EP2199664A1 - Lighting device for vehicle projector, allowing a pluratity of lighting functions or a variable function with only one light source - Google Patents

Abstract

The device has a pinpoint light source (3) i.e. LED, situated at the proximity of a focal point of an elliptical reflector (1) such that light rays (9) emitted by the source are reflected towards another focal point. An optical element (6) i.e. strip, has a rectangular plane surface whose zone i.e. concave lens, is situated at the proximity of the latter point to receive the rays with an angle of incidence. The element is movable, along a horizontal plane of the surface, transversally to an optical axis by an electric actuator e.g. electric motor, to displace the zone outside the rays.

Description

The invention relates to a projector lighting device, more particularly to a vehicle headlamp lighting device, the device being capable of providing a plurality of lighting functions and / or a variable lighting function with a single lighting device. lighting source.

The invention relates more particularly to vehicle headlamps equipped with one or more point light sources of the light-emitting diode or LED type. This type of light source is indeed more efficient from the point of view of consumption in comparison with more conventional light sources such as halogen or xenon lamps. The electrical power of a light source of the LED type adapted to a vehicle headlamp now varies between 20 and 30 W while that of a halogen source of comparable lighting power is of the order of 120 W. is even reasonable to think that LED modules with the same lighting power will soon be available with an electric power of the order of 5 to 10W In addition a new European legislation provides an obligation for new vehicles to be equipped with projectors. type DRL, or "Daytime Running Light", that is to say projectors intended to operate continuously during the day. The impact of lighting on fuel consumption will therefore increase as a draft European directive provides for the taxation of vehicle manufacturers as of 2012 per gram of CO ₂ emitted into the atmosphere above 120 gr / km. Given that a power consumption of a 120 W halogen floodlight corresponds to approximately 0.15 liter of fuel per 100 km, ie of the order of 5 to 6 gr of CO ₂ / km, the use of light-emitting diode-type light sources for vehicle projectors will be of increasing interest in the future.

The cost of LED lighting sources, however, remains quite high in comparison with conventional sources. The need to have several functions per projector, namely typically the functions "road" or "High Beam" (HB), "code" or "Low Beam" (LB) and "Daytime Running Light" (DRL) and therefore several light sources reinforces the issue of the cost of using LED sources.

In addition, the use of LED lighting sources implies for each source an electronic management module. The projector case will therefore be more complicated, bulkier and more expensive.

The document DE 10 2006 042 749 A1 discloses a vehicle headlighting device comprising an LED light source, an elliptical type reflector in a half-space with two foci. The LED source is placed at the first focus of the reflector near the reflector. The light emitted by the LED source is reflected by the reflector towards its second focus where a so-called folding reflective surface is positioned. This reflecting surface has an edge on the reflector side and an edge on the opposite side of the reflector. These edges are called "cut edges". A portion of the light beam reflected by the reflector encounters the reflecting surface and is reflected in accordance with its angle of incidence on the surface. Another part of the light beam passes over the cutoff edge (s) and is not deflected by the reflecting surface. The cutoff edge thus defines a boundary between the portion of the reflected beam and thus deflected and the nonreflected portion. A lens is positioned behind the reflective surface so that its focus corresponds to that of the elliptical reflector. The reflective surface with its cutoff edge (s) is called a folder because it deflects or "bends" part of the bundle to form a cutoff at the beam emitted by the lens. The folder is movable along an axis parallel to the optical axis of the reflector. This mobility ensures the function "road" or "High Beam" and function "code" or "Low Beam" with a single light source.

The document DE 10 2006 051 029 A1 discloses a device similar to that described above where the "folding" is movable along a vertical axis and an axis parallel to the optical axis of the elliptical reflector. These two movements make it possible to ensure the function "Road" or "High Beam" and the "code" or "Low Beam" function with a single light source.

The document DE 10 2006 042 750 A1 discloses a device similar to those described above wherein a "folder" is vertically movable and a vertical screen is movably arranged vertically as well. This device ensures the functions "road" and "code" with a single light source and moving the vertical screen also allows to vary the light intensity in the bottom of the beam of the projector.

The teachings of these documents act only at the level of the cut required for the "code" function. They mainly plan to move the cutoff edge to make the cut active or not and thus ensure the passage of the function "route" to the function "code" and vice versa. They do not allow, for example, other functions that will soon be necessary or desirable, such as the DRL function, or a function for varying the beam footprint depending on external parameters, such as the presence of a car in front of it. by the same light source.

The documents DE 103 05 624 and US 4,868,726 describe vertical caches.

The object of the invention is to propose a lighting device that makes it possible to perform several functions with a single light source or a limited number of light sources, and with more possibilities than in the state of light. art.

The invention consists of a projector lighting device, especially a vehicle, comprising: a reflector having a first focus, a second focus and an optical axis passing through the first and second focus; a light source located near the first focus of the reflector so that the light rays emitted by the light source are reflected by the reflector approximately to its second focus; a first optical element having a focal point and an optical axis, the focus being located near the second focus of the reflector, the first optical element being adapted to project the light rays emitted by the source and reflected by the reflector in a beam along its optical axis; a second optical element preferably comprising a generally planar surface, a zone of which is located near the second focus of the reflector so as to receive, with an angle of incidence, the light rays emitted by the source and reflected by the reflector; wherein the second optical element, preferably generally horizontal, is movable in the plane of its surface, in particular substantially transversely to the optical axis of the reflector, so as to be able to move said zone out of the light rays.

This device has the advantage of making it possible to provide lighting functions that are different from a simple displacement of the cutoff edge, and this with a single light source or a constant number of light sources in the case of parallel mounting of several devices. . By the proposed transversal arrangement, the number of functions can be quite high.

According to an advantageous characteristic, the surface of the second optical element comprises at least two zones positioned one beside the other transversely to the optical axis of the reflector, each zone being at least one of the following types: reflective, transparent , colored, scattering or divergent lens or a spatial combination of these different types.

According to an advantageous characteristic of the invention, the second mobile element is movable in a substantially horizontal plane, preferably in combined directions perpendicular to the optical axis and parallel to the optical axis.

According to an advantageous characteristic, the surface of the second optical element is of elongate shape, preferably substantially rectangular, with a longitudinal axis, comprising at least two zones distributed along the longitudinal axis, whose optical characteristics are different and selected from the following ones: : reflective, transparent, colored, diffusing or divergent lens or a spatial combination of these different types

According to an advantageous characteristic, the second optical element is movable in translation, preferably generally in a direction perpendicular to the optical axis of the reflector.

According to an advantageous characteristic, the surface of the second optical element is of elongated shape slightly curved along a main curve, preferably in a circular arc, and comprising at least two zones distributed along its main curve, the optical characteristics of which are different and selected from among the following: reflective, transparent, colored, diffusing or divergent lens or a spatial combination of these different types

According to an advantageous characteristic, the second optical element is rotatable along a sufficiently large radius as to ensure a movement of the zones which is transverse to the optical axis of the reflector.

According to an advantageous characteristic, the surface of the second optical element comprises a reflective zone with a so-called edge cutting edge crossing the optical axis of the reflector, preferably on the opposite side to the reflector.

According to an advantageous characteristic, the cutting edge has a variable profile in a direction generally perpendicular to the optical axis of the first reflector.

According to an advantageous characteristic, the cutting edge has a constant profile in a direction generally perpendicular to the optical axis of the first reflector.

According to an advantageous characteristic, the reflector comprises a curved reflecting surface, preferably elliptical, in a half-space limited by a plane, the first and second focus of the reflector being situated approximately in said plane, the second optical element being movable in said plane or parallel to said plan.

According to an advantageous characteristic, the second optical element is mobile with at least two indexed positions.

According to an advantageous characteristic, the second optical element is continuously movable, preferably between two indexed positions.

According to an advantageous characteristic, the surface of the second optical element comprises at least two optical markers corresponding to the indexed positions, the optical markers being preferentially made by metallization.

According to an advantageous characteristic, the second optical element is movable in translation and / or in rotation by means of an electric motor, for example a stepping motor, a piezoelectric motor or a solenoid, in particular with two specific actuators of the motor type. step or piezoelectric or solenoid, either with the combination of two of these types of actuators, or with a single piezoelectric motor by controlling the activation frequency appropriately.

According to an advantageous characteristic, the first optical element is of the reflector type, the optical axis of which crosses the optical axis of the reflector, preferably whose optical axis is perpendicular to the optical axis of the reflector.

According to an advantageous characteristic, the first optical element is a lens whose optical axis corresponds essentially to the optical axis of the reflector.

According to an advantageous characteristic, the second optical element is also essentially movable along the optical axis of the reflector, preferably in translation, by means of an actuator.

According to an advantageous characteristic, the device comprises a device for controlling the actuator of the second optical element along the optical axis, capable of displacing, preferably dynamically, a reflecting surface of the second optical element in order to compensate for changes in attitude. of the vehicle.

The folder according to the invention is preferably substantially flat and horizontal, possibly comprising transparent areas.

This folder is advantageously movable horizontally.

The folder may, if desired, be able to be rotated about a distant vertical axis.

The invention also relates to a vehicle headlight or taillight comprising a device as defined above.

The invention also relates to a vehicle equipped with such a projector or such a rear light.

Other features and advantages of the invention will appear in the following detailed description of the embodiments of the invention, given for information only and in no way limiting.

• La figure 1a est une vue schématique en plan et en coupe d'un premier exemple de dispositif d'éclairage pour projecteur de véhicule selon l'invention.
• La figure 1b est une vue schématique en élévation et en coupe du premier exemple de dispositif d'éclairage selon la figure 1a.
• La figure 2 est une vue schématique en élévation de l'élément optique mobile du dispositif des figures 1a et 1 b.
• La figure 3 est une vue schématique du principe de fonctionnement optique de la zone 6a de l'élément optique de la figure 2.
• La figure 4 est une vue schématique du principe de fonctionnement optique de la zone 6b de l'élément optique de la figure 2.
• La figure 5 est une vue schématique du principe de fonctionnement optique de la zone 6c de l'élément optique de la figure 2.
• La figure 6 est une vue schématique du principe de fonctionnement optique de la zone 6d de l'élément optique de la figure 2.
• La figure 7 est une vue schématique en élévation et en coupe d'un second exemple de dispositif d'éclairage pour projecteur de véhicule selon l'invention.
• La figure 8a est une vue schématique en élévation illustrant le principe de fonctionnement du dispositif de la figure 7 en position dite « route ».
• La figure 8b est une vue schématique en élévation illustrant le principe de fonctionnement du dispositif de la figure 7 en position dite « sélective ».
• La figure 8c est une vue schématique en élévation illustrant le principe de fonctionnement du dispositif de la figure 7 en position dite « touriste ».
• La figure 8d est une vue schématique en élévation illustrant le principe de fonctionnement du dispositif de la figure 7 en position dite « code ».
• La figure 8e est une vue schématique en élévation du dispositif de la figure 7 illustrant les repères optiques de positionnement de l'élément optique mobile.

In the following figures:

• The figure 1a is a schematic plan view in section of a first example of a vehicle headlamp lighting device according to the invention.
• The figure 1b is a schematic view in elevation and in section of the first example of a lighting device according to the figure 1a .
• The figure 2 is a schematic view in elevation of the mobile optical element of the device of Figures 1a and 1 b.
• The figure 3 is a schematic view of the principle of optical operation of the zone 6a of the optical element of the figure 2 .
• The figure 4 is a schematic view of the principle of optical operation of the zone 6b of the optical element of the figure 2 .
• The figure 5 is a schematic view of the principle of optical operation of the zone 6c of the optical element of the figure 2 .
• The figure 6 is a schematic view of the principle of optical operation of the zone 6d of the optical element of the figure 2 .
• The figure 7 is a schematic view in elevation and in section of a second example of a vehicle headlighting device according to the invention.
• The figure 8a is a schematic view in elevation illustrating the principle of operation of the device of the figure 7 in position called "road".
• The figure 8b is a schematic view in elevation illustrating the principle of operation of the device of the figure 7 in so-called "selective" position.
• The figure 8c is a schematic view in elevation illustrating the principle of operation of the device of the figure 7 in so-called "tourist" position.
• The figure 8d is a schematic view in elevation illustrating the principle of operation of the device of the figure 7 in the so-called "code" position.
• The figure 8e is a schematic view in elevation of the device of the figure 7 illustrating the optical positioning marks of the mobile optical element.

Embodiments of the invention are illustrated in the figures and described hereinafter with respect to a mounting position of the device in a vehicle as a projector. This type of application although preponderant is not limiting so that the terms used such as "horizontal", "vertical", "high", "low", "superior", "lower" for example, in order to describe the positions of the different elements are not absolute but rather to interpret in a relative manner describing the positions of the elements with respect to their arrangement in the figures. The described lighting devices could be mounted in other positions and / or for other applications. In addition, the relative positions of the various optical elements such as light sources, reflectors and lenses expressed for simplicity of understanding by alignment of the optical axes and / or correspondence of the respective foci are not to be interpreted accurately in the measurement where slight variations are conceivable or even desirable in order, among other things, to correct the non-perfect nature and certain optical aberrations of the optical elements or to obtain certain additional effects.

The figure 1a is a schematic plan view and section along a median plane of a first embodiment of the invention. It is a lighting device for a vehicle headlamp comprising an elliptical reflector 1 and symmetrical in rotation about its optical axis 2. The reflector comprises a reflective inner surface 12 whose profile in section along a plane passing through the axis 2 is an ellipse section. Its inner surface 12 corresponds to the section of ellipse visible at the figure 1a describing a rotation around the optical axis and symmetry 2 in a half-space. This half-space is limited by a plane containing the axis 2 and being horizontal. This reflector 1 has two foci along its axis 2. A light source 3 is positioned approximately at the location of the first focus and the second focus is referenced by the reference sign 4.

It should be noted that the reflective inner surface 12 of the reflector may not be perfectly elliptical and have one or more specific or complex profiles in order to optimize the light distribution in the lighting beam. This may imply that the reflector 1 is not perfectly symmetrical in revolution.

The light source 3 is of the light-emitting diode type or LED which emits the majority of its light energy towards the reflective inner surface 12 of the reflector 1. This type of light source has the particularity of being particularly compact to the point where it can be assimilated in an approximate manner to a point source. Other known types of light source can, however, also be considered.

The majority of the light rays emitted by the light source 3 are reflected by the reflective surface 12 of the reflector 1. By assimilating the light source to a point source located at the first focus of the reflector and by assimilating the reflector to a perfect elliptical reflector, the rays Reflected by the reflector all converge towards the second focus 4. In reality, the light source is not punctual and the shape of the reflective surface 12 is not necessarily perfectly elliptical so that the reflected rays do not all converge towards the second focus 4 but rather to an area close to the second focus 4.

A movable optical element 6 is disposed near the second focus 4 in the horizontal plane containing the optical axis and symmetry 2 of the reflector 1. This optical element 6 is better illustrated at the figure 1b which is a schematic view in elevation of the device of the figure 1a . The section is in the horizontal plane including the axis 2. The optical element 6 is movable in translation along its longitudinal axis 11 perpendicular to the optical axis 2 and included in the horizontal plane. The optical element comprises a substantially planar surface which itself comprises different optically different areas to provide different functions of the illumination device. The optical element 6 is actuated in translation along the axis X by an actuator 10 and in translation along the axis Z by an actuator 14. These actuators can be of the electric type such as for example an electric motor, a piezoelectric motor , or any other type of actuator known to those skilled in the art and adapted to move the optical element 6. The different optical zones of the optical element 6 may be of the reflecting type, transparent, transparent colored , scattering, lens, or a spatial combination of these different types, etc ...

Advantageously, the optical element 6 is displaceable in a substantially horizontal plane, according to combined movements perpendicular (s) to the optical axis 2 and parallel (s) to the optical axis 2, by means of a single piezoelectric motor, with appropriate control of the activation frequencies.

Guide means (not shown) in translation of the optical element must be provided in a manner known to those skilled in the art.

The light rays 7 reflected by the reflector 1 which converge towards the second focus 4 and which meet the surface of the optical element 6 are reflected or transmitted depending on the optical nature of the surface portion encountered. If the surface encountered is reflective, the spokes 7 will be reflected upwards with respect to the axis 2 as shown in FIG. figure 1a . The rays 9 reflected by the reflector not meeting the surface of the optical element 6 propagate downwards with respect to the axis 2, as is also illustrated in FIG. figure 1a .

A lens 5 is provided on the optical path of the device. This lens of the convex plane type has its focus corresponding to the second focus 4 of the reflector 1 and its optical axis coincides with the optical axis of the reflector so that the light rays coming from the focus 4 are transmitted substantially parallel to the optical axis 2. Other types of convergent lens are conceivable, such as a biconvex lens or convergent meniscus type. A reflector of the paraboloid mirror type is also conceivable. In this case, its optical axis would be substantially perpendicular or at least transverse to the axis 2 and its focus would be approximately coincident with the focus 4. Such a reflector would then reflect the light rays in a direction substantially parallel to its optical axis, that is to say substantially transversely or perpendicularly to the optical axis 2.

As can be seen in Figures 1a and 1b , the light rays coming from the reflector are inverted with respect to a vertical plane and also with respect to a horizontal plane after their passage towards the focus 4 and the optical element 6. An XYZ reference is represented at Figures 1a and 1b where the axis Z corresponds to the optical axis 2 and approximately to the axis of projection, the axis X corresponds to the perpendicular to the axis Z and contained in the plane delimiting the half-space of the reflector 1 and comprising the 11 axis of displacement of the optical element 6, and the Y axis corresponds to the perpendicular to the plane defined by the axes X and Z. As can be observed at the figure 1b , the rays reflected by the reflector 1 intersect the optical axis 2 at the optical element 6 and pass on the other side of the vertical plane or the plane containing the axis 2 and parallel to the Y axis. same phenomenon occurs with respect to the plane containing the axis 2 and parallel to the X axis. figure 1a shows in fact that the rays reflected by the reflector 1 intersect the plane in question and, for those not reflected by the optical element 6, pass on the other side of the plane. This phenomenon does not apply to the rays 7 reflected at the plane by the optical element, which remain on the same side of the plane.

The optical element 6 may comprise four or more distinct optical zones. These are illustrated in detail in Figures 2 to 6 .

The first zone 6a is of the concave plane lens type in order to diffuse the light rays. The principle of this phenomenon is illustrated in figure 3 . When the element 6 is positioned to present the area 6a to light rays from the reflector 1, they pass through the area 6a and are diffracted in a divergent manner so as to illuminate a large part of the lens. This generates an enlarged illumination beam which, combined with a reduction in the power of the light source, corresponds to the daylighting function commonly known as DRL (Daytime Running Light). It should be noted that the divergence function of the zone 6a can be reached by various known means, for example and non-exhaustively a diffusing surface treatment or a divergent microlens array.

The second zone 6b of the optical element 6 is a so-called "folding" reflecting surface. The optical principle of operation of this zone is illustrated in figure 4 the light rays coming from the reflector 1 meeting this surface are reflected at an angle to the vertical at the surface which is equal to that of the incident rays. These incident rays are sent back to the upper part of the lens. The rays not meeting the reflective surface 6b traverse the horizontal plane and evolve in the lower half-space without deflection to the lens. The boundary between the reflective zone 6b and the region of the horizontal plane traversed by the non-deflectable rays is physically formed by the leading edge and / or possibly rearward of the zone 6b and is called the cutting edge. It defines the boundary between the reflected rays and the non-reflected rays and influences the imprint of the beam projected by the device. Indeed, as illustrated in figure 1a , the rays 8 reflected by the folder are refracted by the upper part of the lens. These rays reflected by the folder will therefore generate rays projected by the lens whose imprint will be different from that which would be generated by these rays if they were not reflected by the folder. The reflected rays are projected by the upper part of the lens slightly inclined downwardly with respect to the optical axis whereas these rays would have been projected by the lower part of the lens slightly inclined upwards with respect to the optical axis if they had been transmitted without reflection. This effect can also be reinforced or influenced by various parameters such as, for example, a slight inclination of the folder with respect to the optical axis, a complex non-planar shape of the folder, a complex shape of the lens (or of a paraboloidal reflector). in place of the lens) and / or a slight offset of the folder along the Y axis relative to to the optical axis. The optical element 6 can be displaced along the axis Z corresponding to the optical axis by means of an actuator 14. These displacements make it possible to move the cutting edge forward or backward so as to modulate the height cut-off of the beam projected by the device. This function is particularly suitable for compensating for changes in inclination of the device such as the attitude of the vehicle on which the device is mounted. This adaptation may be punctual when starting the vehicle to compensate, for example, a large load of the trunk or may be permanent when driving the vehicle to compensate, for example, a change of attitude in a longitudinal plane when braking or accelerations. Moreover, the cutting edge does not have to be straight and perpendicular to the optical axis, it can indeed be inclined or have a complex profile in order to optimize the projected impression and / or to compensate for certain aberrations inherent to certain elements. optics. The reflective optical zone 6b may correspond to a so-called "code" or "low beam" function for crossing with other vehicles coming in the opposite direction, where the impression of the projected beam is cut in its upper part. An inclination of the cutting edge (not shown) makes it possible to obtain an imprint whose upper part varies along the X axis.

The third zone 6c of the optical element 6 is a partially transparent and partially reflecting surface. It has an L shape, where the L branches are transparent and the rest of the area is reflective. The reflective part is represented by the hatched area. This zone corresponds to a so-called "selective" function that makes it possible to vary the projected impression along the X axis so as to match the cut portion to a vehicle coming in the opposite direction. The reflecting surface will reflect light rays from the reflector (1) which will then be refracted by the lens (5). The reflective surface of the zone 6c will therefore limit the height of the beam on its left. Area 6c shown in figure 2 corresponds to a vehicle headlight. The projector on the opposite side shall have a zone 6c symmetrical about the Z axis. Each headlamp will therefore have in this function a lighting beam with a darkened area at the top of the other projector's side, respectively, thus forming a high window darkened in the lighting footprint of both projectors. The two respective zones 6c can then be moved in a continuous and controlled manner according to the position of the opposite vehicle so as to move the window transversely along the X axis. The movements of the optical elements of the two projectors in the "selective" function need not necessarily be identical. Indeed, it may be desired or necessary to expand the window according to the approximation of the opposite vehicle and thereby move the optical elements of the two projectors in a differentiated manner. As an alternative to the continuous displacement of the optical element 6 of the headlamp, the entire optical device of the headlight can be rotated along an axis substantially parallel to the axis Y. A displacement of the window along the axis Y can also be displaced along the optical axis or Z axis. Such a displacement is desirable or even necessary so that the window can follow an opposing vehicle approaching. The shape of the reflective part may be different from that of the figure 2 . The optical principle of operation is illustrated in figure 5 showing that some rays cross the surface without (or with very little) deviation and others are reflected according to the location of the area they encounter.

The fourth zone 6d of the optical element is a transparent surface or empty of any optical function. The optical principle of operation is illustrated in figure 6 which illustrates that all rays are transmitted without (or with very little) deviation. This position corresponds to a function called "road" or "High Beam", that is to say, a natural imprint uncut optical device.

The device described thus makes it possible to provide four lighting functions by means of a single light source. The passage from one function to another is done by means of the actuator 10 which displaces the optical element 6 in translation until the corresponding zone is in a position centered longitudinally on the focal point 4 of the optical device.

A second embodiment is illustrated in Figures 7 and 8a-8d . The architecture of this device is similar to that of the first embodiment, namely an elliptical reflector 1 in a half-space, a light source 3 illuminating essentially in the half-reflector space and positioned at the first focus of the reflector, an optical element 6 'movable transversely and longitudinally to the level of the second focus 4 of the reflector and a lens whose focus corresponds to the second focus 4 of the reflector. This device is distinguished from that of the first embodiment by the optical element 6 '. It comprises two optical zones: a first zone 6a 'transparent and a second zone comprising a major portion 6b' reflecting and a minor transparent portion 6c '. The border between the reflective portion 6b 'and the transparent portion 6c' corresponds to the cutoff edge. The device has four functions that are schematically illustrated in FIGS. Figures 8a to 8d . The optical element 6 'is enlarged therein for the sake of clarity.

The first function is illustrated in figure 8a where the transparent area is in function, that is, positioned transversely at the second focus of the reflector. This first function is the so-called "road" or "high beam" function generating a natural projection footprint of the optical device.

The second function is illustrated in figure 8b where the zones 6a 'and 6b' are straddling the region of the second focus where the rays coming from the reflector 1 pass. This function is said to be "selective" which makes it possible to vary along the X axis the projected imprint so as to Match the cut portion to a vehicle coming in the opposite direction. The transverse position of the optical element is continuously variable in order to be able to "follow" the position of the oncoming vehicle. Practically speaking, a portion of the rays reflected by the reflector are reflected by the reflecting surface 6b '. The reflection caused by the so-called "folding" reflective surface will reduce the height of the corresponding part of the impression. The height of the impression is thus reduced to its left. The progressive displacement of the optical element 6 'to the left corresponding to an increase of the active reflecting surface will modify the impression of the projected beam by widening the lowering of height to the right. This function in combination with a second symmetrical headlamp (with regard to the part of the optical element used to form the selective beam) makes it possible to form a darkened window by adapting the cutting and lowering of the beam to an opposite vehicle whose angular position relative to the vehicle illuminated by the device varies. Similarly to the previous example, a displacement of the window along the Y axis can also be combined with a displacement along the optical axis or axis Z. Such a displacement is desirable or necessary so that the window can follow an opposite vehicle approaching.

The third function is illustrated in figure 8c where the reflective rectangular portion of the zone 6b 'is active. It generates a cut across the entire width of the footprint. It may be a so-called "tourist" function that is that of a vehicle normally rolling on the left and rolling in a territory where one is driving on the right. The projected beam is cut across its entire width and thus avoids a glare that would otherwise take place in lighting of the type "code" or "crossing" for a roller on the left.

The fourth function is illustrated in figure 8d where the transparent area 6c 'is partially active. In this position, a part of the rays coming from the right part of the reflector 1 meets and crosses the transparent part 6c 'and is then refracted and projected towards the upper left part of the beam. Corresponding rays from the left reflector portion are reflected by the reflecting surface 6b '. Part of the rays can pass the front edge of the reflective surface. The resulting imprint is limited in height due to the cutting edge before the reflective surface, and in an inverted manner. The section of the cutting edge which is more advanced than the inclined edge limits the height on the right side of the impression and the inclined edge limits the height on the left side of the impression to a lesser extent and in a progressive manner. This is a "code" or "Low Beam" function for a vehicle intended for driving on the left.

This device makes it possible to achieve in a rather simple way a projector with four functions. The optical element should simply have a transparent surface and a reflective portion. The reflective part can be made quite simply by metallization on a support. For this purpose, it may be advantageous to make optical positions of position 13 at the same time as the reflecting surface. These are illustrated at figure 8e . The optical marks are advantageous for this application and are moreover quite simple to achieve in this context.

It should be noted that various combinations of lighting functions described are possible. In addition, other functions are also conceivable, such as example a flashing by providing a transparent area colored at the optical element. In this case, it may be necessary to reduce the power of the light source. A "fog" function is also possible by providing, for example, a larger reflective area, ie with a more advanced cutting edge (towards the lens) in order to direct the projected beam further downwards. It should also be noted that the presence of a reflective surface is not necessary. For example, an optical element with a diverging zone for a "DRL" function and a transparent zone for a "road" or "High Beam" function could be provided.

It should also be noted that the displacement of the optical element must be transversal but not necessarily in translation. Indeed, depending on various parameters such as the available space and the number of functions to be provided, one could provide an optical element slightly curved in the plane of its surface and rotate it according to a center of rotation located for example behind the reflector and the light source on the optical axis.

It should also be noted that the surface of the optical element which comprises the different optical zones does not necessarily have to be flat. On the contrary, depending on the different optical effects desired, one can imagine a slightly complex surface.

The transverse movement of the optical element need not be perpendicular to the optical axis and in the plane delimiting the half-space of the reflector. One could imagine a transversal movement but not perpendicular as well as in a plane forming a certain angle with the plane delimiting the half-space of the reflector, and this according to various parameters such as, for example, the maximum size. The optical element may also be located at a short distance from the plane delimiting the half-space of the reflector, as a function, for example, of the various imperfections and / or aberrations of the optical elements.

The described embodiments comprise a single light source. It is quite possible to envisage several light sources or several devices similar in parallel where the mobile optical elements would be mechanically linked and move by a single actuator.

Claims (16)

Projector lighting device, in particular for a vehicle, comprising: a reflector (1) having a first focus, a second focus (4) and an optical axis (2) passing through the first and second focus; a light source (3) located near the first focus of the reflector (1) so that the light rays emitted by the light source (3) are reflected by the reflector (1) approximately to its second focus; a first optical element (5) having a focal point and an optical axis (2), the focus being located near the second focus (4) of the reflector, the first optical element (5) being able to project the light rays emitted by the source (3) and reflected by the reflector (1) in a beam along its optical axis; a second optical element (6; 6 ') preferably comprising a generally planar surface having a zone located near the second focus (4) of the reflector (1) so as to receive, with an angle of incidence, the light rays emitted by the source (3) and reflected by the reflector (1); characterized in that the second optical element (6; 6 ') is movable in the plane of its surface, in particular substantially transversely to the optical axis (2) of the reflector (1), so as to be able to move said zone out of the light rays. Device according to the preceding claim, characterized in that the surface of the second optical element (6; 6 ') comprises at least two zones positioned one beside the other transversely to the optical axis (2) of the reflector (1 ), each zone being at least one of the following types: reflective, transparent, colored, diffusing or divergent lens or a spatial combination of these different types Device according to one of the preceding claims, characterized in that the surface of the second optical element (6; 6 ') is of elongated shape, preferably substantially rectangular, with a longitudinal axis (11), comprising at least two zones distributed along the longitudinal axis (11), whose optical characteristics are different and selected from the following: reflective, transparent, colored, diffusing or lens divergent or a spatial combination of these different types. Device according to one of the preceding claims, characterized in that the second optical element (6; 6 ') is movable in translation in a substantially horizontal plane, in parallel directions combined and perpendicular to the optical axis (2). Device according to the preceding claim, characterized in that the second optical element (6; 6 ') is movable in translation, preferably generally in a direction (11) perpendicular to the optical axis (2) of the reflector (1). Device according to one of the preceding claims, characterized in that the surface of the second optical element (6; 6 ') is elongated slightly curved in a main curve, preferably in a circular arc, and having at least two distributed zones along its main curve, whose optical characteristics are different and selected from the following: reflective, transparent, colored, diffusing or divergent lens or a spatial combination of these different types Device according to the preceding claim, characterized in that the second optical element (6; 6 ') is movable in rotation along a sufficiently large radius as to ensure a movement of the zones which is transverse to the optical axis (2) of the reflector ( 1). Device according to one of the preceding claims, characterized in that the surface of the second optical element (6 ') comprises a reflecting zone (6b') with a so-called cutting edge intersecting the optical axis (2) of the reflector (1), preferably on the opposite side to the reflector (1). Device according to the preceding claim characterized in that the cutting edge has a variable profile in a direction generally perpendicular to the optical axis (2) of the first reflector (1). Device according to claim 8, characterized in that the cutting edge has a constant profile in a direction generally perpendicular to the optical axis (2) of the first reflector (1). Device according to one of the preceding claims, characterized in that the reflector (1) has a curved, preferably elliptical, reflective surface (12) in a half-space limited by a plane, the first and the second focus of the reflector (1 ) being located approximately in said plane, the second optical element (6; 6 ') being movable in said plane or parallel to said plane. Device according to one of the preceding claims, characterized in that the second optical element (6; 6 ') is movable with at least two indexed positions. Device according to the preceding claim, characterized in that the first optical element is of the reflector type whose optical axis intersects the optical axis of the reflector, preferably whose optical axis is perpendicular to the optical axis of the reflector. Device according to the preceding claim, characterized in that the first optical element is a lens (5) whose optical axis substantially corresponds to the optical axis (2) of the reflector (1). Device according to one of the preceding claims, characterized in that the second optical element (6, 6 ') is also essentially movable along the optical axis (2) of the reflector (1), preferably in translation, by means of a actuator (14). Device according to one of the preceding claims, characterized in that the second optical element (6; 6 ') is movable in translation and / or in rotation, in particular in double movement, by means of an electric motor (10), by example a stepper motor, a piezoelectric motor or a solenoid, in particular by means of a single piezoelectric motor by controlling the activation frequency appropriately.

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