This application claims priority to French Application No. 1351491 filed Feb. 21, 2013.
1. Field of the Invention
The present invention relates notably to a lighting and/or signaling unit. A preferred application relates to the motor vehicle industry for the production of lighting and/or signaling devices, notably vehicle headlights.
2. Description of the Related Art
In the motor vehicle domain, lighting modules or headlights are known, among which there are traditionally, mainly: low beams, or code lights, long-range main beams, or even fog beams. The document EP-A1-2525142 gives an example of an optical unit that can produce a lighting function and that comprises a light source of light-emitting diode type (hereinafter referred to by its acronym LED) and a lens of the planar input diopter/convex output diopter with elliptical profile type, the LED being placed at an object focus of the output diopter.
Implementing these lighting or signaling devices entails having a lens suited to each function and therefore a plurality of lenses, each specific, and through each of which an output beam can be emitted toward the area of space to be illuminated, in a preferred direction constituting the optical axis of the device and according to very often standardized lighting or signaling parameters.
The invention makes it possible to at least partly resolve the drawbacks of the current techniques.
One aspect of embodiments of the invention relates to a lighting and/or signaling unit, notably for a motor vehicle, comprising a first light source and an optical element comprising an input diopter and an output diopter, the optical element being configured to enable the emission of a first output light beam by the output diopter on reception of a first input light flux, generated by the first light source, by the input diopter, wherein it comprises a second light source, the optical element being configured to enable the emission of a second output light beam by the output diopter on reception of a second input light flux, generated by the second light source, by the input diopter, the output diopter comprising a first portion matched more particularly to the first light source and a second portion matched more particularly to the second light source.
Thus, the invention pools the input diopter and the output diopter for the use of a plurality of sources. This is made possible through the adaptation of the output diopter which characteristically comprises two portions, each more particularly suited to a light source. Specifically, one of the portions is designed in relation to one light source, whereas the other portion is designed in relation to the other light source. For example, the first portion can be a surface having a focus or a focal line passing through one of the light sources, and the second portion can be a surface having a focus or a focal line passing through the other of the light sources.
According to one embodiment, the first portion is elliptical and at a first focus thereof is located the first light source. According to one embodiment, the second portion is also elliptical and at a first focus thereof is located the second light source, the first foci of the first elliptical portion and of the second elliptical portion being distinct.
According to one embodiment, the first light source and the second light source form a pair of sources configured for their mean emission directions to be parallel and being spaced apart from one another in a direction at right angles to their mean emission directions.
According to a preferred embodiment, the first portion and the second portion are located, on either side, and advantageously symmetrically in relation to a base plane passing through the middle of a segment defined by the pair of sources and parallel to the mean emission directions, the first portion and the second portion being able, for example, to be elliptical as described previously.
Preferentially, the light source is formed by at least one photoemitter of a light-emitting diode and the second light source is formed by at least one other photoemitter of the light-emitting diode.
By this means, the sources are effectively formed and are on a single LED which can then fulfill two lighting and/or signaling functions.
Other options are given hereinbelow, all the options of the invention being able to be implemented independently or in association according to all possible combinations:
the output diopter comprises a cylindrical surface defined by a generatrix at right angles to the mean emission directions and by a guiding curve formed from the first elliptical portion and the second elliptical portion;
Another aspect of advantageous embodiments of the invention relates to a lighting and/or signaling module, notably for a motor vehicle, comprising at least one unit, the optical element of the at least one unit being formed in a lens.
Optionally, the module comprises a plurality of units in which optical elements are all formed in the lens.
The invention also relates to a light device, notably for lighting and/or signaling, notably for a motor vehicle, comprising at least one module according to the invention. For example, this can be a device for lighting the interior of the vehicle passenger compartment.
According to one embodiment of the invention, the light device is a lighting and/or signaling device for a vehicle and comprises two modules.
In a preferred case, the modules are located at different height levels in a vertical plane.
Optionally, the mean emission directions in at least one module are different from the mean emission directions in at least one other module.
Advantageously in this device, at least one module is configured for its mean emission directions, in the base plane, to be angularly offset relative to the horizontal such that the direction of a ray, from the second light source and passing through the intersection, in the base plane, of the first elliptical portion and of the second elliptical portion is oriented on the horizontal.
The device as a whole can preferentially be incorporated in a motor vehicle front headlight block. It is thus a unitary block.
Another subject of the invention is a vehicle equipped with at least one device of the invention and/or at least one unit and/or one module as indicated above.
Other features, aims and advantages of the present invention will become apparent on reading the following detailed description, and in light of the appended drawings given as nonlimiting examples and in which:
The terms “vertical” and “horizontal” are used in the present description to designate directions, notably beam directions, according to an orientation at right angles to the plane of the horizon for the term “vertical”, and according to an orientation parallel to the plane of the horizon for the term “horizontal”. They should be considered in the conditions of operation of the device in a vehicle. The use of these words does not mean that slight variations about the vertical and horizontal directions are excluded from the invention. For example, an inclination in relation to these directions of the order of + or −10° is considered here to be a minor variation about the two preferred directions.
The term “bottom” or bottom part should generally be understood to mean a part of an element of the invention located, on a vertical plane, below the optical axis. The term “top” or top part should be understood to mean a part of an element of the invention located, on a vertical plane, above the optical axis.
The term “parallel” or the concept of merged axes is understood here notably with the manufacturing or installation tolerances; directions that are substantially parallel or axes that are substantially merged fall within this context.
Furthermore, the relative positions of the different optical elements and of the noteworthy points, such as the light sources, the foci, the diopters and the lens, often expressed in this application for ease of understanding with terms of the type “in alignment” and/or “corresponding” and/or “located on” or “at” should not necessarily be interpreted exactly inasmuch as slight variations may be envisaged or even desirable in order, among other things, to correct the imperfect nature and certain optical aberrations of the optical elements, or to obtain certain additional effects.
The adjective elliptical is employed to define a surface which comprises, in at least one section plane, an ellipse portion profile. It may be an ellipsoidal surface, defined by the rotation of the ellipse portion on one of its axes. The case of
The case represented in the different figures is particularly suited to installation in a front headlight of a motor vehicle. Devices can moreover be installed in a vehicle so as to produce a front left part and a front right part of beam projection toward the front of the vehicle.
Generally, the present invention can use light sources of the light-emitting diode type, more commonly called LEDs. Notably, each of these LEDs can be provided with at least one photoemitter element such as a chip capable of emitting a light of intensity and color adjusted to the lighting and/or signaling function to be produced. For example, a first light source may comprise at least one photoemitter of an LED to provide lighting in amber light for a flashing direction change indication light. Moreover, a second light source may comprise at least one white light photoemitter of an LED to provide a daytime lighting function. One and the same LED can advantageously comprise at least two photoemitters, each configured to at least partly produce a lighting or signaling function differently.
The number of LEDs is not however limiting on the invention, nor on the number of functions likely to be implemented by the overall system of the invention. Moreover, the term light source should be understood here to mean a set of at least one individual source such as an LED chip capable of producing a flux resulting in the generation at the output of the device of the invention of an output flux fulfilling the desired function. Since the LEDs emit substantially in a half-space limited by their plane of installation, the mean emission direction of their photoemitters is typically at right angles to the plane of the LED.
All types of beams can be formed by virtue of the invention, including the different lighting and/or signaling functions indicated at the start of this description. Nevertheless, advantageously, the invention makes it possible to produce, with one and the same lens, all or part of a function of the direction change indication type or all or part of a daytime lighting type function.
It will be understood that the device shown in
This difficulty is overcome according to one aspect of the invention, and notably by the unit whose geometrical construction is illustrated in
The two sources 6, 8 are, moreover, advantageously situated on the input diopter 2, here schematically represented by the rectangular box illustrating the input face of a lens.
Each of the sources 6, 8 is suitable for emitting an input light flux with mean direction corresponding respectively to the directions represented by the references 9 and 10. In the case illustrated, the directions 9, 10 are parallel and extend, in the example, in a horizontal plane. It will be recalled that the invention can be applied to other inclinations and, notably, the directions 9, 10 can be present in a vertical plane, in which case the embodiment described here and illustrated in
According to one embodiment, one of the sources, for example the source 6, makes it possible to form a direction change indication function. Thus, there is represented, instead of the light source 6 in
8. All of the power supply, control and installation means for the sources 6, 8 can thus be pooled within one and the same LED.
Because of the presence of two light sources 6, 8 spaced apart in the direction of the segment 11, the present invention offers the feature of having an optical element suited to the presence of these two sources 6, 8 so as to work, with a single optical element, in good conditions of propagation of the beams and of projection of the output beams despite the offset of the two sources 6, 8.
To this end, the optical element allowing for the input of the light beams from the two sources 6, 8 and the projection of the output beams can have the configuration illustrated in
It should be noted that the invention is not limited to one choice of materials for forming the lens 1. It can be of polymers such as: polycarbonate, polymethyl methacrylate, polypropylene, polybutylene terephthalate or other polymers of the thermosetting type.
According to the invention, the optical element corresponding to the effective lens portion is split for the lighting function from the sources 6, 8 into two portions, each particularly matched to one of the two sources 6, 8.
Thus, a first elliptical portion 12 is constructed corresponding to a surface present on the output diopter 3 and comprising at least one elliptical profile in a plane of intersection with the elliptical portion 12. More particularly, the elliptical portion 12 accepts as focus F1A, the point in
The latter corresponds to a part of the surface of the output diopter 3 particularly suited to the lighting function corresponding to the second light source 8. The construction of the second elliptical portion 13 is preferentially substantially similar to that previously described for the elliptical portion 12. Thus, the second elliptical portion 13 advantageously has a section in the form of an ellipse portion on a vertical plane and/or on a horizontal plane. Moreover, it advantageously allows, as one of its foci F1W, the point where the second light source 8 is situated. Similarly, with respect to the mean emission direction 10 of the second light source 8, the second elliptical portion 13 exhibits an angular clearance in a horizontal plane corresponding to two times the angle schematically represented as “b” in
As indicated previously and can be seen in
It will be noted that, in the construction represented in
The unit according to the invention can thus be formed by the optical element defined as previously and by the pair of sources 6, 8.
In the case represented however, the lens 1 has an additional width on either side of the system of units formed. The benefit of this lateral extension will be explained in more detail with reference to another embodiment which can be seen in
It is in fact advantageous to be able to exploit the presence of a plurality of pairs of sources to apply a projection scanning that best matches the objectives set by the targeted lighting and/or signaling function.
In the case of
It will be noted that
It is also possible to associate units such as those which can be seen in
In the bottom part, under the horizontal plane “xy” passing through F1, the profile of the portion 12 is a part of ellipse defined by a first focus F1 A where the first source 6 is situated and by a second focus F2A situated under the point F2 and on an ellipse axis offset by an angle “60” relative to the direction of the axis y and advantageously passing through the point A.
In the top part, above the horizontal plane “xy” passing through F1, the profile of the portion 13 is a part of ellipse defined by a first focus F1W where the second source 8 is situated and by a second focus F2W situated under the point F2 and on an ellipse axis offset by an angle “74” relative to the direction of the axis y and advantageously passing through the point A.
There is thus obtained a complex section in the plane “xz” with two parts of ellipses, these ellipses being respectively defined by their foci F1A, F2A and FlW and F2W. The two parts of ellipses advantageously meet at the point A.
On the basis of this complex section, the three-dimensional form of the output diopter 3 can be produced by the generation of a cylindrical surface with a generatrix preferentially parallel to the axis “x” and adopting the complex section as the main curve. The result is a cylindrical ply of vertical section with two pieces of ellipses, so that the output diopter 3 comprises two elliptical portions 12, 13, each particularly matched to one of the sources 6,8.
In the case of superposition of modules of the invention each incorporating at least one unit formed according to the embodiment of
This configuration could be employed, with simple corresponding angular modifications, for sources aligned horizontally or in other directions.
Finally, by making relatively little modification to the profile of the output diopter which remains of the type with elliptical section, the optical element can be exploited for dual use from two different light sources 6, 8.
The invention is not limited to the embodiments described previously but extends to all embodiments that conform to its spirit.
While the system, apparatus, process and method herein described constitute preferred embodiments of this invention, it is to be understood that the invention is not limited to this precise system, apparatus, process and method, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
13 51491 | Feb 2013 | FR | national |
Number | Name | Date | Kind |
---|---|---|---|
5499262 | Nakata | Mar 1996 | A |
7204627 | Ishida | Apr 2007 | B2 |
7625102 | Koike et al. | Dec 2009 | B2 |
20060083002 | Koike et al. | Apr 2006 | A1 |
20060250810 | Casenave et al. | Nov 2006 | A1 |
20080253143 | Blandin et al. | Oct 2008 | A1 |
20090091944 | de Lamberterie | Apr 2009 | A1 |
20100084667 | Mcfadden et al. | Apr 2010 | A1 |
20130044503 | Mihara et al. | Feb 2013 | A1 |
Number | Date | Country |
---|---|---|
2525142 | Nov 2012 | EP |
Number | Date | Country | |
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20140233254 A1 | Aug 2014 | US |