Automotive Lighting System

Abstract

Vehicle Lighting System The invention relates to a lighting system (7) of a vehicle (1) configured to project information onto a surface (3) associated with said vehicle (1), the lighting system (7) being characterized in that an image (IP) of a reflected light beam (FR) projected onto a diffusion element (11) has: a first dimension (L1) in a first direction (D1) intersecting 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), said second dimension being significantly larger than the first dimension. (Figure 6)

Description

Title of the invention: Lighting system for motor vehicles

[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 lighting, project light onto various vehicle-related surfaces to form, for example, pictograms. On the exterior, they can be used for aesthetic functions, 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, but also to improve safety by projecting informative pictograms, such as alerts for risky driving situations, into the driver's field of vision.

[0003] These lighting systems are generally fixed to the vehicle and can be inclined relative to the associated surface, particularly when projecting light onto the ground. For example, in this case, the lighting system is installed in a vertical position above the ground, so that the light beam is projected at an angle to the ground and to the vertical. This inclination is necessary to direct the light beam towards a desired projection area, while integrating the lighting system into the vehicle body, 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 associated surface. This phenomenon, called grazing effect, transforms a square image emitted from the light system into a rectangular image on the ground, thus distorting the pictogram. This results in a projected pictogram of poor quality, 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 lighting system for a vehicle configured to project information onto a surface associated with said vehicle, the lighting system includes: - means for emitting light, each of the means for emitting light being configured to form a collimated light beam, - a device with a pivoting mirror, - a diffusion element, - a beam mixing means configured to combine collimated light beams into an overall light beam directed towards said pivoting mirror device, the latter being capable of being steered to reflect the overall light beam into a reflected light beam directed towards an input 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 is present on the entrance face of the diffusion element: - an initial dimensioning in a first direction intersecting 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 understand that the difference between the value of the first dimensioning and the value of the second dimensioning is at least 25% of the value of the first dimensioning. In this respect, we aim to distinguish this from systems in which a beam image on the entrance face of the diffusion element has a shape with different dimensions due to manufacturing and assembly tolerances, among other things.

[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 means allows collimated light beams to be combined to form an overall light beam. To this end, it may include various devices, in particular dichroic mirrors, configured to allow certain wavelengths to pass through while reflecting others.

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

[0012] The pivoting mirror device may, for its part, comprise one or more pivoting mirrors. Each of these mirrors is designed to oscillate so as to reflect the overall light beam, thus generating a reflected light beam which is made to converge 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.

[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, that is, the spot corresponding to an angular position of the pivoting mirror device, which it projects onto a surface or element. In order 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 on the associated surface. This movement, combined with the effect of retinal persistence, thus makes it possible to form the pictogram on the associated surface.

[0016] When the lighting system is inclined to the ground and to the vertical, as in the present 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 above 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, the glancing phenomenon 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 entrance face of the diffusion element is sized to be rectangular, with the shorter side of the rectangle corresponding to a first dimensioning, in the first direction, and the longer side of the rectangle corresponding to a second dimensioning, 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, which makes it possible to obtain 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 initial dimensioning of the image of the reflected light beam projected onto the diffusion element is between 5 and 100 pm, - the second dimensioning of the image of the reflected light beam projected onto the diffusion element is between 60 and 300 pm.

[0023] These image size values ​​for the light beam projected onto the entrance face of the diffusion element are particularly well-suited to an application aimed at projecting a pictogram onto the ground on which the vehicle is resting. These values ​​make it possible, in particular, to obtain optimal pictogram quality in a high-definition projection area, which can be located at a distance of between 0.3 and 1.5 m from the vehicle, for a lighting system mounted on the vehicle at a height of between 0.1 and 0.5 m.

[0024] By way of 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 pm and the second dimensioning 120 pm.

[0025] According to an optional feature of the invention, at least one of the light emission means comprises: - a light source configured to emit a beam of light, - 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 direction and in the second direction by the first collimating lens and the second collimating lens, which makes it possible to give it the desired shape, thus allowing the image projected onto the diffusion element to have the desired rectangular shape.

[0027] In other words, the collimating lenses adjust the opening angles of the light beam in order to obtain 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 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 obtain a rectangular image projected onto the entrance face of the diffusion element. This configuration makes it possible to anticipate the grazing phenomenon, by using the shape of the projected image to compensate for the distortions associated with said grazing phenomenon.

[0034] It should also be noted that the dimensions of the light source can influence the divergence of the light rays emitted by the light beam. Indeed, in some cases, the smaller the dimensions of the light source, the more divergent the light rays of the light 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 pm,

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

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

[0040] It should be noted that these dimensions are intrinsically linked to the specific characteristics of the laser source, in particular 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 due to the fact that the light rays are more divergent in the first direction, and that, consequently, in order to recover a maximum of these light rays and collimate them effectively, it is necessary to position the first collimating lens 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 color corresponding,

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

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

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

[0049] Each means of light emission thus comprises 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 means. Indeed, the larger the second dimension of the light source, the larger the light beam generated by the light source is in the second direction. Thus, depending on the desired shape of the projected image, the collimating lens is positioned at an appropriate focusing distance in order to collect more or fewer light rays, thereby controlling the size of the light beam in said 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 emission means, the collimation distance of at least two of the light emission means being equal.

[0053] The collimation distance is substantially identical for each light-emitting means, since the first dimension of the light sources of each light-emitting means is relatively close. Consequently, the divergence in the first direction is substantially identical, which means that the first collimation lenses are arranged at the same distance in order to efficiently collect the diverging light rays in this 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 makes it possible to compensate for the glancing 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 accompanying drawings on the other hand, in which:

[0057] [Fig.1] is a top view of a motor vehicle equipped with a lighting system according to the invention;

[0058] [Fig.2] is a schematic representation of the lighting system illuminating a surface associated with the motor vehicle;

[0059] [Fig.3] is a schematic diagram of the lighting system as defined in the invention;

[0060] [Fig.4] represents a schematic diagram of the light emission modules isolated from the light system, in a plane perpendicular to a first direction;

[0061] [Fig.5] is a schematic diagram of an isolated light emission module, in a plane perpendicular to a second direction;

[0062] [Fig.6] is a schematic representation of a diffusion element isolated from the lighting system, making visible in particular the entrance face of this diffusion element.

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

[0065] Fig. 1 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 3 with the 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 the vehicle 1 rests, and more particularly, to project the light pictogram onto a general projection area ZG represented by dotted lines on [Fig.1] and which is located along the 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, and it includes, near the vehicle 1, a high-definition projection zone ZH, which corresponds to an area where the aim is to obtain the sharpest possible pictogram. The quality of the illuminated pictogram projected by the lighting system must therefore 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 in [Fig. 2].

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

[0072] Fig. 2 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 [Fig.2] (reference 13), the images of the light source which are thus projected are without distortion, the angle of incidence a being substantially zero.

[0076] However, here, the light system 7 is positioned on the vehicle 1 such 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 [Fig.2], 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, an optical phenomenon occurs which causes a distortion of the projected image, a phenomenon known as the "grazing phenomenon".

[0078] This phenomenon of glancing means that the higher the angle of incidence α, the more the projected image is distorted. Thus, a projected image having at the output of the system luminous 1 a square shape becomes increasingly rectangular as the angle of incidence a 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 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, [Fig. 2] 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 location closer to the light system 7 than the location 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 particularly, 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 Tl which is less than a second size T2 of the second image, the first size Tl 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 glancing 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 glancing 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 which takes on at least locally an optimal square shape.

[0084] The lighting system 7 is then configured as described below so that the projected light beam FP has, at its output, particularly at a diffusion element 11, a dimension in a first direction Dl, perpendicular to the optical axis A of the lighting system 7 and secant to the surface associated 3 with the vehicle 1, which is smaller than its dimensioning 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] The [Fig.3] is a schematic diagram of the light system 7 in the sense of the invention. This lighting system 7 includes 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-emitting means 19, each configured to produce a collimated light beam FCB, FCV, FCR. In the illustrated example, the lighting system 7 comprises three light-emitting means 19: a blue light-emitting means 191, a green light-emitting means 192, and a red light-emitting 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 light beams FLB, FLV, FLR produced by the light sources 21, in order to form collimated light beams FCB, FCV, FCR emitted by light emission means 19.

[0092] The operation of the light sources 21 and these collimating lenses to produce the rectangular projected light beam FP will be detailed in particular in the description relating to [Fig.4] and 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 an overall light beam.

[0094] The mixing means 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 that 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 [Fig. 3], the blue dichroic mirror 271 and the green dichroic mirror 272 must necessarily be dichroic, since 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, since it only needs to reflect red light and is not traversed by any other light rays.

[0097] In other embodiments of the invention, the red dichroic mirror 273 may, 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 generally 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, which allows 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) pivot with an oscillation frequency that generates, from the overall light beam, a displacement of the image of the light beam on 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 associated 3 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 [Fig.6], 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 4 shows a schematic diagram of the isolated light-emitting modules of the light system 7, in a plane perpendicular to the first direction Dl, in order to make visible in particular the dimensions in the second direction D2. The [Fig.5], for its part, is a schematic diagram of an isolated light emission module, in a plane perpendicular to the second direction D2, in order to make visible in particular the dimensions in the first direction Dl.

[0106] In order to produce the projected light beam FP that counteracts the glancing effect, i.e., 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 particularly, 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 specifically, the ratio between the first dimension SI and the second dimension S2 is between 0.005 and 0.3. For each light source 21, the first dimension SI is thus between 0.5 and 4 pm, while the second dimension S2 is between 15 and 90 pm.

[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 SI is between 0.85 and 0.95 pm and the second dimension S2 is between 40 and 50 pm. For the green light source 212, the first dimension SI is between 1.05 and 1.15 pm and the second dimension S2 is between 15 and 25 pm. Finally, for the red light source 213, the first dimension SI is between 1.1 and 1.2 pm and the second dimension S2 is between 75 and 85 pm.

[0109] It should be noted that the dimensions of the light sources 21 can influence the divergence of the light beam 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 beam FLB, FLV, FLR. 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 phenomenon, 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 non-existent, influence on the divergence of the light rays. On the other hand, when the dimensions of the sources reach the micron scale, the influence of the diffraction phenomenon on the divergence of the light rays becomes significantly more marked.

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

[0112] The first collimating 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 DL, as can be seen in [Fig. 5]. In other words, the first collimating lenses 23 make the light rays of the light beams FLB, FLV, FLR, which diverge in the first direction DL, 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 light beams FLB, FLV, FLR in the first direction D1 is carried out first. This is why the first collimation lenses 23 are arranged 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 Dl, 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 that 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 collimating 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 [Fig.4], the second collimating 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 means 191 can be between 3 and 18 mm, that of the green light-emitting means 192 can be between 3 and 10 mm, and that of the red light-emitting means 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. It follows that, although the second dimensions S2 may vary depending on the light sources 21, the divergence of the rays emitted by each light source 21 remains substantially 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 placed 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 placed 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 means 193 is greater than that of the blue light-emitting means 191, which is itself greater than that of the green light-emitting means 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] Fig. 6 is a schematic representation of the diffusion element 11 isolated from the light system 7 and which notably shows the entrance face 110 of this diffusion element 11. This figure illustrates in particular the rectangular shape of the image projected IP by the light beam reflected FR on the diffusion element 11. It should be noted that, although the term "projected image" is used, it refers here to a luminous spot formed by the light beam reflected on the diffusion element, and not necessarily an image in the conventional sense.

[0126] This rectangular shape results in particular from the combination of the rectangular light sources 21 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 dimensioning L1 in the first direction D1, which is smaller than a second dimensioning L2 in the second direction D2. More precisely, the ratio between the first L1 and the second dimensioning L2 is between 0.015 and 0.8. The first dimensioning L1 is therefore between 1.25 and 67 times smaller than the second dimensioning L2.

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

[0129] Thanks to these dimensions, the projected light beam FP, when it undergoes the grazing effect by being projected into the desired area, in this case into 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 obtaining instead 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 glancing effect related to the position of the lighting system relative to the associated surface.

[0131] The present invention is not limited to the means and configurations described and illustrated herein and extends also to any equivalent means and configuration as well as to any technically operative combination of such means.

Claims

Demands

1. A lighting system (7) of a vehicle (1) configured to project information onto an associated surface (3) of 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.

2. 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.

3. A lighting 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 pm, - 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 pm.

4. A 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).

5. Light system (7) according to claim 4, wherein the light source (21) has: - a first dimension (SI) in the first direction (D1), - a second dimension (S2) in the second direction (D2), larger than said first dimension (SI) a ratio between the first dimension (SI) and the second dimension (S2) being between 0.005 and 0.

3.

6. Light system (7) according to claim 5, wherein: - the first dimension (SI) of the light source (21) is between 0.5 and 4 pm, - the second dimension (S2) of the light source (21) is between 15 and 90 pm.

7. Light system (7) according to any one of claims 4 to 6, wherein the first collimating lens (23) is disposed between the light source (21) and the second collimating lens (25).

8. 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).

9. 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-emitting means (19), the focusing distance (DF) of at least two of the light-emitting means (19) being different.

10. A 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.

11. Motor vehicle (1) equipped with a light system (7) according to any one of claims 1 to 10, said light system (7) being configured to project information onto a ground (5) on which the vehicle (1) rests.

Images