Optical element of a lighting arrangement for a motor vehicle interior

Abstract

The invention relates to an optical element (2) of a lighting arrangement (1) for an interior of a vehicle. The optical element (2) comprises a substantially planar light-permeable optical body (2a) having a front side which is substantially flat at least in some regions and having a rear side which lies opposite the front side and is structured at least in some regions, such that a lighting pattern can be produced on the front side when the rear side is illuminated with substantially diffuse light. The structured rear side comprises a number of structure elements, which are non-uniformly spaced apart in at least one lateral direction, for generating a substantially periodic lighting pattern in the at least one lateral direction. The invention further relates to a lighting arrangement (1) and to a vehicle having an interior, wherein at least one lighting arrangement (1) is implemented in the interior.

Description

[0001] Description

[0002] OPTICAL ELEMENT OF A LIGHTING ARRANGEMENT, LIGHTING ARRANGEMENT FOR THE INTERIOR OF A VEHICLE, AND THE VEHICLE HAVING A LIGHTING ARRANGEMENT

[0003] The present disclosure relates generally to lighting arrangements. In particular, the present disclosure relates to an optical element of a lighting arrangement, a lighting arrangement for the interior of a vehicle, and a vehicle comprising the lighting arrangement.

[0004] Optical elements for lighting arrangements, as well as lighting arrangements incorporating optical elements, are known. Lighting arrangements for vehicle interiors are also known, designed as functional and / or decorative lighting arrangements, which can be arranged differently within the vehicle interior depending on their intended purpose. To ensure that the lighting arrangements meet specific design and / or functional requirements, various optical elements are used to generate lighting patterns. For example, lighting arrangements with optical elements in the form of translucent cover plates of locally variable thickness are known. Due to this locally variable thickness, lighting patterns can be generated using such optical elements when, for example, they are backlit with diffuse light.With sufficiently high diffusivity and uniformity of the incident light, the luminous pattern is primarily determined by the intensity variation or by the optical structure of the optical element. Non-ideal conditions, insufficient diffusivity, or insufficient uniformity of the incident light can lead to undesirable optical effects, which can be noticeably disruptive in the luminous patterns.

[0005] One object of the present invention is to provide an optical element and a lighting arrangement for the interior of a vehicle for generating precise lighting patterns.

[0006] Following a first aspect, the above problem is solved using an optical element of a lighting arrangement for a vehicle interior. The optical element comprises a substantially planar, translucent optical body with a front surface that is at least partially flat and a rear surface that is at least partially structured, opposite the front surface. This structure allows a luminous pattern or a visually perceptible luminous pattern to be created when the rear surface is illuminated with substantially diffuse light on the front surface. In particular, the structured rear surface of the optical body can be designed such that light rays traveling in the same direction and arriving at different points on the rear surface can experience different degrees of refraction at the rear surface of the optical body.Thus, the light rays entering the flat, translucent body are refracted differently by the optical structure, resulting in bright or brighter and dark or darker areas on the front surface of the optical body. These bright or dark areas can, in particular, create a luminous pattern on the front of the optical body, which can be used, for example, for decorative or accent lighting in vehicle interiors.

[0007] The structured back surface of the optical element comprises a number of structural elements spaced unevenly in at least one lateral direction to generate a luminescence pattern that is essentially periodic in that at least one lateral direction. In particular, the structural elements can be spaced at variable distances from one another along the at least one lateral direction. The optical element enables the suppression of any optical artifacts resulting from insufficient uniformity and / or diffusivity of the illumination of the back surface of the optical element by appropriately adjusting the spacing differences.

[0008] The structural elements can exhibit a substantially monotonically decreasing distance between adjacent structural elements, at least in sections, along at least one lateral direction. In particular, the distances between the structural elements can exhibit a monotonous and / or strictly monotonous pattern, at least in sections, along at least one lateral direction. Due to the monotonous course of the distance between the adjacent structural elements, the luminescence pattern can be visually perceived as an essentially periodic luminescence pattern despite the variation in distance.

[0009] The structured back surface can have a number of structure-free zones between the structural elements, with a width that varies along at least one direction. In particular, the structure-free zones can have a substantially flat, and especially a substantially completely unstructured, surface that can extend between two adjacent structural elements. The structure-free zones can, in particular, serve as intermediate areas with low optical strength to give the luminous structure a characteristic pattern with low light loss. The number of structural elements can include at least two structural elements located close together along at least one lateral direction.By closely arranging the structural elements, it is particularly possible to completely eliminate intermediate areas between the structural elements, for example to compensate for particularly uneven lighting conditions on the back.

[0010] The number of structural elements can, in particular, comprise a number or series of structural elements with a predefined profile, especially along at least one lateral direction. The predefined profile of the structural elements can, in particular, be used to determine the optical effect caused by the structural elements to generate the desired luminous pattern.

[0011] The number of structural elements can comprise a number of structural elements with a variable height or depth along at least one lateral direction. The variable, for example, monotonically decreasing, structural height can be used to determine the strength of the optical effect caused by each structural element, in order to suppress any optical disturbances in the luminous pattern.

[0012] The number of structural elements can include a number of structural elements or laser structures created by means of laser structuring. In particular, the optical body can be laser-shaped in a tool during the forming process, whereby the optical structural elements can also be etched or introduced using another method, for example, mechanical. Structures created by means of laser structuring can have a rough surface in addition to an optical profile, which can create a special lighting effect, especially according to a styling requirement.

[0013] The optical element can be configured, in particular, as a light-emitting window of a lighting device. The light chamber can be configured, in particular, to generate substantially diffuse light for illuminating the rear of the optical element. The lighting device and / or the optical element can be configured, in particular, as part of a lighting arrangement for a vehicle interior, so that interference-free lighting patterns can be generated in the vehicle interior.

[0014] According to a second aspect, a lighting arrangement for the interior of a vehicle is provided. The lighting arrangement comprises an optical element according to the first aspect and at least one light source for generating substantially diffuse light to illuminate the rear of the optical body, such that a luminous structure can be formed on the front of the optical body when the rear is illuminated. Due to the suppression of disturbances resulting from uneven illumination of the rear of the optical body, substantially disturbance-free luminous structures can be achieved on the front of the optical body.

[0015] The lighting arrangement can, in particular, comprise a housing, wherein the at least one light source can be configured to illuminate the housing from the inside. The optical element can be configured as a window or cover element or cover of the housing, so that the back of the optical element can be illuminated by light reflected from an inner wall of the housing. The housing can, in particular, have at least partially diffusely scattering inner walls, so that the scattered light can serve as diffuse light to illuminate the back of the optical element.

[0016] The at least one light source can comprise at least one light engine for generating primary light and at least one diffuser for generating diffuse secondary light, wherein the at least one diffuser can be located at least partially within the housing. The diffuser can be used, in particular, to increase the diffusivity of the light for illuminating the inside of the housing or the rear of the optical body. Due to the high diffusivity of the light incident on the rear of the optical element, any differences in the luminance of the rear can be essentially completely compensated for by the variable parameters, in particular the variable dimensions and / or positioning, of the structural elements.

[0017] According to a third aspect, a vehicle is provided. The vehicle has an interior, in which at least one lighting arrangement according to the second aspect is implemented. Due to the suppression of optical distortions resulting from uneven illumination of the optical body, lighting structures can be generated in the vehicle interior essentially without artifacts.

[0018] The invention will now be explained in more detail with reference to the accompanying figures. The same reference numerals are used in the figures for identical or equivalently functioning parts. Fig. 1 shows a schematic cross-section through a lighting arrangement for the interior of a vehicle according to an exemplary embodiment.

[0019] Fig. 2 shows a perspective sectional view of an optical element according to an exemplary embodiment, and

[0020] Fig. 3 shows a perspective sectional view of the optical element according to Fig.

[0021] 2, specifying further dimensions of the lighting structure.

[0022] Fig. 1 shows a schematic cross-section through a lighting arrangement for the interior of a vehicle according to an exemplary embodiment.

[0023] The lighting arrangement 1 comprises an optical element 2 according to the first aspect. In the illustrated embodiment, the optical element 2 comprises a substantially planar optical body 2a and a support component 2b with an aperture 2c. In particular, the aperture 2c and the support component 2b are formed as one part or in one piece in the illustrated embodiment.

[0024] The optical body 2a is in the form of a tinted, translucent cover plate with a substantially flat or smooth front or outer surface and a structured back surface opposite the front. The front or outer surface of the optical body 2a is at least partially visually perceptible to vehicle occupants under normal operating conditions.

[0025] The support component 2b and the aperture 2c are essentially opaque, whereby the aperture 2c may be designed to prevent direct light exposure to the back of the optical body 2a.

[0026] The lighting arrangement 1 further comprises a lighting unit 3 with a light guide 3a for generating primary light and a housing 4 essentially in the form of an elongated profile with an essentially white, diffusely light-reflecting back wall.

[0027] The lighting unit 3 can comprise one or more light sources, in particular LED (light-emitting diode) light sources, for generating the primary light. The light guide 3a can be configured to couple the light generated by the lighting unit 3 into the housing 4. In the illustrated embodiment, the light guide 3a is elongated and runs partially, substantially along one longitudinal side of the housing 3, within the housing 3. The light guide 3a can be configured as a clear light guide and / or have optical structures for scattering the light exiting the light guide 3a. A diffuser can also be connected downstream of the light guide 3a for diffusely scattering the light exiting the light guide 3a. In particular, the diffuser can be integrated into the lighting arrangement 1 adjacent to the light guide 3a.By means of the optical structures and / or the additional diffuser, the diffusivity of the light arriving on the rear wall of the housing 3 can be increased so that the back of the optical body 2a can be illuminated particularly evenly.

[0028] The translucent optical body 2a is designed such that illuminating the back of the optical body 2a with substantially diffuse light produces a luminescence on the front of the optical body 2a with a striped pattern of alternating light and dark stripes. In particular, the translucent optical body 2a has a wave-like structure on its back side with substantially periodically alternating trough and crest regions. In the illustrated embodiment, the optical body 2a also has a wedge-shaped, upwardly tapered cross-section with a minimum thickness d mat the upper end and with a maximum strength d ma x at the bottom.

[0029] The aperture 2c can be configured, in particular, to modify the illuminance distribution on the rear surface of the optical body 2a. For example, the aperture 2c can be configured to shade a portion of the light emitted by the light guide 3a and / or to absorb a portion of the light scattered from the rear wall of the housing. In particular, the aperture 2c can have a surface that is darker than the rear wall of the housing 3. For example, the aperture 2c or the housing insert 2b can be made of a darker material or have a dark paint and / or lacquer coating. In some embodiments, the housing 3 is made of a white plastic and the aperture 2c or the housing insert 2b is made of a dark plastic.

[0030] In the illustrated embodiment, the aperture 2c has a substantially planar shape, with one end of the aperture 2c resting close to the rear of the optical body 2a or the cover and a second, or free, end opposite the first end pointing away from the rear. In different embodiments, the aperture 2c can have different shapes and / or dimensions. For example, the aperture 2c can extend substantially over the entire length of the housing 3, so that the illuminance distribution over the rear of the cover can be modified along its entire length. Furthermore, the aperture 2c can be used to shade the optical body 2a from direct illumination by the light emitted by the light guide 3a over its entire length.

[0031] The lighting arrangement 1 can be designed, in particular, as part of a lighting assembly that may include further functional and / or decorative components for interior lighting and / or exterior lighting of the vehicle. For example, the lighting arrangement 1 can be designed as part of a dashboard assembly and / or as part of an exterior lighting assembly of the vehicle.

[0032] The orientation or inclination of the lighting arrangement 1 shown in Fig. 1 can essentially correspond to the orientation of the lighting arrangement 1 in the mounted state in the vehicle interior, so that the coverage of vehicle occupants is visually perceptible as a wide rectangular illuminated area with alternating horizontal light and dark stripes.

[0033] Fig. 2 shows a perspective sectional view of an optical element according to an exemplary embodiment. To illustrate the rear surface structure of the optical body 2a, Fig. 2 shows a perspective rear view of the optical element 2, with the right-hand image showing an enlarged detail view of the optical element 2.

[0034] The optical element 2 is designed in the form of a tinted cover plate. As can be seen in the detailed view on the right of the image, the back of the optical body 2a has a series of structural elements in the form of strip-shaped convex optical structures, which are separated from each other by flat surface sections or structure-free zones of variable width. In the illustrated embodiment, the convex optical structures have a substantially cylindrical profile, so that they can function as cylindrical converging lenses.

[0035] In the illustrated embodiment, the optical structures are provided by means of laser structuring or are formed as laser structures. A laser structure with repeating wavy and flat surface sections was applied to the observer-facing rear side of the tinted cover plate. It should be noted that the wavy and flat surface sections are not identical, but change from top to bottom. The depth or structure height of the waves increases, while the flat areas gradually decrease to zero.

[0036] Furthermore, the corrugated sections differ from the flat surfaces in their coarse, rough surface structure compared to the highly polished flat sections. This type of back surface structuring allows for the creation of a lighting effect on the front of the optical body 2a that corresponds to the desired styling.

[0037] The width of the structure-free zones, or the distance between adjacent structural elements, decreases in a lateral downward direction from a maximum distance b. ma x (at the upper edge of the optical body 2a) to a minimum distance b m in (at the lower edge of the optical body 2a) essentially monotonically.

[0038] The flat sections are dimensioned so that their extent decreases steadily from top to bottom with each repetition, reaching a minimum approximately in the center of the cover plate. The subsequent laser profile then consists exclusively of wave-like components or structural elements with surface roughness, without any flat segments.

[0039] As can be seen in the overall representation on the left of the image, the distance between the structural elements decreases from top to bottom to zero, so that the structural elements lie close together in a lower region of the optical body. The continuous reduction of the planar sections to zero (approximately in the middle of the height profile) results in a very harmonious transition to the lower part, which is unobtrusive to the viewer. This avoids the visibility of the luminance maxima in the back illumination and the contours of the support component or aperture. In particular, featureless zones are completely eliminated in the lower region of the optical body 2a, which essentially suppresses artifacts in the illumination pattern caused, for example, by contrast transitions at the aperture 2c.Without this variation in distance, the continuously repeating, constant flat sections (without surface roughness) on the side of the optical body 2a facing away from the observer could cause local luminance maxima and the contours of the aperture 2c to be clearly visible in the lower region of the illumination area. Reducing the distance between the structural elements thus avoids this and significantly improves the perceived quality of the illumination arrangement. Fig. 3 shows a perspective sectional view of the optical element according to Fig. 2, indicating further dimensions of the illumination structure.

[0040] As illustrated in Fig. 3, the structural elements of the optical body have different structural heights. In particular, the structural height of structural elements increases from a minimum structural height h. m in (at the upper edge of the optical body 2a) to a maximum structure height hma x (at the upper edge of the optical body 2a) is essentially monotonically off.

[0041] Due to local differences in structure height, the optical strength of structural elements can be varied locally, thereby avoiding and / or largely suppressing any artifacts in the luminescence pattern.

[0042] In particular, varying the structural height or depth of the corrugated sections perpendicular to the illumination surface can be combined with varying the spacing between the corrugated sections to clearly depict the luminescence patterns on the outer surface of the optical body 2a or the cover. This also further enhances the vertical attenuation of the illumination pattern, allowing the use of a darker tint on the cover plate without any loss of luminance in the upper region of the illumination surface.

[0043] Although at least one exemplary embodiment has been shown in the preceding description, various changes and modifications can be made. The embodiments mentioned are merely examples and are not intended to limit the scope, applicability, or configuration of the present disclosure in any way. Rather, the preceding description provides the person skilled in the art with a plan for implementing at least one exemplary embodiment, whereby numerous changes can be made to the function and arrangement of elements described in an exemplary embodiment without departing from the scope of protection of the appended claims and their legal equivalents. Furthermore, according to the principles described herein, several modules or several products can also be combined to obtain additional functions. Reference numeral list

[0044] 1 Lighting arrangement

[0045] 2 optical element

[0046] 2a optical body

[0047] 2b Support component

[0048] 2c Aperture (part of the support component) 3 Lighting unit

[0049] 3a Optical fiber

[0050] 4 cases

Claims

Claims 1. Optical element of a lighting arrangement (1) for an interior of a vehicle, wherein the optical element (2) is a substantially planar translucent optical body (2a) with a front side that is at least partially substantially flat and with a rear side opposite the front side that is at least partially structured, such that when the rear side is illuminated with a substantially diffuse light on the front side, a luminous pattern can be created, wherein the structured rear side has a number of structural elements spaced unevenly apart in at least one lateral direction to create a luminous pattern that is substantially periodic in at least one lateral direction.

2. Optical element according to claim 1, wherein the structural elements have a distance between adjacent structural elements that decreases monotonically at least sectionally along the at least one lateral direction.

3. Optical element according to claim 1 or 2, wherein the structured back side has a number of structure-free zones between the structural elements with a width that varies along at least one direction.

4. Optical element according to one of the preceding claims, wherein the number of structural elements comprises at least two structural elements lying close together along the lateral direction.

5. Optical element according to one of the preceding claims, wherein the number of structural elements comprises a number of structural elements with a predefined profile.

6. Optical element according to one of the preceding claims, wherein the number of structural elements comprises a number of structural elements with a structural height that varies along at least one lateral direction.

7. Optical element according to any one of the preceding claims, wherein the number of structural elements comprises a number of structural elements produced by means of laser structuring, in particular in the tool, and / or mechanically.

8. Optical element according to any one of the preceding claims, wherein the optical element (2) is configured as a light exit window of a lighting device (1).

9. Lighting arrangement for the interior of a vehicle, comprising an optical element (2) according to one of the preceding claims and at least one light source for generating a substantially diffuse light for illuminating the rear of the optical body (2a), so that when the rear of the optical body (2a) is illuminated, a luminous structure can be created on the front of the optical body (2a).

10. Vehicle, wherein the vehicle comprises an interior space and wherein at least one lighting arrangement (1) according to claim 9 is implemented in the interior space.

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