DE102020110725A1 - Automotive light module - Google Patents

Abstract

A motor vehicle light module is presented with an optical element that has a light entry surface and with at least two light modules, with which only part of the light entry surface is illuminated in each case. The motor vehicle light module is characterized in that parts of the light entry surface that are illuminated by two closest light modules directly adjoin each other without overlapping and that the two light modules are set up to generate light bundles, the light rays of which hit an imaginary smooth surface that extends between the Light modules on one side and the light entry surface on the other side extends, impinge perpendicularly and that the light entry surface is a tangential cylindrical surface.

Description

The present invention relates to a motor vehicle light module according to the preamble of claim 1. Such a light module is for example from the US 2016/0091653 A1 known and has a light-refracting optical element which has a light entry surface and at least two light modules, with each of which a light beam can be emitted, which illuminates part of the light entry surface and does not illuminate a complementary part of the light entry surface.

The light exit surfaces of motor vehicle lighting modules are nowadays taking on complex shapes and more and more often they should also have animatable appearances. The motor vehicle light modules are used, for example, for greeting animations or also while driving as direction indicators that convey an impression of movement. The light exit surface of the motor vehicle lamp modules used for this purpose is, for example, divided into sub-areas that are different from one another and that can be activated independently of one another, i.e. switched to light-emitting (digital on / off) or whose brightness can be continuously controlled. The transition between two sub-areas should not be visible when all sub-areas or at least two sub-areas that are next to each other are activated.

A division of the light exit area into partial areas may also be necessary in the case of static motor vehicle light modules due to the length of the area to be illuminated and the available installation space. In this case, too, the separation of the sub-areas should not be visible.

Against this background, the object of the invention consists in specifying a motor vehicle light module of the type mentioned at the outset, in which a separation between two next-to-one another partial areas that are activated is not visible.

This object is achieved with the features of claim 1. The present invention differs from the prior art mentioned at the beginning by the characterizing features of claim 1. These provide that parts of the light entry surface illuminated by two nearest adjacent light modules are directly adjacent to one another without overlapping and that the at least two light modules are set up to generate light bundles, the light rays of which strike an imaginary smooth surface that extends between the light modules on one side and the light entry surface on the other side, and that the light entry surface is a freeform surface. In the present invention, a smooth surface is understood to be a tangent-continuous surface, that is to say a surface which can be continuously differentiated at least once at each point.

A preferred embodiment is characterized in that the optical element is a light guide plate with equidistantly opposite broad sides, the light entry surface and the light exit surface each being a narrow side of the light guide plate.

It is also preferred that each light module has a light source and a smooth reflective surface which can be illuminated with light emanating from the light source.

It is further preferred that the optical element has a light exit surface and that each light module and the light entry surface are matched to one another in such a way that a spatially constant luminance results on the light exit surface when the light sources are switched on.

Another preferred embodiment is characterized in that the light exit surface is provided with cushion optics or steps with which a signal light distribution can be generated.

It is also preferred that the reflective surfaces are designed and arranged such that their reflective surfaces intersect.

It is further preferred that each of the reflection surfaces has an optical axis and that each optical axis perpendicularly penetrates the imaginary surface.

Another preferred embodiment is characterized in that the light sources of two light modules next to each other lie symmetrically to a surface which is perpendicular to a connecting axis of the light sources running through the center of the light sources.

It is also preferred that the light modules are designed in such a way that when the light sources are switched on, there is a steady course of the luminance transversely to the line of intersection between two reflective surfaces.

It is further preferred that the light sources can be controlled individually.

Further advantages emerge from the following description, the drawings and the subclaims. It goes without saying that the features mentioned above and those yet to be explained below not only in the respectively specified combination, but also in others Combinations or can be used alone without departing from the scope of the present invention.

• 1 eine Schnittdarstellung einer Kraftfahrzeugbeleuchtungseinrichtung mit einem Ausführungsbeispiel eines erfindungsgemäßen Kraftfahrzeugleuchtenmoduls;
• 2 eine perspektivische Darstellung der Anordnung eines drei Kammern aufweisenden Reflektors und eines lichtbrechenden optischen Elements des Kraftfahrzeugleuchtenmoduls aus der 1; und
• 3 eine Anordnung des drei Kammern aufweisenden Reflektors und eines lichtbrechenden optischen Elements des Kraftfahrzeugleuchtenmoduls aus den 1 und 2 zusammen mit einem zum den drei Kammern alternativen Einkammerreflektors.

Embodiments of the invention are shown in the drawings and are explained in more detail in the following description. Show, each in schematic form:

• 1 a sectional view of a motor vehicle lighting device with an embodiment of a motor vehicle light module according to the invention;
• 2 a perspective view of the arrangement of a reflector having three chambers and a light-refracting optical element of the motor vehicle light module from FIG 1 ; and
• 3 an arrangement of the three-chamber reflector and a light-refracting optical element of the motor vehicle light module from the 1 and 2 together with a single-chamber reflector as an alternative to the three chambers.

In detail, the 1 a motor vehicle lighting device 10 with a housing 12th , whose light exit opening from a transparent cover plate 14th is covered. Inside the case 12th is a motor vehicle light module 16 arranged. 2 Figure 12 shows an isometric view of the motor vehicle light module 16 . The motor vehicle light module 16 has a refractive optical element 18th on, which is a light entry surface 18.1 and a light exit surface 18.2 having. The refractive optical element 18th is a light guide plate with equidistantly opposite broad sides. Here are the light entry surface 18.1 and the light exit surface 18.2 each one narrow side of the light guide plate. The light entry surface 18.1 comes with from light modules 20.1 until 20.n of the motor vehicle light module 16 outgoing light bundles 22.1 until 22.n illuminated.

The light entry surface 18.1 is a free-form surface, the generating line y of which is perpendicular to the main direction of incidence x of the light bundle 22.1 until 22.n and which is tangent-continuous.

In the 1 and 2 is the number n of the light modules 20.i with equal to 1 to n equal to 3. In general, n can be any number that is greater than or equal to two. Every light module 20.1 preferably each has a light source 24.1 , ..., 24.n and a primary optical element 26.1 , ..., 26.n that forms and deflects a light beam emanating from the light source. In the exemplary embodiment shown here, the primary optical element is a smooth individual reflection surface 27.1 , ..., 27.n which can be illuminated with light emanating from the respective uniquely associated light source.

Any light source 24.1 , ..., 24.n is preferably a semiconductor light source radiating into a half-space, which consists of a single light-emitting diode or an arrangement of light-emitting diodes which can be switched on and off individually or jointly. The switching states of the light-emitting diodes are determined individually or in groups by a control unit 28 controlled. In one embodiment, the light-emitting diodes of the arrangement are set up to emit light of a uniform light color. In an alternative embodiment, first light-emitting diodes of the arrangement are set up to emit light of a first light color, and second light-emitting diodes of the arrangement are set up to emit light of a second light color.

With every light module 20.1 until 20.n is a bundle of light 22.1 until 22.n emittable, which is part of the light entry surface 18.1 of the optical element 18th illuminated and a complementary part of the light entry surface 18.1 of the optical element 18th not illuminated. Parts of the light entry surface of the optical element which are illuminated by two light modules that are next to one another in each case directly adjoin one another, but do not overlap.

That of the switched on light sources 24.1 , ..., 24th n Outgoing light is deflected by the individual reflection surface, which is illuminated with the light from the light source, and parallelized in the direction of the generators y of the light entry surface of the optical element, so that the light is in xy planes (cf. 2 ) spreads in parallel. The light thus spreads in areas that are spanned in parallel by the main direction of propagation x of the light of a light bundle, i.e. the optical axis of a single reflection area, and the generator y.

In addition, the light modules are set up to generate the light bundles in such a way that their light rays hit an imaginary, outer smooth surface 30th that are located between the light modules 20.1 , ..., 20. n on one side and the light entry surface 18.1 of the optical element 18th extends on the other side, impinge perpendicularly. The imaginary, smooth outer surface is not a physically existing surface, but a construction aid surface for the design of the individual reflection surfaces and the light entry surface 18.1 of the optical element 18th .

Each of the individual reflection surfaces has an optical axis or a main emission direction x, which is the imaginary, outer smooth surface 30th pierces vertically. The individual reflection surfaces 27.1 , ..., 27.n light modules next to each other 20.1 , ..., 20.n are designed and arranged so that they intersect. The light sources of two light modules next to each other are symmetrical to a line 32 , in which the individual reflection surfaces of these two light modules intersect.

The individual reflection surfaces of the light modules are thus set up to emit the light of the light sources emanating from them in such a way that this light is perpendicular to the imaginary, outer smooth surface 30th occurs. This creates bundles of light 22.1 , ..., 22.n that are directly adjacent to one another, but do not penetrate one another.

The requirement of perpendicular impingement means in connection with the smoothness of the imaginary, outer smooth surface 30th in particular, that rays of light, which on the imaginary, outer smooth surface 30th impinge at an infinitesimally small distance, are parallel to each other and thus run free of intersections.

This also applies in particular to the edge rays in mutually facing edge surfaces of light bundles that are closest to one another.

These parallel rays of light then strike the light entry surface in parallel 18.1 which is also a smooth surface. This defines the shape of the light bundles and thus also the position of the parts of the light entry surface illuminated by these light bundles. Because of the smoothness of the light entry surface and because of the parallelism and the infinitesimally small spacing of the light rays under consideration, these light rays run (or at least their to the broad sides of the optical element 18th parallel components) also within the refractive optical element 18th (in the plane of the drawing) parallel.

Through the design of the automotive lighting module 16 subsequent shifting of the individual reflection surfaces 27.1 , ..., 27.n in one to the imaginary, outer smooth surface 30th The individual reflection surfaces can be in the vertical direction 27.1 , ..., 27.n of the next adjacent light modules are placed in such a way that they intersect exactly in such a way that each individual reflective surface 27.1 , ..., 27.n , or each light module, exactly a sub-area of the light entry surface 18.1 of the optical element 18th illuminated, whereby the different individual reflection surfaces 27.1 , ..., 27.n illuminated partial areas of the light entry surface of the optical element 18th touch but not overlap.

By joining the individual reflection surfaces thus obtained and arranged in this way 27.1 , ..., 27.n the result is a coherent reflective surface that is optically effective as a whole and is not interrupted by draft bevels or optically inactive walls. This coherent reflection surface can also be provided with relative cushions (cushion optics which only have a scattering effect) in order to compensate for tolerances of the light sources, for example. (You can also design the cushions in such a way that they produce the entire light distribution or produce part of the light distribution).

The optical element 18th shows the light exit surface 18.2 on, and every light module 20.1 , ..., 20.n and the light entry surface 18.1 of the optical element 18th are preferably matched to one another in such a way that they are on the light exit surface 18.2 of the optical element 18th with the light sources switched on 24.1 , ..., 24th n gives a spatially constant luminance.

By moving the individual reflection surfaces 27.1 , ..., 27.n and by moving their focal points with the light sources switched on 24.1 , ..., 24th n a steady course of the luminance of the individual reflection surfaces 27.1 , ..., 27.n at the transition between two adjacent individual reflection surfaces 27.1 , ..., 27.n achieved.

That of the individual reflection surfaces 27.1 , ..., 27.n Outgoing light from the light sources passes through the light entry surface 18.1 into the refractive optical element 18th a. There the light propagates in the from the various individual reflection surfaces 27.1 , ..., 27.n outgoing light bundles to the light exit surface of the optical element, wherein the next adjacent light bundles continue to touch without penetrating each other.

The continuity of the luminance curve at the transition from one light beam to the other light beam is also retained. This is the transition between the sub-areas 34.1 , ... 34.n not recognizable when the light sources are switched on at the same time.

Every light module 20.1 , ..., 20.n illuminated from inside the optical element 18th out a sub-area C of the light exit surface 18.2 . The sub-areas illuminated by the light modules that are next to each other adjoin each other without overlapping. In addition, the illuminance with which each sub-area 34.1 , ... 34.n is illuminated by the light module illuminating it, within each sub-area 34.1 , ... 34.n spatially constant and the same from sub-area to sub-area. This results in a uniformly bright appearance of the luminous light exit surface when the light sources are switched on 18.2 without light or dark transitions on the Limits of the sub-areas 34.1 , ... 34.n the light exit surface 18.2 of the optical element 18th . The light emitting surface 18.2 can with scatter structures 18.3 such as cushion optics or steps, with which that from the light exit surface 18.2 outgoing light is distributed in a signal light distribution.

• Um mit einem einzigen Lichtmodul 40, das einen Reflektor 42 aufweist, ein sinnvolles Maß an Lichtausbeute bei angemessener Leuchtdichte auf der gesamten Reflektorfläche zu erzielen, muss das Aspektverhältnis (Höhe zu Breite) der Lichtaustrittsfläche des Reflektors 42 innerhalb eines begrenzten Wertebereichs liegen, hier bspw. zwischen 1 zu 1,5 und bis zu 1 zu 2. Dabei wird unter der Höhe bei den hier bevorzugt verwendeten Einzelreflexionsflächen in Souffleusenform die Abmessung der Einzelreflexionsfläche in der Hauptabstrahlrichtung der Halbleiterlichtquelle verstanden. Unter der Breite wird hier die Abmessung senkrecht zur Hauptabstrahlrichtung der Halbleiterlichtquelle und senkrecht zur Hauptabstrahlrichtung des Reflektors verstanden.

The division into individually switchable and switchable sub-areas 34.1 , ..., 34.n the light exit surface 18.2 is based on the use of several light sources and light modules. But even if such a division is not necessary, the use of several light modules results in advantages over the use of a single light module with an otherwise unchanged structure of the motor vehicle light module. For example, the required installation depth can be reduced, such as 3 shows:

• To with a single light module 40 that has a reflector 42 has to achieve a reasonable level of light yield with adequate luminance on the entire reflector surface, the aspect ratio (height to width) of the light exit surface of the reflector must be 42 lie within a limited range of values, here for example between 1 to 1.5 and up to 1 to 2. Here, the height of the individual reflective surfaces in prompter form preferably used here is understood to mean the dimensions of the individual reflective surface in the main emission direction of the semiconductor light source. The width is understood here as the dimension perpendicular to the main emission direction of the semiconductor light source and perpendicular to the main emission direction of the reflector.

In the 3 it can be seen that, for example, n = 3 individual reflection surfaces joined together to form a coherent reflection surface 27.1 , ..., 27.n with the same opening angle closer to the light entry surface 18.1 of the optical element 18th can be positioned as a single reflector 42 , which is the light entry surface 18.1 Illuminated with the same opening angle. The several individual reflection surfaces 27.1 , ..., 27.n The invention using it thus has the advantage of a smaller installation depth (depth T is saved). In addition, the greater number of individual reflection surfaces according to the invention has an effect 27.1 , ..., 27.n favorable when larger luminous fluxes are to be generated. With the same light output as a single semiconductor light source, the division of the light output over several semiconductor light sources has the advantage of better heat removal.

When designing the motor vehicle light module, the procedure is as follows: First, the light exit surface 18.2 of the refractive optical element 18th given. The specification is made, for example, so that the light exit surface 18.2 an outer shape of a motor vehicle lighting device 10 , be it a headlight or a rear light, follows.

Then there is an imaginary, smooth inner surface 44 given (compare 2 ) located inside the optical element 18th between the light entry surface 18.1 and the light exit surface 18.2 of the optical element 18th extends transversely to the direction of light propagation. The imaginary inner smooth surface 44 is specified so that on it from the light entry surface 18.1 of the optical element 18th incident light that passes through it vertically from the inside onto the light exit surface 18.2 of the optical element 18th falls, and that their shape is an adjustment of a uniform illuminance of the light exit surface 18.2 favored. This is the case, for example, when a first section of the imaginary inner smooth surface 44 , which is farther from the light exit surface in the direction of light propagation 18.2 of the optical element 18th away is a second section of the imaginary inner smooth surface 44 , is penetrated by a first partial light bundle which has a smaller opening angle than a second partial light bundle which penetrates the second section of the imaginary area.

The luminance distribution visible from the outside, which is located on the light emitting surface 18.2 of the optical element 18th is set by the interaction of the reflector geometry and the light entry surface 18.1 of the optical element 18th set. The imaginary, smooth outer surface 30th is arranged and shaped so that it is of each between the reflective surface and the light entry surface 18.2 of the optical element 18th the incident beam is pierced vertically.

If the imaginary, outer smooth surface 30th is known, the individual reflection surfaces of the light modules can be calculated. The optical surfaces, be it the individual reflection surfaces or the light entry surface of the optical element or the imaginary, outer smooth surface, are calculated iteratively using numerical methods, for example, so that the light exit surface of the optical element can be illuminated evenly and brightly with parallel light from inside the optical element is.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 2016/0091653 A1 [0001]

Claims (12)

Motor vehicle lamp module (16) with a light-refracting optical element (18) which has a light entry surface (18.1), and with at least two light modules (20.1, 20.n), with each of which a light bundle (22.1, 22n) can be emitted, which is a part the light entry surface (18) is illuminated and a complementary part of the light entry surface (18.1) is not illuminated, characterized in that parts of the light entry surface (18.1) illuminated by two nearest adjacent light modules (20.1, ..., 20.n) are directly adjacent to one another without overlapping and that the at least two light modules (20.1, ..., 20.n) are set up to generate light bundles (22.1, ..., 22.n) whose light rays are directed onto an imaginary, outer smooth surface (30), which extends between the light modules (20.1, ..., 20.n) on one side and the light entry surface (18.1) on the other side, impinge perpendicularly. Motor vehicle light module according to Claim 1 , characterized in that the light entry surface (18.1) is a free-form surface. Motor vehicle light module according to Claim 1 , characterized in that the light entry surface (18.1) is a cylindrical surface whose guide curve (18.11) lies in a surface which is parallel to the main direction of incidence (x) of the light bundles (22.1, ..., 22.n) and whose generator ( y) is perpendicular to the main direction of incidence (x) of the light bundle and which is tangent-continuous. Motor vehicle light module (16) according to one of the preceding claims, characterized in that the optical element (18) is a light guide plate with equidistantly opposite broad sides, the light entry surface (18.1) and the light exit surface (18.2) each being a narrow side of the light guide plate. Motor vehicle light module (16) according to one of the preceding claims, characterized in that each light module (20.1, ..., 20.n) has a light source (24.1, ... 24.n) and a smooth reflective surface (27.1, ... , 27.n) which can be illuminated with light emanating from the light source. Motor vehicle light module (16) according to Claim 4 or 5 , characterized in that each light module (20.1, ..., 20.n) and the light entry surface (18) are matched to one another so that when the light sources (24.1, ... 24.n) are switched on, the light exit surface (18) gives a spatially constant luminance. Motor vehicle light module (16) according to Claim 6 , characterized in that the light exit surface (18.2) is provided with cushion optics or steps with which a signal light distribution can be generated. Motor vehicle light module (16) according to Claim 5 , characterized in that the light modules (20.1, ..., 20.n) have individual reflection surfaces (27.1, 27.n) which are designed and arranged so that they intersect. Motor vehicle light module (16) according to Claim 8 , characterized in that each of the individual reflection surfaces (27.1, ..., 27.n) has an optical axis and that each optical axis perpendicularly penetrates the outer, imaginary smooth surface (30). Motor vehicle light module (16) according to Claim 8 or 9 , characterized in that the light sources (24.1, ..., 24.n) of two light modules (20.1, ..., 20.n) next to each other lie symmetrically to a line in which the individual reflection surfaces (27.1, .. ., 27.n) of these two light modules (20.1, ..., 20.n). Motor vehicle light module (16) according to one of the Claims 8 until 10 , characterized in that the light modules (20.1, ..., 20.n) are designed so that when the light sources (24.1, ..., 24.n) are switched on, transverse to the line of intersection between two individual reflection surfaces (27.1 ,. .., 27.n) results in a steady course of the luminance. Motor vehicle light module (16) according to one of the Claims 4 until 11 , characterized in that the light sources (24.1, ..., 24.n) are individually controllable.

Images