EP2472176B1 - Lighting and/or signalling device, in particular of an automobile - Google Patents

Description

The present invention relates to a lighting and/or signaling device, in particular for a motor vehicle.

Although not exclusively, such a lighting and/or signaling device can be in the form of a motor vehicle light projector, with the aim of producing, for example, a code beam. For such an application, it will be understood that in order to avoid dazzling a motorist arriving in front, it is essential that the projection onto the road of the light beam generated by the lighting and/or signaling device does not exceed one predetermined limit.

An already known lighting and/or signaling device is arranged to produce a wide light beam which has a cutoff (namely the transition between an area illuminated by the beam and an area not illuminated by said beam, these areas being arranged in either side of the cut, this transition occurring over a small area) which is both flat and clear.

• une source lumineuse, par exemple sous la forme d'une ou plusieurs diodes électroluminescentes,
• un élément optique de collection lumineuse (ou collecteur), par exemple de type ellipsoïdal, dont un premier foyer est disposé sensiblement au niveau de la source lumineuse de manière à collecter la lumière issue de ladite source,
• une plieuse présentant une surface réfléchissante et un bord de coupure, de manière à recevoir seulement une partie du faisceau lumineux provenant du collecteur et à produire ainsi un faisceau lumineux élémentaire à coupure, et
• un élément optique de renvoi, par exemple de type parabolique, dont le foyer est confondu avec un second foyer du collecteur de manière à projeter vers l'avant le faisceau lumineux élémentaire à coupure ainsi produit.

When it comes to producing a beam with code cutoff (that is to say whose cutoff includes two branches making a non-zero angle between them, for example an angle between 10° and 60°, in particular between 15° and 45°, preferably an angle substantially equal to 15°) wide, a lighting and/or signaling device conforming to that described in the document can be used US 6,966,675 . This system includes in particular:

• a light source, for example in the form of one or more light-emitting diodes,
• an optical light collection element (or collector), for example of the ellipsoidal type, of which a first focus is arranged substantially at the level of the light source so as to collect the light coming from said source,
• a folder having a reflective surface and a cut-off edge, so as to receive only part of the light beam coming from the collector and thus produce an elementary cut-off light beam, and
• an optical return element, for example of the parabolic type, whose focus coincides with a second focus of the collector so as to project forward the elementary light beam thus produced.

However, this type of device presents a technical limitation in the sense that the cutoff becomes blurred (by blurred cutoff we mean a luminous transition between the illuminated zone and the unlit zone which occurs over an area greater than the extent of a clean cut) on the edges, which is not desirable for use on a motor vehicle.

• un premier faisceau élémentaire à coupure code nette, mais de faible largeur, et
• un second faisceau élémentaire, plus large, à coupure plate et nette.

Also, in order to produce a code-cut beam which is both wide and sharp, it is possible to superimpose two elementary beams, namely:

• a first elementary beam with a clear code cutoff, but of small width, and
• a second elementary beam, wider, with a flat and sharp cutoff.

However, with such a device, the flat cut-off portion of the second elementary beam is found in the first elementary beam and, as this flat cut-off portion is sharp, it is visible even while being embedded in the first elementary beam. This is also not desirable for reasons of homogeneity of the overall beam.

The document US2008/0310180 A1 shows a device according to the state of the art. u

The object of the present invention is therefore to provide a lighting and/or signaling device which produces a cut-off light beam whose forward projection (in particular on a screen perpendicular to the optical axis of said device) presents a sufficiently clear delimitation which does not extend onto the rest of the road, so that motorists arriving in front are not dazzled, while ensuring that the light intensity distribution of the beam thus produced is otherwise homogeneous.

Another object of the present invention is to provide a lighting and/or signaling device whose design and production are both simple and economical.

• un faisceau dont la partie centrale présente, sur un écran perpendiculaire à l'axe optique, une coupure,
• un second faisceau élémentaire présentant, sur un écran perpendiculaire à l'axe optique, une coupure plate comportant une première branche floue et une seconde branche nette, remarquable par le fait que
  • - - la branche floue de la coupure du second faisceau élémentaire est au moins partiellement incluse dans le faisceau ;
• le faisceau présente une coupure comportant au moins une branche nette horizontale, laquelle branche nette se confond sensiblement, sur au moins une partie de sa longueur, avec la branche nette de la coupure du second faisceau élémentaire.

To this end, the invention provides a lighting and/or signaling device, in particular for a motor vehicle, having an optical axis and arranged to produce:

• a beam whose central part presents, on a screen perpendicular to the optical axis, a cutoff,
• a second elementary beam presenting, on a screen perpendicular to the optical axis, a flat cutoff comprising a first fuzzy branch and a second sharp branch, remarkable in that
  • - - the blurred branch of the cutoff of the second elementary beam is at least partially included in the beam;
• the beam has a cutoff comprising at least one net horizontal branch, which net branch merges substantially, over at least part of its length, with the net branch of the cutoff of the second elementary beam.

• un premier faisceau élémentaire présentant, sur un écran perpendiculaire à l'axe optique, une coupure comportant une première branche floue et une seconde branche nette, et
• un second faisceau élémentaire de préférence présentant, sur

un écran perpendiculaire à l'axe optique, une coupure, remarquable par le fait que :

• la branche floue de la coupure du premier faisceau élémentaire est au moins partiellement incluse dans le second faisceau élémentaire ;
• le deuxième faisceau élémentaire présente une coupure comportant une première branche nette et une seconde branche floue, les branches nettes des premier et second faisceaux élémentaires formant entre elles un angle non-nul, la branche floue de la coupure de l'un desdits faisceaux élémentaires étant au moins partiellement incluse dans l'autre des faisceaux.

The invention also provides a lighting and/or signaling device, in particular for a motor vehicle, having an optical axis and arranged to produce:

• a first elementary beam presenting, on a screen perpendicular to the optical axis, a cutoff comprising a first fuzzy branch and a second sharp branch, and
• a second elementary beam preferably presenting, on

a screen perpendicular to the optical axis, a cut, remarkable for the fact that:

• the blurred branch of the cutoff of the first elementary beam is at least partially included in the second elementary beam;
• the second elementary beam has a cutoff comprising a first sharp branch and a second blurred branch, the sharp branches of the first and second elementary beams forming a non-zero angle between them, the blurred branch of the cutoff of one of said elementary beams being at least partially included in the other of the bundles.

Thus, thanks to the invention, a “blur” is generated at the level of the cutoff branch of the first elementary beam, this blur being hidden in the second elementary beam, so that the homogeneity of the overall beam is not affected. disturbed.

A non-limiting example of the distinction between sharp cutoff and fuzzy cutoff is given below.

et β_max est tel que G(β_max) = max(G(β))
On considère qu'une coupure est suffisamment nette dans une zone lorsque G(β_max)≥0.13 pour toutes les valeurs de η de la zone. En dessous de cette valeur la coupure est floue (ou inexistante).If we consider the function E _η (β), illumination provided by a beam on a screen perpendicular to the optical axis of the module producing the beam, screen located 25 meters from this module, where η is an angle defining a lateral direction by relative to the optical axis of the module considered and β an angle defining a vertical direction relative to the optical axis of the module, so that E _η (β) is measured at the point on the screen located at 25.tan(η ) meters to the right of the point of intersection of the optical axis of the module and the screen and 25.tan(β) meters above this point, the sharpness and the position of the beam cutoff in η are defined respectively by G(β _max ) and β _max where $$\mathrm{G}\left(\mathrm{\beta }\right)=\log \left({\mathrm{E}}_{\mathrm{\eta }}\left(\mathrm{\beta }\right)\right)-\log \left({\mathrm{E}}_{\mathrm{\eta }}\left(\mathrm{\beta }+0.1°\right)\right)$$

and β _max is such that G(β _max ) = max(G(β))
We consider that a cut is sufficiently sharp in a zone when G(β _max )≥0.13 for all values of η of the zone. Below this value the cutoff is blurry (or non-existent).

This distinction between sharp cutoff and fuzzy cutoff is for example of a regulatory type, in the sense that this distinction respects an official regulation such as that no. 112 (Appendix 9) on the Adoption of uniform technical prescriptions for wheeled vehicles.

The cutoff of the beam may include two branches making a non-zero angle between them, preferably an angle substantially equal to 15°, said branches being sharp.

• une source lumineuse,
• un élément optique de collection agencé pour collecter la lumière issue de ladite source,
• une plieuse présentant une surface réfléchissante et un bord de coupure en vue de recevoir seulement une partie du faisceau provenant de l'élément optique de collection et de produire ainsi un faisceau lumineux à coupure, et
• un élément optique de renvoi, agencé pour produire vers l'avant ledit faisceau lumineux à coupure.

Preferably, the part of the device according to the invention capable of producing the first elementary beam or the beam comprises:

• a light source,
• an optical collection element arranged to collect the light coming from said source,
• a folder having a reflective surface and a cut-off edge for receiving only part of the beam coming from the optical collection element and thus producing a cut-off light beam, and
• an optical return element, arranged to produce said cut-off light beam towards the front.

In this case, according to a first variant, the optical return elements are made up of non-imaging optical elements.

According to a second variant, the optical return element is made up of an optical imaging element such as a lens.

Preferably, the cutting edge of the folder has, on the side intended to produce the second branch, a main portion, the end of which is in the extension of the side of the cutting edge intended to produce the first branch, and a peripheral portion , the end of which makes an angle with said main portion corresponding to the angle of inclination of said first branch.

In this case, this part of the device capable of producing the first elementary beam is rotated by an angle of rotation of opposite sign and of absolute value substantially equal to the angle of inclination of the second branch.

According to a particular embodiment, the projection on a screen perpendicular to the optical axis of the cut-off of the second elementary beam is more extensive than the projection on this same screen of the cut-off of the first elementary beam.

• la figure 1 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique d'un faisceau lumineux produit par un module de l'art antérieur ;
• la figure 2 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique d'un faisceau lumineux produit par un ensemble de deux modules selon la présente invention ;
• la figure 3 représente schématiquement en vue de dessus une forme de réalisation de la première partie du dispositif d'éclairage selon l'invention ;
• la figure 4 représente schématiquement en vue de coupe la première partie du dispositif d'éclairage de la figure 4 ;
• la figure 5 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique d'un faisceau lumineux produit par la première partie du dispositif d'éclairage des figures 3 et 4 ;
• la figure 6 est un schéma représentant la projection orthogonale d'un faisceau lumineux produit par le module de la figure 4 après rotation ;
• la figure 7 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique d'un faisceau lumineux produit par la seconde partie du dispositif selon l'invention ;
• la figure 8 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique du faisceau lumineux résultant de la superposition des faisceaux élémentaires produits respectivement par les première (figure 6) et seconde (figure 7) parties ;
• la figure 9 est un schéma représentant une seconde forme de réalisation de l'invention, intégrant une lentille ;
• la figure 10 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique d'un faisceau lumineux produit un dispositif d'éclairage selon une autre forme de réalisation de l'invention ; et
• la figure 11 est un schéma représentant la projection sur un écran perpendiculaire à l'axe optique du faisceau lumineux résultant de la superposition des faisceaux produits par les modules des figures 10 et 7.

The figures in the appended drawing will make it clear how the invention can be carried out, in which:

• there figure 1 is a diagram representing the projection on a screen perpendicular to the optical axis of a light beam produced by a module of the prior art;
• there figure 2 is a diagram representing the projection on a screen perpendicular to the optical axis of a light beam produced by a set of two modules according to the present invention;
• there Figure 3 schematically shows a top view of an embodiment of the first part of the lighting device according to the invention;
• there figure 4 schematically represents in section view the first part of the lighting device of the figure 4 ;
• there figure 5 is a diagram representing the projection on a screen perpendicular to the optical axis of a light beam produced by the first part of the lighting device of the figures 3 And 4 ;
• there Figure 6 is a diagram representing the orthogonal projection of a light beam produced by the module of the figure 4 after rotation;
• there Figure 7 is a diagram representing the projection on a screen perpendicular to the optical axis of a light beam produced by the second part of the device according to the invention;
• there figure 8 is a diagram representing the projection on a screen perpendicular to the optical axis of the light beam resulting from the superposition of the elementary beams produced respectively by the first ( Figure 6 ) and second ( Figure 7 ) parts;
• there Figure 9 is a diagram representing a second embodiment of the invention, integrating a lens;
• there Figure 10 is a diagram representing the projection on a screen perpendicular to the optical axis of a light beam produced by a lighting device according to another embodiment of the invention; And
• there Figure 11 is a diagram representing the projection on a screen perpendicular to the optical axis of the light beam resulting from the superposition of the beams produced by the modules of the figures 10 And 7 .

In these figures, identical references designate similar technical elements.

The diagram of the figure 1 corresponds to a code beam produced by a lighting device of the prior art, as described for example in the document US 6,966,675 . This device, which has an optical axis Z-Z', produces a light beam whose projection on a screen (XX';Y-Y') perpendicular to the optical axis ZZ' of the device has a V-shaped cutting edge, this cutting edge comprising a first branch, located at a side of the screen and which is parallel to the horizontal XX', and a second branch, on the other side of the screen and which rises above the horizontal XX' at a non- zero, approximately equal to 15°.

More precisely, the code beam produced by this lighting device of the prior art comprises a central part 1 with more intense lighting limited by a V-shaped cutoff edge 2 whose first branch 2A is substantially horizontal, i.e. i.e. coincident with the axis X-X' of the horizontal plane, and the second branch 2B rises at an angle α relative to the horizontal, that is to say above this axis X-X' of the horizontal plane.

The code beam further comprises a wider part 3, which extends to the right and left of the central part 1. The wide part 3 admits a flat horizontal cutoff 4, located at the same level as the first branch 2A (horizontal) of cutoff 2 in V. The lighting in part 3 is less intense than in part 1, but sufficient to illuminate the side areas.

The V cut 2 of the central part 1 of the light beam produced by this type of lighting device has the disadvantage of being blurred when moving away laterally from the optical axis, due to the presence of geometric aberrations. These blurred areas are shown on the figure 1 , for the two branches 2A and 2B of cutoff 2, respectively in 5A and 5B. Due to this blur, a luminous flux rises beyond the cut-off edge 2 in V, which risks at least partially dazzling motorists arriving in front of the vehicle equipped with this device.

The invention proposes to eliminate these blurred zones at the cutoff edge 2 of the beam produced by the lighting and/or signaling device.

• le bord de coupure en V est net, et
• il n'existe aucune zone lumineuse à intensité discontinue.

For this, the lighting device according to the invention is arranged to produce a first elementary beam which, in superposition with a second elementary beam, has the following characteristics:

• the V-cut edge is sharp, and
• there is no luminous zone with discontinuous intensity.

The orthogonal projection on a vertical plane of such a beam, produced by a lighting and/or signaling device according to the invention, is shown on the figure 2 . This beam includes a V-shaped cutting edge 2, the first branch 2A of which (on the left on the figure 2 ) is substantially horizontal and whose second branch 2B (to the right on the figure 2 ) rises at an angle α close to 15° on the horizontal, these two branches being clear. In addition, the portion 6 located under the second branch 2B is blurred. The value of this angle α is not limiting and can generally be between 10° and 60°.

According to a first variant of the invention, to obtain an elementary light beam whose cutoff has the characteristics mentioned above in projection on a perpendicular to the optical axis Z-Z', a first part of the lighting device and/or or signaling is schematically represented on the figures 3 And 4 .

This first part M comprises a light source S, constituted for example by at least one incandescent lamp, a Xenon lamp or advantageously by at least one light-emitting diode, comprising plane emitters which are located on a single and same plane support in order to facilitate the manufacture of the lighting device and have only one radiator. This source S is arranged so as to illuminate towards the front and upwards. The terms “front” and “rear” are to be understood by considering the normal direction of forward movement of the vehicle equipped with the first part M of the lighting device according to the invention.

A collector mirror R1 is placed in front of the source S and is turned towards the rear. This mirror R1 comprises a first focus F1 at which (or in the vicinity of which) is placed the center of the source S which illuminates towards the mirror R1, as well as a second focus F2 located on the optical axis ZZ' of the first part M of the device.

This first part M also includes a folder P, the upper edge P2 of which constitutes the cutting edge of the beam and passes through (or in the vicinity of) the second focus F2 of the collecting mirror R1.

A deflection mirror R2 is located essentially below the collector mirror R1. The reflecting surface of mirror R2 faces forward to produce the cut-off output beam. The deflection mirror R2 admits a focal point coincident with (or in the vicinity of) the second focal point F2 of the collecting mirror R1. The optical axis of the mirror R2 coincides with the optical axis Z-Z' of the device. The edge of the cutoff P2 of the folder P also passes through the focus of the mirror R2 (or in its vicinity).

A glass (not shown), made of transparent material, can be placed in front of the elements of the first part M of the lighting device.

The surfaces of the collector mirror R1, of the folder P and of the return mirror R2 are conjugate surfaces. This conjugation may consist in particular in that the collection mirror R1 is designed to transform a spherical wave surface coming from the center of the source S into an arbitrary wave surface reducible to a two-dimensional line P1-P2-P3 . In practice, we can choose a toric wave surface for the arbitrary wave surface, and the line P1-P2-P3 is then an arc. This solution allows an analytical calculation and offers a parameter which facilitates the horizontal spreading corresponding to the major radius of the torus. We can choose the convex line P1-P2-P3, seen from outside the projector, which admits a common plane of symmetry with the emitter of the source S. The deflection mirror R2 is determined to transform this wave surface toric into a cylindrical wave surface with a vertical axis admitting any curve for a straight section. This curve, which characterizes the wave emerging from the first part M of the device, is chosen so as to compensate at least in part the horizontal inclination of the plane of the source S relative to the axis ZZ' of the vehicle, and makes it possible to adjust the horizontal spread of the beam. This first part M thus makes it possible to create a wide outgoing beam with a clear cut-off line by using the folder with the line P1-P2-P3 as the cut-off edge, despite the horizontal inclination of the source S.

To obtain a V-cut light beam in accordance with the invention with this type of device, it is desirable, in a non-limiting manner, to use a folder edge of low curvature, at least in the vicinity of the axis, of the side corresponding to the first branch of the cut, and of greater curvature on the other side, so that there is a section of the edge of the folder through which little or no rays pass which are then returned by the exit reflector on the side opposite the optical axis Z-Z'.

Thus, a first side of the folder P1 (on the right on the Figure 3 ) is substantially straight or has a slight curvature, while the second side (on the left on the Figure 3 ) comprises a first portion P2, close to the center and which extends the right side P1, and finally a zone P4 (or cutting edge portion) which forms a determined angle of inclination with the extension P3 (intangible) of the portions P1 and P2, for example 15°.

The width D of the portion P2 is chosen as small as possible such that the rays passing below the cutoff portion P4 are not returned to the opposite side of the axis ZZ' to infinity. To determine the value of this width, it is possible to calculate the normal at any point of the collector reflector by exploiting the following property: a ray coming from the center of the source S and reaching a point of the collector R1 is returned towards the point of the collector folder edge P such that the plane normal to the folder edge at this second point contains the first point.

The normal to the collector R1 at the first point is the bisector of the line connecting the first and the second points and of the line passing through the first point and the center of the source S. In particular, it is possible to calculate the normal at the points from the edge of the collector R1 located in the plane of the source S and to deduce (calculation of the reflected rays for four incident rays coming from each point considered on the collector from the four corners of the source) the horizontal dimensions at the level of the edge of the folder P of the images of the transmitter formed at these points (for each reflected ray, the point of the edge of the folder closest to the straight segment carrying the ray which, in general, does not meet the edge of the folder is determined , and the two extreme points from the point of view of their lateral position on the edge of the folder P are preserved). These dimensions correspond to the “widest” images having a given center.

If we consider that at first order the horizontal power of the deflection mirror R2 is zero (this system simply projects the images to infinity without changing their horizontal angular extent), it is possible to calculate from the rays reflected determined in the manner indicated above, the horizontal angular extent of the images and the position of their horizontal ends (maximum and minimum algebraic horizontal deviation angles) at infinity.

In addition, for each point of the folder P corresponding to the end of an image, it is also possible to calculate the position at infinity of the center of the images whose center at the level of the folder is the point considered (the direction is the zero vertical component vector contained in the plane normal to the edge of the folder at the point considered).

Thus, from the abscissa of the positions on the edge of the folder P of the ends of the widest image whose center passes through the point considered, as well as the extreme horizontal directions after reference to infinity of the widest image whose center passes through the point considered, it is possible to determine the “central” horizontal deviations at the ends (at the level of the folder) of the widest image whose center passes through the point considered .

The abscissa such as the ends at infinity of the largest images and the central directions at the ends of these images at the edge of the folder are on the same side (left or right) of the vertical plane containing the optical axis as the point of the folder. edge of the folder considered are those for which the folder can be cut in order to bring up light without creating glare.

Referring to the Figures 4A and 4B , which respectively represent sectional views of the first part M of the device along the axes ZZ' and B-B', which correspond respectively to portions PA and PB of the folder P, we can see different possible cases for the paths of the light rays.

There Figure 4A represents the first part M of the device in a section at the level of the portion PA of the cutting edge of the folder P, this portion PA being located at the level of the portions P1 and P2.

The ray i1, coming from a point of the source located above its center (and therefore from the first focus F1 of the mirror R1, itself located at the center of the source S), is reflected along a ray which strikes the folder PA above its lower edge, and therefore above the hearth F2. This ray is then reflected along a ray which is itself reflected by the mirror R2 along a descending ray.

The ray i2, emitted from the center of the source S (and therefore from the focus F1), is reflected along a ray which tangents the lower edge of the folder PA without being deviated and is reflected by the mirror R2 along a horizontal ray, which corresponds to the cut-off edge 11B of the beam 10 thus produced, which is along the horizontal.

The ray i3, coming from a point of the source S located below its center (and therefore from the focus F1), is reflected by the mirror R1 along a ray which passes below the lower edge of the folder PA, and therefore below the focus F2. This ray is then reflected by the mirror R2 following a descending ray.

We thus obtain, with this portion PA of the folder P, a portion of the right part of the beam 10 including the cut 11B ( figure 5 ) is horizontal and clean.

There figure 4B represents the first part M of the device in a section at the level of the portion PB of the cutting edge of the folder P, this portion PB being located at the level of the portion P3, itself located in the inclination of the cutting edge of the folder P of an angle α. This PB portion is distinguished in particular from the PA portion (shown in dotted lines on the figure 4B ) by a different length and possibly by a different angle of inclination relative to the mirror R1, for example lower.

Ray i4, coming from the same point as ray i1 of the Figure 4A , is reflected along a ray which, instead of hitting the folder PB above its lower edge as does the ray i1, tangents to said lower edge of the folder PB, without being deviated and is reflected by the mirror R2 along a ascending ray, which corresponds to the cut-off edge 11A of the beam 10 thus produced, which rises above the horizontal.

Rays i5 and i6, respectively emitted from the same points as rays i2 and i3 of the figure 4A (that is to say respectively from the center of the source S and from a point of the source S located below its center), are reflected by the mirror R1 along rays which pass below the lower edge of the PA folder. These rays are then reflected by the mirror R2 along respectively horizontal and descending rays.

We thus obtain, with this portion PB of the folder P, a portion of the left part of the beam 10 including the cut 11A ( figure 5 ) rises by an angle α on the horizontal and is likely to be substantially blurred on a portion 12 covering said cut 11A.

The light beam 10, the projection of which on a plane perpendicular to the optical axis ZZ' is represented on the figure 5 , is thus obtained. This elementary beam 10 has a cutting edge of which a first branch 11A rises at an angle -α relative to the horizontal and a second branch 11B which is substantially horizontal. Furthermore, the area located under branch 11A is blurred when moving away from the optical axis Z-Z'.

• d'un côté (à gauche sur la figure 6), une première branche 21A, sensiblement confondue avec l'axe X-X' du plan horizontal, et
• de l'autre côté (à droite sur la figure 6), une seconde branche 21B, nette, qui fait avec l'axe X-X' du plan horizontal un angle non-nul, et plus particulièrement un angle d'inclinaison α sensiblement égal à 15°.

Subsequently, by rotation of the first part M of the device around the optical axis Z-Z', by an angle of rotation -α corresponding in absolute value to the desired angle of inclination α, but of opposite sign , we obtain the elementary light beam 20 of the Figure 6 , which has a cut 21 whose projection on a screen perpendicular to the optical axis ZZ' comprises:

• on one side (left on the Figure 6 ), a first branch 21A, substantially coincident with the axis XX' of the horizontal plane, and
• on the other side (right on the Figure 6 ), a second branch 21B, sharp, which makes a non-zero angle with the axis XX' of the horizontal plane, and more particularly an angle of inclination α substantially equal to 15°.

On this beam 20, the first branch 21A provides below it a blurred zone 22 located entirely below the horizontal. In addition, the second branch 21B provides below it a zone 23 intended to contain at least partially another elementary light beam (the beam 30 of the Figure 7 described below).

This beam 20 of the Figure 6 , superimposed on a beam 30 with flat cutoff such as that of the Figure 7 , whose cut 31 has two branches parallel to the horizontal axis, a first branch 31A (on the left on the Figure 7 ) being clear and the second branch 31B (on the right on the Figure 7 ) being blurred, makes it possible to obtain the resulting beam 40 of the figure 8 .

The second part of the lighting and/or signaling device according to the invention, which makes it possible to obtain the elementary beam 30 with flat cutoff intended to be superimposed on the elementary beam 20 produced by the first part M of this same device, is a type of module known to those skilled in the art.

More precisely, one way of producing this second part is to use the same system as the first part M which produces the elementary beam 20, but by inverting left and right and by not rotating it by a determined angle around the optical axis Z-Z'.

The resulting beam 40 of the figure 8 , in accordance with the present invention, has a cutoff 41 of which the two branches 41A and 41B are clear, while the beam portions 42 and 43, located respectively under the branches 41A and 41B, are blurred. We thus obtain a beam whose V cut is clear and the light intensity under the cut is homogeneous and without discontinuity, which makes it possible to illuminate as far as possible without exceeding the dazzling limits of motorists arriving in front while ensuring a certain visual comfort. In addition, the two parts of the device (the first part M of the figures 4 And 5 , and the second part which produces the beam of the Figure 7 ) which made it possible to obtain the beam of the figure 8 may not consist of any optical imaging element. This makes it possible in particular to make a sharp cut 31a in the elementary beam 30 extending far to the left, whereas with an imaging system, the sharpness at large lateral angles is limited by the aberrations of the projection/reflection system. In addition, these two parts can be symmetrical to each other, the first part being rotated by a determined angle relative to the optical axis ZZ' of the device and not the second part.

According to another embodiment of the invention, a similar result can be obtained by using an optical projection system such as a non-imaging lens. More precisely, as illustrated in the Figure 9 , it is possible to produce the first part M of the lighting and/or signaling device according to the invention from a concave reflector R1, a light source (not shown) arranged in the concavity of the reflector R1 to illuminate, and a lens L located in front of the reflector R1 and the light source. The reflector R1 is associated with a folder P, the upper face of which is reflective to fold the beam coming from the reflector, and has a front end edge capable of forming the break in the beam produced, this folder P being able to present for example a form similar to the folder described above and shown in figures 3 And 4 . In this first part M, the lens L is also determined to give from a point on the edge of the folder P, for all the rays contained in the plane perpendicular to the front edge of said folder P at the point considered, an image at the 'infinite in this plane.

According to another embodiment of the invention, it is possible to use a device whose first part, with a V-cut, would produce a beam, part of which would go up to the right of the optical axis, without exceeding the V-cut. , and which would not be rotated around its optical axis. In this way it could be possible to increase the value of 75R (photometric value defined at the level of a screen perpendicular to the optical axis of the device and located 25 meters from said device, at a point on this screen located 25 centimeters below and 50 centimeters to the right of the optical axis) without creating a contrast line under the V-shaped tilt zone (at 15°).

Such a V-cut module can for example produce a beam as shown in the Figure 10 , the central part 50 of which has a cutting edge 51 which comprises, on one side (on the right on the Figure 10 ), a branch 51B, clear, which rises by an angle α substantially equal to 15° above the horizontal, and, on the other side (to the left on the Figure 10 ), a branch 51A, also clear and horizontal. This beam 50, superimposed on a beam 30 with flat cutoff such as that of the Figure 7 , makes it possible to obtain the resulting beam 60 of the Figure 11 , which has a cut 61 whose two branches 61A and 61B are clear, while the beam portion 62, located under the branch 61B, is blurred.

Claims (8)

1. Lighting and/or signalling device, notably of a motor vehicle, having an optical axis (Z-Z') and arranged to produce:

   - a beam (50) of which the central part exhibits, on a screen at right angles to the optical axis (Z-Z'), a cut-off (51),

   - a second elementary beam (30) exhibiting, on a screen at right angles to the optical axis (Z-Z'), a flat cut-off (31) comprising a fuzzy first branch (31B) and a sharp second branch (31A),

   characterized in that:

   - the fuzzy branch (31B) of the cut-off (31) of the second elementary beam (30) is at least partially included in the beam (50);

   - the beam (50) exhibits a cut-off (51) comprising at least one horizontal sharp branch (51A), said sharp branch (51A) merging substantially, over at least a part of its length, with the sharp branch (31A) of the cut-off (31) of the second elementary beam (30).
2. Lighting and/or signalling device, notably of a motor vehicle, having an optical axis (Z-Z') and arranged to produce:

   - a first elementary beam (20) exhibiting, on a screen at right angles to the optical axis (Z-Z'), a cut-off (21) comprising a fuzzy first branch (21A) and a sharp second branch (21B), and

   - a second elementary beam (30) preferably exhibiting, on a screen at right angles to the optical axis (Z-Z'), a cut-off (31),

   characterized in that:

   - the fuzzy branch (21A) of the cut-off (21) of the first elementary beam (20) is at least partially included in the second elementary beam (30);

   - the second elementary beam (30) exhibits a cut-off (31) comprising a sharp first branch (31A) and a fuzzy second branch (31B), the sharp branches (21B, 31A) of the first and second elementary beams forming between them a non-zero angle, the fuzzy branch of the cut-off of one of said elementary beams (20, 30) being at least partially included in the other of the beams.
3. Device according to Claim 1, wherein the cut-off (51) of the beam (50) comprises two branches forming between them a non-zero angle, notably lying between 10° and 60°, preferably an angle substantially equal to 15°, said branches being sharp.
4. Device according to one of the preceding claims, wherein the part (M) of said device capable of producing the first elementary beam (20) or the beam (50) comprises:

   - a light source (S),

   - a collection optical element (R1) arranged to collect the light from said source,

   - a folder (P) having a reflecting surface and a cut-off edge (P1, P2, P4) in order to receive only a part of the beam originating from the collection optical element and to thus produce a light beam with cut-off (20), and

   - a return optical element (R2; L), arranged to produce, towards the front, said light beam with cut-off (20; 50) .
5. Device according to Claim 4, wherein the return optical element (R2) is a non-imaging element.
6. Device according to one of Claims 4 to 5, wherein the cut-off edge (P1, P2, P3) of the folder (P) has, on the side intended to produce the second branch (21B), a main portion (P2), the end of which is in the extension (P1) of the side of the cut-off edge intended to produce the first branch (21A), and a peripheral portion (P4), the end of which forms, with said main portion (P2), an angle corresponding to the angle of inclination (α) of said first branch.
7. Device according to the preceding claim, wherein the part of said device capable of producing the first elementary beam (20) is turned by an angle of rotation (-α) of opposite sign and of absolute value substantially equal to the angle of inclination (α) of the second branch (21B) .
8. Device according to one of the preceding claims, wherein the projection on a screen at right angles to the optical axis (Z-Z') of the cut-off (31) of the second elementary beam (30) is more extended than the projection on this same screen of the cut-off (21) of the first elementary beam (20) .

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