Lighting device for a motor vehicle having at least one pixelated light source

Abstract

The invention relates to a motor vehicle lighting device that includes a first module with at least one first pixelated electroluminescent light source where the first module can produce a first pixelated partial high beam (HB1) having a first resolution and a first horizontal angular amplitude; and includes a second module with a second pixelated electroluminescent light source where the second module can produce a second pixelated partial high beam (HB2) having an angular amplitude smaller than that of the first pixelated partial high beam (HB1) and a resolution greater than that of the first pixelated partial high beam (HB2); the pixelated electroluminescent light sources preferably being monolithic.

Claims

1. A motor vehicle lighting device comprising: a first module comprising at least one first pixelated electroluminescent light source, the first module configured to produce a first pixelated partial high beam (HB1) having a first resolution and a first horizontal angular amplitude; a second module comprising a second pixelated electroluminescent light source, the second module configured to produce a second pixelated partial high beam (HB2) having a second angular amplitude smaller than that of the first pixelated partial high beam (HB1) and a second resolution greater than that of the second pixelated partial high beam (HB2); further wherein characterized in that the at least one first pixelated electroluminescent light source and the second pixelated electroluminescent light source have elementary emitters that have an emitting surface of the same size, the first module furthermore comprising a first optical projection system and the second module comprising a second optical projection system, the magnification factor of the second optical projection system being less than that of the first optical projection system such that the resolution of the second pixelated partial high beam (HB2) is greater than that of the first pixelated partial high beam (HB1).

2. The lighting device of claim 1, wherein the first lighting module and the second lighting module are arranged such that, respectively, the first pixelated partial high beam (HB1) and the second pixelated partial high beam (HB2) each have at least 400 pixels.

3. The lighting device of claim 1, wherein the first module is arranged such that each pixel of the first pixelated partial high beam (HB1) has a width or a height less than or equal to 1°.

4. The lighting device of claim 1, wherein the first lighting module is arranged such that the first pixelated partial high beam (HB1) has a vertical amplitude at least equal to 4° and a horizontal amplitude at least equal to 25°.

5. The lighting device of claim 1, wherein the second module is arranged such that each pixel of the second pixelated partial high beam (HB2) has a width or a height less than or equal to 0.3°.

6. The lighting device of claim 1, wherein the second lighting module is arranged such that the second pixelated partial high beam (HB2) has a vertical amplitude at least equal to 2° and at most equal to 6° and a horizontal amplitude at least equal to 8° and at most equal to 20°.

7. The lighting device of claim 1, characterized in that said device is arranged such that the first pixelated partial high beam (HB1) and the second pixelated partial high beam (HB2) at least partially overlap.

8. The lighting device of claim 1, characterized in that the lighting device is arranged such that the first pixelated partial high beam (HB1) and the second pixelated partial high beam (HB2) are juxtaposed.

9. The lighting device of claim 1, characterized in that the second pixelated electroluminescent light source has a number of elementary emitters whose respective emitting surfaces are of a size smaller than that of those of the first pixelated electroluminescent light source; the first module furthermore comprising a first optical projection system and the second module comprising a second optical projection system, the magnification factor of the second optical projection system being equal to or less than that of the first optical projection system such that the resolution of the second pixelated partial high beam (HB2) is greater than that of the first pixelated partial high beam (HB1).

10. The lighting device of claim 1, characterized in that the first pixelated electroluminescent light source or the second pixelated electroluminescent light source has an emitting light surface that is rectangular.

11. A motor vehicle, characterized in that the motor vehicle comprises at least one lighting device of claim 1.

12. The lighting device of claim 1, wherein the first module is arranged such that each pixel of the first pixelated partial high beam (HB1) has a width or a height less than or equal to 0.5°.

13. The lighting device of claim 1, characterized in that the first pixelated electroluminescent light source or the second pixelated electroluminescent light source comprise at least one matrix array of a monolithic matrix array of electroluminescent elements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other features and advantages of the present invention will be better understood with the aid of the description of the examples and of the drawings, in which:

(2) FIG. 1 shows a front view of a lighting device according to one preferred embodiment of the invention;

(3) FIG. 2 shows a plan view of FIG. 1;

(4) FIG. 3 shows a first configuration of light beams projected by a lighting device according to the invention;

(5) FIG. 4 shows another configuration of light beams projected by a lighting device according to the invention.

DETAILED DESCRIPTION

(6) FIGS. 1 and 2 show a lighting device 1 according to one embodiment of the invention. This lighting device comprises a first lighting module 2 capable of projecting a first pixelated partial high beam HB1 and a second lighting module 3 capable of projecting a second pixelated partial high beam HB2. The first and second pixelated beams HB1 and HB2 have been shown in FIGS. 3 and 4, projected onto a screen placed 25 meters from the lighting device 1 and on which have been formed a horizontal axis H-H representing the horizon and a vertical axis V-V, perpendicular to the horizontal axis H-H and intersecting the optical axis X of the lighting device 1.

(7) The first module 2 comprises:

(8) a pixelated electroluminescent light source 21 comprising for example 900 elementary emitters arranged in a matrix array of 20 rows by 45 columns, each of the elementary emitters being able to be activated selectively so as to emit an elementary light beam; and
an optical projection system 22 associated with said light source for projecting each of said elementary light beams in the form of a pixel having a width and a height of 1°.

(9) In the example described, the light source 21 comprises a monolithic matrix array of electroluminescent elements, as described above.

(10) Provision may be made to replace the pixelated electroluminescent light source 21 with any other type of pixelated electroluminescent source described above, such as for example a matrix array of light-emitting diodes.

(11) The set of pixels projected by the first module 2 forms said first pixelated partial high beam HB1. This beam HR has a horizontal amplitude of 25° and a vertical amplitude of 9°. It extends symmetrically on either side of the vertical axis V-V.

(12) The first lighting module comprises at least one pixelated electroluminescent light source 21. It may comprise one, two or three pixelated electroluminescent light sources 21. This makes it possible to obtain a first pixelated partial high beam HB1 of very large horizontal extent.

(13) The first lighting module 2 may comprise elements other than those described above. These elements will not be described in the context of the present invention since they do not interact functionally with the arrangements according to the invention.

(14) The second lighting module 3 is structurally similar to the first lighting module 2.

(15) The second module 3 comprises:

(16) a pixelated electroluminescent light source 31 comprising for example 900 elementary emitters arranged in a matrix array of 20 rows by 45 columns, each of the elementary emitters being able to be activated selectively so as to emit an elementary light beam; and
an optical projection system 32 associated with said light source for projecting each of said elementary light beams in the form of a pixel having a width and a height of 0.3°.

(17) The lighting device comprises an additional module 4, intended to produce a complementary low beam LB.

(18) The additional module 4 comprises:

(19) a matrix array 41 of elementary emitters comprising 9 light-emitting diodes able to be activated selectively and arranged along a row, each diode being able to emit an elementary light beam;

(20) a plurality 42 of primary optical elements arranged in front of the matrix array 31 for collecting, formatting and guiding the elementary light beams originating from each of the light-emitting diodes; and

(21) projection projection optical system 43 arranged in front of the primary optical elements for projecting each of said elementary light beams originating from the primary optical elements in the form of a pixel having a width of 3° and a length of 5°.

(22) Reference may in particular be made to document FR3056692, which describes the operating principle of such a module.

(23) The second pixelated beam thus forms a pixelated low beam.

(24) Finally, the lighting device 1 comprises a control unit 5 each able to selectively control the light intensity of each of the pixels of the first and second beams HB1 and HB2 on the basis of control instructions that it receives, for example by switching on and by selectively switching off the elementary emitters of the light sources 21 and 31 or else by varying, in an increasing or decreasing manner, the electric power supplied to each of these elementary emitters.

(25) According to a first configuration of the invention, as shown in FIG. 3, the first and second lighting modules 2 and 3 are arranged such that the first and second beams HB1 and HB2 at least partially overlap. In this case, the second beam HB2 is contained in the first beam HB1.

(26) According to another configuration of the invention, as shown in FIG. 4, the first and second lighting modules 2 and 3 are arranged such that the first and second beams HB1 and HB2 are adjacent. In this case, the second beam HB2 is framed within the first beam HB1, which is broken down into a plurality of sub-areas. Each of these sub-areas may be generated by a dedicated pixelated electroluminescent light source 21. In the example illustrated, there are three pixelated light sources in order to cover the field and the shape of the pixelated high beam HB1.