LIGHTING SYSTEM FOR MOTOR VEHICLES

Description

[0001] The present invention relates in particular to a lighting system.

[0002] A preferred application concerns the automotive industry, for vehicle equipment, in particular for the production of devices capable of emitting light beams, also called lighting functions, generally meeting regulations.

[0003] In particular, the invention can allow the production of a dipped beam type alone or in combination with a signaling and / or lighting function, of much lower intensity.

[0004] The known lighting and signaling devices are so far designed to emit, for example: a dipped beam, directed downwards, still sometimes called a low beam and used when there are other vehicles on the road; a main beam without a cut-off, and characterized by maximum illumination in the axis of the vehicle; a lighting beam for foggy weather, characterized by a flat cut-off and a wide illumination width; a signaling beam for city traffic, also called a city lamp.

[0005] Document US 2007 / 103923 A1 describes a lighting device capable of generating a dipped beam and comprising a plurality of modules generating sub-beams in order to adapt the lighting to the conditions in which the vehicle is located.

[0006] The dipped beam is fundamental insofar as its good definition determines both the quality of the lighting and the absence, or reduction, of the inconvenience caused by the luminous flux produced for surrounding vehicles. Currently, dipped beam headlights are essentially defined with this in mind, with, in particular, the use of sometimes complex cut-offs at the top of the beam, so as to precisely limit or avoid illumination above the horizon line, and to best design a light projection zone to be avoided because it is likely to inconvenience the driver of a passing vehicle.

[0007] Document JP 2014 189198 A describes a lighting system for a motor vehicle comprising a device for projecting a dipped beam. This device for projecting the dipped beam is designed such that the dipped beam comprises a dark area. The disclosed lighting system further comprises an additional projection device configured to project a pixelated beam into said dark area.

[0008] There is, however, a need to improve the definition of the dipped beams.

[0009] The invention falls within this framework.

[0010] It relates in particular to a lighting system for a motor vehicle according to claim 1, said system comprising a device for projecting a dipped beam in a projection zone.

[0011] According to the invention, this system is such that the projection device is configured so that the dipped beam includes a zone of lesser illumination located inside the projection zone. Thus, the dipped beam has a light intensity modulated according to the projection location in the overall projection zone. This is advantageous in certain circumstances. One of these concerns cases of heavy precipitation, the zone of lesser illumination having a less reflective effect for the driver. Another situation relates to the concomitant projection of an additional beam. Indeed, the zone of lesser illumination can provide a space suitable for the projection of another beam. This beam can in particular allow signaling, being for example provided with a pattern of the pictogram type.While it would have been common to think of superimposing, above the dipped beam, a beam of higher intensity aimed at signaling, the invention offers a less energy-consuming and more flexible solution. Indeed, the zone of lesser illumination of the dipped beam can be the location of an additional projection of low intensity, in particular less than that of the dipped beam. This characteristic also offers a range of technologies that can be used for the projection of the additional beam. These may be beam projection techniques in the form of pixelated rays. These techniques, which are not always powerful in terms of luminous flux, offer great flexibility in the choice of beam shapes. They can be used here, thanks to the zone of lesser illumination of the invention.

[0012] According to an optional characteristic of the invention, it can be provided that the zone of lesser illumination comprises an upper limit angularly offset relative to an upper limit of the dipped beam by an angle value of at least 5°, preferably at least 6°, relative to the emission point of the dipped beam, in a vertical and longitudinal plane.

[0013] According to the invention, the system comprises a device for projecting an additional beam formed of pixelated rays and configured to illuminate an area covering at least part of the area of ​​lesser illumination. This technology offers high resolution and makes it possible to produce different shapes of additional beam. The area of ​​lesser illumination preferably, but not limited to, an upper edge inclined by at least 5°, preferably 6°, relative to a horizontal plane.

[0014] Thus, the invention allows for additional projection within the space occupied by the dipped beam. As a lower intensity area is present, this additional beam may be less illuminating than the dipped beam as projected outside the lower illumination area.

[0015] According to the invention, the dipped beam projection device comprises at least a plurality of modules each capable of producing a sub-beam participating in the dipped beam, the dipped beam projection device being configured so that the relative position of at least two sub-beams can be modified between at least one position in which the zone of lesser illumination is present and at least one other position in which the zone of lesser illumination is absent.

[0016] This possibility allows the system of the invention to be placed in at least two different operating configurations. The first can represent the traditional dipped beam position, without a zone of lesser illumination. The second corresponds to the presence of a zone of lesser illumination. Thus, the system can evolve between two operating modes.

[0017] Other optional features of the lighting and / or signaling system according to the invention, which can be implemented in a combined manner according to any association between them or alternatively, are indicated below: the additional beam is configured to produce the outline of at least one pictogram; the area of ​​lesser illumination is entirely covered by the additional beam; the device for projecting an additional beam comprises a micro-mirror matrix system; the area of ​​lesser illumination is symmetrical around a vertical plane passing through the optical axis of the device for projecting the dipped beam; the area of ​​lesser illumination covers an angular sector of less than 10° in horizontal section; the plurality of modules comprises at least one module configured to produce a sub-beam mobile in rotation; the plurality of modules comprises at least a first group of at least one module located on a first side of the optical axis of the dipped beam projection device, and a second group of at least one module located on another side of said optical axis;the first group is optionally configured to illuminate only on the first side of the optical axis and the second group is configured to illuminate only on the second side of the optical axis each of the first group and the second group may be configured to produce a beam having a portion of lesser illumination on a lateral edge of the beam located on the side of the optical axis, the portions of lesser illumination participating in forming the zone of lesser illumination. each of the first group and the second group may be configured to produce a beam having a profile, along a vertical plane perpendicular to the optical axis, with a narrowing in height in the direction of the optical axis;the first group and the second group are optionally configured to produce beams symmetrical to each other relative to a vertical plane passing through the optical axis. the relative position of the sub-beams produced respectively by the modules of the first group and by those of the second group can be modifiable; the system comprises a third group of at least one module located along the optical axis. ;

[0018] The invention also relates to a vehicle equipped with at least one system as introduced above. The vehicle may comprise two systems, each at a different side of the front part of the vehicle.

[0019] The system can be integrated into a headlight projector unit.

[0020] Other characteristics, aims and advantages of the present invention will appear on reading the detailed description which follows, and with reference to the appended drawings given as non-limiting examples and in which: there figure 1 schematically shows the location of a projection of a dipped beam and the presence of an area of ​​lesser illumination, in profile view. figure 2 shows this projection in top view; the figure 3 illustrates in a vertical plane the dipped beam, here for the example with cut-off; the figure 4 shows a first embodiment of a dipped beam projection device; the figure 5 is an isolux curve of the result of the projection of the dipped beam; the figure 6 presents an example of an optical module with a micro-mirror matrix; the figure 7 shows a possible shape of the additional beam; the figure 8 represents the association of the dipped beam and the additional beam; the figure 9 is a view of the projection of a pictogram in the additional beam during the projection of the dipped beam; the figure 10a shows a second embodiment of a device for projecting the dipped beam, this device being in a first position; the figure 10b is an isolux curve of two sub-beams of the beam projected in this first position; the figure 11a shows a second position of the projection device in the second embodiment; the figure 11b is an isolux curve of two sub-beams of the beam projected in this second position; the figure 12 illustrates a vertical sectional view of an example projection produced by a system according to another embodiment of the invention; figure 13 is part of the method of realization of the figure 12 and shows the result of a projection, seen from above; the figure 14 is an example of the embodiment of a group of modules which can form part of the desired overall beam, for the embodiment of the figures 12 And 13 notably.

[0021] In the characteristics set out below, the terms relating to verticality, horizontality and transversality, or their equivalents, are understood in relation to the position in which the lighting system is intended to be mounted in a vehicle. The terms "vertical" and "horizontal" are used in the present description to designate directions, following an orientation perpendicular to the plane of the horizon for the term "vertical", and following an orientation parallel to the plane of the horizon for the term "horizontal". They are to be considered in the operating conditions of the device in a vehicle. The use of these words does not mean that slight variations around the vertical and horizontal directions are excluded from the invention. For example, an inclination relative to these directions of the order of + or - 10° is here considered as a minor variation around the two preferred directions.

[0022] The term "bottom" or lower part generally means a part of an element of the invention located, along a vertical plane, below the optical axis. The term "top" or upper part means a part of an element of the invention located, along a vertical plane, above the optical axis. The term "parallel" or the notion of coincident axes or lines is understood here in particular with manufacturing or assembly tolerances, substantially parallel directions or substantially coincident axes fall within this scope.

[0023] In the context of the invention, the term "dipped beam" means a beam used when there are passing and / or followed vehicles and / or other elements (individuals, obstacles, etc.) on the roadway or nearby. This beam has a downward average direction. It may optionally be characterized by an absence of light above a plane inclined at 1% downwards on the side of traffic in the other direction, and another plane inclined at 15 degrees relative to the previous one on the side of traffic in the same direction, these two planes defining a cut-off in accordance with European regulations. This upper downward cut-off is intended to avoid dazzling other users present in the road scene extending in front of the vehicle or on the verges of the road.

[0024] The dipped beam, formerly derived from a simple headlight, has undergone developments, the dipped beam function being able to be coupled with other lighting characteristics. New functions have recently been developed, designated as advanced functions and grouped under the name AFS (abbreviation for "Advanced Frontlighting System"), which notably offer other types of beams. These include the so-called BL function (Bending Light in English for cornering lighting), which can be broken down into a so-called DBL function (Dynamic Bending Light in English for mobile cornering lighting) and a so-called FBL function (Fixed Bending Light in English for fixed cornering lighting).These cornering lighting functions are used when driving on curves, and they are performed by means of projectors which emit a light beam whose horizontal orientation varies when the vehicle moves on a curved trajectory, so as to correctly illuminate the portions of road which are intended to be approached by the vehicle and which are not in the axis of the vehicle, but in the direction which it is about to take, resulting from the angle imparted to the steered wheels of the vehicle by its driver. Another function is called Town Light in English, for city lighting. This function ensures the widening of a dipped beam type beam while slightly reducing its range. The function called Motorway Light in English, for highway lighting, performs the highway function.This function increases the range of a dipped beam by concentrating the luminous flux of the dipped beam at the optical axis of the headlight device in question. This function is also known as Overhead Light. This function modifies a typical dipped beam so that signal gantries located above the road are satisfactorily illuminated by means of the dipped beam. Another variant of dipped beam is the so-called AWL (Adverse Weather Light) function. This function modifies a dipped beam so that the driver of an oncoming vehicle is not dazzled by the reflection of the headlights on the wet road.Furthermore, when the dipped headlights are in operation, the vehicle attitude may undergo more or less significant variations, due for example to its load state, its acceleration or its deceleration, which cause a variation in the inclination of the upper cut-off of the beam, resulting either in dazzling other drivers if the cut-off is raised, or in insufficiently illuminating the road if the cut-off is lowered. It is then known to use a range corrector, with manual or automatic control, to correct the orientation of the dipped headlights. Generally speaking, the dipped beam referred to by the invention comprises the dipped beam in accordance with the regulations and its developments, including those described above. Generally speaking, the dipped beam can be understood to mean any beam descending and / or illuminating the road without significantly exceeding the horizon line.

[0025] In the following description, like reference numerals will be used to describe like concepts across different embodiments of the invention. Unless specifically indicated otherwise, technical features described in detail for a given embodiment may be combined with all or part of the technical features described in the context of other embodiments described by way of example and not limitation.

[0026] There figure 1 schematically illustrates an example of downward projection at the front of a motor vehicle 1. In this example, which schematically illustrates the projection of a dipped beam 3, the latter is projected below a horizontal plane 2 so as to impact the roadway 4 at the front of a motor vehicle 1. Reference may be made to the information given previously regarding dipped beams with regard to the projection characteristics of this beam. Overall, the dipped beam 3 comprises an outer envelope with a lower limit 3a defining a limit of the beam envelope closest to the vehicle and corresponding to the greatest inclination relative to the horizontal plane 2 and an upper limit 3b corresponding to an upper limit of the beam envelope 3, the least inclined relative to the horizontal plane 2.

[0027] As previously indicated, one aspect of the invention is to propose a specific or evolving definition of the dipped beam 3. In this context, the figure 1 also schematizes the presence of a zone 5 of lesser illumination. As schematized, zone 5 is delimited by a lower limit 5a and an upper limit 5b represented in dotted lines and defining, in a longitudinal and vertical plane perpendicular to the horizontal plane 2, the maximum and minimum inclinations respectively of the envelope of zone 5.

[0028] By lesser illumination, it is meant that the average luminous illuminance in the zone of lesser illumination 5 is at least 70%, preferably at least 80%, more preferably at least 90%, preferably at least 97%, most preferably at least 99%, lower than the average luminous illuminance in the rest of the projection zone of the dipped beam 3. In other words, it is sought to have almost no light in this zone of lesser illumination. Average luminous intensity values ​​of less than 400 candelas, preferably less than 100 candelas, advantageously less than 50 candelas, more preferably less than 30 candelas will thus be noted in this zone of lesser illumination while in the rest of the beam, and in particular in the immediate vicinity of this zone, the values ​​will be greater than at least 2000 or even 3000 candelas.

[0029] The position of this zone of lesser illumination 5 can vary inside the dipped beam 3, and as an example which will be repeated below, one could have a lower limit 5a of the zone 5 merged with the lower limit 3a of the dipped beam 3. It is particularly interesting, in particular in the use of this zone of lesser illumination for the projection of an additional beam 12 which one wishes to make visible to the driver, that the zone of lesser illumination is arranged inside the dipped beam at a sufficient distance from the upper limit 3b of the dipped beam 3 to be bordered in its upper part by a zone of strong illumination. In particular, it may be provided that the zone of lesser illumination 5 comprises an upper limit 5b angularly offset relative to the upper limit 3b of the dipped beam 3, by an angle α (visible on the figure 1 ) relative to the emission point of the dipped beam in the longitudinal and vertical plane illustrated in the figure 1 , the angle α having a value of at least 5°.

[0030] There figure 2 is a top view of a motor vehicle 1 and of an area located at the front of this vehicle. In this example, the projection of an additional beam 12 inside the dipped beam 3 is shown in dotted lines, the additional beam 12 being able to be configured so as to cover all or part of the area 5 previously presented.

[0031] An advantage of the invention is to ensure that the additional beam 12 takes advantage of the characteristics of the zone 5 to produce specific lighting or signaling within the dipped beam 3. Advantageously, the formation of the zone 5 is reversible in the sense that the definition of the dipped beam can be modified to eliminate this zone, or even reduce it, move it, enlarge it or modify its shape. Examples of embodiments of this beam modification are given later in the description.

[0032] Zone 5 is less illuminated relative to the rest of the dipped beam 3, that is to say that it is presented in a relatively shaded form within the projection zone of the dipped beam 3. The additional beam 12 can carry out a projection at least at the level of this zone 5 so as, for example, to produce a complementary part of the dipped beam 3 relative to a part projected by a base projector of the dipped beam 3 or even to carry out a projection parallel to the dipped beam, for example to produce a signal as will be described in detail later.

[0033] There figure 3 is another illustration of the insertion, in a dipped beam which may be traditional, of an additional beam 12. In this figure, the horizontal plane 2 is represented in the form of a horizon line on a vertical plane containing a vertical axis 7 passing through the optical axis passing through the point A of the lighting system. Conventionally, the illuminated zone 6 of the dipped beam 3 may typically have an upper edge substantially at the level of the horizontal plane 2 of the horizon line and provided with a first portion corresponding to a high cut-off 6a slightly above the horizon, a second portion called a low cut-off 6c slightly below the horizon line, these two portions being joined by an intermediate portion corresponding to a bend 6b, here in the form of a bent portion, in particular linear, joining the portions 6a and 6c.In the example shown but in a non-limiting manner, the bend 6b passes through the optical axis illustrated by the point A. In its lower part, the illuminated zone 6 of the dipped beam 3 may generally have an envelope substantially in a convex curvilinear portion, for example in an arc of a circle or in a pseudo-elliptical portion. It is understood that this configuration generally makes it possible to illuminate an area at the front of the motor vehicle 1 which is located relatively close to the vehicle and which avoids an upward projection likely to dazzle vehicles crossed or followed by the vehicle equipped with the system of the invention.

[0034] At the same time, the present invention may allow additional functionality such as defining a specific area within the previously described illuminated area 6, for example for the projection of an additional beam 12 shown diagrammatically by the frame-shaped dotted lines in figure 3 only for the sake of explanation. The shape of the envelope of the additional beam 12 is in fact not limited.

[0035] In order to carry out the projection of the dipped beam 3 defining the illuminated zone 6, one possibility is the use of a projection device 8 which may or may not be a single-unit and which comprises one or more optical modules 9, 10, 11 here represented in the same assembly, each nevertheless having an individual optical output element.

[0036] In general, the present invention may use, for all or part of the dipped beam projection device, in particular at the level of the modules 9, 10, 11, a light source for example of the light-emitting diode type also commonly called LED. In particular, this LED may be provided with at least one chip capable of emitting light of an intensity advantageously adjustable according to the lighting and / or signaling function to be performed. Furthermore, the term light source here means a set of at least one elementary source such as an LED capable of producing a flux leading to generating at the output of the device of the invention at least one output flux fulfilling at least one desired function. The source is generally associated with a support, connection means as well as heat dissipation means.Preferably, the source is configured to emit along a mean emission direction which is perpendicular to the plane of the LED chip if this source technique is used. The modules may comprise an output diopter through which the beam is emitted, for example in the form of an external lens surface. Other types of sources are also conceivable in the invention, such as one or more laser sources, in particular for pixelated ray devices such as those with a micro-mirror matrix described later.

[0037] Thus, returning to the definition of the dipped beam 3, a projection device 8 as shown in figure 4 and presenting three modules 9, 10, 11 allows for example the formation of a beam of which an isolux curve is represented in figure 5 . In this figure, corresponding to a projection at a given distance from the vehicle, we note the formation of a first sub-beam 13 located on the right side of the isolux curve and for example in the form of closed oval curves and elongated in parallel lines substantially in a portion of the space located on one side of the vertical axis 7. This first sub-beam 13 can correspond to the result of the projection from the first optical module 9. In a relatively similar or even symmetrical manner, a second sub-beam 14 is projected and is located in the case of the figure 5 on the other side of the vertical axis 7 relative to the first sub-beam 13. This second sub-beam 14 may correspond to the result of the projection from the second optical module 10. It is understood that the combination of the first and second sub-beams makes it possible to construct a more global, substantially enlarged assembly. In order to obtain a more intense illumination zone, particularly advantageously at the level of the optical axis, a third sub-beam 15 may be projected although this example is not limiting. For this purpose, the third sub-beam 15 is here centered around the vertical axis 7 so as to produce a zone of greater intensity substantially towards the middle of the width of the dipped beam 3.

[0038] Advantageously, the projection of the third sub-beam 15 is configured so that the zone of greater intensity is located in the vicinity of the horizon line of the horizontal plane 2 and slightly below it. For example, the zone corresponding to the third sub-beam 15 may correspond to a height of between 20 and 50% of the overall height of the dipped beam 3 along the vertical axis 7. The third sub-beam 15 may be the result of the projection produced by the third optical module 11 shown in figure 4 . It will be noted that in the example of the figure 5 , the isolux curves are constructed in such a way that an inflection is present, in the example substantially around the vertical axis 7 so that a less illuminated zone 5 or even not illuminated is present in the dipped beam 3. In the case shown, zone 5 covers a central lower part of the envelope of the illuminated zone so that, contrary to the representation of the figure 1 , the lower limit 3a of the dipped beam 3 is merged with the lower limit 5a of the less illuminated zone 5. Thus, the present invention does not imply that the zone 5 is completely surrounded by a more illuminated zone. In this case, in the case of the figure 5 , the less illuminated zone 5 corresponds to a central lower part of the envelope of the dipped beam 3, the lower part of the less illuminated zone 5 not being bordered by a more illuminated part of the dipped beam 3.

[0039] According to one possibility, the zone of lesser illumination 5 can be used to limit the visual discomfort of the driver in certain driving situations, particularly in the event of heavy precipitation. Indeed, these situations tend to produce a partial reflection of the dipped beam which is likely to dazzle the driver. The presence of a zone of lesser illumination, as such, makes it possible to limit this dazzling phenomenon.

[0040] The invention makes it possible to exploit the zone of lesser illumination 5 to carry out the projection of the additional beam 12 mentioned above. For this purpose, a projection device 16 of an additional beam 12 formed of pixelated rays is used. This device is designed to form a projection of the additional beam 12 at least in part in the zone of lesser illumination 5. This additional beam 12 can cover the zone 5 entirely or only partially. It is further understood that the present invention can allow the generation of a plurality of zones of lesser illumination 5 and that the explanations given with reference to the projection of an additional beam 12 can be reproduced for the projection of a plurality of additional beams 12 for example each dedicated to a zone of lesser illumination 5.

[0041] Regarding the projection device 16 of an additional beam 12, current techniques make it possible to carry out a projection of a beam, for example collimated or convergent, formed of a plurality of rays which can be individually controlled so as to produce a particularly precise and modifiable beam definition. In this sense, a pixelated and digital imaging system can be used.

[0042] The terms "pixelated and digital imaging system", "pixelated ray imaging system" or their equivalents are defined as a system emitting a light beam, said light beam being formed of a plurality of light sub-beams, each light sub-beam being able to be controlled independently of the other light sub-beams. Each independently controllable sub-beam forms a pixelated ray. These systems may be, for example, micro-mirror matrices, in particular rotationally controllable, or liquid crystal devices. Another technology for forming pixelated rays is provided with a laser source whose beam is returned by a scanning device onto a surface arranged at the focus of a projection optic and composed of a plurality of elements of luminophore material, usually referred to as phosphor.These phosphor elements re-emit white light, which is projected by a lens to form a beam of illumination on the road ahead of the vehicle. The segments of phosphor material are arranged between the laser source and the projection lens, at the focus of this lens.

[0043] There figure 6 illustrates a non-limiting example of a pixelated and digital imaging system 16 called in Anglo-Saxon terms “Digital Micromirror Device” (DMD), that is to say a micro-mirror device, also called a micro-mirror matrix.

[0044] This system comprises a light source 17, which may be, for example, LEDs or laser diodes, or any type of light source. This light source 17 emits a light beam advantageously towards a reflector 18. This reflector 18 is preferably configured to concentrate the incident light flux onto a surface comprising the micro-mirror matrix 19.

[0045] Advantageously, the reflector 18 is configured so that all of the micro-mirrors are illuminated by the light beam reflected by the reflector 18. The reflector 18 may have, along at least one section plane, a pseudo-elliptical or pseudo-parabolic profile.

[0046] Once reflected by at least part of the micro-mirrors, the light beam passes through a diopter 20. Advantageously, this diopter 20 can be a converging lens for example.

[0047] As indicated, after reflection of the light beam on the reflector 18, the latter comes to concentrate on the matrix of micro-mirrors 19. Preferably, the micro-mirrors each have two operating positions, a so-called active position in which they reflect the incident light beam in the direction of the diopter 20, and a so-called passive position in which they reflect the incident light beam in the direction of a light radiation absorbing element not shown in the figure 6 .

[0048] This type of device makes it possible to have a highly resolved pixelated and digitized light beam at the output of the diopter 20: each pixel or pixelated ray making up this beam corresponds to a micro-mirror, and it is then possible to activate or not these micro-pixels by simply controlling the micro-mirrors. This particularity then makes it possible to draw, as needed, the shape of the light beam at the output of the diopter 20 according to the needs of the invention.

[0049] For example, it is possible to activate only part of the micro-mirrors in order to form a cut-off at the level of the light beam exiting the diopter 20. This cut-off allows, among other things, the realization of the functions presented previously.

[0050] There figure 7 illustrates an example of an additional beam 12 produced by a device of the type shown in figure 6 and previously described. The additional beam 12 is rectangular in shape, this shape being advantageously adapted so that the surface area of ​​the additional beam 12 covers the zone of lesser illumination 5 defined inside the dipped beam 3. Typically, the additional beam 12 has a length “L” and a height “H”, the length “L” being able to correspond for example to an angular sector of deflection of the additional beam 12 in a horizontal plane following an amplitude for example between 4 and 25° and in particular 20°. In terms of height “H”, the latter can correspond, in a vertical plane, to an angular sector between 5 and 20° and in particular 12°. As shown, the definition of the additional beam 12 is very fine thanks to the use of the pixelated and digital imaging system.

[0051] There figure 8 presents the result of the association of a projection from the projection device 8 of the dipped beam 3 and the additional beam 12.

[0052] For this purpose, we find as in the case of the figure 5 the first and second sub-beams 13, 14 forming the lateral wings of the dipped beam 3 as well as a zone of higher light intensity substantially at the level of the upper end of the overall beam relatively centered at the level of the optical axis corresponding to the third sub-beam 15. The additional beam 12 appears below the third sub-beam 15 in the form of a rectangular section making it possible to superimpose a light signal in the beam coming from the projection device 8.

[0053] There figure 9 presents a practical illustration of the additional beam 12. The projection device 16 of the additional beam in the form of pixelated rays has been controlled so as to generate a shaded area included in the additional beam 12 and corresponding to the contours of a pictogram 21. Thus, it suffices, in the context of a DMD device, to control certain micro-mirrors in the inactive position so as to create a shaded area inside the additional beam 12 so as to generate graphic information. It is obviously possible to generate several pictograms 21 and to modify the control of the imaging device to alternately project a plurality of different pictograms according to the desired information. The projection of a pictogram can be linked to information received from a system on board the vehicle, for example a navigation system or a control system comprising triggers of safety information.Pictogram 21 can be defined as positive or negative in beam 12.

[0054] One aspect of the invention relates to the possibility of moving from a situation in which a zone of lesser illumination is present to a situation where this zone is absent. According to this aspect, it is also possible to modify the zone of lesser illumination 5 according to the desired applications, in particular the shape of the additional beam 12 to be projected inside the zone of lesser illumination 5. To achieve this object, the device 8 for projecting a dipped beam is configured so as to allow the production of a dipped beam 3 which can evolve at least between two configurations. This device is such that the relative position of at least two sub-beams can be modified. figures 10a à 11b illustrate this ability. In the case of the figure 10a , a projection device 8 is shown comprising a first module 9 located on one side of the optical axis, a second module 10 located on the opposite side of the optical axis and a third module 11, or central module, located between the two previous ones.

[0055] In this configuration, the result of the projection from the first and second modules 9, 10 corresponds to the isolux curves shown schematically in figure 10b . In this figure, the first and second sub-beams 13, 14 coming respectively from the first and second modules 9, 10 have an overlap, preferably around a vertical plane passing through the optical axis. In this configuration, the overall result of the projection is a beam which has little discontinuity in the definition of its envelope.

[0056] There figure 11a shows a different arrangement of the modules 9, 10 of the projection device 8 in which the inclination of the modules 9, 10 has been modified relative to the position of the central module 11. The result of this modification of position is revealed in figure 11b . In this figure, it can be seen that the isolux curves corresponding to the projection of the first sub-beam 13 and to the projection of the second sub-beam 14 respectively from the first and second modules 9, 10 are further apart along a beam width direction. In the example shown, this spacing is such that the first and second sub-beams 13, 14 no longer overlap. Consequently, a zone of lesser illumination can be created in the intermediate space. It should be noted that the curves shown in figures 10b et 11b do not show the third sub-beam 15 from the third module 11 for the sake of simplification.

[0057] However, it is understood that even with the projection of the third sub-beam 15, a zone of lesser illumination 5 would remain present between the first and second sub-beams 13, 14, in a lower portion of the envelope of the dipped beam thus created.

[0058] The invention is not limited to a method of modifying the relative configuration of the sub-beams of the projection device 8 of the dipped beam 3. Thus, the modification can be produced by a movement of a module or a part thereof. For example, the modification of the position of the output diopter of a module, for example by rotation, can be sufficient to carry out the configuration modification. It can be a rotation applied to a projection lens or to an output reflector. The mobility of the module or of a part thereof can in particular be a pivot along one or more axes. According to one possibility, the mobility of the sub-beam considered is oriented along a vertical axis. In the example of figures 10a et 11a , a movement of two modules 9, 10 is also carried out. These movements can be substantially symmetrical, that is to say that, following a vertical pivot, the modules 9, 10 are moved by an equivalent or symmetrical angular sector around a vertical plane containing the optical axis.

[0059] The third module 11 could itself be mobile, for example following a mobility in pivot of horizontal axis to lower or slightly raise the projection of the third sub-beam 15 so as to modify the amplitude and / or the position of the zone of lesser illumination 5.

[0060] It should also be noted that this aspect of the invention makes it possible to modify the shape and the possible overlap of the sub-beams constituting the dipped beam 3. For example, it is possible to increase or decrease the width of the dipped beam 3 or to increase or decrease the overlap of several sub-beams so as to vary and in particular reduce the resulting light intensity at certain locations, which ensures the creation of a zone of lesser illumination 5.

[0061] In another aspect of the invention not shown, more than three modules are present in the projection device 8 of the dipped beam 3. For example, to increase the resulting light power of the sub-beams, several modules are located on one side of the optical axis and several modules are located on the other side of the optical axis. Thus, contrary to what is shown in figures 10a et 11a , module 9 would be replaced by a group of modules comprising at least two modules. A similar situation would arise for module 10. Advantageously, the groups of modules located on either side of the optical axis have mobility along the same pivot axis, the angular sector of this mobility being able to be identical or different.

[0062] As before, module mobility means the mobility of at least part of each module so as to modify the direction of the corresponding sub-beam.

[0063] It may be provided, without departing from the context of the invention, that the projection device is equipped with a first module or group of modules 9 identical to the second module or group of modules 10, or that each of these two modules or group of modules is clearly identified and arranged to form a left module or group of modules and a right module or group of modules. Depending on the light source used (laser source, light-emitting diode, etc.) and the emission power of these sources, and the total luminous flux required by a given projection device, the modules may be equipped with one or more lenses.

[0064] In use, possible applications of the zone of lesser illumination 5 and the projection of an additional beam 12 have been indicated. It will be noted that external parameters can make it possible to control the different configurations of the device and the system of the invention. For example, when detecting precipitation or switching on the windshield wipers, the system of the invention can be positioned so as to modify the configuration of the dipped beam 3. This modification goes in the direction of creating or increasing the surface area of ​​the zone of lesser illumination 5. With regard to the additional beam 12, examples related to navigation or the display of safety information have been previously given for information purposes.

[0065] THE figures 12 à 14 also present another embodiment of the invention. Note that all or part of the characteristics presented in the embodiment of these figures can be combined with all or part of the characteristics presented in the case of the embodiments set out previously. Whereas in the previous embodiments it was preferred to use a right group of modules and a left group of modules having substantially the same characteristics, that is to say final beams substantially identical in shape and size, the embodiment of the figures 12 à 14 allows, in a preferred case, to differentiate the shape of a right beam and the shape of a left beam. More particularly, it is advantageous that the shape of these two beams ensures at least in part the generation of the zone of lesser illumination 5.

[0066] We represented at the figure 12 a possible beam profile seen in cross-section along a vertical plane perpendicular to the optical axis A so as to form the crossing beam 3. In this figure, the optical axis A intersects the illustration plane at an intersection with a vertical axis 7 and a horizontal line 2. A first beam 26, located towards the left, is illustrated and is generally positioned in a quadrant delimited by the horizontal line 2 in the upper part and the vertical axis 7 on the right edge. A second beam 27, located towards the right, is also illustrated and is generally positioned in a quadrant delimited by the horizontal line 2 in the upper part and the vertical axis 7 on the left edge.

[0067] The left beam 26 and the right beam 27 are preferably, but not limited to, symmetrical to each other relative to a vertical plane containing the optical axis A and the vertical line 7. This plane advantageously corresponds to a middle plane of the vehicle. But the beams 26, 27 are each preferably not symmetrical in themselves to preserve a portion of lesser illumination towards the center of the final dipped beam.

[0068] Furthermore, at least one, but preferably both beams 26, 27 preserve a portion of lesser illumination in an area located in the vicinity of the optical axis A, this portion of lesser illumination participating in the zone of lesser illumination 5. In the embodiment illustrated in figure 12 , the beams 26, 27 each produce an illumination bordered in the upper part by the horizontal line 2, corresponding to the horizon line. This illumination starts from a lateral edge, towards the outside of the vehicle, to a central edge which is preferably located at the level of the optical axis A. A majority portion of the illumination produced may have a convex profile directed downwards so as to produce a curved shape such as in the illustration of the figure 12 . Preferably, this convexity does not continue to the lateral edge 28 in the vicinity of the optical axis A, so as to leave a hole in the illumination produced. Thus, preferably, a portion of the lateral edge 28 comprises at this level a narrowing, for example formed by a concave curvilinear line, or even an inclined portion, so as to release a portion of lesser illumination when the beam 26 or 27 approaches the zone located at the level of the vertical 7.

[0069] Preferably, each of these two beams produces an essentially horizontal portion of beam in the vicinity of the optical axis A, for example in the form of a handle as in the case of the illustrations of the figure 12 The illustrated configuration is not limiting and any shape of beam 26, 27 making it possible to clear an unilluminated or less illuminated space at the lateral edge 28 of these beams near the vertical line 7 may be suitable.

[0070] It is possible for the beams 26, 27 to overlap at the level of the vertical plane passing through the optical axis A. Thus, in the context of the invention, the beam 26 is called the left beam in the sense that it is mainly located on a left side of a plane passing vertically through the optical axis A. This does not exclude the left beam from partially illuminating a right side of said plane. It is the opposite for the beam 27, called the right beam.

[0071] Another representation of a result produced by the projection of the two beams 26, 27 is given in figure 13 in top view. In this configuration, the beams 26, 27 converge slightly towards infinity so as to produce a central illumination; but, it preserves a zone of lesser illumination 5 around the optical axis A near the vehicle 1.

[0072] There figure 14 give an example of a group 20 of modules that can be used to form the left beam 26 described above. It is understood that a group 20 of modules can be formed in a corresponding, and advantageously symmetrical, manner for the right beam 27. The group 20 comprises a fairing 25 making it possible to support and envelop at least one module making it possible to generate the beam 26. In the example illustrated, three modules 21, 22, 23 are present. For example, the module 23 can make it possible to generate the portion of the beam 26 comprising the narrowing in the direction of the vertical plane containing the optical axis. This narrowing can for example be obtained using a suitable lens and / or a cover and / or a shaped reflector making it possible not to project light beams, or to limit such projection, in the area corresponding to the narrowing. Any technique for forming a cut-off can be used in this context.

[0073] Still by way of example, the other modules 21, 22 can be used to provide lighting in the rest of the beam 26.

[0074] To the figure 14 , the modules 21, 22, 23 are each equipped with a light source 24 for example in the form of LEDs.

[0075] The example given to the figure 14 is not limiting and a group of a single module could suffice on each side of the vehicle 1. Furthermore, this embodiment is compatible with mobility of all or part of the modules, so as to change the configuration of the beams 26, 27 according to the desired mode of use. For example, the beams 26, 27 can be brought closer together in the direction of the optical axis A so as to reduce or eliminate the zone of lower illumination 5.

[0076] The invention is not limited to the embodiments described, it is defined in the claims.

Claims

1. A motor-vehicle lighting system (1) including a device (8) for projecting a low beam (3) into a projection zone, the projecting device (8) being configured so that the low beam (3) comprises a zone of lesser illumination (5) located in the interior of the projection zone, the projecting device comprising at least a plurality of modules (9, 10, 11, 21, 22, 23) that are each able to produce a sub-beam (13, 14, 15) that participates in the low beam (3), characterized in that the device (8) for projecting the low beam (3) is configured so that the relative position of at least two sub-beams is modifiable between at least one position in which the zone of lesser illumination (5) is present and at least one other position in which the zone of lesser illumination (5) is absent, in that the system comprises a device (16) for projecting an additional beam (12) formed from pixelized rays and configured to illuminate a zone that at least partially covers the zone of lesser illumination (5), the average luminance being lower at least 70%, preferably at least 80%, more preferably at least 90% and preferably at least 97% than the average luminance in the rest of the projection zone of the low beam (3).

2. The lighting system as claimed in claim 1, wherein the zone of lesser illumination (5) comprises an upper limit (5b) that is angularly offset with respect to an upper limit (3b) of the low beam (3) by an angular value of at least 5° with respect to the point of emission of the low beam.

3. The system according to one of the preceding claims, wherein the additional beam (12) is configured to produce the outline of at least one pictogram (21).

4. The system according to one of the preceding claims, wherein the zone (5) of lesser illumination is entirely covered by the additional beam (12).

5. The system according to one of the preceding claims, wherein the device (16) for projecting an additional beam (12) comprises a micromirror-array system (19).

6. The system according to one of the preceding claims, wherein the zone of lesser illumination (5) is symmetric with respect to a vertical plane passing through the optical axis (A) of the device (8) for projecting the low beam (3).

7. The system according to one of the preceding claims, wherein the zone of lesser illumination (5) covers an angular sector of less than 10° in horizontal cross section.

8. The system according to one of the preceding claims, wherein the plurality of modules (9, 10, 11, 21, 22, 23) comprises at least one first group of at least one module located on a first side of the optical axis (A) of the device (8) for projecting the low beam (3), and a second group of at least one module located on another side of said optical axis (A).

9. The system according to the preceding claim, wherein the first group is configured to illuminate only the first side of the optical axis (A) and the second group is configured to illuminate only the second side of the optical axis (A).

10. The system according to the preceding claim, wherein each among the first group and second group is configured to produce a beam (26, 27) comprising a segment of lesser illumination on a lateral beam edge (28) located on the side of the optical axis (A), the segments of lesser illumination participating to form the zone of lesser illumination (5).

11. The system according to the preceding claim, wherein each among the first group and second group is configured to produce a beam (26, 27) having a profile, in a vertical plane perpendicular to the optical axis (A), with a heightwise constriction in the direction of the optical axis (A).

12. The system according to one of claims 9 to 11, wherein the first group and second group are configured to produce beams (26, 27) that are symmetric to one another relative to a vertical plane passing through the optical axis (A).

13. The system according to the preceding claim, wherein the plurality of modules (9, 10, 11) comprises at least one module that is configured to produce a rotatable sub-beam.

14. The system according to the preceding claim in combination with claim 8, wherein the relative position of the sub-beams respectively produced by the modules of the first group and by those of the second group is modifiable.

15. The system according to the preceding claim, comprising a third group of at least one module located along the optical axis (A).

16. A motor-vehicle (1) equipped with a least one system as claimed in one of the preceding claims.