EP2743565B1 - Light emitting device with finger-shaped light guide element and reflector comprising two facets - Google Patents

Description

The invention relates to a preferably provided for a motor vehicle light to fulfill a light function of the same lighting means with a finger-shaped light guide element according to the preamble of claim 1, as from EP 2 372 235 A2 A motor vehicle luminaire with a luminous means provided for fulfilling at least one of its one or more light functions according to the preamble of claim 15.

Depending on the configuration, each motor vehicle light fulfills one or more tasks or functions, for the fulfillment of which at least one light function of the motor vehicle light is provided. Light functions are, for example, in a configuration as a headlamp a function illuminating the road surface, or in a configuration as a signal light, a signal function, such as a Wiederblinklichtfunktion to the direction indicator or a brake light function to indicate a braking action, or. a limiting light function, such as a taillight function, to ensure visibility of the vehicle during the day and / or night, such as in a taillight or daytime running light configuration. Each light function must fulfill an example prescribed by law light distribution. The light distribution sets at least to be observed, colloquially known as brightness luminous flux in at least to be observed solid angle ranges.

Examples of motor vehicle lights are the Fahrzeugbug, on the vehicle flanks and / or on the side mirrors and arranged at the rear of vehicle rear lights, exit lights, for example, ambient lighting, marker lights, brake lights, fog lamps, reversing lights, and typically high set third brake lights, so-called Central, High-Mounted Braking lights, daytime running lights, headlamps and fog lights used as turning or cornering lights, as well as combinations thereof.

A motor vehicle luminaire essentially comprises a luminaire interior enclosed by a luminaire housing and a lens, and at least one at least one light source housed therein Illuminant for at least one light function of the motor vehicle light.

As light sources come in motor vehicle lights, inter alia, because of their low power consumption and low space requirements LEDs increasingly used. These consist of at least one light-emitting diode semiconductor chip, short LED chip, as well as at least one, for example, molded by injection molding, the at least one LED chip completely or partially enveloping primary optics. Also, automotive lights are known in which pure LED chips are used without molded primary optics. In the following, therefore, for the sake of simplicity, no distinction is made between light-emitting diode and LED chip and, instead, the term LED is used uniformly for both embodiments, unless explicitly stated otherwise. Outstanding properties of LEDs compared to other, conventional light sources of bulbs are a much longer life and a significantly higher light output with the same power consumption. As a result, and among other things also because of their more compact dimensions can be realized by using LEDs as a light source of light bulbs particularly compact automotive lights, which can be adapted to almost every imaginable installation situation.

At least one light source of the luminous means may be associated with one or more optical elements contributing to the shaping of, for example, a legally prescribed light distribution optical elements for directing light.

The lens is formed by a transparent cover which is usually made of a plastic material today, which closes off the interior of the lamp and protects the components housed therein, such as one or more lamps, reflectors and alternatively or additionally provided optical elements against the effects of weathering.

The luminaire housing or the interior of the luminaire can be subdivided into a plurality of chambers, each with its own light sources and / or illuminants and / or optical elements and, if appropriate, light disks, of which several chambers can be identical and / or each chamber can fulfill a different lighting function.

The mentioned optical elements may be at least one reflector and / or at least one lens and / or one or more in the beam path act between at least one light source of the illuminant and the lens disc arranged optical discs or the like.

For example, at least one reflector arranged behind at least one light source of at least one luminous means can be accommodated in the luminaire interior. The reflector may be formed at least in part by a separate component and / or by at least one part of the luminaire housing itself, for example by means of an at least partially reflective coating.

The lens itself may alternatively or additionally be formed as an optical element, for example by being preferably provided on the inside thereof with an optical structure contributing to the production of one or more of the aforementioned legally prescribed light distributions. This may possibly be dispensed with an optical disk.

Each optical element, even light sources, for example, the primary optic body of an LED or the glass bulb of a gas discharge or incandescent lamp, as well as form a flat lens and / or have optically effective surfaces, the beam path of the light from its formation at the site of light emission to affect the exit of the vehicle light. Optically effective surfaces on which an optical transition takes place between media with different optical refractive index are referred to herein as optical interfaces.

In this case, each optical element, each optical interface and any other optically active surface in the beam path of the light of a light function from the location of the light emission to the exit through the lens of the motor vehicle light so their part to comply with a desired and / or for example legally prescribed light distribution that on End, when the light has left the motor vehicle light after passing the lens, the corresponding light distribution of the corresponding light function is fulfilled, regardless of whether a more or less large part of the case expended light emerges differently from the predetermined light distribution from the motor vehicle light.

• der Genauigkeit der relativen Ausrichtung der zur Erzeugung der gewünschten Lichtverteilung benötigten, im Strahlengang von der mindestens einen Lichtquelle bis zum Austritt aus der Kraftfahrzeugleuchte durch die Lichtscheibe hindurch angeordneten Optikelemente. Die optische Güte ist beispielsweise um so geringer, je ungenauer die zur Erzielung der gewünschten Lichtverteilung benötigten Bauteile beginnend bei der Lichtquelle relativ zueinander ausgerichtet sind.
• der Präzision sämtlicher im Strahlengang vom Ort der Lichtemission bis zum Verlassen der Lichtscheibe optisch wirksamen Oberflächen, einschließlich optischer Grenzflächen, wie etwa der Oberflächenbeschaffenheit der erwähnten Optikelemente und/oder der Lichtquelle selbst. So trägt die Qualität beispielsweise der Oberflächen der Lichtaustritts- und der gegebenenfalls vorgesehenen Lichtumlenkflächen eines Lichtleiterelements wesentlich zur optischen Güte bei, weil das in ein Lichtleiterelement eingekoppelte Licht um so genauer einer vorgegebeben Lichtverteilung beitragend wieder aus dem Lichtleiterelement austritt, je präziser diese Oberflächen beschaffen sind.
• der Anzahl an optischen Übergängen bzw. optischen Grenzflächen im Strahlengang zwischen Medien mit unterschiedlichem optischem Brechungsindex.

An accompanying problem in the fulfillment of the requirements of, for example, legally prescribed light distribution of a light function of a Motor vehicle light by means of the known optical elements is only a limited optical quality. This is due to the fact that to fulfill a given light distribution, a more or less large part of the light used for a light function emerges from the motor vehicle light differently from the predefined light distribution. One reason for this is that the ratio of the light emerging in a desired light distribution from a motor vehicle light and associated with a light function to the optical quality emitted by the light source provided by the light function or light function is dependent, inter alia, on:

• the accuracy of the relative orientation of the required for generating the desired light distribution, in the beam path from the at least one light source to the exit of the motor vehicle light through the lens through optical elements arranged. The optical quality is, for example, the lower, the less accurate the components required to achieve the desired light distribution, starting at the light source, are aligned relative to one another.
• the precision of all optically effective in the beam path from the location of the light emission to the lens, including optical interfaces, such as the surface texture of the mentioned optical elements and / or the light source itself. So the quality contributes, for example, the surfaces of the Lichtaustritts- and optionally provided Lichtumlenkflächen a light guide element substantially to the optical quality, because the coupled into a light guide element light, the more precisely a given light distribution contributing again emerges from the light guide element, the more precisely these surfaces are arranged.
• the number of optical transitions or optical interfaces in the beam path between media with different optical refractive index.

Due to deviations from a theoretical, optimal arrangement and design of all optical elements and all optically active surfaces including optical interfaces so that a much higher luminous flux must be expended, as emerges from a motor vehicle light, for example, a legally prescribed light distribution accordingly. In this case, the optical quality deteriorates, the more light is divergent from a desired or required, for example legally prescribed light distribution is lost. This has one hand a high space requirement result, on the other hand, due to the required stronger and / or more light sources higher costs and also leads to an unnecessarily high power consumption associated with a higher load and thus design of the electrical system of a motor vehicle.

Instead of or in addition to one or more of the mentioned optical elements, optical fibers and / or light-conducting optical bodies increasingly used in motor vehicle lights for the purpose of light control, for example because they allow a hidden arrangement of the light source for a viewer.

With optical fiber elements, an improvement in the optical quality can be obtained in comparison to several individually or in groups mounted in the luminaire interior optical elements.

A light guide element consists of at least one Lichteinkoppelpartie and at least one Lichtauskoppelpartie. The light guide within the light guide element is virtually lossless by means of total internal reflection (TIR). Among other things, this can be at least partially dispensed with other optical elements. The material used to make optical fiber elements is predominantly transparent plastics. The production of the light guide elements can be done inexpensively and automatically by injection molding.

The Lichteinkoppelpartie comprises at least one for light coupling of at least one light source of at least one light emitting means provided Lichteinkoppelfläche.

The Lichtauskoppelpartie comprises at least one for light decoupling of the light coupled into the light guide element light, preferably arranged on the light guide front side, different from the Lichteinkoppelfläche light exit surface, and optionally at least one at least one light exit surface associated, different from the associated light exit surface, for example, on the light guide backside opposite the light exit surface arranged light deflection.

A light guide element, in the light of at least one light source at least a light incoupling surface on and at at least one of the light incoupling surface different light exit surface is coupled out again, it can be housed as a separate component, for example in the interior of a motor vehicle lamp or part of a light source.

By way of example, a luminous means may include one or more lightguide elements and one or more light sources emitting light from them, at least in part into the light sources that couple in at least one light guide.

As for the coupling of light in one or more light guide elements provided light sources LEDs are preferably provided. In the combination of light guide elements and LEDs, one light guide element per LED, a plurality of LEDs per light guide element or a plurality of light guide elements per LED can be used.

An optical waveguide element of such a luminous means can serve, for example, as a primary optic of one or more LEDs or be designed as such a primary optic, for example by the optical waveguide element being injection-molded directly onto one or more LEDs with its at least one light coupling surface.

At least the light incoupling surface, the light exit surface and the optionally provided Lichtumlenkfläche represent optically active surfaces of the light guide element. The light input surface and the light exit surface are optical interfaces as optically active surfaces. The remaining surfaces of the light guide element may also be optically active surfaces, provided that they contribute free from unwanted light extraction by total reflection for guiding light.

Also referred to as finger-shaped light guide elements light guide elements having a much elongated than flat expanded geometry, represent a special case, as apart from an optionally provided, in principle arbitrarily executable curvature, the light exit surface at least a portion of the light input surface in terms of the propagation of light in the light guide element opposite surface is. Thus, in the case of a straight or curved or oblique, cylindrical, fingertip-shaped optical waveguide element, the base and top surfaces of the cylinder comprise the light exit and light coupling surfaces which are opposite in the direction of propagation of the light in the optical waveguide element.

• sie weisen einen Mantel auf, der ein Volumen einschließt,
• sie weisen eine Zylinderachse auf, die aus den Mittelpunkten benachbart aufeinanderfolgender paralleler Querschnittsebenen gebildet ist,
• diese Zylinderachse kann gerade oder gekrümmt verlaufen,
• die Querschnittsgeometrien können entlang der Zylinderachse gleichmäßig oder veränderlich sein.

The term cylindrical is used to summarize certain shapes of geometric bodies:

• they have a coat that encloses a volume,
• they have a cylinder axis formed from the centers of adjacent successive parallel cross-sectional planes,
• this cylinder axis can be straight or curved,
• the cross-sectional geometries may be uniform or variable along the cylinder axis.

Examples of such geometric bodies are both straight or skewed general cylinders, cones, truncated cones, egg-shaped objects, ellipsoids and prisms in particular, as well as rotation bodies in general. In addition, rotational bodies are also included around curved curves. The term of the cylinder axis includes straight or curved curves that are formed by the centers of parallel cross-sectional planes through the geometric shape. Accordingly, in a curved optical waveguide element, the light accordingly propagates along the curved curve, wherein it is actually guided to this propagation by single or multiple total reflection on optically effective surfaces of the optical waveguide element.

Accordingly, the base and top surfaces need not be parallel to one another in the case of finger-shaped optical waveguide elements, for example if the finger-shaped optical waveguide element is curved or spirally running, for example.

In order for the light, coupled in an optical waveguide element, to emit sufficiently or contributing via the light exit surface, for example by law, the light exit surface and / or an optionally provided light redirecting surface can be provided with light outcoupling structures. Arranged at the light exit surface Lichtauskoppelstrukturen standing at an angle to the coupled into the light guide element light, in which no total reflection takes place and the light optionally refraction in the transition from the material of the light guide element to this surrounding medium in one or more, a predetermined light distribution sufficient or contributing directions emerges from the light exit surface.

Alternatively or additionally provided on a Lichtumlenkfläche Lichtauskoppelstrukturen, however, direct the light coupled into the light guide element at an angle to the light exit surface, in which there is no total reflection at this, so that the light the transition between the material of the light guide element and the surrounding medium in the area the light exit surface can happen. During this passage, the light in turn optionally exits from the light exit surface under refraction during the transition from the material of the light guide element to the medium surrounding it in one or more directions sufficient or contributing to a given light distribution.

These light extraction structures may include, for example, a plurality of prisms and / or pads and / or rollers as Lichtauskoppelemente.

In principle, one or more light exit surfaces and / or one or more optionally provided light deflection surfaces assigned to one or more light exit surfaces can be designed with light extraction structures and / or free of light extraction structures.

In finger-shaped light guide elements, in which the last optical interface is not immediately in front of the light source, on the one hand an efficient light guide through the finger-shaped light guide element and on the other hand, a sufficient large scattering on the light exit surface, for example, to sufficiently contribute to the fulfillment of a light function of a motor vehicle light a legal light distribution , And to obtain a homogeneous impression of the light exit surface in the illuminated state. This can be made possible by the most parallel possible coupling of light into the finger-shaped optical waveguide element via the light coupling surface, as well as light extraction structures consisting of an arrangement of light-scattering cushion, roller or prism elements on the light exit surface. Even a single, strongly curved light exit surface in the form of a so-called ball lens, depending on the size of the finger-shaped light guide element, only limited possible because light can no longer be scattered efficiently and far enough and / or gets into total reflection.

It is particularly aggravating that, in particular with finger-shaped light guide elements, a light exit surface provided with light coupling-out structures, the when used in motor vehicle lights in visible from outside the motor vehicle light through the lens through part of the lamp interior, as the quality impression is sustainably disturbing. In addition, light extraction structures are required in high quality in order to prevent the escape of light in a direction other than desired, can be produced only at great expense on the light exit surface of a finger-shaped light guide element. This is complicated by the visibility of arranged on the light exit surface Lichtauskoppelstrukturen, whereby not any, technically meaningful geometry for Lichtauskoppelstrukturen can be used, especially since this can cause an inhomogeneous impression in the illuminated state and thus in turn is quality-reducing.

To obtain a high optical quality is through DE 10 2006 034 070 A1 and through EP 1 881 258 A1 It is known to inject a light distribution body which generates a defined emission characteristic directly as primary optic to an LED, whereby on the one hand precise alignment of LED and light distribution body and, on the other hand, a reduction of the number of optical interfaces is obtained.

By JP 2-164612 A It is known to provide an arranged above a sun visor of a motor vehicle vanity mirror pivotally mounted above the vanity light guide element. The light guide element extends over the entire width of the make-up mirror. Light of a hidden in the sun visor light source is coupled both directly and indirectly via a reflector over the entire width of a light guide element engaging light input surface distributed in the light guide element. The reflector extends over the entire light input surface. The light source is placed in the center of the reflector. The reflector is V-shaped with flat legs. The light source is located directly opposite the light input surface. The optical waveguide element is arranged pivotable relative to the light source about an axis running parallel to the light coupling surface. The reflector is designed as a spring element, which spring-loaded the light guide element from a pivoted position, wherein the legs of the reflector are pressed into a common plane, back into a pivoted position. Due to the spring load, the light guide element pivots when opening a protective cap covering the make-up mirror.

By EP 1 801 492 A1 It is known to capture scattered light in a light coupling in a rod-shaped light guide element via a reflector, deflect and coupled via a second light function, further light input surface of the same light guide element in a different direction from the original light coupling direction. The light guide element fulfills different light functions in different directions.

By JP 6-203606 A It is known to arrange a reflector following a light guide element. The reflector is illuminated by means of an optical fiber element.

The invention is based on the object to develop a light source with a finger-shaped light guide element, which on the one hand meets high quality requirements and a high optical quality, and on the other hand, the fulfillment of a predetermined light distribution of a light function, for example, a motor vehicle light contributes and thus suitable for use preferably in a motor vehicle light is, and moreover, as simple and inexpensive to produce. It is another object of the invention to provide a motor vehicle light comprising at least one such illuminant.

The object is achieved in each case with the features of the independent claims.

A first subject of the invention accordingly relates to a luminous means comprising at least one finger-shaped, for example straight or preferably for example in a plane and / or particularly preferably three-dimensionally curved in space light guide element having a Lichteinkoppelfläche and one of the Lichteinkoppelfläche different light exit surface and one or more, the Lichteinkoppelfläche and the light exit surface interconnecting side walls, and at least one light source. The light emitted by the at least one light source enters the at least one finger-shaped light guide element exclusively via the light coupling surface.

At least one reflector is arranged in the beam path of the light between the at least one light source and the light coupling surface of the at least one finger-shaped light guide element.

The reflector deflects the light emitted by the at least one light source in its at least one light emission direction into at least one light input direction to the light input surface of the finger-shaped light conductor element.

In this case, the reflector consists of at least two reflector sections, a first main reflector section and at least one second secondary reflector section, which is preferably angled relative to the main reflector section.

The light exit surface of the finger-shaped light guide element is executed free of Lichtauskoppelstrukturen.

Preferably, the reflector consists of three reflector parts. A first, central main reflector section and on both sides of the main reflector section in each case one opposite the main reflector section preferably angled, second secondary reflector section.

If only two reflector sections are provided, these are a main reflector section and a secondary reflector section, for example, one side of the main reflector section or partially surrounding it and preferably angled relative to the main reflector section.

With more than three reflector sections, the secondary reflector sections may be arranged symmetrically or asymmetrically around the one main reflector section and / or be angled differently from the main reflector section and / or form further secondary secondary reflector sections partially separated from the main reflector section by at least one secondary reflector section therebetween. In this case, the one or more outer secondary reflector sections no longer bound themselves directly to the main reflector section, but instead are arranged separated from the main reflector section by one or more secondary reflector sections.

The central, for example, central reflector section collimates the light emitted by the light source and reflected in a Lichteinkoppelrichtung light such that it passes after its entry into the finger-shaped light guide element through the Lichteinkoppelfläche this free of interaction, for example, by total reflection with the optically effective surfaces forming side walls of the finger-shaped light guide element and below Refraction or free thereof at the transition from the optical fiber material to the surrounding medium through the light exit surface of the finger-shaped Light guide element exits again.

One or more adjacent sub-reflector portions direct the light in one or more Lichteinkoppelrichtungen to the light input surface, so that this one or more times interacts with the side walls under total reflection after being coupled into the finger-shaped light guide element by its light coupling surface and finally deflected at an angle to that of the main reflector and by the finger-shaped optical waveguide element propagated freely from interaction propagates light with refraction during the transition from the optical waveguide material to the surrounding medium and / or free from refraction from the light exit surface.

The one or more secondary reflector sections adjacent to the main reflector section may be designed such that they cover different light exit angle areas from the light exit area, the light exit angle areas overlap one another and / or smoothly, merge seamlessly into one another and / or adjoin one another and / or are separated from one another.

The light input surface of the finger-shaped light guide element may be flat, spherical or formed as a free-form surface.

The light incoupling surface designed with or without light-out coupling elements can therefore be curved flat or curved one or two-dimensionally or curved. In the case of the one-dimensional curved design, it is curved in one direction only, whereas in the case of a two-dimensional arched design, it is also arched in the remaining direction.

The light exit surface of the finger-shaped optical waveguide element may be flat or curved in one or two dimensions.

For example, the light exit surface, which is designed to be free of light output elements, can be curved in a straight direction or curved in one direction or curved / curved in both directions.

The side walls may be conical, cylindrical or rectangular.

The side walls may be provided with Lichtauskoppelstrukturen, which in the finger-shaped light guide element deflected light at an angle to the light exit surface, in which no total reflection occurs at this, so that the light can pass through the transition between the material of the finger-shaped light guide element and the surrounding medium in the region of the light exit surface. During this passage, the light in turn optionally exits from the light exit surface under refraction during the transition from the material of the light guide element to the medium surrounding it in one or more directions sufficient or contributing to a given light distribution.

The side walls may be grained, for example.

At least the one or more secondary reflector parts may be provided with a roll and / or cushion and / or prism structure.

One or more reflector sections, preferably one or more secondary reflector sections, can be structured, for example, with scattering elements.

The at least one light source that injects light into the finger-shaped light guide element is preferably an LED with the advantages described above.

It can be seen that the invention provides an arrangement of a reflector between one or more light sources and the light input surface of a finger-shaped light guide element realized.

The at least one light emission direction of the light source is directed transversely to the Lichteinkoppelrichtung via the light input surface of the light guide. The reflector deflects the light by reflection from the at least one light emission direction in Lichteinkoppelrichtung. At the same time, the reflector obtains a targeted shaping of the light bundle deflected in the light-incoupling direction, so that the light when discharging from the remote light exit surface of the finger-shaped light guide element contributes to the fulfillment of a light distribution of a light means to be filled by means of the illuminant comprising the finger-shaped light guide element. The reflector is divided into different parts. A central main reflector section collimates the light in such a way that, after it has entered the finger-shaped optical waveguide element, it is free of light by its light input surface Interaction, for example, by total reflection with the optically effective surfaces forming side walls of the finger-shaped light guide element happens and exits under refraction or free thereof through the light exit surface of the finger-shaped light guide element again. One or more adjacent sub-reflector portions direct the light in a direction to the light incoupling surface, that this one or more times interacts with the side walls under total reflection after coupling into the finger-shaped light guide element and finally exits at an angle from the light exit surface under refraction from the light guide material to the surrounding medium again ,

The invention accordingly provides a simplification of the geometry of the light exit surface of a finger-shaped light guide element of at least the finger-shaped light guide element and a light source comprising light source by using a reflector for light deflection and subsequent light coupling of the light emitted by a light source via the light input surface of the finger-shaped light guide element. The simplification of the geometry includes the omission of a structuring of the light exit surface previously required for obtaining a legally prescribed light distribution, for example by means of a cushion or roller structure.

At the same time, an improvement in the homogeneity of the appearance of the light exit surface in the on and off state of the light source is achieved, as well as the ratio of emitted from the light source, the expended luminous flux for exiting in a given light distribution from the light exit surface luminous flux corresponding higher optical efficiency. The latter, for example, with respect to the increasing demands on the energy efficiency of motor vehicles increasingly important because a reduction of useless, because, for example, outside the light distribution, emerging from the finger-shaped light guide element light a reduced power consumption to obtain the predetermined light distribution from the electrical system fuel or energy savings pulls.

By simplifying the geometry of the light exit surface of the finger-shaped light guide element, moreover, the production of the finger-shaped light guide element is simplified and thereby more cost-effective.

Advantages over the prior art arise in addition to a remedy The aforementioned disadvantages and a fulfillment of the problem by simplifying the production of the light-emitting surface of a finger-shaped light guide element, a reduction of this undesirable emerging light along with an improvement in the optical quality.

Further advantages are an improvement in the homogeneous impression of the appearance of the light exit surface in the on and off state.

Additional advantages result from obtaining a light distribution that can be adapted to a given light distribution, for example, to legal requirements such as various light functions. Unnecessary areas outside the given light distribution are not illuminated. Otherwise given away light can be used targeted and optimized.

In addition, as often required in automotive lighting, visually effective surfaces and / or optical interfaces that are visibly arranged outside of a motor vehicle light through the lens in the interior of the luminaire are designed to be free of light output structures that disturb the quality impression. In this way, a so-called "clean optics" can be realized with a light planing surface of the finger-shaped optical waveguide element that is as flat as possible, which is free of light coupling-out structures or general optical elements. In the prior art, on the other hand, light extraction structures in the form of cushioning and / or rolling and / or prisms and / or generally light-scattering and / or refractive elements are necessary in order to allow, for example, a light distribution of a light function of a motor vehicle light prescribed by law light distribution.

A second subject of the invention relates to a motor vehicle light with a lamp housing enclosed by a lamp housing and a lens, and at least one lamp accommodated in the lamp interior for fulfilling at least one light function of the motor vehicle lamp. In at least one housed in the interior of the lamp and to fulfill at least one light function of one or more light functions of the motor vehicle light provided bulbs is a previously described light source with a light source, a finger-shaped light guide element and arranged between the light source and the light input surface of the finger-shaped light guide element reflector. Of the Reflector deflects the light emitted by the light source in the light emission direction in the light input direction to the light input surface of the finger-shaped light guide element.

The motor vehicle light allows the use of the advantages of the above-described light source in the field of vehicle lighting.

The motor vehicle light may be formed, for example, as a tail lamp for a motor vehicle. Alternatively, the motor vehicle light can be configured as a high set third brake light.

Fig. 1

ein vorzugsweise für eine Kraftfahrzeugleuchte vorgesehenes Leuchtmittel mit einer Lichtquelle und einem fingerförmigen Lichtleiterelement, zwischen dessen Lichteinkoppelfläche und der Lichtquelle ein Reflektor angeordnet ist, der das von der Lichtquelle in deren Lichtabstrahlrichtung abgestrahlte Licht in Lichteinkoppelrichtung zur Lichteinkoppelfläche umlenkt, in einer Draufsicht.

Fig. 2

das Leuchtmittel aus Fig. 1 in einer Seitenansicht.

Fig. 3

das Leuchtmittel aus Fig. 1 in einer perspektivischen Ansicht.

Fig. 4

das Leuchtmittel aus Fig. 1 in einer Vorderansicht auf die Lichtaustrittsfläche des fingerförmigen Lichtleiterelements gesehen.

The invention will be explained in more detail with reference to embodiments shown in the drawings. Therein, like reference characters designate like or equivalent elements. For clarity, only reference numerals in the individual drawings are shown, which are required for the description of the respective drawing. The proportions of the individual elements to one another do not always correspond to the actual size ratios, since some shapes are simplified and other shapes are shown enlarged in relation to other elements for better illustration. In a schematic representation:

Fig. 1

a preferably provided for a motor vehicle light bulb having a light source and a finger-shaped light guide element, between the light input surface and the light source, a reflector is arranged, which deflects the radiated from the light source in the Lichtabstrahlrichtung light in Lichteinkoppelrichtung to the light input surface, in a plan view.

Fig. 2

the bulb off Fig. 1 in a side view.

Fig. 3

the bulb off Fig. 1 in a perspective view.

Fig. 4

the bulb off Fig. 1 seen in a front view of the light exit surface of the finger-shaped light guide element.

One in the Fig. 1 to Fig. 4 Wholly or partially illustrated, preferably provided for a motor vehicle light bulbs 01 comprises at least one preferably as an LED light source 02, at least one, for example, straight or in a plane and / or curved in space three-dimensionally extending finger-shaped light guide element 03 and at least one arranged in the beam path of the light between the light source 02 and the finger-shaped light guide element 03 reflector 07th

One or more light sources 02 may be associated with a finger-shaped light guide element 03 or a plurality of finger-shaped light guide elements 03 of one or more light sources 02, even if only one light source 02 and / or only one finger-shaped light guide element 03 is discussed later. The same applies to the reflector (s) 07. Along with a plurality of finger-shaped light guide elements 03, the light source 01 can also have a plurality of reflectors 07, each of which reflects light to a finger-shaped light guide element 03. If the light source 01 has a plurality of finger-shaped optical waveguide elements 03, then it also requires a plurality of reflectors 07, one per finger-shaped optical waveguide element 03. If there are several light sources 02 per finger-shaped optical waveguide element 03, a reflector 07 per finger-shaped optical waveguide element 03 can, but is not necessarily, sufficient.

The finger-shaped optical waveguide element 03 has a light input surface 04 associated with at least one light source 02 and a light exit surface 05 different from the light coupling surface 04. The finger-shaped light guide element 03 furthermore has one or more side walls 06 which connect the light input surface 04 and the light exit surface 05 to one another.

The light emitted by the light source 02 in its at least one light emission direction LA enters the finger-shaped light guide element 03 exclusively via the light coupling surface 04.

The reflector 07 is arranged in the beam path of the light between the light source 02 and the light input surface 04 of the finger-shaped light guide element 03. The reflector 07 redirects the light emitted by the at least one light source 02 in its at least one light emission direction LA into at least one light input direction LE to the light coupling surface 04 of the finger-shaped light conductor element 03.

The reflector 07 consists of at least two reflector parts 08, 09. In the Reflector sections 08, 09 are a main reflector section 08 forming a first reflector section and at least one secondary reflector section 09 forming a second reflector section, preferably angled relative to the main reflector section 08.

The main reflector section 08 reflects and collimates the light emitted by the light source 02 in one or more light emission directions LA during the deflection in at least one Lichteinkoppelrichtung LE such that it after its entry into the finger-shaped light guide element 03 by the Lichteinkoppelfläche 04 this free of interaction, for example by Total reflection with the optically effective surfaces forming side walls 06 of the finger-shaped light guide element 03 as through the beam path LH in Fig. 1 shown passes and with refraction at the transition from the light guide material to the surrounding medium or free thereof exits through the light exit surface 05 from the finger-shaped light guide element 03 again.

The at least one secondary reflector section 09 adjacent to the main reflector section 08 reflects and deflects the light emitted by the light source 02 in one or more light emission directions LA during the deflection in at least one light input direction LE to the light input surface 04 such that this enters the finger-shaped light guide element 03 after it has entered its light coupling surface 04 one or more times with the side walls 06 of the finger-shaped optical waveguide element 03 as through the beam path LN in Fig. 1 shown under total reflection interacts and finally at an angle relative to the deflected by the main reflector 09 and represented by the finger-shaped light guide element 03 as shown by the beam LH free of interaction with the side walls 06 propagated light under refraction at the transition from the optical fiber to the surrounding medium and / or freely exits from the light exit surface 05 again.

This angle can contribute to the fulfillment of a given light distribution. The angle can be an angular range.

In this case, different angles and / or angle ranges of different secondary reflector parts 09 can be obtained.

It is to be shown in Fig. 1 to hold that in the light incidence direction LE supposedly from the light source 02 to the light incidence surface 04 extending light only seems to come directly from the light source 02, but in fact has already been reflected by the reflector 07. The in plan view in Fig. 1 In Lichteinkoppelrichtung LE extending light leaves the main reflector section 08 of the reflector 07 thereby from below the light source 02, which makes it to the supposedly wrong representation in Fig. 1 comes. Fig. 2 shows in the side view of the page, on which the supposedly wrong representation is based.

The light exit surface 05 of the finger-shaped light guide element 03 is designed to be free of light extraction structures.

At least one secondary reflector section 09 can be angled relative to the main reflector section 08. Preferably, all secondary reflector sections 09 are angled relative to the main reflector section 08.

The light input surface 04 of the finger-shaped light guide element 03 may be flat, spherical or formed as a free-form surface.

For example, the light coupling-in surface 04, which is designed with or without light-outcoupling elements, can be curved flat or curved in one or two dimensions or curved. In the one-dimensionally curved embodiment, the light incoupling surface 04 is curved in only one direction, corresponding to only one curvature about a first axis, whereas the light incoupling surface 04 is arched in a two-dimensional curved embodiment in the remaining direction, corresponding to a further curvature by a second, for example skewed to the first axis or this intersecting axis.

Alternatively or additionally, the light exit surface 05 of the finger-shaped optical waveguide element 03 may be flat or curved in one or two dimensions. In the one-dimensional curved embodiment, the light exit surface 05 is curved in only one direction, corresponding to only one curvature about a first axis, whereas the light exit surface 05 is arched in a two-dimensional curved embodiment in the remaining direction, corresponding to a further curvature to a second, for example skewed to the first axis or this intersecting axis.

The side walls 06 of the finger-shaped light guide element 03 may be conical, cylindrical or rectangular.

The side walls 06 of the finger-shaped light guide element 03 may be provided with Lichtauskoppelstrukturen which direct into the finger-shaped light guide element 03 coupled light at an angle to the light exit surface 05, in which no total reflection occurs at this, so that the light the transition between the material of the finger-shaped light guide element 03 and the surrounding medium in the region of the light exit surface 05 can happen. In this passage, the light in turn optionally exits from the light exit surface 05, with refraction when passing from the material of the finger-shaped light guide element 03 to the surrounding medium in one or more directions, for example a predetermined light distribution.

Alternatively or additionally, the side walls 06 may be grained.

At least one secondary reflector section 09 can be provided with a roll and / or cushion and / or prism structure 10 in order to deflect the light in one or more desired Lichteinkoppelrichtungen LE.

At least one reflector section 08, 09, preferably one or more secondary reflector sections 09, can be structured with scattering elements, for example in the form of the aforementioned roll and / or cushion and / or prism structure 10. These may be provided to contribute to one or more particular Lichteinkoppelrichtungen LE.

• sie unterschiedliche Lichtaustrittswinkelbereiche aus der Lichtaustrittsfläche 04 des fingerförmigen Lichtleiterelements 03 abdecken,
• die von ihnen abgedeckten Lichtaustrittswinkelbereiche aus der Lichtaustrittsfläche 04 des fingerförmigen Lichtleiterelements 03 einander überlappen und/oder
• die von ihnen abgedeckten Lichtaustrittswinkelbereiche aus der Lichtaustrittsfläche 04 des fingerförmigen Lichtleiterelements 03 gleichmäßig, nahtlos ineinander übergehen, und/oder
• die von ihnen abgedeckten Lichtaustrittswinkelbereiche aus der Lichtaustrittsfläche 04 des fingerförmigen Lichtleiterelements 03 aneinander angrenzen und/oder
• die von ihnen abgedeckten Lichtaustrittswinkelbereiche aus der Lichtaustrittsfläche 04 des fingerförmigen Lichtleiterelements 03 voneinander getrennt sind.

The one or more secondary reflector sections 09 adjacent to the main reflector section 08 can be designed such that:

• they cover different light exit angle ranges from the light exit surface 04 of the finger-shaped light guide element 03,
• the light exit angle ranges covered by them from the light exit surface 04 of the finger-shaped light guide element 03 overlap one another and / or one another
• the light exit angle ranges covered by them from the light exit surface 04 of the finger-shaped light guide element 03 smoothly, seamlessly merge into one another, and / or
• the light exit angle ranges covered by them from the light exit surface 04 of the finger-shaped light guide element 03 adjoin one another and / or
• the light exit angle ranges covered by them are separated from one another by the light exit surface 04 of the finger-shaped light guide element 03.

In this way, an individual adaptation of a given light distribution can be made contributing.

It is important to emphasize that the reflector 07 of the lamp 01 may comprise only two reflector sections 08, 09, a main reflector section 08 and a secondary reflector section 09 preferably angled relative to the main reflector section 08. The secondary reflector section 09 is arranged on one side of the main reflector section 08 or partially surrounding it.

Alternatively, the reflector 07 of the luminous means 01 can consist of three reflector sections, a first, central main reflector section 08 and, on both sides of the main reflector section 08, a second secondary reflector section 09 preferably angled relative to the main reflector section 08.

• entsprechend symmetrisch oder asymmetrisch um die eine Hauptreflektorpartie (08) herum angeordnet sein, und/oder
• unterschiedlich gegenüber der Hauptreflektorpartie 08 angewinkelt sein, und/oder
• teils weitere, außenliegende Nebenreflektorpartien 09 bilden, die gar nicht mehr selbst unmittelbar an die Hauptreflektorpartie 08 angrenzen, sondern vielmehr durch eine oder mehrere dazwischenliegende Nebenreflektorpartien 09 getrennt von der Hauptreflektorpartie 08 angeordnet sind.

Alternatively, the reflector 07 of the light source 01 may consist of more than three reflector sections 08, 09. In this case, a main reflector section 08 and three or more secondary reflector sections 09 are provided. The secondary reflector parts 09 can:

• be arranged symmetrically or asymmetrically around the one main reflector section (08), and / or
• be angled relative to the main reflector section 08, and / or
• form partly further, outer secondary reflector sections 09, which no longer directly adjoin itself to the main reflector section 08, but rather by one or more intermediate sub-reflector sections 09 are arranged separately from the main reflector section 08.

The illuminant 01 can be provided for use in a motor vehicle luminaire with a luminaire interior enclosed by a luminaire housing and a lens, in the luminaire interior of which at least one illuminant 01 fulfills at least one light function of the motor vehicle luminaire is housed.

It is equally important to emphasize that the light coupling takes place in the finger-shaped light guide element 03 by the finger-shaped light guide element 03 is attached to a reflector 07 denoted as indirectly. The reflector 07 in turn may be directly connected to a light source 02, for example an LED. The reflector 07 is specially adapted to the geometry of the finger-shaped light guide element 03 and converges the light accordingly, before it enters the finger-shaped light guide element 03 via the light coupling surface 04. The light exit surface 05 of the finger-shaped optical waveguide element 03 is little or not curved and executed free of optical elements. Nevertheless, for example, a legally prescribed light distribution is made possible. Light from the light exit surface 05 of the finger-shaped light guide element 03 is thereby also of angular ranges greater than 45 ° to the in Fig. 1 still visible with the optical axis coincident with the optical path LH.

In the Fig. 1 to Fig. 4 are the light input surface 04 planar, the side walls 06 conical and the light exit surface 05 easily curved two-dimensionally executed. The reflector 07 covers the light incoupling surface 04 of the finger-shaped light guide element 03 in whole or in part. The reflector 07 consists of a centered main reflector section 08 and these surrounding angled parabolic or freiform secondary reflector sections 09. The main reflector section 08 and the preferably angled secondary reflector sections 09 can in turn be made with optical structures, for example with cushions, preferably with a roll and / or cushion and / or Prism structure 10 be damaged.

Light coming from the central main reflector section 08, enters via the light coupling surface 04 in the finger-shaped light guide element 03 and passes this according to the beam path LH at least for the most part without interacting with the side walls 06. At the light exit surface 05 only little or no refraction of light takes place. The latter is dependent on the curvature of the light exit surface 05.

Light from the preferably angled secondary reflector sections 09 enters the finger-shaped optical waveguide element 03 via the light coupling surface 04 and passes this in accordance with the beam path LN with one or more interactions with the side walls 06 of the finger-shaped optical waveguide element 03. The angle of incidence of the light is selected such that Total reflection takes place and the light in a to optical axis steeper angle on the light exit surface 05 occurs, as is the case with the beam path LH. At the light exit surface 05 occurs, depending on the curvature, another refraction of light instead. This light thus operates the outer or inner angular ranges of a given or desired light distribution.

By a combination of the preferably angled secondary reflector parts 09, the curvature of the light exit surface 05 and optionally the scattering means arranged on the reflector 07 roll and / or cushion and / or prism structures 10 and / or scattering elements can be a uniform, seamless course of the finger-shaped light guide element 03 corresponding to the beam path LH directly passing light and the finger-shaped light guide element 03 corresponding to the beam path LN on the side walls 06 by total reflection or multiple deflected light can be achieved. The finger-shaped light guide element 03 thereby scatters the light into wide angular ranges of more than 45 ° with simultaneously only slightly curved light exit surface 05 and without visible optical elements on the light exit surface 05.

The risk of uncontrolled decoupling, so-called leakage light along with a deterioration of the optical quality is thereby significantly reduced.

The light input surface 04 of the finger-shaped light guide element 03 may be planar, spherical or designed as a free-form surface. The side walls 06 may be conical, cylindrical or rectangular. The light exit surface 05 of the finger-shaped light guide element 03 can be designed as described above. In addition, in order to obtain an even stronger light mixture, the side walls 06 of the finger-shaped light guide element 03 may be grained.

The reflector 07 can also be designed as a direct reflector 07 or as a free-form surface. The surface of the reflector 07 may be grained or provided with scattering elements, for example with a roll and / or cushion and / or prism structure 10.

By using a point light source 02, as it is realized by an LED, the optical quality achievable with the invention can be further increased, because such a light source an optimal design of the entire Beam path of the light generation until it leaves the light source 01 through the light exit surface 05 of the finger-shaped light guide element 03 allows. In this way, the unwanted leakage of light at other than the intended locations of the finger-shaped optical waveguide element 03, the so-called leakage light, at least approximately completely avoided, regardless of which type LED is used as the light source 02.

In this case, different types of LEDs differ essentially by their electrical contacting and the presence of an encapsulation and / or primary optics, as will become apparent from the following explanations.

An LED comprises in addition to the already mentioned at least one LED chip and at least one contact means for electrically contacting the LED chip. Typically, each LED has a bonding wire per LED chip, which each electrically contacts a LED chip. This bonding wire forms a first contact means for the LED chip of the LED. The bonding wire may be connected to a first electrical connection, which may be provided for electrical contacting of the LED, for example with a first conductor track of a luminous means carrier. A second contact means for the LED chip of the LED forms the LED chip itself. For electrical contacting of the LED chip may be connected to a second electrical connection, which may be provided for electrical contacting of the LED, for example with a second conductor of a lamp carrier.

In addition, the LED can have a primary reflector directly surrounding the LED chip. This primary reflector can be formed, for example, by walls of a recess surrounding the LED chip and / or by a cup in which the LED chip is arranged. The cup may be connected to, form or include the mentioned second port or be encompassed by it.

In special versions of LEDs, individual or all of the contact means themselves can form the electrical connections, as explained below for the different contacting possibilities of LEDs.

LEDs are known for through-hole mounting (THT), Surface Mounted Device (SMD) LEDs and LEDs where the bare-chip LED chip (Chip On Board) is bonded directly to the illuminant carrier.

THT LEDs are the commonly known type LEDs. They are also referred to as leaded LEDs, since they are made of a transparent at least in a desired emission direction encapsulation, e.g. in the form of an encapsulation or an encapsulation, which includes a LED chip with a first electrical connection, for example in the form of an anode terminal connecting bonding wire and connected to a second electrical connection, for example in the form of a cathode terminal, LED chip. From the encapsulation protrude only the designated as little legs wires of the first electrical connection and the second electrical connection as the anode and cathode terminals of the THT-LED. The second electrical connection embodied, for example, as a cathode connection can in this case be provided with a cup mentioned above, in which the LED chip is arranged. The bonding wire leads from the example executed as an anode terminal first connection from outside the cup coming to the LED chip.

SMD LEDs consist of a leadframe with at least one mounting surface for at least one LED chip and electrical connection surfaces. The leadframe is partially encapsulated by a plastic body with at least one recess freeing at least one mounting surface. The electrical connection surfaces of the leadframe are also kept free as the electrical connections of the SMD LED for later surface mounting. The at least one LED chip is arranged and electrically contacted at the bottom of the at least one recess extending to the at least one mounting surface. In this case, the LED chip is arranged on a first portion of the leadframe connected to at least one first electrical connection area. A bonding wire connects the LED chip to a second portion of the leadframe, which in turn is connected to at least one second electrical pad. The reaching at its base to the mounting surface recess may be designed reflector-like. The walls of the recess form the above-mentioned primary reflector. Here, the walls can be coated reflective.

COB LEDs consist of one directly on a light source carrier to be arranged, unhoused LED chip and a bonding wire. The back side of the LED chip forms the first electrical connection of the COB LED. For electrical contacting of the LED chip is electrically connected on its back directly to a first conductor of a light source carrier, for example by soldering or welding. The bonding wire forming the second electrical connection of the COB LED is also electrically connected to a second conductor track of the illuminant carrier, for example by soldering or welding.

For the sake of completeness, it should additionally be mentioned that other contacts, such as the so-called flip-chip structure are possible, in which the contact means of the LED chip are connected directly to a contacted substrate. In these cases, no bonding wire is used.

One or more of the aforementioned light source carriers may be part of a light source 01.

The invention is particularly applicable in the field of the production of light sources, as may be provided, for example, for motor vehicle lights, as well as in the field of production of motor vehicle lights industrially applicable.

LIST OF REFERENCE NUMBERS

01

Lamp

02

light source

03

Finger-shaped light guide element

04

light injection

05

Light-emitting surface

06

Side wall

07

reflector

08

Main reflector section

09

Subreflector game

10

Roll and / or cushion and / or prism structure

LA

light emission

LE

Lichteinkoppelrichtung

LH

Beam path of the collimated by the main reflector section light through the finger-shaped light guide element

LN

Beam path of the deflected by a secondary reflector section light through the finger-shaped light guide element

Claims (15)

1. A lighting means (01) comprising at least one light source (02) and at least one finger-shaped light guide element (03) with a light in-coupling surface (04) and with a light emitting surface (05), which is distinct from the light in-coupling surface (04), and one or a plurality of side walls (06) connecting the light in-coupling surface (04) and the light emitting surface (05) to each other, wherein the light being emitted by the at least one light source (02) in its at least one light emission direction (LA) enters exclusively via the light in-coupling surface (04) into the light guide element (03), the light emitting surface (05) of the light guide element (03) is designed free from light out-coupling structures,
   characterised in that:

   - at least one reflector (07) is arranged in the optical path of the light between the at least one light source (02) and the light in-coupling surface (04) of the at least one light guide element (03),

   - the reflector (07) deflects in at least one light in-coupling direction (LE) the light being emitted by the at least one light source (02) in its at least one light emission direction (LA) to the light in-coupling surface (04) of the light guide element (03),

   - the reflector (07) consists of at least two reflector portions (08, 09), one main reflector portion (08) and at least one sub-reflector portion (09),

   - the main reflector portion (08) collimates the light while it is being deflected such that, after the light enters through the light in-coupling surface (04) into the light guide element (03), it passes through it free from interaction with the side walls (06) and is emitted through the light emitting surface (05), and in that

   - the at least one sub-reflector portion (09) directs the light while it is being deflected such that, after the light enters through the light in-coupling surface (04) into the light guide element (03), it interacts under total reflection once or multiple times with the side wall or side walls (06) and is emitted from the light emitting surface (05) at an angle in relation to the light being deflected by the main reflector (09) and being propagated free from interaction through the light guide element (03).
2. The lighting means as recited in claim 1,
   characterised in that
   the light in-coupling surface (04) of the light guide element (03) is formed to be flat, spherical or as a free-form surface.
3. The lighting means as recited in claim 1 or 2,
   characterised in that
   the light in-coupling surface (04) is formed to be flat or one- or two-dimensionally vaulted.
4. The lighting means as recited in claim 1, 2 or 3,
   characterised in that
   the light emitting surface (05) is formed to be flat or one- or two-dimensionally vaulted.
5. The lighting means as recited in one of the previous claims,
   characterised in that
   the side walls (06) are designed to be conical, cylindrical or rectangular.
6. The lighting means as recited in one of the previous claims,
   characterised in that
   the one or more side walls (06) are provided with light out-coupling structures, which direct the light coupled into the light guide element (03) toward the light emitting surface (05) at an angle at which no total reflection takes place at the light emitting surface (05) so that the light can pass the transition between the material of the light guide element (03) and the medium surrounding it in the area of the light emitting surface (05).
7. The lighting means as recited in one of the previous claims,
   characterised in that
   the side walls (06) are grained.
8. The lighting means as recited in one of the preceding claims,
   characterised in that
   at least one sub-reflector portion (09) is angled in relation to the main reflector portion (08).
9. The lighting means as recited in one of the previous claims,
   characterised in that
   at least one sub-reflector portion (09) is provided with a barrel structure and/or a cushion structure and/or a prism structure (10).
10. The lighting means as recited in one of the previous claims,
    characterised in that
    at least one reflector portion (08, 09) is structured by scattering elements (10).
11. The lighting means as recited in one of the previous claims,
    characterised in that
    the one or more sub-reflector portions (09) adjacent to the main reflector portion (08) are designed such that:

    - they cover different light emitting angle ranges from the light emitting surface (04),

    - the light emitting angle ranges overlap each other, and/or

    - the light emitting angle ranges evenly, seamlessly merge into one another, and/or

    - the light emitting angle ranges are adjacent to each other, and/or

    - the light emitting angle ranges are separate from one another.
12. The lighting means as recited in one of the previous claims,
    characterised by
    two reflector portions (08, 09), one main reflector portion (08) and one sub-reflector portion (09), wherein the sub-reflector portion (09) is arranged on one side of the main reflector portion (08) or such as to partially surround the main reflector portion (08).
13. The lighting means as recited in one of the claims 1 to 11,
    characterised in that
    the reflector consists of three reflector portions, one centrally arranged main reflector portion (08) and one sub-reflector portion (09) arranged on each of both sides of the main reflector portion (08).
14. The lighting means as recited in one of the claims 1 to 11,
    characterised by
    more than three reflector portions (08, 09), wherein the sub-reflector portions (09):

    - are arranged symmetrically or asymmetrically around the one main reflector portion (08), and/or

    - are angled differently in relation to the main reflector portion (08), and/or

    - partly form further, externally located sub-reflector portions (09).
15. A motor vehicle lamp with a lamp interior enclosed by a light lens and a lamp housing and with at least one lighting means (01) for fulfilling at least one light function of the motor vehicle lamp, the lighting means (01) being accommodated in the lamp interior,
    characterised by
    at least one lighting means (01) as recited in one of the previous claims for fulfilling at least one light function or a plurality of light functions of the motor vehicle lamp.

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