;

[0029] [Fig.7] is a side view of the light module of [Fig.6];

[0030] [Fig.8] is a side view of the light module of [Fig.6], according to a variant;

[0031] [Fig.9] is a functional view of a portion of an optical part according to a variant applicable to the first and second embodiments of the invention. Detailed description

[0032] In the description which follows, and more generally in the context of the present invention, the notions of orientations such as “horizontal”, “vertical”, “lateral”, etc. are to be understood when the lighting module is in the normal mounting and operational position, as illustrated in the figures.

[0033] Figures 1 to 5 illustrate a first embodiment of the invention.

[0034] [Fig. 1] is a perspective view of a light module according to the first embodiment. The light module 2 comprises a light source 4, an optical part made of transparent or translucent material, in the form of a light guide 6, with an entry face 6.1 opposite which the light source 4 is arranged, and an external lateral surface 6.2 forming, with the ambient air, a diopter capable of reflecting by total reflection the light rays propagating in the light guide in its main direction. The light rays in question are thus reoriented and guided by the light guide 6. It should be noted that this is the very operating principle of a light guide, well known per se to those skilled in the art.

[0035] It can be observed that the outer lateral surface 6.2, more precisely a rear face 6.4, of the light guide 6 has notches 6.3 distributed along the light guide 6 and forming reflective surfaces 8. These are capable of receiving the light rays guided by the upstream part of the light guide and of reflecting them towards the front face 6.5, opposite the rear face 6.4, in reflected light beams. The latter exit via the front face 6.5, and are directed towards the projection lenses 10 and are projected by them in projected light beams.

[0036] [Fig. 2] is a side view of the light module of [Fig. 1]. It can be seen that each reflective surface 8 is associated with a projection lens 10. [Fig. 2] (as well as [Fig. 1]) shows in this case 7 reflective surfaces 8 and 7 corresponding projection lenses 10, it being understood that this number can be larger or smaller, depending on the desired overall light beam. Each reflective surface - projection lens assembly in fact forms a beam projected light, these different projected light beams overlapping (at least some of them) and combining to form an overall light beam.

[0037] [Fig. 3] is a detailed view of a portion of the light guide 6 of the light module 2 of [Fig. 2], said portion comprising one of the notches 6.3 and the reflective surface 8 formed by said notch 6.3, and of the projection lens 10 associated with said portion of the light guide.

[0038] The reflecting surface 8 advantageously has a limited inclination relative to the main direction (shown in dot-and-dash lines) of the corresponding portion of the light guide, so as to be able to ensure reflection of the light rays guided by total reflection. This inclination α is advantageously less than or equal to 30°. It is however also possible to provide a reflective treatment on the reflecting surface 8, such as metallization, in which case the inclination constraint detailed above does not apply. It should also be noted that the inclination of the reflecting surface also depends on the direction in which the reflected light beam is to be produced.The reflected light beams produced by the different reflecting surface - projection lens pairs are advantageously all essentially parallel, while the orientation of the light guide varies progressively along the light guide 6. The inclination of the reflecting surfaces therefore also depends on the geometry of the light guide.

[0039] The projection lens 10 conventionally comprises an entrance face 10.1 and an output face 10.2. It also comprises a focus 10.3 which is advantageously located on the reflecting surface 8, so as to project to infinity the image of the reflecting surface 8 in question, or at least a portion of said image. The focus 10.3 may be located on the downstream edge 8.1 of the reflecting surface, as represented by the continuous cross. By downstream edge 8.1, we mean the edge of the reflecting surface 8 located furthest downstream with respect to a direction and a main sense of propagation of the light along the light guide following its main direction. With such a configuration, the downstream edge 8.1 in question will be imaged sharply and will then form an upper horizontal cut-off in the corresponding projected light beam.Such a configuration is therefore particularly useful for forming a regulatory lighting function of the “code” or crossing type (also commonly referred to as “low-beam” in English). According to a variant, the focus 10.3' may be located at a distance from the downstream edge 8.1 and also from the upstream edge 8.2 (opposite the downstream edge 8.1), advantageously on the reflecting surface 8 in order to maintain a high intensity in the projected beam, as represented by the other cross, so as to image neither the downstream edge 8.1 nor the upstream edge 8.2. The focus 10.3' may be at a distance from the downstream edge 8.1 of at least 50% of the distance between the downstream edge 8.1. and the upstream edge 8.2, while also being at a distance from the upstream edge 8.2. The projected light beam thus produced then has no cut-off, either upper or lower, and can thus participate in the formation of a regulatory automotive lighting function of the “road” or “full beam” type (also commonly referred to as “high-beam” in English).

[0040] It should be noted that for reasons of simplification and clarity of presentation, the focus 10.3 of the projection lens 10 is shown on the reflecting surface 8, it being understood, however, that this focus may be located on the image of the reflecting surface 8, at a distance from said surface, in particular in the presence of an optical interface. In other words, the focus of the projection lens is located on the image of the reflecting surface by the optical interface located between said reflecting surface and said projection lens. In this example the interface corresponds to the front face 6.5.

[0041] The images of the projected light beams described above are represented schematically in the graph with the H and V axes of [Fig. 3], where the H axis represents the horizontal direction and the V axis the vertical direction, the intersection of the H and V axes corresponding essentially (to within 1°) to the optical axis of the reflective surface - projection lens pair in question. When the focus 10.3 is located on the downstream edge 8.1, the light image 12 of the projected light beam has a higher horizontal cut-off whereas when the focus 10.3' is at a distance from the downstream edge 8.1, the light image 12' does not have a horizontal cut-off. In this case, the image 12' partially overlaps the image 12, it being understood, however, that such a superposition is not obligatory and can be chosen depending on the way in which the overall light beam is constructed.

[0042] It will therefore be understood that the configuration and its variant illustrated in [Fig.3] and described above can be repeated as desired on the other reflective surface - projection lens pairs of the light module 2.

[0043] Figures 4 and 5 show two examples of embodiments of the notches 6.3 of the light guide 6.

[0044] [Fig. 4] shows in perspective the rear face 6.4 of the light guide 6, on a section thereof. Two notches 6.3 can be seen, in this case essentially identical, each forming a reflecting surface 8 with a non-rectilinear downstream edge 8.1, in this case forming two adjoining rectilinear portions, the left one of which is horizontal and the right one is inclined downwards. The light image thus produced is represented schematically in the graph comprising the H and V axes, similarly to the graph of [Fig. 3], in a configuration where the focus of the projection lens 10 is located on or near the downstream edge 8.1 in question, in particular near the point of intersection of the two rectilinear portions. It can be seen that the upper cut is inclined towards the top left and horizontal right, thus corresponding to the shape of the downstream edge 8.1, however subject to inversion when passing the projection lens.

[0045] [Fig.5] is a representation similar to [Fig.4], except that the downstream edge 8.1 is here rectilinear and horizontal. The light image produced, in a configuration where the focus of the projection lens 10 is located on or near the downstream edge 8.1 in question, in particular near the middle of said downstream edge, then has a generally horizontal and rectilinear upper cutoff.

[0046] Figures 6 to 8 illustrate a second embodiment of the invention.

[0047] [Fig.6] is a front view of a light module 102 according to the second mode of embodiment of the invention. The reference numbers of the first embodiment are used to designate identical or corresponding elements, these numbers being increased by 100. Reference is also made to the description of these elements in the context of the first embodiment.

[0048] In [Fig. 6], the light module 102 comprises a light source 104, reflective surfaces (not visible in [Fig. 6]) and projection lenses 110, similarly to the first embodiment. The light module 102 of this second embodiment differs from that of the first embodiment essentially in that the reorientation of the light rays emitted by the light source 104 towards the reflective surfaces is different and also in that the reflective surfaces and the projection lenses can be arranged in a matrix, more precisely in several parallel rows following the main direction of propagation of the light.

[0049] [Fig.7] is a side view of the light module 102 of [Fig.6]. It can be observe that the device for redirecting the light rays towards the reflective surfaces 108 comprises a collector 106.1, in the form of a cap, arranged in line with a main axis of light emission of the light source 104, and an optical part 106.2 made of transparent or translucent material. The latter comprises a light entry face 106.2.1 coupled to the exit of the collector 106.1. Thus, the light entry face 106.2.1 and the exit of the collector 106.1 are merged, so that there is a continuity of material between the collector 106.1 and the optical part 106.2. Also, the optical part 106.2 may have a parallelepiped shape or close to such a geometric shape. The reflective faces 108 are formed by notches 106.2.3 formed in a rear face 106.2.4 of the optical part 106.2, similarly to the first embodiment.Similar to the first embodiment, the reflective surfaces may reflect the guided light rays by total reflection or by applying a reflective coating, depending in particular on the general geometry of the light module. Similar to the first embodiment, some of the reflective surfaces 108 may, by virtue of their . inclination relative to the light rays guided towards them, be reflective by total reflection while others may be provided with a reflective coating.

[0050] The projection lenses 110 are in this case integrally formed with the optical part 106.2, it being understood, however, that they may be distinct from the optical part 106.2.

[0051] The reflective surfaces 108 can be distributed in several rows parallel to the main direction of propagation of the light, this direction being vertical according to the orientation of [Fig.7]). For this purpose, the collector 106.1 has a reflective surface of generally parabolic profile with a focus located at the light source 104, so as to guide the light rays homogeneously on all the reflective surfaces 108 arranged in a network or matrix.

[0052] Similar to the first embodiment, some of the projection lenses may have a focus located on or near a downstream edge of the reflecting surfaces or, alternatively, at a distance from said downstream edge and the upstream edge, depending on the presence of a cut-off or unwanted in the corresponding projected light beam.

[0053] Similar to the first embodiment, the projected light beams produced by the different reflective surface - projection lens pairs combine by complementing and / or superimposing each other.

[0054] [Fig.8] is seen similar to [Fig.7], namely a side view of the light module 102 of [Fig.6], however according to a variant.

[0055] It can be observed that unlike [Fig.7], the light module 102' does not include an optical part. The optical surfaces 108' are then formed by reflective physical supports, the light rays guided by reflection by the collector 106' propagating to the reflective surfaces in ambient air. The reflective physical supports have a reflective surface, in particular metallized, as opposed to the principle of total reflection such as in the light guide of the first embodiment.

[0056] [Fig.9] is a functional view of a portion of an optical part provided with a notch, applicable to the first and second embodiments of the invention.

[0057] [Fig. 9] is similar to [Fig. 3], except that the notch 6.3, 106.3 forms in the optical part 6, 106 a second reflecting surface 14, 114, adjacent and opposite to the first reflecting surface 8, 108. The light module 2, 102 then comprises a second light source 5, 105 located at an entry face of the optical part 6, 106 opposite to that facing the first light source 4, 104. The rays emitted by the second light source propagate in the optical part in a direction opposite to that of the light rays emitted by the first light source. These rays are incident on the second surface reflecting 14, 114 and reflected to form a second projected light beam. This second projected light beam may not have a cut-off and thus participate in the formation, with the other projected light beams, of an overall light beam without horizontal cut-off, such as a regulatory automotive lighting function of the “road” or “full headlight” type (also commonly referred to as “high-beam” in English).

[0058] In the case where the variant described above is applied to the second embodiment, such as in figures 6-8, the second light source 105 is associated with a second collector, in particular in the form of a cap, similar to the collector 106 or 106'. Also, the second reflective surfaces 114 or 114' are then formed on the rear entry face 106.2.4 of the optical part 106.2 ([Fig.7]) or on the reflective physical supports forming the first reflective surfaces 108' ([Fig.8]).

Claims

Claims

1. Light module (2; 102; 102'), in particular for a motor vehicle, comprising: - a light source (4; 104; 14') capable of emitting light rays; - a device (6; 106; 106') for reorienting the light rays into reoriented light rays; - reflective surfaces (8; 108; 108') configured to receive and reflect the reoriented light rays into reflected light beams; - optical projection elements (10; 110) associated with the reflective surfaces (8; 108; 108') so as to project the reflected light beams into projected light beams which overlap to form an overall light beam.

2. Light module (2; 102) according to claim 1, wherein the reorientation device (6; 160) comprises an optical part (6; 106.2) made of transparent or translucent material with an entry face (6.1; 106.2.1) for the light rays and forming the reflective surfaces (8; 108).

3. Light module (2) according to claim 2, in which the optical part is a light guide (6) extending in a main direction, preferably not rectilinear, and comprising an external lateral surface (6.2) ensuring guidance of the light rays by total reflection and comprising the reflective surfaces (8).

4. Light module (2) according to claim 3, wherein the reflective surfaces (8) are formed by notches (6.3) formed in a rear face (6.4) of the light guide (6), the guided light rays reflected by said reflective surfaces (8) exiting the light guide (6) via a front face (6.5) of said light guide, oriented towards the optical projection elements (10).

5. Light module (102; 102') according to one of claims 1 and 2, in which the reorientation device (106; 106') comprises a collector (106.1; 106') in the form of a cap and capable of reflecting the light rays towards the reflective surfaces (108).

6. A light module (102) according to claim 5 and according to claim 2, wherein the collector (106.1) is made of transparent or translucent material and the input face (106.2.1) of the optical part (106.2) is coupled to an output of the collector (106.1).

7. The light module (102) of claim 6, wherein the projection optical elements (110) are integrally formed in the optical part (106.2).

8. A light module (102') according to claim 5 dependent solely on claim 1, wherein the light rays reflected by the collector (106') are transmitted to the reflective surfaces (108') via ambient air.

9. Light module (2; 102; 102') according to one of claims 1 to 8, in which at least one of the reflecting surfaces (8; 108; 108') has a downstream edge (8.1), relative to a direction and a main sense of propagation of the guided light rays, and the corresponding optical projection element (10) has a focus (10.3) located on the downstream edge (8.1) so as to form with said downstream edge a cut-off edge of the corresponding projected light beam.

10. Light module (2; 102; 102') according to one of claims 1 to 9, in which at least one of the reflecting surfaces (8; 108; 108') has a downstream edge (8.1), relative to a direction and a main sense of propagation of the reoriented light rays, and the corresponding optical projection element (10) has a focus (10.3') located at a distance from the downstream edge (8.1) so as to form a corresponding projected light beam without cutoff.

11. Light module (2; 102; 102') according to one of claims 1 to 10, wherein the light source (4; 104; 104') is a first light source and the reflective surfaces (8; 108; 108') are first reflective surfaces, the light module comprising a second light source (5; 105) arranged, relative to the reorientation device (6; 106; 106'), opposite the first light source (4; 104; 104') so that said reorientation device reorients light rays emitted by the second light source (5; 105) towards second reflective surfaces (14; 114) configured to receive and reflect said reoriented light rays into reflected light beams towards the projection optical elements (10; 110).

12. A light module (102') according to claim 11, wherein each of the second reflective surfaces (14; 114) is adjacent to one of the first reflective surfaces (8; 108; 108') and has an inclination relative to a main direction of the reorientation device (6; 106; 106') which is opposite to an inclination of the adjacent first reflective surface (8; 108; 108') relative to said main direction.

13. A light module (2) according to claim 4 and claim 12, wherein each of the second reflective surfaces (14) is formed by the notch (6.3) forming the first reflective surface (8) adjacent to said second reflective surface (14).

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