CN217082287U

CN217082287U - Lighting element and vehicle interior part

Info

Publication number: CN217082287U
Application number: CN202122880714.4U
Authority: CN
Inventors: 马克西姆·米西
Original assignee: Faurecia Innenraum Systeme GmbH
Current assignee: Faurecia Innenraum Systeme GmbH
Priority date: 2020-11-23
Filing date: 2021-11-23
Publication date: 2022-07-29
Anticipated expiration: 2031-11-23
Also published as: DE102020214698A1

Abstract

The utility model relates to a lighting element (1) for vehicle passenger cabin, it has: at least one optical fiber (2) extending in a longitudinal direction and arranged to emit light in a transverse direction extending perpendicular to the longitudinal direction; and at least one reflective fibre (3) arranged parallel to the optical fibre (2) and arranged to reflect light emitted by the optical fibre 2. The lighting element (1) further comprises a light-transmitting cover layer (4) which surrounds the optical fibers (2) and the reflective fibers (3), wherein the cover layer (4) has a first section (6) which is curved about a bending axis (5) extending in the longitudinal direction.

Description

Lighting element and vehicle interior part

Technical Field

The subject of this document is a lighting element, in particular suitable for a vehicle passenger compartment, and a vehicle interior trim part comprising a lighting element. Furthermore, a semi-finished product for producing the lighting element can be provided.

Background

Lighting elements with optical fibres are well known in the art. In particular, in modern vehicle cabins, for example, laterally radiating optical fibers are used in order to provide indirect illumination of the cabin via interior trim parts, such as a sub-dashboard, door panels or instrument panels.

For example, DE 102018203856 a1 relates to a lighting complex having a woven material which provides planar lighting using a plurality of laterally radiating optical fibers arranged parallel to one another. In order to protect the optical fibers, compressible, parallel wire bundles for absorbing loads and, for example, a covering transparent plastic layer are proposed.

It has however been shown that the light-emitting capability of the above-mentioned known illumination complexes is affected in the case of a smaller illumination area, since the number of optical fibers is reduced by space limitations. In particular on-line coarse

In the case of line lighting of several millimeters, the luminous capacity is severely affected.

SUMMERY OF THE UTILITY MODEL

The object of the present disclosure is therefore: an easily manufacturable lighting element is developed which has an improved luminous capacity in the case of small or narrow lighting areas.

The object is achieved by a lighting element according to the invention and by a vehicle interior trim part comprising said lighting element. Particular embodiments are described in the specification and by the drawings.

The lighting element proposed here for a vehicle passenger compartment comprises: at least one optical fiber extending in a longitudinal direction and arranged to emit light in a transverse direction perpendicular to the longitudinal direction; and at least one reflective fiber arranged parallel to the optical fibers and arranged to reflect light emitted by the optical fibers. Typically only a portion of the light emitted by the optical fiber is reflected by the reflective fiber. This is for example because only a part of the emitted light is emitted in the spatial direction corresponding to the reflective fiber and transmission into the reflective fiber always occurs in addition to reflection on the reflective fiber. The lighting element also has a light-transmitting cover layer which surrounds the optical fibers and the reflective fibers. The cover layer includes a segment that is curved about a bending axis extending in a longitudinal direction.

Generally, an optical fiber includes a core layer and a protective layer and is constructed such that the outer periphery of the core layer is covered with the protective layer. Due to the material selected for the core layer or the protective layer, the refractive index and the reflectivity can be selected accordingly such that light guidance in the core layer is possible by total reflection at the protective layer. According to the utility model discloses the regulation: the optical fibers are configured as side-emitting optical fibers for emitting light from the sides in a suitable manner. This can be achieved, for example, by mixing scattering particles into the core layer and/or by locally removing or roughening the protective layer. Local removal or roughening has the advantage that a light pattern can be generated. Compared with the prior art, the illumination element proposed here is superior in that: the cover layer has a curved section and surrounds the optical fibers and the reflective fibers. Light emitted laterally by the optical fibers is typically emitted through a light-transmissive cover layer. The solid angle of the light emitted laterally by the optical fiber, which is available for illuminating the cover layer, can be enlarged by the curved cover layer with respect to the solid angle of the illumination device known from the prior art. More light emitted by the optical fibres can thus be provided for illuminating the other side of the cover layer, in this way improving the emission capability of the lighting element. Furthermore, a smaller number of optical fibers can be sufficient to achieve the desired emission capability of the lighting element. Furthermore, the illumination element proposed here can be of small thickness and preferably also allows a design with a narrow emission area, in particular a linear emission area of small thickness, while avoiding influences on the luminous efficacy of the illumination element or maintaining the luminous efficacy of the illumination element as good as possible. Alternatively, such saved space may be used for adding further optical fibers, so that the light coupling efficiency of light from one light source to the lighting element may be improved in accordance with the enlarged etendue.

The optical fibers are often arranged closer to the curved section of the cover layer and/or the bend of the cover layer formed by the curved section than the reflective fibers. Furthermore, the spacing of the optical fibers to the bending axis may be less than the spacing of the reflective fibers to the bending axis. In particular, the arrangement of the reflective fibers at a distance from the bending axis that is greater than the distance of the optical fibers from the bending axis makes it possible to: the reflective fibers reflect light laterally emitted by the optical fibers in a particularly beneficial direction towards the cover layer. The emitted light may be reflected, for example, directionally, diffusely, or a combination of both, by the reflective fibers. In particular, the reflective fibers may have a smooth surface for directing the emitted light back by directional reflection or a rough surface for diffusely reflecting the emitted light. The portion of the light returned by the reflective fibers, in particular the light then returned through the cover layer, makes an additional contribution to the luminous power of the lighting element and enables a more uniform light distribution. This relates in particular to the light emitted by the optical fibres, which radiate this light in a direction away from the cover layer.

Preferably, the cover layer has a first side and a second side, the first side being arranged for illumination or for emitting light emitted by the optical fibers, and the second side being arranged for absorbing light emitted by the optical fibers. The first side may constitute a front side of the cover layer and the second side may constitute a back side of the cover layer. The optical fibers and/or the reflective fibers may be arranged on the second side, in particular on the back side of the cover layer. The bending axis may be arranged on the second side, in particular on the back side of the cover layer. By arranging the bending axis on the rear side, the cover layer is bent towards its rear side, so that an enlarged front side area is obtained which is accessible from the front, in particular visible from the front. In other words, the solid angle of emission of the light of the optical fiber for illuminating the front side of the lighting element is enlarged, thereby improving the luminous capacity of the lighting element. Furthermore, in the case of fibers arranged on the back side and bending axes arranged on the back side, the cover layer can provide protection against external influences, in particular mechanical influences.

Furthermore, provision can be made for: the cover layer is bent such that the bending angle of the bent section of the cover layer about the bending axis is at least 45 degrees, preferably at least 135 degrees, particularly preferably 180 degrees. As the bending angle increases, the total thickness of the illumination element can be reduced and the solid angle for illumination of the light emitted by the optical fiber can be enlarged at least in the range from zero to 180 degrees, whereby the light emitting capability of the illumination element can be improved. The bending angle is substantially equal to the maximum angle between two orthogonal lines (orthologies) of the bent section of the cover layer.

It can be provided that: the cover layer has two further sections extending on both sides of the bending axis and is folded over in such a way that the fibers arranged in one of the further sections rest on the other of the further sections and/or on the fibers arranged in the other of the further sections. The total thickness of the lighting element can be derived, for example, from the sum of one diameter of the reflective fibers or optical fibers, two thicknesses of the cover layer and, if provided, one thickness of the adhesive layer, as the case may be. A compact construction with a small overall thickness of the lighting element can thus be achieved. If the opposite fibres are offset from each other, the total thickness of the lighting element will be small, or if more than one layer of fibres is provided on one of the further sections, the thickness will be large.

The lighting element may comprise an adhesive layer. The bonding layer may be arranged to bond the optical fibres, the reflective fibres and/or the cover layer to each other. The adhesive layer may, for example, be arranged between two further segments of the cover layer, in particular between the fibers of the respective segments of the two further segments. The adhesive layer prevents the folded-over covering layer from moving back or flipping back and at the same time improves the stability of the lighting element. Alternatively or additionally, a seam can be provided which holds the two further sections together.

In particular, the cover layer can be folded such that the two further sections are arranged parallel to one another. In this case, a particularly small thickness of the lighting element can be achieved.

In some embodiments, the reflective fibers may have a reflectivity of at least 0.1, preferably at least 0.3, particularly preferably at least 0.7. In particular, the reflective fibers can be textile fibers, in particular synthetic fibers made of polyester, polypropylene or polyamide. Preferably, the reflective fibers may be composed of a material having a particularly high reflectivity and/or have a coating having a particularly high reflectivity. Furthermore, the reflective fibers may have a color with a particularly high reflectivity, such as white, beige or light gray. The reflectivity preferably relates to the wavelength range of visible light. The wavelength range may be about 400 to 800 nm. Furthermore, the reflectivity should be understood such that the reflective fibers should have the reflectivity values listed here, at least in the case of the used wavelength of the light emitted by the optical fibers. For example, if the optical fiber emits light having a wavelength of 500nm or light in the wavelength range of 400 to 800nm, the data on the reflectivity should be understood such that the reflective fiber reflects the light emitted by the optical fiber with the listed reflectivity at least at the wavelength of 500nm or 400 to 800 nm. A minimum effective reflection of the light emitted by the optical fibers should therefore be ensured by the reflective fibers, so that a minimum intensity is reflected and can contribute to an improved luminous capacity of the lighting element.

Furthermore, the cover layer may be made of a flexible material. The flexible material enables or simplifies the bending of the cover layer about the bending axis to form the bending section. In addition, the flexible material increases the freedom of design in the installation, placement and use of the lighting element.

In addition, the cover layer may comprise a plurality of textile fibers. Textile fibres are particularly suitable flexible materials. They are inexpensive to manufacture and their processing is easy to operate. The textile fibers can preferably comprise synthetic materials such as polypropylene, polyamide, polyethylene and/or polyester. However, natural fibers such as animal hair, cotton and/or hemp may also be used as textile fibers. The cover layer may be composed of a nonwoven fabric.

The optical fibers and/or the reflective fibers may be woven into the cover layer, particularly interwoven with a plurality of textile fibers. For example, transverse fibers extending in the transverse direction may be provided. These transverse fibers may be arranged to fasten optical fibers and/or reflective fibers to the cover layer to enable interweaving of the optical fibers, reflective fibers and/or cover layer. The transverse fibres may consist of polyester, polypropylene or polyamide or may comprise one or a combination of these plastics. By weaving fibers into or with the cover layer, the lighting element can be produced particularly simply and economically. In particular, the optical fibers may have different lengths and may be interwoven with the cover layer in different ways to provide the illumination pattern. In addition, the cover layer may comprise a pattern or design arranged to be visible in a state in which the cover layer is not illuminated and/or visible in a state in which the cover layer is illuminated. The transverse fibers may likewise be textile fibers.

Preferably, the optical fibre or fibres are capable of movement relative to the cover layer. This can be achieved, for example, by loosely bundling the transverse fibers in the region of the optical fiber(s). The movement of the optical fiber(s) enables a better flexibility in the transverse direction and a better force distribution upon impact, whereby in particular locally generated stresses on the optical fiber(s) can be reduced. This has the advantage that: the occurrence of damage to the optical fibre(s) can be reduced. The taught flexibility in the lateral direction enables the arrangement of the lighting elements in sharper or more angular curves.

In some embodiments, the optical fibers may be housed in a curved section of the cover layer. The accommodation of the optical fibers in or at the curved sections provides as large a usable solid angle as possible for the light emitted laterally by the optical fibers, which can be emitted directly from the optical fibers onto the cover layer, in such a way that the luminous capacity of the lighting element can be improved. In addition or alternatively, the optical fiber may have a lateral clearance along the covering layer of at least half its diameter. The lateral gap allows a simple bending of the cover layer to form the bending section.

Further, the diameter of the optical fiber may be less than or equal to the diameter of the reflective fiber. The size ratio of the diameter of the optical fiber to the diameter of the reflective fiber may be, for example, at least 1: 1.1, preferably at least 1: 1.25 and/or max 1: 3. preferably a maximum of 1: 2. to improve the stability of the lighting element, reflective fibers with larger diameters may be used. Preferably, the forces act first on the reflective fibers in the event of a crash, as a result of which, in particular, locally occurring stresses on the optical fiber(s) can be reduced. This has the advantage that: the occurrence of damage to the optical fibre(s) can be reduced.

The diameter of the optical fibre may be at least 0.1mm, preferably at least 0.5mm and/or at most 3mm, preferably at most 1 mm. The optical fibers can preferably comprise or consist of polymers such as polymethyl methacrylate (PMMA), Polycarbonate (PC), Polystyrene (PS) and/or glass. However, the optical fibers may also have other optical materials. This enables to achieve a desired light emitting capability at a lower cost.

In some embodiments of the lighting element, a number of optical fibres may be provided. In particular, at least 3, preferably at least 5 and/or at most 31, preferably at most 21 optical fibers are provided, which extend in the longitudinal direction and are arranged to emit light in the transverse direction. From an aesthetic point of view, 11 optical fibres are particularly preferred. Features already described in connection with one optical fibre can also be applied in a similar manner to a number of optical fibres. For reasons of redundancy, these features will not be described in detail here. The optical fibers of the plurality of optical fibers can be constructed in particular identically. As the number of optical fibers used increases, the light emitting capability of the lighting element can be improved. Preferably, the optical fibers are arranged along the covering layer, in particular parallel to the covering layer and/or at equal distances from the covering layer, respectively. In this way a small overall thickness of the lighting element is achieved.

Furthermore, a plurality of reflective fibers may be provided. In particular, at least 2, preferably at least 6 and/or at most 20, preferably at most 10, reflective fibers are provided, which are arranged parallel to the optical fibers and are arranged to reflect the light emitted by the optical fibers. The features already described in connection with one reflective fibre can also be applied in a similar manner to a number of reflective fibres. These features will not be described again here for reasons of redundancy. The reflective fibers can be of structurally identical design. As the number of reflective fibers used increases, the effective reflective surface for reflecting light emitted by the optical fibers can be enlarged. Overall, more emitted light can be reflected by the reflective fibers, thereby increasing the luminous capacity of the lighting element. Preferably, the reflective fibers are arranged along the cover layer, in particular parallel to the cover layer and/or at equal distances from the cover layer, respectively. In this way a small overall thickness of the lighting element is achieved. It is particularly preferred that the reflective fibers are disposed adjacent to and in contact with each other to provide an aperture-tight reflective surface.

Furthermore, a vehicle interior trim part is proposed, which comprises the illumination element described herein and at least one interior trim element. The lighting element is fastened to the interior trim element with a section of the cover layer that is different from the bent section of the cover layer. Furthermore, the lighting element can be fastened between two interior trim elements in a rolled-on manner (paneling) and connect these interior trim elements in particular to one another. The fastening of the lighting element to one or more interior trim parts can be effected, for example, by sewing, fusing, ultrasonic welding, vibration welding or gluing. The lighting element can project from the interior trim element in curved sections, for example project into the vehicle passenger compartment, and can illuminate the vehicle passenger compartment with a suitable luminous power. In addition, the vehicle interior having the illumination element can provide a line-type illumination surface having a small and thick line and a narrow line and improved light-emitting capability.

The vehicle interior trim component may further include an illuminator coupled to the at least one optical fiber of the lighting element for coupling light into the at least one optical fiber of the lighting element. The illumination member may comprise a laser diode or an LED (light emitting diode).

Furthermore, a method for producing a lighting element for a vehicle passenger compartment is proposed, comprising the following steps: providing at least one optical fiber, at least one reflective fiber, and a light-transmissive cover layer; the optical fibers and the reflective fibers are arranged on the cover layer such that they run parallel to one another and in particular in the longitudinal direction; the cover layer is bent around a bending axis extending in a longitudinal direction, wherein the optical fibers are arranged to emit light in a transverse direction perpendicular to said longitudinal direction, and the reflective fibers are arranged to reflect the light emitted by the optical fibers.

Furthermore, a semifinished product for producing a lighting element can be provided, which is suitable for a vehicle passenger compartment and which has: at least one optical fiber, at least one reflective fiber, and a light-transmissive cover layer that is at least partially bendable about a bending axis extending along a longitudinal direction. The optical fibers and the reflective fibers may be arranged on the cover layer such that the optical fibers and the reflective fibers are parallel to each other in the longitudinal direction and/or the bending axis to optical fiber spacing is smaller than the bending axis to reflective fiber spacing.

The features listed for the lighting element or the semi-finished product can be transferred accordingly to the method for manufacturing the lighting element and vice versa.

Drawings

The figures show a plurality of embodiments of a lighting element of the type proposed here and of a method proposed here and two embodiments of a vehicle interior trim part with one lighting element of the type proposed here and of a method proposed here and are explained in detail by the following description. In the drawings:

fig. 1A is a cross-sectional view of a first embodiment of a semi-finished product for manufacturing a lighting element;

FIGS. 1B, 1C are cross-sectional views of various embodiments of a lighting element fabricated from the semi-finished product of FIG. 1A;

fig. 2A is a cross-sectional view of a second embodiment of a semi-finished product for manufacturing a lighting element;

FIGS. 2B and 2C are cross-sectional views of various embodiments of a lighting element fabricated from the semi-finished product of FIG. 2A;

fig. 3A is a cross-sectional view of a third embodiment of a semi-finished product for manufacturing a lighting element;

FIGS. 3B and 3C are cross-sectional views of various embodiments of a lighting element fabricated from the semi-finished product of FIG. 3A;

fig. 4A is a cross-sectional view of a fourth embodiment of a semi-finished product for manufacturing a lighting element;

FIGS. 4B and 4C are cross-sectional views of embodiments of lighting elements fabricated from the semi-finished product of FIG. 4A;

FIGS. 5A, 5B are cross-sectional views of various embodiments of interior trim pieces for a vehicle;

fig. 6 is a perspective top view of the vehicle interior trim piece of fig. 5A having an illumination element.

Several embodiments of a lighting element and two embodiments of a vehicle interior trim part are shown with the aid of the figures. The lighting element and the vehicle interior part including the lighting element can realize line type lighting with small line thickness, narrow line and improved luminous capability. In the subsequent figures and the description that follows, the same reference numerals are used for the repeated features. In order to avoid repetition, the description of the repetitive features will not be repeated hereinafter.

Detailed Description

Fig. 1A shows a cross-sectional view of a first embodiment of a semi-finished product for manufacturing the lighting element 1 proposed herein. The semifinished product for producing a lighting element 1 suitable for a vehicle passenger compartment has at least one optical fiber 2, at least one reflective fiber 3 and a light-transmitting cover layer 4. The light-transmitting cover layer 4 can be curved at least partially about a bending axis 5 extending in a longitudinal direction (perpendicular to the direction of extension of the picture in fig. 1A). The optical fiber 2 and the reflective fiber 3 are disposed on the cover 4 such that the optical fiber 2 and the reflective fiber 3 are parallel to each other in the longitudinal direction, and the distance from the bending axis 5 to the optical fiber 2 is smaller than the distance from the bending axis 5 to the reflective fiber 3. The corresponding spacing is exemplarily drawn with dashed lines in fig. 1A. The optical fiber 2 is arranged closer to the curved first section 6 of the cover layer 4 and the bend of the cover layer 4 formed by the curved first section 6 than the reflective fiber 3. The optical fibres 2 and the reflecting fibres 3 are arranged in particular on one side of a line of minimum spacing connecting the bending axis 5 and the covering layer 4. The optical fibre 2 is arranged between the reflective fibre 3 and the bending axis 5.

The optical fibers 2 are configured as side-emitting optical fibers for emitting light in a suitable manner from the sides in a transverse direction extending perpendicular to the longitudinal direction. The laterally emitted light is schematically shown in fig. 1A and in subsequent figures by arrows pointing away from the optical fiber 2. The reflective fiber 3 is arranged to reflect light emitted by the optical fiber 2. This is schematically illustrated in fig. 1A and in the following figures by means of arrows going from the optical fibers 2 to the reflective fibers 3 and then from the reflective fibers 3 to the cover layer 4.

In the method for manufacturing a lighting element 1 proposed herein, a cover layer 4 of a semi-finished product for manufacturing the lighting element 1 is bent around a bending axis 5 to obtain a lighting element 1 of the type proposed herein. Fig. 1B, 1C, 2B, 2C, 3B, 3C each show an exemplary embodiment in which the lighting element 1 produced from the semifinished product has two different bending angles.

As shown by way of example in fig. 1B, 1C, the illumination element 1 proposed here has a first section 6 which is curved about a bending axis 5, wherein the cover layer 4 encloses both the optical fibers 2 and the reflective fibers 3. Due to the curved first section 6 it is possible to: light emitted laterally by the optical fiber 2 can be emitted through the light-transmitting cover layer 4. This is illustrated in particular in fig. 1C, 2C, 3C and 4C by means of arrows emanating from the optical fiber/fibers 2. It is thus possible to provide more light emitted by the optical fibre 2 for illuminating the space on the other side of the cover layer 4. The luminous capacity of the lighting element is thus improved. In this way, a lighting element 1 can already be realized with only one optical fiber 1, the luminous power of which is at least suitable for decentralized illumination.

The lighting element 1 at the same time has a small thickness which is substantially determined by the diameter of the light-conducting fiber 2 or of the reflecting fiber 3 (see in particular fig. 1C). The diameter of the optical fibre 2 is for example 1 mm. The diameter of the reflective fibers 3 is, for example, 1.25 mm. With the proposed lighting element 1, therefore, a very narrow emission area, in particular a linear emission area with a linear thickness of less than 4mm, preferably less than 2mm, can be achieved, while maintaining or at least maintaining as large as possible the luminous capacity of the lighting element. By the reflective fibers 3 having a larger diameter than the diameter of the optical fibers 2, an improved stability of the lighting element 1 is achieved. In addition, forces can therefore act first or substantially on the reflective fibers 3 in the event of a crash and can therefore be damped, as a result of which the stresses occurring locally on the optical fibers 2 in the event of a crash can be reduced. This has the advantage that: the occurrence of damage to the optical fiber 2 can be reduced.

The bent first section 6 of the cover layer 4 may be bent over a bending angle of at least 45 degrees, at least 135 degrees or preferably 180 degrees. Fig. 1B, 2B and 3B exemplarily show a lighting element 1 having first segments 6 each bent by a bending angle α of 90 degrees. Compared to the lighting elements 1 of fig. 1C, 2C, 3C and 4C, in which the cover layer 4 of the lighting element 1 is bent in the bent first section 6 by a bending angle α of 180 degrees, respectively, it can be seen that with increasing bending angle, at least in the range from zero to 180 degrees, the overall thickness of the lighting element 1 can be reduced, and the usable light emission solid angle of the light-guiding fiber 2 can be enlarged and the luminous capacity of the lighting element 1 can be improved. As shown in fig. 1C, 2C, 3C and 4C in particular, the cover layer 4 can be folded such that two further

second sections

7, 8 of the cover layer 4 are arranged parallel to one another. In particular, the further

second sections

7, 8 rest on the optical fiber/fibers 2 and the reflective fiber/fibers 3. In this way, a particularly small thickness of the lighting element 1 is achieved.

The light emitted by the optical fibre 2 is emitted at the front side of the cover layer 4 and is used to illuminate the cover layer 4 of the lighting element at the front side. The optical fibers 2, the reflective fibers 3 and the bending axis 5 are arranged on the backside of the cover layer 4. By arranging the bending axis 5 on the rear side, the cover layer 4 is bent towards its rear side, so that the front side of the cover layer 4 is used as the viewing side with as large a viewing area as possible. Furthermore, this arrangement provides a large light emission solid angle of the optical fiber 2 that can be used for front-side illumination, thereby improving the luminous capacity of the lighting element 1. Furthermore, the cover layer 4 provides protection against external influences, such as mechanical impacts, in case the optical fibers 2, the reflective fibers 3 and the bending axis 5 are arranged at the back side.

Fig. 1B shows exemplary positions of the optical fibers 2 and the reflective fibers 3 on the backside of the cover layer 4. In this way, it can be provided that the

optical fibers

2, 2 ', 2 ″ and the

reflective fibers

3, 3', 3 ″ are arranged centrally with respect to the further

second sections

7, 8 of the cover layer 4 (circles drawn with dashed lines) or are arranged adjacent to one or the other of the two further

second sections

7, 8 of the cover layer (circles drawn with solid lines or circles drawn with dotted lines). Thus enabling a wide variety of lighting features.

The reflective fiber 3 is a white textile fiber having a reflectivity of almost 1. However, it can also consist of other materials, be provided with a coating or have other colors, which have a reflectivity of at least 0.1, preferably at least 0.3, particularly preferably at least 0.6. The reflective fiber 3 is arranged to reflect light emitted by the optical fiber 2 over the entire wavelength range from about 400 to 800nm of visible light with a reflectivity of, for example, 0.8, but preferably still slightly higher than 0.8. This can be achieved: the light emitted by the optical fibers is reflected as well as possible by the reflective fibers 3, so that as much light as possible emitted by the optical fibers 2, that is to say directly emitted and indirectly emitted by reflection on the reflective fibers 3, is provided on the front side of the lighting element 1.

Compared to the embodiment of the proposed lighting element 1 shown in fig. 1A to 1C, fig. 2A to 2C show embodiments of the lighting element 1, the differences between these embodiments essentially being in the arrangement of the optical fibers 2, the reflective fibers 3 and the bending axis 5. In contrast to the arrangement shown in fig. 1A to 1C, the bending axis 5 in the exemplary embodiment shown in fig. 2A to 2C is arranged between the optical fiber 2 and the reflective fiber 3, wherein the distance between the optical fiber 2 and the bending axis 5 is in turn smaller than the distance between the reflective fiber 3 and the bending axis 5. The optical fibers 2 are also arranged closer to the curved first section 6 of the cover layer 4 and the crimp of the cover layer 4 formed by the curved first section 6 than the reflective fibers 3. In the embodiment shown in fig. 2A to 2C, the reflective fibers 3 are also arranged to reflect light emitted by the optical fibers 2 in the direction of the cover layer 4. The reflected light contributes additionally to the luminous capacity of the lighting element 1.

The lighting element 1 presented herein may comprise a number of optical fibers 2 and/or a number of reflective fibers 3. For example, at least 3, preferably at least 5 and/or at most 21, preferably at most 11 optical fibers 2 and/or reflective fibers 3 can be provided, which extend in the longitudinal direction. In contrast to the described embodiments of the lighting element 1 presented here, fig. 3A to 3C show exemplary embodiments of a lighting element 1 with three optical fibers 2 and two reflective fibers 3, while fig. 4A to 4C show exemplary embodiments of a lighting element with 11

optical fibers

2 and 8 reflective fibers 3. The optical fibres 2 and the reflecting fibres 3 are arranged parallel to the cover layer 4 and at equal distances from the cover layer. In addition, the optical fibers 2 are arranged along the cover layer 4 and between the respective reflective fibers 3. The reflective fibers 3 are arranged in particular on both sides of the bending axis 5 to provide a reflective surface on both sides. With this enlarged reflective surface, the light emitted by the optical fiber 2 can be reflected back to the cover layer 4 with greater intensity and make a greater additional contribution to the luminous capacity of the lighting element 1. This is illustrated in particular in fig. 3B, 3C and 4C by the angled arrows. For example, fig. 3B and 3C show the reflection of light emitted by the respective two optical fibers 2 on the reflective fiber 3.

By accommodating one of the optical fibers 2, in particular the centrally arranged optical fiber 2, in the curved first section 6 of the cover layer 4, in particular in the central region of the curved first section 6, it is possible to utilize the particularly large solid angle of the light emitted laterally by this optical fiber 2 for emitting the light through the cover layer 4 and for increasing the luminous power of the lighting element 1. Fig. 4B and 4C show: the central optical fibre 2 can have a lateral clearance along the cover layer 4 with respect to two adjacent optical fibres 2, which is at least half the diameter of the optical fibres 2. The lateral gap allows a better flexibility of the cover layer 4 in the region of the curved first section 6. The remaining optical fibers 2 are preferably arranged next to one another as shown in fig. 4B.

Preferably, some of the reflective fibers 3 and/or optical fibers 2 may be arranged in pairs in the further

second sections

7, 8 with equal spacing from the bending axis 5. Fig. 3A shows such a pair of reflective fibers 3 and a pair of optical fibers 2, respectively. And figure 4A shows an example with four pairs of reflective fibres 3 and five pairs of optical fibres 2. The cover layer 4 can be folded, for example, in such a way that the

fibers

2, 3 arranged in the two further

second sections

7, 8 are each located indirectly on the respective other of the further

second sections

7, 8. The pairs of

fibres

2, 3 rest against each other, as exemplarily shown in fig. 3C, 4C. One or more pairs of reflective fibres 3 are arranged in contact with each other and provide a closely apertured reflective surface which reflects light emitted by the optical fibres 2, but not in the direction of the cover layer 4, towards the cover layer. The reflected light may be used as an additional contribution to the light emitting capabilities of the lighting element 1. By increasing the number of optical fibers 2 used, the luminous capacity of the lighting element 1 is increased. In addition, the light coupling efficiency of light into the illumination element 1 is improved due to the expanded etendue based on the increase in the number of optical fibers 2 used.

It can further be seen that even if a number of

fibers

2, 3 are used, the total thickness of the lighting element 1 is substantially determined by the sum of the two diameters of the reflective fibers 3 or the two diameters of the optical fibers 2. This enables a compact construction with a small thickness of the lighting element 1 of 4mm or less, in particular 3mm or less, and at the same time provides a high luminous capacity of the lighting element 1.

In some of the embodiments, the cover layer 4 is made of a flexible material. The flexible material enables or simplifies the bending of the cover layer 4 about the bending axis 5 to form the bent first section 6. Preferably, the cover layer 4 comprises a number of textile fibers 9, which are shown by way of example in fig. 4B, but are not limited to the embodiments shown there. Textile fibres are particularly suitable flexible materials. They are inexpensive to manufacture and their processing is easy to operate.

The textile fibers 9 of the cover layer 4 have a smaller diameter than the optical fibers 2 and the reflective fibers 3. The smaller diameter of the textile fibers 9 of the cover layer 9 reduces the total thickness of the lighting element 1. In addition, the cover layer 4 is more flexible and more easily bendable. As an alternative, more optical fibers 2 can be used with the saved space, in order to improve the emission capability of the lighting element 1 while the total thickness of the cover layer 4 is unchanged.

The optical fibres 2 and the reflecting fibres 3 are woven into a cover layer 4. The transverse fibers 10 extending in the transverse direction shown in fig. 4B are woven together with the optical fibers 2, the reflective fibers 3 and the cover layer 4, for example, by means of a jacquard pattern. In this way, a particularly simple and economical production of the lighting element 1 is achieved.

In the exemplary embodiment shown in fig. 4B, the

fibers

2, 3 have the same length and are generally each of identical design. However, it is also possible to provide optical fibers 2 of different lengths or optical fibers 2 that are interwoven with the cover layer 4 in a different manner, for example to form an illumination pattern. In particular, the reflective fiber 3 may be longer than the optical fiber 2. In addition, the cover layer 4 may comprise a pattern or a design which is, for example, permanently visible, that is to say visible in the unlit state of the cover layer 4, or alternatively only visible when the cover layer 4 is illuminated by the optical fiber(s) 2.

Fig. 4C shows that the lighting element 1 may comprise an adhesive layer 14. The adhesive layer 14 may be applied to the optical fibres 2 and the reflective fibres 3 of the semi-finished product shown in figure 4A. In particular when folding over the cover layer 4 for producing the lighting element 1 shown in fig. 4C, an adhesive layer 14 can be arranged between the pairs of optical fibers 2 and reflective fibers 3 and preferably adheres them to one another. The adhesive layer 14 prevents the folded-over covering layer 4 from moving back or flipping back and at the same time increases the stability of the lighting element 1. The adhesive layer 14 may also be provided on the cover layer 4, for example.

Alternatively, embodiments can also be provided in which the optical fibers 2 are designed to be movable relative to the cover layer 4. This can be achieved, for example, by loosely bundling the transverse fibers 10 in the region of the optical fibers 2. The possibility of movement of the optical fibre 2 enables greater flexibility and better force distribution upon impact.

Fig. 5A and 5B show a cross-sectional view of the proposed vehicle interior trim part 100, which comprises the illumination element 1 described here and one interior trim element 11 (fig. 5A) or two interior trim elements 11, 11' (fig. 5B). The vehicle interior trim part 100 is not limited to the embodiment of the lighting element 1 shown here. The lighting element 1 is only illustrated as the lighting element 1 of fig. 4C to illustrate the operation principle and advantages of the interior trim part 100 of the vehicle.

The lighting element 1 is fastened to the interior trim element 11 with a section of the cover layer 4 that is different from the curved first section 6 of the cover layer 4 (fig. 5A), or is fastened between two interior trim elements 11, 11' in a rimmed manner (fig. 5B). By virtue of the rolled-on fastening of the lighting element 1, the interior trim elements 11, 11 'are connected to one another, in such a way that, for example, conventional seams for connecting the interior trim elements 11, 11' can be replaced or at least concealed or concealed from view by the user.

In the present embodiment of the vehicle interior trim part 100, the lighting element 1 is sewn onto one or more interior trim parts 11, 11' (see reference numeral 12). However, fastening can also be effected, for example, by fusing or bonding. In other embodiments (not shown), the lighting element 1, in particular the portion with the reflective fibers 3, is arranged in a recess of the vehicle interior trim part 100. The lighting element 1 protrudes with a curved first section 6 from one or more interior elements 11, 11'. Depending on the fastening, the lighting element 1 can project over its entire length, that is to say for example 10mm (fig. 5A) or only partially (fig. 5B), for example from one or more interior trim parts 11, 11'. In the case of a partially convex lighting element 1, this lighting element 1 can be inserted and fastened in a sunken cavity of the interior trim part 11 or between two interior trim parts 11, 11'. In particular, the lighting element 1 may be sunk in a section comprising the reflective fibers 3. For example, the lighting element 1 protrudes about 5mm from one or more interior trim pieces 11, 11'. For example, the lighting element 1 projects into the vehicle passenger compartment and provides illumination of the vehicle passenger compartment with a suitable luminous power. In particular, narrow, line-shaped illumination surfaces with a line thickness of less than 4mm, preferably less than 3mm, with improved luminous efficacy can be achieved in this case.

Fig. 6 illustrates a perspective top view of the vehicle interior trim component 100 shown in fig. 5A. The vehicle interior comprises a lighting element 13 coupled to the lighting element 1. The illuminating element 13 comprises a laser diode or an LED (light emitting diode). Light is coupled into one or all of the optical fibres 2 of the lighting element 1 by means of the illumination means 13 to enable illumination of the lighting element 1. Although fig. 6 shows the vehicle interior part 100 shown in fig. 5A, it goes without saying that the embodiment of the vehicle interior part 100 shown in fig. 5B can likewise have, for example, an illumination part 13.

Claims

1. Lighting element (1) for a vehicle passenger compartment, having:

at least one optical fiber (2) extending in a longitudinal direction and arranged to emit light in a transverse direction perpendicular to said longitudinal direction,

at least one reflective fibre (3) arranged parallel to the optical fibre (2) and arranged to reflect light emitted by the optical fibre (2), and

a light-transmitting cover layer (4) which surrounds the optical fibers (2) and the reflective fibers (3), wherein the cover layer (4) has a first section (6) which is curved about a bending axis (5) extending in the longitudinal direction.

2. A lighting element (1) according to claim 1, characterized in that: the cover layer (4) is bent in such a way that a bending angle (alpha) of the bent first section (6) of the cover layer (4) about the bending axis (5) is at least 45 degrees.

3. A lighting element (1) according to claim 2, characterized in that: the cover layer (4) is bent in such a way that a bending angle (alpha) of the bent first section (6) of the cover layer (4) about the bending axis (5) is at least 135 degrees.

4. A lighting element (1) according to claim 3, characterized in that: the cover layer (4) is bent in such a way that a bending angle (alpha) of a bent first section (6) of the cover layer (4) about the bending axis (5) is 180 degrees.

5. A lighting element (1) according to any one of claims 1 to 4, characterized in that: the cover layer (4) has two further second sections (7, 8) extending on both sides of the bending axis (5) and is folded such that the fibers arranged in one of the further second sections (7, 8) rest on the other of the further second sections (7, 8) and/or on the fibers arranged in the other of the further second sections (7, 8).

6. A lighting element (1) according to any one of claims 1 to 4, characterized in that: the reflective fibers (3) have a reflectivity of at least 0.1.

7. A lighting element (1) according to claim 6, characterized in that: the reflective fibers (3) have a reflectivity of at least 0.3.

8. A lighting element (1) according to claim 7, characterized in that: the reflective fibers (3) have a reflectivity of at least 0.7.

9. A lighting element (1) according to any one of claims 1 to 4, characterized in that: the cover layer (4) is made of a flexible material.

10. A lighting element (1) according to claim 9, characterized in that: the cover layer (4) comprises a plurality of textile fibers (9), and the optical fibers (2) and/or the reflective fibers (3) are woven into the cover layer (4).

11. A lighting element (1) according to claim 10, characterized in that: the optical fibers (2) and/or the reflective fibers (3) are interwoven with the plurality of textile fibers (9).

12. A lighting element (1) according to any one of claims 1 to 4, characterized in that: the optical fiber (2) is accommodated in a curved first section (6) of the cover layer (4).

13. A lighting element (1) according to claim 12, characterized in that: the optical fiber (2) has a lateral clearance along the covering layer (4) of at least half the diameter of the optical fiber.

14. A lighting element (1) according to any one of claims 1 to 4, characterised by at least 3 and/or at most 31 light-conducting fibres (2) extending in the longitudinal direction and arranged to emit light in the transverse direction.

15. A lighting element (1) according to claim 14, characterized by at least 5 optical fibers (2).

16. A lighting element (1) according to claim 15, characterized by a maximum of 21 optical fibres (2).

17. Vehicle interior trim part (100) with a lighting element (1) and an interior trim element (11) according to any one of claims 1 to 16, characterized in that: the lighting element (1) is fastened to the interior element (11) in a different section of the cover layer (4) than the first curved section (6) of the cover layer (4).