EP2758708B1 - Reflective beam shaper for producing a desired emission characteristic from an emission characteristic of a surface light source - Google Patents

Description

Embodiments of the present invention relate to a reflective beamformer for generating a desired radiation characteristic from a radiation characteristic of a surface light source. Further embodiments of the present invention relate to a reflective beam shaper for setting arbitrarily directed emission profiles of surface light sources.

For the design of special light distributions, various lighting devices are used in the prior art.

Known pyramidal refractive structures provide, for example, angular distributions in one or two directions, which can be limited to approximately + 30 °. For example, 1D prisms, 2D prisms or crossed 1D prisms, as described, for example, in US Pat WO 2006/073916 A1 is described. With known one-dimensional refractive prism arrays, for example, deflections of about 20 ° can be achieved.

The US 2011/0018009 A1 describes, for example, a selective mirroring of partial areas in prismatic 1D arrays, which allows larger deflection angles and allows design possibilities for beam shaping in one direction.

In the US 7,706,073 B2 For example, it is described how the use of arrays of microlenses and diaphragms with the same center positions can achieve a very clear restriction of the light distribution ("collimation").

In the DE 10 2009 016 234 A1 For example, it is described how, by means of suitable diaphragm shapes and their arrangement, largely any radiation characteristics can be set relative to microlenses or refractive free-form elements.

However, a general problem with the known concepts described above for producing a desired emission characteristic is that the emission characteristic can only be adjusted to a limited extent and precise alignment of several to the other Forming the radiation characteristic necessary various functional levels, such as diaphragms and lenses or free-form elements, is difficult.

The WO 2008/122907 A2 describes a light emitting device comprising a layer stack including an organic light emission layer disposed between two electrode layers, wherein a shielding structure is arranged on the layer stack having a plurality of fin elements extending in a sheet shape from the layer stack in such a manner that the fin elements lead the artificially generated light of the organic light emission layer from the light emitting device. The lamellar elements are attached to the layer stack via a fastening device not described in detail.

The object of the present invention is therefore to provide a reflective beam shaper, which allows a more flexible adjustability of a radiation characteristic and at the same time is distinguished by a simplified or even more reliable design.

This object is achieved by a reflective beam shaper according to claim 1.

Embodiments of the present invention provide a reflective beamformer for generating a desired radiation characteristic from an emission characteristic of a surface light source having a beam-forming laminar structure with a plurality of light-transmitting beam-shaping openings. Here, the light-transmitting beam shaping openings extend from a first side facing the surface light source to a second side opposite the first side through the beam-forming planar structure. Furthermore, the translucent beam shaping openings have reflective side walls. A lateral extent of the translucent beam-forming openings on the first side of the beam-forming planar structure is smaller than a lateral extent of the transparent beam-forming openings on the second side of the beam-forming planar structure, such that the emission characteristic of the planar light source changes to the desired radiation characteristic as it passes through the beam-forming planar structure becomes.

The core idea of the present invention is that the above-mentioned more flexible adjustability of the radiation pattern can be achieved with a simultaneously simplified or even more reliable design of the reflective beam shaper, if transparent beam shaping openings with reflective side walls are provided and a lateral extent of the transparent beam shaping openings the first side of the beam-forming areal structure is smaller than a lateral extent of the translucent beam-forming openings on the second side of the beam-forming areal structure. As a result, the emission characteristic of the surface light source can be changed to the desired emission characteristic as it passes through the beam-forming planar structure. Thus, on the one hand, the more flexible adjustability of the emission characteristic can be achieved and, on the other hand, a high outlay for the precise alignment of different functional levels of the beam former can be avoided at the same time. In this case, use can be made of translucent beam shaping openings having reflective side walls and at the same time a selected ratio between a lateral extent of the translucent beam forming openings on the first side of the beam-forming planar structure and a lateral extension of the transparent beam-forming openings on the second side of the beam-forming sheet-like structure can be used.
In further embodiments of the present invention, the translucent beam shaping apertures of the beam-forming sheet structure are inclined at a predetermined angle of inclination to a normal of the beam-forming sheet-like structure. Due to the inclination of the light-transmitting beam shaping openings in the beam-forming planar structure, the emission characteristic generated by the reflective beamformer can be adjusted so that, for example, a predetermined emission angle or a predetermined deflection of a center of gravity of an angular distribution can be obtained. According to the invention, the beam-forming planar structure is reflective on the first side thereof. Thus, light rays emitted from the surface light source in the direction of the beam-forming sheet structure can be reflected back to the surface light source on the first side of the beam-forming sheet structure. The light beams reflected to the surface light source can in turn be reflected at the surface light source in the direction of the beam-forming planar structure. As a result, multiple reflections (multiple reflections) of the light beams emitted by the area light source can be generated between the beam-forming areal structure and the area light source, so that an efficient utilization of the amount of light or an efficient "light recycling" can be obtained.
In other embodiments of the present invention, the ratio between the lateral extent of the translucent beamforming apertures on the first side and the lateral extent of the transmissive beamforming apertures on the second side or the inclination angle of the translucent beamforming apertures changes laterally between adjacent translucent beamforming apertures. By the lateral change of the ratio between the lateral extent of the translucent beam shaping openings on the first side and the lateral extent of the translucent beam shaping openings on the second side or the angle of inclination, a location-dependent emission characteristic or angular distribution can be realized.

Further embodiments of the present invention provide a system with a reflective beam shaper, which further comprises a further inventive reflective beam shaper, wherein the surface light source is a two-sided radiating surface light source, for example. An OLED (organic light emitting diode), between the reflective beam shaper and the further reflective beam shaper is arranged. By arranging the surface emitting light source radiating on both sides between the reflective beam shaper and the further reflective beam shaper, the radiation characteristic of the surface light source radiating on both sides can be adjusted as it passes through the beam-forming planar structure of the reflective beam shaper and the beam-forming surface structure of the further reflective beam shaper. Thus, in a two-sided radiating surface light source, the desired radiation characteristic in a first half-space adjacent to a first side of the surface light source and in a second half-space adjacent to one of the first side opposite second side of the surface light source can be generated.

Fig. 1

eine Seitenansicht eines reflektiven Strahlformers gemäß einem Ausführungsbeispiel der vorliegenden Erfindung;

Fig. 2a

eine Seitenansicht eines reflektiven Strahlformers gemäß einem weiteren Ausführungsbeispiel der vorliegenden Erfindung;

Fig. 2b

eine perspektivische Ansicht des Ausführungsbeispiels des reflektiven Strahlformers gemäß Fig. 2a;

Fig. 3a-3f

Draufsichten von lichtdurchlässigen Strahlformungsöffnungen mit zueinander kongruenten Querschnitten gemäß Ausführungsbeispielen der vorliegenden Erfindung;

Fig. 4a-4d

Seitenansichten von lichtdurchlässigen Strahlformungsöffnungen mit einer sich ändernden lateralen Ausdehnung gemäß Ausführungsbeispielen der vorliegenden Erfindung;

Fig. 4e-4h

Seitenansichten von lichtdurchlässigen Strahlformungsöffnungen mit einer sich ändernden lateralen Ausdehnung gemäß weiteren Ausführungsbeispielen der vorliegenden Erfindung;

Fig. 5a

eine Draufsicht eines Ausführungsbeispiels von lichtdurchlässigen Strahlformungsöffnungen in einem hexagonalen Gitter;

Fig. 5b

eine Draufsicht eines Ausführungsbeispiels von lichtdurchlässigen Strahlformungsöffnungen in einem quadratischen Gitter;

Fig. 5c

eine Draufsicht eines Ausführungsbeispiels von lichtdurchlässigen Strahlformungsöffnungen in einem rhombischen Gitter;

Fig. 6

eine Seitenansicht eines reflektiven Strahlformers gemäß einem weiteren Ausführungsbeispiel der vorliegenden Erfindung;

Fig. 7a,b

Seitenansichten von reflektiven Strahlformern gemäß weiteren Ausführungsbeispielen der vorliegenden Erfindung;

Fig. 8a,b

Seitenansichten von reflektiven Strahlformern gemäß weiteren Ausführungsbeispielen der vorliegenden Erfindung;

Fig. 9

eine Seitenansicht eines Systems mit zwei erfindungsgemäßen reflektiven Strahlformern zum Einstellen einer Abstrahlcharakteristik einer beidseitig abstrahlenden OLED; und

Fig. 10a,b

schematische Darstellungen zur Veranschaulichung einer Abstrahlcharakteristik eines erfindungsgemäßen reflektiven Strahlformers.

Embodiments of the present invention will be explained in more detail below with reference to the accompanying figures, in which identical or equivalent elements are designated by the same reference numerals. Show it:

Fig. 1

a side view of a reflective beamformer according to an embodiment of the present invention;

Fig. 2a

a side view of a reflective beam former according to another embodiment of the present invention;

Fig. 2b

a perspective view of the embodiment of the reflective beam shaper according to Fig. 2a ;

Fig. 3a-3f

Top views of translucent beam forming openings with mutually congruent cross-sections according to embodiments of the present invention;

Fig. 4a-4d

Side views of translucent beam shaping apertures with a varying lateral extent according to embodiments of the present invention;

Fig. 4e-4h

Side views of translucent beam forming openings with a varying lateral extent according to further embodiments of the present invention;

Fig. 5a

a plan view of an embodiment of translucent beam forming openings in a hexagonal grid;

Fig. 5b

a plan view of an embodiment of translucent beam shaping openings in a square grid;

Fig. 5c

a plan view of an embodiment of translucent beam forming openings in a rhombic grid;

Fig. 6

a side view of a reflective beam former according to another embodiment of the present invention;

Fig. 7a, b

Side views of reflective beamformers according to further embodiments of the present invention;

Fig. 8a, b

Side views of reflective beamformers according to further embodiments of the present invention;

Fig. 9

a side view of a system with two reflective beam shapers according to the invention for adjusting a radiation characteristic of a double-sided radiating OLED; and

Fig. 10a, b

schematic representations to illustrate a radiation characteristic of a reflective beam shaper according to the invention.

Before the present invention is explained in more detail below with reference to the figures, it is pointed out that in the exemplary embodiments illustrated below, identical elements or functionally identical elements in the figures are provided with the same reference numerals. A description of elements with the same reference numerals is therefore interchangeable and / or applicable to each other in the various embodiments.

Fig. 1 shows a side view of a reflective beamformer 100 according to an embodiment of the present invention. As in Fig. 1 1, the reflective beam former 100 has a beam-forming planar structure 110 with a plurality of light-transmitting beam shaping openings 115. In this case, the light-transmitting beam shaping openings 115 extend from the first side 112 facing the surface light source 105 to the second side 114 opposite the first side 112 through the beam-forming planar structure 110. Furthermore, the transparent beam-forming openings 115 have reflective side walls 117. At the in Fig. 1 In the embodiment shown, a lateral extent L1 of the translucent beam shaping openings 115 on the first side 112 of the beam-forming planar structure 110 is smaller than a lateral extent L2 of the translucent beam shaping openings 115 on the second side 114 of the beam-forming planar structure 110. This makes it possible for the emission characteristic the surface light source 105 can be changed to the desired radiation characteristic when passing through the beam-forming planar structure 110.

In Fig. 1 For example, a coordinate system 104 having first, second, and third axes 101, 102, 103 is shown. Here, the first and second axes 101, 102 (x, y axes) of the coordinate system 104 are substantially parallel to a surface of the beam-forming sheet 110, while the third axis 103 of the coordinate system 104 (z-axis) is substantially perpendicular to the surface of the jet-forming sheet-like structure 110. Further, a first lateral direction (x direction) corresponds to a direction parallel to the first axis 101 (x axis) of the coordinate system 104 and a second lateral direction (y direction) to a direction parallel to the second axis 102 (y axis) of the coordinate system 104, while a vertical direction (z-direction) corresponds to a direction parallel to the third axis 103 of the coordinate system 104. In Fig. 1 is the first lateral direction parallel to the plane of the drawing, while the second lateral direction is perpendicular to the plane of the drawing. The plane (x, y plane) spanned by the first and second axes 101, 102 of the coordinate system 104 is substantially parallel to the surface or areal extent of the beam-forming planar structure 110. Furthermore, a lateral extent extends along one lateral direction (eg in the x-direction, in the y-direction or in any other direction in the x, y plane), while a vertical extension along the vertical direction (or along the thickness direction of the beam-forming planar structure 110). As in the embodiment of Fig. 1 4, the lateral extent of the translucent beam forming openings 115 changes in the vertical direction (ie, z-dependent), so that the lateral extent L1 is smaller than the lateral extent L2.

In embodiments, the radiation characteristic of the area light source 105 may be characterized by a Lambertian directional distribution.

At the in Fig. 1 In the embodiment shown, the ratio between the lateral extent L1 of the translucent beam shaping apertures on the first side 112 of the beam-forming planar structure 110 and the lateral extent L2 of the translucent beam-forming apertures 115 on the second side of the beam-forming planar structure 110 (aperture ratio) can be selected such that the desired emission characteristic of the reflective beamformer 100 can be obtained. By providing a selected aperture ratio, a high outlay for the precise alignment of different functional planes of the beam former can be avoided. At the same time, a more flexible adjustability of the emission characteristic can be achieved by adjusting the aperture ratio for the respective emission characteristic.

Furthermore, in the in Fig. 1 In the embodiment shown, the reflecting sidewalls 117 of the translucent beam forming ports 115 are used to reflect light beams 111 radiated from the area light source 105 and reflected on the reflecting sidewalls 117 of the translucent beam forming ports 115 as they pass through the beam-forming laminar structure 110, respectively in a predetermined direction deflect, so that the desired radiation characteristic can be generated. In Fig. 1 the reflections of the light rays 111 on the reflective sidewalls 117 of the translucent beam shaping apertures 115 are indicated by the dashed arrows.

Fig. 2a shows a side view of a reflective beam shaper 200 according to another embodiment of the present invention. The in Fig. 2a Reflective beamformer 200 shown substantially corresponds to that in FIG Fig. 1 The reflective beamformer 100 shown in FIG Fig. 2a The reflective beamformer 200 shown in FIG. 2, the transparent beam shaping openings 115 of the beam-forming sheet-like structure 110 at a predetermined inclination angle α against a normal 201 of the beam-forming sheet-like structure 110 inclined.

In Fig. 2a is again the coordinate system 104 of Fig. 1 wherein the first and second axes 101, 102 of the coordinate system 104 are parallel to the surface of the beam-forming sheet-like structure 110, while the third axis 103 of the coordinate system 104 is perpendicular to the surface Expansion of the beam-forming sheet-like structure 110 is. As in Fig. 2a 2, the normal 201 extends in the vertical direction and serves as a reference for the angle of inclination α of the translucent beam shaping openings 115 Fig. 2a In the exemplary embodiment shown, the angle of inclination α can be determined by a straight line (dashed line 215), the straight line passing through a first center 211 of one of the translucent beam forming openings 115 on the first side 112 and a second center 213 of the respective translucent beam forming openings 115 on the second side 114 is defined. From the predetermined angle of inclination α of the translucent beam shaping apertures 115 results in a given thickness D of the beam-forming sheet-like structure 110 dependent on the inclination angle α length L of the translucent beam forming openings 115 along the dashed line 215th From this length L in turn depends on the emission, the can be generated with the reflective beam shaper 200. Thus, by the inclination of the translucent beam forming openings 115 at the predetermined inclination angle α, the radiation characteristic of the reflective beam former 200 can be adjusted. For example, in this case, a predetermined emission angle or a predetermined deflection of a center of gravity of an angular distribution can be obtained.

Fig. 2b shows a perspective view of the embodiment of the reflective beam shaper 200 according to Fig. 2a , In the perspective view of Fig. 2b For example, the translucent beam shaping openings 115 that extend through the beam-forming planar structure 210 from the first to the second side 112, 114 can be seen. Furthermore, in Fig. 2b in turn, the coordinate system 104 of Fig. 1 shown. At the in Fig. 2b In the exemplary embodiment shown, the reflective beamformer 200 has a two-dimensional arrangement of translucent beam-forming openings 115 arranged regularly adjacent to one another in the beam-forming planar structure 210. As it is in Fig. 2b For example, the first and second axes 101, 102 of the coordinate system 104 may be along the regularly juxtaposed translucent beam forming apertures 115 in the two-dimensional array (or grid) of FIG Fig. 2b be aligned. Due to the two-dimensional arrangement of transparent beam shaping openings 115 according to FIG Fig. 2b For example, the radiation characteristic of the surface light source 105 (not shown in FIG. 2) arranged below the beam-forming planar structure 210 may be used Fig. 2b ) without having to precisely align different functional planes in the beam-forming sheet 210 of the reflective beam former 200. Thus, a high cost for the precise alignment of different functional levels of the beam former can be avoided.

Fig. 3a to 3f show plan views of translucent beam forming ports 310; 320; 330; 340; 350; 360 with mutually congruent cross sections 312, 314; 322, 324; 332, 334; 342, 344; 352, 354; 362, 364 according to embodiments of the present invention. In the Fig. 3a to 3f The translucent beam shaping apertures 310, 320, 330, 340, 350, 360 shown in FIG Fig. 1 shown translucent beam shaping openings 115 of the reflective beam shaper 100. In Fig. 3a to 3f are the first and second axes 101, 102 of the coordinate system 104 of FIG Fig. 1 shown. In this case, the first and second axes 101, 102 of the coordinate system 104 span the x, y plane. At the in Fig. 3a to 3f In the embodiments shown, the light-transmitting beam shaping openings 310, 320, 330, 340, 350, 360 of the beam-forming planar structure 110 on the first and second sides 112, 114 thereof have first and second cross-sections 312, 314, respectively; 322, 324; 332, 334; 342, 344; 352, 354; 362, 364, which have a round, elliptical, quadrangular or polygonal shape (or any other shape) and are congruent to each other and offset or centered in the lateral direction. In this case, the lateral direction corresponds in turn to a direction parallel to the x, y plane which is spanned by the first and second axes 101, 102 of the coordinate system 104. The lateral offset of the staggered cross sections is z. In x, y, or any other lateral direction in the x, y plane.

In the top view of Fig. 3a For example, one of the translucent beam-shaping openings 310 with mutually congruent cross-sections (first and second cross-section 312, 314) is shown in the beam-forming planar structure 110. At the in Fig. 3a 1 and 2, the first and second cross-sections 312, 314 on the first and second sides of the jet-forming sheet-like structure 110 each have a round shape (for example, a circular shape). Here, the first and the second cross-section 312, 314 are arranged centered in the lateral direction.

In the top view of Fig. 3b For example, one of the translucent beam-forming openings 320 with mutually congruent cross-sections (first and second cross-section 322, 324) is shown in the beam-forming sheet-like structure 110. At the in Fig. 3b 1 and 2, the first and second cross-sections 322, 324 on the first and second sides of the jet-forming sheet-like structure 110 each have a quadrangular shape (eg, rectangular shape). Here, the first and the second cross section 322, 324 are arranged centered in the lateral direction.

In the top view of Fig. 3c is one of the translucent beam-shaping openings 330 with mutually congruent cross-sections (first and second cross-section 332, 334) in the beam-forming sheet-like structure 110. At the in Fig. 3c 1 and 2, the first and second cross-sections 332, 334 on the first and second sides of the jet-forming sheet-like structure 110 each have a polygonal shape (eg, hexagonal shape). Here, the first and the second cross section 332, 334 are centered in the lateral direction.

In the top view of Fig. 3d For example, one of the translucent beam-shaping openings 340 is shown with congruent cross-sections (first and second cross-sections 342, 344) in the beam-forming sheet-like structure 110. At the in Fig. 3d In the embodiment shown, the first and second cross-sections 342, 344 on the first and second sides of the jet-forming sheet-like structure 110 each have an elliptical shape. As in Fig. 3d As shown, the first and second cross-sections 342, 344 are offset from one another in the lateral direction.

In the top view of Fig. 3e For example, one of the translucent beam-shaping openings 350 is shown with congruent cross-sections (first and second cross-sections 352, 354) in the beam-forming sheet-like structure 110. At the in Fig. 3e 1 and 2, the first and second cross-sections 352, 354 on the first and second sides of the jet-forming sheet-like structure 110 each have a quadrangular shape (eg, rectangular shape). As in Fig. 3e As shown, the first and second cross-sections 352, 354 are staggered in the lateral direction.

In the top view of Fig. 3f For example, one of the translucent beam-shaping apertures 360 is shown with cross-sections (first and second cross-sections 362, 364) congruent to each other in the beam-forming sheet-like structure 110. At the in Fig. 3f 1 and 2, the first and second cross-sections 362, 364 on the first and second sides of the jet-forming sheet-like structure 110 each have a polygonal shape (eg, hexagonal shape). As in Fig. 3f As shown, the first and second cross-sections 362, 364 are staggered in the lateral direction.

In further embodiments, the mutually congruent cross sections may each have a circular shape and be arranged offset in the lateral direction against each other.

In further embodiments, the mutually congruent cross sections may each have an elliptical shape and be centered in the lateral direction.

Further, in other embodiments, any other shapes may be provided for the mutually congruent cross-sections, which may be offset or centered in the lateral direction.

In further alternative embodiments, the cross-sections of the translucent beam shaping apertures on the first and second sides of the beam-forming laminar structure may be similar or different from each other.

According to the in Fig. 3a to 3f As shown, various implementations of the translucent beam shaping apertures can be realized. In this case, the cross sections of the same on the first and the second side of the beam-forming planar structure, for example, congruent to each other and offset in the lateral direction against each other or centered. The various implementations for the light-transmitting beam shaping openings can achieve a more flexible adjustment of the emission characteristic produced by the reflective beamformer. Thus, it becomes possible that essential parameters of the radiation characteristic, such as the radiation angle or the deflection of the center of gravity of the angular distribution, can be set more easily or even more precisely.

Fig. 4a to 4d 11 show side views of translucent beam shaping openings 410, 420, 430, 440 with a varying lateral extent S according to exemplary embodiments of the present invention. In the Fig. 4a to 4d The translucent beam shaping openings 410, 420, 430, 440 shown in FIG. 2 essentially correspond to the transparent beam shaping openings 115 of the reflective beam former 100 in FIG Fig. 1 , In the side views of Fig. 4a to 4d is the third axis 103 of the coordinate system 104 of Fig. 1 shown.

The lateral extent S extends along a lateral direction (eg in the x-direction, in the y-direction or in any other direction in the x, y plane). For a circular cross section of the transparent beam shaping openings, the lateral extent S is defined, for example, by a diameter of the circular cross section. In the case of an elliptical cross section of the transparent beam shaping openings, the lateral extent S is defined, for example, by a main axis of the elliptical cross section. For a rectangular cross-section of the transparent beam-shaping openings, the lateral extent S is defined, for example, by a length of the rectangular cross-section. Finally, in any free-form cross-section of the translucent beam shaping openings, the lateral extent S for example, defined by a maximum lateral extent of the respective free-form cross section in the x, y plane.

At the in Fig. 4a In the embodiment shown, the lateral extent of the translucent beam shaping openings 410 changes linearly from the first to the second side 112, 114 or in the vertical direction parallel to the third axis 103. Here, the transparent beam-shaping openings 410 of the beam-forming planar structure 110 have no inclination against the normal 201 of the beam-forming planar structure 110.

At the in Fig. 4b In the embodiment shown, the lateral extent of the translucent beam shaping openings 420 changes from the first to the second side 112, 114 or in the vertical direction parallel to the third axis 103 hyperbolic. In this case, the light-permeable beam-forming openings 420 of the beam-forming planar structure 110 in turn have no inclination against the normal 201 of the beam-forming planar structure 110.

At the in Fig. 4c In the embodiment shown, the lateral extent of the translucent beam shaping openings 430 changes parabolically from the first to the second side 112, 114 or in the vertical direction parallel to the third axis 103. In this case, the transparent beam-shaping openings 430 of the beam-forming planar structure 110 in turn have no inclination against the normal 201 of the beam-forming planar structure 110.

At the in Fig. 4d In the embodiment shown, the lateral extent of the translucent beam shaping openings 440 changes from the first to the second side 112, 114 or segmented in a vertical direction parallel to the third axis 103. In this case, the light-transmitting beam-shaping openings 440 of the beam-forming planar structure 110 in turn have no inclination against the normal 201 of the beam-forming planar structure 110.

4e to 4h 10 show side views of translucent beam shaping openings 450, 460, 470, 480 with a varying lateral extent S according to further exemplary embodiments of the present invention. In the 4e to 4h The translucent beam shaping apertures 450, 460, 470, 480 shown in FIG. 2 essentially correspond to the translucent beam shaping apertures 115 of the reflective beam former 100 of FIG Fig. 1 , In the side views of 4e to 4h is again the third axis 103 of the coordinate system 104 of Fig. 1 shown.

At the in Fig. 4e In the embodiment shown, the lateral extent of the translucent beam shaping openings 450 changes similarly to that in FIG Fig. 4a shown embodiment of the first to the second side 112, 114 and in the vertical direction parallel to the third axis 103 is substantially linear. In this case, however, the translucent beam-forming openings 450 of the beam-forming planar structure 110 are inclined at the same time at the predetermined inclination angle α against the normal 201 of the beam-forming planar structure 110.

At the in Fig. 4f In the embodiment shown, the lateral extent of the translucent beam shaping openings 460 changes in a manner similar to that in FIG Fig. 4b shown embodiment of the first to the second side 112, 114 and in the vertical direction parallel to the third axis 103 is substantially hyperbolic. In this case, however, the translucent beam-forming openings 460 of the beam-forming planar structure 110 are inclined at the same time at the predetermined inclination angle α against the normal 201 of the beam-forming planar structure 110.

At the in Fig. 4g In the embodiment shown, the lateral extent of the translucent beam shaping openings 470 changes in a manner similar to that in FIG Fig. 4g shown embodiment of the first to the second side 112, 114 and in the vertical direction parallel to the third axis 103 is substantially parabolic. In this case, however, the translucent beam-forming openings 470 of the beam-forming planar structure 110 are inclined at the same time at the predetermined inclination angle α against the normal 201 of the beam-forming planar structure 110.

At the in Fig. 4h In the embodiment shown, the lateral extent of the translucent beam shaping openings 480 changes similarly to that in FIG Fig. 4d shown embodiment of the first to the second side 112, 114 and in the vertical direction parallel to the third axis 103 is substantially segmented. In this case, however, the translucent beam-forming openings 480 of the beam-forming planar structure 110 are simultaneously inclined at a predetermined inclination angle α to the normal 201 of the beam-forming planar structure 110.

Thus, in embodiments according to Fig. 4a to 4d the lateral extent S of the translucent beam-forming openings 410; 420; 430; 440 from the first to the second side 112, 114 linearly, hyperbolic, parabolic or segmented change (or otherwise suitably change). In further embodiments according to 4e to 4h For example, the translucent beam forming ports 450; 460; 470; 480 at the same time be inclined at the predetermined inclination angle α against the normal 201 of the beam-forming sheet-like structure 110.

By respectively providing a characteristic change in the lateral extent of the light-transmitting beam-shaping openings in the vertical direction, different contours thereof can be obtained, which can be used to adjust the emission characteristic differently, respectively. Thus, in embodiments according to Fig. 4a to 4d or 4e to 4h the more flexible adjustability of the emission characteristic generated by the reflective beamformer can be achieved. For example, it is therefore possible to considerably improve the generation of the desired radiation characteristic of the reflective beam former by the use of different contours of the transparent beam shaping openings.

Fig. 5a to 5c show plan views of various embodiments of translucent beam forming apertures 515; 525; 535 in different grid arrangements. In the plan views of Fig. 5a to 5c are the first and second axes 101, 102 of the coordinate system 104 of FIG Fig. 1 shown. In this case, the first and second axes 101, 102 of the coordinate system 104 span the x, y plane. In the Fig. 5a to 5c shown translucent beam shaping openings 515; 525; 535 substantially correspond to the transparent beam shaping openings 115 of the reflective beam former 100 of FIG Fig. 1 , Referring to Fig. 5a to 5c form the translucent beam forming openings 515; 525; 535 each have a regular two-dimensional arrangement (grid or array). In the plan views of Fig. 5a to 5c is only the second side 114 of the beam-forming sheet-like structure 110 with the translucent beam forming openings 515; 525; 535 recognizable.

Fig. 5a shows a plan view of an embodiment of transparent beam shaping openings 515 in a first arrangement 510 or in a hexagonal grid. As in Fig. 5a 2, the translucent beam-forming openings 515 of the beam-forming laminar structure 110 on the second side 114 of the same are regularly arranged next to one another. Here, the first arrangement 510 of Fig. 5a characterized in that the translucent beam shaping apertures 515 form a hexagonal grid. In the embodiment according to Fig. 5a For example, the translucent beam-forming apertures 515 on the second side 114 may have a round shape such that the first array 510 formed by the translucent beam-forming apertures 515 has hexagonal symmetry (hexagonal grating or hexagonal symmetry grating).

Fig. 5b shows a plan view of an embodiment of translucent beam shaping openings 525 in a second arrangement 520 or in a square grid. As in Fig. 5b 2, the translucent beam-forming openings 525 of the beam-forming planar structure 110 on the second side 114 of the same are regularly arranged next to each other. Here, the second arrangement 520 of Fig. 5b characterized in that the translucent beam shaping openings 525 form a square grid. In the embodiment according to Fig. 5b For example, the translucent beam-forming apertures 525 on the second side 114 may have a round shape, such that the second array 520 formed by the translucent beam-forming apertures 520 may have a square symmetry (square grid or quadratic symmetry grating).

Fig. 5c shows a plan view of an embodiment of translucent beam shaping openings 535 in a third arrangement 530 or in a rhombic grid. As in Fig. 5c The translucent beam shaping openings 535 of the beam-forming planar structure 110 on the second side 114 of the same are regularly arranged next to each other. Here, the third arrangement 530 of Fig. 5c characterized in that the translucent beam shaping openings 535 form a rhombic grid. In the embodiment according to Fig. 5c For example, the translucent beam shaping openings 535 on the second side 114 may have an elliptical shape such that the third arrangement 530 formed by the translucent beam shaping openings 535 has a rhombic symmetry (rhombic grating or rhombic symmetry grating).

Thus, at the in Fig. 5a to 5c shown embodiments, the translucent beam forming openings 515; 525; 535 of the beam-forming sheet-like structure 110 on the second side 114 thereof are regularly arranged next to one another, the regular arrangement 510; 520; 530 is, for example, a hexagonal, square, or rhombic, or triangular grid (or otherwise a grid filling the area). The regular arrangements 510; 520; 530 from Fig. 5a to 5c may have any orientation or orientation (grid orientation) in the x, y plane. In this case, the grid orientation can be defined, for example, with respect to the border of the area light source. In embodiments, the arrangements should be suitably oriented with respect to the border of the area light source, so that efficient beam shaping of the light beams emitted by the area light source is made possible. Furthermore, in other embodiments, any other arrangements, such as periodic or quasi-periodic arrangements with different lattice symmetries, are possible.

In the Fig. 5a to 5c shown arrangements 510; 520; 530 are advantageous in that they allow a high or maximum transmission of the entire structure or of the reflective beam former. For this purpose, the light-transmitting beam shaping openings 515; 525; 535 on the second side 114 of the jet-forming planar structure 110 or the outlet openings cover as large a part of the overall structure as possible. As a result of the various regular arrangements with different lattice symmetries, the transmission through the beam-forming planar structure of the reflective beam shaper can thus be optimized so that an improved emission characteristic of the same can be generated.

Fig. 6 shows a side view of a reflective beam shaper 600 according to another embodiment of the present invention. The in Fig. 6 Reflective beamformer 600 shown substantially corresponds to the reflective beamformer 100 in FIG Fig. 1 , In the side view of Fig. 6 is the coordinate system 104 of Fig. 1 shown. In the embodiment according to Fig. 6 For example, the reflective beam shaper 600 has two adjacent translucent beam shaping ports 615-1, 615-2. The two adjacent translucent beam shaping ports 615-1, 615-2 of FIG Fig. 6 essentially correspond to the transparent beam shaping openings 115 of the reflective beam former 100 of FIG Fig. 1 ,

As it is in Fig. 6 is exemplified, the reflective beam shaper 600 may be designed so that between the adjacent transparent beam shaping openings 615-1, 615-2, the ratio between the lateral extent L1, L1 'of the transparent beam shaping openings 615-1, 615-2 on the first 112 and the lateral extent L2, L2 'of the translucent beam shaping openings 615-1, 615-2 on the second side 114 changes laterally. In other words, the ratio between the lateral extent L1 of a first of the two adjacent translucent beamforming apertures 615-1, 615-2 on the first side 112 and the lateral extent L2 of the first of the two adjacent translucent beamforming apertures 615-1, 615-2 on the first The second side 114 (aperture ratio L1 / L2) differs from the ratio between the lateral extent L1 'of a second of the two adjacent translucent beam shaping ports 615-1, 615-2 on the first side 112 and the lateral extent L2' of the second of the two adjacent ones translucent beam forming ports 615-1, 615-2 on the second side 114 (opening ratio L1 '/ L2').

Further, in other embodiments, the reflective beam shaper 600 may be configured such that the angle of inclination (α, α ') of the translucent beam forming ports 615-1, 615-2 changes laterally.

According to embodiments, the lateral change of the ratio or the pitch angle or the inclination angle along a lateral direction, such. In the x-direction, in the y-direction or in any other direction in the x, y plane. In this case, the lateral change, for example in the x-direction and in the y-direction may be the same or, for example, different in both directions.

The lateral change of the ratio of the opening ratio or the inclination angle is in FIG Fig. 6 indicated by the dotted line 611, which is substantially parallel to the first axis 101 of the coordinate system 104. By the lateral change of the opening ratio or the inclination angle or by a variation of parameters of the transparent beam shaping openings in a lateral direction, location-dependent emission characteristics can be realized. Thus, it is possible that not only location-independent, but also location-dependent emission characteristics or angular distributions can be generated with the reflective beam shaper. This additionally increases the flexibility of the adjustability of the emission characteristic generated by the reflective beamformer.

According to further embodiments, in the in Fig. 6 Reflective beam shaper 600 shown, the ratio between the lateral extent (L1, L1 ') of the translucent beam forming openings 615-1, 615-2 on the first side 112 and the lateral extent (L2, L2') of the transparent beam shaping openings 615-1, 615- 2 on the second side 114 become larger or smaller in a lateral direction. In other words, the opening ratio L1 / L2 defined by the first of the two adjacent transparent beam-forming openings 615-1, 615-2 may differ from the opening ratio L1 '/ L2 defined by the second of the two adjacent transparent beam-forming openings 615-1, 615-2 'differ. Furthermore, according to further embodiments in the in Fig. 6 shown reflective beam shaper 600, the inclination angle (α, α ') of the transparent beam shaping openings 615-1, 615-2 in a lateral direction become larger or smaller. By increasing or decreasing the aperture ratio or the angle of inclination in the lateral direction, the spatial dependence of the emission characteristic generated by the reflective beamformer can be adjusted or adapted to a predetermined emission characteristic.

In some embodiments, in the in Fig. 6 Reflective beam shaper 600 shown, the ratio between the lateral extent (L1, L1 ') of the translucent beam forming openings 615-1, 615-2 on the first side 112 and the lateral extent (L2, L2') of the translucent beam forming openings (615-1, 615 -2) on the second side 114 and / or the inclination angle (α, α ') of the translucent beam forming openings 615-1, 615-2 monotonically increase or decrease in a lateral direction. However, the lateral change of the opening ratio or the inclination angle need not be monotone, but may also be periodic, quasi-periodic or segmented.

Fig. 7a, b 12 show side views of reflective beamformers 700-1, 700-2 according to further embodiments of the present invention. In the Fig. 7a, b The reflective beamformers 700-1, 700-2 shown in FIG. 1 essentially correspond to the reflective beamformer 100 in FIG Fig. 1 , In the side views of Fig. 7a, b is the coordinate system 104 of Fig. 1 shown.

At the in Fig. 7a, b In the exemplary embodiments shown, the beam-forming planar structure 710-1 of the reflective beamformer 700-1 (FIG. Fig. 7a ) and the beam-shaping areal structure 710-2 of the reflective beamformer 700-2 (FIG. Fig. 7b ) on the first side 112 and 712 of the same reflective. By virtue of the fact that the beam-shaping areal structure 710-1; 710-2 on the first page 112; 712 thereof, light rays emitted from the surface light source 105 toward the beam-forming sheet 710-1; 710-2, at the first side 112; 712 (reflecting side) of the beam-forming sheet 710-1; 710-2 are reflected back to the area light source 105 again. The light rays 711 reflected to the surface light source 105 can in turn be directed to the surface light source 105, which has its own reflectivity, in the direction of the beam-forming planar structure 710-1; 710-2 are reflected. As a result, multiple reflections of the light beams emitted by the surface light source 105 can occur between the reflective beam shaper 710-1; 710-2 and the area light source 105 form. Due to the multiple reflections thus generated, the amount of light available can be better utilized, so that finally an efficient light recycling is obtained. Thus, the in Fig. 7a b embodiments shown reflective reflectors 700-1; 700-2, which are based on efficient light recycling and with which a high luminous efficacy can be obtained.

According to further embodiments, in the in Fig. 7b shown reflective beam shaper 700-2, the first side 712 of the beam-forming planar structure 710-2 between the translucent beam forming openings 115, for example, concave or be convex. Furthermore, according to further embodiments, the first side 112; 712 between the translucent beam shaping openings 115 also have any other curvature or curvature. By the concave or convex curvature of the first side 712 of the beam-forming planar structure 710-2, for example, an angular mixing of the reflected light component can be achieved, whereby the efficiency of the light recycling can be further increased.

Fig. 8a, b show side views of reflective beamformers 800-1; 800-2 according to further embodiments of the present invention. The reflective beam former 800-1 in Fig. 8a includes, for example, the beam-forming planar structure 710-1 of Fig. 7a and a surface light source 805. The reflective beam shaper 800-2 in FIG Fig. 8d includes, for example, the beam-forming planar structure 710-2 of Fig. 7b and the area light source 805. In Fig. 8a, b is the coordinate system 104 of Fig. 1 shown. Referring to Fig. 8a, b For example, the area light source 805 may include structures 810 for improving the outcoupling (light extraction). By providing the structures 810 or surface structures on the area light source 805, the light extraction from the area light source 805 can be significantly improved, so that the reflective beam formers 800-1; 800-2 or the systems with the surface light source 805 can be optimized in terms of their energy efficiency. By optimizing the energy efficiency, the intensity of the radiation of the reflective beam shaper 800-1; 800-2 to be maximized. Furthermore, it is possible that by the combination of the surface light source 805 (with the structures 810 and the coupling-out structures) and the beam-forming planar structure 710-1; 710-2, an improved system can be created in which, on the one hand, increased energy efficiency and, on the other hand, simultaneously improved beam shaping for generating the desired emission characteristic can be achieved.

Fig. 9 shows a side view of a system 900 with two inventive reflective beam shaper 900-1; 900-2 for setting a radiation characteristic of a surface light source emitting on both sides, for example an OLED 905. The two reflective beamformers 900-1; 900-2 of the system 900 include, for example, the beam-forming laminar structure 710-1; 710-2 from Fig. 7a , b. As in Fig. 9 As shown, the system 900 includes the reflective beamformer 900-1 and the further reflective beamformer 900-2. The area light source 105 of Fig. 1 corresponding two-sided radiating surface light source (eg an OLED) 905 is arranged between the reflective beam shaper 900-1 and the further reflective beam shaper 900-2. Thus, the radiation characteristic of the two-sided radiating surface light source 905 can pass through the beam-forming planar structure 710-1 of the reflective beam shaper 900-1 and the beam-shaping areal structure 710-2 of the further reflective beamformer 900-2 can be adjusted. By way of example, in the case of a surface light source radiating on both sides, the desired emission characteristic can be generated in a first half space which adjoins a first side of the surface light source and in a second half space which adjoins a second side of the surface light source opposite the first side.

In further embodiments, with respect to Fig. 1 For example, the first side 112 of the beam-forming sheet-like structure 110 between the light-transmitting beam-forming openings 115 may have a diffractive or diffusive structure, so that an angular mixing of reflected light components is achieved, whereby an improvement of the light recycling can be achieved.

In further embodiments according to Fig. 1 the ratio between the lateral extent L1 of the transparent beam shaping openings 115 on the first side 112 of the beam-forming planar structure 110 and the lateral extent L2 of the transparent beam shaping openings 115 on the second side 114 of the beam-forming planar structure 110 is, for example, in a range of 1: 1, 4 to 1: 3.

In further embodiments, the in Fig. 1 Reflective beamformer 100 shown may be designed such that a ratio between the lateral extent L2 of the transparent beam-forming openings 115 on the second side 114 and the thickness D of the beam-forming planar structure 110 between the first side 112 and the second side 114, for example in a range of 1 : 1.5 to 1:10 lies.

By using the just mentioned exemplary parameter ranges for the reflective beam shaper, an optimized emission characteristic with a relatively large deflection of the center of gravity and a comparatively small half width of the angular distribution can be produced.

In further embodiments, the translucent beam-forming apertures 115 of the beam-forming sheet-like structure 110 may be filled with a transparent material, so that the stability of the reflective beam-former 100 can be significantly increased.

In further embodiments, a system may be implemented with the reflective beamformer 100, which further includes the area light source 105, and wherein the translucent beamforming apertures 115 of the beamforming areal structure 110 are filled with a transparent material, wherein the first side 112 of the beam-forming sheet-like structure 110 is adjacent to the surface light source 105. By directly contacting the surface light source 105 to the first side 112 of the beam-forming planar structure 110, the coupling-out efficiency of the surface light source 105 can be improved by taking into account the refractive index ratios in the transparent material of the transparent beam shaping openings 115 and in the area light source 105, the total internal reflection at the Interface of the surface light source 105 is avoided or at least partially suppressed.

gegeben. Hierbei sind X und Y die lateralen Ortskoordinaten, während Θ und Φ Polar- und Azimuthwinkel sind. Diese sind in dem Koordinatensystem 1003 von Fig. 10a beispielhaft dargestellt. Die Funktion B (X, Y, Θ, Φ, λ) bezeichnet beispielhaft eine beliebige orts-, winkel- und wellenlängenabhängige Abstrahlcharakteristik. λ ist die Wellenlänge. FIGS. 10a . b show schematic representations to illustrate a radiation characteristic of a reflective beam shaper according to the invention. In the schematic representation of Fig. 10a is shown by a surface element dA outgoing radiation. The emission characteristic or the emission profile is characterized by its dependence on locations, angles and the wavelength. The power dP emitted by the surface element dA of a luminous surface in the solid angle element dΩ is in the general case dependent on location, angle and wavelength and, for example, by $$\mathit{dP}=B\left(\mathrm{X}.\mathrm{Y}.\Theta .\Phi .\lambda \right)dA\mathrm{}\mathit{dw}$$

given. Here, X and Y are the lateral location coordinates, while Θ and Φ are polar and azimuth angles. These are in the coordinate system 1003 of Fig. 10a exemplified. The function B (X, Y, Θ , Φ , λ ) denotes by way of example any location, angle and wavelength-dependent emission characteristic. λ is the wavelength.

For example, the radiation characteristic of solid-state light sources, such as organic light-emitting diodes (OLED), regulated by internals of their internal structure. In this case, the emission generally takes place in the entire half space, wherein the emission profile typically by a Lambertian direction distribution with a surface normal (eg surface normal 1011 in Fig. 10a ) is characterized as the center. The spatial distribution of the radiation pattern usually varies little. However, with the reflective beamformer according to the invention, any desired or complex emission characteristic can be generated, as shown by way of example in FIG Fig. 10a . b is shown.

In the schematic representation of Fig. 10b For example, two polar diagrams 1001, 1002 are shown, with which the reflective beam shaper according to the invention (eg reflective beam shaper 100 according to FIG Fig. 1 ) generated radiation characteristic 1010, 1020 and the emission profile can be illustrated. The in the polar diagram 1001 of Fig. 10b shown radiation pattern 1010 is characterized by a limited angular distribution, which may be beneficial for many applications of the reflective beam shaper. In addition, the in the polar diagram 1002 of Fig. 10b shown radiating characteristic 1020 by a predetermined (relatively large) deflection of the center of gravity of the angular distribution excellent. This is advantageous in that the generated radiation characteristic is adjustable within wide limits or flexibly. Thus, according to the schematic representations of Fig. 10a . b a desired radiation characteristic of the reflective beam shaper are generated, wherein the generated radiation characteristic can be distinguished by a limited angular distribution and / or a deflection of the center of gravity of the angular distribution. This is particularly advantageous for many applications of reflective beam shapers, such as for setting arbitrarily directed emission profiles of surface light sources.

In summary, the basic approach of the present invention is to provide a purely reflective structure (eg, reflective beamformer 100 in FIG Fig. 1 ), in which the top and top surfaces (first and second sides 112, 114) are substantially parallel to the light-emitting surface of the planar light source (area light source 105).

Referring to Fig. 1 the base and the top surface and the first and second sides 112, 114 are characterized in that they have a plurality of translucent openings, which are also connected by reflective inner surfaces (reflective side walls 117) to transparent areas or translucent beam forming openings 115th form. At the in Fig. 1 In the embodiment shown, the inlet openings of the light-permeable areas lying on the side facing the light source are smaller than the outlet openings located on the side facing away from the light source. Furthermore, according to the embodiment of Fig. 2a the translucent areas or translucent beam shaping openings 115 at an angle α to the interface normal (normal 201 in FIG Fig. 2a ) be inclined. Thus, the radiation characteristic associated with a single translucent area can be determined by the ratio of the size of the entrance and exit openings, the thickness D of the reflecting structure (beam-forming areal structure 110) and the resulting length L = D / cos ( α) of the translucent area along the dotted line (dashed line 215) and the special shape of the contour of the Inner surfaces or by the shape of the individual transparent area can be determined.

The corresponding two-dimensional arrangement of transparent beam shaping openings (beam-forming planar structure 210) in FIG Fig. 2b represents a beam-forming element, with which the radiation characteristic areal light sources can be adjusted without that different functional levels must be technologically complex or highly precisely aligned in the beam-forming element.

In the following, fundamental considerations for the design or for the inventive concept and advantages of the embodiments described above are presented.

The theoretical limit for an achievable angle restriction of an individual light bundle results from the etendue attitude and leads to the special case of the "Compound Parabolic Concentrator". This is a rotationally symmetric structure, which results from the application of the so-called "edge-ray principle" according to Welford / Winston. The ratio of the openings determines the achievable angle restriction. This is a fundamental physical aspect with general validity.

For a given aperture ratio, the best transmission of the overall structure is achieved when the exit apertures (cross sections on the second side 114) of the individual translucent apertures (beam shaping apertures) cover as much of the overall structure as possible. For example, this can be done by the in Fig. 5a to 5c shown embodiments can be achieved. Advantageous embodiments of periodic or quasi-periodic arrays (first, second, and third arrays 510, 520, and 530) of the individual transmissive regions (translucent beamforming apertures 515, 525, 535) may be of hexagonal or square symmetry in round output apertures, while in elliptical symmetry Can be initial openings of rhombic symmetry ( Fig. 5a to 5c ). The specific shaping of the contour of the inner surfaces of the individual transparent region can be carried out according to the target position for the emission characteristic, whereby aspects of the manufacturability should be taken into account. In embodiments, suitable shapes of the intersection of the inner contour of the translucent region may be, for example, linear (conical), hyperbolic, parabolic or segmented, as well as without or with a tendency to normal to the surface, as shown in FIG Fig. 4a-h is shown by way of example. Further, in other embodiments, other suitable changes in the lateral extent or cross-section of the translucent beam shaping openings from the first to the second Side of the beam-forming planar structure or along the thickness direction can be used, ie that these changes are z-dependent.

In further embodiments, cuts transverse to the axis (third axis 103) or in Fig. 3a to 3f cross-sections shown to be round, elliptical, quadrangular or polygonal. In the plan view of the single translucent opening (top views of Fig. 3a to 3f ) some of the possibilities are shown. Due to the limited Flächenfüllfaktor, which can be realized with the input sides of the individual translucent openings on the side facing the light source side of the reflective structure or the beam-forming planar structure, only a portion of the rays is directly transmitted, while other rays reflected back towards the light source become. From there, they can be reflected back into the direction of the beam-shaping element (beam-forming planar structure) with the reflectivity inherent in the surface light source, so that efficient light recycling can be obtained.

In further exemplary embodiments, the surfaces of the reflective structure facing the light source may, for example, be concave or convexly curved for beam shaping. Thereby, an angular mixing of the reflected light component can be achieved, whereby an improvement of the light recycling can be achieved (see Fig. 7a, b ). Such advantageous angle mixtures can be achieved in other embodiments by scattering or defractive structures on the light source facing surfaces of the reflective beam shaper or on the first side 112.

In order to improve the light extraction from surface light sources, such as OLEDs, they can be provided with surface structures according to further embodiments (see Fig. 8a, b ). Furthermore, an embodiment which is advantageous in terms of energy efficiency for the beam shaping of area light sources can be achieved by the combination of area light sources with structures for improving the extraction (area light source 805) and reflective structures for beam shaping (beam-forming areal structure 710-1; 710-2) according to the invention it exemplifies in Fig. 8a, b is shown.

In area light sources, the lateral dimensions are typically very large in comparison to the thickness of the light source, the ratios of the lateral dimensions to the thickness usually being greater than 10: 1 and may even exceed 100: 1. In order to be able to obtain the advantage of the small thickness of the surface light sources, the reflective structure for beam shaping (beam-forming planar structure) can likewise be made thin. This is achieved, for example, by the fact that the size ratios of input and output Outlet openings of the individual transparent areas and the thickness of the reflective structure can be suitably scaled while maintaining the radiation characteristic. In embodiments, particularly advantageous ratios of the lateral dimensions of the inlet and outlet openings of the light-permeable areas are in the range of 1: 1.5 and 1: 4. Furthermore, in further exemplary embodiments, particularly advantageous ratios of the lateral dimensions of the exit-side openings and the lengths of the light-permeable areas are in the range from 1: 2 to 1: 5 or even higher. For example, a reflective beamformer according to the invention for producing a desired emission characteristic with a deflection or a deflection angle of 35 ° and a half-value width of the angular distribution of 30 ° has a thickness of 0.8 mm, a radius of the entrance-side opening of the translucent region of 80 μm and a Ratio of the lateral dimensions of the inlet and outlet openings of the transparent areas of 1: 2.

Reflective beamforming sheet structures according to the present invention in which the transmissive regions are hollow (i.e., not filled with a material) can be produced, for example, by embossing techniques. Problems in shaping or demoulding in inclined, light-permeable areas can be avoided, for example, by virtue of the fact that the direction of movement of the punch or die corresponds to the direction of inclination of the light-permeable structure. Other manufacturing methods such. As injection molding are also applicable, but the production techniques cited are not exhaustive list.

If the structures are produced in transparent materials, for example in thin plastic films, they must be coated in a reflective manner after shaping. This production step can be omitted if metal foils are directly structured. For example, sputtering methods with which reflective metal layers can be produced can be used for the coating. In addition to metallic coatings, it is likewise possible to use dielectric layers in order to design the overall reflection behavior of the interfaces of the reflective structure as a function of the wavelength and the angle of incidence.

In other embodiments of the reflective beamformer, the translucent beam forming ports may be filled with a transparent material, such as a polymer. By filling the open reflective structure, its strength can be positively influenced. In addition, smooth interfaces that can be made by filling the translucent openings are less susceptible to contamination and, moreover, easier to clean.

In further exemplary embodiments, the directivity can be influenced by the choice of the filling material via the refractive index, wherein further filling material-specific effects, such as, for example, a wavelength-dependent transmission, can be utilized.

In further embodiments, filled reflective beam shaper, such as by gluing, be brought into direct contact with the surface light source, so that the Auskoppeleffizienz from the surface light source thereby improves that depending on the refractive index ratios, the total internal reflection at the interface of the surface light source at least partially suppressed becomes. In the design of the radiation characteristic, the refraction of light occurring at the exit opening of the transparent area, which reduces the possibility of the angle restriction, should be taken into account.

In embodiments with strictly periodic arrangements of the light-transmissive areas, location-independent angular distributions can be realized on average. The emission characteristic of the surface light source corresponds to 1: 1 of the radiation characteristic of the individual translucent opening. In embodiments with varying parameters, such as with respect to the ratio of the lateral extent of the inlet and outlet openings of the transparent areas or their inclination, location-dependent radiation characteristics can be realized (see Fig. 6 ). For the design of the individual translucent openings are the same degrees of freedom as shown above.

According to further embodiments, for two-dimensional radiating surface light sources by two inventive reflective beam shaper, the light distribution in both directions of radiation can be adjusted, as in relation to Fig. 9 is described. In this case, the respective reflective beam shaper can have both identical and different designs (see Fig. 9 ).

The embodiments described above are merely illustrative of the principles of the present invention. It will be understood that modifications and variations of the arrangements and details described herein will be apparent to others of ordinary skill in the art. Therefore, it is intended that the invention be limited only by the scope of the appended claims, rather than by the specific details presented in the description and explanation of the embodiments herein.

Embodiments of the present invention provide a reflective beamformer for adjusting arbitrarily directed emission profiles of surface light sources. With the reflective beamformer according to the invention, the generation of a broadly adjustable radiation characteristic of a planar light source by a reflective overall structure, in which individual translucent and jet-forming openings are arranged periodically or variably, allows.

In contrast to the emission characteristics of solid-state light sources, such as organic light-emitting diodes (OLED), which is controlled by internals of the internal structure and usually in the whole half space occurs (usually with a Lambertian direction distribution with the surface normal as the center, the spatial distribution usually little varies), or as for example transparent OLED, in which the radiation can also be up and down, with the inventive reflective beam shaper, a special, differently directed radiation, which is desirable for many applications can be generated. For example, embodiments of the present invention allow limited angular distribution and / or deflection of the center of gravity of the angular distribution (see Fig. 10a . b ).

In general, embodiments of the present invention provide an improved way of adjusting the radiation characteristic of areal light sources.

Incidentally, embodiments of the present invention enable a largely free adjustability of the radiation characteristic of planar light sources, wherein a technologically complex or highly precise alignment of different functional levels (apertures, lenses, etc.) can be avoided in the manufacture of the beam shaper.

The present invention can be used primarily in lighting, as well as for all applications in which flat light sources with special emission characteristics must be used.

Claims (13)

1. A reflective beam shaper (100) for generating a desired radiation characteristic from a radiation characteristic of a planar light source (105), comprising:

   a beam-shaping planar structure (110) having a plurality of translucent beam-shaping openings (115) which extend from a first side (112) to be facing the planar light source (105) to a second side (114) opposite to the first side (112) through the beam-shaping planar structure (110);

   wherein the translucent beam-shaping openings (115) comprise reflective sidewalls (117); and

   wherein a lateral extension (L1) of the translucent beam-shaping openings (115) on the first side (112) of the beam-shaping planar structure (112) is smaller than a lateral extension (L2) of the translucent beam-shaping openings (115) on the second side (114) of the beam-shaping planar structure (110) so that the radiation characteristic of the planar light source (105) is altered to the desired radiation characteristic when passing through the beam-shaping planar structure (110),

   characterized in that:

   the beam-shaping planar structure (710-1; 710-2) is reflective on its first side (112).
2. The reflective beam shaper (200) in accordance with claim 1, wherein the translucent beam-shaping openings (115) of the beam-shaping planar structure (110) are tilted relative to a normal (201) of the beam-shaping planar structure (110) under a predetermined tilt angle (α).
3. The reflective beam shaper (100) in accordance with claims 1 or 2, wherein the translucent beam-shaping openings (310; 320; 330; 340; 350; 360) of the beam-shaping planar structure (110) comprise a first and second cross sections (312, 314; 322, 324; 332, 334; 342, 344; 352, 354; 362, 364) on the first and second sides thereof, respectively, which comprise a round, elliptical, quadrangular or polygonal shape and are arranged relative to each other to be congruent or incongruent and laterally offset from each other or centered.
4. The reflective beam shaper (100) in accordance with any of claims 1 to 3, wherein the lateral extension (S) of the translucent beam-shaping opening (410; 420; 430; 440; 450; 460; 470; 480) changes from the first to the second side (112, 114) in a linear, hyperbolic, parabolic or segmented manner.
5. The reflective beam shaper (100) in accordance with any of claims 1 to 4, wherein the translucent beam-shaping openings (515; 525; 535) of the beam-shaping planar structure (110) on the second side (114) thereof are arranged regularly next to one another, wherein the regular arrangement (510; 520; 530) is a hexagonal, squared or rhombic or triangular grid.
6. The reflective beam shaper (600) in accordance with any of claims 1 to 5, wherein, between neighboring translucent beam-shaping openings (615-1, 615-2), the ratio between the lateral extension (L1, L1') of the translucent beam-shaping openings (614-1, 615-2) on the first side (112) and the lateral extension (L2, L2') of the translucent beam-shaping openings on the second side (114) and/or the tilt angle (α, α') of the translucent beam-shaping openings (615-1, 615-2) change/s laterally.
7. The reflective beam shaper (700-2) in accordance with any of claims 1 to 6, wherein the first side (712) is curved in a convex or concave manner between the translucent beam-shaping openings (115).
8. The reflective beam shaper (100) in accordance with any of claims 1 to 7, wherein the first side (112) comprises a diffractive or scattering structure between the translucent beam-shaping openings (115).
9. The reflective beam shaper (100) in accordance with any of claims 1 to 8, wherein a ratio between the lateral extension (L1) of the translucent beam-shaping openings (115) on the first side (112) of the beam-shaping planar structure (110) and the lateral extension (L2) of the translucent beam-shaping openings (115) on the second side (114) of the beam-shaping planar structure (110) is in a range from 1:1.4 to 1:3.
10. The reflective beam shaper (100) in accordance with any of claims 1 to 9, wherein a ratio between the lateral extension (L2) of the translucent beam-shaping openings (115) on the second side (114) and a thickness (D) of the beam-shaping planar structure (110) between the first side (112) and the second side (114) is in a range from 1:1.5 to 1:10.
11. The reflective beam shaper (100) in accordance with any of claims 1 to 10, wherein the translucent beam-shaping openings (115) of the beam-shaping planar structure (110) are filled by a transparent material.
12. A system comprising a reflective beam shaper (100) in accordance with any of claims 1 to 11, further comprising the planar light source (105), wherein the translucent beam-shaping openings (115) of the beam-shaping planar structure (110) are filled by a transparent material, wherein the first side (112) of the beam-shaping planar structure (110) is adjacent to the planar light source (105).
13. A system (900) comprising a reflective beam shaper (900-1) in accordance with any of claims 1 to 12, further comprising a further reflective beam shaper (900-2) in accordance with any of claims 1 to 12, wherein the planar light source (905) is radiating to both sides and arranged between the reflective beam shaper (900-1) and the further reflective beam shaper (900-2) so that the radiation characteristic of the planar light source (905) radiating to both sides is adjusted when passing through the beam-shaping planar structure (710-1) of the reflective beam shaper (900-1) and the beam-shaping planar structure (710-2) of the further reflective beam shaper (900-2).

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