Luminescent thin film with micro-optical structure

Abstract

The present invention relates to a light-emitting film (10) having a plurality of light-emitting diodes (12), a carrier layer (16), and a light-guiding layer (18) formed of a micro-optical structure that enables light radiated in multiple directions to be redirected along a common radiation direction (R) of the light-emitting film (10) so as to achieve uniform illumination of the surface (O) of the light-emitting film even when the light-emitting diodes are sparsely packed in the light-emitting film (10).

Description

Technical Field

[0001] The present invention relates to a multi-layer light-emitting film (Leuchtfolie) having a plurality of light-emitting diodes, a printed conductor layer, and a carrier layer well-known from the prior art, the printed conductor layer being used to electrically connect the light-emitting diodes. Background Art

[0002] Conventional light-emitting films are manufactured by stuffing a flexible carrier material with light-emitting diodes. Here, the uniform illumination of the film depends decisively on the number of light-emitting diodes located on the carrier material and the spacing between the light-emitting diodes. The degree of stuffing the carrier material with light-emitting diodes is the filling factor. If as high a uniformity as possible is to be achieved in the light radiation, this either results in as large a filling factor as possible, i.e., a very large number of light-emitting diodes and a very small spacing between the light-emitting diodes, or in an additional diffusely transmissive layer that scatters the light incident on the diffuser.

[0003] An increase in the number of light-emitting diodes increases the electrical power consumption of the light-emitting film and thus the thermal load, while an additionally installed diffusion layer leads to a significant increase in the film thickness and to a reduction in brightness. Therefore, the two solutions are usually applied in combination, however, this does not produce satisfactory results.

[0004] The two common solutions result in increased production costs and an increased power consumption of the film. In addition, another disadvantage of conventional light-emitting films with a large number of light-emitting diodes is the implementation of associated measures for cooling the light-emitting film, which in turn leads to a reduction in the plasticity of the film. Similarly, in combination with a thick diffusion layer that can be up to seven centimeters, the adverse effect of reduced film plasticity occurs more strongly, and this adverse effect can lead to the complete stiffening (Versteifung) of the film. Therefore, the diffusion layer is sometimes installed only after the light-emitting film has been positioned. Summary of the Invention

[0005] The object of the present invention is to provide a light-emitting film that can achieve good deformability of the light-emitting film with a low filling factor (i.e., a low density of light-emitting diodes and a small film thickness) and can achieve low-loss uniform illumination of the light-emitting film.

[0006] Description of the Invention

[0007] According to the present invention, this object is solved by a light-emitting film of the type mentioned at the beginning, characterized in that the film has a first micro-optical layer (Lage) for generating uniform illumination.

[0008] The micro-optical layer according to the invention has micro-optical structural elements, which have a lens structure, a prism structure, a polarizer structure, a filter structure, a phase-shifting film structure, a mirror (Spiegel) structure, a light-shielding plate structure, a lattice structure, fibers and / or light conductors for deflecting the light introduced into the micro-optical layer. The micro-optical structural elements obtain their micro-optical function by shaping and / or changing the refractive index of an optically homogeneous starting material, in particular an acrylic-based film.

[0009] The shaping can be carried out by means of typical methods such as melting, grinding, rolling, etching, extrusion and / or polishing. In terms of the methods mentioned, the listing should not be understood as being exhaustive.

[0010] In the case of using micro-optical structural elements, the micro-optical layer deflects the light introduced into the micro-optical layer through a defined optical path, in particular by arranging a plurality of micro-optical structures. Here, the optical path determines the exit point and the exit angle of the light beam according to the incidence point and the incidence angle. Here, the difference from a conventional diffuser lies in the inhomogeneous beam guidance through the optical layer, while the diffuser is characterized by a uniform beam path.

[0011] For this purpose, the micro-optical layer has a structured surface, which has repeating micro-optical regions. The micro-optical regions are used to turn the light introduced at different angles into the micro-optical layer. Preferably, the micro-optical regions are constructed mainly rotationally symmetrically, in particular circularly and / or elliptically, starting from an optical center located near the light-emitting diode, in particular exactly above the light-emitting diode. The micro-optical regions have a larger area than the light-emitting diode.

[0012] The size of the micro-optical regions is matched to the light-emitting diode pitch and can be different in the extension direction of the micro-optical layer. In particular, the micro-optical regions correspond to the light-emitting diode pitch in the extension direction of the micro-optical layer in terms of their direction-dependent dimensions. Thereby, it can be ensured that the light radiated by the light-emitting diode is reliably turned at least within half of the light-emitting diode pitch.

[0013] When adjacent micro-optical regions overlap, the light radiated by the light-emitting diode can be utilized particularly effectively. Thereby, the light can be utilized at a very large radiation angle.

[0014] The micro-optical layer can be composed of glass, fused quartz, polymers (in particular acrylic-based), and / or silicon. The use of crystals can also be considered. By using polymers, the cost for manufacturing the micro-optical layer can be particularly advantageously reduced.

[0015] Here, the term "light-emitting diode" is representatively used for all diodes, diode modules, diode components (dies, etc.) that emit light. Those skilled in the art know that the use of more specialized light-emitting diode components can lead to variations in the light-emitting thin film according to the present invention. Similarly, the term "light-emitting diode" should be understood to include all colors of light-emitting diodes and combined colors in light-emitting diode components.

[0016] Preferred embodiments and extensions

[0017] The following embodiment is preferred: In this embodiment, the light-emitting thin film has a textile layer or a non-woven layer on the film surface for light radiation. The textile layer or the non-woven layer can achieve particularly uniform illumination of the light-emitting thin film and, in addition, has acoustic advantages.

[0018] A preferred extension proposes that the textile layer or the non-woven layer is constructed by flocking the film. With flocking, the textile layer or the non-woven layer can be manufactured particularly simply and cost-effectively during the production of the film. It is also possible to consider applying the flocking at a later time point after the production of the film, for example, after assembling the film. Thereby, the textile layer or the non-woven layer can be particularly well protected from damage.

[0019] In a particularly preferred extension, the flocking consists of a mixture of various granules and / or fibers. Thereby, an irregular structure of the flocking can be particularly advantageously achieved, which is beneficial for particularly high sound absorption of the light-emitting thin film. Alternatively or additionally, the granular material can consist of light-transmitting, especially transparent, granules and / or fibers, whereby the illumination of the film can also be improved.

[0020] Instead of or in addition to the textile layer, non-woven fabric, and / or fabric, an upper layer can be provided, especially silicate gypsum, liquid wallpaper, antibacterial layer, and / or anti-adhesion layer.

[0021] Another preferred embodiment is as follows: In this embodiment, the first micro-optical layer mainly, especially completely, surrounds the light-emitting diode. Thereby, the light radiated by the light-emitting diode can be deflected particularly effectively by the micro-optical layer, light loss can be reduced, and the uniformity of the illumination of the thin film can be further improved.

[0022] The micro-optical layer is preferably constructed in the form of an embossed and / or pressed layer. Instead of or in addition to this, the micro-optical layer can be constructed integrally. The micro-optical structural element can be constructed in the form of a planar, integrated optical device of the micro-optical layer.

[0023] In a preferred embodiment, the light-emitting film has a mirror layer which is located behind the light-emitting diode in the radiation direction of the light-emitting film. This mirror layer reflects the light radiated against the light-emitting direction of the light-emitting film and ensures a more efficient and lower-loss utilization of the light radiated by the light-emitting diode.

[0024] In a particularly preferred embodiment, the mirror layer and the carrier layer form a common layer. This enables a particularly efficient and cost-effective production of the film because the mirror layer already exists during the production of the carrier layer. In addition, the mirror layer can thus be made particularly thin.

[0025] When using the mirror layer, the micro-optical layer can be particularly effectively arranged behind the light-emitting diode and in front of the mirror layer in the radiation direction of the light-emitting film. Thereby, the optical path can be extended by the micro-optical layer or the micro-optical layer can be made particularly thin. In this case, the light radiated by the light-emitting diode against the radiation direction of the light-emitting film is first deflected by the micro-optical layer against the radiation direction of the light-emitting film until it reaches the mirror layer. The mirror layer reflects the incident light in the radiation direction of the light-emitting film. Thereby, the light is deflected again by the micro-optical layer so that it finally exits on the surface of the light-emitting film. Thereby, the efficiency of the light deflection by the micro-optical layer and the proportion of the light utilized are further increased.

[0026] The following embodiment is preferred: In this embodiment, the light-emitting film has an additional micro-optical layer which has micro-optical structural elements, wherein the light-emitting diode is arranged between the two micro-optical layers. Thereby, an effective light deflection can be particularly advantageously achieved and the production overhead can be reduced based on the layer arrangement.

[0027] The following embodiment is particularly preferred: In this embodiment, the carrier layer is made of a film, a nonwoven fabric and / or a fabric, in particular a textile, and particularly preferably paper. This offers the advantage of a wide range of applications because the carrier layer can be adapted to the prevailing conditions of the place of use. In a special expansion, the carrier layer can be made translucent, in particular completely transparent. Thereby, the light-emitting effect of the film can be implemented on both sides.

[0028] In addition, the following embodiment is preferred: In this embodiment, the printed conductor layer is made partially translucent, in particular completely translucent. The translucency of the printed conductor layer enables the printed conductor layer to be arranged in front of the light-emitting diode in the radiation direction of the light-emitting film without the conductor layer disturbing the light-emitting effect of the film.

[0029] In a preferred embodiment, the printed conductor layer can be made of copper, conductive ink, indium zinc oxide and / or silver oxide.

[0030] Also preferred is the following embodiment: In this embodiment, the textile layer or non-woven layer is oriented in a unidirectionally light-transmissive manner, in particular along the radiation direction of the light-emitting film. Thereby, the light-emitting effect of the film can be implemented particularly uniformly.

[0031] Particularly preferred is the following embodiment: In this embodiment, the textile layer or non-woven layer is at least partially acoustically hard (schallhart) and / or acoustically soft (schallweich). This enables the use of the light-emitting film in fields with acoustic pre-given conditions or the use of the light-emitting film to improve acoustic conditions. Therefore, depending on the pre-given conditions, the textile layer can be constructed to be sound-absorbing and / or sound-reflecting.

[0032] In one embodiment, it is proposed that the spacing of the light-emitting diodes is between 1 mm and 200 mm, in particular between 4 mm and 150 mm, and particularly preferably between 8 mm and 100 mm.

[0033] In a special embodiment, the filling factor of the light-emitting film is between 5% and 50% in the case of uniform illumination, in particular between 7% and 25%, and particularly preferably between 9% and 15%.

[0034] Preferred is the following embodiment: In this embodiment, the film thickness is between 0.1 mm and 40 mm, in particular between 0.2 mm and 30 mm, and particularly preferably between 0.3 mm and 20 mm. Here, the film thickness refers to the main film thickness without considering the optional textile layer.

[0035] Particularly preferred is the following embodiment: In this embodiment, the light-emitting film is configured to be bendable, in particular rollable (rollbar). In particular, the bending radius and / or the winding radius are between 1 cm and 10 cm, and particularly preferably between 2 cm and 5 cm.

[0036] Also preferred is the following embodiment: In this embodiment, the control device of the light-emitting diodes is arranged on the film, in particular in the film, and particularly preferably directly on the light-emitting diodes of the film. The control device arranged in this way simplifies the installation and supply of the light-emitting film and reduces the space required for installing the light-emitting film.

[0037] Other advantages of the present invention can be derived from the description and the drawings. Similarly, according to the present invention, the features mentioned above and further explained can be applied alone or in any combination of multiple ones. The embodiments shown and described should not be understood as an exhaustive list, but have exemplary features for the explanation of the present invention. Description of the Drawings

[0038] Figure 1Schematic diagram showing a first embodiment of a light-emitting thin film according to the present invention;

[0039] Figure 2 Schematic diagram showing a second embodiment of a light-emitting thin film according to the present invention;

[0040] Figure 3 Schematic diagram showing a third embodiment of a light-emitting thin film according to the present invention. Detailed implementation mode

[0041] Figure 1 Schematic diagram showing a first embodiment of a light-emitting thin film 10 according to the present invention, which has a plurality of light-emitting diodes 12 (for the sake of clarity, only one light-emitting diode is provided with a reference numeral), a printed wire layer 14, a carrier layer 16, and a micro-optical layer 18, and the printed wire layer electrically connects the light-emitting diodes 12.

[0042] To vividly show the effect caused by the micro-optical layer 18, this schematic diagram shows the light-emitting effects of the light-emitting diodes with and without the micro-optical layer 18. The two light-emitting diodes 12 arranged on the right side of the printed wire layer 14 have a scattered light pattern. Light radiates from the light-emitting diodes 12 in multiple directions with different intensities. Therefore, in the prior art, in order to achieve as uniform illumination as possible of the light-emitting thin film 10, either the spacing A between the light-emitting diodes is reduced, or a diffusion layer (not shown) for light scattering is used.

[0043] On the left side of the schematic diagram, a micro-optical layer 18 is connected downstream of the light-emitting diodes 12 in the emission direction R of the thin film. Here, the micro-optical layer 18 has micro-optical structure elements, through which the unidirectionally radiated light of the light-emitting diodes 12 is coupled into the micro-optical layer 18 and deflected by the micro-optical layer 18 on the optical path 20. According to Figure 1 the construction of the micro-optical layer 18 results in mainly unidirectional radiation at the exit of the light from the micro-optical layer 18. Therefore, with the same spacing A between the light-emitting diodes, a higher uniformity of the illumination of the light-emitting thin film can be achieved.

[0044] In addition, in this embodiment, the spacing A between the light-emitting diodes corresponds to the width of the micro-optical region B. The micro-optical region B includes the region of the micro-optical layer 18 in which the incident light is deflected to the light-radiating surface through the micro-optical structure. Figure 1 The juxtaposed micro-optical regions B are shown.

[0045] In addition, according to Figure 1The embodiment has a textile layer / non-woven fabric 22 on the film surface O irradiated with light. The use of such a textile layer / non-woven fabric 22 additionally improves the uniformity of the film illumination by scattering the irradiated light on this surface. Furthermore, the light-emitting film 10 can be designed in terms of acoustic requirements, which further increases the usability of the light-emitting film 12.

[0046] Furthermore, this embodiment has a control device 24, which is electrically connected to the printed conductor layer 14 and is used to control the light-emitting diodes 12. Here, the control device 24 can be implemented as a central control device 24 as shown in the figure, or can be constructed dispersedly by means of a row of control devices close to the light-emitting diodes. Alternatively or additionally, the control device can be arranged on the film surface, in particular on the carrier layer (shown by the dashed line).

[0047] Figure 2 Schematic view showing a second embodiment of the light-emitting film 10 according to the invention. The light-emitting film 10 has a mirror layer 26, which is arranged behind the light-emitting diodes 12 against the radiation direction R of the light-emitting film 10. The micro-optical layer 18 is arranged between the light-emitting diodes 12 and the mirror layer 18. Here, the light radiated by the light-emitting diodes 12 against the radiation direction R of the light-emitting film 10 is deflected against the radiation direction R through the micro-optical layer 18 and is reflected on the mirror layer 25. Here, the reflected light is turned along the radiation direction R and is deflected along the radiation direction R through the micro-optical layer 18 until the radiating surface O. The radiating surface O is here constructed by a light-transmissive, in particular transparent, printed conductor layer 14, which is additionally flocked with a textile layer / non-woven fabric 22. Here, in the case where the thickness of the micro-optical layer is similar to that in Embodiment 1 ( Figure 1 ), the significantly extended optical path 20 due to the reflection on the mirror layer 26 becomes clear (for clarity, only one optical path 20 is provided with a reference numeral).

[0048] Furthermore, the schematic view of the light-emitting film 10 shows overlapping micro-optical regions B. Due to the overlap of the micro-optical regions B, the strongly scattered radiated light, which would conventionally be counted as a loss, can still be deflected particularly effectively onto the radiating surface O. This effect is particularly prominent when the light-emitting diodes 12 are surrounded by the micro-optical layer 18.

[0049] For the purpose of observation, the sketch again shows the beam paths with the influence of the micro-optical layer 18 (the light-emitting diodes 12 are on the left in the schematic view) and without the influence of this micro-optical layer (the light-emitting diodes 12 are on the right in the schematic view).

[0050] Figure 3Schematic diagram showing a third embodiment of the light-emitting thin film 10 according to the present invention. The light-emitting thin film 10 has an additional micro-optical layer 18. The light-emitting diodes 12 and the printed conductor layer 14 are arranged between the two micro-optical layers 18. The printed conductor layer 14 is configured to be light-transmissive, especially transparent, so as not to interfere with transmission. The arrangement of the two micro-optical layers 18 enables the construction of a wide micro-optical region B, and correspondingly, a low density of the light-emitting diodes 12 can be achieved in the case of still uniform illumination of the light-emitting thin film 10 - as illustrated by the light-emitting diode pitch A.

[0051] In addition, it can be seen from the schematic diagram of the light-emitting thin film 10 in Figure 3 that the light radiated by the light-emitting diodes 12 undergoes light deflection by the micro-optical structure of the micro-optical layer 18 not only when radiating in the direction opposite to the radiation direction R of the light-emitting thin film, but also when radiating along the radiation direction R of the light-emitting thin film 10 or transversely to this radiation direction.

[0052] Looking at all the drawings of the drawing, the present invention relates to a light-emitting thin film 10 having a plurality of light-emitting diodes 12, a carrier layer 16, and a light-guiding layer 18 composed of a micro-optical structure, which can achieve turning the light radiated in multiple directions along the common radiation direction R of the light-emitting thin film 10, so as to achieve uniform illumination of the light-emitting thin film surface O at a low light-emitting diode filling rate of the light-emitting thin film 10.

[0053] List of reference numerals

[0054] 10 Light-emitting thin film;

[0055] 12 Light-emitting diode;

[0056] 14 Printed conductor layer;

[0057] 16 Carrier layer;

[0058] 18 Micro-optical layer;

[0059] 20 Optical path;

[0060] 22 Textile layer / non-woven fabric;

[0061] 24 Control device;

[0062] 26 Mirror layer;

[0063] A Pitch of the light-emitting diodes;

[0064] B Width of the micro-optical region;

[0065] O Light-radiating film surface;

[0066] Radiation direction of the R light-emitting thin film.

Claims

1. A multi-layer light-emitting thin film (10), the light-emitting thin film having a plurality of light-emitting diodes (12), a printed wire layer (14), and a carrier layer (16), the printed wire layer being used for electrically connecting the light-emitting diodes (12), wherein, The light-emitting film (10) has a micro-optical layer (18) which has micro-optical structural elements for generating uniform illumination, wherein the light-emitting diodes (12) have a spacing (A) between 8 mm and 100 mm, wherein the micro-optical layer (18) has a structured surface which has repeating micro-optical regions (B), wherein the micro-optical regions (B) are constructed mostly rotationally symmetrically or completely rotationally symmetrically starting from the optical center which is exactly above the light-emitting diodes (12), wherein the micro-optical regions (B) have a larger area than the light-emitting diodes (12), wherein adjacent micro-optical regions (B) overlap, and wherein the light-emitting film (10) is constructed to be wound, wherein the winding radius is between 1 cm and 10 cm.

2. The light-emitting thin film according to claim 1, wherein The light-emitting film (10) has a textile layer or a non-woven fabric layer (22) on the film surface (O) which emits light.

3. The light-emitting thin film according to claim 2, wherein The textile layer or the non-woven fabric layer (22) is formed by flocking of the light-emitting film (10).

4. The light-emitting thin film according to claim 3, wherein, The textile layer or the non-woven fabric layer (22) is formed by flocking of the film surface (O) which emits light.

5. The light-emitting thin film according to any one of claims 1 to 4, characterized in that The micro-optical layer (18) mostly surrounds the light-emitting diodes (12).

6. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The micro-optical layer (18) completely surrounds the light-emitting diodes (12).

7. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The light-emitting film (10) has a mirror layer (26) which is located behind the light-emitting diodes (12) along the radiation direction (R) of the light-emitting film (10).

8. The light-emitting thin film according to claim 7, wherein, The mirror layer (26) and the carrier layer (16) form a common layer.

9. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The light-emitting film (10) has a further micro-optical layer (18) which has micro-optical structural elements, wherein the light-emitting diodes (12) are arranged between two micro-optical layers (18).

10. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The carrier layer (16) is composed of a film, a non-woven fabric, paper and / or a fabric.

11. The light-emitting thin film according to claim 10, wherein, The fabric is a textile.

12. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The printed conductor layer (14) is constructed to be partially transparent.

13. The light-emitting thin film according to any one of claims 1 to 4, wherein, The printed conductor layer (14) is constructed to be completely transparent.

14. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The printed conductor layer (14) is composed of copper, conductive ink, indium zinc oxide and / or silver oxide.

15. The light-emitting thin film according to any one of claims 2 to 4, characterized in that, The textile layer or the non-woven fabric layer (22) is oriented to be unidirectionally transparent.

16. The light-emitting thin film according to claim 15, wherein, The textile layer or the non-woven fabric layer (22) is oriented to be unidirectionally transparent along the radiation direction (R) of the light-emitting film (10).

17. The light-emitting thin film according to any one of claims 2 to 4, characterized in that, The textile layer or the non-woven fabric layer (22) is at least partially acoustically hard and / or at least partially acoustically soft.

18. The light-emitting thin film according to any one of claims 1 to 4, characterized in that, The film thickness is from 0.1 mm to 40 mm.

19. The light-emitting thin film according to claim 18, wherein, The film thickness is from 0.2 mm to 30 mm.

20. The light-emitting thin film according to claim 19, wherein, The film thickness is from 0.3 mm to 20 mm.

Images