AT518557A1 - Lighting unit for a motor vehicle headlight for generating a light beam with cut-off line - Google Patents

Abstract

The illumination unit (100) has at least one light source (1), at least one collimator (2), and an exit lens (3) with a light source (100) for a motor vehicle headlight Outer surface (3a) and a focal line region (4), which is arranged between the at least one collimator (2) and the exit lens (3), and wherein the collimator (2) is designed and arranged such that from the at least one collimator (2) emergent light beams (S2) in the vertical direction directly to the focal line (FL) or in the focal line area (4) are bundled.

Description

Lighting unit for a motor vehicle headlight for generating a

Light bundle with light-dark border

The invention relates to a lighting unit for a motor vehicle headlight for generating a light beam with a light-dark boundary, the lighting unit comprising: at least one light source, at least one collimator, one light source for each collimator, one exit lens with an outer surface, a focal line region which is arranged between the at least one collimator and the exit lens, wherein the at least one collimator aligns the light beams fed into the collimator by the light source assigned to it into a light bundle of light beams, and light beams of the light bundle emerging from the at least one collimator reach the focal line area or into a focal line lying in the focal line area, and wherein the light rays emerging from the at least one collimator are deflected by the exit lens at least in the vertical direction such that the out of the exit lens passing light beams form a light distribution with a light-dark boundary, wherein the light-dark boundary as an image of the focal line or the focal line area results through the exit lens, and wherein the at least one collimator, the exit lens and the focal line area in one piece from a translucent Body are formed, and wherein on at least one boundary surface of the at least one collimator, the light beams propagating in the light-transmissive body are totally reflected.

Furthermore, the invention relates to a lighting device with at least two such lighting units, wherein preferably the light-transmissive body of the lighting units are horizontally adjacent to each other and / or one above the other, and in particular the light-transmitting body of the at least two lighting units are connected to each other, preferably integrally formed.

Finally, the invention also relates to a motor vehicle headlight which has at least one such lighting unit or at least one such lighting device.

A lighting unit in the context of the present invention may be used in a motor vehicle headlight, e.g. be used for the realization of a part of a low-beam distribution, in particular the apron light distribution of a low-beam light distribution or for the realization of fog light.

Current design trends often require headlamps which have narrow and horizontally extending, slit-shaped light exit openings in the vertical direction. An illumination unit mentioned in the introduction can be realized in the region of the light exit surface with a low overall height, which in certain embodiments can only be up to 10 mm or up to 15 mm, resulting in a slot-shaped light exit surface extending in the horizontal direction.

In the typical lighting units disclosed in the prior art, e.g. one of which is described in DE 60 2006 000 180 T2, the light fed into the light-conducting body is deflected by a totally reflecting reflector formed in the light-guiding body onto the exit lens.

It is an object of the invention to be able to realize a lighting unit with even lower overall height.

This object is achieved with an illumination unit mentioned in the introduction in that, according to the invention, the at least one collimator is designed and arranged such that light beams emerging from the at least one collimator are focused in the vertical direction onto the focal line or into the focal line area.

It has been found that with appropriate design of the collimator on a reflector and corresponding to a deflection of the emerging from the collimator

Light beams can be dispensed with, whereby the height of the optical fiber optic body and thus that of the lighting unit can be significantly reduced.

In the abovementioned DE 60 2006 000 180 T2 it is provided that the light exit surface, i. the outer surface of the exit lens is smooth. It has been found that often the achievable light image or the achievable light distribution in the horizontal direction is not sufficiently wide and the illumination of the street has disturbing inhomogeneities.

The optic body is preferably a solid body.

In the present lighting unit, it is preferably provided that the outer surface of the exit lens is formed by a groove-shaped structure in a smooth base surface, wherein the grooves forming the groove-shaped structure extend in a substantially vertical direction, and preferably each two in the horizontal direction adjacent grooves through a, in particular substantially vertically extending, elevation, which preferably extends over the entire vertical extension of the grooves, are separated. The smooth base surface is preferably C0-continuous and in particular has no horizontally extending edges.

As described above, the necessary width for the desired light image, in particular not for an apron light distribution of a low-beam light distribution, can often not be achieved with a smooth outer surface of the exit lens. In particular, given a waiver of a deflecting reflector as provided in the present invention, this can be problematic. The proposed structure on the outer surface of the exit lens, a horizontal blurring of the exiting light beams is achieved, which can achieve the desired width of the light distribution.

It is preferably provided that the at least one boundary surface of the at least one collimator is designed in such a way that the light totally reflected on this at least one boundary surface of the light source associated with the collimator is radiated in a convergent manner in the vertical direction so that it focuses on the focal line or in the focal line region becomes.

In particular, it may be provided that a central coupling-in area of the at least one collimator in the form of a lens, in particular in the form of a free-form lens, is designed in such a way that light coupled into the collimator via the central coupling area is radiated convergently in the vertical direction, so that it is focused on the focal line or in the focal line area.

Furthermore, it can advantageously be provided that all light beams emerging from the collimator are focused in the vertical direction onto the focal line or into the focal line area.

It can be provided that the at least one collimator, in particular at least one boundary surface and / or a central coupling region, of the at least one collimator is or are designed such that in the horizontal direction the light beams emerging from the at least one collimator are parallel to one another run.

In this way, an improved homogeneity of the light rays in the area at the exit lens can be achieved.

It can also be provided that the at least one collimator, in particular at least one boundary surface and / or a central coupling region, is or are designed such that in the horizontal direction the light beams emerging from the at least one collimator converge, preferably in such a way that that the light beams cross approximately in the area of the exit lens, in particular approximately in the area of the outer surface of the exit lens.

In this way, the width of the light distribution can be increased when the width of the light-conducting (optical) body is opposite.

The lens region is generally a free-form lens, with mostly positive refractive power, but which is not rotationally symmetrical. The so-called east / west / north / south curves of the outer surface of the collimator are preferably also free-form curves. For a focusing (converging beams), these curves, shown in simplified form, a sequence in approximately / elliptical 'curve sections, for a Parallelrichten arise, in simplified terms, approximately' parabolic 'curves. Do you have this

Curves, for example, the above-mentioned east / west / north / south curves (or other curves, or a different number of curves) determined, they are connected to a preferably at least Gl-steady surface, for example, such that at each constant Z (parallel planes normal to the optical axis) the two associated curve points lie on an ellipse. An appropriate choice of the tangent directions at these connection points produces a closed contour curve which satisfies the GI condition.

It is preferably provided that the illumination unit has exactly one collimator with an associated light source. A motor vehicle headlamp consists for example of eight to fifteen lighting units according to the invention.

It is particularly preferred if the at least one collimator and the exit lens are arranged relative to one another such that light emerging from the at least one collimator passes directly to the exit lens, in particular without prior deflection and / or reflection.

Preferably, the light source with its collimator to be arranged at one end of the translucent optical body, at the other, opposite end is the exit lens, with only the focal line area with the focal line therebetween; a deflecting reflector is omitted, so that the optical body can be built much lower.

For example, it is provided that a light exit surface of the at least one collimator is substantially normal to an optical axis of the exit lens.

Each collimator has a light exit surface which is planar, with which the collimator merges into the optical body of preferably identical material in one piece, so that this light exit surface has no optical effect.

In particular, it may be provided that the at least one light source is lower than the focal line area or the focal line, or higher than the focal line area or the focal line, or at the same height as the focal line area or the focal line.

It can be provided that on the underside of the optical body two optical body outer surfaces running towards each other form a body edge, which lies in the region of the focal line or in the focal line region or forms the focal line region. By selecting the vertical normal distance of the body edge from the optical axis or the focal line, the magnitude of the lowering of the dimmed light distribution can be determined.

In this case, it may be expedient that the optical body outer surface facing the at least one collimator is embodied on its outer side at least partially, preferably in its entire region, to absorb light which propagates in the optical body and impinges on this optical body outer surface.

For example, the corresponding optic body outer surface may be covered, such as with a black cover member, e.g. a diaphragm, or a corresponding coating, etc. In this way it can be prevented that light can escape uncontrollably from the optical body or is reflected back into the optical body and then spreads there uncontrolled.

As described above, it is preferably provided in the present lighting unit that the outer surface of the exit lens is formed by a groove-shaped structure in a smooth base surface. In this context, it may preferably be provided that the first base-section curves resulting from cutting the smooth base surface with first, non-vertical sectional planes are rectilinear, and the first outer-surface sectional curves resulting from cutting the outer surface with these first section planes sinusoidal course.

In particular, it can be provided that the first outer surface sectional curves in the first sectional planes, with respect to the basic sectional curve of the respective first sectional plane, are proportional to sinN (k * x), with N = 1, 2, 3, ... ., where x denotes the coordinate along the respective base sectional curve and k denotes a constant.

It can be provided that the zero crossings of the sinusoidal first outer surface section curves lie on the first base sectional curves.

It thus holds that the course is proportional to sinN (k * x) + c with c = 0.

In particular, it can be provided that the value for the constant k is identical for all first outer surface sectional curves.

Furthermore, it may be expedient if the second base-sectional curves resulting from a cutting of the smooth base surface with second, vertical cutting planes, which run parallel to an optical axis of the exit lens, are curved, in particular outwardly curved, preferably the second Basic-cut curves are steady.

In this context, it may be expedient if the second outer surface sectional curves resulting from a cutting of the outer surface with defined second cutting planes connect points of the outer surface with a maximum distance to the base surface.

In particular, it is advantageous if, when proceeding along the second basic sectional curve in the defined sectional planes, the normal distance to the second outer surface sectional curve is a function A (s) of a parameter s, which indicates the position on the second basic sectional curve ,

The second cutting planes are vertical planes parallel to the optical axis of the translucent body, i. the exit lens of the optical body.

The optical axis means the optical axis of the optical body, in particular the center line of the optical body defined with respect to the apex of the exit lens.

At a considered point on the base surface, the first cutting plane results as follows: the first cutting plane in the point under consideration is a plane normal to the tangent plane to the base plane, this plane, i. the first cutting plane, still normal to the second cutting plane, in which the point is located, is. The second cutting plane, as stated above, is a vertical one

Section plane through the smooth base surface, which is parallel to the optical axis (or through this optical axis), and in which the considered point lies.

In a base surface which is curved only in the vertical direction but normal in the horizontal direction to the optical axis but rectilinear, although the angle with respect to the optical axis changes between adjacent first cutting planes, in the horizontal direction normal to the optical axis, on the other hand all cutting planes straight and "parallel" to each other.

In this case, it is advantageously provided that the normal distance A (s) increases continuously as it progresses along the second base-section curve, whereby preferably the normal distance at a lower edge of the base surface is smaller than at an upper edge of the base surface, whereby the normal distance A (s), for example, according to the relationship A (s) = Ao * (K - s), where s [0,1], where s = 0 denotes the position at the top and s = 1 denotes the position at the bottom, and K = 1 or K> 1, yields. Thus, for K = 1, Ao is the normal distance at an upper or lower, preferably the upper edge (s = 0) of the base surface (BF), at the lower edge (s = 1), A (l) = 0. For a value K> 1 holds that at the upper edge (s = 0) the normal distance is A (0) = K * Ao, and at the lower edge the normal distance A (l) = Ao * (K - 1)> 0.

In the case with K> 1, in part, a better optical efficiency has been shown than in the case K = 1.

Thus, in this embodiment, there are vertical second cutting planes, in each of which the superimposed "zero crossings", ie those regions where the outer surface and the base surface coincide with each other by corresponding second outer surface sectional curves, in this case with the second base-sectional curves coincide, are connected.

Likewise, there are second cutting planes in which the second outer surface intersection curves connect the negative normal distances / amplitudes together. For a clear description, however, it is sufficient to specify the second outer surface section curves for the "positive" normal distances / amplitudes, the other relationships result from the sinusoidal curve in the first sectional planes.

For example, it can be provided that the outer surface of the exit lens is curved in the vertical direction outwards, and preferably in the horizontal direction is rectilinear, and is formed for example by a cylindrical surface with a straight cross-section along an outwardly convex curve. An example of such an outwardly convex curve is called an aspheric lens contour.

For example, it is a free-form lens, which is curved in the vertical direction to the outside and not curved in the horizontal direction.

The at least one light source preferably comprises one or more semiconductor-based light-emitting elements, e.g. a light emitting diode or a plurality of light emitting diodes, and / or e.g. at least one laser light source comprising at least one laser diode having at least one conversion layer.

Generally, a light source, e.g. one of the light sources described above, used, which has a flat light-emitting surface or whose light-emitting surfaces lie in a plane. Preferably, it is then further provided that the normal to this plane light-emitting surface or this plane (the light-emitting surfaces) is normal to the light exit surface of the collimator associated with the light source and / or runs parallel to the optical axis of the exit lens. Also conceivable tilt angle between the normal direction and the optical axis, in particular tilt angle of max. 10 °. This can e.g. be advantageous in the combination of several lighting units next to each other, where the exit lens is inclined to the direction of propagation (Fahrzeugstrak), so that the LEDs can still be mounted on a common plate.

In one embodiment of the invention, a sinusoidal groove optic is provided in summary, with the sine function normal to the lens surface, i. the smooth base surface of the exit lens is. The period preferably remains unchanged, while preferably the groove depth (amplitude), in particular linear, e.g. as described above from a certain initial value Ao or Ao * K (with this value, the

Width of the light distribution can be adjusted) at the upper edge of the light exit surface to a value of zero or Ao * (K - 1) at the lower edge of the lens changed.

This can be achieved that widened the distribution of light as desired, and surprisingly, it has also revealed that the light-dark boundary to the outside, even with a rectilinear focal line of the translucent body, does not bends.

In the following the invention is discussed in more detail with reference to the drawing. In this shows

1 shows the essential components of a lighting unit according to the invention for a motor vehicle headlight in a first perspective view,

1a shows the illumination unit from FIG. 1 in another perspective view, FIG.

2 is a plan view of a lighting unit of Figure 1,

2a is a vertical section through the illumination unit of Figure 1,

2b shows a detail of the focal line area (position of the body edge to the optical axis with offset)

3 shows the beam path in the optical body of the illumination unit in the vertical direction in a plane containing the optical axis,

3a shows a first beam path in the optical body of the illumination unit in the horizontal direction in a plane containing the optical axis,

3b shows a second beam path in the optical body of the illumination unit in the horizontal direction in a plane which contains the optical axis,

FIG. 3c shows a third ray path in the optical body of the illumination unit in the horizontal direction in a plane which contains the optical axis, FIG.

4 shows a perspective view of a front part of a lighting unit with a light-transmissive body whose exit lens has no groove structure,

4a shows a light distribution generated by a lighting unit from FIG. 4,

5 shows a perspective view of a front part of a lighting unit with a light-transmissive body, whose exit lens has a groove structure, and

5a shows the light distribution generated with this,

6 shows in a vertical section an enlarged section of the light-transmissive body of FIG. 5 between its focal line and the light exit surface;

7 shows the course of the light exit surface of the exit lens of the translucent body in a section along an exemplary first sectional plane SEI from FIG. 6, FIG.

8 again shows the vertical section from FIG. 6 with exemplary sectional areas A-A, B-B, C-C and D-D,

9a-9d show the course of the light exit surface of the exit lens of the translucent body in the various sections A-A, B-B, C-C and D-D in accordance with FIG. 8 for K = 1, and FIG

10a-10d the course of the light exit surface of the exit lens of the light-permeable body in the various sections A-A, B-B, C-C and D-D according to FIG. 8 for K> 1, FIG.

11 shows a lighting device comprising four lighting units according to the invention, and

12 is a front view of a lighting device with six lighting units.

In the context of this description, the terms "top", "bottom", "horizontal", "vertical" are to be understood as indications of the orientation when the unit is in normal

In use position after it has been installed in a vehicle-mounted lighting device.

Figures 1, la, 2 and 2a show a lighting unit 100 according to the invention for a motor vehicle headlight for generating a light beam with cut-off. The illumination unit comprises a light source 1, a collimator 2, an exit lens 3 with an outer surface 3a and a focal line region 4, which is arranged between the collimator 2 and the exit lens 3.

Collimator 2, exit lens 3 and focal line region 4 are formed from a translucent, one-piece body 101 ("optical body"), wherein the optical body 101 is preferably - in general, ie not limited to the present embodiment - is a solid body, ie a Body having no through holes or opening inclusions.

The translucent material of which the body 101 is formed preferably has a refractive index greater than that of air. The material contains e.g. PMMA (polymethyl methacrylate) or PC (polycarbonate) and is particularly preferably formed therefrom. The body 101 may also be made of inorganic glass material.

In the example shown, the optic body 1 has two optical body outer surfaces 1 a, 1 b running towards each other on its underside, which converge into a body edge 4 '. This body edge 4 'is located in the region of the focal line FL of the exit lens or focal line region 4. It may be expedient that the collimator 2 facing optic body outer surface la on its outside at least partially, preferably in their entire area, for themselves in the Optic body 1 reproducing, on this optical body outer surface la incident light, light absorbing is formed.

For example, the corresponding optical body outer surface 1a may be covered, such as with a black cover member, e.g. a diaphragm, or a corresponding coating, etc. In this way it can be prevented that light can escape uncontrollably from the optical body or is reflected back into the optical body and then spreads there uncontrolled.

The light source 1 comprises one or more semiconductor-based light-emitting elements, e.g. a light emitting diode or a plurality of light emitting diodes, and / or e.g. at least one laser light source comprising at least one laser diode with at least one conversion layer. In the example shown, the light source 1 lies deeper than the focal line region 4 or the focal line FL.

The collimator 2 is formed and arranged such that at least parts or all of the light source S1 fed into the collimator 2 from the collimator 2 exit from the collimator 2 (light beams S2) in a vertical direction toward the focal line FL or the focal line area 4 be bundled, as shown in Figure 3.

For this purpose, it is preferably provided that an outer boundary surface 2a of the collimator 2 is formed in such a way that the total-reflected light on this boundary surface 2a is radiated convergently in the vertical direction so that it is focused onto the focal line FL or into the focal line region 4.

The collimator 2 has a coupling-in recess 2 ', which has lateral coupling-in surface 2c, via which light S1 coupled in by the light source 1 is emitted onto the limiting surface 2a.

Furthermore, the coupling-in recess 2 'has a central coupling-in area 2b, which is preferably designed in the form of a lens, in particular in the form of a free-form lens 2b', such that light S1, which is coupled into the collimator 2 via the central coupling region 2b is radiated convergent (light rays S2) so that it is focused on the focal line FL or in the focal line area 4.

The light beams S2 emerging from the collimator 2 will finally be deflected by the exit lens 3 at least in the vertical direction V such that the light beams S3 emerging from the exit lens 3 form a light distribution with a light-dark boundary, whereby the light-dark Boundary as an image of the focal line FL and the focal line area 4 through the exit lens 3 results.

As can be seen in FIG. 2a, in the example shown there, the focal line FL, which lies in the optical axis Z of the exit lens, lies in the vertical direction approximately at the level of the body edge 4 'or slightly below it. FIG. 2 b shows a further possible embodiment in which the body edge 4 'lies above the focal line FL of the exit lens 3. About such a height difference in the vertical direction, the extent of the reduction of the cut-off in the light image can be adjusted.

3a shows an example of how the light beams S2 "emerging" from the collimator 2 extend in the horizontal direction. <br/> According to FIG. 3a, the collimator 2 is designed in such a way, in particular its limiting surface 2a and the central coupling-in region 2b in the form of a free-form lens 2b 'that in the horizontal direction, the light rays exiting from the at least one collimator 2 converge, preferably such that the light beams cross approximately in the region of the exit lens 3, in particular approximately in the region of the outer surface 3a of the exit lens 3, or in front of the exit lens It can also be provided that a part of the light beams, in particular those from the central area 2b, already cross over in the area of the focal line FL or in front of the focal line FL In this way, the width of the light-conducting (optical) body can be reduced and increase the width of the light distribution.

3 b shows an example of how the light beams S 2 "emerging" from the collimator 2 run in the horizontal direction According to FIG. 3 b, the collimator 2 is designed in such a way, in particular its boundary surface 2 a and the central coupling-in area 2 b in the form of a free-form lens 2 b 'that the light rays S2 "emerging" from the collimator run parallel to one another in the horizontal direction, and preferably also parallel to the optical axis Z. In this way, an improved homogeneity of the light beams in the area at the exit lens and the light distribution can be achieved.

Finally, FIG. 3c also shows a mixed embodiment in which the light beams passing through the coupling-in region 2b of the collimator 2 converge, so that they cross over in front of the exit lens, in particular already in front of the focal line in the horizontal direction, while those beyond the central coupling region the area 2c emerging light beams in the horizontal direction parallel to each other, in particular parallel to the optical axis Z extend.

As can be seen in FIGS. 1, 1a and 2, 2a and 3, 3a, 3b, the collimator 2 and the exit lens 3 are arranged relative to each other such that light S2 exiting from the collimator 2 directly, in particular without prior deflection and / or Reflection by a reflector, comes to the exit lens 3.

Specifically, the light source 1 is located with its associated collimator 2 at one end of the translucent optical body 101, at the other, opposite end is the exit lens 3, between them only the focal line region 4 with the focal line FL; on a deflecting reflector is omitted, so that the optical body 101 can be built much lower.

For example, it is provided that a light exit surface 2d of the collimator 2 is substantially normal to an optical axis Z of the exit lens 3. The collimator 2 has a light exit surface 2d, which is planar, with which the collimator 2 integrally merges into the remainder of the optical body of preferably identical material, so that this light exit surface 2d has no optical effect.

The focal line FL lies in the focal line region 4 of the body 101 and preferably coincides substantially with the focal line of the exit lens 3.

The focal line region 4 is arranged around an edge in the body 101. By mapping the edge 4, which is a curved line, in particular with a small curvature or particularly preferably a straight line, the HD line is formed.

The light possibly exiting below the edge 4 over the surface 1a is shaded / absorbed by absorbing the surface 1a underlying the edge 4, e.g. through a blind or a dark, e.g. black or brown coating on its outside, etc., is shaded to avoid false / stray light

The outer surface 3a of the exit lens 3 of the body 101 is curved outwards in the vertical direction, preferably in such a way that in a central region the exit surface in the light exit direction is further forward than its upper and lower edge regions. In the horizontal direction, the exit lens is preferably rectilinear and is formed, for example, by a straight-sided cylindrical surface along an outwardly convex curve, or by a free-form lens curved outwardly in a vertical direction and not curved in a horizontal direction.

FIG. 4 shows the front part of a lighting unit 101 ', from which a lighting unit 101 according to the invention can be derived, as already indicated in principle in the preceding figures. The illumination unit 101 'partially shown in FIG. 4 has an exit lens 3' with a smooth exit surface 3a '.

Figure 4a shows a light distribution with a cut-off, e.g. a low beam distribution or a part, e.g. the apron of a low beam distribution. Such a light distribution has a certain width, as indicated in FIG. 4a.

Starting from such a lighting unit 101 ', the front part of an illumination unit 101 already described with reference to FIGS. 1, 1a, 2, 2a and 3, 3a, 3b is shown in FIG.

The difference from the embodiment according to FIG. 4 is that in the illumination unit 101 of FIG. 5 the outer surface 3a of the exit lens 3 consists of a smooth base surface BF (corresponding to the exit surface 3a 'of FIG. 4) which is provided with a groove-shaped structure, wherein the groove-shaped structure forming grooves 3b in the vertical direction, ie from top to bottom, run. Concretely, the outer surface 3a of the exit lens 3 is formed by a groove-shaped structure in a smooth base surface BF, wherein the grooves 3b forming the groove-shaped structure extend in a substantially vertical direction, and preferably two in each case horizontally adjacent grooves 3b by one, in particular substantially vertically extending elevation, which preferably extends over the entire vertical extension of the grooves 3b, are separated.

As described above, with a smooth outer surface BF, 3a 'of the exit lens, it is often not possible to achieve the necessary width for the desired light image, in particular not for an apron light distribution of a low beam distribution. A structure on the outer surface of the exit lens achieves a horizontal blurring of the exiting light beams, whereby the desired width of the light distribution can be achieved, as shown schematically in FIG. 5a. In addition, the quality of the light distribution is significantly improved, since the impression of homogeneity is improved by the structure on the outer surface of the exit lens.

FIGS. 6-8, 9a-9d, 10a-10d show below a preferred embodiment of this groove structure according to the invention.

Figure 6 and Figure 8 show vertical sections through the body 101, and in each case an enlarged section of the light-transmissive body between its focal line FL and the light exit surface 3a.

FIG. 6 shows a second vertical section which contains a considered point P on the base surface BF, FIG. 8 shows a second vertical section SE2 in which four points PA, PB, PC and PD considered as examples lie.

If one cuts the smooth base surface BF with first, non-vertical cutting planes SEI (these cutting planes SEI are discussed in more detail below), for example at the point P (FIG. 6) or corresponding to the sections AA, BB, CC, DD (FIG. 8), This results in first basic sectional curves BSK1, which run in a straight line, wherein the first outer surface sectional curves SKI (which correspond to the course of the lens outer surface in these sectional planes SEI) when the outer surface 3a intersects with these first sectional planes SEI have a sinusoidal profile exhibit.

The smooth base surface is an intellectual construct in relation to which the outer surface actually realized is described. The first non-vertical cutting planes SEI are a multiplicity of such non-vertical cutting planes, which are still defined precisely below.

In the preferred example shown, the first outer surface sectional curves SKI in the first sectional planes SEI, with respect to the basic sectional curve BSK1 of the respective first sectional plane SEI, are proportional to sinN (k * x), with N = 1, 2, 3 , .... (in the example shown N = 1), where x denotes the coordinate along the respective base-section curve BSK1 and k is a constant.

It can be provided that the zero crossings of the sinusoidal first outer surface sectional curves SKI lie on the first basic sectional curves BSK1. It thus holds that the course is proportional to sinN (k * x) + c with c = 0.

FIG. 7 shows such an exemplary first sectional plane SEI in which the point P lies, which is normal to the tangential plane TE in the point P (FIG. 6), for a general illustration of the relationships. In this section, the lens outer surface is shown with respect to a first base section curve BSK1. The base intersection curve BSK1 is a line with the parameter x along this line BSK1. The lens outer contour in this section is a first outer surface sectional curve SKI, which in this example is proportional to sin (k * x). Depending on a position s (for the parameter s see the discussion below) corresponding to the point P, i. s = sp in the section according to FIG. 6, the maximum amplitude is determined by A (sp), as shown in FIG. The determination of the amplitude will be discussed in more detail below.

FIG. 8 shows a section along a second, vertical sectional plane SE2 parallel to the optical axis Z, with the four exemplary points PA, PB, PC and PD.

The first sectional planes SEI are shown in these four points, and the corresponding curves of the resulting second outer surface sectional curves SK2 for the four selected sectional planes SEI (corresponding to sections A-A, B-B, C-C and D-D) are shown in FIGS. 9a-9d. For the sake of clarity, twice the amplitude, ie the distance between maximum and minimum deflection, is shown in the sections.

In turn, in correspondence with FIG. 6, the sinusoidal profile of the second outer surface sectional curve SK2 is recognizable, k applies for k = 2 * π / Τ, with the period length T. Preferably, it is provided that the value for the constant k is identical for all first outer surface sectional curves SEI.

In general, regardless of the embodiment shown, typical values for the period length T [mm] are in a range up to 2.50 mm, preferably up to 2.00 mm. In particular, preferred values are between 0.10 mm to 2.00 mm, for example between 0.25 mm and 0.75 mm.

Preferred values for the maximum amplitude Ao [μιη], regardless of the embodiment shown, are in a range from 25 μm to 350 μm, a typical value being 50 μm.

As a favorable value range for the size ratio Ao to T, for example, 0.075 <(Ao / T) <0.250 has resulted.

The above information applies to the case K = 1 (for the parameter K see the comments above in the introduction), for the case K> 1, the analog considerations apply, in which case in the two preceding paragraphs Ao by Ao * K to replace is.

FIG. 8 further shows (as well as FIG. 6) that the second base-section curves BSK2 resulting from cutting the smooth base surface BF with the second vertical sectional planes SE2, which run parallel to an optical axis Z of the exit lens 3, are curved, in particular curved to the outside, are formed, wherein preferably the second base-sectional curves BSK2 are continuous.

In this context, it is provided that the second outer surface sectional curves SK2 resulting from a cutting of the outer surface 3a with defined second sectional planes SE2 connect points of the outer surface 3a with a maximum distance to the base surface BF. The second planes SE are thus preferably vertical sectional planes parallel to the optical axis Z, for which the amount of sinN (k * x) = 1. These second planes are sufficient for the definition of the outer lens surface, the regions between these vertical planes are defined by the sine function described above.

With a progression along the second basic intersection curves BSK2 in the defined intersecting planes SE2, the normal distance of the second outer surface intersection curve SK2 to the second basic intersection curve BSK2 can be considered as a function A (s) of a parameter s representing the position on the second basis -Section curve BSK2 indicates represent.

For the time being, once again coming back to the first cutting planes, it should be said that in a considered point P (FIG. 6), PA, PB, PC, PD (FIG. 8) on the base surface BF the first cutting plane SEI results as follows: the first sectional plane SEI in the considered point P, PA,... is a plane normal to the tangential plane TE to the base surface BF, this plane (= sectional plane SEI) still remaining normal to the second sectional plane SE2, in which the point P is, stands. As already explained above, the second cutting plane is a vertical sectional plane through the smooth base surface BF, which runs parallel to the optical axis Z (or through this optical axis Z) and in which the considered point P lies. The first sectional planes SEI enclose an angle of 90 ° with the second basic sectional curve BSK2.

In a base surface which is curved only in the vertical direction but normal in the horizontal direction to the optical axis Z but straight, between adjacent first cutting planes SEI, although the angle with respect to the optical axis Z, in the horizontal direction normal to the optical changes Axis Z, however, all the cutting planes run straight and "parallel" to each other.

Returning now to the second, vertical sectional planes SE2 and to the course of the outer surface sectional curve SK2, the function A (s) follows, for example, the relationship A (s) = Ao * (1-s), where s [0,1] where Ao is the normal distance at the upper edge of the base surface BF.

Here, s = 0 is the position at the upper edge of the base surface, where A (0) = Ao, at the lower edge A (l) = 0. The parameter thus represents a normalized arc length along the curve BSK2. For the parameter s applies in the four points according to FIG. 9:

Thus, in this embodiment, there are vertical second cutting planes, in each of which the superimposed "zero crossings", ie those regions where the outer surface and the base surface coincide with each other by corresponding second outer surface sectional curves, in this case with the second base-sectional curves coincide, are connected.

Likewise, there are second cutting planes in which the second outer surface intersection curves connect the negative normal distances / amplitudes together. For a clear description, however, it is sufficient to specify the second outer surface section curves for the "positive" normal distances / amplitudes, the other relationships result from the sinusoidal curve in the first sectional planes.

The above-described relation A (s) = Ao * (l-s) is a special case of the more general case A (s) = Ao * (K-s), where K = 1. It has been found that partly the optical Efficiency is better for K> 1 than for K = 1. A typical value for parameter K is in the range of 1.2 to 1.45, preferably about 1.33.

In this case shown in FIGS. 10a-10d

In summary, the contour of the outer surface 3a can be represented by an "imaginary" base surface BF

In one embodiment of the invention, a sinusoidal groove optic is provided in summary, with the sine function normal to the lens surface, i. the smooth base surface of the exit lens is. The period preferably remains unchanged, while preferably the groove depth (amplitude), in particular linear, from a certain initial value Ao (with this value, the width of the light distribution can be set) at the upper edge of the light exit surface to a value of zero at the lower edge of the lens changed. This can be achieved that widened the distribution of light as desired, and surprisingly, it has also revealed that the light-dark boundary to the outside, even with a rectilinear focal line of the translucent body, does not bends.

FIG. 11 shows a lighting device comprising four lighting units 100 according to the invention, which have a construction as described above. The optic bodies of the individual illumination units 100, like the light sources 1, are arranged horizontally next to one another. Preferably, the optical bodies form a common one-piece optical body 1101. In the example shown, the exit surfaces of the exit lenses 3 form a continuous surface, which represent a straight line in horizontal sections.

11 shows a further such a lighting device in a front view, which in principle has a similar construction to that of FIG. 11 (eg with one-piece optical body, but the individual optical bodies can also be separate), the lighting device having six illumination units and thus six exit lenses (FIG. again in one piece or separately).

Because of the feeding in of the light in the emission direction (= direction of travel) according to the invention, a plurality of lighting units according to the invention can be arranged next to each other in modules and / or vertically offset from one another, the optical axes of the individual lighting units following a DK. This is possible because the exit lenses can be cut easily and corresponding design requirements can be met. In addition, the width of the individual illumination unit can be reduced and / or an adaptation to a desired vehicle headlight sweep can be achieved by an oblique trimming of the exit lenses (or of the total exit lens, ie the sum of all individual exit lenses 3).

Claims (26)

claims 1. Lighting unit for a motor vehicle headlight for generating a light beam with cut-off, wherein the lighting unit (100) comprises: - at least one light source (1), - at least one collimator (2), - one light source (1) for each Collimator (2), - an exit lens (3) having an outer surface (3a), - a focal line region (4) which is arranged between the at least one collimator (2) and the exit lens (3), wherein the at least one collimator (2 ) aligning the light beams (S1) fed into the collimator (2) from the light source (1) associated therewith to form a light bundle of light beams (S2), and light beams (S2) of the light bundle emerging from the at least one collimator (2) Firing line range or in a focal line (4) lying focal line (PL) reach, and wherein the at least one collimator (2) emerging light beams (S2) from the exit lens (3) at least in vertical Direction (V) are deflected so that the light emerging from the exit lens (3) light rays (S3) form a light distribution with a light-dark boundary, with the cut-off line as a map of the focal line (PL) or of the focal line region (4) through the exit lens (3), and wherein the at least one collimator (2), the exit lens (3) and the focal line region (4) are integrally formed from a translucent body (101), and at least one Limiting surface (2a) of the at least one collimator (2) in the light-transmissive body (101) propagating light beams (SI, S2) are totally reflected, characterized in that the at least one collimator (2) is formed and arranged such that from at least one collimator (2) emerging light beams (S2) in the vertical direction on the focal line (FL) or in the focal line area (4) are bundled. 2. Lighting unit according to claim 1, characterized in that the outer surface (3a) of the exit lens (3) by a groove-shaped structure in a smooth base surface (BF) is formed, wherein the groove-like structure forming grooves (3b) in a substantially vertical direction run, and preferably in each case two horizontally adjacent grooves (3b) by a, in particular substantially vertically extending, elevation, which preferably extends over the entire vertical extension of the grooves (3b), are separated. 3. Lighting unit according to claim 1 or 2, characterized in that the at least one boundary surface (2a) of the at least one collimator (2) is formed such that on this at least one boundary surface (2a) total-reflected light of the collimator (2 ) light source (1) is radiated converging in the vertical direction, so that it is focused on the focal line (FL) or in the focal line region (4). 4. Lighting unit according to one of claims 1 to 3, characterized in that a central coupling region (2b) of the at least one collimator (2) in the form of a lens, in particular in the form of a free-form lens (2b ') is formed such that over the light coupled into the collimator (2) is radiated converging in the vertical direction so that it is focused on the focal line (FL) or in the focal line region (4). 5. Lighting unit according to one of claims 1 to 4, characterized in that all of the collimator (2) emerging light beams (S2) in the vertical direction on the focal line (FL) or in the focal line region (4) are bundled. 6. Lighting unit according to one of claims 1 to 5, characterized in that the at least one collimator (2), in particular at least one boundary surface (2a) and / or a central coupling region (2b), of the at least one collimator (2), is formed such that in the horizontal direction, the light rays exiting from the at least one collimator (2) are parallel to each other. 7. Lighting unit according to one of claims 1 to 5, characterized in that the at least one collimator (2), in particular at least one boundary surface (2a) and / or a central coupling-in region (2b) is or are designed such that in the horizontal direction, the light beams exiting from the at least one collimator (2) converge, preferably in such a way that the light beams are approximately in the area of the exit lens (3), in particular approximately in the area of the outer surface (3a) of the exit lens (3), cross. 8. Lighting unit according to one of claims 1 to 7, characterized in that it has exactly one collimator (2) with an associated light source (1). 9. Lighting unit according to one of claims 1 to 8, characterized in that the at least one collimator (2) and the exit lens (3) are arranged to each other such that from the at least one collimator (2) exiting light directly, in particular without prior deflection and / or reflection, reaches the exit lens (3). 10. Lighting unit according to one of claims 1 to 9, characterized in that a light exit surface (2d) of the at least one collimator (2) is substantially normal to an optical axis of the exit lens (3). 11. Lighting unit according to one of claims 1 to 10, characterized in that the at least one light source is lower than the focal line area (4) or the focal line (FL), or higher than the focal line area (4) or the focal line (FL ), or at the same height as the focal line area (4) or the focal line (FL). 12. Lighting unit according to one of claims 1 to 11, characterized in that on the underside of the optic body (1) two mutually running optical body outer surfaces (la, lb) form a body edge (4 '), which in the focal line (FL ) or in the focal line area (4) or forms the focal line area. 13. Lighting unit according to claim 12, characterized in that the said at least one collimator (2) facing the optical body outer surface (la) on its outer side at least partially, preferably in its entire area, propagating in itself in the optical body (1) on this Optic body outer surface (la) incident light, light absorbing is formed. 14. Lighting unit according to one of claims 2 to 13, characterized in that at a cutting of the base surface (BF) with first, non-vertical sectional planes (SEI) resulting first base-sectional curves (BSK1) are rectilinear, and wherein the have a sinusoidal profile when cutting the outer surface (3a) with these first cutting planes (SEI) resulting first outer surface section curves (SKI). 15. Illumination unit according to claim 14, characterized in that the first outer surface sectional curves (SEI) in the first sectional planes (SEI), with respect to the basic sectional curve (BSK1) of the respective first sectional plane (SEI), are proportional to sinN (k * x), with N = 1, 2, 3, ...., where x denotes the coordinate along the respective basic intersection curve (SEI) and k denotes a constant. 16. Illumination unit according to claim 15, characterized in that the zero crossings of the sinusoidal first outer surface sectional curves (SEI) lie on the first base intersection curves (BSK1). 17. Lighting unit according to claim 15 or 16, characterized in that the value for the constant k is identical for all first outer surface sectional curves (SEI). 18. Lighting unit according to one of claims 2 to 17, characterized in that in a cutting of the base surface with second, vertical sectional planes (SE2), which parallel to an optical axis (Z) of the exit lens (3) extend, resulting second base Curved curves (BSK2) curved, in particular outwardly curved, are formed, wherein preferably the second base-sectional curves (BSK2) are continuous. 19. Lighting unit according to claim 18, characterized in that at a cutting of the outer surface (3a) with defined second cutting planes (SE2) resulting second outer surface sectional curves (SK2) points of the outer surface (3a) with a maximum distance to the base surface (BF ) connect with each other. 20. Illumination unit according to claim 19, characterized in that, when proceeding along the second basic sectional curve (BSK2) in the defined sectional planes (SE2), the normal distance to the second outer surface sectional curve (SK2) is a function A (s) of a parameter s indicative of the position on the second basic intersection curve (BSK2). 21. The lighting unit as claimed in claim 20, characterized in that, as it progresses along the second basic sectional curve (BSK2), the normal distance A (s) increases continuously, the normal distance at a lower edge of the base surface (BF) preferably being smaller than at an upper edge of the base surface, wherein the normal distance A (s), for example, according to the relationship A (s) = Ao * (K - s), with s [0,1], where s = 0 the upper edge and s = 1 the lower edge, and K = 1 or K> 1, where Ao is the normal distance at an upper or lower, preferably the upper edge of the base surface (BF). 22. Lighting unit according to one of claims 2 to 21, characterized in that the outer surface (3a) of the exit lens (3) is curved in the vertical direction outwards, and preferably in the horizontal direction is rectilinear, and for example, by a cylindrical surface with a straight cross-section along an outwardly convex curve is formed. A lighting unit according to any one of claims 1 to 22, characterized in that the at least one light source (1) comprises one or more semiconductor-based light-emitting elements, e.g. a light emitting diode or a plurality of light emitting diodes, and / or e.g. at least one laser light source comprising at least one laser diode having at least one conversion layer. 24. Lighting device comprising at least two lighting units according to one of claims 1 to 23, wherein preferably the light-transmitting body (101) of the lighting units are horizontally adjacent to each other and / or one above the other. 25. Lighting device according to claim 24, that the translucent body (101) of the at least two lighting units are connected to each other, preferably integrally formed. 26. Motor vehicle headlight with at least one lighting unit according to one of claims 1 to 23 or with at least one lighting device according to claim 24 or 25.