EP3699486A1 - Headlamp comprising a plurality of semiconductor light sources and a one-piece primary optical field - Google Patents

Abstract

A headlight with semiconductor light sources, a one-piece primary optics field and secondary optics is presented, the semiconductor light sources being arranged in at least one row, the primary optics field for each semiconductor light source having a primary optics sub-area, which are also arranged in a row, with each primary optics sub-area having a light entry surface and a light exit surface has, wherein through the light entry surface and the light exit surface and wherein the secondary optics are set up to map the light exit surfaces of the primary optics subregions in a light distribution of the headlight. The headlight is characterized by the fact that the light entry surfaces and the light exit surfaces of the primary optic subareas are free-form areas that are separated from one another by sharp edges between them, and the shape of the light exit areas of primary optic subareas not located at the beginning or end of a line differ from one another.

Description

The present invention relates to a headlight according to the preamble of claim 1. Such a headlight is from DE 10 2013 214 116 B4 known. The known headlight has a plurality of semiconductor light sources, a one-piece primary optics field and secondary optics. Each semiconductor light source has a main emission direction. The semiconductor light sources are arranged in at least one row, the one-piece primary optics field having a primary optics sub-area for each semiconductor light source. The primary optics subareas are also arranged in at least one line. Each primary optics subarea has a light entry surface facing a semiconductor light source and a light exit surface facing the secondary optics, exactly one main emission direction of exactly one semiconductor light source runs through the light entry surface and the light exit surface of one primary optics subregion. Due to its light-deflecting properties and its arrangement, the secondary optics are set up to image the light exit surfaces of the primary optics subareas in a light distribution of the headlight.

Compared to earlier headlights, current headlights have to meet greatly changed requirements in terms of the functions to be fulfilled by their light distribution and the quality of the light. The focus is on the safety of all road users and the active support of the driver. The new requirements are defined on the one hand by legal requirements, on the other hand and in particular by automobile manufacturers.

This applies in particular to adaptive headlights, and in particular to so-called matrix headlights. This is understood to mean headlights whose light distribution is composed of horizontally and / or vertically adjoining partial light distributions, different partial light distributions being generated by different and individually controllable light sources. The resulting overall light distribution can therefore be automatically switched on and off and / or dimming of individual or multiple light sources to the current one Adapted to the traffic situation. The current traffic situation is recorded by environment sensors of the motor vehicle, such as radar or infrared sensors, and possibly also additionally by communication between electronic devices of different road users.

Both the high requirements of the automobile manufacturers with regard to the variability and complexity of the matrix light distribution as well as the strict legal requirements for partial high beam systems must be met.

From the DE 10 2013 112 639 A1 a headlight with a plurality of semiconductor light sources arranged in a matrix with a common projection lens for illuminating different areas of low beam distributions is known. From the US 7,815,350 B2 a headlight is known which has an arrangement of 3x3 semiconductor light sources, each with an arrangement of primary optics in front of a common secondary optics in the form of a lens.

A specific application of a projection system with matrix-like arranged semiconductor light sources and primary optics for high beam functions is from DE 10 2008 036 193 A1 known. The DE 10 2008 013 603 B4 as well as the DE 10 2008 044 967 B4 show details of an optical concept that works with a primary optics array and a secondary optics in the form of a lens. This so-called primary optics array consists of a matrix arranged imaging elements that shape the light emanating from semiconductor light sources by total internal reflections on side surfaces of the imaging elements. The DE 10 2008 044 968 A1 shows a light distribution of such a multi-row matrix system.

The DE 10 2009 053 581 B3 shows not only the structure of such matrix lens attachments with a bundling optical effect, but also the application of the light distribution generated with them as partial high beam or glare-free high beam. A central aspect of the optical effect of these matrix lens systems is the avoidance of glare from scattered light, which is why each LED is assigned a main exit lens that illuminates a defined area in the light distribution. The auxiliary optics ensure that light which passes into an adjacent main exit optic does not lead to glare in partial high beam mode.

The matrix systems described in the prior art are limited in terms of the variability and flexibility of their segments in the design stage. In most cases, segments of one and the same size are used, which severely restricts the light distribution generated in this way, both in terms of its resolution and, in particular, of its width.

Furthermore, the listed documents, which use primary optics, show a high level of complexity of the components concerned. Front-end optics that use totally reflective geometries to focus the coupled-in light place the highest demands on the Manufacturing and positioning tolerances to be observed. In most cases, the demanding and cost-intensive material silicone must be used for these geometries, which severely limits the robustness and economic efficiency of the system.

Many current matrix systems use a large number of optical components in order to serve the demanding customer requirements. These are, for example, different segment sizes, intensity gradients within the segments and the extent of the overall light distribution (height and width).

This fact not only makes most matrix systems very expensive, but also leads to a complex structure which requires a high-precision adjustment of the components to one another. If, on the other hand, a smaller number of optical components is used, there are often limitations with regard to the segment division, since only one or a few segment sizes can be implemented within the light distribution.

A few systems with direct imaging concepts do have a certain flexibility in the design of the matrix light distribution, but they require high-precision, multi-part lens attachments with totally reflective geometries. These primary optics place the highest demands on the choice of materials, manufacture and positioning of the filigree structures, which represents a considerable cost factor and has a negative impact on the robustness of the systems concerned.

A high level of complexity of the matrix systems, whether due to sophisticated front-lens concepts or the use of numerous optical components, increases the susceptibility to stray light if the manufacturing and setting tolerances are too high. If the amount of scattered light is too high, compliance with legal requirements for these systems in partial high beam operation is at great risk due to glare.

The object of the invention is to provide a headlight of the type mentioned at the outset which, in the design stage, places flexible and variable changes to a matrix light distribution to be generated and at the same time places minimal conditions on manufacturability and tolerances.

The present invention differs from the prior art mentioned at the beginning in that the light entry surfaces and the light exit surfaces of the primary optics subareas are free-form surfaces, whereby adjacent light entry surfaces are separated from one another by a sharp first edge lying between them and adjacent light exit surfaces are separated from one another by a second lying between them sharp edge are separated from one another, and wherein the at least two light exit surfaces of primary optics subregions not located at the beginning or end of a line differ from one another in their shape.

The one-piece primary optics field is an essential element that, as a primary optical component, forms the light for the secondary optics. Through the special arrangement of different lens-shaped primary optics subareas in a common, one-piece primary optics field, these required properties can be realized in an extremely robust system.

As a result, matrix light distributions with high variability can be implemented with a comparatively small number of optical components.

A preferred embodiment is characterized in that the secondary optics are arranged so as to be focused on the light exit surface of the primary optics subregions.

As a result, the light exit surface is mapped directly by the secondary optics as a headlight distribution. The local intensities on the light exit surface are mapped directly onto the street.

It is also preferred that all light sources are arranged in one plane and that their light exit surfaces face the secondary optics.

As a result, an inexpensive and robust flat printed circuit board can be used to supply the semiconductor light source with electrical energy and to control the semiconductor light sources. In addition, a coherent heat sink with a flat surface that is easy to manufacture can be used to cool the semiconductor light sources.

It is further preferred that each primary optics subarea forms a free-form lens in which light from Semiconductor light source, the main emission direction of which runs through the light entry surface and the light exit surface of the primary optics sub-area, passes through the primary optics sub-area without experiencing total internal reflection and emerges from the light exit area.

As a desired consequence, the optical effect of the primary optics subregions thus acting as lenses is determined by the shape of the light entry surface, the shape of the light exit surface and the refractive index of the transparent material of the primary optics field. The primary optics subareas are preferably arched on both sides and thus each form biconvex lenses. There are no lateral guide surfaces on which internal total reflections could take place. The desired consequence is simple adaptability of the primary optics field in the design stage of the headlight. As a result of the design as biconvex lenses, which adjoin one another in sharp edges, an injection molding tool that is inexpensive to manufacture can be used for the manufacture of the primary optics field. The negative of the sharp edge arises as it were by itself when the injection molded part is milled. This results in a cost saving due to lower tool costs.

Another preferred embodiment is characterized in that the optical surfaces (ie the light entry surfaces and the light exit surfaces) of the primary optics subregions are not all the same in the line direction lying transversely to their optical axis Have width. It is particularly advantageous to provide smaller primary optics sub-areas in the central area of the line than in the outer edge areas. Since each primary optics sub-area preferably converts light from exactly one semiconductor light source and the semiconductor light sources are preferably identical to one another, greater brightness and better resolution of the light distribution in their central area is achieved. At the same time, with an appropriate configuration of the outer primary optics subareas, a desired small brightness gradient can be achieved in the outer areas of the light distribution.

It is also preferred that the light entry surfaces and the light exit surfaces of the primary optics subareas do not all have the same height in the direction transverse to their optical axis and transverse to the line direction. Since the light exit surfaces are mapped as components of the light distribution, this configuration makes it possible to vary the height of the light distribution along its width.

It is further preferred that the primary optics field has asymmetrical primary optics subregions. This can e.g. serve to generate a desired small brightness gradient at the side edges of the light distribution of the headlight.

Another preferred embodiment is characterized in that the one-piece primary optics field is one-line. A single-line version is particularly suitable for Generation of a high beam distribution and / or a partial high beam distribution.

It is also preferred that the primary optics field has multiple lines. This configuration is particularly suitable for generating low beam distributions and high beam or partial high beam distributions.

It is further preferred that the primary optical field has a two-line area and a single-line area, and that the two-line area extends in the line direction only over part of the length of the single-line area lying in the line direction.

In this way, with a comparatively small number of light sources, a fine resolution of the segments in the center and, at the same time, a high width of the overall light distribution can be ensured by arranging segments that become wider in the outer area. These features advantageously all contribute to a reduced development effort in the design of the optical surfaces and to a high degree of flexibility in the adaptation to the requirements of the automobile manufacturer.

Another preferred embodiment is characterized in that the primary optics field has on its light entry surface at least one rib protruding from the light entry surface in the direction of the optical axes of the primary optics subregions and extending between the lines in the line direction.

Such a rib can prevent undesired crosstalk from one primary optics sub-area into an adjacent primary optics sub-area.

It is also preferred that the width and / or height of the primary optics subareas is in the range from 0.5 to 10 millimeters.

It is further preferred that the length of the entire primary optics field in the row direction is between 10 and 100 millimeters.

Another preferred embodiment is characterized in that the primary optics field is part of a one-piece component which, in addition to the primary optics field, has a frame structure having fastening structures and / or reference structures. This configuration minimizes the number of parts required. The reduction in the number of components contributes to cost savings and facilitates production by eliminating the need for adjustment steps. Advantageously, the overall system is robust, i.e. insensitive to mechanical (positioning) tolerances.

It is also preferred that the one-piece component consists of PMMA or PC.

Due to the curvatures and geometries, which can be produced very well from a production point of view, this type of primary optics can be produced from conventional plastics such as PMMI and PC and allows the Use of a more expensive and difficult to process material such as silicone.

Likewise, due to the simple structure of the primary optics component, corrections can easily be carried out in the injection molding tool used for its production. Furthermore, the assembly of the primary optics component is very simple and precise, for example by means of corresponding screw points in a frame geometry. In comparison to silicone-based and totally reflective coupling structures having front optics, this saves a filigree holder by means of additional components as well as a complex alignment of the light guides of these totally reflecting coupling structures to the semiconductor light sources.

Last but not least, such a matrix system can be adapted to new customer requirements simply by changing the individual lens elements within the ancillary optics, without having to rework a large number of components, which is time-consuming and costly.

Overall, the invention in connection with the various configurations results in manifold advantages, in particular a high variability of the matrix light distributions with regard to different resolutions and segment widths within the light distribution. The invention can be used both in projection systems and in reflection systems. The primary optics field offers the possibility of a flexible design of matrix light distributions with regard to the number of their segments, the number of lines (single or multi-line), the extent of the individual segments and the width of the overall light distribution. The complexity of the design and manufacture of the auxiliary optics is considerably reduced compared to the prior art. The requirement for the lateral extension of the matrix light distribution is generated very well with only one component, in that suitable individual lenses of corresponding segment width are arranged next to one another in order to achieve a sufficient width of the ancillary optics. The primary optics field, in conjunction with a projection lens as secondary optics, due to only two optical components, leads to a robust system that has very low demands on manufacturing tolerances. A complex adjustment of the optical components (primary optics field and secondary optics) to one another is not necessary. The invention can be used to generate individual types of light distribution (mono function, single-line, high-beam function) and several types of light distribution (bi-function, multi-line, for example a combination of low beam and high beam functions). With a bi-function, some of the segments contribute to the low beam. These segments are usually arranged in the lower area of the light distribution. The remaining segments arranged further up form the matrix light distribution for a partial high beam function and a high beam function. Due to the one-piece primary optics field according to the invention, further optical components can possibly be dispensed with and thus considerable costs can be saved. The complexity of the overall system decreases.

Further advantages emerge from the description and the attached figures.

It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the respectively specified combination, but also in other combinations or alone, without departing from the scope of the present invention.

• Figur 1 einen Ausschnitt aus einem einzeiligen Primäroptikfeld eines erfindungsgemäßen Scheinwerfers;
• Figur 2 einen Ausschnitt aus einem zweizeiligen Primäroptikfeld eines erfindungsgemäßen Scheinwerfers;
• Figur 3 einen Ausschnitt aus einer Lichtaustrittsfläche eines abschnittsweise einzeiligen und zweizeiligen Primäroptikfeldes;
• Figur 4 einen Ausschnitt aus einer Lichteintrittsfläche eines abschnittsweise einzeiligen und zweizeiligen Primäroptikfeldes;
• Figur 5 eine schematische Darstellung einer Anregung einer nicht eingeschalteten Halbleiterlichtquelle einer ersten Zeile durch eine benachbarte Halbleiterlichtquelle einer zweiten Zeile und an einer Lichteintrittsfläche auftretenden Reflexionen;
• Figur 6a eine schematische Darstellung einer Anregung einer nicht eingeschalteten Halbleiterlichtquelle einer ersten Zeile durch eine benachbarte Halbleiterlichtquelle einer zweiten Zeile und an einer Lichtaustrittsfläche auftretenden Reflexionen;
• Figur 6b eine Anordnung von Halbleiterlichtquellen, einem einstückigen Primäroptikfeld und einer Sekundäroptik;
• Figur 7 ein Beispiel einer zusätzlichen, zwischen zwei Zeilen verlaufenden Rippe;
• Figur 8 ein Ausführungsbeispiel eines Primäroptikbauteils mit einem zweizeiligen Primäroptikfeld;
• Figur 9 ein Ausführungsbeispiel eines Primäroptikbauteils mit einem einzeiligen Primäroptikfeld;
• Figur 10 ein Ausführungsbeispiel eines erfindungsgemäßen Kraftfahrzeugscheinwerfers in bestimmungsgemäßer Lage in einem Horizontalschnitt einen Horizontalschnitt durch ein Ausführungsbeispiel eines erfindungsgemäßen Scheinwerfers;
• Figuren 11 bis 14 Darstellungen einzeiliger und zweizeiliger Matrix-Lichtverteilungen, wie sie mit Ausführungsbeispielen erfindungsgemäßer Scheinwerfer erzeugbar sind;
• Figur 15 ein einstückiges Primäroptikfeld, das einen mehrzeiligen Bereich und einen einzeiligen Bereich aufweist; und
• Figur 16 einen Vertikalschnitt durch einen ohne Gehäuse und Abdeckscheibe dargestellten erfindungsgemäßen Scheinwerfer.

Exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description. The same reference symbols in different figures denote the same or at least comparable elements in terms of their function. They show, each in schematic form:

• Figure 1 a section from a single-line primary optics field of a headlight according to the invention;
• Figure 2 a section from a two-line primary optics field of a headlight according to the invention;
• Figure 3 a section from a light exit surface of a single-line and two-line primary optics field in sections;
• Figure 4 a section from a light entry surface of a sectionally single-line and two-line primary optics field;
• Figure 5 a schematic representation of an excitation of a semiconductor light source that is not switched on first line by an adjacent semiconductor light source of a second line and reflections occurring at a light entry surface;
• Figure 6a a schematic representation of an excitation of a non-switched semiconductor light source of a first row by an adjacent semiconductor light source of a second row and reflections occurring at a light exit surface;
• Figure 6b an arrangement of semiconductor light sources, a one-piece primary optics field and a secondary optics;
• Figure 7 an example of an additional rib running between two rows;
• Figure 8 an embodiment of a primary optics component with a two-line primary optics field;
• Figure 9 an embodiment of a primary optics component with a single-line primary optics field;
• Figure 10 an embodiment of a motor vehicle headlight according to the invention in the intended position in a horizontal section a horizontal section through an embodiment of a headlight according to the invention;
• Figures 11 to 14 Representations of single-line and two-line matrix light distributions as can be generated with exemplary embodiments of headlights according to the invention;
• Figure 15 a one-piece primary optics panel having a multi-line area and a single-line area; and
• Figure 16 a vertical section through a headlight according to the invention shown without a housing and cover plate.

In detail, the Figure 1 a section from a single-line primary optics field 10. The primary optics field 10 has individual primary optics subareas 12. The primary optics subareas 12 each have a convexly curved light entry surface (in the Figure 1 covered) and a convexly curved light exit surface 14. Each primary optics subarea 12 forms a bi-convex lens. In each case one primary optics sub-area 12 is in the Figure 1 assigned semiconductor light source, not shown. Each pair of a semiconductor light source and a primary optics subarea 12 generates a segment in the light distribution of a light distribution generated overall by a headlight. These segments can differ from one another in terms of their properties, such as width and height. These differences are generated in that the optical surfaces of the primary optics subareas 12, that is to say the light entry areas and the light exit areas 14, differ from primary optics subarea 12 to primary optics subarea 12. The optical surfaces of the individual lenses are separately narrower or wider (segment width) and lower or higher (Segment height) designed. In the Figure 1 the primary optics subregions 12 become narrower from left to right (opposite to the y direction), while their height (in the z direction) does not change.

Typically, these individual segments are between 1 ° and 10 ° high in the light distribution in the z-direction, but can also have a lower or greater height. This also applies to the width of the segments (in the y-direction).

The optical surfaces of the primary optics subareas 12 are simple free-form surfaces which are calculated in such a way that they generate the desired segments in cooperation with the secondary optics without the use of further optical elements, in particular without the use of a shading screen. The optical surfaces can, for example, be aspheres or other lens surfaces that determine the intensity profile within the segments of the light distribution. Usually the intensity profile within the segments shows a concentration of the light towards the horizon, while the intensity deliberately decreases upwards and downwards.
The widths of the optical surfaces, for example the light entry surfaces 26, in the line direction and the height of these optical surfaces transversely to the row direction (y-direction) and transversely to the optical axis (x-direction) of the primary optics subareas are preferably between 1mm and 10mm, but can also have lower or higher values.

If a pure high beam function is desired, the primary optics subareas 12 of the LEDs can be arranged next to one another in a single row, as shown in FIG Figure 1 is shown. The associated primary optics subareas 12 are blended with one another in such a way that they are delimited by sharp edges 16 running between them. In particular, there are no fillets with steps or radii between them. These sharp-edged boundaries are essential for the function of the headlight.

The primary optics subareas 12 can be designed asymmetrically so that a segment of the light distribution generated by a primary optics subarea 12 has a different lateral extent to the right and left and / or to the top and bottom. A full high beam distribution is obtained, for example, by switching on a coherent subset of the associated semiconductor light sources (LEDs). A partial high beam distribution results when individual semiconductor light sources of the partial set are dimmed or switched off, as a result of which associated segments of the resulting light distribution of the headlight are less brightly or not illuminated.

Figure 2 shows a multi-line primary optics field 10. Such a primary optics field 10 opens up the possibility of generating both a low beam distribution and a high beam distribution and partial high beam distribution. A certain number of primary optics subareas 12.1 of one line 18 of the Primary optics field 10 together with the associated semiconductor light sources a low beam distribution. The other semiconductor light sources are only used in high beam mode or partial high beam mode.

Figure 2 Using the example of an individual primary optics subarea, shows how such a primary optics subarea 12 is delimited by sharp edges 16. These edges 16 are each continuously convexly curved. The line 17 running transversely across the light exit surface 14 of this primary optics sub-area 12, on the other hand, has locally convex sections and locally concave sections. This results from the fact that the primary optics subareas do not have simple lenses (each having a light entry and a light exit focal point), but rather that the primary optics subareas 12 are intersected with one another and delimited by freeform surfaces and are pillow-shaped, arched on both sides of the primary optics field 10. The partially convex and partially concave boundary lines can run in the y-direction and in the z-direction and in every direction lying in between over the light exit surface and / or the light entry surface of the primary optics part area. The light exit surfaces are imaged directly by secondary optics, without the light emitted by the light sources emanating from the light exit surfaces being shaped by an additional screen. The free-form surfaces that delimit the primary optics subareas are shaped in such a way that they form an archetype of a segment of the light distribution that is generated by the Secondary optics is projected.

Both the single-line and the two-line primary optics fields 10 enable partial high beam operation as a so-called matrix high beam, in which individual segments or pixels of the light distribution of the headlight can be specifically illuminated more or less brightly. By skillfully controlling the individual light sources, if the light distribution of the headlamp is sufficiently horizontal, it is also possible to pivot a low beam distribution or a high beam distribution with such a two-line primary optical field free of mechanics. For this purpose, groups of semiconductor light sources arranged contiguously in the row direction are sequentially controlled in such a way that the actively luminous light exit surface of the primary optics field is laterally shifted to the right or left.

In order to reduce the number of semiconductor light sources to be used, for example for reasons of cost, the primary optics field can have a two-line area and a single-line area, the two-line area extending in the line direction only over part of the length of the single-line area lying in the line direction. In this way, with a comparatively small number of semiconductor light sources, a high (fine) resolution of the segments in the center of the resulting light distribution and, at the same time, a large width of the resulting light distribution can be achieved if the primary optics subareas become wider and thus wider in the outer area of the line (s) nascent segment are arranged.

Figure 3 shows a section from a light exit surface 14 of a two-line primary optics field 10 and Figure 4 shows a corresponding section of a light entry surface 26. Both figures illustrate the transition between a two-line sub-area and a single-line sub-area in which the height (in the z-direction) of the primary optic sub-area 12.3 of the single-line sub-area is greater than the height of the primary optic sub-areas in the two-line part, but smaller than the height of the sum of the two lines 18, 20, the flexibility of the design of the primary optics field 10 of headlights according to the invention.

In a particular embodiment, the line 20 is designed so that there is a special contour downwards which, as a result of the imaging by the projection lens, ensures a decrease in the brightness of the high beam upwards. A plane which is parallel to the XZ plane and which contains the optical axis of a lens reaches an intersection curve with the lens line 20, the local radius of which increases downwards. The radius of the light entry side of a lens in the high beam line is larger than the radius on the light entry side of the first line 18. In order for the brightness to flow gently upwards, the lower surfaces of the lens line 20 are pulled down until the front and back of the lens intersect . (recognizable in Fig. 3 below the lens element 12.3 and at the lens element 12.3 itself). So the upward extended high beam partial areas of the Figures 11-14 be generated.

With regard to compliance with the legal requirements of matrix systems in partial high beam applications, avoidance of scattered light is essential. In order to avoid dazzling oncoming road users and those driving ahead, so-called crosstalk must be prevented. Crosstalk is understood here to mean the occurrence of scattered light in a segment of the light distribution whose associated light source is dimmed or switched off, this light source being stimulated to glow by scattered light emanating from neighboring light sources, with which light falls undesirably into a segment that is dark should be.

Scattered light can have various causes. On the one hand, light from a semiconductor light source, which is coupled into an associated primary optics sub-area, can reach an adjacent primary optics sub-area by scattering. On the other hand, hollow fillets and steps lying between adjacent primary optics subregions can act as scattering or incorrectly imaging objects which can cause scattered light in any areas of the light distribution. In order to minimize these stray light contributions, the design according to the invention of the primary optics field 10 with the sharp-edged boundaries of the primary optics subregions is essential.

Another important aspect for avoiding scattered light is the avoidance of excitation of semiconductor light sources that are not switched on by light incident undesirably from neighboring light sources.

Figure 5 shows an excitation of a non-switched-on semiconductor light source 22.1 of a primary optics sub-area 12.1 of a first line by an activated adjacent semiconductor light source 22.2 of a primary optics sub-area 12.2 of a second line and reflections occurring on light entry surfaces 26 of the associated primary optics sub-areas 12.1, 12.2. A phosphor layer of neighboring semiconductor light sources can be excited to give off undesired glow (fluorescence) by light 28 from switched-on semiconductor light sources.

Figure 6a shows an excitation of a non-switched semiconductor light source 22.1 of a primary optics subarea 12.1 of a first line by light 28 from an activated adjacent semiconductor light source 22.2 of a primary optics subarea 12.2 of a second line and reflections occurring on a light exit surface 14 of the primary optics subareas.

Both for the Figure 5 as well as for the Figure 6a it is true that an excited semiconductor light source in turn undesirably illuminates a segment of the light distribution that is supposed to be dark.

Figure 6b shows, purely schematically and deviating from the actual size relationships, an arrangement of semiconductor light sources 22, a one-piece primary optics field 10 and secondary optics 48 together with three different beam paths 100, 102, 104. In fact, the distance (object distance) of the semiconductor light sources 22 is relatively small to the light entry surfaces of the primary optics field facing them. In order to direct the light from the semiconductor light sources 22 onto the secondary optics 48, the primary optics subregions 12 have a distinct surface curvature on the light entry side and light exit side for the small object width and are intersected with the sharp edges 16 along approximately straight lines. As a result of these geometric relationships, essentially only those rays 100 which come from the semiconductor light source 52 associated with this primary optics sub-area 12 fall through a specific primary sub-area 12 onto the secondary optics. Rays 102 which fall from a semiconductor light source 22 onto another primary optics area not belonging to this semiconductor light source miss the secondary optics and therefore do not contribute to the light distribution.

The individual partial light distributions of the various semiconductor light source channels, each consisting of a semiconductor light source and an associated primary optics sub-area, can thus be activated and deactivated independently of one another. The channels of adjacent semiconductor light sources 22 and thus of adjacent primary optics subregions 12 directly adjoin one another and thus the light distributions also adjoin one another directly and, if necessary, can also overlap slightly at the respective edge. Additional structures on the projection lens can homogenize the individual light distributions and their transitions. Scattered rays 104 of a light source 22 are at the sharp edge 16 and due to the oblique incidence and The pronounced curvature of the light entry surfaces of neighboring primary optics subregions prevents them from falling on neighboring semiconductor light sources, when they are switched off, to stimulate them to glow. This effectively reduces the undesired co-lighting effect.

Furthermore, rays that have entered the primary optics through the entry surface of the primary optics can also enter adjacent channels there in a disruptive manner due to total reflection. This possibility is also reduced by the sharp transition edges and pronounced curvature of the surfaces.

Suitable values or ratios of values of dimensions and spacings are given below with reference to the Figure 16 specified.

In order to minimize unwanted stray light contributions from such back reflections, an additional rib 30 running between two lines can be used, as shown in FIG Figure 7 is shown. Such a rib 30 protrudes from the light entry surface 26 of the primary optics field 10 and runs in the line direction y at the transition between adjacent primary optics subregions 12.1, 12.2 of two lines. It extends in the line direction y over several primary optics subareas. The height of the rib 30 in the direction of the optical axis (x-direction) of the primary optics subareas is preferably less than one millimeter, but can also be significantly larger or smaller in order to have a negative impact on the imaging Avoid properties of the primary optics subareas. The depth of this rib 30 in a direction (z-direction) transverse to the row direction (y-direction) and transverse to its height (x-direction) is to be dimensioned so that the beam path of light reflected back does not end on the phosphor layer of semiconductor light sources .

In addition to the high variability and flexibility in the design of the segments of a light distribution to be generated, the primary optics field 10 used in the invention also has the advantage of being easy to manufacture and the advantage of being highly insensitive to manufacturing-related fluctuations in dimensions. In particular, an adjustment of the primary optics field 10 relative to a projection lens serving as secondary optics is not necessary for this robust matrix system. Long tolerance chains of conventional systems that have more optical and mechanical components are eliminated.

The typical dimensions (width (in the y direction) / height (in the z direction)) of the primary optics subregions 12.1, 12.2 acting as individual lenses are in the range from 0.5 to 10 millimeters. The associated segments within the light distribution have horizontal and vertical opening angles between 1 ° and 10 °. Typical dimensions of the entire primary optics field 10 are usually between 10 and 100 millimeters. However, primary optics fields 10 with smaller or larger dimensions are also possible.

The overall light distribution generated in this way typically has a horizontal width between ± 1 ° to ± 60 ° or more, and a vertical extent in the range from -5 ° to + 10 °.

Figure 8 shows an embodiment of a primary optics component 32 with a two-line primary optics field 10 and Figure 9 shows an embodiment of a primary optics component 34 with a single-line primary optics field 10. Both Figures 8, 9 show the respective primary optics field 10 as part of a one-piece, simply constructed primary optics component 32, 34 which, in addition to the respective primary optics field 10, has screw-on points 36 and possibly also reference structures 38 in a frame structure 40 that are used for positioning. This results in a simple and precise assembly of the primary optics component 32, 34. This lens design also results in the design of the primary lens array in FIG Figure 8 in which the frame structure only runs above the lens array, while in the single-line primary optics component the frame structure can enclose the lens line ( Figure 9 ).

Figure 10 shows an embodiment of a motor vehicle headlight 42 according to the invention in the intended position in a horizontal section. The headlight 42 has a housing 44, the light exit opening of which is covered by a transparent cover plate 46. Inside the housing 44 are a plurality of semiconductor light sources 22, for example LEDs, a one-piece primary optics field 10 and a secondary optics 48 arranged. The secondary optics 48 is, for example, a cylinder lens which has a converging cross section in the xz plane, for example a plano-convex or biconvex cross section.

The semiconductor light sources 22 are arranged in at least one row 50 and preferably all in one plane so that they can be arranged on a flat circuit board 52. Their light exit surfaces 54 face the secondary optics 48. The one-piece primary optics field 10 has a primary optics subarea 12 for each semiconductor light source 22, the primary optics subareas 12 also being arranged in at least one row. The semiconductor light sources 22 are arranged in relation to the primary optics field 10 in such a way that each primary optics sub-area 12 is opposite a semiconductor light source 22. Each primary optics sub-area 12 has a light entry surface 26 facing its semiconductor light source 22 and a light exit surface 14 facing the secondary optics 48. Precisely one main emission direction 56 of precisely one semiconductor light source 22 runs through the light entry surface 26 and the light exit surface 14 of a respective primary optics sub-area.

Due to its light-deflecting properties and its arrangement, the secondary optics 48 are set up to image the light exit surfaces 14 of the primary optics subregions 12 in a light distribution of the headlight 42. In the illustrated embodiment, the secondary optics 48 is a projection lens that is applied to the light exit surfaces of the Primary optics subregions and thus is arranged focused on the light exit surface of the primary optics field. In this example, the light-deflecting properties result from the shape, the refractive index and the arrangement of the projection lens in space.

The light entry surfaces 26 and the light exit surfaces 14 of the primary optics subareas are freeform surfaces. Light entry surfaces that are adjacent to one another are separated from one another by a sharp first edge 16.1 lying between them. Adjacent light exit surfaces are separated from one another by a second sharp edge 16.2 located between them. At least two light exit areas of primary optics subregions 12 not located at the beginning or end of a line differ from one another in their shape.

Each primary optics subarea 12 forms a free-form lens in which light from the semiconductor light source 22, the main emission direction 56 of which passes through the light entry surface and the light exit surface of the primary optics subarea 12, passes through the primary optics subarea 12 without experiencing total internal reflection.

The Figures 11 to 14 show single-line and two-line matrix light distributions as can be generated with exemplary embodiments of headlights 42 according to the invention. Each matrix element represents a pixel in the overall light distribution. The horizontal 0 ° line indicates the position of the horizon when the invention is used as intended in a road vehicle.

The vertical V intersects the horizon at a central point in front of the motor vehicle.

The Figures 11 and 12 show examples of high beam distributions that can be generated with the same headlight. The primary optical field used in this case is a single-line primary optical field. Figure 11 shows a high beam distribution, which is composed of segments of different widths and in which the left and some segments are darkened. The segment width varies between 1.5 ° in the center and 3 ° on the right edge. This ensures broad illumination of the right edge and, at the same time, a smooth transition from light to dark when the segments are illuminated with the same light sources. With the light distribution from the Figure 11 For example, the course of a right-hand bend is illuminated with a high beam distribution. It goes without saying that the segment widths and heights can also have other values and that the values shown in the figures are only examples.

Figure 12 shows a light distribution generated with the same line, in which compared to Figure 11 further segments are illuminated on the left and further segments are switched off on the right. As a result, the driver's attention is intuitively concentrated on a narrow central area.

The Figures 13 and 14 show examples of high beam distributions that can be generated with another headlight. The one used in each case The primary optic field is a two-line primary optic field in the middle and a single-line primary optic field on the right and left edges.

Figure 13 shows a wide high beam distribution for a right turn. This light distribution has on its right side a wide low beam segment and an overlying and equally wide high beam segment. These segments are each illuminated by two LEDs, while the other segments are each illuminated by one LED. A low beam segment is illuminated on the left-hand side and a high beam segment above is darkened. The lighting with several LEDs opens up further possibilities for the design of light distributions, for example in that only one of the two light sources is operated or both light sources are operated together.

Figure 14 shows a symmetrical wide high beam distribution to the right and left. By switching off the LEDs in the upper line (high beam line) and the two edge segments, this results in a low beam distribution.

These schematic representations of single-line and two-line matrix light distributions with different numbers of pixels, different division of the segments and extent of the respective overall light distribution make it clear that the invention presented here enables a highly flexible design of matrix light distributions.

Figure 15 shows, in a highly schematic manner, a one-piece primary optics field 10 which has a multi-line area 108 and a single-line area 106 and which extends over a total length L in the line direction. At least one of the two areas extends in the row direction over a length 1 which is smaller than the total length L.

Figure 16 shows a vertical section through a headlight according to the invention shown without a housing and cover plate. The headlight has a plurality of semiconductor light sources 22, a one-piece primary optics field 10 and secondary optics 48. The semiconductor light sources 22 are arranged in three rows in this exemplary embodiment. The one-piece primary optics field 10 has a primary optics subarea 12 for each semiconductor light source 22, the primary optics subareas 12 also being arranged in three rows. The primary optics subareas 12 are intersected with one another within each line and also from line to line, so that the primary optics subareas are separated from one another by sharp edges 16.

The ratio of the object width 110 of the secondary optics 48 to the object width 112 of the primary optics 10 is typically 50, but can be in the range from 35 to 200, the distance between the light sources 22 and the one-piece primary optics field 10 preferably being 0.5mm to 1.5mm. The size of the light exit surfaces of the light sources 22 is preferably 0.5 mm ² to 1.5 mm ² . The length of the Primary optics field 10 in the line direction (y-direction) is preferably 50 mm to 100 mm. The width / height of the primary optics field 10 is preferably 5 mm to 20 mm in the z direction. The length of the secondary optics in the line direction y is preferably 40 mm to 100 mm. The width / height of the secondary optics is preferably 15 mm to 50 mm in the z direction. The back focal length, that is to say the distance between the primary optics field 10 and the secondary optics 48, is preferably 40 mm to 100 mm.

Claims (15)

Headlight (42) having a plurality of semiconductor light sources (22), a one-piece primary optics field (10) and secondary optics (48), each semiconductor light source (22) having a main emission direction (56), the semiconductor light sources (22) in at least one row ( 18, 20; 50), the one-piece primary optics field (10) having a primary optics sub-area (12) for each semiconductor light source (22), the primary optics subareas (12) also being arranged in at least one line, each primary optics subarea (12) having a a semiconductor light source (22) facing light entry surface (26) and one of the secondary optics (48) facing light exit surface (14), through the light entry surface (26) and the light exit surface (14) each of a primary optics subarea (12) exactly one main emission direction (56) one Semiconductor light source (22) runs through it, and the secondary optics (48) are set up by their light-deflecting properties and their arrangement to image the light exit surfaces (14) of the primary optics subareas (12) in a light distribution of the headlight (42), characterized in that the Light entry surfaces (26) and the light exit surfaces (14) of the primary optics subareas (12) are free-form surfaces, whereby adjacent light entry surfaces (26) are separated from one another by a sharp first edge (16) lying between them, and adjacent light exit surfaces are separated from one another by a second sharp edge lying between them Edge (16) are separated from one another, and wherein the light exit surfaces (14) of at least two primary optics subregions (12) not located at the beginning or end of a line differ from one another in their shape. Headlight (42) according to Claim 1, characterized in that the secondary optics (48) are arranged so as to be focused on the light exit surface of the primary optics subareas (12). Headlight (42) according to one of the preceding claims, characterized in that all light sources (22) are arranged in one plane and their light exit surfaces (54) face the secondary optics (48). Headlight (42) according to one of the preceding Claims, characterized in that each primary optics sub-area (12) forms a free-form lens in which the light from the semiconductor light source (22), the main direction of radiation (56) of which passes through the light entry surface (26) and the light exit surface (14) of the primary optics sub-area (12) Primary optics sub-area (12) passes through without experiencing total internal reflection and emerges from the light exit surface (14). Headlight (42) according to one of the preceding claims, characterized in that the optical surfaces of the primary optical subareas (12) do not all have the same width in the line direction lying transversely to their optical axis Headlight (42) according to one of the preceding claims, characterized in that the optical surfaces of the primary optics subregions (12) do not all have the same height in the direction transverse to their optical axis and transverse to the line direction Headlight (42) according to one of the preceding claims, characterized in that the primary optics field (10) has asymmetrical primary optics partial areas (12). Headlight (42) according to one of the preceding claims, characterized in that the one-piece primary optics field (10) is single-line. Headlight (42) according to one of the preceding claims, characterized in that the one-piece primary optics field (10) has multiple lines. Headlight (42) according to claim 9, characterized in that the one-piece primary optics field (10) has a multi-line area and a single-line area and extends over a total length (L) and that at least the multi-line area extends over a length (1), which is shorter than the total length (L). Headlight (42) according to one of the preceding claims, characterized in that the primary optics field (10) on its light entry surface at least one rib (30) protruding from the light entry surface in the direction of the optical axes of the primary optics subregions (12) and extending between the lines in the line direction having. Headlight (42) according to one of the preceding claims, characterized by a rib (30) running between two lines, which protrudes from the light entry surface (26) of the primary optics field (10) and in line direction at the transition between adjacent primary optics subareas (12.1, 12.2) runs from two lines. Headlight (42) according to one of the preceding claims, characterized in that the primary optics field is part of a one-piece component which, in addition to the primary optics field (10), has a frame structure (40) which has fastening structures and / or reference structures and which completely encircles the primary optics field. Headlamp (42) according to one of claims 1 - 13, characterized in that the primary optics field is part of a one-piece component which, in addition to the primary optics field (10), has fastening structures and / or reference structures and only partially encircles the primary optics field ), the frame structure being one-sided like a u. Headlight (42) according to claim 14, characterized in that the one-piece component consists of PMMA or PC.

Images