EP4348101A1 - Lighting device with light distributing body - Google Patents

Abstract

As part of the invention, a lighting device is provided, in particular for lighting an interior, said lighting device having a lighting means (3) and a light distributing body (1) with a light coupling surface (11) and a translucent light outlet region (12). The light distributing body (1) is designed to dispense a first part of the light which is emitted by the lighting means (3) and which is introduced into the light distributing body (1) via the light coupling surface (11) in a directed manner and to control a second part of the introduced light by means of the light distributing body (1) such that the light exits in a diffused manner substantially via the entire light outlet region (12) of the light distributing body (1).

Description

MEISSNER BOLTE M/OCC-176-PC May 30, 2022

Lighting device with light distribution body

DESCRIPTION

The present invention relates to a lighting device with a light distribution body according to the subject matter of claim 1.

Lighting devices with different emission characteristics are known, each of which is suitable for lighting purposes in different applications. For example, lighting devices are known which have a diffuse emission characteristic. Such lighting devices are suitable for evenly illuminating a room over a large area. On the other hand, lighting devices are known which are designed to emit directed light, such as spotlights or spotlights. A limited spatial area can be specifically illuminated with such lighting devices.

In many cases it is desirable to use both radiation characteristics simultaneously to illuminate a room, for example in work rooms with one work station. There it is desirable to illuminate the room evenly and at the same time to be able to provide increased illumination of the workplace. Likewise, in order to create a pleasant room atmosphere, it is often desirable to combine diffuse lighting of the room with directed lighting of certain areas of the room.

Various lights are known in the prior art that combine different light sources with different emission characteristics for the simultaneous generation of diffuse and directed light. For example, DE 20 2016 102 638 U1 discloses a hybrid light that has at least one LED light source for emitting a directed luminous flux and at least one flat OLED light source for emitting a diffuse luminous flux. There MEISSNER BOLTE M/OCC-176-PC

2 the hybrid light requires separate light sources to provide the different beam characteristics, the space requirement and the effort in production are increased.

Against this background, the object of the present invention is to specify a lighting device that is suitable for emitting directed and diffuse light. Furthermore, the present invention is intended to specify a lighting device which, despite the possibility of generating directed and diffuse light, is characterized by a structurally simple and compact, space-saving design.

The object is achieved by a lighting arrangement having the features of claim 1. Advantageous developments result from the dependent claims.

The object is achieved in particular by a lighting device, in particular for illuminating an interior, having a lighting means for emitting light and a light distribution body with a light coupling surface and a translucent light exit area, the light distribution body being designed to transmit a first part of the light emitted by the lighting means and via the light in-coupling surface to emit light introduced into the light distribution body in a directed manner, and to scatter a second part of the introduced light by means of the light distribution body such that the light exits diffusely essentially over the entire light exit region of the light distribution body.

An essential idea of the invention is to provide a light distribution body and to configure it in such a way that coupled light that is emitted by a (single) illuminant is partly emitted diffusely and partly directed out of the light distribution body. This achieves a structurally simple and space-saving construction of a lighting device with two emission characteristics, since only one lighting means and one (comparatively compact) light distribution body are required.

The light distribution body fulfills a dual function. A (first) part of the light coupled into the light distribution body is inside the MEISSNER BOLTE M/OCC-176-PC

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Light distribution body so out and preferably directed that this part of the light emerges directed from the light distribution body. The directed component of the coupled-in light preferably exits via a partial area of the light exit area. A (second) part of the light coupled into the light distribution body is scattered or distributed by the light distribution body in such a way that this part of the coupled light is emitted diffusely over essentially the entire light exit area, preferably over the entire light exit area. The diffusely emitted light is preferably emitted both when exiting the surface of the

Light distribution body, which forms the light exit area, scattered, as well as internal reflections inside the light distribution body. Due to the internal reflections, the light is also distributed in the light distribution body.

The light distribution body thus produces a diffuse emission characteristic by scattering one (first) part of the coupled-in light and a directional emission characteristic by emitting the other (second) part of the coupled-in light in a directed manner. According to the invention, the light distribution body is thus designed to emit light that is coupled in via the light coupling surface with an emission characteristic that represents a superimposition of a diffuse emission characteristic and a directed emission characteristic. Advantageously, no separate lighting means or optical elements for modifying the emission characteristic are required to provide this emission characteristic.

The lighting device according to the invention has an emission characteristic that represents a superimposition of a diffuse and a directional emission characteristic. Thus, with the lighting device according to the invention, a room, in particular an interior space, can be illuminated uniformly with a single light source and at the same time a limited area of the room can be illuminated in a targeted manner with the directed light component.

In the context of the present invention, a diffuse light emission or emission characteristic means a spatial emission pattern that has a substantially constant intensity over a large solid angle range, preferably over a solid angle range of 2n sr (steradian) or more. In contrast, denotes a directional MEISSNER BOLTE M/OCC-176-PC

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Light emission or emission characteristics a spatial emission pattern in which the emission is limited to a small solid angle range of less than 2n sr, preferably less than 1 sr. directed light emission is therefore not limited to collimated light emission, but also includes a conical emission pattern with a small emission angle of preferably 45° or less.

According to a preferred embodiment of the invention, the lighting device has a light guide which is designed to guide light emitted by the lighting means to the light coupling surface of the light distribution body. As a result, the lighting means can be arranged at a distance from the light distribution body. This can be advantageous in terms of construction. In addition, the distance between the light source and the light distribution body can be specifically adjusted by the light guide by the length of the light guide being selected accordingly. This can help to modify the emission angle of the directed light component.

Any optical element with which light can be transported within the light guide between a coupling-in surface and a coupling-out surface of the light guide can be used as the light guide. An optical waveguide, for example, can be used as the light guide. Elongated, for example cylindrical or prism-shaped elements made of a transparent material such as glass or a transparent plastic can also be used as light guides, in which the light emitted by the illuminant is coupled in via a base area and is coupled out via the axially distant base area.

Preferably, the light distribution body is formed by a convex body made of a transparent material. The light distribution body preferably has a spherical geometry. The light distribution body is particularly preferably formed by an essentially spherical body. A substantially spherical body is to be understood as meaning a body whose shape deviates only slightly from a spherical shape. For example, the deviation can be present in the form of local flat areas to form the light coupling surface. Likewise are ellipsoids, in which the difference in the length of the semi-axes is significantly smaller than the length MEISSNER BOLTE M/OCC-176-PC

5 of the shortest semi-axis (preferably no length difference between the semi-axes is more than 10% of the length of the shortest semi-axis) is to be understood as essentially spherical in the context of the present description.

In order to ensure the light distribution function inside the light distribution body, it is further preferred that the light distribution body is made of a transparent material, preferably glass or a transparent plastic. The light distribution body is preferably solid (ie without cavities) and preferably consists essentially entirely of the transparent material.

With such a light distribution body, the directed portion of the emitted light can be implemented in a particularly simple manner in terms of construction. A light distribution body which is formed by a solid, essentially spherical body made of a transparent material is particularly preferred. With this configuration, part of the light introduced into the light distribution body is converged by the substantially spherical light distribution body. This part of the coupled-in light emerges from the light-distributing body in a directed manner via a region of the light-emitting surface of the light-distributing body that is opposite the light-coupling surface. The directed part of the emission of the coupled-in light can thus be implemented in a particularly simple manner with a light distribution body that is geometrically compact and easy to produce.

It is preferred here that the essentially spherical light distribution body has a diameter of more than 5 cm, particularly preferably between 5 cm and 50 cm.

According to a further preferred embodiment of the invention, the light exit area of the light distribution body is formed by a frosted surface. Specifically, the light exit area is formed by a frosted surface on a surface of the light distribution body. As a result, a diffuse light exit can be provided over the entire light exit area in a particularly simple manner. The matting of the light exit area can be produced in the usual way by roughening the surface, for example by etching or sandblasting. MEISSNER BOLTE M/OCC-176-PC

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In a preferred embodiment, the light distribution body is formed by a solid, essentially spherical body made of a transparent material, the surface of which is frosted with the exception of the light coupling surface. Because of the spherical shape, a (first) part of the coupled-in light is bundled and exits in a directed manner via a surface area of the light distribution body or a part of the light exit area that is opposite the light-coupling surface. Another (second) part of the coupled light exits diffusely on the frosted surface of the light distribution body (i.e. on the light exit area) and/or is diffusely reflected inside the light distribution body on the frosted surface and then diffusely emitted via the frosted surface.

A lighting device can thus be formed which provides a particularly advantageous and aesthetically pleasing combination of diffuse and directed emission characteristics using only one light source, which is particularly simple and inexpensive to produce and which has a particularly compact structure. It has surprisingly turned out that when using a solid, spherical light distribution body made of a transparent material with a frosted surface as the light exit area, a lighting device is created in which the intensity of the light component that is diffusely emitted by the light distribution body is satisfactory over the entire light exit area has a high intensity that is suitable for uniform and atmospheric lighting, while the directional portion of the emitted light is bright enough to illuminate a limited area of a room like a spot.

It is also preferred that the light input surface is formed by a smooth ground or polished area on the surface of the light distribution body. This facilitates the coupling of light into the light distribution body. The light in-coupling surface can be designed to be essentially planar. Likewise, the light coupling surface can have a convex or concave shape. If an essentially spherical body is used as the light distribution body, a convex-shaped light coupling surface can be formed by polishing a surface area. Alternatively, a planar light coupling surface can be obtained by locally grinding the surface. If the lighting device a MEISSNER BOLTE M/OCC-176-PC

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Having light guides, the surface shape of the light coupling surface preferably corresponds to the surface shape of a light coupling-out surface of the light guide in order to enable the light guide to be seamlessly attached to the light distribution body and thus to improve the light coupling.

The light source is preferably formed by one or more LEDs and is also preferably designed as an LED cluster or LED RGB module. A bright, energy-efficient and compact illuminant with low production costs can thus be provided. The lighting device preferably has exactly one lighting means, which is formed by an (individual) LED or an LED cluster or an LED module. If an LED RGB module is used as the lighting means, the color of the light emitted by the lighting device can be variably adjusted. Due to the internal reflections and scattering, the light distribution body causes a mixture of the light colors that are emitted by the individual LEDs of the LED RGB module. This achieves light emission with a homogeneous color.

In a (further) preferred embodiment, the light distribution body has areas on its surface with a reflective coating that is designed to partially or completely reflect light that propagates inside the light distribution body and impinges on the reflective coating.

By providing a reflective coating in certain areas, the emission characteristics of the light distribution body can be modified in a targeted manner. The emission of directed and/or diffuse light can, for example, be restricted to certain solid angle ranges or can be reduced in a targeted manner in certain ranges. When using a light distribution body with a convex (in particular spherical) shape with a frosted surface, surface areas can be excluded from the light exit area by applying a reflective coating with total reflection in some areas, since no light can exit from the light distribution body in these areas.

According to a (further) preferred embodiment, the lighting device has a holder in which the light distribution body MEISSNER BOLTE M/OCC-176-PC

8 is rotatably mounted at its center. As a result, the direction of the light emitted in a directed manner can be easily adjusted by the user by rotating the light distribution body in the holder. A substantially spherical light distribution body is particularly preferred in this embodiment, since this can be mounted so as to be rotatable about its center point in a structurally simple manner.

It is also preferred that the lighting device has a dome that partially or completely encloses the light distribution body. As a result, the surface of the light distribution body can be protected from dirt and damage. This protection is particularly advantageous in the case of light distribution bodies with a frosted surface, since contamination of the frosted surface can affect the diffusion effect and lead to altered transmission behavior.

According to a preferred development, the dome has surface areas with different degrees of transmission, which are designed to modify the emission characteristics of the light distribution body. At least one surface area preferably has a partially reflective and/or fully reflective coating. According to this development, the emission characteristics of the lighting device can be modified by appropriate design of the dome, without the light distribution body having to be changed. As a result, depending on the application, suitable emission characteristics of the lighting device can be implemented. In addition, an aesthetically advantageous configuration of the lighting device can be implemented.

The invention is also described below with regard to further details, features and advantages, which are explained in more detail with reference to the figures. The features and combinations of features described below, as shown below in the figures of the drawing and described with reference to the drawing, can be used not only in the combination specified in each case, but also in other combinations, without departing from the scope of the invention. MEISSNER BOLTE M/OCC-176-PC

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show here

1 shows a perspective exploded view of a lighting device with a light distribution body according to a preferred exemplary embodiment of the present invention;

FIG. 2 shows an exploded view of the lighting device from FIG. 1 in section; FIG.

FIG. 3 shows a sectional illustration of the lighting device from FIG. 1 in the assembled state; FIG.

FIG. 4 shows a schematic illustration of the emission characteristic that can be achieved with the lighting device according to the exemplary embodiment shown in FIGS. 1 to 3;

FIG. 5 shows an illustration of a variant of the exemplary embodiment shown in FIG. 4 with a schematic representation of the radiation characteristics that can be achieved;

6 shows a graph that qualitatively represents the angular dependency of the emission characteristic that can be generated with the lighting devices shown in FIGS. 4 and 5;

7 shows a schematic sectional view of a lighting device with a light distribution body according to a further preferred exemplary embodiment of the present invention with modified emission characteristics;

8 shows a schematic sectional view of a lighting device with a light distribution body according to a further preferred exemplary embodiment of the present invention with modified emission characteristics;

9 and 10 show a schematic sectional view of a lighting device with a light distribution body according to another preferred embodiment MEISSNER BOLTE M/OCC-176-PC

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Embodiment of the present invention with a holder for the light distribution body;

11 shows a schematic sectional view of a lighting device with a light distribution body according to a further preferred exemplary embodiment of the present invention with a dome;

FIG. 12 is an illustration of a variant of the embodiment shown in FIG.

The figures are only of a schematic nature and serve exclusively for understanding the invention. Identical or similar elements are provided with the same reference symbols in the description of the exemplary embodiments.

1 shows a perspective exploded view of a lighting device according to a preferred embodiment of the present invention. The lighting device has a lighting means 3, a light guide 2 and a light distribution body 1 as main components.

The light source 3 is preferably formed by an LED or an LED unit made up of several LEDs, for example an LED cluster or an LED module, but is not limited to this. The illuminant 3 is designed to emit light in the direction of the light guide 2 and the light distribution body 1 connected thereto.

The light guide 2 is formed by an elongate, essentially cylindrical body made of a transparent material, the longitudinal axis of which extends along a central axis of the lighting device. The central axis is shown in the exploded view of FIG. 1 as a dot-dash line. The light guide 2 has a light input surface 21 and a light output surface 22 at each axial end. The light coupling surface 21 and the light coupling surface 22 are preferably surfaces with a high degree of transmission, which can be achieved, for example, by appropriate polishing and/or application of a suitable coating. The outer surface of the light guide 2 can improve the light transmission between the light source 3 and the light distribution body 1 with a suitable MEISSNER BOLTE M/OCC-176-PC

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be provided with a reflective coating. Alternatively, the outer surface of the light guide 2 can be provided with an opaque cover. It is also possible that the lateral surface of the light guide 2 has no special modification and is formed by an untreated or not specially treated surface.

The light guide 2 is used to guide light emitted by the illuminant 3 into the light distribution body 1 . In order to couple the light into the light distribution body 1 , the body has a light coupling surface 11 . In the assembled state, the light guide 2 is attached to the light coupling surface 11 with the light coupling-out surface 22 . This can be seen in FIGS. 2 and 3, which show a schematic sectional illustration of the lighting device from FIG.

The illuminant 3 is attached to the light coupling surface 21 of the light guide. The light output surface 22 of the light guide 2 is attached to the light input surface 11 of the light distribution body 1 . Light emitted by the illuminant 3 is thus coupled into the light guide 2 via the light coupling surface 21 . The light is then conducted in the light guide 2 to the light coupling surface 11 of the light distribution body 1 . Finally, the light is coupled into the light distribution body 1 from the light coupling-out surface 22 of the light guide 2 via the light coupling-in surface 11 of the light distribution body 1 .

The light distribution body 1 in the embodiment shown in Figs. 1 to 3 has a convex shape. Specifically, the light distribution body 1 shown there is essentially spherical. The shape of the light distribution body 1 deviates from a spherical shape only at the light coupling surface 11 . The light coupling surface 11 in the embodiment shown in FIGS. 1 to 3 is—corresponding to the light coupling surface 22 of the light guide 2—planar. This can be achieved, for example, by grinding down the light distribution body 1 at the location of the light coupling surface 11 . In other exemplary embodiments that are not shown, the light coupling surface 11 of the essentially spherical light distribution body 1 is obtained by polishing a region of the spherical surface and is convex. In this case, the light coupling-out surface 22 of the light guide 2 is concave with a size and curvature corresponding to the size and curvature of the light coupling-in surface 11 of the light distribution body 1 . MEISSNER BOLTE M/OCC-176-PC

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The light distribution body 1 is solid and is formed of a transparent material such as glass or transparent plastic. Glass is preferred as the material for the light distribution body 1 . In order to emit the coupled-in light, the light distribution body 1 has a light exit area 12 on its surface. In the case of the essentially spherical light distribution body 1 shown in FIGS.

The light exit area 12 of the light distribution body shown in Fig. 1 to 3 is formed by a matted or satined surface, i.e. a finely roughened surface, on which light inside the light distribution body 1 is diffusely scattered and through which light from the inside of the light distribution body 1 diffuses exit. Such a surface can be obtained in the case of a light distribution body 1 made of glass, for example by sandblasting or etching.

With the lighting device according to the exemplary embodiment shown in FIGS. 1 to 3, a radiation characteristic can be produced which contains both a directional component and a diffuse component. This is explained below with reference to FIGS. 4 to 6. FIG.

FIG. 4 is a schematic illustration of the emission characteristics that can be achieved with the lighting device according to FIGS. 1 to 3. FIG. 5 shows a variation of the exemplary embodiment shown in FIGS. 1 to 3 without a light guide 2, with which a radiation characteristic with a directed and diffuse component can also be obtained.

First, the radiation characteristics of the lighting device with the configuration according to FIG. 4 are explained. Light that is emitted by the illuminant 3 is guided into the light distribution body 1 via the light guide 2 . Exemplary beam paths through the light guide 2 are shown schematically by the arrows in the light guide 2 . The illuminant 3 does not emit collimated light, but emits light over a certain angular range. This can also lead to reflections on the inner wall of the light guide 2 . MEISSNER BOLTE M/OCC-176-PC

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Light that is coupled into the light distribution body 1 from the light guide 2 therefore enters the light distribution body 1 at different angles.

Since the light distribution body 1 is solidly formed from a transparent material, a first part of the coupled light, which enters the light distribution body 1 at a sufficiently small angle with respect to the central axis of the lighting device shown in broken lines, is partially collimated or directed. This (first) part of the light that is coupled in emerges in a directed manner from the light distribution body 1 in a region of the light exit region 12 which is opposite the light coupling surface 11 . This is shown in FIG. 4 by the solid arrows at the upper end of the light distribution body 1, which represent the directed portion of the emitted light.

A second part of the coupled-in light--essentially the light that does not emerge in a directed manner in the area of the light exit area 12 that is opposite the light entry surface 11--exits diffusely from the light distribution body over the entire light exit area 12. As conceptually illustrated in FIG. As a result, the second part of the coupled-in light is distributed uniformly over the light distribution body 1 and exits essentially diffusely over the entire light exit region 12 of the light distribution body 1 . This is shown in FIG. 4 by the dotted arrows on the surface of the light distribution body 1, which represent the diffuse portion of the emitted light. Due to the frosted surface, additional scattering takes place when the light exits the light exit area 12 .

In the exemplary embodiment shown in FIG. 5, no light guide 2 is present. Here, the light emitted by the illuminant 3 is coupled directly into the light distribution body 1 via the light coupling surface 11 . However, directed and diffuse light is generated essentially analogously to the exemplary embodiment shown in FIG. 4 and described above. Again, a (first) part of the coupled light is directed by the collimating effect of the massive light distribution body 1 and occurs over part of the light exit area 12, which is the MEISSNER BOLTE M/OCC-176-PC

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Opposite light coupling surface 11 directed from. A (second) part of the coupled-in light (essentially the part that does not exit the light distribution body 1 in a directed manner) is distributed over the light distribution body 1 by internal reflections on the frosted surface and essentially passes through the frosted surface over the entire light exit area 12 diffuse off.

The emission characteristic, which can be achieved with the lighting device according to the present invention and in particular with the lighting devices shown in FIGS. 4 and 5, is formed from the superimposition of a diffuse and a directional component. This is shown schematically in the graph in FIG. The polar angle Q of a spherical coordinate system with its origin in the center of the light distribution body 1 is shown on the x-axis. A value of 0° designates the direction along the central axis of the lighting device away from the light coupling surface 11 . The intensity of the light emitted at the respective angle Q is given on the y-axis without a specific unit.

The (first) portion of the emitted light, which forms the directed portion, exits via a region of the light exit region 12 that is opposite the light coupling surface 11 . This directed light exit is shown in Fig. 6 as an increased emission intensity at small values of Q. The (second) portion of the emitted light, which forms the diffuse portion, is diffusely emitted essentially over the entire light exit area 12 and manifests itself as constant Background in the graph in Fig. 6.

Overall, the lighting device according to the invention therefore produces an emission characteristic with a directional component for the targeted illumination of a limited spatial area and a diffuse component for the uniform illumination of a large spatial area. In other words: the lighting device according to the invention is suitable for generating spot lighting with a very soft spot that transitions into a diffuse lighting component that is emitted over almost the full solid angle. Surprisingly, the intensity of the diffuse component is so high here that the diffuse component enables atmospheric, uniform illumination. At the same time, the intensity of the directed part is so high that the directed MEISSNER BOLTE M/OCC-176-PC

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produces a significantly brighter, soft spot that can be used to specifically illuminate a limited area of the room.

The lighting device according to the invention emits both directed and diffuse light from the light distribution body 1, with only a single light source 3 being required for this. In addition, only one compact optical element is required to generate the radiation characteristics with a directional and a diffuse component. From the coupled-in light, the light distribution body 1 generates both a directed component of emitted light over a limited solid angle range and a diffuse component of emitted light, which is emitted over a very large solid angle range.

The emission characteristics described with reference to FIGS. 4 to 6 can be suitably changed by simple modifications of the light distribution body 1, depending on the lighting requirement. If, for example, it is desired that no light is emitted over a certain solid angle range, corresponding areas of the surface of the light distribution body 1 can be excluded from the light exit area 12 by applying a cover or a reflective coating with total reflection. The use of a reflective coating is preferred here, since the light yield can be improved in this way. Light that is reflected in the interior of the light distribution body 1 on the reflective coating can continue to exit the light distribution body 1 via the light exit area 12 .

7 and 8 show two schematic views of a lighting device with a correspondingly modified light distribution body 1. The light distribution bodies 1 in FIGS. 7 and 8 are provided with a reflective coating 13 in certain areas. No light emerges from the light distribution body 1 in the area of the reflective coating 13 , so that the areas with the reflective coating 13 do not form part of the light exit area 12 .

In the configuration shown in FIG. 7, a region of the surface of the light distribution body opposite the light coupling surface 11 is provided with a reflective coating 13. With this configuration, the share of MEISSNER BOLTE M/OCC-176-PC

16 directed light strongly suppressed. The remaining light exit area 12 emits essentially diffuse light, which was partially reflected on the reflection coating 13 inside the light distribution body.

In the configuration shown in FIG. 8 , a reflective coating 13 is applied over an annular area of the surface of the light distribution body 1 . With this configuration, a superimposition of directed and diffuse light is emitted in a region of the light exit region 12 which is opposite the light coupling surface 11 . Another part of the light exit area 12 is adjacent to the light coupling surface 11 and is used to emit diffuse light. A region in which no light is emitted is formed with the reflection coating 13 between the two parts of the light exit region 12 .

Instead of a reflective coating 13, a tinting in certain areas on the surface of the light distribution body 1 or a coating with a reduced transmittance can also be provided, so that the intensity of the emitted light can be reduced and adjusted in these areas.

The exemplary embodiments with modified emission characteristics shown in FIGS. 7 and 8 can also be combined with the configuration of the lighting device without light guide 2 shown in FIG.

The proportion of the light coupled into the light distribution body 1 which is emitted in a directed manner is emitted over a surface region which is opposite the light coupling surface 11 when using a substantially spherical light distribution body 1 . In order to be able to set the direction of the directed light component, the lighting device can be movably mounted. It is particularly preferred here to mount the lighting device in such a way that the light distribution body 1 is mounted such that it can rotate about its center. With such a bearing, the direction of the directed emitted light can be changed by rotating the light distribution body 1 without the light distribution body 1 changing its absolute position.

This is illustrated in Figs. 9 and 10. According to this exemplary embodiment, the lighting device is mounted in a holder 4 shown schematically in such a way that the light distribution body 1 can be rotated about its center. in the in MEISSNER BOLTE M/OCC-176-PC

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In the position shown in FIG. 9, the directed portion of light that is emitted by the lighting device is radiated vertically upwards. If the light distribution body 1 is rotated in the holder, the direction of the light emitted in a directed manner changes, as shown in FIG. 10 . However, the position of the light distribution body 1 remains unchanged. As a result, a lighting device can be created that requires little space and has an emission characteristic with a diffuse portion and a directed portion, with the emission direction of the directed portion being adjustable.

The configuration with holder shown in Fig. 9 and Fig. 10 can be combined both with the configuration shown in Fig. 5 without light guide 2 and with a light distribution body 1 with modified emission characteristics according to the reference to Fig. 7 and Fig. 8 described embodiments.

In order to protect the light distribution body 1 and in particular its frosted surface from contamination and damage, the lighting device can have a (transparent) dome that at least partially encloses the light distribution body 1 . Such a configuration is shown in FIG. In addition to the light distribution body 1 , the light guide 2 and the illuminant 3 , the lighting device has a dome 5 which surrounds the light distribution body 1 . In order to improve the overall aesthetic impression, it is preferred in this exemplary embodiment if the lateral surface of the light guide 2 is provided with an opaque cover or coating (not shown). As a result, the visibility of the light guide 2 is reduced so that the optical impression is created that the light distribution body 1 is floating inside the dome 5 .

In order to modify the emission characteristics of the lighting device according to FIG. 11, the dome 5 can be provided with coatings with a reduced degree of transmission in some areas. This is shown schematically in FIG. The dome 5 has a first (partially) reflective coating 51 in an upper area and a second (partially) reflective coating 52 in an annular area around the upper area. The degrees of transmission of the coatings 51, 52 differ from one another. Coatings with a transmittance of 0 can be used, i.e. fully reflective coatings, or partially reflective MEISSNER BOLTE M/OCC-176-PC

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Coatings with a transmittance between 0 and 1. A tinting of the dome 5 in certain areas can also be used in order to modify the emission characteristics of the lighting device.

If, in the exemplary embodiment shown in FIG. A portion emitted diffusely by the light distribution body 1 emerges through the region of the second coating 52 , the intensity of which is reduced by the second coating 52 . This creates a glare-free lighting device with a diffuse emission characteristic over a limited spatial area.

The configuration of the coatings 51, 52 shown in FIG. 12 is purely exemplary. It is obvious to the person skilled in the art that any combination and arrangement of coatings and/or tinted areas on the dome 5 can be used to achieve a desired modification of the emission characteristics of the lighting device. The dome 5 can also be configured to be removable and interchangeable. As a result, the radiation characteristics of the lighting device can be modified by simply replacing the dome 5 with a dome with a different configuration of the coatings and/or tinting, without requiring a modification or change to the light distribution body 1 or the light source 3 .

It is obvious to a person skilled in the art that the exemplary embodiments shown in FIGS. 11 and 12 with the dome 5 can be combined with the other exemplary embodiments described.

reference list:

1 light distribution body

11 light coupling surface

12 light emission area

13 reflective coating

2 light guides MEISSNER BOLTE M/OCC-176-PC

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21 (second) light coupling surface

22 light decoupling surface

3 bulbs

4 bracket

5 dome

51 first (partly) reflective coating

52 second (partly) reflective coating

Claims

MEISSNER BOLTE M/OCC-176-PC20 claims 1. Lighting device, in particular for illuminating an interior, comprising: - A light source (3); - A light distribution body (1) with a light coupling surface (11) and a translucent light exit area (12); wherein the light distribution body (1) is designed to emit a first part of the light emitted by the illuminant (3) and introduced into the light distribution body (1) via the light coupling surface (11) in a directed manner, and a second part of the light introduced by means of the light distribution body ( 1) to scatter, so that the light exits diffusely essentially over the entire light exit area (12) of the light distribution body (1). 2. Lighting device according to claim 1, having a light guide (2) which is designed to direct light emitted by the lighting means (3) to the light coupling surface (11) of the light distribution body (1). 3. Lighting device according to claim 1 or 2, wherein the light distribution body (1) is formed by a substantially spherical body made of a transparent material, preferably glass or a transparent plastic. 4. Lighting device according to one of the preceding claims, wherein the light exit area (12) of the light distribution body (1) is formed by a frosted surface. 5. Lighting device according to one of the preceding claims, wherein the light coupling surface (11) is formed by a smoothly ground or polished area on the surface of the light distribution body (1). MEISSNER BOLTE M/OCC-176-PC 21 6. Lighting device according to one of the preceding claims, wherein the lighting means (3) is formed by one or more LEDs and is preferably designed as an LED cluster or LED RGB module. 7. Lighting device according to one of the preceding claims, wherein the light distribution body (1) has on its surface areas with a reflection coating (13) which is designed to light that propagates inside the light distribution body (1) and on the reflection coating (13) meets to reflect partially or fully. 8. Lighting device according to one of the preceding claims, comprising a holder (4) in which the light distribution body (1) is rotatably mounted about its center. 9. Lighting device according to one of the preceding claims, comprising a dome (5) which encloses the light distribution body (1). 10. Lighting device according to claim 9, wherein the dome (5) has surface areas (51, 52) with different transmittance, which preferably have partially reflective coatings and are designed to modify the emission characteristics of the light distribution body (1).