LIGHTING DEVICE

Abstract

Operating device comprising a lighting device (1; 21) for illuminating the interior of a vehicle and at least one sensor, wherein the lighting device (1; 21) comprises: - a first, plate-shaped light guide (2) with a light output surface (3) formed on a first flat side and serving as an operating surface, - at least one first light source (4) for coupling light into at least one edge (5) of the first light guide (2), - at least one second light guide (6; 6a, 6b) with a light input surface (7) and a light output surface (8), and - at least one light source (10; 4) for coupling light into the light input surface (7) of the at least one second light guide (6; 6a, 6b), wherein - the light output surface (8) of the at least one second light guide (6;6a, 6b) is configured for coupling the light coupled out there into a second flat side (9) of the first light guide (2) and- the at least one light source (10) for coupling light into the light coupling surface (7) of the at least one second light guide (6; 6a, 6b) is at least a second light source (10) different from the at least one first light source (4) and- the lighting device (1; 21) is configured to change a light emission pattern that can be coupled out at the light coupling surface (3) of the first light guide (2) depending on sensor data of the at least one sensor.;

Description

Technical FieldThe present invention relates to a lighting device, which has a first, plate-shaped light guide with a light decoupling surface formed on a first flat side and at least one first light source for light coupling into at least one edge of the first light guide. The lighting device is particularly advantageous for use as a vehicle lighting device, in particular for illuminating an interior of a vehicle.Prior ArtDE 10 2014 003 527 A1 discloses an aircraft lighting device for the cabin of an aircraft, which includes an LED lighting device for outputting an illumination light and a light distribution body, wherein the LED lighting device is arranged in or on the light distribution body, so that the illumination light is coupled into the light distribution body and coupled out in a two-dimensionally distributed manner, wherein the light distribution body consists of a transparent, flexible plastic.US 2015 / 0251594 A1 discloses an interior lighting device for fastening to a ceiling section of a cabin interior of a passenger aircraft. The transparent surface illumination source and the reading lamps are highly integrated and the reading lamp is located behind the transparent light source. The interior lighting device comprises: a transparent surface lighting source for providing diffused light to the cabin, the transparent surface lighting source comprising an at least partially transparent plate-shaped illuminatable body, the body having a front side and a rear side, and the front side being configured to be aligned with the cabin; and at least one reading light is provided at the rear side of the illuminatable body to direct a focused spot of light through the illuminatable body.DE 102010000038 A1 relates to a lighting device for vehicles with a plurality of light guiding elements crossing one another, wherein one light guiding element has a receiving contour for receiving another light guiding element.DE 102016114744 A1 relates to an illuminated badge for vehicles having a plurality of light sources and light guides for the targeted illumination of characters and background regions.EP 2354637 A2 relates to a vehicle lighting device having two flat light guide elements which generate different light functions and are connected to one another.DE 102015200006 A1 relates to a device for assisting a user before the operation of a switch for electromotively adjusting a vehicle part by detecting an approach and displaying an indication.DE 102007018892 A1 relates to a reflection-optical operating device for vehicles with a flat sensor surface and light guides for guiding light and display devices for feedback.DE 102005038161 A1 relates to an input device with a touchscreen and actuator for generating haptic feedback as a function of the movement speed via the operating surface.DE 10 2009 005 351 A1 relates to a vehicle light having a plurality of superimposed light guides and light deflectors arranged offset, which couple out the light of an LED light source in a second direction.DE 10 2008 048 764 A1 relates to a lighting device for motor vehicles having a planar light guide element which consists of a plurality of light guide segments which converge in an intersecting region and serve for generating different light functions.JP 2017147105 A relates to a vehicle lamp having a light guide made up of a light guide rod and a light guide plate, both elements receiving light from light sources and radiating it in different directions.DESCRIPTION OF THE INVENTIONIt is an object of the invention to overcome the disadvantages of the prior art at least partially and in particular to provide a structurally particularly compact and robust possibility for multiple-design illumination.The object is achieved by the subject matters of the independent claims. Advantageous developments of the invention are specified in the dependent claims, the description and the accompanying figures.The object is achieved by a lighting device, comprising a first, plate-shaped light guide having a light decoupling surface formed on a first flat side, at least one first light source for light coupling into at least one edge of the first light guide, at least one second light guide having a light coupling surface and a light decoupling surface, and at least one light source for light coupling into the light coupling surface of the at least one second light guide, wherein the light decoupling surface of the at least one second light guide is configured for light coupling of the light decoupled there into the second flat side of the first light guide, and the at least one light source for light coupling into the light coupling surface of the at least one second light guide is at least one second light source different from the at least one first light source.This lighting device has the advantage that a largely homogeneous planar light emission through the light decoupling surface of the first light guide can be achieved by means of the at least one first light source. In addition, by means of the at least one light source for coupling light into the second light guide, local light effects within this light decoupling surface can be generated in a targeted manner using structurally simple means. Furthermore, a dynamic light emission pattern can advantageously also be implemented at this light decoupling surface. The at least one second light guide serves in particular for backlighting the first light guide, in particular with a pattern corresponding to the shape and / or arrangement of the at least one second light guide (e.g. a line pattern, grid pattern, etc.).The use of different first and second light sources advantageously enables a particularly multi-shaped light emission pattern to be generated, in particular with locally large color differences. In addition, the optical shape of the light emission pattern can be varied particularly greatly dynamically in this configuration.The plate-shaped light guide has a thickness which is significantly less than an extent in the surface direction of the light guide or perpendicular thereto. The plate-shaped light guide has in particular a thickness which is smaller by an order of magnitude than the surface area.The first light guide and the at least one second light guide consist of a material, which is transmissive to light-identical or different-for example plastic (PC, PMMA, etc.) or glass. The light guides are designed in particular to guide light by means of total internal reflection (so-called "TIR" light guides).The fact that the at least one first light source is provided for coupling light into at least one narrow side or edge of the first light guide can mean, in particular, that it is designed and arranged such that the light coupled out or couplable out from it is coupled or couplable into the first light guide at least partially, in particular predominantly, in particular practically completely, through the edge. The edge therefore corresponds to the light coupling surface for the light of the at least one first light source.Light emitted by the light decoupling surface of the first light guide can be referred to in particular as "useful light", which is provided to implement the lighting function of the lighting device.In one refinement, which is advantageous for particularly homogeneous and loss-free light output from the light decoupling surface of the first light guide, at least one of the flat sides of the first light guide has a light decoupling structure, for example in the form of an array of microlenses.Because the light decoupling surface of the at least one second light guide is configured for coupling the light decoupled there into the second flat side of the first light guide, the light of the at least one light source radiating therein does not radiate directly onto the second flat side of the first light guide, but is initially guided through the at least one second light guide. The at least one second light guide advantageously enables a structurally robust, compactly implementable and low-loss beam shaping. The light coupled into the second flat side of the first light guide runs through the first light guide to its first flat side and is coupled out there. This makes it possible to emit the light of the at least one light source assigned to the second light guide, emitted on the light decoupling side of the first light guide, in virtually the same form as on the light decoupling side of the at least one second light guide, optionally with a small widening.In one development, the at least one second light guide is arranged such that the light decoupled from it falls substantially perpendicularly onto the second flat side. This achieves the advantage that virtually no reflection losses occur during the coupling into the first light guide and also not during the subsequent decoupling from the first flat side of the first light guide.In one development, at least one light source has at least one light emitting diode (LED). The at least one LED can emit monochromatic light or color-tunable light. For example, the at least one first light source can have at least one LED.In one development, the at least one first light source and / or the at least one second light source comprises a plurality of light sources. This enables a particularly varied generation of light, in particular also in a plurality of different colors. In particular, the at least one first light source and the at least one second light source can be controlled independently of one another.In an additional or alternative development, the at least one first light source and / or the at least one second light source each comprise exactly one light source, in particular a planar light source. One possible example of a planar light source can be an OLED, for example in the present case as a strip-shaped OLED.In one configuration, the at least one second light guide is configured in one piece or in one piece with the first light guide and the light decoupling surface of the at least one second light guide merges without an air gap into the second flat side of the first light guide. This results in the advantage of a particularly robust and compact light guide. It is also possible in this way to virtually completely avoid light losses during the transition from the at least one second light guide to the first light guide. In the case of a one-piece embodiment, the light guides can have been produced in one piece, for example as an injection molded body.In another configuration, the at least one second light guide is arranged separately from the first light guide. This enables a particularly flexible construction of the light guides with respect to one another.In another configuration, the light decoupling surface of the at least one second light guide is smaller than the light decoupling surface of the first light guide. Thus, the generation of localized light regions at the light coupling surface of the first light guide is particularly simplified.In another configuration, the at least one second light guide is a flat light guide, the light coupling surface of which corresponds to a first edge or narrow side of the at least one second light guide and the light coupling surface of which corresponds to a second edge or narrow side of the second light guide. This advantageously enables a particularly easily implementable and low-loss possibility for generating sharp, localized light regions on the light coupling-in surface of the first light guide. The second edge is in particular the edge opposite the first edge. The two edges can run parallel to one another.In another configuration, the at least one second light guide is a flat light guide, the light coupling surface of which corresponds to at least one edge of the second light guide and the light decoupling surface of which corresponds to a flat side of the second light guide. Thus, a particularly easily implementable possibility for generating even relatively large localized light regions on the light coupling-in surface of the first light guide is advantageously provided.In another configuration, the at least one second light guide is an elongate, in particular band-shaped, light guide. This results in the advantage of particularly simple production. The at least one second light guide can be straight or curved in the longitudinal extension. By means of such an elongate second light guide, a local band- or strip-shaped useful light component can be superimposed on the two-dimensionally homogeneous useful light component at the light decoupling surface of the first light guide, which is generated by means of the at least one first light source.The ribbon-shaped light guide can have in particular the same height along its longitudinal extension.In one refinement, the ribbon-shaped light guide is rectilinear in its transverse direction (i.e. perpendicular to its longitudinal extent and its depth direction). In another development, the band-shaped light guide is curved in its transverse direction (i.e. perpendicular to its longitudinal extension and its depth direction), which enables a particularly flat construction.In one refinement, an LED light strip is arranged on the edge-like light coupling surface of the first light guide and / or of the at least one second light guide, which follows the course of the edge. This significantly facilitates an arrangement of the LEDs. An LED light strip can be understood in particular as an elongate substrate on which a plurality of LEDs, in particular LED chips, are arranged in series. The LEDs can be arranged in particular equidistantly. The LEDs can be controlled jointly or individually. In particular, individually controllable LEDs can be individually controllable with respect to their brightness and / or their light color. The substrate may be a rigid or flexible printed circuit board ("flex band"). The light strip can also be referred to as a "light source strip" or-if LEDs are present-as an "LED chain".In another configuration, the at least one second light guide has a plurality of second light guides running parallel to one another.In another configuration, the at least one second light guide has a plurality of light guides running crossing one another.In another configuration, a plurality of second light guides are connected to one another as light guide sections in one piece to form a single second light guide. Thus, its / its arrangement on the first light guide can be achieved particularly easily and with small tolerances. In other words, the at least one second light guide is then exactly one light guide which has a plurality of light guide sections running intersecting one another. The intersecting areas can be notionally assigned to each light guide section running intersecting there.In another embodiment, the second light guide has a lattice-compartment-like basic shape. The basic shape in the form of a lattice compartment corresponds in particular to a shape in which a first group of second light guides or light guide sections running parallel to one another and equidistant from one another crosses a second group of second light guides or light guide sections running parallel to one another and equidistant from one another, in particular at right angles. In this embodiment, a light decoupling surface is produced in the form of a grating or cross grid. In particular, the light guides or light guide sections can be oriented "standing up", wherein adjacent light guides or light guide sections are opposite each other with their flat sides.In another embodiment, the first light guide is made of transparent material and the at least one second light guide is made of opaque material, in particular of plastic such as (PC, PMMA, etc.). The opaque or translucent material (which can be "milky white", for example) achieves the advantage that a particularly high light homogeneity can be achieved at the decoupling surface of the second light guide even with second light guides of low height (and thus an only short travel path of the light within the second light guides). Due to the transparent configuration of the first light guide, however, a high local sharpness of this light at the light decoupling surface of the first light guide is maintained. It is a development which is particularly advantageous for this configuration in the case of a one-piece construction if the first light guide and the at least one second light guide are produced as a single two-component injection-molded body.In principle, the at least one second light guide can also consist of transparent material and / or the first light guide can consist of opaque material.In another configuration, the lighting device has at least one sensor and is configured to change a light emission pattern that can be decoupled at the light decoupling surface of the first light guide as a function of sensor data of the at least one sensor. As a result, the lighting device can advantageously also be used as an operating device for interactive control. The light decoupling surface can then serve as an operating surface. According to a development, one or more vehicle functions can be controlled by means of the at least one sensor. Feedback can be implemented via light effects of the lighting device. This results in the advantage, for example, that the number of switches in the vehicle can be reduced, which in turn brings about a cleared, particularly high-quality impression of the interior.In another configuration, the at least one sensor comprises at least one touch-sensitive sensor. This results in the advantage that the light decoupling surface can be used as a touch-sensitive operating surface. The touch-sensitive user interface can, for example, detect touches in a spatially resolved manner and / or be configured for gesture control. The at least one sensor can be a capacitive, resistive or inductive sensor, for example.Alternatively, the sensor may be, for example, an infrared sensor, a camera, an ultrasonic sensor, etc.In another configuration, the lighting device is a vehicle lighting device. In one development, the vehicle lighting device is a lighting device for vehicle interior lighting (interior lighting). This results in the advantage that vehicle occupants can be presented with particularly multiple possibilities for interior lighting. In a development, the vehicle occupants can thereby select the light emission pattern emitted by the vehicle lighting device themselves. Alternatively or additionally, information can be transmitted to the vehicle occupant by means of the light emission pattern in a variety of ways, for example in the form of numbers and / or letters.The vehicle may be a motor vehicle (e.g. a motor vehicle such as a passenger car, lorry, bus etc. or a motorcycle), a railway, a watercraft (e.g. a boat or a ship) or an aircraft (e.g. an aircraft or a helicopter).Brief description of the FiguresIn the following, an advantageous embodiment of the invention is explained with reference to the accompanying figures. The following are shown: FIG. 1 shows a lighting device according to a first exemplary embodiment in a view obliquely from behind; FIG. 2 shows the lighting device according to the first exemplary embodiment in a view from the front with an indicated first light emission pattern; FIG. 3 shows a view obliquely from the rear of a lighting device according to a second exemplary embodiment; FIG. 4 shows the lighting device according to the second exemplary embodiment in a view from the front with a second indicated light emission pattern; and FIG. 5 shows the lighting device according to the second exemplary embodiment in a view from the front with a third indicated light emission pattern.FIG. 1 shows, in a view obliquely from the rear, a lighting device 1 having a first, plate-shaped light guide 2 with a light decoupling surface 3 formed on a first flat side (front side) and having a plurality of light sources in the form of individual LEDs 4 for coupling light, two opposite edges 5 of the first light guide 2.The first light guide 2 is, for example, not quite planar, but rather slightly curved in a plane direction. However, the first light guide 2 can also be a planar light guide. Its thickness is in particular constant.The lighting device 1 also has a plurality of (here: three) strip-shaped second light guides 6 each having a light input surface 7 and a light output surface 8. The second light guides 6 have a strip-shaped basic shape and are oriented perpendicular to a second flat side (rear side) 9 of the first light guide 2. The light coupling surface 7 and the light decoupling surface 8 correspond to opposite, parallel longitudinal edges of the second light guides 6.The light decoupling surfaces 8 slightly widened and concavely shaped in the thickness direction are directed frontally onto the rear side 9 of the first light guide 2. The second light guides 6 can therefore also be referred to or considered as vertically arranged webs. This alignment allows a particularly low-loss light coupling of the light coupled out of the second light guides 6 into the rear side 9 of the first light guide 2.The second light guides 6 are oriented parallel and equidistant to one another, but can generally also be arranged differently. They can be oriented upright, i.e. adjacent second light guides 6 are opposite each other with their flat sides.The second light guides 6 can be spaced apart from the rear side 9 of the first light guide 2 or border the rear side 9 without an air gap. In a variant, the first light guide 2 and the second light guides 6 have been produced separately. In another variant, the first light guide 2 and the second light guides 6 have been produced together in one piece or in one piece, for example as an injection-molded part. A simple and cost-effective production is supported in that the first light guide 2 and the second light guides 6 consist of plastic, e.g. of PC, PMMA, etc. In particular, the second light guides 6 can consist of opaque plastic, while the first light guide 2 consists of transparent plastic. In this case, the light guides 2 can be manufactured integrally by two-component injection molding.On the respective light coupling surfaces 7, an LED light strip 11 with a plurality of second light sources in the form of LED chips 10 arranged in series is attached in each case, which follows the shape of the edge-shaped light coupling surfaces 7. The light emitted by the LED chips 10 is coupled into the associated light coupling surface 7.The LED chips 10 and the LEDs 4 can be controlled independently of one another, for example by means of a control unit, not shown. In particular, the LED light strips 11 can also be controlled independently of one another. In particular, the LED chips 10 of an LED light strip 11 can also be controlled independently of one another. The LED chips 10 and / or the LEDs 4 may be dimmable. The LED chips 10 and / or the LEDs 4 can be variable in color. The LED chips 10 and the LEDs 4 can emit light of different light colors, in particular.The light emitted by the LEDs 4 is coupled laterally into the first light guide 2 and coupled out highly uniformly from the light coupling-out surface 3. For this purpose, the light decoupling surface 3 can have a decoupling structure, be roughened, etc. This light generates a first portion L 1- 1 of a light emission pattern L 1, as indicated in FIG. 2 in a view of the light decoupling surface 3.The light emitted by the LED chips 10 is guided through the second light guides 6 and homogenized there. This light then passes through the first light guide 2 in the thickness direction and exits at the light extraction surface 3 as a second portion L 1- 2 of the light emission pattern L 1. The shape of the second portion L 1- 2 corresponds substantially to the shape after emission from the light decoupling surfaces 8, optionally with a small extension. The second portion L 1- 2 of the light emission pattern L 1 thus corresponds to a maximum of three strips, the position of which corresponds to the position of the light decoupling surfaces 8. If the LED chips 10 can be controlled band-wise or individually, the second portion L 1- 2 can be varied accordingly with respect to brightness and / or color.If at least one sensor (see FIG. ) is assigned to the lighting device 1 and the lighting device 1 is configured to change a light emission pattern L 1 that can be decoupled from the light decoupling surface 3 or the portions L 1- 1 and / or L 1- 2 thereof depending on sensor data of the at least one sensor, it can also be used as an operating device.In FIG. 2, an outer dashed border U also indicates an area visible by a user.The lighting device 1 can be in particular a vehicle lighting device, e.g. serving for interior lighting, as a display element, as a design element and / or as an operating element.FIG. 3 shows a lighting device 21 in a view obliquely from behind. The lighting device 21 has a similar basic structure as the lighting device 1.However, instead of the three parallel second light guides 6, 6 a, the lighting device 21 additionally has three strip-shaped second light guides 6, 6 bextending perpendicular thereto. The light guides 6 aand the light guides 6 bcross one another and thereby form a grid-compartment-like basic shape. The second light guides 6 a, 6 bare connected to one another in one piece to form a single light guide. The light guides 6 a, 6 bmay therefore also be regarded as light guide sections or as light guide regions of a single second light guide 6.Analogously to the light guides 6 a, 6 b, LED light strips 11 crossing one another in a grid-like manner are present.FIG. 4 shows the lighting device 21 in a view from the front with a second indicated light emission pattern L 2, in which, analogously to the lighting device 1, a first, two-dimensionally homogeneous portion L 2- 1 of the light emission pattern L 2 is generated by means of the light emission pattern L 2 generated by the first LEDs 4. A second portion L 2- 2 of the emission pattern L 2 is now, however, not linear in its maximum extent, but rather-analogously to the arrangement of the light guides 6 a, 6 b-grid-shaped.FIG. 5 shows the lighting device 21 in a view from the front with a third indicated light emission pattern L 3. The light emission pattern L 3 transmits information by means of the second portion L 3- 2, here: the letter "A". This can be implemented in that only that part of the LED chips 10 by means of which the "A" can be generated is connected. In particular, the turned-on LED chips 10 emit the same brightness and color.The figures are merely schematic representations and serve only to explain the invention. Identical or identically acting elements are provided with the same reference numerals throughout.LIST OF REFERENCE CHARACTERS1 Lighting device 2 First light guide 3 Light decoupling surface 4 LED 5 edge 6 Second light guide 6 aSecond light guide 6 bSecond light guide 7 Light coupling surface 8 Light decoupling surface 9 Rear side 10 LED chip 11 LED light strip 21 Lighting device L 1 First light emission pattern L 1- 1 First portion of the first light emission pattern L 1- 2 Second portion of the first light emission pattern L 2 Second light emission pattern L 2- 1 First portion of the second light emission pattern L 2- 2 Second portion of the second light emission pattern L 3 Third light emission pattern L 3- 1 First portion of the third light emission pattern L 3- 2 Second portion of the third light emission pattern U Border

Claims

Operating device, comprising a lighting device (1; 21) for illuminating an interior of a vehicle and at least one sensor, wherein the lighting device (1; 21) comprises: - a first, plate-shaped light guide (2) with a light decoupling surface (3) which is formed on a first flat side and serves as an operating surface, - at least one first light source (4) for coupling light into at least one edge (5) of the first light guide (2), - at least one second light guide (6; 6a, 6b) with a light coupling surface (7) and a light decoupling surface (8), and - at least one light source (10; 4) for coupling light into the light coupling surface (7) of the at least one second light guide (6; 6a, 6b), wherein - the light decoupling surface (8) of the at least one second light guide (6; 6a, 6b); 6 a, 6 b) for coupling the light coupled out there into a second flat side (9) of the first light guide (2), and - the at least one light source (10) for coupling light into the light coupling surface (7) of the at least one second light guide (6; 6 a, 6 b) is at least one second light source (10) different from the at least one first light source (4), and - the lighting device (1; 21) is configured to change a light emission pattern that can be coupled out at the light coupling-out surface (3) of the first light guide (2) as a function of sensor data of the at least one sensor.The operating device according to claim 1, wherein the at least one second light guide (6; 6a, 6b) is a flat light guide, the light coupling surface (7) of which corresponds to a first edge of the second light guide (6; 6a, 6b) and the light decoupling surface (8) of which corresponds to a second edge of the second light guide (6; 6a, 6b).Operating device according to one of the preceding claims, wherein the at least one second light guide (6; 6a, 6b) is a flat light guide, the light coupling surface (7) of which corresponds to at least one edge (5) of the at least one second light guide (6; 6a, 6b) and the light decoupling surface (8) of which corresponds to a flat side of the at least one second light guide (6; 6a, 6b) which faces the first light guide (2).Operating device according to one of the preceding claims, wherein the at least one second light guide (6; 6b, 6c) is a band-shaped light guide.Operating device according to one of the preceding claims, wherein the at least one second light guide (6; 6b, 6c) has a plurality of second light guides (6; 6a, 6b) running parallel to one another.Operating device according to one of the preceding claims, wherein the at least one second light guide (6b, 6c) has a plurality of light guides (6b, 6c) running crossing one another.Operating device according to one of the preceding claims, wherein the first light guide (2) consists of transparent material and the at least one second light guide (6; 6a, 6b) consists of opaque material.Operating device according to one of the preceding claims, wherein an LED light strip (11) is arranged in each case on the edge-like light coupling surface (7) of the first light guide (2) and / or of the at least one second light guide (6b, 6c), which follows the course of the edge (5), and wherein the light device (1; 21) has a plurality of light sources (10; 4) which can be controlled individually.Operating device according to one of the preceding claims, wherein one or more vehicle functions of the vehicle can be controlled by means of the at least one sensor.The operating device according to any one of the preceding claims, wherein the at least one sensor comprises at least one touch sensitive sensor.The operating device according to any one of the preceding claims, wherein the at least one sensor comprises an infrared sensor, a camera or an ultrasonic sensor.

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