FR3007501A1 - DEVICE FOR LIGHTING A VEHICLE USING A MULTIFUNCTION OPTICAL LENS - Google Patents

Abstract

The invention relates to an optical lens (1) comprising a first planar input diopter (2) and an output diopter (5). The main technical feature of a lens according to the invention is that it comprises a second non-coplanar planar input diopter (3) with the first input diopter (2), and arranged in said lens (1) so that all the rays coming from a point of this second input diopter (3) reach an intermediate diopter (4) reflecting the lens (1), which is located between the first input diopter (2) and the diopter of output (5), and which returns said rays on said output diopter (5).

Description

FIELD OF THE INVENTION The invention relates to a vehicle lighting device using a multifunction optical lens. Lighting devices intended to be mounted in vehicle projectors, exist and have already been the subject of patents. For example, patent application EP2525142 relates to a lighting device comprising a lens having an input diopter and an output diopter and at least one light source capable of emitting light towards said input diopter. Such a lighting device can produce a light beam for illuminating the road in front of the vehicle and having a rectilinear cut to separate a zone illuminated by said beam and an unlit area, so as not to dazzle the drivers of vehicles tracked or coming in the opposite direction. Such a lighting device has the disadvantage of being able to produce only one type of light beam, such as for example, those emitted by low beam or high beam. However, current vehicles increasingly tend to have at least two types of light beams, one type being dedicated to lighting the road in dark weather or at night, and another type is dedicated to the signaling of the road. day vehicle. Generally, this dual need is regulated by means of at least two separate luminous devices, placed in a vehicle front projector, increasing the manufacturing time and mounting time of said devices in said projector, and increasing the bulk within said projectors. A lighting device according to the invention makes it possible to produce several types of light beams intended to fulfill different functions within a vehicle, while remaining compact in size due to a limited number of parts involved. The invention firstly relates to an optical lens comprising a first plane input diopter and an output diopter.

The main characteristic of a lens according to the invention is that it comprises a second non-coplanar planar entrance diopter with the first input diopter, and arranged in said lens so that all the rays coming from a point of this second input surface reaches an intermediate reflective diopter of the lens, which is located between the first input diopter and the output diopter, and which returns said rays on said output diopter. In this way, in association with light sources capable of illuminating the first and second input diopter, such a lens is configured to produce, by the output diopter, at least a first type of light beam coming directly from the first diopter of the light. input, and at least one second type of light beams from the second input diopter after reflection on the intermediate diopter. Thus, thanks to this single lens, several types of light beams can be emitted, for example, to illuminate the road and to ensure a day signaling of the vehicle. The geometry of this lens remains compact, since the second input diopter and the intermediate diopter are inserted between the first input diopter and the output diopter, without requiring an increase in the dimensions of said lens. The two input dioptres are materialized by two plane surfaces forming an angle between them.

Advantageously, the first input diopter and the second input diopter are included in planes forming between them an angle of between 85 ° and 95 °. This is a configuration easy to manufacture, and for which the trajectories of the light beams emitted by light sources illuminating said two input dioptres are well mastered. Preferably, the first input diopter extends in a plane which is substantially perpendicular to an axis connecting the center of said first diopter to the center of said output diopter, the second input diopter extending in a plane which is substantially parallel to said axis. According to one embodiment of the invention, the exit diopter is a surface 30 having two foci, the lens having an optical axis passing through these two foci. Advantageously, one of these foci is positioned on the first input diopter, so that all the rays starting from this focus towards the output diopter, leave the lens by the exit diopter while being parallel to each other in a plane vertical parallel to or including the optical axis of the lens. Thus the exit diopter surface may be formed by an elliptical vertical generator sweeping a horizontal director, the latter may for example be an ellipse or a parabola. This exit dioptre can be for example constructed in the same way as that of the lenses disclosed in EP2525142. Preferably, the second input diopter and said intermediate diopter are placed on either side of the optical axis of the first input diopter. In other words, the light beams emitted by a light source placed at the focus of the first input diopter and directed towards the exit diopter are located between the second input diopter and the intermediate diopter.

Advantageously, the intermediate diopter and the output diopter are arranged between them so as to create a focus at the second input diopter, so that all the rays starting from this focus and being reflected by the intermediate diopter towards the output dioptre, out of the lens being parallel to each other in a vertical plane parallel to or comprising the optical axis of the lens. Advantageously, the output diopter is of ellipsoidal shape. Advantageously, the major axis of the ellipse partially delimited by the output diopter coincides with the optical axis of the first input diopter. Preferably, the intermediate diopter is reflective by means of depositing a thin layer of aluminum. Indeed, in order to improve the reflective properties of the intermediate diopter, an aluminum deposit can be performed on said intermediate diopter without disturbing the light beams from the first input diopter. The second object of the invention is a lighting device for a vehicle, comprising a lens according to the invention.

The main characteristic of a lighting device according to the invention is that it comprises at least a first light source capable of emitting light towards the first input diopter, and at least one second light source capable of to emit light towards the second input diopter, the light rays of the beams emitted by said first and second light sources are transmitted by the output diopter. It is assumed that a lighting device according to the invention is intended to be mounted in a vehicle headlight. In this way, a lighting device according to the invention implements a single optical lens according to the invention, to provide both a lighting function of the vehicle and a day signaling function of said vehicle. Each of said functions can be indifferently provided by the first or second input diopter. The luminous intensity of each light source is variable and can thus be adapted to the function it is intended to fill. It may for example be under-watted, if it is required to provide the day signaling of the vehicle. Advantageously, the light rays transmitted by the output diopter form part of the road lighting beam or a day signaling beam of said vehicle, depending on whether they come from the first input surface, the second input surface or both of these dioptres. According to one embodiment of the invention, each first light source and each second light source are constituted by a light emitting diode. This is an effective embodiment in terms of light intensity, and space-saving because of the small size of the diodes compared to other types of light sources. It is possible for each light source cooperating with the lens according to the invention in the device according to the invention to be a light-emitting diode. Advantageously, the light sources, for example light-emitting diodes, are in contact with the input diopter which receives their light rays. When the exit diopter is formed by a surface admitting two foci, one of which is placed at the level of the input diopter, as previously described, the light rays emitted by the light sources emerge parallel to each other in a vertical plane parallel to or comprising the light source. optical axis. This exit dioptre can be for example constructed in the same way as that of the lenses disclosed in EP2525142. Preferably, at least one first light source participates in the formation of the daylighting beam of the vehicle, and at least one second light source in combination with the intermediate diopter participates in forming a portion of the light beam of the vehicle. the road. In this way, each input diopter provides a different function, one for the illumination of the road, and the other for a day signaling of the vehicle. Preferably, the first diopter extends in a transverse plane 15 and vertical and the second diopter extends in a horizontal plane. Advantageously, said lighting device comprises two first light sources placed symmetrically with respect to a vertical and longitudinal plane intersecting the first diopter in the middle, said first sources making it possible to provide a vehicle day signaling function. The notions of "transverse", "longitudinal", "vertical" and "horizontal" are to be interpreted in relation to a reference system linked to a vehicle in which a lighting device according to the invention would be mounted. Advantageously, a lighting device according to the invention comprises a first light source placed at a vertical and longitudinal plane 25 intersecting the first diopter in its middle, said first source making it possible to provide a lighting function of the vehicle. In other words, in addition to a vehicle day signaling function, the first input diopter can also participate in the lighting function of the vehicle.

Advantageously, a lighting device according to the invention comprises two second light sources placed symmetrically with respect to a vertical and longitudinal plane intersecting the second diopter in the middle, the beams coming from said second light sources being reflected by the intermediate diopter. before being transmitted by the output diopter to generate a lighting beam of the road. According to one embodiment of the invention, the first light sources are placed on the same first plane printed circuit board. Advantageously, the second light source or sources are not placed on this flat circuit board. According to one embodiment of the invention, the second light sources are placed on the same second flat circuit board. Advantageously, the first light source or sources are not placed on this flat circuit board. Preferably, the first input diopter is placed at the rear of the output diopter, the second input diopter and the intermediate reflecting diopter being positioned between said first input diopter and said output diopter, said diopter intermediate being located above said second input diopter. In the present application, the terms above, below, above, below, below, and above are in reference to the position in which the lens or device according to the invention is intended to function within a vehicle. The third object of the invention is a vehicle headlamp, the main feature of which is that it comprises a lighting device according to the invention. A lighting device according to the invention has the advantage of implementing a single multi-sided optical lens, and whose compact geometry can be exploited in association with suitable light sources, to fulfill a road lighting function. and a vehicle day signaling function. Therefore, such a device is compact, and generates moderate costs by avoiding the establishment of several lenses each dedicated to a particular lighting function within the vehicle. Finally, it has the advantage of being able to produce a great variability of light beams according to the number and location of the associated light sources, to meet different needs and requirements in terms of lighting. The following is a detailed description of a preferred embodiment of an optical lens and a lighting device according to the invention with reference to FIGS. 1 to 9. FIG. perspective view of an optical lens according to the invention, - Figure 2 is a bottom of the lens of Figure 1, showing two second diodes of a lighting device according to the invention, - Figure 3 is a sectional view of the lens of FIG. 1, in a plane XZ passing through a second diode of a lighting device according to the invention and showing the trajectory of the light beams emitted by said second diodes, FIG. 4 is a top of the lens of FIG. 1, showing three first diodes of a lighting device according to the invention; FIG. 5 is a rear view of the optical lens of FIG. diodes and two second diodes of a lighting system according to the inv Figure 6 is a schematic side view of the lens of Figure 1 showing the path of the light beams emitted by the first three diodes of a lighting device according to the invention. FIG. 7 illustrates an isolux diagram of a light beam produced by the two second diodes of a lighting device according to the invention; FIG. 8 illustrates an isolux diagram of a light beam produced by a first central diode; of a lighting device according to the invention, - Figure 9 illustrates an isolux diagram of a light beam produced by two first lateral diodes of a lighting device according to the invention, - Figure 10 is a diagram. illustrating a vehicle headlight according to the invention. The description of an optical lens and a lighting device according to the invention will be made with respect to a frame linked to a vehicle in which said lens and said device are mounted, and for which the X axis materializes. a longitudinal axis of the vehicle, the Y axis a transverse axis of the vehicle and the Z axis a vertical axis. It is important to specify that FIG. 6 is not a sectional view along an XZ plane, since the various diodes involved in a lighting device according to the invention are not all written in the same vertical and longitudinal plane. . This view is essentially to show the trajectory in a plane XZ of the different light beams emitted by the different first and second diodes. Referring to FIG. 1, an optical lens 1 according to the invention comprises a first input diopter 2, a second input diopter 3, an intermediate reflecting diopter 4 and an output diopter 5. Referring to FIG. 1 and 5, the first input diopter 2 is constituted by a plane face inscribed in a transverse and vertical plane YZ, and whose longitudinal axis extends in a transverse direction Y and horizontal. This face 2 is constituted by a central portion 6 of low height and extending horizontally, said central portion 6 being extended at each of its two ends by an enlarged trapezoidal portion 7, projecting in height. The central portion 6 comprises a central protuberance 20 of rounded shape and projecting also in height. This first input diopter 2 constitutes the rearmost part of the optical lens 1. The output diopter 5 is for example a surface of ellipsoidal shape having a double curvature: a first curvature in a horizontal plane XY as shown by the FIGS. 2 and 4, and a second curvature in a vertical and longitudinal plane XZ as shown in FIGS. 3 and 6. More precisely, this exit diopter 5 constitutes an ellipsoid portion, of which a first focus F1 is situated at the level of first diopter input 2 and whose second focus F2 is positioned within this output diopter 5. This output dioptre 5 is the most forward portion of the optical lens 1. Referring to Figures 2 and 4, the center of the output diopter 5 considered along a transverse axis Y and the center of the first input diopter 2 considered along a transverse axis Y, are aligned along a longitudinal axis X. More specifically, the lens 1 presents a plane of vertical and longitudinal symmetry, passing through the points materializing said centers. Referring to FIG. 2, the second input diopter 3 is materialized by a rectangular and horizontal face 8, the long side of which is parallel to a transverse axis Y. The length of a large side of this rectangular face 8 , is equal to the length of the first input diopter 2 considered along a transverse axis Y, and including the central portion 6 and the two trapezoidal portions 7. The first 2 and the second 3 input diopter 2 are perpendicular, the second dioptre 3 constituting the lower part of the lens 1. Referring to FIGS. 1, 3, 4, 5 and 6 the diopter 4 intermediate 30 reflecting is represented by an inclined wall that can be either rigorously flat or with a light relief. This wall 4 is substantially rectangular, the two long sides defining said wall 4 extending along a transverse axis Y, and the short sides being in planes forming an angle of the order of 45 ° with a vertical YZ plane. This intermediate diopter 4 originates at the level of the horizontal upper edge of the central portion 6 of the first input diopter 2 and extends towards the front of the lens 1, towards the exit diopter 5. The second diopter of input 3 and the intermediate diopter 4 are placed on either side of the optical axis of the first input diopter 1, said axis passing through a focus of said first diopter 2. The intermediate diopter 4 and the output diopter 5 are arranged in such a way as to create a focus at the level of the second input diopter 3. In summary, the first input diopter 2 constitutes the rearmost part of the lens 1 and the output dioptre 5 its most important part. forward, the intermediate diopter 4 and the second input diopter 3 being positioned between said first diopter 2 and said output diopter 5. Preferably, the intermediate diopter 4 is placed above the second input diopter 3. The different diopters 2,3,4,5 are interconnected by means of transparent surfaces having no influence on the optical properties of the lens 1. The reflective properties of the intermediate diopter 4 can be improved by means of a deposition of aluminum . A lighting device according to the invention comprises an optical lens 1 according to the invention, three first electroluminescent diodes 9, 10, 11 capable of emitting light towards the first input diopter 2, as well as two second diodes 12 , 13 electroluminescent capable of emitting light towards the second dioptre 3 input. For the rest of the description, a light-emitting diode will be called LED (Light Emitting Diode).

Referring to FIG. 2, the two second LEDs 12, 13 are arranged on the second input diopter 3, symmetrically with respect to a vertical and longitudinal plane XZ intersecting said second diopter 3 at its center.

Referring to FIG. 3, the light beams emitted 14 by said diodes 12, 13 through the second input diopter 3, first reach the intermediate diopter 4, before being reflected towards the exit diopter 5, then to be transmitted by said output diopter 5 in parallel light beams. The two second LEDs 12, 13 are placed at the centers of the second input diopter 3 defined by the intermediate diopter 4 and the output diopter 5. Referring to FIG. 7, the parallel beams transmitted by the output diopter 5 and which are emitted by the two second LED 12,13 placed at the homes of the second input diopter 3, are directed downwards, under a horizontal cut, to provide a lighting function of the vehicle. Referring to Figures 2, 4, 5 and 6, a lighting device according to the invention comprises three first LED 9,10,11 able to emit light to the first diopter 2 input. One of these three LEDs is located centrally on said first input diopter 2, at the central protuberance 20 of the central portion 6 of said diopter 2. Referring to FIG. 6, this first LED 9 is placed at a focus of the first input diopter 2, so that the beams 15 that it emits and which pass through the first input diopter 2 are directly sent to the output diopter 5, which transmits them in beams of parallel light rays 25 in a vertical plane. Referring to FIG. 8, the parallel light beams coming from the first central LED 9 and which are transmitted by the output diopter 5 are directed downwards, under a horizontal cut, in order to provide a lighting function of the vehicle.

Referring to FIGS. 2, 4, 5, and 6, the two other first LEDs 10, 11 are arranged on the first input diopter 2, at the two trapezoidal end portions 7. Thus, these first two LEDs 10,11 are arranged laterally on the first input diopter 2, and symmetrically with respect to the central LED 9, the height of said lateral LEDs 10,11 being lower than that of the central LED 9. Referring to FIG. 6, the light beams 16 emitted by the first two LEDs 10, 11 in lateral position and which pass through the first input diopter 2, are sent directly to the output diopter 10 which makes them visible. transmits towards the front of the lens 1. Referring to FIG. 9, the light beams 16 coming from the first two lateral LEDs 10, 11 and which are transmitted by the output diopter 5 are directed both upwards and downwards, on either side of a horizontal cut, to provide a vehicle day signaling function. The overall light beam produced by a lighting device according to the invention could be illustrated by a final diagram which would result from the superimposition of the three diagrams of FIGS. 7, 8 and 9. In this way, a lighting device according to the invention invention, thanks to three first LED 9,10,11 able to send light to the first input diopter 2 and two LEDs 12,13 able to send light to the second diopter of input 3, can provide a lighting function and a vehicle day signaling function using a single optical lens 1.

In FIG. 10, a projector P according to the invention is schematically illustrated, with a housing B closed by a wall G, allowing the beam emitted by the device 1 according to the invention to pass. This wall G is in particular a transparent ice. This scheme is generally applicable to the projector according to the invention.

Claims (17)

REVENDICATIONS1. Optical lens (1) comprising a first planar input diopter (2) and an output diopter (5), characterized in that it comprises a second non-coplanar planar input diopter (3) with the first diopter of input (2), and arranged in said lens (1) so that all the rays coming from a point of this second input surface (3) reach an intermediate diopter (4) reflecting the lens (1), which is located between the first input dioptre (2) and the output dioptre (5), and which returns said rays on said output dioptre (5). 2. Optical lens according to claim 1, characterized in that the first input surface (2) and the second input surface (3) are included in planes forming between them an angle of between 85 ° and 950. 3. Optical lens according to any one of claims 1 or 2, characterized in that the output dioptre (5) is a surface having two foci F1 and F2, the lens (1) having an optical axis passing through these two foci Flounder F2. 4. Optical lens according to claim 3, characterized in that the second input diopter (3) and said intermediate diopter (4) are placed on either side of the optical axis of the first input diopter (2). ). 5. Optical lens according to any one of claims 1 to 4, characterized in that the intermediate diopter (4) and the exit diopter (5) are arranged between them so as to create a focus at the second diopter of input (3), so that all the rays starting from this focus and being reflected by the intermediate diopter (4) towards the exit diopter (5), emerge from the lens (1) while being parallel to each other in a vertical plane parallel to or including the optical axis of the lens (1). 6. Optical lens according to any one of claims 1 to 5, characterized in that the output diopter (5) is ellipsoidal in shape. 7. Optical lens according to any one of claims 1 to 6, characterized in that the intermediate diopter (4) is reflecting by means of the deposition of a thin layer of aluminum. 8. Lighting device for a vehicle, comprising a lens according to any one of claims 1 to 7, characterized in that it comprises at least a first light source (9, 10, 11) capable of emitting light. light to the first input diopter (2), and at least one second light source (12,13) capable of emitting light towards the second input diopter (3), and in that the light rays of the beams emitted by said first (9,10,11) and second (12,13) light sources are transmitted by the output diopter (5). 9. Lighting device according to claim 8, characterized in that the light rays transmitted by the output diopter (5) form a road lighting beam portion or a day signaling beam of said vehicle, according to they come from the first input diopter (2), the second input diopter (3) or both of these diopters (2,3). 10.Dispositif lighting according to claim 8 or 9, characterized in that each first light source (9,10,11) and each second light source (12,13) are constituted by a light emitting diode. Illumination device according to one of Claims 8 to 10, characterized in that at least one first light source (9) contributes to the formation of the vehicle day signaling beam, and in that at least one second light source (12, 13) in combination with the intermediate diopter (4) participates in forming a lighting beam portion of the road. 12.Dispositif lighting according to claim 11, characterized in that the first diopter (2) extends in a transverse plane and vertical and the second diopter (3) extends in a horizontal plane. 13.Dispositif lighting according to claim 12, characterized in that it comprises two first light sources (10,11) placed symmetrically with respect to a vertical and longitudinal plane intersecting the first dioptre (2) in the middle, and in that said first sources (10, 11) make it possible to provide a vehicle day signaling function. 14.Dispositif lighting according to any one of claims 11 to 13, characterized in that it comprises a first light source (9) placed at a vertical and longitudinal plane intersecting the first dioptre (2) in its middle, and in that said first source (9) provides a lighting function of the vehicle. 15.The lighting device according to any one of claims 11 to 14, characterized in that it comprises two second light sources (12,13) placed symmetrically with respect to a vertical and longitudinal plane intersecting the second diopter ( 3) in the middle, and in that the beams from said second light sources (12, 13) are reflected by the intermediate diopter (4) before being transmitted by the output diopter (5) to generate a beam of road lighting. 16. Lighting device according to any one of claims 9 to 15, characterized in that the first input surface (2) is placed at the rear of the exit diopter (5), and in that the second input diopter (3) and the reflecting intermediate diopter (4) are positioned between said first input diopter (2) and said output diopter (5), said intermediate diopter (4) being located above said second diopter input (3). 17. Front vehicle projector, characterized in that it comprises a lighting device according to any one of claims 8 to 16.