EP4264121A1

EP4264121A1 - Light-emitting module that images the illuminated surface of a collector, with a blocker of parasitic rays

Info

Publication number: EP4264121A1
Application number: EP21839985.5A
Authority: EP
Inventors: Corentin DEBAINE; Sylvain Giraud; Yves Gromfeld; Clement Olchewsky
Original assignee: Valeo Vision SAS
Current assignee: Valeo Vision SAS
Priority date: 2020-12-17
Filing date: 2021-12-16
Publication date: 2023-10-25
Also published as: KR20230106685A; FR3118125B1; CN116710699A; JP2023553723A; WO2022129420A1; US20240027047A1; US12117139B2; FR3118125A1

Abstract

The invention relates to a light-emitting module (102) comprising: a light source (104) able to emit light rays; a collector (106) with a reflective surface (102.6); an optical system (110) configured to project a light beam by imaging a portion of the reflective surface (102.6) located behind the light source (104); a screen (112) located in front of the light source (104), with a rear face (112.1) able to harvest light rays (114) emitted forward by the light source (104) and not reflected by the reflective surface (102.6); wherein the screen (112) comprises an end face (112.2) that is adjacent to the rear face (112.1) and that faces reflected light rays (116), and that is configured to avoid and/or absorb said reflected light rays.

Description

LIGHT MODULE IMAGING THE ILLUMINATED SURFACE OF A COLLECTOR WITH A BLOCKER OF INTERFERENCE RAYS

The invention relates to the technical field of lighting and signaling, more particularly for applications in the automotive field.

It is generally known to produce a cut-off lighting beam using one or more bending light modules. Such a light module conventionally comprises a collector with a reflective surface of revolution with an elliptical profile, in the shape of a cap in a half-space delimited by a horizontal plane. An essentially point-like light source, of the light-emitting diode type, is located at a first focal point of the reflecting surface and illuminates in the half-space in the direction of said surface. The rays are thus reflected in a convergent manner towards a second focal point of the reflecting surface. Another, generally flat, reflective surface with a cut-off edge at the second focal point provides upward reflection of rays which do not pass precisely through the second focal point, these rays then being refracted by a thick lens towards the bottom of the beam lighting. This reflective surface is commonly referred to as a "bend" in that it "bends" upward from the projection lens the rays that would otherwise form a top portion of the illumination beam. Such a light module has the disadvantage of requiring significant precision in the positioning of the folder and the cutting edge. Also, the projection lens must be a thick lens due to its short focal length, which increases its weight and complicates its production, such as shrinkage defects in particular. In addition, the collector has a certain height and, therefore, a certain overall height.

The published patent document WO 2020/025171 A1 discloses a light module, in particular for a motor vehicle, comprising a collector with a reflecting surface collecting and reflecting the light rays emitted by a light source into a light beam, similar to a light module with a bender. The light module also includes a projection optical system, such as a lens, specifically configured to project the light beam in question by forming an image of the reflective surface of the collector. To this end, the projection optical system has a focus located on the reflecting surface, for example at a rear edge of the latter so as to correctly image said edge and form a clean cut in the projected light beam. Certain rays emitted by the light source and not reflected by the reflective surface of the collector can however reach the projection optical system and degrade the projected light beam. For this purpose, a screen arranged in front of the light source is provided. However, the latter however presents certain difficulties in particular as regards its incidence on the rays reflected by the reflecting surface and meeting it and liable to degrade the photometry of the desired beam and in particular to create parasitic rays in the beam.

The aim of the invention is to overcome at least one of the drawbacks of the aforementioned state of the art.

The subject of the invention is a light module comprising a light source capable of emitting light rays; a collector with a reflecting surface configured to collect and reflect part of the light rays, called reflected rays, into a reflected light beam along an optical axis of the light module; an optical system configured to project at least the majority of the reflected light beam into a projected light beam by imaging a part of the reflecting surface located, in a general direction of propagation of the reflected light beam along the optical axis, at the rear of the light source; a screen located at the front of the light source, in the general direction of propagation of the light beam along the optical axis, with a rear face arranged so as to collect direct light rays emitted forwards by the light source and non-reflected by the reflective surface; remarkable in that the screen comprises an end face at a free end of said screen, facing the reflected light rays, arranged so as to be away from the said reflected light rays and/or to absorb a part of said reflected light rays.

Thus, the invention makes it possible to optimize the screen function of blocking the rays emitted directly by the light source, that is to say not reflected by the reflective surface of the collector, and likely to reach the optical system of projection and to degrade the projected light beam, in particular at the level of the cutoff in the case of a cutoff light beam. Indeed, this blocking of direct rays, in particular by absorption or appropriate deflection, is achieved by avoiding harmful interference with the projected light beam.

Advantageously, the end face is adjacent to the rear face.

Advantageously, the projected light beam may have a cut-off line, preferably horizontal. The invention is particularly advantageous for such a beam, the dazzling parasitic rays being reduced, or even eliminated.

The collector may have a rear edge whose profile projected by the optical system forms said cut-off line. This eliminates the need for a cache, in particular a folding machine for creating the cut line.

Advantageously, the optical system can have a focal zone located on the reflective surface of the collector, in particular at the rear of the light source. This simply makes it possible to image the part of the reflection surface located behind the light source.

More advantageously, the focal zone can be located at a rear edge of said reflective surface.

In general, this focal zone can be a focal point, also called a focal point, or can be a focal line, also called a line of focal points.

The optical system can comprise a lens, or one or more mirrors, the focal zone of which is that of the optical system.

Below are described advantageous but non-limiting modes of the invention, one or more of these modes being able to be combined with each other.

The collector may be a concave reflector.

At least some of these reflected rays have angles of inclination with respect to said optical axis which are less than or equal to 10°. This makes it possible to be in the so-called Gaussian conditions, thus allowing stigmatism.

According to an advantageous embodiment of the invention, the end face of the screen may have a length, in the general direction of propagation of the light beam along the optical axis, less than or equal to 1 mm, making it possible to avoid the rays reflected light.

According to an advantageous embodiment of the invention, the end face of the screen may have an inclination with respect to the nearest reflected light rays, so as to be away from said reflected light rays. It is a simple way to make the screen while minimizing its interference with the reflected rays.

Advantageously, the reflected rays may have an inclination with respect to the optical axis, and the inclination of the end face of the screen with respect to the optical axis may be greater than the inclination of the light rays reflected closer to said end face, or even directly adjacent to this end face, so as to be away from said reflected light rays.

The end face may be an inclined face facing the optical system. In particular, it can join said rear face at an acute angle so as to form an edge. This further minimizes the risk of interference with the reflected beam.

In particular, this ridge can be arranged so that at this ridge the lowest rays of the reflected beam pass skimming this ridge, the other reflected rays passing above. The blocking role is thus optimized by interfering as little as possible, or even not at all, with the reflected light beam. The projected beam is optimized.

According to an advantageous mode of the invention, the optical system has a focal zone located on the reflective surface of the collector, at the rear of the light source.

According to an advantageous mode of the invention, the end face of the screen can have a reflectance in the visible light spectrum of less than 0.3. This characteristic can apply to the end face in particular when said end face is not tilted.

According to an advantageous mode of the invention, the screen is opposite the reflecting surface.

According to an advantageous mode of the invention, the screen extends transversely to the optical axis from a plate supporting the light source. For example, the screen can be a separate part from the plate. Alternatively, the screen can be an integral part of the plate.

According to an advantageous embodiment of the invention, the screen is an outgrowth of a light source cooling radiator, said radiator being located on a face of the plate opposite the light source.

According to an advantageous embodiment of the invention, the screen is a first screen located on the same side of the optical axis as the light source, said light module comprising a second screen located on the opposite side of the optical axis and at the front of the reflective surface, and comprising a rear face configured to collect direct light rays emitted forwards by the light source, not reflected by the reflective surface and passing next to the end face of the first screen and between said end face and the reflective surface.

According to an advantageous embodiment of the invention, the second screen comprises an end face at a free end of said second screen and facing the reflected light rays, arranged so as to be away from the reflected light rays , absorbing and/or reflecting towards a lower half of the reflected light beam said reflected light rays. Advantageously, the end face of the second screen is adjacent to the rear face of said second screen.

According to an advantageous embodiment of the invention, the end face of the second screen has an inclination with respect to the nearest reflected light rays, so as to be away from said reflected light rays.

Advantageously, the reflected rays have an inclination with respect to the optical axis, and the inclination of the end face of the second screen with respect to the optical axis is greater than the inclination of the reflected light rays directly adjacent to said end face, so as to be away from said reflected light rays.

According to an advantageous mode of the invention, the end face of the second screen has a reflectance in the visible light spectrum of less than 0.3. This characteristic can apply to the end face of the second screen in particular when said end face is not inclined.

According to one embodiment of the invention, the end face of the second screen has a reflectance in the visible light spectrum substantially equal to 0.9. Here, "substantially equal" means equality within +/- 10%.

According to an advantageous embodiment of the invention, the end face of the second screen has a convex curvature capable of reflecting towards the lower half of the light beam the reflected light rays.

According to an advantageous mode of the invention, the second screen is located at the front of the reflective surface of the collector.

According to an advantageous mode of the invention, the second screen is supported by the collector. For example, the second screen can be formed integrally with the manifold.

The invention also relates to a motor vehicle headlamp, comprising a light module according to the invention.

The measures of the invention are advantageous in that they make it possible to avoid disturbing the light beam projected by parasitic light rays, and this in an effective and simple manner. In particular, the fact of providing a screen with a specially sized and/or configured end face to avoid parasitically returning rays reflected by the reflecting surface into the projected light beam.

Also, the fact of providing a second screen on the side opposite the first screen with respect to the optical axis of the light module makes it possible to control the part of the rays emitted forwards by the light source and not reflected by the reflecting surface.

is a schematic representation, in side view, of a light module according to a first embodiment of the invention;

is a perspective view of the light module manifold of the ;

is a view of the interior surface of the light module collector of the , from the outside along the optical axis;

is a graphical representation of the light image of the illumination beam produced by the light module of the ;

is a schematic representation, in side view, of a light module according to a second embodiment of the invention;

is a schematic representation, in side view, of a variant of the light module of the second embodiment of the invention of the ;

is a schematic representation, in side view, of a light module according to a third embodiment of the invention;

corresponds to the of the third embodiment of the invention, illustrating the inclination of the end faces of the screens;

is a schematic representation, in side view, of a light module according to a fourth embodiment of the invention;

is a schematic representation, in side view, of a light module according to a fifth embodiment of the invention;

is a schematic representation, in top view, of a light module according to the fifth embodiment of the invention while applying to each of the different embodiments of the invention;

is a perspective representation of the embodiment of a screen with an inclined end face and integrally formed with a cooling radiator;

is a perspective representation of the embodiment of a screen with a more inclined end face and integrally formed with a cooling radiator.

detailed description

Figures 1 to 4 illustrate a first embodiment of a light module according to the invention.

The is a schematic representation, in side view, of the light module and its principle of operation. The light module 2 essentially comprises a light source 4, a collector 6 capable of reflecting the light rays emitted by the light source 4 to form a light beam along an optical axis 8 of the light module, and a projection lens 10 of said beam . The optical axis 8 of the light module coincides with the optical axis of the projection lens 10. Other projection optical systems than the projection lens are possible, such as in particular one or more mirrors.

Here, as generally according to the invention, the light source 4 is advantageously of the semiconductor type, such as in particular an electroluminescence diode. In particular, the light source 4 emits light rays in a half-space delimited by the main plane of said source, in a main direction perpendicular to said plane and to the optical axis 8.

The collector 6 comprises a main body 6.1 in the form of a shell or cap, and a reflecting surface 6.2 on the inside face of the main body 6.1. The reflective surface 6.2 can advantageously have a profile of the elliptical or parabolic type. It is advantageously a surface of revolution around an axis parallel to the optical axis. Alternatively, it may be a free-form surface. It can also include several sectors. The manifold 6 in the form of a shell or cap is advantageously made of materials having good heat resistance, for example glass or synthetic polymers such as polycarbonate (PC) or polyether imide (PEI).

The expression "parabolic type" generally applies to reflectors whose surface has a single focal point, that is to say a zone of convergence of the light rays such that the light rays emitted by a light source placed at the level of this convergence zone are projected at a great distance after reflection on the surface. Projected at a great distance means that these light rays do not converge on an area located at least 10 times the dimensions of the reflector. In other words, the reflected rays do not converge towards a convergence zone or, if they do converge, this convergence zone is located at a distance greater than or equal to 10 times the dimensions of the reflector. A parabolic-type surface may therefore have parabolic portions or not. A reflector having such a surface is in particular to be used alone to create a light beam.

The light source 4 is arranged at a focal point of the reflecting surface 6.2 so that its rays are collected and reflected into a reflected light beam along the optical axis. At least some of these reflected rays have angles of inclination α with respect to said optical axis which are less than or equal to 10°, so as to be under the so-called Gaussian conditions, making it possible to obtain a stigma, that is i.e. sharpness of the projected image. These are advantageously the rays reflected by the rear part of the reflecting surface 6.2.

The projection lens 10 is advantageously a plano-convex lens, that is to say with a flat input face 10.1 and a convex output face 10.2. The lens 10 is said to be thin, for example less than 6 mm, due to the slight inclination of the rays to be deflected. The lens 10 has a focal point 10.3 which is located along the optical axis 8, at the level of the light source 4 or even behind said source. In this case the focus 10.3 is located on the reflective surface 6.2 of the collector 6, more precisely at its rear edge, here also the lower edge.

The reflecting surface, if it is of the elliptical type, has a second focus 6.3 located at the front of the lens 10 and at a distance from the optical axis 8. It should be noted that it is also possible for this focus to be located at the rear of the lens and/or on the optical axis, preferably close to the lens, so as to reduce the width of the beam at the level of the entrance face of the lens.

The light module 2 comprises a screen 12 arranged at the front of the light source 4 and facing the reflective surface 6.2 of the collector 6, with a rear face 12.1 able to collect the direct light rays 14 emitted towards the before directly by the source in question 4, that is to say not meeting the reflective surface 6.2. Such a measurement is useful for avoiding the presence of parasitic light rays liable to participate in the formation of the light beam without however being properly speaking imaged. These direct rays 14, in particular those which are parallel or quasi-parallel to the optical axis 8, will then potentially illuminate an upper part of the light beam, which is not desirable in the case of an illumination beam cut off.

The rear face 12.1 of the screen 12 is advantageously opaque in order to absorb the direct rays 14, emitted forwards directly by the light source 4, it being understood that it is also possible for it to be reflective in order to reflect these rays towards an absorption zone.

The screen 12 extends along a main transverse direction, advantageously perpendicular to the optical axis 8. It has an end face 12.2 facing the rays 16 reflected by the reflective surface 6.2. The end face 12.2 is adjacent to the rear face 12.1. One can observe at the that among the rays 16 reflected by the reflective surface 6.2, the closest rays directly adjacent to the end face 12.2 are only slightly disturbed by said surface due to its small width in the direction of the optical axis 8 The reflected rays 16 incident on this end face 12.2 are absorbed, reflected or a combination of the two, depending on the optical reflectance properties of said face. The luminous flux associated with these rays is reduced so that the part of these reflected rays is negligible. For this purpose, the width of the end face 12.2 is advantageously less than or equal to 1mm.

In practice, such a thin screen 12, in the form of a blade, can be made from a portion of sheet metal, the thickness of which forms the width of the screen 12.

The is a rear view, in perspective, of the collector 6 of the light module 2 of the . One can observe the shell shape or cap of the main body 6.1, as well as the fact that the reflecting surface (not visible) has a front edge 6.2.1 and a rear edge 6.2.2. Given the fact that the main body 6.1 and consequently the reflective surface 6.2, form a shell, in particular globally symmetrical in revolution. This shell is delimited by a plane, the plane in question includes part of the rear edge 6.2.2. The latter extends laterally on either side of the axis of revolution. When the reflective surface 6.2 is illuminated by the light source, it is then illuminated over its entire surface, the latter being delimited by the front 6.2.1 and rear 6.2.2 edges.

The is a representation of the light intensity at the reflective surface 6.2 seen from the outside, along the optical axis. More specifically, surface illuminance, ie the power of striking electromagnetic radiation per unit area perpendicular to its direction, expressed in W/m ² . The zone 6.2.3 covering the majority of the surface, corresponds to lower illuminations while the central zone 6.2.4 corresponds to greater illuminations. It can be seen that zone 6.2.3 is clearly delimited by edges 6.2.1 and 6.2.2. In other words, the illuminated surface 6.2 naturally has sharp edges capable of forming cuts in the projected lighting beam imaging this surface.

The is a graphical representation of the image projected by the light module of the , in particular on a vertical screen located 25 meters from the light module. The horizontal axis and the vertical axis intersect at the optical axis of the light module. The curves are isolux, that is to say correspond to the zones of the light beam which have the same illumination expressed in lux. The curves in the center correspond to a higher level of illumination than at the periphery. It can be observed that the light beam produced has a horizontal cutoff, essentially at the level of the horizontal axis, slightly below, in particular by 1 degree. The cut is substantially straight. In any case, the horizontal cut is made by the edge 6.2.2 ( ) which is the trailing edge ( ) of the reflective surface 6.2 of the collector 6.

The is a schematic representation, in side view, of a light module according to a second embodiment of the invention. The reference numbers of the first embodiment of the light module (FIGS. 1 to 4) are used to designate the same elements or corresponding elements, these numbers however being increased by 100. Reference is also made to the description of these elements in relation to figures 1 to 4.

The second embodiment is similar to the first embodiment and differs therefrom essentially in that the screen 112 is solid, that is to say does not form a thin blade like the screen 12 at the . Given the massiveness of the screen 112, the end face 112.2 has a length along the direction of the optical axis 108 sufficient to disturb, by reflection of reflected rays 116 on said end face 112.2, the light beam reflected, and thus the projected light beam. For this reason, the end face 112.2 is angled toward the optical system relative to the optical axis 108 more than the directly adjacent reflected rays 116, so as to avoid the rays in question. In this way, only the rear face 112.1 of the screen 112 collects the direct rays 114, emitted forwards directly by the light source 104.

As can be seen, the light source 104 is arranged on a plate 118 which can also support the screen 112. This measure is applicable to the other embodiments, in particular the first mode.

As is also visible in the , the projection lens 110 is of the biconvex type, namely that each of the input 110.1 and output 110.2 faces is convex. It is understood that the plano-convex lens of the first mode is applicable to this second embodiment and vice versa.

The represents a variant of the second embodiment at the . According to this variant, the screen 112' is integrally formed with a radiator 120 for cooling the light source 104. The latter is arranged under the plate 118', that is to say on one of the two main faces of said plate. 118', opposite the other of said two faces, supporting the light source 104. In this case, the plate 118' has an orifice through which the screen 112' extends, it being understood however that it is also possible that the screen 112' extends in front of the plate 118'.

Generally according to the invention, as here, the plate 118' can be a printed circuit board carrying the light source. Provision can also be made for the light source to be mounted directly on the radiator and connected to the printed circuit board by tracks, in particular wire bonding.

The is a schematic representation, in side view, of a light module according to a third embodiment of the invention. The reference numbers of the second embodiment of the light module ( ) are used to designate the same elements or corresponding elements, these numbers however being increased by 100. Reference is also made to the description of these elements in the context of the second embodiment.

The light module 202 according to this third embodiment comprises a second screen 222, separate from the first screen 212 and located on one side of the optical axis 208 which is opposite to that where the first screen 212 is located. The second screen 222 is configured to block the light rays 214.2 emitted forward by the light source, not reflected by the reflective surface and passing beyond the first screen 212. For this purpose, the second screen 222 comprises a rear face 222.1 collecting these rays 214.2 . Similar to the first screen 212, the second screen 222 extends along a main transverse direction, advantageously perpendicular, to the optical axis 208. It comprises an end face 222.2 facing the rays 216 reflected by the surface reflective 206.2 of the collector 206. This end face 222.2 is directly adjacent to the rear face 222.1. It is inclined with respect to the optical axis 208 more than the closest reflected rays 216, that is to say directly adjacent to the face in question, so as to avoid these rays in question. In other words, these rays pass in front of the edge formed by the intersection of the rear face 222.1 with the end face 222.2, without encountering said end face 222.2. These rays are thus not deflected. Only the direct rays 214.2, emitted forwards directly by the light source, encountering the rear face 222.1 of the second screen are blocked by absorption, reflection or a combination of the two.

The essentially corresponds to the , namely a schematic representation, in side view, of a light module according to the third embodiment of the invention, illustrating the inclinations of the end faces of the first and second screens 212 and 222.

It can be observed that the rays 216 reflected by the reflective surface 206.2 of the collector 306 have angles of inclination α ₁ and α ₂ with respect to the optical axis 208, the angle α ₁ relating to the rays passing below the optical axis 208 and the angle α ₂ relating to the rays passing above the optical axis 208. The end face 212.2 of the first screen 212, located below the optical axis 208 is inclined at an angle β ₁ > α ₁ . Similarly, the end face 222.2 of the second screen 222, located above the optical axis 208 is inclined at an angle β ₂ >α ₂ . For the two end faces 212.2 and 222.2, the inclinations are considered with respect to an edge corresponding to the intersection of the rear face 212.1 or 222.1 with the end face 212.2 or 222.2. In other words, the inclinations β ₁ and β ₂ of each of the end faces 212.1 and 222.1 are such that each of said faces gradually moves away from the reflected rays 216 passing directly in front of the edge formed by the intersection of the rear face 212.1 or 222.1 with the end face 212.2 or 222.2, moving away from said edge in the direction of propagation of the reflected rays 216.

The is a schematic representation, in side view, of a light module according to a fourth embodiment of the invention. The reference numbers of the third embodiment of the light module ( ) are used to designate the same elements or corresponding elements, these numbers however being increased by 100. Reference is also made to the description of these elements in the context of the third embodiment.

The light module 302 according to the fourth embodiment differs from the third embodiment, essentially in that the end faces 312.2 and 322.2 of the first and second screens 312 and 322, respectively, are not inclined more than the reflected rays. 316 passing close to said faces but have light absorption properties, expressed by a reflectance rate for visible light less than or equal to 30%, preferably 20%, even more preferably 10%. This means that the reflected rays 316 from the ends of the light beam directed towards the lens 310 encountering the end faces 312.2 and 322.2 are absorbed, at least for the most part. If there are reflections, these are minor and negligible.

The is a schematic representation, in side view, of a light module according to a fifth embodiment of the invention. The reference numbers of the fourth embodiment of the light module ( ) are used to designate the same elements or corresponding elements, these numbers however being increased by 100. Reference is also made to the description of these elements in the context of the fourth embodiment.

The light module 402 according to the fifth embodiment differs from the fourth embodiment, essentially in that the end face 422.2 of the second screen 422 is rounded and reflective.

As is visible at the , the direct rays 414.2 meeting the end face 422.2 are reflected towards a lower part, in this case the lower half, of the projection lens 410. The inclination of the reflected rays is such that these rays will be projected towards a lower part of the light beam. With reference to the illustrating the light image of the illuminating beam produces a light module such as that of the but also in FIGS. 5 to 10, the rays reflected by the end face 422.2 of the second screen will, once projected by the projection lens 410, participate in the formation of the light image at a distance from the horizontal cut-off edge. These rays will therefore not significantly disturb the light image produced. This measure also makes it possible to optimize light output by recovering light that would otherwise be lost. The reflective properties of the end face can also be obtained easily when the screen is made of a naturally reflective material such as aluminum.

The is a schematic representation, in top view, of the light module according to the fifth embodiment of the invention, while applying to each of the different embodiments of the invention.

It can be observed that the first screen 412 has a width, in a direction perpendicular to the optical axis 408, which is limited and determined by the light beam formed by the rays 414 emitted forwards directly by the light source 404 and capable of to meet the lens 410. It is also observed that the second screen 422 has a width, in the direction perpendicular to the optical axis 408, which is greater than that of the first screen 412, determined by the light beam formed by the rays 416 reflected by the reflective surface 406.2 of the collector 406, and likely to meet the lens 410. For this purpose, the second screen 422 can have a curved profile in the plane of view of the . In this case, the rear face 422.1 of the second screen has a concave curved profile.

The is a perspective representation of an embodiment of a screen with an inclined end face and integrally formed with a cooling radiator, as in the second embodiment in Figures 5 and 6.

One can observe at the a plate 118 supporting several light sources 104 and a screen 112 arranged in front of each of the light sources 104. In this case the screens 112 are integrally formed with a heat sink made of a heat-conducting material such as aluminum or a specific plastic material. The geometry of the screen 112 located in the center of the figure is schematized by an envelope in the shape of an inverted U. One can observe the inclination of an angle β ₁ .

The is a perspective representation of an embodiment of a screen with an inclined end face and integrally formed with a cooling radiator, as in the second embodiment in Figures 5 and 6, as an alternative to the .

It can be observed that the end face 112.2 has an inclination at an angle β ₁ greater than at the . Also, the end face 112.2 is confused with a front face of the screen unlike the where the screen has a separate front face.

In general, the various light modules described above can be integrated into a lighting device in combination with other light modules. Also, for reasons of clarity of presentation, the light source and the collector are each presented as unique. It is however understood that certain light modules according to the invention may comprise several light sources and/or several collectors, in particular several collectors arranged side by side, each having a light source and an associated screen.

Claims

Light module (2; 102; 202; 302; 402) comprising:
- a light source (4; 104; 204; 304; 404) capable of emitting light rays;
- a collector (6; 106; 206; 306; 406) with a reflecting surface (6.2; 102.6; 202.6; 302.6; 402.6) configured to collect and reflect part of the light rays, called reflected light rays, into a reflected light beam along an optical axis (8; 108; 208; 308; 408) of the light module;
- an optical system (10; 110; 210; 310; 410) configured to project at least the majority of the reflected light beam into a projected light beam by imaging a part of the reflecting surface (6.2; 102.6; 202.6; 302.6; 402.6) located, in a general direction of propagation of the light beam reflected along the optical axis (8; 108; 208; 308; 408), at the rear of the light source (4; 104; 204; 304; 404);
- a screen (12; 112; 212; 312; 412) located in front of the light source (4; 104; 204; 304; 404), following the general direction of propagation of the light beam along the optical axis ( 8; 108; 208; 308; 408), with a rear face (12.1; 112.1; 212.1; 312.1; 412.1) arranged so as to collect direct light rays (14; 114; 214.1; 314.1; 414.1) emitted towards the forward by the light source (4; 104; 204; 304; 404) and not reflected by the reflecting surface (6.2; 102.6; 202.6; 302.6; 402.6);
characterized in that
the screen (12; 112; 212; 312; 412) comprises an end face (12.2; 112.2; 212.2; 312.2; 412.2), at a free end of the screen and facing the light rays (16; 116; 216; 316; 416), arranged so as to be away from said reflected light rays and/or to absorb a part of said reflected light rays.
Light module (6) according to claim 1, in which the end face (12.2) of the screen (12) has a length, in the general direction of propagation of the light beam along the optical axis (8), less or equal to 1mm, making it possible to avoid the reflected light rays (16).
Light module (102; 202) according to claim 1 or 2, wherein the reflected rays have an inclination with respect to the optical axis, and wherein the end face (112.2; 212.2) of the screen (112; 212) has an inclination, with respect to the optical axis, greater than the inclination of the reflected rays (116; 216) adjacent to said end face, so as to be away from said reflected light rays.
Light module (2; 102; 202; 302; 402) according to one of Claims 1 to 3, in which the optical system (10; 110; 210; 310; 410) has a focal zone (10.3; 110.3) located on the reflecting surface (6.2; 102.6; 202.6; 302.6; 402.6) of the collector (6; 106; 206; 306; 406), at the rear of the light source (4; 104; 204; 304; 404).
Light module (302; 402) according to one of Claims 1 to 4, in which the end face (312.2; 412.2) of the screen (312; 412) has a reflectance in the visible light spectrum of less than 0.3.
Light module (2; 102; 202; 302; 402) according to one of Claims 1 to 5, in which the screen (12; 112; 212; 312; 412) faces the reflecting surface (6.2; 102.6; 202.6; 302.6; 402.6).
Light module (102; 202; 302; 402) according to one of Claims 1 to 6, in which the screen (112; 212; 312; 412) extends transversely to the optical axis (108; 208; 308 ; 408) from a plate (118; 218; 318; 418) supporting the light source (104; 204; 304; 404).
Light module (102) according to claim 7, in which the screen (112') is an outgrowth of a radiator (120) for cooling the light source (104), said radiator being located on one side of the plate ( 118) opposite the light source (104).
Light module (202; 302; 402) according to one of Claims 1 to 8, in which the screen (212; 312; 412) is a first screen located on the same side of the optical axis (208; 308; 408 ) that the light source (204; 304; 404), said light module comprising a second screen (222; 322; 422) located on the opposite side of the optical axis (208; 308; 408) and at the front of the reflective surface (206.2; 306.2; 406.2), and comprising a rear face (222.1; 322.1; 422.1) configured to harvest direct light rays (214.2; 314.2; 414.2) emitted forward by the light source (204; 304); 404), not reflected by the reflective surface (206.2; 306.2; 406.2) and passing next to the end face (212.2; 312.2; 412.2) of the first screen (212; 312; 412) and between this face of extremity and the reflective surface.
A light module (202; 302; 402) according to claim 9, wherein the second screen (222; 322; 422) comprises an end face, (222.2; 322.2; 422.2) at a free end of the second screen and facing -to the reflected light rays (216; 316; 416), arranged so as to be away from said reflected light rays, to absorb and/or reflect towards a lower half of the reflected light beam said reflected light rays.
Light module (202) according to claim 10, in which the reflected rays have an inclination with respect to the optical axis, and in which the end face (222.2) of the second screen (222) has an inclination with respect to the optical axis, greater than the inclination of the reflected rays (216) adjacent said end face, so as to be away from said reflected light rays.
Light module (302) according to claim 10, in which the end face (322.2) of the second screen (322) has a reflectance in the visible light spectrum of less than 0.3.
Light module (402) according to claim 10, in which the end face (422.2) of the second screen (422) has a convex curvature able to reflect the reflected light rays towards the lower half of the light beam.
Light module (202; 302; 402) according to one of Claims 9 to 13, in which the second screen (222; 322; 422) is located in front of the reflective surface (206.2; 306.2; 406.2) of the collector (206; 306; 406).
Light module (202; 302; 402) according to one of Claims 9 to 14, in which the second screen (222; 322; 422) is supported by the collector (206; 306; 406).
Vehicle headlamp comprising a light module according to one of the preceding claims.