Vehicle headlight having a light source

Abstract

A vehicle headlight includes a light source and an adjustable objective. The light source is designed as a field having a plurality of microlight sources. The adjustable objective includes at least three lens groups, at least two of which are designed to be displaceable along the optical axis in order to adjust the focal length and the focal plane.

Claims

1. A vehicle headlight, comprising: a light source having a field comprising a plurality of microlight sources configured to produce a light image; and an adjustable objective comprising at least three lens groups, wherein at least two lens groups of the at least three lens groups are displaceable along an optical axis of the vehicle headlight to adjust a focal length and a focal plane and lenses of a third lens group of the at least three lens groups is not displaceable along the optical axis such that a size of the light image in a plane of illumination and a focusing of the light image in the plane of illumination are adjustable; and wherein the third lens group includes an aperture diaphragm that is not displaceable along the optical axis.

2. The vehicle headlight of claim 1, wherein the microlight sources have microLEDs or micromirror devices.

3. The vehicle headlight of claim 1, wherein the field comprises 30,000 to 1.5 million microlight sources.

4. The vehicle headlight of claim 1, wherein each of the at least three lens groups has at least one optical lens.

5. The vehicle headlight of claim 1, wherein the adjustable objective has at least one aperture diaphragm.

6. The vehicle headlight of claim 1, wherein the adjustable objective additionally contains an iris diaphragm.

7. The vehicle headlight of claim 1, wherein one or more surfaces of one or more optical elements of the adjustable objective are aspherical, and have diffractive structures or an anti-reflection coating.

8. The vehicle headlight of claim 1, wherein materials of individual optical elements of the adjustable objective have different refractive indices.

9. The vehicle headlight of claim 1, further comprising: DC motors, stepper motors, or piezo actuators arranged to displace the at least two lens groups.

10. The vehicle light of claim 1, wherein the third lens group is arranged closer to the light source than the first and second lens groups.

11. The vehicle light of claim 1, wherein the second lens group comprises two convex-concave lenses.

12. The vehicle light of claim 11, wherein the first lens group comprises a plano-convex lens, and the second lens group is arranged closer to the light source than the first lens group.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) The figures show:

(2) FIG. 1 a schematic diagram of a vehicle in a view from above with a projection of a light-dark distribution in various sizes produced by the front headlight of the vehicle in a plane of illumination;

(3) FIG. 2 an exemplary adjustable objective for use in the headlight according to the invention in a first extreme position;

(4) FIG. 3 an exemplary adjustable objective for use in the headlight according to the invention in a second extreme position;

(5) FIG. 4 a schematic depiction of the light cone of the front headlight of a vehicle in the extreme position shown in FIG. 2;

(6) FIG. 5 a schematic depiction of the light cone of the front headlight of a vehicle in the extreme position shown in FIG. 3;

(7) FIG. 6 an exemplary depiction of a simulated full beam distribution in the extreme position depicted in FIG. 2; and

(8) FIG. 7 an exemplary depiction of a simulated full beam distribution in the extreme position depicted in FIG. 3.

DETAILED DESCRIPTION

(9) The depiction of FIG. 1 shows a birds-eye view of a vehicle 1. The possibility of emitting light with different focal lengths and thus with a different beam expansion from the front headlights 4 of the vehicle, which are not visible here, is shown in front of the vehicle 1 as a light image 2 in a plane of illumination designated 3. Here, the solid line three-dimensionally depicts a small magnification 2a, the dashed line a correspondingly larger magnification 2b, of the light image 2 in the plane of illumination 3.

(10) In order now to achieve both the desired size 2a, 2b of the light image 2, and also a high degree of sharpness of the light image in the plane of illumination 3, the vehicle headlight 4 can be constructed in the manner depicted schematically in FIG. 2. The vehicle headlight 4 has, as light source, a field 5 of microlight sources, which are controlled by an intelligent light control system, not shown here, such that they give out a light-dark distribution as light image 2 for projection onto the road and in the plane of illumination 3. As can be seen in the schematic depiction from FIG. 2, this light image 2 is now emitted along an optical axis 6 into the environment. In the process, it passes through three lens assemblies K 1, K 2 and K 3. The lens assembly K 1, which here has for example two lenses 7, 8 and an aperture diaphragm 9, is not displaceable along the optical axis 6 in the exemplary embodiment shown here, and is accordingly fixed. Thus, there is a defined distance to the field 5 of the microlight sources. The lens assembly K 2 likewise consists of two lenses 10, 11 and, as accordingly indicated by the arrow designated 12, is displaceable along the optical axis 6. In the exemplary embodiment of FIG. 2 shown here, it is depicted directly adjacent to the lens group K 3 with a lens 13 and thus in one of its extreme positions, namely the “minimum focal length” extreme position. The emerging light cone designated 14 is correspondingly wide. The lens group K 3 is also displaceable, as indicated by the arrow 15.

(11) The aperture diaphragm can also optionally be designed to be displaceable. An additional iris diaphragm may also likewise be present in the headlight.

(12) In the depiction of FIG. 4, a plan view of the vehicle 1 shows, in this “minimum focal length” position of the lens groups K 1, K 2, K 3 of the front headlight 4, roughly what the schematically depicted light cones 14 look like. They become correspondingly wide very quickly, and are particularly suited to large-area illumination of a plane of illumination 3, not shown in more detail here. The possibility of displacing in particular the lens groups K 2 and K 3 relative to the lens group K 1 and relative to one another makes it possible to precisely adjust, in addition to the desired width of the emerging light cone 14, the sharpness in the plane of illumination 3, such that, in the desired plane of illumination 3, an image of the field 5 of the microlight sources is given both in a variable size and with a desired degree of sharpness, typically the maximum possible.

(13) FIG. 6 shows, in this situation of the “minimum focal length” position, the light distribution using a corresponding simulation, with the light distribution being accordingly brightest in the center and the values decreasing towards the edge, as can be seen from the various scales of grey in the depiction in FIG. 6.

(14) The depiction in FIG. 3 now in turn picks up the same depiction as in FIG. 2. The lens assembly K 2, with its two lenses 10, 11, is now in its other extreme position, namely in the “maximum focal length” position. The emerging light cone 14 is therefore correspondingly narrower and extends to a greater distance, in order to be able to illuminate objects at this greater distance in a targeted manner and to be able to recognize them. FIG. 5 in turn shows, analogously to FIG. 4, the corresponding view of the vehicle 1 with the emerging light cones 14 from above. Particularly by directly comparing the figures, it can be very clearly seen that the schematically depicted emerging light cones 14 are correspondingly narrower here and therefore also provide a higher light intensity even at a greater distance. This can also be seen from the depiction in FIG. 7. Analogously to the depiction in FIG. 6, here again the simulation of the light distribution is depicted. Overall, the illuminated area in the plane of illumination 3 selected by way of example is correspondingly smaller; hence, the light intensity in the center is considerably higher.

(15) Between these two described extreme positions of the maximum focal length in FIGS. 3, 5 and 7, and also the minimum focal length in FIGS. 2, 4 and 6, any desired intermediate values can also be set. This allows the image of the field 5 of the microlight sources in the desired plane of illumination 3 to be displayed at the required size and with the required degree of sharpness, such that a plurality of different illumination subjects can be observed with the vehicle headlight 4 according to the invention, in particular also adaptive illumination in the sense described at the outset, in which objects detected using environment sensors can be illuminated in a targeted manner or even not illuminated, for example in order to prevent dazzling oncoming traffic or dazzling oneself by the very bright illumination of a traffic sign or the like. Furthermore, objects in the environment can be illuminated in a targeted manner, in order to be able to better identify and classify these using environment sensors, for example cameras or the like.

(16) Although the invention has been illustrated and described in detail by way of preferred embodiments, the invention is not limited by the examples disclosed, and other variations can be derived from these by the person skilled in the art without leaving the scope of the invention. It is therefore clear that there is a plurality of possible variations. It is also clear that embodiments stated by way of example are only really examples that are not to be seen as limiting the scope, application possibilities or configuration of the invention in any way. In fact, the preceding description and the description of the figures enable the person skilled in the art to implement the exemplary embodiments in concrete manner, wherein, with the knowledge of the disclosed inventive concept, the person skilled in the art is able to undertake various changes, for example, with regard to the functioning or arrangement of individual elements stated in an exemplary embodiment without leaving the scope of the invention, which is defined by the claims and their legal equivalents, such as further explanations in the description.