Lighting units and lamps

Abstract

The invention relates to a lighting unit (100) for a medical lamp (150) having a plurality of LED groups (110, 110', 110'), wherein the plurality of LED groups are connected to a common planar circuit board (115), wherein each LED (112, 112') in at least one group (110, 110') from the plurality of groups is assigned a corresponding surrounding optical device (122, 122'), by which a corresponding LED-optical device pair (120, 120') is formed. In this case, the corresponding optical device specifies, based on its structure (328), an inclination angle (125) of a central beam axis (124, 124') of the radiation beam of the LED-optical device pair toward an inclination direction (627) of the corresponding LED-optical device pair, wherein the inclination direction of the corresponding optical device is specified such that the corresponding beam axes of the radiation beams from the LED-optical device pairs of at least one group of LEDs are at least partially tilted in pairs relative to one another.

Description

Technical Field

[0001] The present invention relates to a lighting unit for a medical lamp having a plurality of LED groups. The present invention also relates to a lamp, in particular a medical lamp, comprising at least one lighting unit according to the present invention. Background Art

[0002] It is known to equip medical lamps with multiple LEDs, which are arranged on a base body of the lamp via a circuit board. Heat is conducted away from the LEDs via the base body. Using LEDs as a light source allows, for example, lamp color adjustment and minimal heat generation. Furthermore, LEDs generally have high power efficiency, require only low voltage, are dimmable, and allow for a small light source size. Finally, LEDs can be easily arranged on circuit boards, making them very robust for typical applications.

[0003] Regarding the orientation of such LEDs, it is known that the light of the respective LED is influenced, for example, collected, focused, and / or collimated, by an optical element assigned to the LED, and that the orientation of the optical element is determined by the orientation of the associated circuit board on which the LED is located. As is known, the circuit boards are located on corresponding substrates in order to dissipate the corresponding heat.

[0004] For example, DE 10 2011 008 474 B4 describes a surgical lamp in which the LEDs are aligned along a circuit board that is bent several times using a form fit to ensure particularly favorable illumination in the lamp's light field, which in medical environments is typically approximately 1 m away from the lamp. Summary of the Invention

[0005] The object of the present invention is to provide a particularly advantageous lighting unit for a correspondingly advantageously designed lamp, in particular a lamp having a lighting unit that can be produced particularly simply and cost-effectively.

[0006] In order to achieve this object, the present invention proposes a lighting unit for a medical lamp having a plurality of LED groups.

[0007] The plurality of LED groups are connected to a common planar circuit board, wherein each LED from at least one of the plurality of groups is assigned a corresponding surrounding optical system, with the optical system forming a corresponding LED-optics pair. The corresponding optical system, based on its structure, specifies an inclination angle of a central beam axis of a radiation beam of the LED-optics pair toward a tilt direction of the corresponding LED-optics pair, wherein the tilt direction of the corresponding optical system is specified such that the corresponding beam axes of the radiation beams of the LED-optics pairs from the at least one LED group are at least partially, and in particular, completely, tilted in pairs relative to one another.

[0008] The present invention recognizes that by providing suitable optical components, any desired course of the beam axis of an LED-optics pair can be specified for optimal illumination of the light field of the lamp. For this purpose, the optical components have a tilt angle and a tilt direction with a corresponding tilt angle of the central beam axis. This allows for a particularly variable illumination that can be adjusted to predetermined characteristics within the corresponding light field distance in front of the lamp, even with a small number of different optical components.

[0009] For the purposes of the present invention, an inclination angle is an angle that is not equal to 0°. Thus, even taking into account possible manufacturing tolerances, the inclination angle is an angle of at least 0.1°.

[0010] According to the present invention, a lighting unit is a module for a lamp in which all LEDs are connected to a common circuit board. These LEDs form a plurality of LED groups, wherein at least for one of these LED groups, an LED-optics pair according to the present invention is formed, which has the characteristics of the corresponding optical system according to the present invention. At least one of the plurality of LED groups includes a plurality of LEDs. For these corresponding plurality of LED-optics pairs, the corresponding beam axes are at least partially, and in particular all, offset in pairs relative to one another.

[0011] In the context of the present invention, “skewed” means that the beam axes do not intersect in space and are not parallel to one another, even taking into account possible production tolerances.

[0012] As is known, LEDs emit light at a solid angle of up to 180°, so arranging the optical system results in a radiation beam oriented around a central beam axis of the beam. With the beam axes offset relative to one another, the illumination of the light field can be adjusted particularly variably. For example, the light field diameter and illumination depth can be adjusted by the orientation of the optical system, and the light distribution within the light field can be tailored to the desired pattern.

[0013] In addition to the tilt angle caused by the corresponding optical system, an additional tilt of the beam axis can be achieved, for example, by tilting the corresponding circuit board relative to the lamp axis provided in the corresponding lamp. In addition to the circuit board, a mounting plate can also be provided for arranging a light conductor connected to the corresponding LED. In this case, the surrounding optical system is always arranged within the optical output of the LED, which, if a light conductor is used, can be spaced apart from the LED and, therefore, from the corresponding circuit board. In addition to the circuit board connected to the LED, such a mounting plate can form an additional mounting surface for the LED.

[0014] Other LEDs not belonging to the at least one LED group can, for example, be designed as surrounding optics or with optics without a corresponding tilt angle. Thus, the present invention teaches that at least some LEDs, namely LEDs from at least one LED group, can be influenced particularly easily with respect to their beam axes by a corresponding design of the surrounding optics, such that the tilt angles and tilt directions result in mutually skewed orientations in pairs. This advantageously makes it possible to provide a particularly individually customizable light field, in particular to deflect light where it contributes as best as possible to the desired light design and overall light field.

[0015] Furthermore, the simple provision of the tilt angle can result in the avoidance of complicatedly produced bending and / or multiple bending of the printed circuit board for tilting the light beam, as is known from the prior art.

[0016] The use of a flat circuit board offers the particular advantage of being able to conduct heat away from the LEDs in a particularly efficient and simple manner. This is necessary because LEDs generate heat due to a lack of radiant heat. Therefore, a corresponding thermal bridge can be created particularly easily by the base body resting against the flat circuit board. Furthermore, avoiding curved and / or multi-bent circuit boards results in a more robust design of the electronics and, therefore, a longer service life of the lighting unit. Finally, flat circuit boards are simpler and more cost-effective to manufacture than curved or multi-bent circuit boards.

[0017] The structure of the corresponding optical device that specifies the tilt angle and tilt direction includes at least one optical element, such as a lens and / or a reflector, such that the tilt angle relative to the beam axis is not equal to 0°. This can be achieved by an asymmetrical structure of the optical device, particularly the optical element. Alternatively or additionally, this can be achieved by tilting the optical element relative to the normal direction of the circuit board and / or the mounting plate of the corresponding LED. Alternatively or additionally, this can be achieved by a diffraction structure, such as a diffraction grating, a prismatic structure, free-form optics, reflector optics, a gradient lens, or a Fresnel lens. An offset between the focal point of the corresponding LED and the optical device, or a combination of refractive, diffractive, reflective, nanostructured, and / or microstructured optics, can also be provided. Particularly preferably, for the inventive implementation of the optical device, TIR optics (Total Internal Reflection Optik) are used, which reflect light in an outer region via a TIR structure and focus the light in an inner region as a lens. Those skilled in the art of optical systems are familiar with various approaches for focusing light from an LED in a specified tilt direction, so the details of such a structure will not be discussed below.

[0018] The surrounding optical system is preferably fixed in the area of the corresponding LED by means of a fixing mechanism. This fixing can be done directly on the circuit board. For example, the optical system can be fixed in the area of the corresponding LED by gluing, plug-in connection, screwing, form-fitting, etc.

[0019] Preferred embodiments of the lighting unit according to the invention are described below.

[0020] In a particularly preferred embodiment, the paired beam axes of the LED-optical element pairs, which are tilted relative to one another, have respectively paired different tilt directions. By adjusting the tilt directions, the arrangement according to the invention of the tilted beam axes can be achieved particularly easily during the manufacturing process.

[0021] In a particularly advantageous embodiment, each LED from at least one LED group is assigned an identically designed optical system. This embodiment enables a particularly simple and advantageous manufacturing method for the lighting unit, since different optical systems do not have to be provided. Thus, identical optical systems with the same tilt angle are used for the at least one LED group, wherein only the orientation of this tilt angle along the tilt direction may vary among the LEDs within the group. This embodiment embodies the central aspect of the lighting unit according to the invention: on a common, flat circuit board, a variable, manufacturable light field can be cost-effectively achieved using identically designed optical systems without complex tilting of the circuit board or adjustment of optical elements. To this end, it is only necessary to enable the adjustment according to the invention for different tilt directions, for example by means of different slots for the optical system and / or similar fixing mechanisms that enable different tilt directions.

[0022] In another embodiment, at least one LED from at least one group is assigned at least one other LED, which together with the at least one LED forms an LED cluster that, together with the assigned optical system, generates a common light beam having a beam axis. The arrangement of the LED clusters allows for different color tones, or color temperatures and color intensities, to be provided, for example by varying the current supply to the LEDs, which preferably have different color temperatures and whose light is combined via the optical system. The optical system preferably encompasses not only the at least one LED from the at least one LED group, but also the other LEDs within the common LED cluster. The LEDs of the LED cluster are preferably individually controllable. The LED clusters are configured to provide a common light beam having a common beam axis, making it possible to implement common surrounding optical systems simply and without additional structural obstacles.

[0023] In one embodiment, the predeterminable tilt direction is an orientation about an orientation angle within the mounting plane of the respective LED, toward which the tilt angle of the LED-optics pair is oriented. Furthermore, the tilt angle is an angle relative to the surface normal of the mounting plane of the respective LED. That is, the orientation angle within the mounting plane is the angle at which its edge lies within the mounting plane. The orientation angle can be the angle by which the optical device must be rotated during the manufacturing process of the lighting unit to define a predetermined tilt direction. By adjusting the tilt direction and tilt angle relative to the mounting plane of the respective LED, it is possible to define beam axes that are tilted relative to each other in a particularly simple manner in terms of construction. In principle, if the LED-optics pair is arranged directly on a circuit board, the mounting plane can be formed by the circuit board. Alternatively or additionally, the mounting plane can be formed by a separate mounting plate, on which at least the optical output of the LED and / or LED cluster is implemented.

[0024] In one advantageous and particularly preferred embodiment, the tilting direction can be defined by a fixing mechanism, wherein the fixing mechanism allows for reliable definition of the tilting direction by mounting the optical component in a discretely adjustable manner via corresponding contact pins. Providing contact pins is a particularly simple fixing method that can be implemented cost-effectively within a preferably at least partially automated manufacturing process. The contact pins can be arranged on the optical component and / or on the fixing mechanism, such as on a circuit board. Preferably, the contact pins are arranged asymmetrically with respect to the surface normal of the fixing plane. This asymmetrical arrangement can contribute to the torsional resistance of the correspondingly fixed optical component and thereby enhance the robustness of the lighting unit. Preferably, slots are provided on the circuit board corresponding to the positions of the contact pins, such that inserting the contact pins into the slots results in a predetermined tilting direction for the corresponding optical component. Alternatively or additionally, the contact pins can be provided on the circuit board corresponding to the positions of the slots on the optical component, such that inserting the contact pins into the slots results in a predetermined tilting direction for the corresponding optical component. As an alternative to the two examples described above, according to the present invention, corresponding slots for the contact pins allow for different possible assignments between contact pins and slots. This allows for different tilting directions of the corresponding LED-optics pair. The provision of contact pins allows the tilting direction to be directly varied into preferably at least four different tilting directions, in particular at least eight different tilting directions. The fastening of the optics via contact pins and corresponding slots is a particularly robust and easily implemented fastening method that is reliable even after sudden movements of the corresponding lighting unit in everyday clinical practice. Such fastening is preferably supported by a material-locking and / or force-locking connection, such as adhesive bonding or pressing.

[0025] In another embodiment, the tilt direction can be defined by a fixing mechanism, wherein each fixing mechanism includes a rotatable mount for the optical component, in particular a rotatable mount for the optical component on a common circuit board. The rotatable mount for the optical component allows for particularly convenient, preferably continuous, adjustment of the tilt direction during the manufacturing process of the lighting unit. Such rotatable mounting can, for example, be achieved by a form-fitting fit between the optical component and the fixing mechanism. Preferably, the rotation axis of the rotatable mount extends through the center of the respective LED-optics component pair. This allows for uniform rotation of the beam axis about the rotation axis by rotating the optical component.

[0026] Within the scope of the present invention, a fastening means is a structure that enables a positive, force-fitting, and / or material-fitting connection between the optical component and the printed circuit board or the fastening plate. Preferably, the fastening means is formed by structures on the optical component side and structures on the plate side, which interact to provide this connection.

[0027] In another embodiment, the tilt direction and / or tilt angle of at least one optical component is adjustable, in particular mechanically or electrically. Such control of the tilt direction and / or tilt angle enables dynamic adjustment of the light field. Preferably, the adjustment is performed via an electrical signal triggered by the user via an operator interface. Examples of adjustability according to the present embodiment include electrical control of a liquid lens or a motor of an adjustable optical component. Alternatively or additionally, an adjustable support can be implemented, for example, via a rotary joint or screw tightening, whereby the tilt direction and / or tilt angle can be manually adjusted.

[0028] The peripheral optical component according to the present invention is preferably formed from plastic. Particularly preferably, the peripheral optical component is manufactured using an injection molding process. Alternatively, other suitable manufacturing processes are known, such as injection-compression molding, expansion-compression molding, embossing, casting, diamond turning or milling, grinding and polishing, 3D printing, at least partial vapor deposition with a metal or dichroic mirror layer, and / or other known manufacturing processes for plastic optical components, glass optical components, or mirrors.

[0029] According to another aspect of the present invention, in order to achieve the above-mentioned object, a lamp, in particular a medical lamp, is proposed, which includes at least one lighting unit according to at least one of the above-mentioned embodiments. The lamp has a central lamp axis, wherein the light field of the lamp is generated in a plane perpendicular to the lamp axis at a light field distance from the lamp by light from the at least one lighting unit.

[0030] The lamp according to this further aspect of the invention comprises the lighting unit according to the invention and therefore also has all the advantages described for this lighting unit.

[0031] In a medical setting, the light field distance is typically a predetermined distance, which in the present case is preferably between 0.4 m and 1.5 m, particularly preferably in the range of 1 m. OP lamps typically have a light field distance of approximately 1 m. Examination lamps typically have a light field distance of approximately 0.5 m. The lamps in the context of the present invention may be, for example, OP lamps or examination lamps.

[0032] Preferably, the lighting unit according to the present invention is a component that can be easily inserted into the lamp according to the present invention. This modular design allows for a particularly simple manufacturing process for the lamp. Particularly preferably, multiple lighting units according to the present invention can be inserted into the lamp according to the present invention. In a particularly advantageous variation of this embodiment, the lamp has suitable receptacles into which corresponding lighting units can be inserted. The receptacles ensure electrical connection between the respective circuit boards of the lighting units and the electronics of the lamp according to the present invention by providing connection areas. Preferably, the receptacles also provide a large, form-fitting, and thermally conductive contact surface with at least the area of the planar circuit board near the respective LED for heat dissipation. The fixing of the receptacles defines the mechanical orientation, i.e., the tilt, of the planar circuit board relative to the lamp and the lamp axis. The modular design also enables the use of different lighting units according to the present invention with the lamp according to the present invention, for example, depending on the intended use of the lamp, such as a planned medical procedure.

[0033] The connection between the lighting unit and the lamp housing of the lamp can be achieved, for example, by screwing. Drilled holes can be provided in the corresponding printed circuit board of the corresponding lighting unit, which holes match the provided threads. Alternatively or additionally, a latching mechanism can be provided for inserting the lighting unit into the lamp.

[0034] With the lighting unit according to the invention, the light field of the lamp can be specified and / or adjusted particularly easily and cost-effectively by means of corresponding optics according to the invention for corresponding LED-optics pairs, in particular during the manufacturing process of the lamp.

[0035] In a preferred embodiment, multiple beam axes of an LED-optics pair are designed to be tilted relative to the lamp axis. This allows for the specification of particularly variable characteristic properties of the light field, such as the light field diameter, intensity distribution within the light field, illumination depth, shadows, and so on, by predefining different tilt directions. Particularly preferably, at least 10% of the beam axes of an LED-optics pair are designed to be tilted relative to the lamp axis. Alternatively or additionally, at most 90% of the beam axes of an LED-optics pair are designed to be tilted relative to the lamp axis.

[0036] In a preferred embodiment, the lamp according to the present invention comprises a plurality of identically designed lighting units according to at least one of the relevant embodiments. Such a lamp allows for particularly simple manufacture, as different lighting units do not need to be distinguished during installation. This embodiment also advantageously reduces the number of identical lighting units to be manufactured to preferably only one type. This allows for a particularly simple and advantageous manufacturing method. Finally, the use of identical lighting units results in a substantially symmetrical arrangement of the radiation beams and, therefore, symmetrical illumination of the light field.

[0037] In another advantageous embodiment, the lamp according to the present invention includes a plurality of lighting units according to at least one of the preceding embodiments, wherein the lighting units are arranged rotationally symmetrically about the lamp axis. In a preferred variant of this embodiment, the lighting units of the plurality are designed to be substantially identical. This rotationally symmetrical arrangement of the lighting units can advantageously support uniform illumination of the light field.

[0038] In one advantageous embodiment, a lamp according to the present invention includes multiple lighting units according to at least one of the relevant embodiments, wherein the LED-optics pairs of a respective lighting unit are arranged on a different planar circuit board than the planar circuit boards of another lighting unit. Providing different planar circuit boards can, for example, support a modular design of the lamp. Providing different circuit boards also allows for a particularly simple design of the electronics of the lamp according to the present invention. In a preferred variant of this embodiment, at least two different circuit boards of the lighting units of the lamp are tilted relative to each other by a board tilt angle. This board tilt angle allows the LED-optics pairs to be tilted relative to each other, so that the tilt angle of an individual LED-optics pair only achieves a dependent tilt relative to this board tilt angle. For example, if an 11.5° tilt of the LED-optics pairs relative to a plane perpendicular to the lamp axis is desired, an 11° angle of attack relative to this plane can result in the tilt angle of an individual LED-optics pair only having to be 0.5°. The necessary magnitude of the board tilt angle between the two circuit boards to achieve this angle of attack depends on the specific lamp geometry and is readily apparent to those skilled in the art. Compared to very large tilt angles, which usually lead to large optical aberrations, asymmetric beams, and poor light collection from edge regions of the beam that are far from the desired tilted beam axis, this can preferably achieve a particularly symmetrically radiated beam. Setting the angle of attack is particularly advantageous if a specific tilt angle range relative to the perpendicular to the lamp axis is set for the LED-optics pair, for example a tilt angle range between 9° and 13°. Thus, for the example described, an angle of attack of 11° can be adjusted, and the tilt angle of the corresponding optics only needs to be between 0.1° and 2°. In other words, different optics are preferably provided in this case.Figure 2 Examples of this interaction of the angle of attack of the circuit board and the tilt angle of the optics are described within the context of FIG.

[0039] An LED-optics pair that does not have an inclination angle caused by the optics due to the selected design of the lamp, for example due to the angle of attack, does not belong to at least one group according to the present invention from a plurality of groups in which the corresponding optics have a specified inclination angle. In this sense, according to the present invention, in addition to LED-optics pairs from at least one LED group, there may also be LED-optics pairs from another group with other properties and other optics, in particular optics without an inclination angle.

[0040] In a preferred embodiment, the lamp includes at least two different optical components that differ at least in terms of the tilt angles specified by the respective optical components. Providing a plurality of different tilt angles advantageously enables a particularly precisely defined light field of the lamp. In particular, optical components with different tilt angles enable regions of the lamp, such as regions of the lamp arranged annularly around the lamp center, to each have optical components with a uniquely specified tilt angle and preferably different tilt directions.

[0041] In a preferred embodiment, LED-optics pairs at the same distance from the lamp axis have corresponding beam axes that form substantially the same angle with a vertical line drawn from the position of the corresponding LED to the lamp axis. Such LED-optics pairs can form annular areas of the lamp that are particularly suitable for implementing functions within the light field and / or light field adjustment by individually energizing the LEDs. Such light field adjustment can, for example, involve changing the light field diameter, light field shape, light field distance, and / or light field color.

[0042] In a particularly preferred embodiment, the lamp further comprises a control unit configured to control at least one LED subgroup from at least one LED group in at least one lighting unit separately from other LEDs from the corresponding LED group outside of the subgroup. This control can, for example, change the light output, intensity, color, or on / off state of the correspondingly controlled LED subgroup. Advantageously, such a change occurs simultaneously for all LEDs in the LED subgroup. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The invention will now be explained in more detail with reference to advantageous exemplary embodiments schematically shown in the accompanying drawings. In these drawings:

[0044] Figure 1A schematic diagram showing a first embodiment of a lighting unit according to the invention for use with a first embodiment of a lamp according to another aspect of the invention;

[0045] Figure 2 shows cross-sectional views of different LED-optics pairs of a first embodiment of a lighting unit according to the present invention;

[0046] Figure 3 、 4 5 shows a cross-sectional view of a corresponding embodiment of an LED-optical device pair, which has a different structure of the surrounding optical device and has different fixing mechanisms;

[0047] Figure 6 A schematic diagram showing a second embodiment of a lighting unit according to the invention for a second embodiment of a lamp according to another aspect of the invention;

[0048] Figure 7 A schematic diagram showing a light beam axis and a corresponding light field of a lamp according to another embodiment;

[0049] Figure 8 A schematic diagram showing the tilt angle and tilt direction of two LED-optical device pairs according to the present invention;

[0050] Figure 9 a schematic diagram of a third embodiment of a lighting unit according to the invention showing a third embodiment of a lamp; and

[0051] Figure 10 Shows the passing Figure 9 sectional view of a lamp according to a third embodiment. DETAILED DESCRIPTION

[0052] Figure 1 A schematic diagram of a first embodiment of a lighting unit 100 according to the invention is shown for a first embodiment of a lamp 150 according to another aspect of the invention, in particular a medical lamp 150 .

[0053] The lighting unit 100 comprises a plurality of LED groups 110, 110', 110", namely in the present case three LED groups. In the present case, the LED groups 110, 110' are approximately at the same distance from a central lamp axis 160 of the lamp 150, which intersects the plane of the illustration perpendicularly. In the present case, the remaining LEDs form a third group 110". Each of these LED groups 110, 110', 110" is connected to a common planar circuit board 115 of the lighting unit 100 and is arranged completely thereon. In an alternative embodiment, the optical output of the LEDs is at least partially arranged on a fixing plate, which is connected at least to the circuit board 115, such as Figure 4As shown in .

[0054] Each LED 112, 112' in at least one group 110, 110' from the plurality of groups is assigned a corresponding surrounding optical system 122, 122', which forms a corresponding LED-optical system pair 120, 120'. In the illustrated embodiment, each group of LEDs 112, 112', 112' from the plurality of LED groups 110, 110', 110'' has a corresponding surrounding optical system 122, 122', 122'. However, the groups 110, 110' according to the present invention only have LED-optical system pairs 120, 120', wherein the corresponding optical system 122, 122' has an angle of inclination in an oblique direction due to its structure. This configuration of the optical system is described within the scope of the following exemplary embodiments.

[0055] exist Figure 1 In the figure, three areas of the receptacle 155 are also indicated by dashed lines, into which other lighting units, such as those having the same structure as the lighting unit according to the present invention, can be inserted. The receptacle 155 preferably has connection areas that ensure an electrical connection between the remaining components of the lamp 150, such as the lamp electronics (not shown) in the lamp housing, and the lighting units to be inserted. To this end, these lighting units also have electrical connections (not shown) that connect the lamp electronics to the LEDs 112, 112', 112" of the lighting unit 100 via the circuit board 115. Preferably, the respective lighting unit is inserted into the corresponding receptacle 155 via a positive and / or force-locking connection, in particular a latching mechanism. Alternatively or additionally, after insertion, it can be secured by screws, which makes it particularly easy to ensure uniform contact with the base body and thus good heat flow.

[0056] In the illustrated embodiment, the lamp 150 is designed to be circular, particularly round, when viewed from below, i.e., from the illuminated area. In an embodiment not shown, the lamp is designed to be elliptical or polygonal, particularly in the shape of a regular n-gon. Particularly preferably, the lamp is designed to be point-symmetrical about the lamp axis when viewed from below, for example, in the shape of a flower, star, or satellite.

[0057] By means of these receptacles, the lamp 150 can comprise a plurality of identically designed lighting units which can be arranged rotationally symmetrically with respect to the lamp axis 160 according to the receptacles 155 .

[0058] Each lighting unit, corresponding to lighting unit 100, is provided with its own separate circuit board 115 for electrically connecting the LEDs to the lamp's electronics (not shown). Alternatively or additionally, the electronics, or parts thereof, for operating the LEDs can already be included on a corresponding flat circuit board. For example, the LED driver can be included on the circuit board. Preferably, only the electronics for the voltage supply and the lamp control unit are located outside the lighting unit.

[0059] By such modular construction, different lighting units can be combined with one another. In addition, by this modular construction, lamps according to the present invention of different shapes can be provided, such as lamps according to lighting units of the present invention with different numbers and / or orientations.

[0060] Figure 2 Cross-sectional views of different LED-optics pairs 120 , 120 ′, 120 ″ of a first exemplary embodiment of a lighting unit 100 according to the present invention are shown.

[0061] Due to their shape, the respective peripheral optics 122, 122', 122" define the central beam axis 124, 124', 124" of the radiation beam of the corresponding LED-optics pair 120, 120', 120". The beam is formed by light rays that extend essentially along the beam axis and, in the outer region of the beam, form a divergence angle with respect to the beam axis that depends on the geometry of the optics used and on manufacturing tolerances. In this case, the beam axis 124" of the third group of LEDs 112" has no tilt angle but is oriented along the surface normal to the mounting plane, which in the present case is oriented along the circuit board 115. The two central beam axes 124, 124' of the LED-optics pairs 120, 120' according to the present invention have a tilt angle 125 relative to the surface normal to the mounting plane that is the same for both LED-optics pairs 120, 120', but oriented in different tilt directions. Thus, the beam axis 124 of the LED-optical device pair 120 of the first LED group 110 is oriented in the direction of the center of the lamp 150. In contrast, the beam axis 124 ′ of the LED-optical device pair 120 ′ of the second LED group 110 ′ is oriented in the direction of the edge region of the lamp 150. Other orientations (not shown) between these two opposite tilting directions can be realized according to the present invention, such as Figure 6 . Here, the beam axes 124, 124' do not extend completely within the plane of representation. Thus, the different tilt directions are selected such that the beam axes 124, 124' have different tilt directions into the plane of representation, so that the two beam axes are tilted relative to each other, i.e., the straight lines along which the respective beam axes 124, 124' lie do not intersect.

[0062] In the embodiment shown, the respective peripheral optics 122, 122', 122" each have a lens-shaped central region which, together with the remaining optics, forms a so-called TIR optic (total internal reflection optic) which directs the undirected light radiated by the respective LED into a beam along the corresponding beam axis 124, 124', 124". Such a TIR optic comprises a central refractive region, which is formed, for example, by a lens, and a reflective edge region. Figure 4 and 5 An alternative design is shown in .

[0063] In addition to the tilt angles of the corresponding beam axes 124, 124', there is an angle of attack 116 relative to a plane perpendicular to the lamp axis 160, at which the circuit board is tilted. In the illustrated embodiment, this angle of attack 116 is between 4° and 20°, particularly between 8° and 14°, and preferably approximately 11°. Thus, the different tilt directions of the two optical elements 122, 122' result in two different tilt angles of the corresponding beam axis relative to the lamp, each having the same angular distance from angle of attack 116. Thus, according to the present invention, different tilt angles can be provided for the lamp's light field using the same optical elements but with correspondingly specified tilt angles. By providing the additional angle of attack 116 at which the circuit board is tilted, the angular band can be adjusted accordingly by adjusting the tilt direction, varying between the angle of attack minus the tilt angle of the corresponding optical element and the angle of attack plus the tilt angle of the corresponding optical element. Thus, according to the invention, a plurality of possible tilt angles of the corresponding beam axis relative to the lamp can be realized using only one optical component to be produced, namely an optical element with a predetermined tilt angle.

[0064] In other exemplary embodiments, at least two different optical systems are provided for the lamp according to the invention, which differ at least in terms of their angle of inclination.

[0065] The following exemplary embodiments illustrate various embodiments for fastening corresponding optical components to form an LED-optical component pair according to the invention.

[0066] Figure 3 、 4 5 show cross-sectional views of respective embodiments of LED-optics pairs 320 , 420 , 520 with different configurations 328 , 428 , 528 of the surrounding optics 322 , 422 , 522 and with different fixing mechanisms 340 , 440 , 540 .

[0067] Figure 3A tilted TIR optic 322 with a central lens-shaped region is shown, as it is in principle in Figure 2 As already shown in FIG. For clarity, the optical component is shown in cross-section, while the circuit board is shown in perspective. While the angle at which the optical component's geometry is tilted is related to the tilt angle provided by the optical component, it is not necessarily identical to that tilt angle. However, in this case, a fixing mechanism 340 for securing the optical component 322 to the circuit board 150 is also shown. Thus, the optical component 322 has at least two contact pins 342, preferably three, which can each be inserted into a slot 344 provided on the circuit board 115 to surround the LED 112 arranged on the circuit board 115. Providing at least three contact pins can additionally improve the torsional resistance of the optical component. By providing different slots 344, different tilt directions of the tilt angle of the optical component 322 can be specified. Due to the discrete provision of slots 344, a discrete, predetermined number of different tilt directions can be specified for the illustrated LED-optical component pair 320, particularly within the context of lamp manufacturing. Alternatively, the desired tilting direction can already be taken into account during the manufacture of the circuit board, so that only slots corresponding to the positions provided for the contact pins are provided for this tilting direction. This avoids errors during manual fixing of the optical component during manufacture.

[0068] Figure 4 An optical device 422 is shown which emits the light of the corresponding LED 112 along a predetermined beam axis at a predetermined tilt angle due to a reflector 423, preferably a parabolic mirror, an aspherical mirror and / or a free-form mirror. To provide the tilt angle, the reflector is preferably designed asymmetrically.

[0069] The reflector 423 is fixed to the fixing plate 417 via a fixing mechanism 440. In the present case, the fixing mechanism 440 comprises an annular portion 442 having a groove 444′, into which a corresponding optical component can engage, so that the optical component 422 is fixed by latching it into the annular portion 442. Alternatively, a commercially available LED-optics socket can also be used to fix the optical component in the lighting unit according to the present invention. Preferably, in the embodiment shown, the fixing mechanism 440 enables rotatable mounting of the optical component, so that different tilting directions of the LED-optics pair 420 can be consistently specified.

[0070] Figure 4It is also shown that the fixing plate 417 can be different from the circuit board 415. Thus, in the illustrated embodiment, the LEDs 412 are arranged on the circuit board 415, and the light is guided to the fixing plate 417 via glass fibers 419 for a corresponding optical output 470. In an embodiment not shown, the angle between the fixing plate and the circuit board is adjustable by a control unit of the lamp.

[0071] In this case, the LEDs 412 form an LED cluster that generates a common light beam with a beam axis via an associated optical device 422. Alternatively, the light of the LED clusters can be mixed in a single optical fiber. For this purpose, fiber optic rods or the like can be used, as is known.

[0072] Figure 5 An optical device 522 is shown, which is formed by a tilted lens with an asymmetrical mount. The asymmetrical mount is bonded to the circuit board so that the fixing mechanism 540 is formed by a flat joint of the mount. In this case, the optical device 522 can be controlled by an adjustment unit 580 and thus rotated after receiving a corresponding signal. In the embodiment shown, the asymmetrical mount is also adjustable by the adjustment unit 580. This allows the tilt of the lens to be varied. In this case, the rotation and tilting are mechanically achieved by a motor (not shown) that is controlled by the adjustment unit 580.

[0073] Figure 6 A schematic diagram of a second embodiment of a lighting unit 600 according to the invention is shown for a second embodiment of a lamp 650 according to another aspect of the invention, from a viewing direction of the light field along the lamp axis.

[0074] Lighting unit 600 and Figure 1 The lighting unit 100 in FIG. 1 differs in that a greater number of LEDs 612 are provided and can be controlled in groups by a central control unit 690 of the lamp 650. In this case, at least two LED groups 610, 610' are provided in each of the three identically shown lighting units 600 having LED-optical system pairs 620, 620' according to the invention, based on the LEDs shown. For the sake of clarity, only the features of the corresponding lighting unit are shown for lighting unit 600. These features are present in FIG. Figure 6 The tilt angles (not shown) in FIG and each have a tilt direction 627, which is indicated in the diagram by corresponding arrows on the LED-optics pair 620, 620', which is different for the LED-optics pair also within the LED group 610, 610'. In this case, the tilt direction 627 is the direction in which the tilt angle of the LED is oriented within the mounting plane of the corresponding LED. This interaction of the tilt angle and the tilt direction has already been described. Figure 2 is elaborated within the scope of Figure 8 . In particular, the corresponding beam axes (not shown) of the respective LED-optics pairs are designed to be tilted relative to one another. In particular, LED-optics pairs at the same distance from the lamp axis have corresponding beam axes 160 that form corresponding angles of substantially the same magnitude with a plumb line from the position of the respective LED to the lamp axis. This orientation also results in the angles of the plumb line to the tilt direction having substantially the same magnitude. Figure 7 An exemplary arrangement of the beam axis for a similar orientation of the tilt direction is shown in .

[0075] Furthermore, a handle 665 of the lamp 650 is arranged in the region of the lamp axis 160 , which handle is designed to adjust the position of the lamp 650 during use, for example in an operating room.

[0076] The control unit 690 is designed to drive at least one LED subgroup 611 from at least one LED group 610 , 610 ′ in at least one lighting unit 600 separately from other LEDs outside the subgroup 611 from the corresponding LED group 610 , 610 ′.

[0077] Alternatively or additionally, the LED groups 610 , 610 ′ can also be driven differently, wherein, by this driving, for example, the light output, intensity, color, color temperature or on / off state of the correspondingly driven LED subgroup 611 can be changed.

[0078] By means of such group control and / or by means of control of subgroups of LEDs from an LED group according to the invention, it is possible to ensure a particularly advantageous illumination of the light field by the lamp according to the invention with a lighting unit according to the invention, such as 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 distribution of the light, etc. In this case, an in particular annular region of uniform light intensity can be provided by the LED group 610 , 610 ′ according to the invention.

[0079] Preferably, the tilt angles of the LED groups shown are substantially identical. Alternatively, in addition to the choice of the respective tilt direction, the LED groups 610 and 610 ′ differ in their tilt angles, which are not shown. In the present case, the optics 622 of group 610 differ from the optics 622 ′ of the other group 610 ′ in their respective tilt angles.

[0080] The lighting units 600, 600' of the lamp 650 are designed identically. Here, the circuit boards 615, 615' of the lighting units 600, 600' form separate circuit boards 615, 615' which, in the illustrated embodiment, are tilted relative to one another at a not illustrated board tilt angle.

[0081] Figure 7 A schematic diagram shows a beam axis 724 and a corresponding light field 775 of a lamp according to the invention (not shown) according to another exemplary embodiment.

[0082] In the exemplary embodiment shown, the illustrated orientation of the tilt angles of the respective LED-optics pairs 720 , which is identical to the lamp axis 160 , results in a saddle region 777 that is particularly narrow compared to the extent of the present lamp.

[0083] Advantageously, the lamp according to the present invention can provide a high radiation intensity for the light field within a range of distances differing from the light field distance 779. A point-like orientation of the beam axis at a single point causes a sharp drop in intensity around that point. This effect can be avoided by the annular illumination shown. Different groups of LED-optics pairs can provide different annular illumination areas, thereby advantageously enabling large areas within the light field to have a high intensity compared to the edges of the light field. Advantageously, the light field distance 779 is between 80 cm and 1.30 m, in particular between 90 cm and 1.10 m, and particularly preferably approximately 1 m. The light field 775 is preferably within or near the saddle-shaped area 777.

[0084] The orientation of the tilt direction 727 is similar to Figure 6 The tilt directions 627 of the LED groups 610 in FIG. 7 are oriented so that LED-optics pairs 720 at the same distance from the lamp axis 160 have corresponding beam axes 724 that form corresponding angles of substantially the same magnitude with the position of the corresponding LED relative to the vertical line of the lamp axis 160. The annular region of illumination thus formed within the region of the light field 775 is essentially defined by the substantially identical tilt directions 727 of the LED-optics pairs 720 and the corresponding tilt angles.

[0085] In addition to the exemplary LED group shown, other LED groups can correspondingly create other annularly illuminated areas in the environment of the light field 775. In this case, the control unit preferably allows the corresponding LED combination and / or corresponding subgroup of the LED group to be actuated, so that the characteristics of the current lighting can be controlled, for example temporarily, by the lamp.

[0086] Figure 8A schematic diagram shows an inclination angle 825 and an inclination direction 827 , 827 ′ of two LED-optics pairs according to the invention. The explanations regarding this diagram are fundamental to the present invention and are therefore valid analogously for all exemplary embodiments and specific embodiments.

[0087] According to the present invention, LEDs 812, 812' are arranged on a circuit board 815. The illustrated optics of the two LED-optics pairs have an identical structure and therefore have the same tilt angle 825. However, the two optics differ in their orientation and therefore in their tilt directions 827, 827'.

[0088] The two LED-optics pairs each emit light beams with beam axes 824 and 824', which are tilted relative to each other and have spatial angles relative to the circuit board normal. These spatial angles can be described using spherical coordinates. This section explains the terms tilt direction and tilt angle for the purposes of this disclosure. For this description using spherical coordinates, the plane formed by circuit board 815 is shifted parallel to the respective centers of the light exit planes of the optical devices, representing the equatorial plane. The corresponding surface normals passing through the centers of the LEDs 812 and 812' are the polar axes. The solid angles of beam axes 824 and 824' can then be described using azimuth angles 884 and 884' (longitude) and polar angles 888 (latitude). If both use the same optical devices, they also have the same polar angle 888, meaning, for the purposes of this disclosure, the same tilt angle 825. In other words, tilt angle 825 and polar angle 888 are identical for the purposes of this disclosure. Tilt angle 825 is a characteristic of the optical devices. An additional degree of freedom arises from the rotation of the optical components about the polar axis, i.e., about the circuit board normal, which differs by an azimuth angle 884, 884', preferably during the mounting of the corresponding optical components on the circuit board. If the two optical components have the same azimuth angle 884, 884', the beam axes 824, 824' run parallel. If the angles differ by 180°, they intersect at a point in space, and the two beam axes 824, 824' are not tilted relative to one another. If the azimuth angles 884, 884' do not differ by 0° or 180°, the beam axes 824, 824' run tilted relative to one another. For the purposes of the present invention, the azimuth angles 884, 884' describe the tilt directions 827, 827'. Embodiments of the present invention include lighting units having at least one set of identical optical components and, therefore, also the same tilt angle 824, but simultaneously having pairwise different tilt directions 827, 827'.

[0089] Figure 9 A schematic diagram of a third exemplary embodiment of a lighting unit 900 according to the invention is shown for a third exemplary embodiment of a lamp 950 .

[0090] Lighting units 900 are present in multiple identical designs in lamps 950. For the sake of clarity, the structure of LED-optics pairs 920, each with a different tilt direction 927 within the respective lighting unit, is not shown in detail. 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, therefore, without tilt direction.

[0091] The lighting unit 900 is arranged rotationally symmetrically with respect to the lamp axis 160 .

[0092] from Figure 10 The cross-sectional view in FIG. 9 shows the effect of the change in tilt direction 927 on the radiation direction of the provided light beam.

[0093] In addition to the rotationally symmetrically arranged lighting units 900, the lamp 950 has a central lighting unit 900' which is designed at least partially annularly around the lamp axis 160. The tilt angle 925' of the LED-optics pair 920' of the central lighting unit 900' differs from the tilt angle 925 of the LED-optics pair 920 of the rotationally symmetrically arranged lighting unit 900, as shown in FIG. Figure 10 For two beams marked with tilt angles 925 and 925', Figure 10 The corresponding tilt angle can be seen in the figure because the corresponding tilt direction 927 is based on Figure 9 Substantially parallel to section line 980 .

[0094] Finally, in Figure 10 The arrangement of the LED-optical device pairs on the corresponding circuit boards 915, 915' is also shown in FIG. Here, the circuit boards 915 of the lighting units 900 and the circuit boards (Festplatte) 915' of the central lighting unit 900' arranged in rotational symmetry have a board inclination angle 975 relative to each other. In addition, Figure 10 9 also shows an advantageous direct connection between the circuit boards 915, 915' and the base body 990 of the lamp 950. The base body 990 serves as a heat sink for the lamp 950, ensuring a heat flow from the LEDs toward the base body 990. Advantageous materials for designing the components of the lamp 950 are known to those skilled in the art, so this will not be discussed further below.

[0095] Thus, the light beams of different LED-optics pairs and their different tilt angles and tilt directions are also shown. Figure 9 and 10 It is also not clearly visible in FIG. 9 that some of the beam axes shown are also tilted in pairs from one another, so that they do not intersect in the space in front of the lamp 950 .

[0096] The structure of the corresponding optics may vary for different LED-optics pairs.

[0097] List of Reference Numerals

[0098] 100, 600, 600', 900, 900' lighting units

[0099] 110, 110', 110'', 610, 610' LED groups

[0100] 112, 112', 112'', 412, 812, 812' LED

[0101] 115, 415, 615, 615', 815, 915, 915' circuit boards

[0102] 116 Angle of Attack

[0103] 120, 120', 320, 420, 520, 620, 620', 720, 920, 920' LED-optical device pairs

[0104] 122, 122', 122'', 322, 422, 522, 622, 622' optical devices

[0105] 124, 124', 124'', 724, 824, 824', 924 beam axis

[0106] 125, 825, 925, 925' tilt angle

[0107] 150, 650, 950 lamps

[0108] 155 Receptacle for lighting unit

[0109] 160 Light Axis

[0110] 328, 428, 528 optical device structure

[0111] 340, 440, 540 fixing mechanism

[0112] 342 contact pin

[0113] 344 slots

[0114] 417 fixed plate

[0115] 419 Fiberglass

[0116] 423 Mirror Wall

[0117] 442 ring part

[0118] 444 groove

[0119] 470 Optical Output

[0120] 580 adjustment unit

[0121] 627, 727, 827, 827' 927 tilt direction

[0122] 611 LED subgroup

[0123] 665 handle

[0124] 690 Control Unit

[0125] 775 Light Field

[0126] 777 Saddle Area

[0127] 779 Light Field Distance

[0128] 884, 884' polar angle

[0129] 888 Azimuth

[0130] 921 LED-optics pair without tilt angle

[0131] 975 Plate tilt angle

[0132] 980 hatching

[0133] 990 lamp base

Claims

1. A lighting unit for a medical lamp having a plurality of LED groups, wherein the plurality of LED groups are connected to a common planar circuit board, wherein each LED of at least one LED group from the plurality of LED groups is assigned a corresponding surrounding optical device, with which a corresponding LED-optical device pair is formed, The corresponding optical device specifies, based on its structure, an inclination angle of a central beam axis of the radiation beam of the LED-optical device pair toward an inclination direction of the corresponding LED-optical device pair, wherein the inclination direction of the corresponding optical device is specified so that the corresponding beam axes of the radiation beams of the LED-optical device pairs from at least one LED group do not intersect with each other in space and are not parallel to each other even when taking into account manufacturing tolerances. 2 . The lighting unit according to claim 1 , wherein the beam axes of the LED-optical element pairs, which do not intersect one another in space and are not parallel to one another even when taking into account manufacturing tolerances, have inclination directions that are different in pairs. 3 . The lighting unit according to claim 1 , wherein each LED from at least one LED group is assigned an identically designed optical element.

4. A lighting unit according to claim 1 or 2, wherein at least one LED from the at least one LED group is assigned at least one other LED, and the at least one other LED forms an LED cluster with the at least one LED, and the LED cluster together with the assigned optical device generates a common light beam with a light beam axis.

5. The lighting unit according to claim 1 or 2, wherein the prescribed tilt direction is an orientation around an orientation angle in a fixing plane of the corresponding LED, the tilt angle of the LED-optics pair being oriented in the direction of the orientation angle.

6. The lighting unit according to claim 1 or 2, wherein the tilting direction can be defined by a fixing mechanism, and wherein the fixing mechanism allows a reliable definition of the tilting direction by means of a mounting of the optical device that can be discontinuously adjusted via corresponding contact pins. 7 . The lighting unit according to claim 1 , wherein the tilting direction can be defined by a fixing mechanism, and wherein the fixing mechanism each comprises a rotatable mounting of the optical element. 8 . The lighting unit according to claim 7 , wherein the rotatable mounting is a rotatable mounting of the optical system on a common circuit board.

9. The lighting unit according to claim 1 or 2, wherein the tilt direction and / or the value of the tilt angle of at least one optical component can be adjusted.

10. The lighting unit according to claim 9, wherein the tilt direction and / or the value of the tilt angle of the at least one optical device can be adjusted mechanically or electrically.

11. A lamp comprising at least one lighting unit according to any one of claims 1 to 10, wherein the lamp has a central lamp axis, and wherein the light field of the lamp is generated by light from at least one lighting unit within a light field distance of the lamp in a plane perpendicular to the lamp axis.

12. The lamp of claim 11, wherein the lamp is a medical lamp. 13 . The lamp according to claim 11 , wherein the plurality of beam axes of the LED-optical device pair are designed not to intersect in space relative to the lamp axis and not to be parallel to each other even in consideration of manufacturing tolerances. 14 . The lamp according to claim 11 , comprising a plurality of identically designed lighting units according to claim 1 .

15. The lamp according to any one of claims 11 to 13, comprising a plurality of lighting units according to any one of claims 1 to 10, wherein the lighting units are arranged rotationally symmetrically with respect to the lamp axis.

16. The lamp according to any one of claims 11 to 13, comprising a plurality of lighting units according to any one of claims 1 to 10, wherein the LED-optics pairs of a respective lighting unit are arranged on a planar circuit board that is different from the planar circuit board of another lighting unit.

17. The lamp according to claim 16, wherein at least two different circuit boards of a lighting unit of the lamp are tilted with respect to each other by a board tilt angle.

18. The lamp according to any one of claims 11 to 13, wherein the lamp comprises at least two different optical devices, which differ at least in the tilt angle specified by the respective optical device.

19. The lamp according to any one of claims 11 to 13, wherein LED-optics pairs having the same distance from the lamp axis have respective beam axes which form angles of substantially the same value with a plumb line from the position of the respective LED to the lamp axis.

20. A lamp according to any one of claims 11 to 13, comprising a control unit designed to control at least one LED subgroup from at least one LED group in at least one lighting unit separately from other LEDs outside the subgroup from the corresponding LED group.

Images