Lighting device

Abstract

The present invention relates generally to slotted spotlights for illuminating a room through a narrow slot. The invention relates in particular to a lighting device with a slotted panel having at least one slotted light emission opening, an elongated light source arrangement, and an elongated, extruded-profile lens, wherein the light source arrangement and the lens are arranged behind the slotted panel and extend along the slotted light emission opening, and the lens is configured to emit a constricted beam of light rays that tapers away from the lens towards the slotted panel, passes through the slotted light emission opening, and widens again away from the slotted panel.According to the invention, a series of optical longitudinal baffles are provided between the light source arrangement and the aforementioned elongated, extruded-profile lens for limiting the light rays in the light beam in cross-sectional planes parallel to the longitudinal extension of the slit-shaped light exit aperture to a narrowed light ray area.

Description

[0001] The present invention generally relates to slot spotlights for illuminating a room through a narrow slot. More particularly, the invention relates to a lighting device comprising a slot panel with at least one slot-shaped light exit opening, an elongated light source arrangement, and an elongated, extruded-profile lens. The light source arrangement and the lens are arranged in a concealed manner behind the slot panel and extend along the slot-shaped light exit opening. The lens is configured to emit a constricted bundle of light rays that tapers away from the lens toward the slot panel, passes through the slot-shaped light exit opening, and widens again away from the slot panel.

[0002] Such linear slot spotlights are often concealed behind ceiling panels, but occasionally also behind wall panels, so that the actual optical equipment of the lighting device, including light sources, lenses, and possibly other optical beam formers such as reflectors, are not visible or concealed from the room to be illuminated. The slit-shaped light exit opening, with its slit width, can be considerably smaller than the width of the lens, which is located behind the panel and forms the light beam. This not only creates a wide range of possibilities for aesthetic interior design with clear, uncluttered ceiling or wall surfaces, but also enables uniform, sufficiently bright, yet largely glare-free room illumination, since people in the room cannot look directly into the light sources through the narrow slit, except in certain positions and viewing directions.In a similar way, such slotted panels are also installed on luminaire housings themselves, for example on linear or elongated pendant luminaires, in order to leave only a slot-shaped exit opening for the light on the light exit side of the luminaire housing.

[0003] In terms of their lighting requirements, such slot spotlights differ fundamentally from conventional spotlights with a luminaire housing, which also often has a slot. See, for example, DE 10 2005 006 758 A1, which shows a cylindrical luminaire housing with a light exit slot through which light is to be emitted with the help of a prism. However, unlike ceiling and wall panels with light slots, the aim is not to conceal the light source while still achieving uniform, sufficiently bright, and largely glare-free room illumination. Therefore, the aforementioned document does not feature an hourglass-like constriction of the light cone to direct the light generated by an optic hidden behind the panel, which is much larger than the slot, through the narrow slot.

[0004] In order to efficiently direct the light through the narrow slits of a ceiling or wall panel and to avoid losses due to irradiation of the back of the slit panel, the lens constricts the light beam in an hourglass-like or double-wedge shape to such an extent that the thickness of the overall extruded profile-like beam in the area of ​​the slit is smaller than the slit width and the light beam widens again after passing through the slit-shaped light exit opening in order to illuminate a sufficiently large area in the room or on the room surface to be illuminated.

[0005] So-called pinhole spotlights work according to a similar principle, although the light exit opening is not slit-shaped but hole-shaped, see for example EP 2 031 296 B1, which captures the light from an LED with a cup-shaped lens and constricts it into a double-cone-like light beam, or EP 3 139 084 B1, which uses a multi-coloured LED cluster as the light source, the light from which is then also completely captured by a cup-shaped lens and constricted into a double-cone-like beam, so that the light beam initially tapers conically towards the panel, passes through the exit hole and then widens again away from the panel.

[0006] In a linear slot light, this constriction principle is extended to achieve the most uniform, linear light emission possible across the length of the slot-shaped light exit opening. The beam is not a constricted double cone, but rather—at least approximately—an elongated, roughly extruded, constricted double wedge. The elongated, extruded-profile-like lens essentially consistently constricts the light coming from the light source arrangement in planes perpendicular to the longitudinal extent of the slot, so that the beam—viewed in said planes perpendicular to the longitudinal extent of the slot—constricts toward the slot panel, passes through the slot, and widens again after the slot.The light beam essentially has the shape of an elongated double wedge, which has two wedge sections arranged parallel to the longitudinal extent of the slit, which are arranged with their narrow sides on top of each other or, in the transition to each other, form the linear constriction of the double wedge, which lies in the area of ​​the slit-shaped light exit opening.

[0007] The light source arrangement can comprise a plurality of point light sources, such as LEDs, arranged along the longitudinal extent of the slit-shaped light exit opening behind the slit panel, in particular along a line extending parallel to the slit-shaped longitudinal recess. Individual LEDs, but also multi-chip LED assemblies, for example, with differently colored LED chips or LED strips, can be used as light sources and arranged along the slit-shaped light exit opening.

[0008] The lens mentioned can be placed with a groove-shaped light entry recess over the lined-up light sources or over the light source arrangement in order to essentially completely capture the light emitted by the light source arrangement and to constrict it in the manner mentioned so that the entire light fits through the slit-shaped light exit recess of the slit panel.

[0009] Due to its linear, elongated, extruded-profile design, the lens can create an overall uniform, linear appearance. Such spotlights with elongated lenses are shown, for example, in DE 43 18 174 A1, DE 10 2017 125 236 A1, and DE 20 2016 002 197 U1. However, these do not suffer from the aforementioned problem of light passing through a slit that is inherently too narrow, so the lenses do not produce an hourglass-like or double-wedge-shaped constriction of the light cone.

[0010] However, such linear slot spotlights can cause longitudinal glare if a person in the room stands in the extension of a vertical plane through the slot and looks diagonally upwards into the slot. For example, if a slot spotlight is installed in a long hallway with a slot-shaped light outlet extending parallel to the length of the hallway and, for example, across the entire hallway, a person standing at one end of the hallway can look at relatively shallow angles into more distant sections of the slot-shaped light outlet, resulting in corresponding glare. More precisely, glare can occur if the view is directed flatly into the slot in a longitudinal plane containing the slot.

[0011] If the slit-shaped light exit opening does not have a straight course, but a curved, arched or even zigzag course, for example in order to follow corners or curves of the room, corresponding glare phenomena can also occur if a person is not standing vertically under the light exit slit in the ceiling, but rather in an upright plane tangential to a curved slit section or in the extension of such a tangential, vertical plane and is looking flat into the respective slit section.

[0012] Based on this, the present invention is based on the object of creating an improved lighting device of the aforementioned type that avoids the disadvantages of the prior art and advantageously develops them further. In particular, a slotted spotlight with a uniform, linear appearance is to be created that can provide uniform room illumination without glare.

[0013] According to the invention, the stated object is achieved by a lighting device according to claim 1. Preferred embodiments of the invention are the subject of the dependent claims.

[0014] It is therefore proposed to pre-shape the light entering the elongated, extruded-profile lens in order to achieve a longitudinal shielding effect that the elongated, extruded-profile lens itself lacks. Through the elongated, extruded-profile lens, the light could exit undirected and thus very flat in longitudinal planes parallel to the longitudinal extension of the slit, causing glare. However, this can be corrected by pre-shaping the light entering the elongated lens, so that light deflection that eliminates or reduces the glare effect can also occur in sectional planes parallel to the longitudinal extension.

[0015] According to the invention, a series of optical longitudinal glare control means are provided between the light source arrangement and said elongated, extruded-profile lens for limiting the light rays in the light beam bundle in sectional planes parallel to the longitudinal extension of the slit-shaped light exit opening to a narrowed light beam region. The longitudinal glare control means between the light source arrangement and the elongated lens allow the beam angles of the light entering the elongated lens to be limited in said sectional planes parallel to the longitudinal direction to prevent longitudinal glare.

[0016] By mounting the entire optical system behind the slit, the luminaire's structure can be concealed within the ceiling. Only the visual impression of a luminous line remains. The slit also allows the luminaire to be completely hidden in the transverse direction once the beam is cleared.

[0017] The said longitudinal masking means on the one hand and the elongated lens on the other hand can direct the light rays in different directions or cutting planes and can complement each other in a combinatorial manner, wherein in particular it can also be provided that the longitudinal masking means develops a light-directing effect only in the directions or cutting planes in which the elongated lens cannot develop a light-directing effect and / or the elongated lens develops a light-directing effect only in the directions or cutting planes in which the longitudinal masking means do not develop a light-directing effect.

[0018] In an advantageous development of the invention, the longitudinal suppression means can be designed to leave the light beam transverse to the longitudinal extent of the slit-shaped light exit opening essentially unaffected and to provide a restriction of the emission area essentially only in sectional planes parallel to the longitudinal extent of the slit-shaped light exit opening. In particular, the light coming from the light source arrangement can pass through the longitudinal suppression means unaffected in sectional planes perpendicular to the said longitudinal direction of the light exit slit and / or pass through diffusely and thus reach the elongated lens diffusely. The said longitudinal suppression means can therefore be designed to leave the Lambertian distribution of the light in sectional planes perpendicular to the longitudinal extent of the light exit slit, just as the light comes from the light source arrangement orwhen the light comes from the light source arrangement with such a Lambertian distribution.

[0019] The said elongated lens can then take over the shaping of the light beam in the said cutting planes perpendicular to the longitudinal extent of the light exit slit in the desired manner, namely to constrict or bundle it towards the light exit slit, so that the light beam shows a constriction in the area of ​​the light exit slit and can therefore "pass through" the narrow light exit slit and widen again away from the light exit slit.

[0020] The series of longitudinal masking means can have a light-bundling effect in the cutting planes parallel to the longitudinal extent of the slit-shaped light exit opening and / or limit the light rays to a range of 2 x 70° or less or to 2 x 60° or less or to 2 x 45° or less around the main emission direction, wherein the light beam range predetermined by the longitudinal masking means, limited or narrowed in the cutting planes parallel to the longitudinal direction, can be limited to an angular range of 2 x 25° to 2 x 55° or 2 x 35° to 2 x 50° to the said main emission direction.

[0021] The said main radiation direction can in particular be aligned perpendicular to the slotted panel if the said slotted panel is flat or perpendicular to a tangential plane which is tangential to the slotted panel in the region of the slot-shaped light exit opening.

[0022] Alternatively, the main beam direction can also be angled at an acute angle to the slotted panel or the tangential plane, for example, at an angle of 60° to 89° or 70° to 85°. Such an angled main beam direction can be useful if the area to be illuminated is offset from the position of the panel slot. For example, a wall panel can have a slit-shaped light exit opening relatively high or close to the adjacent ceiling, in which case the main beam direction can be directed diagonally downwards into the room to be illuminated.

[0023] However, the mentioned main radiation direction can also be selected independently of the slotted panel and, for example, be the main radiation direction of the light source arrangement.

[0024] In an advantageous development of the invention, the aforementioned longitudinal blocking means can comprise a series of longitudinal blocking lenses, which can be lined up along the longitudinal extent of the slit-shaped light exit opening and arranged between the light source arrangement and the elongated, extruded-profile lens. Such longitudinal blocking lenses allow efficient light guidance or shaping without significant optical losses, wherein the longitudinal blocking lenses can be designed, in particular, to essentially completely capture the light coming from the light source arrangement and to radiate it essentially completely onto the downstream, elongated, extruded-profile lens. This results in very low optical losses and, accordingly, a high optical efficiency of the lighting device.

[0025] The longitudinal suppression lenses can be designed as free-form lenses which have a focusing effect in planes parallel to the longitudinal direction of the light exit slit and can emit diffusely in sectional planes perpendicular to the said longitudinal direction or can leave it at a Lambertian distribution.

[0026] The longitudinal blanking lenses can, for example, have a concave light entry recess and an overall convex light exit surface and can be placed or slipped over the light sources of the light source arrangement with their concave light entry recess in order to essentially completely capture the light emitted by the light sources.

[0027] For example, the light source arrangement can comprise a series of point-shaped light sources, for example in the form of LEDs. In this case, each point-shaped light source can be assigned a longitudinal blanking lens, which can be placed or fitted over the respective light source in the manner mentioned. For example, if multi-chip LED light source components are used and arranged in series one behind the other to form the light source arrangement along the light exit slit, a longitudinal blanking lens can also be assigned to a multi-chip component and, in this case, placed over several LED chips of such a multi-chip LED component.

[0028] The longitudinal blanking lenses mentioned are therefore not the integral exit lenses of the LED components themselves, which are always present in LED components and are sometimes referred to as LED primary lenses, but rather downstream lens components which are downstream of the LED's own primary lenses and can be designed separately from them.

[0029] To facilitate assembly, the longitudinal suppression lenses can be combined into a lens array and / or form a strip- or band-shaped lens component comprising the aforementioned longitudinal suppression lenses arranged one behind the other in an array. For example, the row of longitudinal suppression lenses can be part of an injection-molded plastic lens strip, although the longitudinal suppression lenses can also be made of glass.

[0030] However, the aforementioned longitudinal blocking means do not necessarily have to be designed in the form of longitudinal blocking lenses or consist of such lenses, but can also comprise other types of longitudinal blocking means. For example, as an alternative or in addition to longitudinal blocking lenses, the longitudinal blocking means can also comprise a series of reflectors that can be lined up along the longitudinal extent of the slit-shaped light exit opening and reflect a portion of the light coming from the light source arrangement and redirect it into the elongated, extruded-profile lens. In particular, the aforementioned reflectors can focus the captured light in planes parallel to the longitudinal extent of the light exit slit and radiate it into the elongated, extruded-profile lens in a narrowed radiation area.In the transverse planes perpendicular to them, the reflectors can be cut out in order to allow the light coming from the light source arrangement to reach the elongated, extruded profile-like main lens without being directed.

[0031] Alternatively or additionally, the longitudinal shielding means may also comprise a series of shields which may have an absorbing effect and / or may comprise, for example, black shielding modules which may shield flat-angled light rays in sectional planes parallel to the longitudinal direction of the light exit slot.

[0032] The reflectors and / or shaders mentioned can also be combined with the lenses described above, for example by using free-form lenses with a reflective coating on the outside, or by arranging lenses and reflectors alternately, or by using a series of free-form lenses with small shaders between each of them.

[0033] The elongated, extruded-profile lens can fundamentally be designed in various ways, with the extruded-profile lens preferably extending over the entire length of the slit-shaped light exit opening. The elongated lens can be much longer than it is wide or high. For example, a length / width ratio and / or a length / height ratio can be greater than 10 or even greater than 50. The width refers to the transverse extent of the elongated lens perpendicular to the main emission direction, while the height refers to the extension of the lens parallel to the main emission direction. The length of the elongated lens can, in particular, be its extension parallel to the longitudinal extension of the slit-shaped light exit opening.

[0034] In order to essentially completely process the light coming from the light source arrangement or the light pre-shaped by the longitudinal blocking means and to minimize light losses, the extruded profile-like lens can advantageously have a groove-shaped, elongated light entry recess with which the elongated lens can be seated over the light source arrangement. In particular, the row of longitudinal blocking means can be at least partially accommodated in the groove-shaped light entry recess of the lens and / or the elongated lens with its groove-shaped light entry recess can be slipped over the longitudinal blocking means. This can ensure that the elongated lens essentially completely captures the light emitted by the light source arrangement as a whole and then further focuses or constricts it towards the slotted panel in the manner mentioned.

[0035] The elongated, extruded-profile lens can have a constriction degree of approximately 1.2 to 2.5, 1.3 to 2.4, or 1.6 to 2.2. The constriction degree refers to the ratio of the beam diameter at the light exit surface of the elongated lens to the minimum beam diameter in the area of ​​the slit-shaped light exit opening of the slit panel, in each case in sectional planes perpendicular to the longitudinal extent of the slit-shaped light exit opening. Such a constriction degree allows, on the one hand, the elongated lens to be constructed sufficiently large to operate and be manufactured efficiently in terms of lighting technology, while, on the other hand, reliably transmitting light through the light exit slot can be achieved with conventional slot dimensions in ceiling or wall panels.

[0036] The longitudinal masking means, on the one hand, and the elongated lens, on the other hand, can form separate components. Irrespective of this, the longitudinal masking means and the elongated lens can be rigidly connected to one another, wherein the elongated lens and / or the longitudinal masking means can comprise connecting and / or coupling and / or fastening means to fasten the elongated lens and the longitudinal masking means to one another and / or position them relative to one another.

[0037] For example, positive positioning and / or fastening means that can be brought into engagement with one another and / or interact with one another can be provided on the elongated lens and the longitudinal blanking means.

[0038] For example, nestable connecting flanges can be provided on the elongated lens and the longitudinal blanking means. If the longitudinal blanking means, for example the described longitudinal blanking lenses, form a ribbon- or strip-shaped component, the ribbon- or strip-shaped component can, for example, have lateral circuit board flanges on which coupling webs can be formed, into which the elongated lens can be inserted with matching mating webs.

[0039] Regardless of the specific mounting method, the longitudinal blocking means can be positioned at a distance from the light entry surface of the elongated lens. For example, if longitudinal blocking lenses are used, for example, in the form of drop-shaped freeform lenses, the light exit surface of the longitudinal blocking lenses can be spaced from the light entry surface of the elongated, extruded-profile lens.

[0040] The light source arrangement can again be arranged at a distance from the longitudinal blanking means. For example, the light entry surface of the aforementioned longitudinal blanking lenses can be positioned, for example in the form of drop-shaped freeform lenses, away from the light exit surface of the LED components or the point light sources.

[0041] In an advantageous development of the invention, the elongated, extruded profile-like lens, the series of longitudinal blanking means and the light source arrangement can together form a pre-assembled assembly and / or can be assembled together with a housing to form a pre-assembled assembly, wherein said pre-assembled assembly can form a rail- or rod-shaped component which can be placed or mounted on the slotted panel or can also be mounted at a distance therefrom on a contour located behind the slotted panel, for example a ceiling.

[0042] For example, the lighting device can have a U-shaped housing, which can at least partially accommodate the elongated, extruded-profile lens between its legs and essentially completely accommodate the longitudinal shielding means and the light source arrangement. Said housing can be open toward the slotted panel. However, the slotted panel can also form the exit side of the housing or close said exit side of the housing except for an exit slot.

[0043] Irrespective of this, the slit-shaped light exit opening in the slit panel can have a contour that widens in cross-section away from the lens to avoid glare from stray light. Since the slit panel always has a certain thickness in practice, which can be several millimeters for wood or plaster panels, and even more than half a millimeter for metal panels, stray light can fall onto the walls of the longitudinal slit and potentially lead to glare. To avoid such stray light glare, the slit flanks can have a widening contour, particularly at an expansion angle that is at least as large as the constriction angle of the beam radiated by the lens through the longitudinal slit.Preferably, the slot flanks, viewed in cross-section, extend continuously without any stepped jumps or steps, with tangents applied to the continuously widening flanks all expanding at least by the aforementioned expansion angle. For example, the slot flanks, viewed in cross-section, may have a straight profile and together define a wedge-shaped or V-shaped slot contour.

[0044] Preferably, the slot contour is sharp-edged at least on its tapered side facing the lens.

[0045] The invention is explained in more detail below with reference to preferred embodiments and the accompanying drawings. In the drawings: Fig. 1: a cross section through a lighting device of an advantageous embodiment of the invention perpendicular to the longitudinal extent of the slot-shaped light exit opening of the slot panel, Fig. 2: a perspective sectional view of the lighting device from Fig. 1 , which shows the elongated, extruded profile-like design of the lens and its arrangement behind the slit panel as well as the longitudinal suppression means provided on the light entry side of the extruded profile-like lens in the form of a lens array, Fig. 3: a representation of the assignment of the elongated, extruded profile-like lens to the slit panel, wherein partial view a shows a cross-sectional view perpendicular to the longitudinal extent of the slit-shaped light exit recess and partial view b shows a perspective view, and partial view c shows a cross-sectional view similar to partial view a perpendicular to the longitudinal extent of a further embodiment in which the flanks of the longitudinal slit are widened in a wedge shape, Fig. 4: a perspective representation of the elongated, extruded profile-like lens, which according to one embodiment of the invention can be provided with a longitudinal faceting on the light exit surface, Fig.5: a representation of the lighting device from the preceding figures together with a rail-shaped housing or rail-shaped mounting support on which the light source arrangement, the longitudinal blanking means and the elongated, extruded profile-like lens can be mounted and can be combined to form a pre-assembled assembly, wherein partial view a shows a perspective exploded view before final assembly of the assembly, partial view b shows an exploded front view and partial view c shows a front view in the assembled state, Fig. 6: a front view similar. Figur 5c the pre-assembled assembly comprising housing and / or mounting rail, light source arrangement, longitudinal blanking means and elongated, extruded profile-like lens, wherein, in contrast to the embodiment according to Fig. 5c the elongated, extruded-profile lens is not mounted or attached to the assembly of the longitudinal blanking means, but rather laterally to the housing or mounting rail, wherein partial view 6a shows a housing open to the exit side for mounting under a ceiling or wall panel, and partial view b shows a design variant in which the slotted panel is attached to the housing and forms its light exit side, Fig. 7: a perspective partial view of the longitudinal blanking means in the form of two longitudinal blanking lenses in the form of freeform lenses, wherein partial view a shows the two freeform lenses themselves in perspective, partial view b shows the beam path through one of the freeform lenses in a plane "1" parallel to the longitudinal extent of the slot-shaped light exit recess of the slotted panel, and partial view c shows the beam path in a transverse plane "2" perpendicular thereto in partial view a, Fig.8: a representation of the light distributions of one of the light-shielding lenses from the preceding figures in a sectional plane perpendicular to the longitudinal direction of the slit-shaped light exit recess of the slit panel and in a transverse plane perpendicular to said longitudinal direction in comparison to one another, and Fig. 9: a comparative representation of various variants of the longitudinal shielding means and the beam paths generated thereby in sectional planes parallel to the longitudinal direction of the light exit slit of the slit panel, wherein partial view a) shows longitudinal shielding means in the form of shaders, partial view b) shows longitudinal shielding means in the form of reflectors and partial view c) shows longitudinal shielding means in the form of a lens array, wherein various design options in the form of differently contoured freeform surface lenses are shown for the lens array.

[0046] As the figures show, the lighting device 1 comprises a plurality of light sources 15 which are arranged in a row one behind the other or next to each other and together form a linear light source arrangement 2, cf. Fig. 5 . The light sources 15 can be arranged along a straight line, but possibly also along a curved or zigzag-shaped or other line.

[0047] The light sources 15 can advantageously be point-shaped light sources, in particular LEDs, whereby multi-chip LED components with several LED chips can also form a light source, for example in order to be able to mix light of different colors.

[0048] The linear light source arrangement 2 is assigned a slotted panel 5, which can advantageously form a ceiling and / or wall cladding panel and can be mounted in the manner of a pre-fabricated wall cladding or a suspended ceiling cladding. However, the slotted panel 5 can also form the exit side of a luminaire housing 20, see FIG. Figur 6b . Notwithstanding this, the said slotted panel may be flat, but may also be arched or curved.

[0049] The light source arrangement 2 is arranged on the rear side of the aforementioned slotted panel 5, i.e., between the suspended ceiling panel and the actual ceiling, or between the wall panel and the masonry wall, or between the exit panel of the luminaire housing and the rear floor of the luminaire housing. The light source arrangement 2 is thus concealed behind the slotted panel 5 or mounted concealed by the slotted panel.

[0050] In order to be able to shine the light of the light source arrangement 2 through the slotted panel 5 and to illuminate the space located on the front side of the slotted panel 5, a slot-shaped light exit opening 6 is formed in the slotted panel 5, which can form a narrow, elongated slot through which light can pass, cf. Fig. 1 and 3 .

[0051] The slit-shaped light exit opening 6 follows the arrangement of the light source 15 and can, in particular, have a straight path if the light source arrangement 5 is also linear. Alternatively, however, the slit-shaped light exit opening 6 can also have a curved or zigzag-shaped longitudinal axis.

[0052] The slit-shaped light exit opening 6 is advantageously narrow in order to make the light source arrangement behind the slit panel virtually invisible and to avoid visual contact with the light source and the associated glare. For example, the slit-shaped light exit opening 6 can have a width of only a few millimeters, for example, in the range of 5-25 mm or 10-15 mm. In any case, the length of the slit-shaped light exit opening 6 is many times greater than its width, for example, 10 times, 50 times, 100 times, or even 1,000 times as large, for example, if the lighting device is installed in a long corridor.

[0053] In order to efficiently direct the light emitted by the light source arrangement 2 through the narrow light exit slit 6, an elongated lens 4 is provided between the light source arrangement 2 and the slit panel 5, and thus on the rear side of the slit panel 5. This elongated lens 4 can extend over the entire length of the light source arrangement 2 and / or the slit-shaped light exit opening 6. In other words, the length of the lens 4 can essentially correspond to the length of the light source arrangement 2 and the length of the slit-shaped light exit opening 6, so that the length of the lens 4 is also a multiple of its width or height.

[0054] The lens 4 can in particular be formed continuously and contoured in the manner of an extruded profile, so that the lens 4 has a substantially constant cross-sectional contour and size over its entire length.

[0055] The lens 4 is designed to capture the light emitted by the light source arrangement 2 essentially completely and to emit a constricted bundle of light rays 7 from its light exit surface 16, which bundle of light rays tapers away from the light exit surface 16 of the lens 4 towards the slit panel 5, passes through the slit-shaped light exit opening 6 and widens again away from the slit panel 5, cf. Fig. 1 .

[0056] The aforementioned light beam 7 has a constriction 17 in the region of the slit-shaped light exit opening 6, which forms, so to speak, the waist of the light beam 7 or the narrowest point of the light beam 7 and has an elongated strip shape that follows or corresponds to the course of the slit-shaped light exit opening 6. In other words, the constriction 17 can form an elongated, straight strip if the light exit slit is formed straight, or it can also form a curved or zigzag-shaped longitudinal strip if the light exit slit is contoured accordingly.

[0057] How Fig. 3 shows, the lens 4 can generate a cross radiation through the slit 6, whereby the left side of the lens 4 radiates to the right and the right side of the lens 4 radiates crosswise to the left, cf. Fig. 3 . By means of the crosswise radiation, the focus of the lens 4 or the constriction 17 of the light beam 7 can be placed directly in the slit 6, whereby maximum efficiency of the system can be achieved while simultaneously controlling the resulting light distribution.

[0058] As the Figuren 1 and 3 show, the width of the lens 4 is considerably larger than the width of the light exit slit 6. If one considers the width of the light exit surface 16 of the lens 4, which in Fig. 1 and in Fig. 3(a) can be seen, in relation to the width of the constriction 17 of the light beam 7, which in Fig. 1 can be seen that the lens 4 can have a degree of constriction of approximately 1.2 to 2.5, wherein the said degree of constriction represents the ratio of the beam diameter at the light exit surface 16 of the lens 4 to the minimum beam diameter in the region of the slit-shaped light exit opening 6 of the slit panel 5, in each case in sectional planes perpendicular to the longitudinal extent of the slit-shaped light exit opening 6.

[0059] As the Figur 3c shows, the longitudinal slot 6 can advantageously have widening contoured slot flanks 6a, 6b, so that the cross section of the longitudinal slot 6 widens towards the space to be illuminated or away from the lens 4. The widening of the cross-sectional contour of the longitudinal slot 6 advantageously has an expansion angle that at least corresponds to the constriction angle of the constricted light and can possibly also be larger. The slot flanks 6a and 6b are - viewed in cross section - preferably continuously contoured and, for example, provided with a straight course, as shown in Figur 3c On the tapered side, the slot flanks 6a, 6b can be sharp-edged, cf. Figur 3c .

[0060] The elongated, extruded profile-like lens 4 can advantageously have, on its side facing the light source arrangement 2, a longitudinal groove-shaped light entry recess 12 with which the lens 4 sits above the light source arrangement 2, cf. Fig. 1 , Fig. 5 and Fig. 9 . In particular, the lens 4 with its groove-shaped light entry recess 12 can be positioned above the light source arrangement 2 in such a way that the lens 4, in particular its groove-shaped light entry recess 12, completely encloses the half-space into which the light sources 15 of the light source arrangement 2 radiate.

[0061] How Fig. 1 shows, the elongated lens 4, viewed in cross-section, can have a - roughly speaking - butterfly-shaped contour. Independently of this, the lens 4 can be designed to direct a direct light component without reflection from the light entry surface to the light exit surface 16 and to emit it from there without reflection, see reference number 7d. In addition, the lens 4 can also emit a reflected indirect light component 7i, which is initially directed from the light entry surface of the lens 4 to one of the side flanks of the lens 4 and there reflected by total reflection or by a reflective coating applied to the side flank and deflected to the light exit surface 16, in order to then be emitted from the said light exit surface 16, see reference number 7i in Fig. 1 .

[0062] The direct light component and the indirect light component 7d and 7i can be emitted with preferably essentially the same constriction and expansion angles, cf. Fig. 1 , wherein the lens 4 can in particular be designed such that the direct light and indirect light components 7d, 7i essentially completely overlap in the region of the constriction 17, cf. Fig. 1 .

[0063] How Fig. 4 As shown, the lens 4 can be provided on its light exit side 16 with a faceting, in particular longitudinal faceting, ie, facets extending parallel to the longitudinal direction L. The linear lens 4 can advantageously be manufactured using an extrusion process, e.g., an extrusion molding process, which allows for a low component price. In order to achieve better control over the light distribution, the aforementioned longitudinal faceting can be applied, cf. Fig. 4 . Through longitudinal faceting, the bundling or widening of different lens areas can be precisely controlled to achieve the highest quality in light distribution.

[0064] The elongated, extruded profile-like lens 4 can effect the described constriction of the light beam 7 only in cutting planes perpendicular to the longitudinal direction L, since the lens 4, due to its great length or its linear design, does not in itself have a light-directing effect in cutting planes parallel to the said longitudinal direction L, and light rays can also propagate very flatly through the lens and then be emitted accordingly.

[0065] In order to be able to eliminate or reduce this potential risk of glare in the longitudinal direction, as described above, a series of longitudinal masking means 8 are provided between the elongated lens 4 and the light source arrangement 2, which limit the light entering the elongated lens 4 in sectional planes parallel to the longitudinal extent L of the slit-shaped light exit opening 6 to a narrowed light beam area 9, cf. Fig. 7(b) as well as Fig. 9 . The longitudinal masking means 8 can leave the radiation characteristic of the light source 15 in transverse directions Q transverse to the longitudinal direction L or in cross-sectional planes perpendicular to the longitudinal direction L of the lens 4 essentially unaffected or leave it at a Lambertian distribution, so that the light in the said cross-sectional planes can enter the elongated lens 4 essentially diffusely and is shaped exclusively by the lens 4.

[0066] However, in the cutting planes parallel to the longitudinal direction L, the longitudinal shielding means 8 can define a narrowed light beam range 9 of, for example, 2x 25° to 2x 55° or 2x 35° to 2x 50° relative to the main beam direction 10. The main beam direction 10 can be the main beam direction of the light sources 15 and, for example, be perpendicular to the slotted panel 5.

[0067] Fig. 8 shows the direction-dependent or different influence of the longitudinal masking means 8 on the light distribution of the light beam entering the elongated lens 4, wherein the light distribution curve marked as "bundled" represents the light distribution in a sectional plane parallel to the longitudinal direction L, while the light distribution curve marked as "diffuse" represents the light distribution in a sectional plane perpendicular to the longitudinal direction L.

[0068] The aforementioned longitudinal blanking means 8 can advantageously be designed in the form of longitudinal blanking lenses 11, which can be arranged between the light sources 15 and the elongated lens 4. Preferably, the longitudinal blanking lenses 11 can be arranged in the groove-shaped light entry recess 12 of the elongated lens 4, cf. Fig. 5 .

[0069] How Fig. 5(a) As illustrated, a plurality of longitudinal blanking lenses 11 can be arranged one behind the other or next to each other and form a linear lens array, the course of which can correspond to the course of the slit-shaped exit opening 6, that is to say can be straight, for example.

[0070] Advantageously, the longitudinal blanking lenses 11 can be combined to form a common lens module, for example in the form of a lens band, which can have one or two mounting wings that can extend next to the actual, optically active lenses 11, cf. Fig. 5 .

[0071] For example, the lens array mentioned can be designed like a flat, elongated plate in which the longitudinal blanking lenses 11 can bulge in a central section, so that the longitudinal blanking lenses 11 are enclosed on the right and left by strip-shaped mounting plates. All longitudinal recess lenses 11 or groups of longitudinal recess lenses 11 can be combined in one piece and connected to the strip-shaped mounting plates.

[0072] How Fig. 5 shows, the lens array of the longitudinal suppression lenses 11 can also be coupled to the lens 4. For example, positive coupling and / or fastening means 18 can be provided on the longitudinal suppression lenses 11 and / or the lens 4, for example in the form of plug-in flanges 19, which can protrude from the lateral wings of the lens array on the one hand and from the side flanks and / or the light entry side of the elongated lens 4 on the other hand, cf. Fig. 5(a) und 5(b) Such positive-locking fastening means 18 between the elongated lens 4 and the longitudinal blanking lenses 11 allow their relative position to be precisely determined. At the same time, joint assembly of the lens 4 and the longitudinal blanking lenses 11 can be simplified.

[0073] How Fig. 5 shows, the lens 4 can be pre-assembled together with the longitudinal blanking means 8 and also the light source arrangement 2 to form a common assembly, in particular together with a mounting rail 20, which can, for example, have a U-shaped cross-section and / or form a housing enclosing the optical components. As Fig. 5 As shown, for example, the lens array and an LED board located underneath, on which the light sources 15 are formed, can be screwed to the bottom of the U-shaped housing. The lens 4 is held to the lens array by the fastening means 18.

[0074] How Fig. 6 shows, the elongated lens 4 can also be mounted or fastened separately from the longitudinal masking means 8, for example in the region of its light exit surface 16 on the U-rail-shaped housing 20, cf. Fig. 6a . Furthermore, Figur 6b shows, the U-rail-shaped housing 20 can also be used to fasten the slotted panel 5 directly to the luminaire housing 20, for example to the side legs of the luminaire housing 20 by means of a sliding guide or in another way.

[0075] The longitudinal blanking lenses 11 mentioned can basically be designed in different ways. Fig. 5 , 7 and 9 As illustrated in FIG. 1, the longitudinal aperture lenses 11 can advantageously be free-form surface lenses that focus the light in the longitudinal direction L and can maintain the diffuse radiation of the light sources 15 in the transverse direction Q. For example, the longitudinal aperture lenses 11 can be bridge-arch-shaped lens modules that are open on opposite sides, namely in the transverse direction Q, cf. Fig. 7(a) , which focus the light in cutting planes parallel to the longitudinal direction L, cf. Fig. 7(b) , while in transverse directions Q, ie in cutting planes perpendicular to the longitudinal direction L, it can remain a Lambertian distribution, cf. Fig. 7(c) .

[0076] However, the longitudinal blanking means 9 can also be designed differently, as Fig. 9 clarified.

[0077] For example, the longitudinal masking means 8 can have shading devices 21, cf. Fig. 9(a) , for example in the form of black SMD components or other absorbing shielding parts, which can be arranged in the longitudinal direction directly next to the light sources 15 and extend in the transverse direction Q in order to shade or mask out flat rays of the light sources 15 in cutting planes parallel to the longitudinal direction L, cf. Fig. 9(a) .

[0078] Alternatively or additionally, the longitudinal masking means 8 can also have reflectors 14, cf. Fig. 9(b) , which can also be assigned to each of the light sources 15, for example can enclose the light sources 15 on opposite sides in the form of a half-shell in order to deflect and bundle the light rays emitted by the light sources 15 in sectional planes parallel to the longitudinal direction L, cf. Fig. 9(b) .

Claims

1. Lighting device with a slit panel (5) with at least one slit-shaped light exit opening (6), an elongated light source arrangement (2) and an elongated, extruded profile-like lens (4), wherein the light source arrangement (2) and the lens (4) are arranged in a concealed manner behind the slit panel (5) and extend along the slit-shaped light exit opening (6), and the lens (4) is designed to emit a constricted light beam (7) which tapers away from the lens (4) towards the slit panel (5), passes through the slit-shaped light exit opening (6) and widens again away from the slit panel (5), characterized in thatbetween the light source arrangement (2) and the lens (4) a series of optical longitudinal masking means (8) for limiting the light rays in the light beam bundle (7) in sectional planes parallel to the longitudinal extent (L) of the slit-shaped light exit opening (6) to a narrowed light beam region (9) are provided.

2. Lighting device according to the preceding claim, wherein the row of longitudinal masking means (8) is designed to leave the light beam (7) unaffected transversely (Q) to the longitudinal extent (L) of the slit-shaped light exit opening (6) and provides a restriction of the radiation area essentially only in sectional planes parallel to the longitudinal extent (L) of the slit-shaped light exit opening (6).

3. Lighting device according to one of the preceding claims, wherein the row of longitudinal blanking means (8) in the sectional planes parallel to the longitudinal extent (L) of the slit-shaped light exit opening (6) limits the narrowed light beam range (9) to 2 x 70° or less, or to 2 x 60° or less, or to 2 x 45° or less around the main emission direction (10), preferably to a narrowed light beam range (9) of 2 x 25° to 2 x 55° or 2 x 35° to 2 x 50° to said main beam direction (10).

4. Lighting device according to the preceding claim, wherein said main radiation direction (10) extends perpendicular to the slotted panel (5).

5. Lighting device according to one of the preceding claims, wherein the row of longitudinal blanking means (8) comprises a row of longitudinal blanking lenses (11) which are lined up along the longitudinal extent (L) of the slit-shaped light exit opening (6) and are arranged between the light source arrangement (2) and the elongated, extruded profile-like lens (4).

6. Lighting device according to the preceding claim, wherein the light source arrangement (2) comprises a series of point-shaped light sources (15), in particular in the form of LEDs, and each point-shaped light source is assigned a longitudinal blanking lens (11).

7. Lighting device according to one of the two preceding claims, wherein the longitudinal blanking lenses (11) are designed to capture the light emitted by the light source arrangement (2) as a whole substantially completely and to radiate it completely onto the elongated, extruded profile-like lens (4).

8. Lighting device according to one of claims 5 to 7, wherein the longitudinal blanking lenses (11) form an interconnected, in particular integrally formed, lens array and / or each form free-form lenses which bundle light received from the light source arrangement (2) in the longitudinal direction (L) and provide diffuse radiation in the transverse direction (Q).

9. Lighting device according to one of the preceding claims, wherein the extruded profile-like lens (4) has a groove-shaped, elongated light entry recess (12) with which the lens (4) sits above the light source arrangement (2), wherein the row of longitudinal blanking means (8) are at least partially received in said groove-shaped light entry recess (12) of the lens (4) and / or the lens (4) with said groove-shaped light entry recess (12) is slipped over the longitudinal blanking means (8).

10. Lighting device according to one of the preceding claims, wherein the elongated, extruded profile-like lens (4) has a degree of constriction of approximately 1.2 to 2.5, wherein said degree of constriction represents the ratio of the beam diameter at the light exit surface of the lens (4) to the minimum beam diameter in the region of the slit-shaped light exit opening (6) of the slit panel (5), in each case in sectional planes perpendicular to the longitudinal extent of the slit-shaped light exit opening (6).

11. Lighting device according to one of the preceding claims, wherein the longitudinal masking means (8) and the lens (4) are designed to substantially completely capture the light emitted by the light source arrangement (2) and to direct it through the slit-shaped light exit opening (6).

12. Lighting device according to one of the preceding claims, wherein the elongated, extruded profile-like lens (4) has opposite side flanks (13) which are designed to be totally reflective and / or have a reflective coating, wherein light rays reflected from one of the side flanks (13) intersect with light rays reflected at the other of the two side flanks (13) in the region of the slit-shaped light exit opening (6).

13. Lighting device according to one of the preceding claims, wherein the elongated, extruded profile-like lens (4) is designed to emit an unreflected direct light component (7d) passing centrally through the lens (4) and an indirect light component (7i) reflected on side flanks (13) of the lens (4), wherein the said direct light and indirect light components (7d, 7i) have substantially the same radiation angles and each substantially completely fill the beam bundle (7) emitted by the lens (4).

14. Lighting device according to one of the preceding claims, wherein the row of longitudinal blanking means (8) comprises a row of reflectors (14) which are lined up along the longitudinal extent (L) of the slit-shaped light exit opening (6) and reflect a part of the light coming from the light source arrangement (2) and radiate it in a deflected manner into the elongated, extruded profile-like lens (4).

15. Lighting device according to one of the preceding claims, wherein the row of longitudinal shielding means (8) comprises a row of shaders (21) or black absorber elements which are lined up along the longitudinal extent (L) of the slit-shaped light exit opening (6) and shade or absorb part of the light coming from the light source arrangement (2).

16. Lighting device according to one of the preceding claims, wherein the light beam bundle (7) emerging from the slit-shaped light exit opening (6) is formed in sectional planes transverse to the longitudinal extent (L) of the slit-shaped light exit opening (6) substantially exclusively by the elongated, extruded profile-like lens (4) and is formed in sectional planes parallel to the longitudinal extent (L) of the slit-shaped light exit opening (6) substantially exclusively by the longitudinal masking means (8).

17. Lighting device according to one of the preceding claims, wherein the longitudinal blanking means (8) are arranged separately and / or spaced apart from both the light source arrangement (2) and the elongated lens (4).

18. Lighting device according to one of the preceding claims, wherein the slit-shaped light exit opening (6) of the slit panel (5) has, when viewed in cross-section, widening slit flanks (6a, 6b), so that the slit width increases towards the space to be illuminated, wherein said slit flanks (6a, 6b) widen at an widening angle which is at least as large as the constriction angle of the light constricted by the lens (4), wherein said slit flanks (6a, 6b) extend continuously when viewed in cross-section and tangents applied to the slit flanks (6a, 6b) all widen at least by the said widening angle, wherein the slit flanks (6a, 6b) are preferably formed with sharp edges on the tapered side facing the lens (4).

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