DE102010045394A1 - lamp - Google Patents

Abstract

In at least one embodiment of the lamp (1), it comprises a heat sink plate (2) and a plurality of semiconductor light sources (3) which are attached to the heat sink plate (2) along at least one row (30). A row (30) defines a main direction of extension (x). Furthermore, the lamp comprises a reflector (4) with at least two partial reflectors (41, 42). In a cross section perpendicular to the main direction of extension (x), the partial reflectors (41, 42) are conical and each have a focal point (F) or a center point (M) as well as a focal length (f) or a radius (r). At least two elements from the group formed by the center point (M), the focal point (F) and the row (30) lie, viewed in cross section, within a circle (K) with a diameter (d) of at most 25% of the largest focal length (f) and / or the largest radius (r) of the partial reflectors (41, 42).

Description

A lamp is specified.

An object to be solved is to specify a luminaire which is adapted to generate an increased light intensity during operation.

According to at least one embodiment of the luminaire, this includes a heat sink plate. The heat sink plate may be or include a printed circuit board. In particular, the heat sink plate is made of a metal core board or consists of such. Preferably, the heat sink plate is flat and has two opposite, parallel aligned main sides and a main sides connecting end face.

According to at least one embodiment of the luminaire, this comprises a plurality of semiconductor light sources. The semiconductor light sources are mounted along one or more rows on the heat sink plate. In particular, the at least one row runs along a straight line. The semiconductor light sources are preferably light-emitting diodes, in short LEDs. For example, the semiconductor light sources are based on an inorganic semiconductor material such as GaN, InGaN, AlGaN, InAlGaN, GaP, AlInGaP, GaAs, GaAsP or InGaAs. An active zone of the semiconductor light sources may comprise one of said materials. The semiconductor light sources can emit light of essentially a single spectral color, for example green or red light, or else emit mixed-colored light, in particular white light.

In accordance with at least one embodiment of the luminaire, a main extension direction is predetermined by the row of semiconductor light sources. The luminaire has a greatest geometric extent, in particular along the main extension direction. The main extension direction preferably runs parallel to the at least one row of semiconductor light sources. If the luminaire has several rows, all rows can be oriented parallel to each other.

According to at least one embodiment of the luminaire, this comprises a reflector with at least two partial reflectors. The reflector is configured to reflect radiation emitted by the semiconductor light sources. The reflector is preferably formed of a reflective metal or has at least one metallic, reflective coating, for example with aluminum or with silver. The partial reflectors represent parts or partial areas of the reflector and have a different basic shape from each other.

According to at least one embodiment of the luminaire, the partial reflectors, in a cross section perpendicular to the main direction of extent and / or to the row of semiconductor light sources, are conically shaped or shaped like a conic. Cone-section-shaped can mean that the partial reflectors are each formed completely or in places, as seen in the cross-section, such as a circle, an ellipse, a parabola or a hyperbola. Furthermore, the partial reflectors each have at least one center or at least one focal point and at least one focal length or a radius.

According to at least one embodiment of the luminaire, at least two of the centers or foci or at least one of the centers and the foci and the row, seen in cross-section, are arranged one above the other or nearly one above the other. The series is punctiform in cross section. In particular, at least two elements are of the group, wherein the group is formed by at least one of the centers, at least one of the foci and at least one of the rows, as seen in the cross-section within a notional circle. A diameter of the circle is at most 25% of the largest focal length and / or 25% of the largest radius of the partial reflectors. Preferably, the circle within which at least two of the focal points, centers or rows are located has a diameter of at most 15% or at most 7.5% or at most 3% of the largest focal length or the largest radius. The luminaire can also have a plurality of such fictitious circles which do not overlap one another and within which at least two of the elements of said group are located.

In at least one embodiment of the luminaire, the luminaire comprises a heat sink plate and a plurality of semiconductor light sources which are attached to the heat sink plate along at least one row. Through the series a main extension direction is given. Furthermore, the luminaire comprises a reflector with at least two partial reflectors. In a cross section perpendicular to the main extension direction, the partial reflectors are each conical in shape and each have at least one focal point or at least one center and at least one focal length or at least one radius. At least two elements of the group formed by the at least one center point, the at least one focal point and the at least one row lie within a circle with a diameter of at most 25% of the largest focal length and / or of the largest radius of the partial reflectors.

For example, a collection of the radiation emitted by the semiconductor light sources can be realized by one of the partial reflectors. By the further partial reflector directional direction or focusing of the radiation can be accomplished. As a result, a light intensity of the lamp can be increased and / or maximized.

In accordance with at least one embodiment of the luminaire, the partial reflectors are uniformly shaped along the main extension direction. In other words, different cross sections of the partial reflectors are similar to each other, perpendicular to the main extension direction. The luminaire is formed along the main extension direction in particular rod-shaped or tubular with a constant or substantially constant cross section.

In particular, according to at least one embodiment of the luminaire, each of the partial reflectors is shaped, in particular, as a part, exactly one of the following geometric figures: circle, ellipse, parabola or hyperbola. With others. Words, each of the partial reflectors is preferably shaped like a part of exactly one of the said geometric figures. The partial reflectors, seen in the cross section, in particular not formed by a juxtaposition of different of said geometric figures.

According to at least one embodiment of the luminaire, at least one or exactly one of the partial reflectors, seen in the cross section, is formed as part of a circle or an ellipse. Alternatively or additionally, at least one or just one of the partial reflectors, as seen in cross-section, is shaped as part of a parabola or hyperbola.

In accordance with at least one embodiment of the luminaire, at most one row of the semiconductor light sources is attached to one of the main sides and / or to the front side of the heat sink plate. For example, each of the main sides is provided with exactly one row of the semiconductor light sources, or only the front side is equipped with a single row of the semiconductor light sources.

In accordance with at least one embodiment of the luminaire, a main emission direction of the semiconductor light sources is oriented transversely to a main emission direction of the luminaire. The main emission direction is in this case a direction along which the semiconductor light sources emit a maximum intensity during operation. In particular, the main emission direction is oriented perpendicular to an assembly plane of the semiconductor light sources on the heat sink plate. The fact that the main emission direction is oriented transversely to the main emission direction may mean that an angle between the main emission direction and the main emission direction is not equal to 0 ° and not equal to 180 °. In particular, the main emission direction is aligned perpendicular to the main emission direction.

In accordance with at least one embodiment of the luminaire, the partial reflectors are spaced apart from one another. In other words, the partial reflectors do not touch each other. For example, there is an air gap between the partial reflectors. The partial reflectors can be mechanically fixed relative to each other by a housing of the luminaire.

In accordance with at least one embodiment of the luminaire, a minimum distance between the row of semiconductor light sources and the partial reflectors is at least 50% of the smallest focal length and / or the smallest radius of the partial reflectors. The semiconductor light sources are thus not in the immediate vicinity of the partial reflectors. A positioning of the semiconductor light sources relative to the partial reflectors takes place in particular via the heat sink plate, so that the semiconductor light sources need not be attached directly to the partial reflectors.

According to at least one embodiment of the luminaire, a quotient of maximum focal length and / or radius and minimum focal length and / or radius of the partial reflectors is at most 3, preferably at most 2. The focal lengths and radii are therefore similar to one another.

In accordance with at least one embodiment of the luminaire, the at least one focal length and / or the at least one radius of the partial reflectors or are all focal lengths and radii between and including 5 mm and 125 mm, in particular between 10 mm and 75 mm inclusive.

In accordance with at least one embodiment of the luminaire, the heat sink plate, seen in the cross section, lies completely within the reflector or completely within an envelope of the reflector. The envelope is, for example, a closed fictitious line that has a minimum length and includes all of the partial reflectors seen in the cross-section.

According to at least one embodiment of the luminaire, a radiation component generated by the semiconductor light sources and leaving the luminaire without reflection at the partial reflectors is at most 30% or at most 20% and / or at least 5% or at least 10%. Likewise, it is possible that no or substantially no radiation leaves the luminaire without having been reflected at least once on the partial reflectors.

According to at least one embodiment of the luminaire, this has a plane of symmetry which is oriented parallel to the main emission direction. For example, the plane of symmetry is between two of the rows or one of the rows. The plane of symmetry preferably extends through the heat sink plate and may be oriented parallel to the main sides and / or perpendicular to the end face.

According to at least one embodiment of the luminaire, the luminaire is designed to emit a luminous intensity of at least 1000 cd or at least 2000 cd or at least 2500 cd along the main emission direction. The light emits the light generated, in particular within a small emission angle, for example less than 30 ° or less than 15 ° or less than 5 °. For example, the emission angle is the smallest contiguous angular range, as viewed in the cross-section, in which 50% of the light generated during operation is emitted. The light generated is therefore preferably concentrated on a small solid angle range, whereby the light intensity increases.

Such a lamp can be used, for example, as a spotlight. In particular, such a luminaire can be used for workplace lighting, for architectural lighting, for example in museums or in boutiques, or for targeted accent lighting of exhibits or partial areas of exhibition areas. In particular, the luminaire is adapted to illuminate comparatively small areas at a distance of, for example, at least 1 m or at least 2 m with a high illuminance of in particular more than 500 lx or more than 1000 lx.

In the following, a luminaire described here will be explained in more detail with reference to the drawing with reference to exemplary embodiments. The same reference numerals indicate the same elements in the individual figures. However, there are no scale relationships shown, but individual elements can be shown exaggerated for better understanding.

Show it:

1 and 3 to 6 schematic sectional views of exemplary embodiments of luminaires described here,

2 schematic three-dimensional representations of heat sink plates for luminaires described here, and

7 a schematic sectional view of a conventional lamp.

In 1 is a sectional view of an embodiment of a lamp 1 illustrated. The lamp 1 includes a heat sink plate 2 with two opposite, just shaped main sides 20 and with a front side 25 , The front side 25 is perpendicular to a main emission z of the lamp 1 oriented. The main pages 20 are aligned parallel to the main emission direction z. At the heat sink plate 2 For example, it is a metal core board.

At the front 25 is a plurality of semiconductor light sources 3 along a row 30 appropriate. The series 30 runs along a straight line perpendicular to the plane of the drawing 1 is oriented and forms an intersection with the drawing plane. The semiconductor light sources 3 have a main emission direction E, which is aligned parallel to the main emission direction z and in extension of the heat sink plate 2 runs. The semiconductor light sources 3 , which are preferably light-emitting diodes, that is to say spotlights, are designed to operate during operation of the luminaire 1 emit visible light.

Furthermore, the lamp includes 1 a reflector 4 with partial reflectors 41 . 42 , The partial reflector 41 , which symmetrically about a light exit opening L of the light 1 is arranged, seen in cross-section as a part of an ellipse shaped. The partial reflector 42 is conically shaped like a part of a parabola.

A first focus F1a as well as the row 30 lie, seen in the drawing plane, within a fictitious circle K1, drawn as a dash-dot line. A second focal point F1b of the partial reflector 41 and a focal point F2 of the parabolic subreflector 42 lie within the fictional circle K2. The circles K1, K2 each have a diameter d which is at most 25% of a minimum of the focal length f of the partial reflector 42 and a mean diameter of the subreflector 41 is. At the light 1 according to 1 are the foci F1b, F2 and the series 30 and the focal point F1a within the production tolerances exactly on top of each other.

A minimum distance D of the semiconductor light sources 3 to the partial reflectors 41 . 42 is greater than the focal length f of the subreflector 42 , The focal length f is smaller than the mean diameter of the partial reflector 41 , The result is the average diameter of the elliptical part of the reflector 41 as the arithmetic mean of the lengths of the semiaxes of the ellipse, after which the partial reflector 41 is shaped.

In 1 are exemplary some rays S of the semiconductor light sources 3 emitted light symbolized by arrow lines. Much of the of the semiconductor light sources 3 emitted light hits the partial reflector 41 , Because of the partial reflector 41 elliptical and is the series 30 the semiconductor light sources 3 at the focal point F1a, this radiation component becomes the focal point F1b of the subreflector 41 focused. Since this focal point F1b congruent with the focal point F2 of the subreflector 42 is located, this radiation component is parallelized and as a parallel beam or approximately parallel beam from the lamp 1 emitted through the light exit opening L therethrough.

A radiation component coming from the semiconductor light sources 3 without reflection on the reflector 4 directly from the lamp 1 is emitted out, is preferably less than 50% or less than 30%. The of the light 1 emitted radiation is relatively strongly directed. An emission angle is in particular in the range between 0 ° and 20 ° inclusive.

The partial reflectors 41 . 42 do not touch each other. The partial reflectors 41 . 42 are through a housing 5 , in 1 symbolized by a dash line, fixed relative to each other. The housing 5 can have reflective inner walls. Likewise, the main pages 20 the heatsink plate 2 be provided with a reflective coating. The heat sink plate 2 is completely in the reflector 4 and do not touch it, seen in the cross section.

In 2 are perspective views of embodiments of heat sink plates 2 illustrated. According to 2A are the semiconductor light sources 3r . 3b at the front 25 appropriate. The semiconductor light sources 3r . 3g are in an alternating sequence at the front 25 assembled. In the semiconductor light sources 3g these are, in particular, light-emitting diodes emitting in the blue spectral range and / or in the green spectral range, in the case of the semiconductor light sources 3r preferably by emitting in the red and / or yellow and / or orange spectral light emitting diodes. A color mixture of the semiconductor light sources 3g . 3r emitted radiation is found in particular by reflection at the reflector 4 instead of.

The semiconductor light sources 3r . 3g are in the only row 30 arranged. The main pages 20 are free from the semiconductor light sources 3g . 3r , A distance of adjacent semiconductor light sources 3g . 3r in the linear series 30 is preferably between 5 mm and 60 mm inclusive, in particular between 15 mm and 45 mm inclusive. An average electrical power consumption of the semiconductor light sources 3g . 3r is preferably between 50 mW and 3 W, in particular between 0.1 W and 1.5 W, approximately at approximately 1 W. Electrical tracks for contacting the semiconductor light sources 3r . 3g are not drawn in the figures.

Geometric dimensions of the heat sink plate 2 , which is rectangular in plan view, are along the x-direction, parallel to the row 30 For example, between 10 cm and 100 cm, in particular by 40 cm. An extension along the z-direction is, for example, between 2 cm and 30 cm inclusive, in particular between 3 cm and 15 cm inclusive. A thickness of the heat sink plate 2 is in particular between 1.5 mm and 10 mm inclusive, preferably between 1.5 mm and 5 mm inclusive. The number of semiconductor light sources 3r . 3g in line 30 is in 2 shown only schematically. For example, the number of semiconductor light sources 3r . 3g in line 30 in total between 5 and 60 inclusive, preferably between 12 and 30 inclusive.

According to 2 B is each a row 30 the semiconductor light sources 3 on each one of the main pages 20 the heatsink plate 2 attached, parallel to and close to the front 25 , Close to the front 25 may mean that the ranks 30 not more than 8 mm or not more than 3 mm from the front 25 are removed. The main emission directions E of the semiconductor light sources 3 are perpendicular to the main pages 20 oriented. In the semiconductor light sources 3 it can be as per 2A to act a sequence in different spectral regions emitting semiconductor light sources. It is also possible that all or part of the semiconductor light sources 3 emit white light. Further details of the heat sink plate 2 and the semiconductor light sources 3 can be related as with 2A be described described.

The in the 2A . 2 B described heatsink plates 2 can in all embodiments of the lamp 1 be used. For example, the heat sink plate finds 2 according to 2A Application in the embodiment according to 1 and the heat sink plate 2 according to 2 B in the embodiment of the lamp 1 according to 3 ,

In 3 is another embodiment of the lamp 1 illustrated. The heat sink plate 2 is oriented parallel to the main emission direction z. The partial reflector 41 is formed as part of a circle with the center M1. The partial reflector 42 is shaped as part of a parabola with focal point F2. The center M1 and the focal point F2 are congruent to each other and in front of the front side 25 the heatsink plate 2 , in the direction along the main emission z. The main emission directions E of the semiconductor light sources 3 that in the two rows 30 are arranged are aligned perpendicular to the main emission z.

One in z-direction from the semiconductor light sources 3 emitted radiation S1 impinges directly on the partial reflector 42 and is emitted approximately parallel to the main emission direction z. A radiation S2, which is emitted in the opposite direction to the z direction, first strikes the partial reflector 41 , is then reflected in the direction of the focal point F2 and subsequently through the partial reflector 42 also emitted approximately parallel to the main emission direction z. The partial reflector 41 So it serves to collect light, so that almost the entire radiation of the semiconductor light sources 3 either directly on the parallelizing sub-reflector 42 meets or through the subreflector 41 collected and concentrated in the direction of the focal point F2 and subsequently also through the partial reflector 42 is parallelized.

In the semiconductor light sources 3 they may be Lambertian radiators or approximately such radiators. As a result, only a small proportion of radiation from the semiconductor light sources 3 directly, without reflection on the reflector 4 , from the light 1 emitted.

Also in the embodiment according to the 4A . 4B are the rows 30 the semiconductor light sources 3 near the center M1 and the focal point F2, within the circle K. The partial reflector 41 is semicircular and the partial reflector 42 in the form of a parabola part. Again the partial reflector serves 41 to a light collection and light concentration in the focal point F2 of the parabolic subreflector 42 which is arranged for a parallelization of the radiation, see the rays S1, S2. The partial reflectors 41 . 42 are constantly merging.

According to 4A is the heat sink plate 2 with the semiconductor light sources 3 aligned parallel to the main emission z. In 4B is the heat sink plate 2 oriented obliquely to the main emission direction z. As well in 4A as well as in 4B is the heat sink plate 2 each radially with respect to the center point M1 and the subreflector 41 aligned. Due to the orientation of the heat sink plate 2 with the rows 30 the semiconductor light sources 3 can be the size of the radiation component, without reflection on the reflector 4 from the light 1 is emitted, change.

Relative to the center M1 of the subreflector 41 or on a puncture point of the series 30 through the plane of the drawing are the semiconductor light sources 3 in an angular range of at least 225 ° or at least 270 ° from the reflector 4 surrounded in the cross-section all around, so that only a comparatively small proportion of radiation without reflection on the reflector 4 the lamp 1 leaves. In embodiments according to the 5 This angle range is even greater and is at least 315 °, for example at about 335 °. The emission angle of the luminaire 1 can therefore be particularly small.

In 5 is the partial reflector 42 shaped like a part of an ellipse, the partial reflector 41 is circular. A predominant proportion of radiation coming from the semiconductor light sources 3 is emitted in the z-direction is from the partial reflector 41 concentrated in the focal point F2a. As a result, a predominant proportion of radiation passes through reflection at the partial reflector 42 in the second focal point F2b of the partial reflector 42 , Because the radiation is the lamp 1 Leaving F2b predominantly through the focal point is the light 1 Approximately viewable as a point light source or as a line light source. The partial reflectors 41 . 42 collide and form a kink. The partial reflectors 41 . 42 can be formed from a common, continuous sheet metal.

In 6 is another embodiment of the lamp 1 illustrated. The reflector 4 has three partial reflectors 41 . 42 . 43 on. The partial reflector 41 is shaped as part of a circle, the partial reflector 42 as part of an ellipse and the partial reflector 43 as part of a parable. The reflector 4 is shaped such that none of the semiconductor light sources 3 generated radiation immediately without reflection on the reflector 4 the lamp 1 can leave, compare the dash-dot line.

The of the semiconductor light sources 3 generated radiation arises according to 6 near the focal point F2a of the subreflector 42 and is from the circular partial reflector 41 additionally concentrated in the focal point F2a. The center M1 of the subreflector 41 as well as the focal point F2a are congruent one above the other within the manufacturing tolerances. The approximately the focal point F2a passing radiation is in the focal point F2b of the subreflector 42 directed. The focal point F2b is congruent with the focal point F3 of the parabolic subreflector 43 , Through the light 1 an approximately parallel beam is emitted along the main emission direction z.

The partial reflectors 41 . 42 . 43 go according to 6 kink-free into each other. A boundary between the partial reflectors 42 . 43 is in 6 symbolized by a small line. It can be the partial reflectors 41 . 42 . 43 overall formed in one piece or composed of several workpieces.

In 7 a conventional lamp is illustrated. Much of the from the semiconductor light source 3 emitted radiation leaves the lamp without reflection on the reflector 4 , The reflector 4 is in direct contact with the semiconductor light source 3 and to the heatsink plate 2 near the semiconductor light source 3 , The semiconductor light source 3 is not near a focal point or center of the reflector. An emission angle of the luminaire according to 7 is comparatively large and lies in the range between approximately 60 ° and 80 °. A light intensity of the luminaire according to 7 is therefore relatively low, the lamp is only partially used as a directional spotlight.

The invention described here is not limited by the description based on the embodiments. Rather, the invention encompasses any novel feature as well as any combination of features, including in particular any combination of features in the claims, even if this feature or combination itself is not explicitly stated in the patent claims or exemplary embodiments.

Claims (14)

Lamp ( 1 ) with - a heat sink plate ( 2 ), - a plurality of semiconductor light sources ( 3 ) along at least one row ( 30 ) on the heat sink plate ( 2 ), whereby through the row ( 30 ) a main extension direction (x) is given, and - a reflector ( 4 ) with at least two partial reflectors ( 41 . 42 ), where - the partial reflectors ( 41 . 42 ) in a cross-section perpendicular to the main extension direction (x) are conically shaped and each have at least one focal point (F) or a center (M) and a focal length (f) or a radius (r), and - at least two elements from the group characterized by the at least one center point (M), the at least one focal point (F) and the at least one row (M) 30 ), as seen in the cross-section within a circle (K) having a diameter (d) of at most 25% of the largest focal length (f) and / or the largest radius (r) of the partial reflectors ( 41 . 42 ) lie. Lamp ( 1 ) according to the preceding claim, in which the partial reflectors ( 41 . 42 ), seen in the cross-section, are at least partially shaped like at least one of the following listed geometric figures: circle, ellipse, parabola, hyperbola. Lamp ( 1 ) according to the preceding claim, in which the partial reflectors ( 41 . 42 ) are each formed as a part exactly one of the listed geometric figures. Lamp ( 1 ) according to one of the preceding claims, wherein at least one or exactly one of the partial reflectors ( 41 . 42 ), seen in the cross section, is formed as part of a circle or an ellipse, and at least one or exactly one of the partial reflectors ( 41 . 42 ), seen in the cross-section, is formed as part of a parabola or hyperbola. Lamp ( 1 ) according to one of the preceding claims, wherein on each of a main page ( 20 ) and / or an end face ( 25 ) of the heat sink plate ( 2 ) at most one row ( 30 ) of the semiconductor light sources ( 3 ) is attached. Lamp ( 1 ) according to one of the preceding claims, in which at least one of the main pages ( 20 ) of the heat sink plate ( 2 ) parallel to a main emission direction (z) of the luminaire ( 1 ) is oriented. Lamp ( 1 ) according to one of the preceding claims, in which a main emission direction (E) of the semiconductor light sources ( 3 ) transverse to the main emission direction (z) of the luminaire ( 1 ) is oriented. Lamp ( 1 ) according to one of the preceding claims, in which the partial reflectors ( 41 . 42 ) are spaced from each other. Lamp ( 1 ) according to one of the preceding claims, wherein, viewed in cross section, a minimum distance (D) between the row ( 30 ) of the semiconductor light sources ( 3 ) and the partial reflectors ( 41 . 42 ) at least 50% of the smallest focal length (f) and / or the smallest radius (r) of the partial reflectors ( 41 . 42 ) is. Lamp ( 1 ) according to one of the preceding claims, in which the at least one focal length (f) and / or the at least one radius (r) of the partial reflectors ( 41 . 42 ) between 5 mm and 125 mm inclusive. Lamp ( 1 ) according to one of the preceding claims, in which, seen in the cross section, the semiconductor light sources ( 3 ) in an angular range of at least 225 ° from the partial reflectors ( 41 . 42 ), starting from the row ( 30 ). Lamp ( 1 ) according to one of the preceding claims, in which the heat sink plate ( 2 ), seen in the cross section, completely within the reflector ( 4 ) or completely within an envelope of the reflector ( 4 ) lies. Lamp ( 1 ) according to one of the preceding claims, in which one of the semiconductor light sources ( 3 ) generated radiation component, the lamp ( 1 ) without reflection on the partial reflectors ( 41 . 42 ), does not exceed 30%. Lamp ( 1 ) according to one of the preceding claims, which is adapted to emit a light intensity of at least 1000 cd.

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