WO2011154470A1

WO2011154470A1 - Attachment optical unit composed of transparent material for concentrating light, lens array comprising at least one such attachment optical unit and light module comprising such a lens array

Info

Publication number: WO2011154470A1
Application number: PCT/EP2011/059543
Authority: WO
Inventors: Wolfgang Hossfeld
Original assignee: Automotive Lighting Reutlingen Gmbh
Priority date: 2010-06-09
Filing date: 2011-06-09
Publication date: 2011-12-15

Abstract

The invention relates to an attachment optical unit (28) for concentrating light from a light source (22) assigned to the attachment optical unit (28) by refraction during passage through a light entrance surface (36) and/or a light exit surface (38) of the attachment optical unit (28) and/or by total reflection at an interface (34) of the attachment optical unit (28). A main exit direction (42) of the concentrated light from the attachment optical unit (28) is remitted to a main emission direction (32) of the light source (22) in a specific manner. In order to be able to direct light emitted by the light source (22) in a desired main exit direction independently of the main emission direction of the light emitted by the light source (22), it is proposed that at least one of the interfaces (34) of the attachment optical unit (28) be embodied in such a way that the main exit direction (42) of the light beam runs at an angle with respect to the main emission direction (32) of the at least one light source (22).

Description

Front optics made of transparent material for bundling light, lens array with at least one such intentional optics and light module with such a lens array

The present invention relates to an attachment optics for bundling light of at least one light source associated with the attachment optics. The attachment optics consists of a transparent material and has light entry surfaces through which at least part of the light emitted by the at least one light source enters the intent optics, totally reflecting interfaces on which at least a portion of the entered light is totally reflected, and light exit surfaces through which at least a portion of the incident light optionally emerges after at least one total reflection at one of the interfaces of the optical attachment. The bundling of the light emitted by the at least one light source is effected by refraction when passing through one of the light entry surfaces and / or when passing through one of the light exit surfaces and / or by total reflection at one of the interfaces. The attachment optics has a main exit direction of the bundled light with respect to a main emission direction of the at least one light source.

The invention also relates to an optical array comprising a plurality of adjacent optical systems of the abovementioned type, one above the other and / or offset from one another. The optical array is designed to bundle light from light sources associated with the optical attachments.

Finally, the invention also relates to a light module of a lighting device of a motor vehicle, comprising a plurality of arranged on a planar support member light sources for emitting light with substantially parallel main radiation directions and an optical array of the type mentioned above.

Such an attachment optics can be used in any illumination device of a motor vehicle, for example in a headlight or any lamp. In particular, a semiconductor light source, in particular a light-emitting diode (LED), is used as the light source. An attachment optics can be assigned to one or more light sources. A light module of a lighting device may comprise one or more additional optics with their associated light sources. A light module preferably generates any desired light distribution, for example (in the case of white light) a daytime running light, a dipped beam, a high beam, a position, limiting or parking light, a reversing light or any other dynamic headlight function (eg, partial high beam or marker light) red light), a tail light, a brake light or a rear fog light or (in the case of yellow or orange light) a flashing light or a side marker light. Of course, it is conceivable that a light module generates only a part of a light distribution and the complete light distribution results from a superposition of the individual partial light distributions.

The attachment optics serves for bundling the light emitted by the at least one light source assigned to the attachment optics. For this purpose, the light emitted by the at least one light source is coupled via the at least one light entry surface into the attachment optics and coupled out again after passing through the attachment optics via the at least one light exit surface. The at least one light entry surface and / or the at least one light exit surface can be convexly curved so that the surfaces can fulfill the function of a converging lens. It is bundled by the refraction of the light when coupled into the attachment optics and / or when decoupling from the attachment optics. In addition, lateral boundary surfaces of the attachment optics are formed obliquely such that a part of the coupled-in light impinges on the boundary surfaces and is totally reflected by them in the direction of the at least one exit surface. The total reflection of a portion of the coupled-in light causes not only the refraction at the light entry surface and / or the light exit surface but also the bundling of the light.

From DE 486 303 a front optics of the aforementioned type is known, which consists of a arranged on the optical axis central lens element and a surrounding the lens catadioptric ring element whose outer surface totally reflects the light of a light source. The optics can also be referred to as TIR (Total Internal Reflection) lens. By the known optical attachment optics, the light of a light source whose light radiates in the half-space in the direction of the optical axis of the optics can be efficiently collected and bundled. This known attachment optics has served as the basis for various special variants and developments, some of which are mentioned below.

From DE 2 201 574 A1 a TIR lens is known in which the surfaces of the catadioptric ring are designed so that no refraction takes place at the light entry and exit surfaces. DE 10 2009 021 182 A1 describes a non-rotationally symmetrical TIR lens which generates a light distribution whose light intensity increases with increasing radiation angle before it drops again. In addition, numerous optical systems are known whose component is one or more TIR lenses. An example is a projector in which the light of an LED is bundled by a TIR optic (see EP 1 159 563 A2). US Pat. No. 7,222,995 B1 describes a luminaire in which a light distribution which results from overlapping of the individual light distributions is generated by a plurality of LEDs with associated rotationally symmetric TIR lenses whose optical axes are inclined relative to one another. By suitable tilting of the axes to each other, the light distribution and in particular the maximum illuminance should be optimized.

WO 02/33449 A2 describes a one-part array of rotationally symmetrical, identically designed TIR lenses. Due to the symmetry of the TIR lenses, the main exit directions of the individual TIR lenses can only run parallel to one another. In addition, the main emission directions of the light sources are always parallel to the main emission directions of the attachment optics. With the known lens array, the main exit directions of the individual TIR lenses can thus be targeted only by tilting the individual light sources and the TIR lenses assigned to them so that the main exit directions extend in the desired directions. However, this means that the light sources can no longer be arranged on a plane with mutually parallel main emission directions. The known lens array thus requires a high-precision alignment of both the front optics and the individual light sources, whereby the production cost is very high. A targeted alignment of the main exit directions of the light bundles from the individual intent optics may be useful, for example, so that the main exit directions converge in one point or in one point area (a point cloud).

Based on the described prior art, the present invention therefore has the object of designing a lens attachment in such a way that it allows light emitted by at least one light source associated with the attachment optics to be in a desired light independently of the main exit direction of the light emitted by the at least one light source To direct the main radiation direction. When using several of the attachment optics in an array, it should be possible to focus the light of multiple light sources, the main emission directions are substantially parallel to each other, and direct targeted, so that, for example, the light bundles converge in a point or a dot area and / or in one level behind the array, a desired light distribution can be generated.

To solve the problem, it is proposed, starting from the attachment optics of the type mentioned above, that at least one of the interfaces of the attachment optics is formed such that the main exit direction of the light beam extends at an angle to the main emission of the at least one light source.

The invention is based on the idea of bundling and directing light from a plurality of light sources of a lighting device whose main emission directions are substantially the same, via a lens array with a plurality of the auxiliary optics according to the invention. In this case, the attachment optics are embodied such that at least one of the light sources is associated with intent optics and that the light can be directed by the associated attachment optics from the main emission direction of the respective light source or light source group in any direction for each one of the attachment optics. Preferably, the light is directed in different directions by the attachment optics of the array. That is to say, the center of gravity of the individual light beams or individual light distributions produced does not lie on an axis which is formed from the light source origin and its main emission direction.

With the present invention it is possible to combine a plurality of attachment optics into an array so that the light sources assigned to the individual attachment optics of the array produce a common light distribution in which the individual light distributions overlap in a desired manner, even if the main emission directions of the light sources do not intersect. Since the light directing function of each optical attachment can be controlled by varying the shape of the interfaces within a certain range without causing greater light losses (for example by decoupling a portion of the light), the overlap of the individual light distributions in a given plane behind the Attachment optics array can be controlled so that eg Irradiance, homogeneity or other targets of the resulting total light distribution can be optimized at approximately constant luminous flux.

The light sources are preferably designed as semiconductor light sources, in particular as light emitting diodes (LEDs). The small-sized LEDs allow a small size of the attachment optics or of an optical array composed of a plurality of attachment optics. In addition, the LEDs have low energy consumption and a long life.

The attachment optics according to the invention can e.g. used in projectors, automotive lighting equipment, in particular headlights or lights, or in flashlights, where on the one hand several light sources are to be used to produce a high luminous flux and high illuminance, but on the other hand a simple and therefore cost-effective production is to be achieved by the light sources arranged on one level as an array (eg as SMD components on a circuit board). The light sources or the circuit board with the light sources mounted thereon are mounted on a support element, which may be, for example, part of a heat sink or in turn mounted on such. The heat sink may emit heat generated during the operation of the light sources to the environment and thus provides a thermal relief of the light sources and the entire light module, in which an optical array is included with the attachment optics.

When using the attachment optics or an optical array composed of a plurality of attachment optics in a lighting device of a motor vehicle, these are preferably part of a light module of the illumination device. The light module can be designed to generate any light distribution. When used in a headlight, the light module can be designed, for example, to produce a low beam or a high beam function. When used in a front light, the light module can, for example, be designed to realize a daytime running light, standing, limiting or position light, flashing light or fog light function. When used in a rear light, the module can be designed to generate a taillight, brake light, reversing light or flashing light function. When used in a side light, the light module can be designed to realize a side marker or flashing light function. Of course, the light module can also be designed such that it generates only a part of the desired light distribution and the desired light distribution results only by superimposing the partial light distribution generated by the light module with one or more other partial light distribution.

The effect of the optical attachment according to the invention that the main exit direction of the light beam extends at an angle to the main emission of the at least one of the optical attachment associated light, can be achieved within certain limits by varying the shape and / or orientation of the light entry surfaces and / or light exit surfaces of the optical attachment , Here, however, it must be taken into account that the variation of the shape and / or orientation of the exit surfaces of the attachment optics does not lead to a total reflection of the light actually intended to pass through the surfaces, which would lead to a significant deterioration of the efficiency of the attachment optics. In order to reduce or even completely avoid the effect of an undesired total reflection of the light at the light exit surfaces, at least one of the totally reflecting lateral boundary surfaces of the attachment optics should be in shape and / or orientation relative to an attachment optics, in which the main exit direction is parallel to a main emission direction of the associated optics Light source or light source group runs, be varied accordingly.

An important aspect of the present invention is that with the attachment optics according to the invention, an optical array can be formed, which may be formed in one piece or in several parts. Each intent optics of the array is associated with at least one light source. The attachment optics or the array consist of a transparent dielectric, e.g. made of a transparent plastic or glass. In each of the optical systems of the invention an optically array, the total reflecting interfaces and the refracting light entrance or light exit surfaces direct the light mainly in a direction unequal to the main emission of the LEDs associated with the optical attachment, so that a single light distribution with a maximum of illuminance arises, the optical Axis of the optical head associated optics is shifted. Thus, in contrast to the lens array known from WO 02/33449 A2, each of the optical systems of an optical array according to the invention has a different optical axis. The light intensity of the light coupled out of the optical attachment according to the invention increases starting from a central plane intersecting the optical axis only in one direction and not in each direction, as is the case, for example, in the case of the optical attachment known from DE 10 2009 021 182 A1.

In the context of the present invention, there is talk of several total reflecting interfaces of the attachment optics. Of course, this formulation also encompasses several sections of a single total reflecting interface, as they are, for example, in the case of an attachment optic with a round or oval cross section with a circumferential interface. Considering such an optical attachment in a longitudinal section which comprises an optical axis, the interface can be divided into an upper section and a lower section by means of a further longitudinal section perpendicular to the longitudinal section.

It is particularly advantageous if, due to the non-rotationally symmetrical design of the totally reflecting lateral interfaces, i. the upper section of the interface with respect to the further longitudinal section is designed differently than the lower section, and a prismatic effect of the light entry and / or exit surfaces two measures (refraction and total reflection) are used in combination with each other for deflecting the light. The combination of both measures makes it possible to combine a strong light deflection with a high light efficiency of the front optics. If e.g. a totally reflecting interface designed so that no average deflection of the light from the optical axis of the light source takes place through them, then a deflection is possible only by the prismatic effect of the light exit surface. This prismatic effect is e.g. achieved by tilting the light exit surface with respect to a surface perpendicular to the optical axis of the light source. As the tilt angle increases, the Fresnel reflections on that surface also increase until even total reflections occur. The light losses thus increase noticeably with increasing light deflection. However, if already the totally reflecting interfaces and / or the light entry surfaces are used to achieve a first deflection of the light beams, the light exit surface must be tilted less to achieve a given deflection, which reduces the reflection losses at this surface. Thus, by exploiting the totally reflecting properties of the boundary surfaces and / or the refractive properties of the light entry surfaces, a higher light efficiency of the optics can be achieved with the same deflection achieved. Alternatively, with the same light efficiency, a larger deflection angle can be achieved.

In this sense, it is proposed according to an advantageous development of the invention that considered in a longitudinal section through the optical attachment, the at least one interface on one side of the attachment optics compared to a conventional optical attachment, in which the main exit direction of the light beam parallel to the main emission of the at least one light source runs, is varied such that light rays of the light which has entered the optical attachment meet steeper on the at least one varied interface. In other words, a section of the interface lying above the further longitudinal section with respect to the further longitudinal section is compared to a conventional front optical system in which the main exit direction of the light beam is parallel (or congruent) to the main emission direction of the at least one light source varies such that light rays of the light entered into the attachment optics strike steeper on the at least one varied portion of the interface. As a result, the light rays incident on the upper portion of the interface are reflected more downward.

Alternatively or additionally, it is proposed that viewed in the longitudinal section through the attachment optics at least one further interface on one of the varied interface opposite side of the attachment optics in comparison to a conventional intent optics, in which the main exit direction of the light beam is parallel to the main emission of at least one light source , is varied such that light rays of the light which has entered the optical system strike the at least one further varied boundary surface more flatly. In other words, a relative to the further longitudinal section through the optical attachment below the further longitudinal section lying portion of the interface compared to a conventional intent optics, in which the main exit direction of the light beam parallel (or congruent) to the main emission of the at least one light source, so varies such that light rays of the light that has entered the optical attachment meet more flatly with the at least one further varied portion of the interface. As a result, the light rays impinging on the lower portion of the interface are reflected less strongly upwards or possibly even downwards.

The light sources or light source groups assigned to the individual optical head units of an optical array of a light module are preferably individually and separately controllable. The driving of the light sources also includes dimming, i. an operation with reduced energy. This makes it possible that the light module also generates an adaptive light distribution, which depends on a driving condition of the motor vehicle (eg the speed, a steering angle, a yaw rate, etc.) and / or environmental conditions (eg outside temperature, presence and / or kind a precipitate) and / or dynamically varied from the road condition.

The attachment optics preferably serve as primary optics of a light module. The primary optics serve to bundle and direct the light emitted by the light sources. The light emitted by the primary optics can be used either directly or indirectly, for example after passing through at least one secondary optic (for example a projection or condenser lens), to produce the desired light distribution in front of the motor vehicle or a part thereof.

It is conceivable that between the primary optics and the at least one secondary optics, a diaphragm arrangement is arranged for shading at least a part of the light emitted by the primary optics. The at least one secondary optics can project an edge of the diaphragm arrangement as a light-dark boundary of the resulting light distribution onto the roadway. The diaphragm edge of the diaphragm arrangement is preferably located in a focal point or a focal plane of the projection lens. The diaphragm arrangement may extend in a horizontal plane, wherein the horizontal plane preferably comprises the optical axis of the projection lens. However, it is also conceivable that the auxiliary optics and the remaining light module are designed such that a dimmed light distribution can also be generated without diaphragm arrangement, in which case can be dispensed with a diaphragm arrangement for generating the light-dark boundary.

Further features and advantages of the present invention will become apparent from the following description and the accompanying drawings. It is understood that the features mentioned above and those yet to be explained below can be used not only in the combination described and shown in the figures, but also in any other combinations or alone, without departing from the scope of the present invention. Preferred embodiments of the invention are illustrated in the figures and will be explained in more detail in the following description. Show it:

Figure 1 is a schematic representation of a lighting device of a motor vehicle;

FIG. 2 shows a perspective view of part of a light module according to the invention of a lighting device;

Figure 3 is a plan view of a light-emitting diode array of a light module of a lighting device;

FIG. 4 shows a single optical attachment according to the invention of a light module of a lighting device;

FIG. 5 shows on the left a screen with a light distribution generated by a conventional, rotationally symmetrical optical attachment and on the right a screen with a light distribution generated by an optical attachment according to the invention;

Figure 6 is a side view of part of a light module according to the invention;

FIG. 7 a side view of a light module according to the invention of a lighting device of a motor vehicle; and

8 shows an inventive light module of a lighting device of a motor vehicle in a side view to produce a dimmed light distribution.

FIG. 1 shows a lighting device 10 of a motor vehicle designed as a headlight in a perspective view. The illumination device 10 preferably comprises a housing 12 made of plastic, in which in the illustrated embodiment two light modules 14, 14 'are arranged for generating arbitrary light distributions (for example low beam, high beam, fog light, adaptive or dynamic light distributions, etc.). Of course, the illumination device 10 may also have less or more than the illustrated light modules 14, 14 '. Furthermore, the illumination device 10, in addition to the light modules 14, 14 'also light modules (not shown) include, for example, are used to generate flashing light, daytime running lights, position light, etc. A formed in the light exit direction 16 in the housing 12 light exit opening is closed with a translucent cover 18 made of glass or plastic, to prevent the ingress of dirt and / or moisture. The cover 18 may be at least partially equipped with optically effective profiles, for example. In the form of cylindrical lenses and / or prisms, for scattering the light passing through (so-called. Lens). The cover 18 can also be designed as a so-called. Clear disc without optically effective profiles.

At least one of the light modules 14, 14 'is designed as a light module according to the invention, which will be described in detail below. The other light module can be designed to produce low beam, high beam or any other light distribution or only parts of these light distributions (eg a low beam base light, a high beam base light, a low beam spot, a high beam spot, etc.). The other light module can be configured in any desired manner. If the other light module is designed, for example, as a reflection module, it comprises at least one light source (not shown) for emitting light, which, for example, comprises an incandescent, halogen or gas discharge lamp or at least one semiconductor light source, in particular an LED. Further, the other light module may have a primary optic (e.g., in the form of a reflector or a transparent optics facing optics) for focusing the emitted light. The bundled light reaches the area in front of the vehicle, at least partially on the roadway, to produce the desired light distribution. If a dimmed light distribution is to be generated, the primary optics can be designed accordingly and / or a corresponding diaphragm arrangement can be arranged in the beam path. If the other light module is designed as a projection module, the focused light is projected by at least one secondary optics in front of the vehicle to produce the desired light distribution. The secondary optics may be formed as a projection or condenser lens or as a reflector. To produce a dimmed light distribution, a diaphragm arrangement can be arranged between the primary and the secondary optics, which shadows a part of the collimated light.

A part of a light module according to the invention is shown in a perspective view in FIG. The light module is designated by reference numerals 14, 14 ', since each or both light modules 14, 14' of the illumination device 10 from FIG. 1 could be designed as a light module according to the invention. The light module 14, 14 'comprises an optical array 26, which comprises a plurality of attachment optics 28 according to the invention. The attachment optics 28 or the optical array 26 form a primary optics of the light module 14, 14 'for focusing the light emitted by the light sources. Each of the attachment optics 28 is associated with at least one light source, which is preferably designed as a semiconductor light source, in particular as a light-emitting diode (LED).

As shown by way of example in FIG. 3, the light sources 22 embodied as light-emitting diodes in this example can be arranged on a flat, plate-shaped carrier element 24, for example a printed circuit board, and together form an LED array 20. Of course, it is also conceivable that the Light-emitting diodes 22 are arranged individually or in groups on a plurality of carrier elements 24. Furthermore, the carrier element 24 may also be designed differently than shown in FIG. 3, for example, having a round, oval or triangular shape. The light-emitting diodes 22 can be individually or group-controlled, so that they can be activated, deactivated or dimmed individually or in groups.

Irrespective of the configuration of the carrier element 24, the light emitting diodes 22 are configured in such a way and arranged in the light module 14, 14 'that their main emission directions 32 extend substantially parallel to one another out of the plane of the drawing. The main radiation directions 32 preferably extend perpendicular to the plane of the drawing of FIG. 3 or to the plane extent of the carrier element 24. In the exemplary embodiment illustrated, the light emitting diodes 22 are arranged on the carrier element 24 in a matrix-like manner in two lines. The arrangement of the light-emitting diodes 22 on the carrier element 24, however, may differ in individual cases from the illustrated form. The light-emitting diodes 22 are preferably arranged on the carrier element 24 in such a way that, when the LED array 20 is mounted in the ready-to-use state in the

light module

14, 14, at least one LED 22 is assigned to each of the auxiliary optics 28. Accordingly, in the case of a single-line optical array 26 with a plurality of intent optics 28 arranged next to one another only in one row, only one-line arrangement of the light-emitting diodes 22 on the carrier element 24 would be possible.

It can be seen from FIG. 2 that the LED array 20 or the carrier element 24 on which the light-emitting diodes 22 are fastened and electrically contacted are arranged between the optical array 26 and a heat sink 30 of the light module 14, 14 '. The optical array 26 or the attachment optics 28 are designed in such a way that the main exit directions 42 of the individual light bundles emerging from the individual attachment optics 28 extend at an angle to the main emission directions 32 of the light sources 22 assigned to the attachment optics 28. In the case of the light module 14, 14 'according to the invention, it is thus possible to position, align, fasten and contact the light-emitting diodes 22 simply, quickly, automatically and inexpensively on a flat carrier element 24. An alignment or deflection of the individual light bundles in a certain direction, which is necessary for generating a desired resulting light distribution of the light module 14, 14 ', is achieved solely by the special configuration of the attachment optics 28. Aligning or redirecting the individual light bundles may be necessary in order, for example, to set a light-dark boundary of the resulting light distribution or by certain minimum or maximum values of the illuminance at specific, preferably legally defined and predetermined points of the light distribution, for example certain overhead values above a light-dark boundary at a dimmed light distribution to realize. The lens array 26 thus represents in the light module 14 a primary optics for bundling and shaping the light emitted by the light emitting diodes 22.

The optical attachment 28 is made of a transparent dielectric in the form of a translucent material, for example glass or plastic. It is asymmetrical, in particular not rotationally symmetrical to a longitudinal axis of the attachment optics 28, formed. When mounted in the light module 14, 14 'in the ready state LEDs 22 and attachment optics 28, the auxiliary optics 28 are formed asymmetrically to the main radiation directions 32 of the LEDs 22. The orientations of the light bundles from the individual attachment optics 28 of the optical array 26 are different, so that in the illustrated embodiment, the main exit directions 42 of the attachment optics 28 converge at an imaginary point or a three-dimensional point area or a point cloud behind the heat sink 30. Of course, it would also be conceivable that the attachment optics 28 are designed and aligned such that the main exit directions 42 converge in a point or a point cloud in front of the optical array 26. Furthermore, not all auxiliary optics 28 of the optical array 26 need to be designed as optical attachments according to the invention. It is quite conceivable that one or more of the attachment optics are designed as conventional, for example rotationally symmetrical, attachment optics. Such an embodiment is shown in FIG.

FIG. 4 shows, by way of example, the configuration of an asymmetric optical attachment 28 according to the invention in detail. The attachment optics 28 serves for bundling the light emitted by the attachment optics 28 and at least one light source 22. The attachment optics 28 has at least one light entry surface 36, by which at least part of the light emitted by the at least one light source 22 is coupled into the attachment optics 28. The light entry surface 36 is formed asymmetrically in the illustrated embodiment. Furthermore, the attachment optics 28 comprises totally reflecting interfaces 34, on which at least part of the coupled-in light is totally reflected. Finally, the attachment optics 28 comprises at least one light exit surface 38, by which at least part of the coupled-in light, optionally after at least one total reflection at one of the interfaces 34, is coupled out of the attachment optics 28.

A first light entry surface 36 'may be curved, so that it can deflect light rays passing through it in the manner of a lens. In the illustrated embodiment, the surface 36 'is convexly curved, so that light rays passing therethrough are bundled in the manner of a converging lens. This curved surface 36 'is also inclined in the illustrated longitudinal section through the optical attachment 28. Also, the light exit surface 38 may be curved at least partially, so that they can deflect light rays passing therethrough in the manner of a lens. In the illustrated embodiment, the surface 38 is convexly curved, so that light rays passing therethrough are concentrated in the manner of a converging lens. Also, the curved exit surface 38 is inclined in the illustrated longitudinal section through the attachment optics 28 and in a direction opposite to the direction of inclination of the first entrance surface 36 '.

A portion of the light emitted by the light source 22 is focused by refraction when passing through the central light entry surface 36 'and / or during passage through a central region of the light exit surface 38 (beam path 40'). The bundled in this way light thus passes without total reflection at the interfaces 34 through the attachment optics 28. Another part of the light emitted from the light source 22 is coupled via the lateral entrance surfaces 36 "in the optical attachment 28, largely reflected at the interfaces 34 and over an outer edge region of the exit surface 38 coupled out (beam path 40 "). The light is focused by refraction when passing through the light entrance surface 36 ", by total reflection at one of the interfaces 34 and / or by refraction when passing through the light exit surface 38. The light emitted by the light emitting diode 22 is thus subdivided into two parts pass through the optical attachment 28 in different ways and are bundled in different ways.

The attachment optics 28 has an asymmetrical shape of the light outcoupling surface 38 and the interface 34 with respect to the main emission direction 32 of its associated light-emitting diode 22. Of course, it would be conceivable to design asymmetrical only the boundary surfaces 34 and to leave the decoupling surface 38 symmetrical as in the rotationally symmetrical attachment optics known from the prior art.

In the longitudinal section through the attachment optics 28 shown in FIG. 4, it can easily be seen that at least one boundary surface 34 on one side of the attachment optics 28, namely the upper longitudinal interface 34 with respect to a further longitudinal cut comprising the main emission direction 32 of the light emitting diode 22 and perpendicular to the plane of the drawing ', as compared to a conventional symmetrical attachment optics, in which the main exit direction 42 of the light beam is parallel to the main emission direction 32 of the light source 22, is varied such that light rays of the light coupled into the optical attachment 28 light meet steeper on the at least one varied interface 34' , As a result, the light rays 40 "at the interface 34 'are also totally steeper and thus deflected more strongly downwards.

Furthermore, it can be seen that viewed in the illustrated longitudinal section through the attachment optics 28, at least one further interface 34, which is preferably arranged on one of the first varied interface 34 'opposite side of the attachment optics 28, namely the lower boundary surface 34 with respect to the further longitudinal section ", As compared to a conventional symmetrical attachment optics, in which the main exit direction 42 of the light beam is parallel to the main emission direction 32 of the light source 22, is varied such that light rays 40" of the coupled into the optical attachment 28 light shallower on the at least one further varied interface 34 "meet. As a result, the light beams 40 "are also totally flat at the interface 34" and thus less deflected, i. they come down directed out of the attachment optics 28.

In the illustrated optical attachment 28, the light exit surface 38 is additionally designed such that the angle α between the main exit direction 42 of the light beam and the main emission direction 32 of the light source 22 in comparison to a conventional symmetrical attachment optics (28 'in Figure 6) with a light exit surface 38, in which the main exit direction 42 of the light beam runs parallel or even congruent to the main emission direction 32 of the at least one light source 22, increases. The light exit surface 38 is thus inclined and / or curved in the illustrated embodiment of the optical attachment 28 according to the invention so that the light rays passing through experienced an additional deflection down. It is particularly preferred that the light exit surface 38 of the attachment optics 28 is varied in such a way that light rays emerging from the attachment optics 28 are flatter compared to a conventional intent optics, in which the main exit direction 42 of the light bundle runs parallel to the main emission direction 32 of the at least one light source 22 the at least one varied light exit surface 38 meet.

Similarly, one or more of the light entry surfaces 36 may be varied. Thus, in FIG. 4, the inclination of the curved entrance surface 36 'is changed such that the angle α of the main exit direction 42 of the light bundle with respect to the main emission direction 32 of the light source 22 with a light entry surface 38 compared to a conventional symmetrical attachment optics 28' in FIG , in which the main exit direction 42 of the light beam runs parallel to the main emission direction 32 of the at least one light source 22, is increased. The same could also be done with the lateral entry surfaces 36 ", so that the main exit direction 42 of the light bundle is tilted further downwards. In particular, the inclination of the upper entrance surface 36 "could be varied such that the light rays 40" impinge on the upper interface 34 'at a steeper angle. Similarly, the inclination of the lower entrance surface 36 "could be varied such that the light rays 40" impinge on the lower boundary surface 34 "at a shallower angle.

FIG. 5 shows on the left a light distribution realized with a conventional symmetrical attachment optics and on the right a light distribution generated by the asymmetrically designed attachment optics 28 according to the invention. In the light distribution, areas of the same illuminance are illustrated by so-called isolux lines 45. The illuminance preferably decreases from the inside to the outside, in which case the highest illuminance values lie in the center of the light distribution. Of course, any other intensity distribution within the light distribution is conceivable. A focus of the light distribution in the main exit direction 42 is designated in FIG. 5 by the reference numeral 44. In FIG. 5, on the left, the center of gravity 44 of the light distribution in the main exit direction 42 lies approximately at the intersection of the main emission direction 32 of the LEDs 22 with the illustrated xy plane. That is, the conventional symmetrical attachment optics, although bundles the passing light, but does not cause deflection of the light in a deviating from the main direction of emission 32 of the LEDs 22 direction.

On the right in FIG. 5, the shift of the light distribution to the right, realized with the optical attachment 28 according to the invention, is shown. For this purpose, an intent optics 28 from FIG. 4 rotated by 90 ° about an axis running parallel to the main emission direction 32 is used so that the light bundle is not deflected downwards, as shown in FIG. 4, but to the right. The attachment optics 28 causes a shift of the center of gravity 44 in the main exit direction 42 of the light distribution to the right. The intensity distribution within the light distribution preferably remains largely unchanged, which becomes clear on the basis of the substantially same course of the isolux lines 45 without displacement (left in FIG. 5) and with displacement to the right (on the right in FIG. 5).

In FIG. 5, a shift of the center of gravity 44 on the x-axis to the right is assumed. However, by a rotation of the attachment optics 28 about an axis parallel to the main emission direction 32 by an arbitrary rotation angle, the displaced center of gravity 44 can be aligned in any direction, ie at an angle of 360 ° relative to the illustrated x-axis. By how much the light beam is deflected, is determined by the configuration of the optical attachment 28, in particular the boundary surfaces 34, the light entry surfaces 36 and the light exit surfaces 38.

FIG. 6 shows a detailed section of a lens array 26 according to the invention in a side view. In FIG. 6, three light-emitting diodes 22 are arranged on the carrier element 24 which has just been formed. Each light emitting diode 22 is associated with an attachment optics 28 or 28 '. The attachment optics 28 shown in FIG. 6 at the top and at the bottom are asymmetrically designed in accordance with the invention and correspond in structure and function to the description of FIGS. 4 and 5. However, both attachment optics 28 are arranged at approximately 180 ° to each other on the carrier element 24 that the main exit directions 42 of the attachment optics 28 merge in a common intersection 48.

The arranged in Figure 6 in the middle attachment optics 28 'is in contrast rotationally symmetrical, that is, the Hauptabstrahlrichtung 32 of the light emitting diode 22, which is the optics 28' associated, and the main exit direction 42 of the attachment optics 28 'coincide. The attachment optics 28 'or their associated light-emitting diode 22 is positioned on the carrier element 24 such that the coincident main emission direction 32 and main exit direction 42 pass through the intersection point 48 formed by the main emission directions 42 of the two other attachment optics 28. The middle attachment optics 28 'corresponds to a conventional symmetrical attachment optics. The attachment optics 28 and 28 'are thus arranged and aligned such that the three main exit directions 42 converge in the common intersection point 48.

The optical array 26 may also have more than the illustrated three front optics 28, 28 '. These can be arranged in one row, so that a linear optical array 26 results. However, it would also be conceivable that the auxiliary optics 28, 28 'are arranged in a matrix-like manner in a plurality of rows and columns. When more than three attachment optics 28, 28 'are used in the array 26, at least two attachment optics 28, 28' can always be combined into a group whose main exit directions 42 intersect at a common intersection point 48. It is possible, but not essential, for the intersections 48 of the different optical groups to be identical. In the embodiment shown in FIG. 6, the individual attachment optics 28, 28 'of the optical array 26 are formed as separate, discrete elements and become relative only by the attachment on the common carrier element 24 and / or the common heat sink 30 in the predetermined position and position held each other.

FIG. 7 shows a light module 14, 14 'of the motor vehicle headlight 10 according to the invention. The light module 14, 14' has the heat sink 30 on which the carrier element 24 that has just been formed is arranged and fastened. On the support member 24, three LEDs 22 are arranged and electrically contacted, which is associated with a one-piece lens array 26. The one-piece lens array 26 summarizes the functions of three discrete attachment optics, such as the three face optics 28, 28 'of Figure 6, and is formed as an integral unit. For this purpose, material bridges are provided between the discrete attachment optics 28, 28 'from FIG. 6, which preferably have no optically effective properties. The function of the one-piece lens array 26 is comparable to that of the multipart lens array 26. Of course, in the light module 14, only a part of the attachment optics 28, 28 'can be combined to form the one-piece lens array 26, or a plurality of lens arrays 26 each having a plurality of attachment optics 28, 28' can be arranged in the light module 14.

In addition, in the beam path of the light bundled by the lens array 26, a secondary optic embodied as a converging lens 50 is arranged in the light module 14. The converging lens 50 serves to expand the light beam generated by the lens array 26 and to image a desired, legally prescribed light distribution, for example a low-beam or high-beam distribution, in front of the vehicle. The common intersection point 48 lies in the region of an optical axis 52 of the converging lens 50 between the primary optics 26 and the secondary optics 50, preferably at the focal point of the secondary optics 50.

In a further embodiment, the light emitting diodes 22 can also be controlled individually, preferably individually dimmable. As a result, the light distribution generated by the light module 14, 14 'can be varied both with regard to the horizontal and vertical extent of the light distribution and with regard to the intensity distribution within the light distribution. A dimming of the light-emitting diodes 22 furthermore makes it possible for the light module 14, 14 'to be able to generate a daytime running light distribution in addition to a high beam distribution and thus to operate as a light module in the motor vehicle headlight 10. In this way, a daytime running light function can be realized without an additional lighting module.

It is also possible that the lens array 26 according to the invention is used in the rear region of the motor vehicle, for example for generating a tail light and / or a brake light or a flashing light and / or a brake light.

FIG. 8 shows an inventive light module 14, 14 'of the motor vehicle headlight 10 for producing a dimmed light distribution. In addition to the representation from FIG. 7, the light module 14, 14 'has an aperture arrangement 54 arranged horizontally and parallel to an optical axis 52 of the module 14, 14'. Of course, the diaphragm arrangement 54 can also be arranged and aligned in any other way. A front diaphragm edge 55 of the diaphragm arrangement 54 is preferably positioned in the region of the collecting point 48 of the main exit directions 42 of the auxiliary optics 28, 28 'of the array 26. The shutter assembly 54 shields a portion of the light focused by the lens array 26, the shutter edge 55 being projected by the condenser lens 50 as a light / dark boundary of the dimmed light distribution onto the road ahead of the vehicle.

However, it is also possible that the attachment optics 28, 28 'in the lens array 26 according to the invention are designed such that even without a diaphragm arrangement, such as the diaphragm assembly 54, solely by the design of the light coupling surfaces 36 and / or the light outcoupling surfaces 38 and the total reflecting interfaces 34 a dimmed light distribution can be generated. In this case, the diaphragm arrangement 54 can be dispensed with.

Claims

Auxiliary optics (28) for bundling light of at least one light source (22) associated with the optical attachment (28), wherein the optical attachment (28) consists of a transparent material and light entry surfaces (36) through which at least a portion of the at least one light source (28) 22) emitted light into the optical attachment (28), totally reflecting boundary surfaces (34) which at least partially reflect the part of the incoming light, and light exit surfaces (38) through which at least a portion of the incoming light, optionally after at least one total reflection at one of Boundary surfaces (34) from the attachment optics (28) emerges, wherein the bundling of the light of the at least one light source (22) by refraction when passing through one of the light entry surfaces (36) and / or passing through one of the light exit surfaces (38) and / or by total reflection at one of the interfaces (34) takes place, wherein the attachment optics (28) with respect to a Having the main emission direction (32) of the at least one light source (22) standing in a reference main exit direction (42) of the focused light, characterized in that at least one of the boundary surfaces (34) of the adapter lens (28) is designed such that the main exit direction (42) of the light beam at an angle to the main emission direction (32) of the at least one light source (22).
Attachment optics (28) according to claim 1, characterized in that viewed in a longitudinal section through the attachment optics (28), the at least one interface (34 ') on one side of the attachment optics (28) compared to a conventional attachment optics (28') at in that the main exit direction (42) of the light bundle runs parallel to the main emission direction (32) of the at least one light source (22) is varied in such a way that light beams of the light entered into the auxiliary optics (28, 28 ') steeper to the at least one varied interface ( 34 ') meet.
Attachment optics (28, 28 ') according to claim 2, characterized in that viewed in the longitudinal section through the attachment optics (28) at least one further interface (34 ") on one of the varied interface (34') opposite side of the attachment optics (28). compared to a conventional optical attachment (28 '), in which the main exit direction (42) of the light beam parallel to the main emission direction (32) of the at least one light source (22) varies, is varied so that light rays of the into the optical attachment (28) occurred Flatten light on the at least one further varied interface (34 ") meet.
Attachment optics (28) according to one of claims 1 to 3, characterized in that at least one of the light exit surfaces (38) of the attachment optics (28) is formed such that the angle (α) between the main exit direction (42) of the light beam and the main emission direction (32) of the at least one light source (22) compared to a conventional optical attachment (28 ') with a light exit surface in which the main exit direction (42) of the light beam parallel to the main emission direction (32) of the at least one light source (22) increases ,
Front optics (28) according to claim 4, characterized in that the at least one light exit surface (38) of the attachment optics (28) in comparison to a conventional attachment optics (28 '), in which the main exit direction (42) of the light beam parallel to the main emission direction (32 ) of the at least one light source (22), is varied in such a way that light rays emerging from the optical attachment (28) strike the at least one varied light exit surface (38) more flatly.
Front optics (28) according to one of claims 1 to 5, characterized in that at least one of the light entry surfaces (36 ', 36 ") of the attachment optics (28) is formed such that the angle (α) between the main exit direction (42) of Light beam and the main emission direction (32) of the at least one light source (22) compared to a conventional optical attachment (28 ') having a light exit surface, wherein the main exit direction (42) of the light beam parallel to the main emission direction (32) of the at least one light source (22 ), increases.
Optical array (26) comprising a plurality of juxtaposed, one above the other and / or offset from each other attachment optics (28, 28 ') of a transparent material, wherein the optical array (26) for converging light from the auxiliary optics (28, 28') associated light sources (22 ), characterized in that the optical array (26) has attachment optics (28) according to at least one of the preceding claims.
Optics array (26) according to claim 7, characterized in that a plurality of adjacent optical attachments (28, 28 ') are combined to form an optical unit.
Optics array (26) according to claim 7 or 8, characterized in that at least two of the attachment optics (28, 28 ') are formed, arranged and aligned so that they from their respective associated light sources (22), the Hauptabstrahlrichtungen (32). run parallel to each other, bundle emitted light to light bundles with different main exit directions (42).
Optics array (26) according to claim 7 or 8, characterized in that the main exit directions (42) of the light bundles converge in a common three-dimensional intersection region (48).
Light module (14, 14 ') of a lighting device (10) of a motor vehicle, comprising

- More on a planar support member (24) arranged light sources (22) for emitting light with substantially mutually parallel Hauptabstrahlrichtungen (32) and

- An optical array (26) comprising a plurality of side by side, one above the other and / or offset from each other arranged Vorsatzoptiken (28, 28 ') of a transparent material, wherein the optical array (26) for converging light from the auxiliary optics (28, 28') associated light sources (22) is formed, characterized in that the optical array (26) is designed according to one of claims 7 to 10.
Light module (14, 14 ') according to claim 11, characterized in that the auxiliary optics (28, 28') serve as the primary optics of the light module (14, 14 ') and that the light module (14, 14') at least one arranged in the beam path secondary optics (50) for projecting the light bundles generated by the primary optics (28, 28 ') in front of the motor vehicle.
Light module (14, 14 ') according to claim 12, characterized in that the at least one secondary optics comprises a projection lens (50).
Light module (14, 14 ') according to claim 12 or 13, characterized in that the light module (14, 14') between the primary optics (28, 28 ') and the at least one secondary optics (50) arranged aperture arrangement (54), wherein the at least one secondary optics (50) images an edge (55) of the diaphragm arrangement (54) as a light / dark boundary of a dimmed light distribution generated in front of the motor vehicle on the roadway.
Light module (14, 14 ') according to claim 14, characterized in that the diaphragm arrangement (54) is arranged horizontally in the light module (14, 14') and the at least one secondary optic (50) has a front edge (55) of the diaphragm arrangement (54 ) as the bright / dark border of light distribution on the road surface.