LIGHTING UNIT AND LUMINAIRE

Abstract

A lighting unit (100) for a medical luminaire (150) has a number of groups of LEDs (110, 110′, 110″) that are connected to a common planar printed circuit board (115). Each LED (112, 112′) of at least one of the groups (110, 110′) is associated with a respective optic (122, 122′) by which a respective LED-optic pair (120, 120′) is formed. The respective optics, based on the structure (328), specify a tilt angle (125) of a central light beam axis (124, 124′) of an emitted light beam of the LED optics pair in a tilt direction (627) of the respective LED optics pair. The tilt direction is defined such that the respective light beam axes of the emitted light beams of the LED optics pairs from the at least one group of LEDs are at least partially skewed in pairs with respect to one another.

Claims

1. A lighting unit for a medical light, the lighting unit comprising: a plurality of groups of LEDs; a common planar circuit board, the plurality of groups of LEDs being connected to the common planar circuit board; and associated optics, each LED of at least one group of said plurality of groups of LEDs being associated with respective associated optics to form a respective LED optic pair, wherein the respective associated optics comprises structure configured to predetermine a tilt angle of a central light beam axis of an emitted light beam of the respective LED optics pair into a tilt direction of the respective LED optics pair, and wherein the tilt direction of the respective associated optics is defined such that the respective light beam axes of emitted light beams of the LED optics pairs from the at least one group of LEDs are at least partially skewed relative to each other in pairs.

2. A lighting unit according to claim 1, wherein the central light beam axis of the LED optical pairs, which are skewed with respect to each other in pairs, each have different tilt directions in pairs to provide pair tilt directions.

3. A lighting unit according to claim 1, wherein the associated optics of each LED of the at least one group of LEDs comprise identically configured optics.

4. A lighting unit according to claim 1, wherein at least one LED from the at least one group of said plurality of groups of LEDs is associated with at least one further LED to form an LED cluster with the at least one further LED, wherein the LED cluster generates a common light beam with the respective central light beam axis.

5. A lighting unit according to claim 1, wherein the tilt direction of the respective associated optics is fixable to comprise an orientation about an orientation angle within a mounting plane of the respective LED in a direction of which the tilt angle of the pair of LED optics is oriented.

6. A lighting unit according to claim 1, further comprising a fastening mechanism associated with the optics, wherein the tilt direction is fixed via the fastening mechanism, and wherein the fastening mechanism permits secure fixing of the tilt direction via a discretely adjustable mounting of the optics via corresponding contact pins.

7. A lighting unit according to claim 1, further comprising a fastening mechanism associated with the optics, wherein the tilt direction is fixed via the fastening mechanism, and wherein the fastening mechanism comprises a rotatable mounting of the optics relative to the common printed circuit board.

8. A lighting unit according to claim 1, further comprising tilt direction adjustment means configured to adjust the tilt direction or an amount of the tilting angle or both adjust the tilt direction and an amount of the tilting angle of at least of the associated optics.

9. A luminaire comprising: a lighting unit, the lighting unit comprising: a plurality of groups of LEDs; a common planar circuit board, the plurality of groups of LEDs being connected to the common planar circuit board; and associated optics, each LED of at least one group of said plurality of groups of LEDs being associated with respective associated optics to form a respective LED optic pair, wherein the respective associated optics comprises structure configured to predetermine a tilt angle of a central light beam axis of an emitted light beam of the respective LED optics pair into a tilt direction of the respective LED optics pair, wherein the tilt direction of the respective associated optics is defined such that the respective light beam axes of emitted light beams of the LED optics pairs from the at least one group of LEDs are at least partially skewed relative to each other in pairs, and wherein the luminaire has a central luminaire axis, and wherein a light field of the luminaire is generated in a plane perpendicular to the luminaire axis at a light field distance from the luminaire by light comprising light from of the lighting unit.

10. A luminaire according to claim 9, wherein a plurality of central light beam axes of the LED optics pairs are formed at an angle to the luminaire axis.

11. A luminaire according to claim 9, further comprising a further lighting unit to provide a plurality of identical lighting units.

12. A luminaire according to claim 9, further comprising a further lighting unit to provide a plurality of lighting units arranged rotationally symmetrically with respect to the luminaire axis.

13. A luminaire according to claim 9, further comprising a further lighting unit to provide a plurality of lighting units, wherein the LED optical pairs of said further lighting unit are arranged on a planar circuit board different from said planar circuit board of said lighting unit.

14. A luminaire according to claim 13, wherein at least two different circuit boards of the lighting units of the luminaire are tilted with respect to each other by a board tilt angle.

15. A luminaire according to claim 9, further comprising at least two different optics that differ at least in the tilt angles defined by the respective optics.

16. A luminaire according to claim 9, wherein LED optical pairs equidistant from the luminaire axis have a respective light beam axis forming angles of substantially equal magnitude with a perpendicular line from a position of the respective LED to the luminaire axis.

17. A luminaire according to claim 9, further comprising a control unit configured to drive at least one subset of LEDs from the at least one group of LEDs separately from other LEDs from the corresponding group of LEDs outside said at least one subset.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In the drawings:

[0046] FIG. 1 is a schematic view of a first embodiment of a lighting unit according to the invention for a first embodiment of a luminaire according to a further aspect of the invention;

[0047] FIG. 2 is a cross-sectional view of various LED optical pairs of the first embodiment of the lighting unit according to the invention;

[0048] FIG. 3 is a cross-sectional view of an embodiment of a pair of LED optics, with one of different structures of an adjacent optic and with one of different attachment mechanisms;

[0049] FIG. 4 is a cross-sectional view of an embodiment of a pair of LED optics, with another of different structures of an adjacent optic and with one of different attachment mechanisms;

[0050] FIG. 5 is a cross-sectional view of an embodiment of a pair of LED optics, with another of different structures of an adjacent optic and with one of different attachment mechanisms;

[0051] FIG. 6 is a schematic view of a second embodiment of the lighting unit according to the invention for a second embodiment of the luminaire according to the further aspect of the invention;

[0052] FIG. 7 is a schematic view of light beam axes and a corresponding light field of the luminaire according to a further embodiment;

[0053] FIG. 8 is a schematic view of the tilt angle and tilt direction of two pairs of LED optics according to the invention;

[0054] FIG. 9 is a schematic view of a third embodiment of the lighting unit according to the invention for a third embodiment of the luminaire; and

[0055] FIG. 10 is a cross-sectional view through the luminaire according to the third embodiment of FIG. 9.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0056] Referring to the drawings, FIG. 1 shows a schematic representation of a first embodiment of a lighting unit 100 according to the invention for a first embodiment of a luminaire 150, in particular a medical luminaire 150, according to a further aspect of the invention.

[0057] The lighting units 100 comprise a number of groups of LEDs 110, 110′, 110″, namely three groups of LEDs in the present case. The LEDs of the group 110, 110′ have in the present case approximately the same distance from a central luminaire axis 160 of the luminaire 150, which intersects the display plane perpendicularly. The remaining LEDs form the third group 110″. Each of the groups of LEDs 110, 110′, 110″ is connected to and arranged entirely on a common planar circuit board 115 of the lighting units 100. In an alternative embodiment, the optical outputs of LEDs are at least partially arranged on a mounting plate that is at least connected to the printed circuit board 115, as shown for example in FIG. 4.

[0058] Each LED 112, 112′ from at least one group 110, 110′ from said number of groups is associated with a respective surrounding (adjacent interposed) optic 122, 122′ by which a respective LED optic pair 120, 120′ is formed. In the illustrated embodiment, each group of LEDs 112, 112′, 112″ from the number of groups of LEDs 110, 110′, 110″ has a respective surrounding optic 122, 122′, 122″. However, only the groups 110, 110′ according to the invention have LED optics pairs 120, 120′ in which the respective optics 122, 122′ have a tilt angle in one tilt direction due to their structure. This structure of the optics is described in the context of the following embodiment example.

[0059] Also shown in dashed lines in FIG. 1 are three areas of receptacles 155 into which further lighting units, such as a lighting unit identical in construction to the illustrated lighting units according to the invention, can be inserted. The receptacles 155 preferably have a connection area which ensures an electrical connection between a remaining part of the luminaire 150, such as a luminaire electronics in the luminaire housing, which is not shown, and the lighting units to be inserted. For this purpose, the lighting units also have an electrical connection that is not shown, so that an electronic system of the luminaire is connected to the LEDs 112, 112′, 112″ of the lighting units 100 via the printed circuit board 115. The insertion of the respective lighting unit into the corresponding receptacle 155 is preferably performed via a positive and/or non-positive connection, in particular via a snap-in mechanism. Alternatively or additionally, the fastening after an insertion can be carried out via screws, whereby a homogeneous contact to a base body and consequently a good heat flow can be provided in a particularly simple manner.

[0060] In the illustrated embodiment, the luminaire 150 is round, in particular circular, when viewed from below, i.e. from the illuminated area. In an embodiment not shown, the luminaire is elliptical or angular, in particular in the form of a regular n-gon. Particularly preferably, the luminaire is point-symmetrical with respect to the luminaire axis when viewed from below, for example flower-shaped, star-shaped or satellite-shaped.

[0061] The receptacles allow the luminaire 150 to comprise a plurality of identically configured lighting units. This plurality of lighting units can be arranged rotationally symmetrically with respect to the luminaire axis 160 in accordance with the receptacles 155.

[0062] According to the lighting units 100, each lighting unit would provide a separate dedicated printed circuit board 115 for electrically connecting the LEDs to the luminaire's electronics, which are not shown. Alternatively or additionally, the electronics or portions of the electronics for operating the LEDs may already be included on the corresponding planar circuit board. For example, LED drivers may be included on the printed circuit board. Preferably, only the electronics for a power supply and a control unit of the luminaire are outside the lighting unit.

[0063] By means of such a modular structure, different lighting units can be combined with each other. In addition, the modular structure can provide differently shaped luminaires according to the invention, such as luminaires with a different number and/or orientation of the lighting unit according to the invention.

[0064] FIG. 2 shows a cross-sectional view of various LED optical pairs 120, 120′, 120″ of the first embodiment of the lighting unit 100 according to the invention.

[0065] The respective surrounding optics 122, 122′, 122″ define a central light beam axis 124, 124′, 124″ of an emitted light beam of the corresponding LED optics pair 120, 120′, 120″ due to their shape. A light beam is formed by rays that extend essentially along the light beam axis and form a divergence angle with the light beam axis in the outer region of the light beam, which depends on the geometry of the optics used and on manufacturing tolerances. Here, the light beam axes 124″ of the third group of LEDs 112″ do not have a tilt angle, but are aligned along the surface normal on the mounting plane, which in the present case is aligned along the printed circuit board 115. The two central light beam axes 124, 124′ of the LED optic pairs 120, 120′ according to the invention have a tilt angle 125 against the surface normal of the mounting plane, which is the same for both LED optic pairs 120, 120′, but is oriented in different tilt directions. Thus, the light beam axis 124 of the LED optic pair 120 of the first group of LEDs 110 is oriented toward the center of the luminaire 150. In contrast, the light beam axes 124′ of the pair of LED optics 120′ of the second group of LEDs 110′ is oriented toward an edge region of the luminaire 150. Other orientations not shown between these two opposite tilt directions are possible according to the invention, as shown for example in FIG. 6. In this case, the light beam axes 124, 124′ do not run exactly in the plane of representation. The different tilt directions are selected in such a way that the light beam axes 124, 124′ have such different tilt directions into the display plane that both are skewed to each other, i.e. do not intersect along the straight line on which the respective light beam axes 124, 124′ lie.

[0066] In the embodiment shown, the respective surrounding optics 122, 122′, 122″ each have a lens-shaped central region which, together with the rest of the optics, forms a so-called TIR optic (Total Internal Reflection optic) which aligns the undirected emitted light of the respective LED into light beams along the corresponding light beam axes 124, 124′, 124″. Such a TIR optic comprises a central refractive region, formed for example by a lens, and a reflective edge region. Alternative embodiments are shown in FIGS. 4 and 5.

[0067] In addition to the tilt angle of the corresponding light beam axes 124, 124′, there is an angle of inclination 116 with respect to a plane perpendicular to the luminaire axis 160 by which the printed circuit board is tilted. In the illustrated embodiment example, this angle of inclination 116 is between 4° and 20°, in particular between 8° and 14°, preferably approximately 11°. The different tilt directions of the two optics 122, 122′ therefore result in two different tilting angles of the corresponding light beam axes with respect to the luminaire, which have an identical angular distance from the angle of inclination 116. Thus, according to the invention, by using the same optics but different tilt directions of the corresponding predetermined tilt angle, different tilt angles can be provided for the light field of the luminaire. By providing an additional angle of inclination 116 by which the printed circuit board is tilted, an angle band can be set accordingly by adjusting the tilt directions, which can vary between the angle of inclination minus the tilt angle of the corresponding optics and the angle of inclination plus the tilt angle of the corresponding optics. Thus, according to the invention, with only one optical component to be manufactured, namely an optic with a predetermined tilt angle, a multitude of possible tilt angles of the corresponding light beam axes with respect to the luminaire is made possible.

[0068] In addition to the tilting angle of the corresponding light bundle axes 124, 124′, there is an angle of inclination 116 relative to a plane perpendicular to the luminaire axis 160, about which the printed circuit board is tilted. In the exemplary embodiment shown, this angle of inclination 116 is between 4° and 20°, in particular between 8° and 14°, preferably approximately 11°. The different tilt directions of the two optics 122, 122′ therefore result in two different tilting angles of the corresponding light beam axes with respect to the lamp, which are at an identical angular distance from the angle of inclination 116. Thus, according to the invention, different tilt angles can be provided for the light field of the lamp by using the same optics but different tilt directions of the corresponding predetermined tilt angle. By providing an additional angle of inclination 116 by which the printed circuit board is tilted, an angle band can be adjusted by adjusting the directions of tilt, which can vary between the angle of inclination minus the tilt angle of the corresponding optics and the angle of inclination plus the tilt angle of the corresponding optics. Thus, according to the invention, with only one optical component to be produced, namely an optic with a predetermined tilt angle, a multiplicity of possible tilt angles of the corresponding light beam axes with respect to the lamp is made possible.

[0069] In other embodiments, at least two different optics are provided for the luminaire according to the invention, which differ at least in their tilt angle.

[0070] Various exemplary embodiments for mounting the corresponding optics to form the pair of LED optics according to the invention are shown in the following embodiments.

[0071] FIGS. 3, 4, and 5 show a cross-sectional view of a respective embodiment of a pair of LED optics 320, 420, 520 with various structures 328, 428, 528 of a surrounding optics 322, 422, 522 and with various attachment mechanisms 340, 440, 540.

[0072] FIG. 3 shows a TIR optics 322 with a tilting of a central lens-shaped area, as it is basically already shown in FIG. 2. For clarity, the optics are shown in cross-section, while the printed circuit board is shown in perspective. The angle by which the geometry of the optics is tilted correlates with the tilt angle provided by the optics, but is not necessarily identical to it. However, the attachment mechanism 340 for attaching the optic 322 to the circuit board 150 is additionally shown here. Thus, the optic 322 has at least two contact pins 342, preferably three contact pins, each of which can be inserted into one of the available slots 344 on the circuit board 115 to surround the LED 112 disposed on the circuit board 115. Providing at least three contact pins may further increase a resistance to rotation of the optics. By providing different slots 344, different tilt directions of the tilt angle of the optic 322 can be specified. Due to the discrete provision of slots 344, a discrete predetermined number of different tilt directions for the illustrated LED optic pair 320 can be defined, in particular can be defined during the manufacturing of the light fixture (luminaire). Alternatively, the intended tilt direction can already be taken into account during the manufacture of the printed circuit board, so that the slots corresponding to the intended location for the contact pins are provided only for this tilt direction. This avoids errors in the manual attachment of the optics during manufacture.

[0073] FIG. 4 shows an optical system 422 which, due to a mirror 423, preferably a parabolic mirror, an aspherical mirror and/or a free-form mirror, emits the light of the corresponding LED 112 along a predetermined light beam axis with a predetermined tilt angle. To provide a tilt angle, the mirror is preferably asymmetric.

[0074] The mirror 423 is attached to the mounting plate 417 via an attachment mechanism 440. In the present case, the mounting mechanism 440 comprises an annular part 442 with a groove 444 in which the corresponding optics can engage, so that a mounting is effected via an engagement of the optics 422 in the annular part 442. Alternatively, a commercially available LED optics socket may also result in attachment of the optics within the lighting unit according to the invention. Preferably, in the illustrated embodiment, the mounting mechanism 440 allows the optics to be rotatably mounted so that different tilt directions for the LED optics pair 420 can be continuously established.

[0075] In addition, FIG. 4 shows that the mounting plate 417 may be different from the circuit board 415. For example, in the illustrated embodiment, the LEDs 412 are arranged on the circuit board 415, and optical fibers 419 are used to direct the light to the corresponding optical output 470 on the mounting plate 417. In an embodiment not shown, the angle between the mounting plate and the circuit board is adjustable via a control unit of the light fixture (luminaire).

[0076] In this case, the LEDs 412 form an LED cluster that generates a common light beam with a light beam axis via the associated optics 422. Alternatively, the light of the LED cluster can be mixed in a single light guide. As is known, a light guide rod or the like can be used for this purpose.

[0077] FIG. 5 shows an optic 522 formed by a tilted lens with an asymmetric mount. The asymmetric mount is bonded to the printed circuit board so that the mounting mechanism 540 is formed over a planar bonded portion of the mount. In this regard, the optics 522 can be controlled by an adjustment unit 850 and thereby rotated upon receiving a corresponding signal. In the illustrated embodiment, the asymmetric mount is further adjustable via the adjustment unit 850. In this regard, the tilt of the lens can be changed. Rotation and tilting are performed mechanically via a motor, which is not shown and is controlled via the adjustment unit 580.

[0078] FIG. 6 shows a schematic representation of a second embodiment of the lighting units 600 according to the invention for a second embodiment of the luminaire 650 according to the further aspect of the invention, as viewed from the light field along the luminaire axis.

[0079] The lighting unit 600 differs from the lighting unit 100 of FIG. 1 in that more LEDs 612 are provided, and these LEDs can be controlled in groups via a central control unit 690 of the luminaire 650. Of the LEDs shown, at least two groups of LEDs 610, 610′ are provided in each of the three identically shown lighting units 600 with LED optical pairs 620, 620′ according to the invention. For clarity, the features of a respective lighting unit are shown for only one lighting unit 600. These have a tilt angle not shown in FIG. 6 and in each case a tilt direction 627 indicated by a respective arrow on the LED optics pair 620, 620′ in the illustration, which is different for the LED optics pairs even within a group of LEDs 610, 610′. The tilt direction 627 is here the direction within the mounting plane of a respective LED in which the tilt angle of this LED is aligned. This interaction of tilt angle and tilt direction has already been explained in the context of FIG. 2 and is shown in more detail in FIG. 8. In particular, the corresponding light beam axes of the respective LED-optic pairs, which are not shown, are formed at an angle to each other. In particular, the LED-optic pairs with an equal distance from the luminaire axis 160 have a respective light beam axis that forms a respective angle with a perpendicular line from the position of the respective LED to the luminaire axis with a substantially equal amount. This alignment also results in the amount of the angle of the perpendicular lines being substantially equal with the tilt directions. An exemplary arrangement of the light beam axes for a similar alignment of the tilt directions is shown in FIG. 7.

[0080] A handle 665 of the light 650 is also arranged in the area of the light axis 160, which is configured to adjust the position of the light 650 during use, for example in the operating room.

[0081] The control unit 690 is configured to control at least one subset 611 of LEDs from the at least one group of LEDs 610, 610′ from the at least one lighting unit 600 separately from other LEDs from the corresponding group of LEDs 610, 610′ outside of that subset 611.

[0082] Alternatively or additionally, the groups of LEDs 610, 610′ can also be controlled differently, whereby, for example, a light output, an intensity, a color, a color temperature or an on/off state of the correspondingly controlled subgroup 611 of LEDs can be changed via the control.

[0083] By such a group-wise control and/or by a control of subgroups of LEDs from a group of LEDs according to the invention, a particularly advantageous illumination of the light field by the luminaire according to the invention with the lighting unit according to the invention can be ensured, such as, for example, a preferred light field diameter, a preferred light field shape, a preferred color temperature of the light field, a preferred shading, a preferred radial intensity profile of the light and the like. Here, in particular, annular regions of homogeneous light intensity can be provided by the groups of LEDs 610, 610′ according to the invention.

[0084] Preferably, the tilt angles of the illustrated groups of LEDs are essentially the same. Alternatively, in addition to the selection of respective tilt directions, the groups of LEDs 610 and 610′ differ in the tilt angle, which is not shown. In the present case, the optics 622 of the group 610 differ from the optics 622′ of the other group 610′ in the respective tilt angle.

[0085] The lighting units 600, 600′ of the luminaire 650 are identically formed. In this regard, the circuit boards 615, 615′ of the lighting units 600, 600′ form separate circuit boards 615, 615′ that are tilted relative to one another by a board tilt angle that is not shown in the illustrated embodiment.

[0086] FIG. 7 shows a schematic representation of light beam axes 724 and a corresponding light field 775 of the lamp according to the invention, which is not shown, according to a further embodiment.

[0087] In the illustrated embodiment, the orientation of the tilt angles of the respective LED optics pairs 720, which is identical to luminaire axis 160, results in a saddle region 777 that is particularly narrow compared to the extent of the present luminaire.

[0088] The luminaire according to the invention can advantageously provide a large radiation intensity for the light field in a distance range around the light field distance 779. A point-like alignment of the light beam axes to a point would cause the intensity to drop sharply around this point. This effect can be avoided by the ring-shaped illumination shown. In this case, different groups of LED optics pairs can provide different annular areas of illumination, thereby advantageously providing a large area with a large intensity in the area of the light field compared to the light field edges. The light field distance 779 is advantageously between 80 cm and 1.30 m, in particular between 90 cm and 1.10 m, particularly preferably about 1 m. The light field 775 is preferably located at the saddle area 777 or in a neighborhood of the saddle area 777.

[0089] The orientation of the tilt directions 727 is similar to the orientation of the tilt directions 627 of the group of LEDs 610 of FIG. 6, namely such that LED optic pairs 720 having an equal distance from the luminaire axis 160 have a respective light beam axis 724 that forms a respective angle with a perpendicular line from the position of the respective LED to the luminaire axis 160 with a substantially equal amount. The annular region of illumination thus formed in the area of the light field 775 is substantially defined by the tilt directions 727 and the corresponding tilt angle of the substantially equal LED optical pairs 720.

[0090] In addition to the exemplary group of LEDs shown, other groups of LEDs may correspondingly result in other annularly illuminated areas in the vicinity of the light field 775. Here, a control unit preferably allows the respective group of LEDs and/or a respective subgroup of the group of LEDs to be controlled so that properties of the current illumination by the luminaire can be controlled, for example temporarily controlled.

[0091] FIG. 8 shows a schematic representation of tilt angle 825 and tilt direction 827, 827′ of two pairs of LED optics according to the invention. The explanations for this illustration are fundamental to the present invention and therefore apply analogously to all embodiments and embodiments.

[0092] The LEDs 812, 812′ are arranged on a printed circuit board 815 according to the invention. The optics of the two LED optics pairs shown are identical in construction and therefore have the same tilt angle 825. However, the two optics differ in their orientation and thus in their tilt directions 827, 827′.

[0093] Both LED optics pairs each emit a light beam with a light beam axis 824, 824′, which are skewed to each other and have angles in space have angles in space relative to the printed circuit board normal. These angles lying in space can be described in spherical coordinates. This is to explain the terms tilt direction and tilt angle in the sense of the present invention. For the description in spherical coordinates, the plane formed by the printed circuit board 815 is displaced parallel to the respective center of the light emission plane of the optics, which represents the equatorial plane, and the corresponding surface normal through the center of the LED 812, 812′ represents the polar axis for this purpose. The solid angles of the light beam axes 824, 824′ can then be described by an azimuth angle 884, 884′ (longitude) and a polar angle 888 (latitude). If both use the same optics, they therefore also have the same polar angle 888, i.e. in the sense of the invention the same tilt angle 825. Tilt angle 825 and polar angle 888 are therefore identical in the sense of the invention. This tilt angle 825 is a property of the optics. An additional degree of freedom results from a rotation of the optics about the polar axis, i.e. about the printed circuit board normal by the azimuth angle 884, 884′, which preferably has to be carried out during the mounting of the corresponding optics on the printed circuit board. If both optics have the same azimuth angle 884, 884′, then the light beam axes 824, 824′ run parallel. If the angle is different by 180°, then they intersect at a point in space and both light beam axes 824, 824′ are not skewed to each other. If the azimuth angles 884, 884′ are not different by 0° or 180°, then the light beam axes 824, 824′ are skewed with respect to each other. The azimuth angle 884, 884′ describes the tilt direction 827, 827′ in the sense of the invention. An embodiment of the present invention includes a lighting unit with at least one group of identical optics and therefore also with the same tilt angle 824, but at the same time with pairwise different tilt directions 827, 827′.

[0094] FIG. 9 shows a schematic diagram of a third embodiment of the lighting unit according to the invention for 900a third embodiment of the luminaire 950.

[0095] The lighting unit 900 is present in multiple identical configurations in the luminaire 950. The structure of the LED optics pairs 920, which each have different tilt directions 927 within the respective lighting unit, is not shown in detail for clarity. In addition to the LED optics pairs 920 with tilt direction 927, each lighting unit 700, has an LED optics pair without tilt angle 921 and thus also without tilt direction.

[0096] The lighting units 900 are arranged rotationally symmetrically to the luminaire axis 160.

[0097] From the cross-sectional view in FIG. 10, it can be seen what influence the change of the tilt direction 927 has on a radiation direction of the provided light beams.

[0098] In addition to the rotationally symmetrically arranged lighting units 900, the luminaire 950 has a central lighting unit 900′ that is at least partially annularly formed around the luminaire axis 160. The tilt angle 925′ of the LED optical pairs 920′ of the central lighting unit 900′ differs from the tilt angle 925 of the LED optical pairs 920 of the rotationally symmetrically arranged lighting units 900, as shown in FIG. 10. For the two light beams labeled with tilt angle 925, 925′, the corresponding tilt angle can be seen from FIG. 10, since the corresponding tilt direction 927 according to FIG. 9 is substantially parallel to the intersection line 980.

[0099] Finally, FIG. 10 also shows the arrangement of the LED optical pairs on a respective printed circuit board 915, 915′. Here, the printed circuit board 915 of the rotationally symmetrically arranged lighting unit 900 and the hard disk 915′ of the central lighting unit 900′ have a plate tilt angle 975 relative to each other. In addition, the advantageous direct connection between the circuit boards 915, 915′ and a base body 990 of the luminaire 950 is also shown in FIG. 10. The base body 990 serves as a heat sink of the luminaire 950, so that there is a heat flow from the LEDs to the base body 990. Advantageous materials for the configuration of the components of the luminaire 950 are known to the skilled person, so that they are not be discussed below.

[0100] Also shown here are the light beams of the various LED optics pairs and their different tilt angles and tilt directions. Even though it is not clear from FIGS. 9 and 10, some of the light beam axes shown are skewed in pairs so that they do not intersect in the space in front of the luminaire 950.

[0101] The structure of each optic may differ between different LED optic pairs.

[0102] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

LIST OF REFERENCE SIGNS

[0103] 100,600, 600′, 900, 900′ Lighting unit [0104] 110, 110′, 110″, 610, 610′ Group of LEDs [0105] 112, 112′, 112″, 412, 812 LED [0106] 812′ [0107] 115, 415, 615, 615′, 815, Printed circuit board [0108] 915, 915′ [0109] 116 Angle of inclination [0110] 120, 120′, 320, 420, 520, LED optics pair [0111] 620, 620′, 720, 920, 920′ [0112] 122, 122′, 122″, 322, 422, Optics [0113] 522, 622, 622′ [0114] 124, 124′, 124″, 724, 824 Light beam axis [0115] 824′, 924 [0116] 125, 825, 925, 925′ Tilt angle [0117] 150, 650, 950 Luminaire [0118] 155 Mounting for lighting unit [0119] 160 Luminaire axis [0120] 328, 428, 528 Optics structure [0121] 340, 440, 540 Attachment mechanism [0122] 342 Contact pin [0123] 344 Slot [0124] 417 Mounting plate [0125] 419 Glass fibers [0126] 423 Mirrored wall [0127] 442 Annular part [0128] 444 Groove [0129] 470 Optical output [0130] 580 Adjustment unit [0131] 627, 727, 827, 827′ 927 Tilt direction [0132] 611 Subgroup of LEDs [0133] 665 Handle [0134] 690 Control unit [0135] 775 Light field [0136] 777 Saddle area [0137] 779 Light field distance [0138] 884, 884′ Polar angle [0139] 888 Azimuth angle [0140] 921 LED optics pair without tilt angle [0141] 975 Plate tilt angle [0142] 980 Cutting line [0143] 990 Basic body of the lamp