Luminous system for a motor vehicle

Abstract

The invention relates to a luminous system (7) for a vehicle (1) configured to project information onto a surface (3) associated with the vehicle (1), the luminous system (7) being characterised in that an image (IP) of a reflected light beam (FR) projected onto a scattering element (11) has: - a first dimension (L1) in a first direction (D1) secant with the surface (3) associated with the vehicle (1), - a second dimension (L2) in a second direction (D2) parallel to the surface (3) associated with the vehicle (1), the second dimension being significantly larger than the first dimension.

Description

Automotive Lighting System

[0001] The present invention relates to the field of optoelectronics and finds particular application in the automotive industry. More specifically, it relates to lighting systems integrated into vehicles for the performance of signaling and / or decorative lighting functions.

[0002] These lighting systems, used for both interior and exterior vehicle illumination, project light onto various vehicle-related surfaces to form, for example, pictograms. On the exterior, they can be used for aesthetic purposes, such as passenger welcome animations, or for safety signaling functions, such as projecting open door warnings or parking guidelines onto the ground. Inside, they can be deployed to enhance the vehicle's aesthetics by generating decorative patterns, for example, on the dashboard, and also to improve safety by projecting informative pictograms, such as alerts for hazardous driving situations, into the driver's field of vision.

[0003] These lighting systems are typically mounted on the vehicle and can be angled relative to the surface they are mounted on, particularly when projecting light onto the ground. For example, in this case, the lighting system is installed vertically above the ground, so the beam of light is projected at an angle to the ground and to the vertical. This angle is necessary to direct the beam of light towards a desired projection area, while integrating the lighting system into the vehicle's bodywork, without placing it directly above that area.

[0004] However, this tilt leads to a degradation in the quality of the projected pictogram, caused by distortions or blurring related to the angle of incidence of the light rays on the surface. This phenomenon, called glare, transforms a square image emitted by the lighting system into a rectangular image on the ground, thus distorting the pictogram. This results in a poor-quality projected pictogram, impairing its usefulness or aesthetic appeal.

[0005] The present invention solves this problem by proposing a lighting system configured to manage the grazing phenomenon, which makes it possible to avoid the formation of a distorted image on the associated surface and thus guarantees the projection of a good quality pictogram.

[0006] The objective of the invention described in this document is therefore to overcome the drawbacks of the prior art by presenting a vehicle lighting system configured to project information onto a surface associated with said vehicle, the lighting system comprising: light emission means, each of the light emission means being configured to form a collimated light beam, a pivoting mirror device, a diffusion element, a beam mixing means configured to combine the collimated light beams into an overall light beam directed towards said pivoting mirror device, the latter being capable of being controlled to reflect the overall light beam into a reflected light beam oriented towards an entrance face of said diffusion element, which is configured to diffuse the reflected light beam into a projected light beam capable of being projected by a projection element towards the surface associated with the vehicle.

[0007] characterized in that an image of the reflected light beam presents on the entrance face of the diffusion element: a first dimensioning in a first direction secant to the surface associated with the vehicle, a second dimensioning in a second direction parallel to the surface associated with the vehicle, said second dimensioning being significantly larger than the first dimensioning.

[0008] By "significantly larger," we mean that the difference between the value of the first dimension and the value of the second dimension is at least 25% of the value of the first dimension. This is intended to distinguish the system from those in which the beam image on the entrance face of the diffusion element exhibits a shape with different dimensions due to manufacturing and assembly tolerances.

[0009] The surface associated with the vehicle can be an interior surface of the vehicle or, for example, the ground on which the vehicle rests. Thus, the lighting system can be used in interior lighting applications or in signaling applications, such as road markings.

[0010] The beam mixing method allows collimated light beams to be combined to form an overall light beam. To this end, it can include various devices, notably dichroic mirrors, configured to allow certain wavelengths to pass through while reflecting others.

[0011] At the output of the beam mixing device, the overall light beam can be collimated towards the pivoting mirror device. This collimation can be achieved using a collimation device positioned between the beam mixing device and the pivoting mirror device.

[0012] The pivoting mirror device, for its part, can include one or more pivoting mirrors. Each of these mirrors is designed to oscillate in such a way as to reflect the overall light beam, thus generating a reflected light beam that is converged towards a diffusion element.

[0013] This reflected light beam forms the image on the entrance face of the diffusion element. This diffusion element then diffuses the image by emitting the light beam in several directions around an optical axis of the light system. The diffusion element is translucent and has a visible light transmission rate greater than 90%, preferably greater than 95%.

[0014] The diffused light beam is then projected by the projection element onto the associated surface. It should be noted that the projection element is part of the lighting system according to the invention.

[0015] The term "image" here refers to the luminous shape formed by the light beam reflected off the diffusion element. To form the pictogram on the associated surface, the light beam moves, notably thanks to the pivoting mirror device, which causes the image to move across the surface. This movement, resulting in a succession of images, combined with the effect of retinal persistence, allows the pictogram to be formed on the associated surface.

[0016] When the lighting system is inclined relative to the ground and to the vertical, as in this case, the optical axis intersects the associated surface at a non-zero angle of incidence. This angle of incidence represents the angle formed between the optical axis and a normal to the surface associated with the vehicle.

[0017] It should be noted that the "first direction" defined earlier is both perpendicular to the optical axis and secant to the associated surface. As for the "second direction," it is also perpendicular to the optical axis, but parallel to the associated surface and perpendicular to the first direction.

[0018] The rays of the projected light beam, projected around the optical axis, also have an angle of incidence with the associated surface. The greater this angle, the more the projected image is distorted due to the phenomenon of glancing. More specifically, glancing has the effect of stretching the projected image in a direction parallel to the orthogonal projection of the optical axis onto the associated surface.

[0019] To avoid this distortion, the invention anticipates the phenomenon of glancing. To this end, the lighting system is configured so that the image projected onto the input face of the diffusion element is rectangular, with the shorter side of the rectangle corresponding to a first dimension in the first direction, and the longer side of the rectangle corresponding to a second dimension in the second direction. When the stretching due to glancing occurs in the direction parallel to the orthogonal projection of the optical axis, the image projected onto the associated surface then takes the form of a square, thus producing a high-quality pictogram without distortion.

[0020] According to an optional feature of the invention, a ratio between the first dimensioning and the second dimensioning is between 0.015 and 0.8.

[0021] The ratio is calculated by dividing the first dimensioning by the second dimensioning.

[0022] According to an optional feature of the invention: the first dimensioning of the image of the reflected light beam projected onto the diffusion element is between 5 and 100 µm, the second dimensioning of the image of the reflected light beam projected onto the diffusion element is between 60 and 300 µm.

[0023] These image size values ​​for the light beam projected onto the input face of the diffusion element are particularly well-suited to applications involving the projection of a pictogram onto the ground beneath the vehicle. These values ​​ensure optimal pictogram quality within a high-definition projection zone, which can be located between 0.3 and 1.5 meters from the vehicle, for a lighting system mounted on the vehicle at a height between 0.1 and 0.5 meters.

[0024] As a non-limiting example, when the high-definition projection area is located at a distance of 0.9 m from the vehicle, with a light system mounted on the vehicle at a height of 0.27 cm and a module tilt angle of 16°, the first dimensioning can be 15 µm and the second dimensioning 120 µm.

[0025] According to an optional feature of the invention, at least one of the means of light emission comprises: a light source configured to emit a light beam, a first collimating lens and a second collimating lens, configured respectively to collimate the light beam in the first direction and to collimate the light beam in the second direction, in order to form the collimated light beam.

[0026] Thus, the light source is configured to emit a light beam that is only partially or not at all collimated. This light beam is then collimated in the first and second directions by the first collimating lens and the second collimating lens, which allows it to be given the desired shape, thus enabling the image projected onto the diffusion element to have the desired rectangular shape.

[0027] In other words, collimating lenses adjust the beam opening angles to achieve the desired dimensions of the image projected onto the diffusion element.

[0028] The light source can be a laser emission source.

[0029] According to an optional feature of the invention, the light source has:

[0030] - a first dimension in the first direction,

[0031] - a second dimension in the second direction, larger than the said first dimension,

[0032] a ratio between the first dimension and the second dimension being between 0.005 and 0.3, the ratio being calculated by dividing the first dimension by the second dimension.

[0033] These dimensions give the light source a rectangular shape, which helps to produce a rectangular image projected onto the entrance face of the diffusion element. This configuration helps to anticipate the glare phenomenon, using the shape of the projected image to compensate for distortions caused by this phenomenon.

[0034] It is also worth noting that the dimensions of the light source can influence the divergence of the light rays emitted by the beam. Indeed, in some cases, the smaller the dimensions of the light source, the more divergent the light rays of the beam, and conversely, the larger the dimensions of the light source, the less divergent the light rays.

[0035] Thus, since the first dimension of the light source is smaller than the second dimension, the light rays of the light beam exhibit a greater divergence in the first direction than in the second direction.

[0036] According to an optional feature of the invention:

[0037] - the first dimension of the light source is between 0.5 and 4 µm,

[0038] - the second dimension of the light source is between 15 and 90 µm.

[0039] These dimensions of the light source are particularly suitable to allow obtaining, after projection onto the diffusion element, an image with a first dimension between 5 and 100 µm and a second dimension between 60 and 300 µm.

[0040] It should be noted that these dimensions are intrinsically linked to the specific characteristics of the laser source, particularly its color.

[0041] According to an optional feature of the invention, the first collimating lens is arranged between the light source and the second collimating lens.

[0042] By being placed between the light source and the second collimating lens, the first collimating lens is therefore closer to the light source than the second collimating lens.

[0043] This is because the light rays are more divergent in the first direction, and therefore, to recover a maximum of these light rays and collimate them effectively, the first collimating lens should be positioned closer to the light source than the second collimating lens.

[0044] According to an optional feature of the invention, said lighting system comprises a red light emission means, a green light emission means, and a blue light emission means, each comprising:

[0045] - a light source configured to emit a beam of light of the corresponding color,

[0046] - a first collimation lens configured to collimate the light beam in the first direction,

[0047] - a second collimation lens configured to collimate the light beam in the second direction.

[0048] In other words, the lighting system is an RGB (Red, Green, Blue) system, capable in particular of producing white light by combining these three colors.

[0049] Each means of light emission thus includes a light source and two collimating lenses, so that the image projected onto the entrance face of the diffusion element is rectangular, as defined previously, in order to anticipate the phenomenon of grazing.

[0050] According to an optional feature of the invention, a focusing distance extends between the second collimating lens and the light source of each of the light-emitting means, the focusing distance of at least two of the light-emitting means being different.

[0051] This difference in focusing distance can depend, in particular, on the different second dimensions of the light source for each light emission method. Indeed, the larger the second dimension of the light source, the larger the beam of light it generates in the second direction. Thus, depending on the desired shape of the projected image, the collimating lens is positioned at an appropriate focusing distance to collect more or fewer light rays, thereby controlling the size of the light beam in that second direction.

[0052] According to an optional feature of the invention, a collimation distance extends between the first collimation lens and the light source of each of the light-emitting means, the collimation distance of at least two of the light-emitting means being equal.

[0053] The collimation distance is essentially the same for each light-emitting device, because the first dimension of the light sources for each device is relatively close. Consequently, the divergence in the first direction is also essentially the same, which means that the first collimation lenses are positioned at the same distance to efficiently collect the diverging light rays in that first direction.

[0054] The invention also relates to a motor vehicle equipped with a lighting system as described in this document, said lighting system being configured to project information onto a ground on which the vehicle rests.

[0055] The lighting system, as described above, is particularly effective for projecting pictograms onto the ground from a motor vehicle, since it compensates for the glare phenomena often observed in this case.

[0056] Other features, details and advantages of the invention will become clearer upon reading the following description on the one hand, and the illustrative and non-limiting examples of embodiments given with reference to the attached drawings on the other hand, in which:

[0057] is a top view of a motor vehicle equipped with a lighting system according to the invention;

[0058] is a schematic representation of the lighting system illuminating a surface associated with the motor vehicle;

[0059] is a schematic diagram of the lighting system as defined in the invention;

[0060] represents a schematic diagram of the isolated light emission modules of the light system, in a plane perpendicular to a first direction;

[0061] is a schematic diagram of an isolated light emission module, in a plane perpendicular to a second direction;

[0062] is a schematic representation of a diffusion element isolated from the lighting system, notably making the entrance face of this diffusion element visible.

[0063] The features and variants 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 the features described below, isolated 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, elements common to several figures retain the same reference.

[0065] This is a top view of a motor vehicle 1 equipped with a lighting system according to the invention.

[0066] The lighting system (not visible in this figure) is designed to project information, such as a light pictogram, onto a surface associated with vehicle 1.

[0067] The surface associated 3 with the motor vehicle 1 can, for example, be an interior surface of the vehicle 1, in the context of an interior lighting application, or a floor 5 on which the vehicle 1 rests, in the context of a signaling application with road marking 5.

[0068] In the illustrated embodiment, the lighting system is configured to project a light pictogram onto the ground 5 where vehicle 1 rests, and more particularly, to project the light pictogram onto a general projection area ZG represented by a dotted line on the diagram which is located along vehicle 1, opposite the doors of the latter, so that the projected pictogram is visible to an observer located next to the doors.

[0069] The general projection zone ZG extends from the lighting system to an end edge whose distance from the car depends on the range of the lighting system. Near vehicle 1, it includes a high-definition projection zone ZH, which corresponds to an area where the aim is to obtain the sharpest possible pictogram. Therefore, the quality of the illuminated pictogram projected by the lighting system must be high in this area.

[0070] However, to project the illuminated pictogram, the lighting system is generally installed on the vehicle 1, and therefore in a vertical position above the ground 5, so that a beam of light is projected at an angle to the ground 5 and to the vertical. This angle allows the projected beam of light to be directed towards the desired high-definition projection area ZH, while having a lighting system integrated into the body of the vehicle 1 and not positioned directly above the high-definition projection area ZH. However, this results in a degradation of the quality of the projected pictogram due to distortions or blurring caused by this angle of the lighting system relative to the surface 3 associated with the vehicle 1, which will be illustrated in more detail later.

[0071] It should be noted that the lighting system, as described below, includes an output diffusion element. This diffusion element diffuses the image generated by the lighting system, projecting it in various directions around an optical axis of the system. More specifically, the diffusion element can be positioned at the focal point of a projection element within the lighting system. In this way, the image diffused by the diffusion element is then projected onto the associated surface by the projection element. For example, the diffusion element can be positioned between two projection lenses.

[0072] This is a schematic representation of the lighting system 7 illuminating the surface associated 3 with the motor vehicle 1.

[0073] The floor 5 is represented by a line on this figure, while the light system 7 is symbolized by a rectangle, with a light source configured to emit light rays forming an image IP on an input face of the diffusion element 11 at the output of the light system 7 as previously introduced, the diffusion element 11 being configured to diffuse a projected light beam FP, corresponding to the diffusion of the image IP, which is then projected towards the general projection area ZG of the floor 5 by means of a projection element 32, such as one or more projection lenses.

[0074] The IP image is a luminous shape formed by the light beam on the diffusion element 11 as a function of an angular position of a pivoting mirror device of the light system 7. The pictogram displayed on the associated surface 3 thus corresponds to a shape formed by the displacement of the image of this projected light beam FP on the ground 5 via the diffusion element 11 and the projection element 32, the displacement of the image being carried out by the pivoting mirror device.

[0075] When light rays are directed onto a surface associated with the vehicle 1 substantially perpendicular to the optical axis A of the light system 7, such as that illustrated in dotted lines on (reference 13), the images of the light source which are thus projected are without distortion, the angle of incidence α being substantially zero.

[0076] However, here, the light system 7 is positioned on the vehicle 1 in such a way that the light rays are emitted towards the ground 5 with an angle of incidence α which is not zero and they meet it with a greater or lesser inclination depending on whether they are far or close to the vehicle 1. This inclination of the light rays with respect to the ground 5 is defined by the angle of incidence α, which represents the angle formed between the light rays and a normal N to the surface associated 3 with the vehicle 1, as illustrated in the figure, and which can take a value of X° for the images projected closest to the vehicle 1 and a value of Y° for the images projected furthest from the vehicle 1.

[0077] Due to the inclination of the light system 7, and therefore the angle of incidence α with the ground 5 which is variable from one ray to another due to their diffusion at the output, we see an optical phenomenon which causes a deformation of the projected image, a phenomenon known as the "grazing phenomenon".

[0078] This phenomenon of grazing means that the higher the angle of incidence α, the more the projected image is distorted. Thus, a projected image having a square shape at the output of the light system 1 becomes increasingly rectangular as the angle of incidence α increases, stretching in a direction parallel to the orthogonal projection of the optical axis A onto the surface associated 3 with the vehicle 1, here the ground 5.

[0079] The angle of incidence α depends in particular on the distance between the projection area and the light system 7, as well as on the inclination of the latter and in particular on the inclination of the optical axis A of the light system 7, that is to say the inclination of the average light ray exiting the light system 7.

[0080] To illustrate this, the diagram schematically shows the projected light beam FP with a first image 15 formed by light rays from the projected light beam FP and a second image 17 formed by light rays from the projected light beam FP. The first image 15 is projected onto the ground 5 at a point closer to the light system 7 than the point on the ground 5 where the second image 17 is projected. Consequently, the angle of incidence α is approximately 45° for the light rays constituting the first image 15, while it is closer to 60° for the light rays constituting the second image 17.

[0081] The second image 17 thus undergoes a greater distortion than the first image. More specifically, in the illustrated plane, namely a vertical plane including the optical axis A of the light system 7, the extent of the first image on the ground 5 has a first size T1 which is smaller than a second size T2 of the second image, the first size T1 of the first spot being closer to a dimensioning of the image of the projected light beam FP at the output of the light system 7.

[0082] In this context, the lighting system 7 according to the invention is configured to project a projected light beam FP whose shape at the output of the lighting system 7 is designed to anticipate and counteract the glare phenomenon. More precisely, the lighting system 7 is configured to generate a projected light beam FP whose dimensions are reduced in the direction where the glare phenomenon distorts the image, that is to say, here, the direction parallel to the orthogonal projection of the optical axis A onto the surface associated 3 with the vehicle 1, here the ground 5.

[0083] In other words, the projected light beam FP is emitted in such a way as to present a rectangular shape at the output of the light system 7. Thus, due to the inclination of the projection onto the ground 5, the grazing phenomenon is exploited to stretch the shorter side of the rectangular image, making it possible to obtain an image on the associated surface 3 that takes on, at least locally, an optimal square shape.

[0084] We then configure the light system 7 as it will be described in the rest of the description so that the projected light beam FP has at its exit, in particular at the level of a diffusion element 11, a dimension in a first direction D1, perpendicular to the optical axis A of the light system 7 and secant to the surface associated 3 with the vehicle 1, which is smaller than its dimension in a second direction D2, also perpendicular to the optical axis A of the light system 7 but parallel to the surface associated 3 with the vehicle 1.

[0085] This is a schematic diagram of the lighting system 7 as defined in the invention. This lighting system 7 comprises various elements enabling the generation of a projected light beam FP of a rectangular shape as previously mentioned.

[0086] The lighting system 7 thus comprises light emission means 19, each configured to produce a collimated light beam FCB, FCV, FCR. In the illustrated example, the lighting system 7 comprises three light emission means 19: a blue light emission means 191, a green light emission means 192, and a red light emission means 193. Each of these means is designed to emit a collimated light beam FCB, FCV, FCR of the corresponding color.

[0087] In other words, the blue light-emitting means 191 is configured to emit a collimated blue light beam FCB, the green light-emitting means 192 emits a collimated green light beam FCV, and the red light-emitting means 193 is designed to emit a collimated red light beam FCR.

[0088] For this purpose, each light-emitting means 19 comprises a light source 21 specific to its color. Thus, the blue light-emitting means 191 comprises a blue light source 211, the green light-emitting means 192 comprises a green light source 212, and the red light-emitting means 193 comprises a red light source 213.

[0089] By way of non-limiting examples, these light sources 21 may be laser sources corresponding to the colours mentioned such as a blue laser source for the blue light emission means 191, a green laser source for the green light emission means 192 and a red laser source for the red light emission means 193.

[0090] In this embodiment, each light-emitting means 19 also includes a first collimating lens 23 and a second collimating lens 25. The blue light-emitting means 191 thus includes a first blue collimating lens 231 and a second blue collimating lens 251. Similarly, the green light-emitting means 192 includes a first green collimating lens 232 and a second green collimating lens 252, and the red light-emitting means 193 includes a first red collimating lens 233 and a second red collimating lens 253.

[0091] These collimating lenses are all configured to collimate FLB, FLV, FLR light beams produced by light sources 21, in order to form collimated FCB, FCV, FCR light beams emitted by light-emitting means 19.

[0092] The operation of the light sources 21 and these collimation lenses to produce the rectangular projected light beam FP will be detailed in particular in the description relating to 5.

[0093] Each of these collimated light beams FCB, FCV, FCR is then directed, either directly by the light emission means 19, or via reflectors, towards a mixing means 27 of the beams of the light system 7. This mixing means 27 allows the collimated light beams FCB, FCV, FCR to be combined into a global light beam.

[0094] The mixing method 27 here consists of a plurality of dichroic mirrors. It should be noted that other mixing technologies besides dichroic mirrors can also be used, provided they are capable of efficiently combining the three collimated light beams FCB, FCV, FCR into a single overall light beam, while directing this overall light beam in a specific direction.

[0095] In this embodiment, the mixing means 27 comprises a blue dichroic mirror 271, a green dichroic mirror 272, and a red dichroic mirror 273. These mirrors are positioned to intercept the light rays emitted respectively by the blue light-emitting means 191, the green light-emitting means 192, and the red light-emitting means 193. Dichroic mirrors have the characteristic of selectively reflecting certain wavelengths while allowing others to pass through. They thus make it possible to select and combine the desired wavelengths, creating an overall light beam resulting from the assembly of the collimated light beams FCB, FCV, and FCR emitted by the three light-emitting means 19.

[0096] In the arrangement shown in the figure, the blue dichroic mirror 271 and the green dichroic mirror 272 must necessarily be dichroic, as they must reflect blue and green light respectively, while allowing other wavelengths to pass through. However, the red dichroic mirror 273 does not need to exhibit this dichroic property, as it only needs to reflect red light and is not penetrated by any other light rays.

[0097] In other embodiments of the invention, the red dichroic mirror 273 can, by way of non-limiting example, be positioned so that blue and green light pass through it. In this case, the red dichroic mirror 273 must be dichroic in order to allow these wavelengths to pass through while reflecting the red light.

[0098] This positioning is particularly relevant in the generation of white light. Indeed, in this context, red light typically constitutes about 50% of the total energy intensity of the overall light beam, making it the limiting component in the production of white light. Positioning the red dichroic mirror 273 so that blue and green light pass through it prevents red light from passing through other dichroic mirrors. This minimizes light intensity losses by eliminating any attenuation due to transmission through the blue dichroic mirror 271 and the green dichroic mirror 272.

[0099] The overall light beam is then directed towards a pivoting mirror device 29. This device 29 can oscillate between a first position and a second position. To do this, it can pivot around one or more axes, allowing it to alternate between the two positions. It should be noted that everything described for a device 29 comprising a single pivoting mirror also applies to a device 29 comprising a plurality of pivoting mirrors.

[0100] The overall light beam is thus reflected by the mirror(s) of the pivoting device 29. It then becomes a reflected light beam FR which is directed by this pivoting mirror and converges towards an entrance face 110 of a diffusion element 11.

[0101] The mirror(s) rotate at an oscillation frequency that generates, from the overall light beam, a displacement of the image of the light beam onto the associated surface. This displacement of the image of the light beam then forms the pictogram to be projected onto the road.

[0102] The diffusion element 11 is designed to diffuse the reflected light beam FR in order to produce the projected light beam FP. The lighting system 7 also includes a projection element 32, configured to project the projected light beam FP, formed by the diffusion element 11, onto the surface 3 associated with the vehicle 1.

[0103] A collimation means 31 is placed between the pivoting mirror device 29 and the mixing means 27. This collimation means 31 allows the overall light beam FG to be collimated before it reaches the pivoting mirror device 29.

[0104] These different optical elements are configured so that on the input face 110 of the diffusion element 11, onto which the beams from the output of the pivoting mirror device 29 are directed, the projected image of the reflected light beam FR takes a rectangular shape, as will be described in relation to the, in order to produce the projected light beam FP by the light system 7 on the surface associated 3 with the vehicle 1 in a desired orientation to counter the previously described grazing phenomenon.

[0105] Figure 1 represents a schematic diagram of the isolated light-emitting modules of the lighting system 7, in a plane perpendicular to the first direction D1, in order to make visible the dimensions in the second direction D2. Figure 2, on the other hand, is a schematic diagram of an isolated light-emitting module, in a plane perpendicular to the second direction D2, in order to make visible the dimensions in the first direction D1.

[0106] In order to produce the projected light beam FP that counteracts the glare phenomenon—that is, a projected light beam FP with a rectangular shape oriented as desired and described above—the light sources 21 also have a rectangular shape, and this shape is specifically oriented. More precisely, each light source 21 has a first dimension S1 corresponding to its size in the first direction D1, and a second dimension S2 corresponding to its size in the second direction D2, the first dimension S1 being smaller than the second dimension S2.

[0107] More precisely, the ratio between the first dimension S1 and the second dimension S2 is between 0.005 and 0.3. For each light source 21, the first dimension S1 is thus between 0.5 and 4 µm, while the second dimension S2 is between 15 and 90 µm.

[0108] These dimensions can vary depending on the color of the light source 21. For example, for the blue light source 211, the first dimension S1 is between 0.85 and 0.95 µm and the second dimension S2 is between 40 and 50 µm. For the green light source 212, the first dimension S1 is between 1.05 and 1.15 µm and the second dimension S2 is between 15 and 25 µm. Finally, for the red light source 213, the first dimension S1 is between 1.1 and 1.2 µm and the second dimension S2 is between 75 and 85 µm.

[0109] It should be noted that the dimensions of the light sources 21 can influence the divergence of the light beams FLB, FLV, FLR emitted by these sources 21. Indeed, in some cases, the smaller the size of the light source 21, the more divergent the light beams FLB, FLV, FLR are. In other words, in some cases, the light rays of the beam diverge more when the size of the light source 21 is reduced compared to a larger light source 21.

[0110] This phenomenon corresponds to a diffraction effect, the impact of which is particularly pronounced when the dimensions of the light sources approach the micron scale. Indeed, for dimensions on the order of tens or hundreds of microns, the diffraction effect has a negligible, or even nonexistent, influence on the divergence of light rays. Conversely, when the dimensions of the sources reach the micron scale, the influence of the diffraction phenomenon on the divergence of light rays becomes significantly more marked.

[0111] In this embodiment, the light beam FLB, FLV, FLR diverges more in the first direction D1 than in the second direction D2 and the first dimension S1 of the light sources 21 is smaller than their second dimension S2.

[0112] The first collimation lenses 23, positioned closest to the light sources 21 and impacted first by the light rays emitted by the light sources 21, are configured to collimate the light beams FLB, FLV, FLR produced by the light sources 21 in the first direction D1, as can be seen in the figure. In other words, the first collimation lenses 23 make the light rays of the light beams FLB, FLV, FLR, which diverge in the first direction D1, parallel.

[0113] Thus, since the light beams FLB, FLV, FLR diverge more in the first direction D1 than in the second direction D2, the collimation of the light rays of the FLB, FLV, FLR beams in the first direction D1 is performed first. This is why the first collimation lenses 23 are positioned closest to the light sources 21.

[0114] The first collimation lenses 23 of each light source 21 are arranged at a distance from these light sources 21. This distance is called the "collimation distance DC".

[0115] It should be noted that the collimation distance DC depends on the divergence of the light rays in the first direction D1, and therefore on the first dimensions of the light sources 21. However, in this embodiment, the first dimensions of the light sources 21 are equal, so the collimation distances of all the light-emitting means 19 are also equal. In other words, the collimation distance DC of the first blue collimation lens 231 is equal to that of the first green collimation lens 232, which is also equal to that of the first red collimation lens 233.

[0116] The second collimation lenses 25, meanwhile, are configured to collimate the light beams FLB, FLV, FLR produced by the light sources 21 in the second direction D2. Thus, as can be seen in the figure, the second collimation lenses 25 make the light rays of the light beams FLB, FLV, FLR, which diverge in the second direction D2, parallel.

[0117] A focusing distance DF separates the second collimating lenses 25 from their light sources 21. These focusing distances differ for each of the second collimating lenses 25. For example, the focusing distance DF for the blue light-emitting medium 191 can be between 3 and 18 mm, that of the green light-emitting medium 192 can be between 3 and 10 mm, and that of the red light-emitting medium 193 can be between 3 and 20 mm.

[0118] It should be noted that, since the second dimensions S2 move away from the micron scale, the diffraction phenomenon is negligible. Indeed, as mentioned previously, the diffraction phenomenon is particularly pronounced when the dimensions are close to the micron scale; thus, as the size increases, this phenomenon becomes negligible. Consequently, although the second dimensions S2 may vary depending on the light source 21, the divergence of the rays emitted by each light source 21 remains essentially the same.

[0119] In particular, although the blue light source 211 has a second dimension S2 larger than that of the green light source 212, and the red light source 213 has a second dimension S2 larger than that of the blue light source 211, the light rays of each of the beams diverge in an approximately similar way.

[0120] In the illustrated example, the second red collimating lens 253 is located further from the red light source 213 than the second blue collimating lens 251 is from the blue light source 211. Similarly, the second blue collimating lens 251 is located further from the blue light source 211 than the second green collimating lens 252 is from the green light source 212. In other words, the focusing distance DF of the red light-emitting medium 193 is greater than that of the blue light-emitting medium 191, which is itself greater than that of the green light-emitting medium 192.

[0121] In other embodiments, light sources 21 having equal second dimensions S2 could be used.

[0122] It should be noted that the dimensions of the light sources 21 in the second direction D2 are larger than those in the first direction D1.

[0123] Furthermore, the positioning of the second collimation lenses 25 relative to the light sources 21 is further away than the positioning of the first collimation lenses 23 relative to the light sources 21. In other words, the focusing distances are greater than the collimation distances and the first collimation lenses 23 are therefore arranged between the second collimation lenses 25 and the light sources 21.

[0124] The positioning of the second collimation lenses 25 can be adapted to obtain a substantially identical collimation angle for the light rays exiting each second collimation lens 25, so that the light rays of each light beam FLB, FLV, FLR are substantially parallel to each other exiting the second collimation lenses 25. Thus, the focusing distances DF of the second collimation lenses 25 can be adjusted differently for each light emission means 19, for example according to the dimensions of the light sources 21.

[0125] This is a schematic representation of the diffusion element 11 isolated from the light system 7 and which notably makes visible the entrance face 110 of this diffusion element 11. This figure illustrates in particular the rectangular shape of the image projected IP by the reflected light beam FR on the diffusion element 11.

[0126] This rectangular shape results in particular from the combination of 21 rectangular light sources and the different collimation lenses and makes it possible to counter the phenomenon of grazing due to its orientation.

[0127] The projected image IP thus exhibits a first dimension L1 in the first direction D1, which is smaller than a second dimension L2 in the second direction D2. More precisely, the ratio between the first L1 and the second dimension L2 is between 0.015 and 0.8. The first dimension L1 is therefore between 1.25 and 67 times smaller than the second dimension L2.

[0128] The first dimensioning L1 can therefore be between 5 and 100 µm, while the second dimensioning L2 can be between 60 and 300 µm.

[0129] Thanks to these dimensions, the projected light beam FP, when subjected to the grazing effect by being projected into the desired area, in this case the high-definition projection area ZH, stretches in the first direction D1, thus reaching a size comparable to that of its dimension in the second direction D2. This makes it possible to take into account the grazing phenomenon, thus avoiding the formation of a rectangular image by distortion and instead obtaining a square image projected into the high-definition projection area ZH.

[0130] As described above, the present invention achieves its intended purpose by providing a vehicle lighting system configured to project information onto a surface associated with the vehicle. This lighting system is designed to emit a light beam of a specific shape to compensate for the glare effect caused by the system's position relative to the surface.

[0131] 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 any technically operative combination of such means.

Claims

Lighting system (7) of a vehicle (1) configured to project information onto a surface associated (3) with said vehicle (1), the lighting system (7) comprising: light emission means (19), each of the light emission means (19) being configured to form a collimated light beam (FCB, FCV, FCR), a pivoting mirror device (29), a diffusion element (11), a beam mixing means (27) configured to combine the collimated light beams (FCB, FCV, FCR) into a global light beam (FG) directed towards said pivoting mirror device (29), the latter being capable of being controlled to reflect the global light beam (FG) into a reflected light beam (FR) directed towards a diffusion element (11), which is configured to diffuse the reflected light beam (FR) into a projected light beam (FP) capable of being projected by a projection element (32) towards the surface associated (3) with the vehicle (1),characterized in that an image (IP) of the reflected light beam (FR) presents on an entrance face of the diffusion element (11): a first dimension (L1) in a first direction (D1) secant to the surface associated (3) with the vehicle (1), a second dimension (L2) in a second direction (D2) parallel to the surface associated (3) with the vehicle (1), said second dimension being significantly larger than the first dimension. Lighting system (7) according to claim 1, wherein a ratio between the first dimensioning (L1) and the second dimensioning (L2) is between 0.015 and 0.

8. Light system (7) according to claim 1 or 2, wherein: the first dimensioning (L1) of the image (IP) of the reflected light beam (FR) projected onto the diffusion element (11) is between 5 and 100 µm, the second dimensioning (L2) of the image (IP) of the reflected light beam (FR) projected onto the diffusion element (11) is between 60 and 300 µm. Light system (7) according to any one of claims 1 to 3, wherein at least one of the light emission means (19) comprises: a light source (21) configured to emit a light beam (FLB, FLV, FLR), a first collimating lens (23) and a second collimating lens (25), configured respectively to collimate the light beam (FLB, FLV, FLR) in the first direction (D1) and to collimate the light beam (FLB, FLV, FLR) in the second direction (D2), in order to form the collimated light beam (FCB, FCV, FCR). Light system (7) according to claim 4, in which the light source (21) has: a first dimension (S1) in the first direction (D1), a second dimension (S2) in the second direction (D2), larger than said first dimension (S1), a ratio between the first dimension (S1) and the second dimension (S2) being between 0.005 and 0.

3. Light system (7) according to claim 5, wherein: the first dimension (S1) of the light source (21) is between 0.5 and 4 µm, the second dimension (S2) of the light source (21) is between 15 and 90 µm. Light system (7) according to any one of claims 4 to 6, wherein the first collimating lens (23) is arranged between the light source (21) and the second collimating lens (25). A lighting system (7) according to any one of claims 4 to 7, comprising a red light emission means (193), a green light emission means (192) and a blue light emission means (191), each comprising: - a light source (21) configured to emit a light beam of the corresponding color (FLB, FLV, FLR), - a first collimating lens (23) configured to collimate the light beam (FLB, FLV, FLR) in the first direction (D1), - a second collimating lens (25) configured to collimate the light beam (FLB, FLV, FLR) in the second direction (D2). Light system (7) according to claim 8, wherein a focusing distance (DF) extends between the second collimating lens (25) and the light source (21) of each of the light emission means (19), the focusing distance (DF) of at least two of the light emission means (19) being different. Light system (7) according to any one of claims 8 or 9, wherein a collimation distance (DC) extends between the first collimation lens (23) and the light source (21) of each of the light-emitting means (19), the collimation distance (DC) of at least two of the light-emitting means (19) being equal. motor vehicle (1) equipped with a lighting system (7) according to any one of claims 1 to 10, said lighting system (7) being configured to project information onto a ground (5) on which the vehicle (1) rests.

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