EP2230448A1 - LED mirror cascade - Google Patents

Abstract

The light fixture (1) has point-shaped light sources (3) assigned for a reflector (5) that is allocated in a laminar arrangement. Another reflector (6) is spaced apart from the former reflector. The latter reflector is reflectively formed on the former reflector, and is provided with a light emitting punch hole (7). A hole center distance (a) of the reflectors is smaller than a distance (b) of the light sources. The light emitting punch hole includes number of holes that is bigger than the number of the light sources. The former reflector is provided with a beveling surface structure.

Description

The present invention relates to a surface-trained lamp with a plurality of point-shaped light sources, which are distributed in a planar arrangement associated with a reflector.

For zoned or complete illumination of rooms, surface-shaped luminaires have been proposed which have a large number of punctiform light sources, for example in the form of LEDs, which are distributed in a grid. Such flat trained lighting systems can be mounted for example on a wall, in particular on the ceiling of a room. Depending on the arrangement of the lamp but this may cause several problems. On the one hand, when a bright illumination of the room is desired and correspondingly high-intensity light sources are used, a dazzling of the room users occurs when they look obliquely upwards into the luminaire. Although a directed emission of the light downwards only with a very small opening angle would eliminate or greatly reduce the glare effect mentioned above, this would only illuminate a very small area of the room.

On the other hand, the atmospheric effect of previous flat design lighting systems is rather unsatisfactory. If the light sources hidden behind a ceiling panel in the manner of a "starry sky", there is virtually no more depth effect. In addition, the efficiency of the lighting system often suffers when the light sources are arranged behind a ceiling panel blinded.

On the other hand, if the light sources are arranged visibly in the ceiling, on the one hand the aforementioned glare effect occurs. On the other hand, even in the off state, the surface effect of the ceiling or its designability affected by the visible light sources.

The font DE 101 24 539 describes an LED light, which is not designed as a stationary light for the illumination of building spaces and squares, but as a motor vehicle tail light. The LEDs are arranged in recesses of a faceted reflector, wherein a pinhole is placed under the cover glass of the taillight in front of the bulb reflector assembly to produce the fashionable in motor vehicles phenomenon of a light source grid. However, the aforementioned pinhole is not reflective, so that it comes to relatively high radiation losses. In addition, the size of the perforation is intended to leave the bulbs behind the pinhole visible, which is not acceptable for stationary building lights due to the resulting glare.

The present invention has for its object to provide an improved luminaire of the type mentioned above, which avoids the disadvantages of the prior art and the latter develops in an advantageous manner. In particular, a wide distribution of light with a balanced ratio of vertical to horizontal illuminance with simultaneous depth effect of the visual appearance of the lamp should be achieved with a high degree of glare, without sacrificing good efficiency of the lamp.

According to the invention this object is achieved by a luminaire according to claim 1. Preferred embodiments of the invention are the subject of the dependent claims.

It is suggested that the punctiform light sources or the reflector associated therewith be pre-faded by a further, finely perforated reflector which reflects back part of the emitted light and allows another part of the light to pass through fine holes, so that a light point separation is achieved which eliminates glare phenomena , According to the invention, a second reflector is provided at a distance from said first reflector, which reflector is designed to be reflective on its surface facing the first reflector and is provided with a fine light emission perforation. By the mutually facing, reflective surfaces of the two reflectors a multiple reflection is achieved, which radiates the reflected light through the holes in the second reflector into the room. Thus, the majority of the light is blasted due to the high reflectance of the mirror surfaces in the room. The hole structure here is advantageously designed so that a transparency to the first reflector is created and the visual image, which cause the two reflectors in addition, creates a so-called dematerialized appearance. The lamp gets a depth effect, since the light seems to come from different levels. On the other hand, the light sources are in the off state behind the second, perforated reflector more or less invisible, so that the lamp is architecturally versatile and not disturb the ceiling or mural when switched off. The underside or the space-facing side of the second reflector can be designed as desired, for example, coated in color, printed with a pattern or provided with any other desired surface structure or design.

The Lichtaustrittslochung in the second reflector is hereby advantageously so finely formed that the image of the underlying point-shaped light sources and / or the light image generated by the first reflector is smashed so to speak. This smashing of the image of the light sources in a variety of points of light causes much less glare or completely eliminates glare. In addition, a suppression of the perforated plate material thickness with low stray light densities.

Advantageously, much more fine holes are provided in the said second reflector than are arranged behind the reflector light sources, i. the number of holes of Lichtaustrittslochung is significantly greater than the number of punctiform light sources. Here, the hole spacing of the perforation of the second reflector is advantageously much smaller than the distance of the light sources. Depending on the lighting task and the desired geometry of the luminaire, which may have a modular-small surface or can also be applied in the form of extended surfaces, the number of fine holes in the second reflector may be at least ten times as large, preferably more than one hundred times as large and in particular be more than a thousand times as large as the number of punctiform light sources. Depending on the hole diameter of the perforation, the hole spacing may be less than 1/3, preferably also less than 1/10 and in particular less than 1/30 of the distance of the point-shaped light sources from each other.

The holes of the Lichtaustrittslochung this advantageously have a hole diameter that is smaller than the diameter of the light sources, so that even when looking directly into the light not the entire light source can be seen as a single point. Depending on the diameter of the light source, the hole diameter of the reflector holes can be chosen differently, wherein advantageously the hole diameter is less than ½ times the diameter of the light source. If, for example, LEDs are used as punctiform light sources, a hole diameter of less than 2 mm can be provided in an advantageous embodiment of the invention, wherein advantageously the hole diameter is less than 1 mm. The diameter of the punctiform light sources may be between 2 and 5 mm in the case of using LEDs. However, not only LEDs can be used, but also other preferably punctiform light sources are used, for example halogen incandescent lamps.

In order to produce a plurality of mirror images and thereby give the lamp a great depth effect with balanced light distribution, the first reflector whose reflective surface facing the illuminated space, advantageously not flat, but with an embossing of the light reflective surface formed or an optically active surface structure provided. As a result, the light is reflected not only straight or the same direction on the second reflector or thrown through the perforation through, but there are differently directed reflections, which creates a variety of mirror images in conjunction with the transparency of the perforated second reflector.

The aforementioned surface structure of the reflective surface of the first reflector can in principle be designed differently. Advantageously, a faceted surface structure is provided which does not give rise to a milky-uniform mirror image, but rather gives rise to a multiplicity of discrete mirror images whose arrangement varies depending on the viewing angle of the luminaire. The facet-shaped embossing of the reflective surface of the first reflector makes the surface-shaped light in the manner of a diamond always sparkle differently when the viewer moves through the illuminated space.

In a further development of the invention, the surface structure of the first reflector may comprise a plurality of trough-shaped recesses, which are preferably distributed in a corresponding arrangement with the planar, distributed arrangement of the light sources. The recesses mentioned are advantageously formed facet-shaped, in particular pyramidal depressions may be provided. For such pyramidal surface structures fundamentally different bases may be provided, for example, the pyramids may have triangular, square, pentagonal or hexagonal bases, with a good compromise between a simple production on the one hand and a sufficiently high mirror multiplication by To achieve a pyramid structure of pyramids with a square plan.

The depressions of the surface structure in this case advantageously have a relatively large opening angle of preferably at least 2 x 45 ° in order to ensure a broad illumination. In a development of the invention, the depressions can have an opening angle in the range of 2 × 50 ° to 2 × 70 ° and preferably about 2 × 60 °.

The depth of said depressions of the surface structure is advantageously smaller than the diagonal over the upper edge of a trough-shaped depression or over the opening cross-section of the depression. For example, if square pyramids are embossed in the reflector, the pyramid depth or height may be less than 50% of the diagonal across the pyramid base.

The trough-shaped depressions of the faceted surface structure are advantageously subdivided into a plurality of distinguishable and delimited surface segments, wherein advantageously a subdivision into planar surface segments is provided, as is the case, for example, with diamond grinding.

The point-shaped light sources are advantageously arranged in the trough-shaped depressions of the surface structure, wherein the light sources are advantageously centered and / or positioned at the bottom of the respective recess.

In an advantageous embodiment of the invention, the point-shaped light sources may be arranged on a printed circuit board which extends behind the first reflector. Said first reflector advantageously has a multiplicity of through-openings, through which the point-shaped light sources are inserted from a rear side of the reflector into the trough-shaped recesses.

The second reflector, which has said light exit holes, advantageously has a different surface shape from the first reflector. According to an advantageous embodiment of the invention, said second reflector is planar and / or free of a surface structure.

Depending on the application, however, said second reflector may also be uneven. In particular, when an asymmetric light emission is desired, it may be advantageous if the second reflector is provided with an asymmetric surface structure and / or an asymmetric embossing. In particular, said second reflector may have an asymmetrical fold in which the holes of the light exit perforation are oriented all and / or in predominate numbers to one side, in particular in legs of the fold are directed, which are directed to the same side.

If said second reflector is provided with an asymmetrical surface structure, in an advantageous development of the invention the first reflector is also provided with an asymmetric embossing or surface structure, whereby advantageously the main direction of the surface structure of the first reflector is tilted towards the same side as the main axis of the surface structure of the second reflector. As a result, asymmetric radiation can be achieved with high efficiency.

For example, if the first reflector provided with a pyramidal embossing, the major axes of the pyramids are tilted at an acute angle of less than 90 ° to the plane of said first reflector. If the second reflector is provided with said oblique fold, the major axes of the fold, which divide a respective fold into two equal opening angles, are tilted towards the same side at an equally acute angle of less than 90 °.

Regardless of their surface structuring and embossing, the two reflectors are advantageously arranged in mutually parallel planes. By changing the distance of the two reflectors from each other can be easier Way the depth effect of the light can be controlled. In this case, a movable, in particular displaceable mounting of at least one of the reflectors can advantageously be provided. The distance variable mounting or mounting of the two reflectors allows a simple change of the depth effect and adaptation of the lamp to different installation situations.

Advantageously, the second reflector is flat or it may be formed in the form of a flat plate having said perforation. The first reflector is advantageously shaped in relief and provided with the aforementioned trough-like depressions, but in this case may have a flat envelope surface, i. the aforementioned recesses lie with their opening and / or bottom cross-sections in each case in a common plane. Advantageously, the light can be designed overall in the form of a flat panel, so that it can be fitted to the usual flat ceiling and wall contours in an advantageous manner as a wall and / or ceiling light. Advantageously, the light sources can also be arranged in a common plane. In an alternative embodiment of the invention, the lamp or the first and second reflectors may also have a preferably regular, continuous and continuous curvature, for example, to adapt to a barrel-shaped ceiling have a cylindrical, trough-shaped or paraboloidal curvature, which is also advantageously provided here to provide the first and second reflectors with corresponding arches and / or to arrange them in a substantially constant distance from one another over the surfaces. In an advantageous embodiment of the invention, however, the first reflector, the second reflector and the light sources are arranged in mutually parallel planes.

In order to achieve high efficiency, the reflective surfaces of the two reflectors are each formed highly reflective, which in the invention, a reflectance of at least 90%, preferably at least 95% and in particular 97% or more may be provided.

On the one hand to give the first reflector sufficient transparency, which gives rise to the desired depth effect, but on the other hand, to avoid a glare, the second reflector has a hole content of preferably 5% to 25%, i. 95% to 75% of the area of the reflector is formed by reflective material, while the hole area accounts for about 5% to 25% of the total area of the reflector. In a preferred embodiment of the invention, said hole proportion is 10% to 15%, whereby a good compromise between transparency and depth effect on the one hand and glare on the other hand is achieved.

Fig. 1:

eine perspektivische, schematische Darstellung einer flächig ausgebildeten Leuchte nach einer vorteilhaften Ausführung der Erfindung in einem Teilschnitt, der den gelochten Reflektor und eine darüber liegende Glasplatte teilweise weggeschnitten zeigt, um den darunter liegenden ersten Reflektor und die darauf angeordneten Lichtquellen zu zeigen,

Fig. 2:

eine Schnittansicht der Leuchte aus Fig. 1, die von oben nach unten übereinander die Abdeckscheibe, den gelochten zweiten Reflektor, den hiervon beabstandeten ersten Reflektor mit pyramidenförmiger Prägung und darauf angeordneten Lichtquellen, die die Lichtquellen tragende Platine sowie den Gehäuseboden zeigt,

Fig. 3:

eine Draufsicht auf den mit einer pyramidenförmigen Prägung versehenen ersten Reflektor,

Fig. 4:

eine schematische Darstellung des Strahlengangs zwischen den beiden Reflektoren, und

Fig. 5:

eine ausschnittsweise Schnittansicht ähnlich Fig. 4 einer Leuchte nach einer alternativen vorteilhaften Ausführung der Erfindung mit asymmetrisch geprägten Reflektoren, die den Strahlengang zwischen den beiden Reflektoren verdeutlicht.

The invention will be explained in more detail below with reference to a preferred embodiment and associated drawings. In the drawings show:

Fig. 1:

a perspective, schematic representation of a surface-shaped lamp according to an advantageous embodiment of the invention in a partial section showing the perforated reflector and an overlying glass plate partially cut away to show the underlying first reflector and the light sources arranged thereon

Fig. 2:

a sectional view of the lamp Fig. 1 comprising, from top to bottom, the cover plate, the perforated second reflector, the first pyramidal shaped reflector spaced therefrom and light sources disposed thereon, the board carrying the light sources and the housing bottom,

3:

a top view of the provided with a pyramidal embossing first reflector,

4:

a schematic representation of the beam path between the two reflectors, and

Fig. 5:

a fragmentary sectional view similar Fig. 4 a luminaire according to an alternative advantageous embodiment of the invention with asymmetrically embossed reflectors, which illustrates the beam path between the two reflectors.

The mirror cascade shown in the figures forms a lighting system that is flat and module-small area or can be applied to extended areas. The room can be zoned or evenly illuminated.

In the illustrated embodiment, the lamp 1 comprises a substantially cuboid, flat housing 2, which may be formed, for example, as a sheet metal or plastic box and receives in its interior the functional components of the lamp.

As Fig. 2 shows, at the bottom of the housing 2, a printed circuit board 4 is arranged, on which in a regular grid a plurality of point-shaped light sources 3 are arranged, which are formed in the illustrated embodiment as LEDs.

Above the said board 4 sits a first reflector 5, which has an optically active surface structure 13 in the form of an embossment, which consists in the illustrated embodiment of a plurality of pyramidal depressions 9, which are arranged in a regular grid, which the grid of light sources 3 corresponds. At the bottom of the pyramid-shaped recesses 9 5 Durchtrittsausnehmungen 14 are formed in the reflector, through which the point-shaped light sources 3 are inserted from the board 4 ago, so that said light sources 3 are centrally positioned at the bottom of said pyramidal recesses 9.

The surface of said first reflector 5 provided with said pyramidal or faceted surface structure 13 is highly reflective designed to minimize losses. For example, the reflector 5 may be formed of an aluminum sheet with a highly reflective coating of Miro-Silver with a reflectance of 97%.

In the illustrated embodiment, the pyramidal depressions 9 have a square plan, so that the depressions have the contour of a four-sided, uniform pyramid. As Fig. 2 shows, the depth t of the recesses 9 is significantly smaller than the dimension of the clear width w at the top of the pyramidal recesses 9. In the illustrated embodiment, the opening angle of the pyramidal recesses 9 is twice 60 °. The base surface of the pyramidal recesses 9 may vary in size. In the illustrated embodiment, it is on the order of 5 x 5 cm and 15 x 15 cm, wherein advantageously all depressions 9 have substantially the same geometry. The arrangement of the recesses 9 is made in a uniform grid. In the illustrated embodiment, the surface structure 13 in the form of the depressions 9 extends essentially over the entire surface of the reflector 5 or substantially over the entire base area of the luminaire 1.

Above the said first reflector 5 sits a second reflector 6, which is spaced from the first reflector 5 and is arranged in a plane parallel to the plane of the first reflector 5.

The first reflector 5 is in the illustrated embodiment according to Fig. 2 formed substantially planar and formed on its side facing the first reflector 5 side reflective. Also for the second reflector 6, a highly reflective surface is provided in order to achieve a high efficiency. The second reflector 6 can also consist, for example, of an aluminum sheet which is provided with a highly reflective surface coating made of Miro-Silver with a reflectance of 97%.

Said second reflector 6 is in this case provided with a fine Lichtaustrittslochung 7, which consists in the illustrated embodiment of a plurality of holes 8, which are arranged in a uniform grid, as Fig. 1 suggests. The said holes 8 are in this case of their diameter significantly smaller than the base surface of the recesses 9 of the surface structure 13 of the first reflector 5, and in particular also significantly smaller than the diameter of the punctiform light sources 3. In the illustrated embodiment, the diameter d of the holes. 8 the perforation 7 is less than 1 mm and is about 0.8 to 0.9 mm. The hole spacing a of the light exit holes 7 is also significantly smaller than the distance b of the point-shaped light sources 3, ie the grid of the light exit holes 7 is significantly finer than the grid of the light sources. 3

The spacing of the two reflectors 5 and 6 can be fundamentally different, with the depth effect of the luminaire can be changed by changing the distance between the two reflectors 5 and 6.

The side of the second reflector 6 facing away from the first reflector 5, i. the light exit side of the luminaire can be designed variably and does not have to be reflective. For example, the light exit side of the second reflector 6 may be colored coated to architecturally adapt the light to the desired interior design.

Above the second reflector 6 advantageously sits a transparent cover 15 to prevent dust from entering through the Lichtaustrittslochung 7 in the interior of the lamp. The cover 15 in this case advantageously includes flush with the housing 2.

Fig. 4 clarifies the by the light after the FIGS. 1 to 3 achievable beam path. The radiated from the point-shaped light sources 3 rays first meet the second reflector 6, wherein a part of the rays, which hit the holes 8 of the Lichtaustrittslochung 7, pass through the reflector 6, while the rest of the rays from the reflective surface of the second Reflectors 6 are thrown back. These reflected rays hit the first reflector 5 and are thrown back from the facetted surface structure 13 in different directions back to the second reflector 6, so that a multiple reflection is formed, so that the reflected light through the holes of the Lichtaustrittslochung 7 radiates into the room and a large part of the light is due to the high reflectance of the mirror surfaces in the room is blasted. Due to the fine perforation of the second reflector 6 in this case a light point separation is achieved, whereby glare phenomena are eliminated. At the same time, the perforated structure of the projected reflector plane gives transparency, by means of which the visual image is dematerialized and the luminaire acquires a depth effect. The guidance of the beam path achieves a light distribution with a very broad radiation characteristic and a balanced ratio of vertical to horizontal illuminance, without a dazzling effect occurring.

Fig. 5 shows an alternative embodiment of the lamp 1, in which the first reflector 5 and the second reflector 6 are provided with an asymmetric or to a side inclined surface structure, so that an asymmetric radiation image is obtained, which is perpendicular to the plane of the lamp 1 is inclined, cf. Fig. 5 , In this embodiment, therefore, the second reflector 6 is not flat, but also provided with an embossing or formed in relief.

In particular, the second reflector 6 in the illustrated embodiment Fig. 5 provided with a fold 10, which gives rise to a channel-shaped or corrugated sheet contouring of the second reflector 6, wherein the fold 10, however, so to speak here faceted, that is formed of flat surface portions with a Kantung between adjacent surface portions.

As Fig. 5 shows, in this case, the fold 10 is formed asymmetrically or inclined. A main axis 11 on the fold 10 is inclined at an acute angle to the reflector plane, wherein as the main axis 11, the entire opening angle centered halving straight line is meant, see. Fig. 5 ,

The first reflector 5 is similar to the previously described embodiment with a surface structure 13 comprising pyramidal recesses 9, but here the recesses 9 are contoured in the form of slanted pyramids, so that main axes 12, which divide the opening angle of the recesses 9 centrally, also acute angle to Reflective plane are inclined, see. Fig. 5 ,

As Fig. 5 shows, the longer portions of the fold 10 are aligned parallel to the flatter flanks of the recesses 9, while the shorter portions of the fold 10 are perpendicular thereto. This results in the in Fig. 5 illustrated beam path.

Claims (15)

Luminaire with a plurality of punctiform light sources (3), which are distributed in a planar arrangement associated with a reflector (5), characterized in that spaced from said first reflector (5), a second reflector (6) is provided at its The first reflector (5) associated surface is reflective and is provided with a fine Lichtaustrittslochung (7). Luminaire according to the preceding claim, wherein the Lichtaustrittslochung (7) of the second reflector (6) has a hole spacing (a) which is smaller than the distance (b) of the light sources (3), and / or has a number of holes, the substantially larger as the number of light sources (3). Luminaire according to the preceding claim, wherein the number of holes is at least ten times as large, preferably at least one hundred times as large, in particular at least a thousand times as large as the number of light sources (3). Luminaire according to one of the preceding claims, wherein the holes (8) of the Lichtaustrittslochung (7) have a hole diameter (d), which is smaller than the light source diameter and / or less than 2 mm, preferably less than 1 mm. Luminaire according to one of the preceding claims, wherein the light sources (3) are arranged in a preferably regular grid and / or the Lichtaustrittslochung (7) has a plurality of arranged in a preferably regular grid holes (8), wherein the grid spacing of the light sources (3 ) is three times, preferably at least ten times, in particular at least thirty times, the pitch of the Lichtaustrittslochung (7). Luminaire according to one of the preceding claims, wherein the second reflector has a hole surface portion in the range of 5% to 25%, preferably 10% to 15%, of the total area of the second reflector (6) and / or its perforated surface portion. Luminaire according to one of the preceding claims, wherein the reflectance of the reflective surface of the first and / or the second reflector (5; 6) is greater than 90%, preferably 95% and in particular 97% or more. Luminaire according to one of the preceding claims, wherein the first reflector (5) is provided with a preferably faceted surface structure. Luminaire according to the preceding claim, wherein the surface structure comprises a plurality of trough-shaped, in particular faceted recesses (9), which are preferably distributed in an arrangement corresponding to the distributed arrangement of the light sources (3). Luminaire according to one of the two preceding claims, wherein the surface structure consists of a plurality of pyramidal depressions. Luminaire according to one of the two preceding claims, wherein the depth t of the recesses (9) is smaller than the width or diagonal w of the upper recess edge contour, preferably 1/3 to 2/3 of said width w, and / or the recesses (9 ) have an opening angle in the range of 2 x 45 ° to 2 x 75 °. Luminaire according to one of the preceding claims, wherein the light sources (3) in the recesses (9), in particular at the bottom of the recesses (9) are arranged. Luminaire according to one of the preceding claims, wherein the two reflectors (5, 6) are arranged in mutually parallel planes, preferably at a distance from each other in the range of 25 mm to 300 mm, preferably about 50 to 150 mm. Luminaire according to one of the preceding claims, wherein the second and / or the first reflector (6; 5) is provided with an asymmetric surface structure. Luminaire according to the preceding claim, wherein the second reflector (6) is provided with an asymmetrical fold (10) whose main axis (11) is tilted towards the same side as a main axis (12) of the surface structure of the first reflector (5).

Images