Improved luminaire

Abstract

A luminaire (1) comprises LEDs (2) that are arranged on or in a substrate (3) and configured to emit LED light (60). Optical components (4) are arranged on the substrate (3). Each optical component (4) is configured to collimate LED light (60) emitted by a respective LED into collimated light (61). A louver (5) comprises a cap (51) and two side shields (56, 57) arranged perpendicular to the cap; the louver (5) is configured to direct the collimated light (61) into directed light (62) exiting the louver (5). The optical components (4) are configured to collimate the LED light by TIR into the collimated light having a gamma (y) angle with respect to a normal direction (32) to the first major surface (31) of the substrate (3) in an interval 25° to 40°. The cap (51) of the louver (5) is arranged at a main louver angle (52) with respect to the normal direction (32), the main louver angle (52) being equal to or less than the y angle.

Description

[0001] 2024PF80468

[0002] 1

[0003] IMPROVED LUMINAIRE

[0004] FIELD OF THE INVENTION

[0005] The present invention generally relates to a luminaire. More specifically, the present invention is related to a luminaire comprising a plurality of light emitting diodes, (LED), collimating total internal reflection (TIR) optical components and a louver configured to direct collimated light into directed light.

[0006] BACKGROUND OF THE INVENTION

[0007] In sports lighting, it is important to achieve high maximum intensity of the light emitted by a luminaire. It is also important that luminaires used in such a context provide a sharp decrease of the light output, i.e. so-called “cutoff’, in upward directions in order to reduce unwanted light pollution.

[0008] Prior art sports lighting luminaires that are based on a combination of LEDs and TIR optical components typically have weak cutoff characteristics. (Contrary, in luminaires with reflectors, cutoff comes naturally). Therefore, prior art sports lighting luminaires are typically configured with very large louvers and are therefore typically both heavy and unwieldy, particularly when used in a context where the sports lighting luminaires are to be mounted, dismounted and moved between different sports arenas.

[0009] SUMMARY OF THE INVENTION

[0010] It is thus of interest to provide a luminaire that is capable of overcoming drawbacks of prior art devices.

[0011] This and other objects are achieved in a first aspect by providing a luminaire having the features of the appended independent claim. Preferred embodiments are defined in the appended dependent claims.

[0012] Hence, according to the present invention there is provided a luminaire comprising a plurality of LEDs that are arranged on a first major surface of, or in, a substrate and configured to emit LED light. A plurality of optical components are arranged on the first major surface of the substrate. Each optical component is configured to collimate LED light 2024PF80468

[0013] 2 emitted by a respective LED into collimated light. In various embodiments, the optical components may form part of a lens plate.

[0014] The expression “collimate” is to be understood herein as “to narrow a light beam”. Consequently, the term “collimated light” is to be understood as meaning a beam of light comprising parallel rays while also comprising at least some light that has a certain amount of divergence, as long as it is narrower than the LED light emitted by the LEDs prior to being subject to TIR within the optical components.

[0015] The luminaire further comprises a louver that comprises a cap and two side shields arranged perpendicular to the cap. The louver is configured to direct the collimated light into directed light exiting the louver.

[0016] The optical components are configured to collimate the LED light by TIR into the collimated light having a collimation direction towards the cap. In other words, the collimated light is directed away from the normal of the first major surface of the substrate in the direction of the cap of the louver.

[0017] Additionally, the optical components are configured to collimate the LED light by TIR into the collimated light having a gamma (y) angle with respect to a normal direction to the first major surface of the substrate in an interval 25° to 40°. Furthermore, the cap of the louver is arranged at a main louver angle with respect to the normal direction, the main louver angle being equal to or less than the y angle.

[0018] In such a luminaire, being configured with a relationship between the y angle of the collimated LED light and the angle of the louver cap, the apparent light emitting surface as viewed from the direction of maximum intensity is small, i.e. smaller than from a perspective perpendicular to the first major surface of the substrate, and thus allows a shorter louver to achieve the same cutoff characteristics as a prior art luminaire having a longer louver.

[0019] The louver may comprise an inner surface configured to provide specular reflection of the collimated light.

[0020] In various embodiments, the louver comprises at least one vertical lamella arranged perpendicular to the cap and arranged parallel to and between the side shields and comprising a surface configured to provide specular reflection of stray light hat has been totally internally reflected by the optical components into y angles outside the interval 25° to 40°. 2024PF80468

[0021] 3

[0022] Such a configuration has an effect of spreading some light to the sides, creating a visual effect to an observer as if the entire luminaire is “wider”, while the reflected light from the vertical lamellas is also cut by the virtual image of the main louver cap.

[0023] In various embodiments the louver comprises at least one vertical lamella arranged perpendicular to the cap and arranged parallel to and between the side shields and comprising a surface configured to absorb stray light that has been totally internally reflected by the optical components into y angles outside the interval 25° to 40°.

[0024] Such a configuration has an effect of preventing spread of light to the sides. That is, such embodiments provide a narrow spread of light creating a visual effect to an observer as if the entire light engine is “narrow”.

[0025] In various embodiments, the louver comprises at least one sagittal lamella arranged perpendicular to the side shields and comprising a surface configured to absorb stray light that has been totally internally reflected by the optical components into y angles outside the interval 25° to 40°.

[0026] In another aspect there is provided a floodlight system comprising at least one luminaire as summarized above. Such a floodlight system provides effects and advantages that correspond to those summarized above in connection with the luminaire.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment(s) of the invention where: figure la schematically illustrates a perspective view of a luminaire, figure lb schematically illustrates a CO plane and a C90 plane associated with the luminaire in figure la, figure 1c schematically illustrates a cross-section view of the luminaire in figure la, figure Id schematically illustrates a cross-section view of part of the luminaire in figure la, figure 2a schematically illustrates a perspective view of a luminaire, figure 2b schematically illustrates a cross-section view of the luminaire in figure 2a, figure 3a schematically illustrates a side view of a floodlight system, and figure 3b schematically illustrates a front view of a floodlight system. 2024PF80468

[0029] 4

[0030] DETAILED DESCRIPTION

[0031] As illustrated in figures la, lb, 1c and Id, an embodiment of a luminaire 1 may comprise a plurality of LEDs 2 arranged on a first major surface 31 of a substrate 3 and configured to emit LED light 60. The LEDs 2 may in some embodiments be arranged in the substrate 3.

[0032] A plurality of optical components 4 are arranged on the first major surface 31 of the substrate 3, each optical component 4 being configured to collimate LED light 60 emitted by a respective LED 2 into collimated light 61. For example, the optical components 4 may form part of a lens plate. An interface 7 between the LED 2 and the optical component 4 comprises a cape part 8 and a negative lens part 9. LED light 60 entering into the optical component 4 via the cape part 8 and the negative lens part 9 is projected onto TIR sides 10 of the optical component 4. The negative lens part 9 is simply configured such that it collimates the LED light 60.

[0033] A louver 5 comprises a cap 51 and two side shields 56, 57 arranged perpendicular to the cap 51, the louver 5 being configured to direct the collimated light 61 into directed light 62 exiting the louver 5. For example, the louver 5 may have one or more inner surfaces configured to provide specular reflection of the collimated light 61.

[0034] The optical components 4 are configured to collimate the LED light 60 by total internal reflection into the collimated light 61 having a collimation direction towards the cap 51. In other words, the collimated light 61 is directed away from the normal direction 32 of the first major surface 31 of the substrate 3 in the direction of the cap 51 of the louver 5.

[0035] The optical components 4 are additionally configured to collimate the LED light 60 by total internal reflection into the collimated light 61 having a gamma, y, angle with respect to a normal direction 32 to the first major surface 31 of the substrate 3 in an interval 25° to 40°. The cap 51 is arranged at a main louver angle 52 with respect to the normal direction 32, the main louver angle 52 being equal to or less than the y angle.

[0036] By such a configuration of the cap 51, a reduction of light going upward (i.e. direction indicated with z in figures la and 1c). This may be expressed as the main louver angle 52 being the angle on the C90 plane comprising the maximum intensity (Imax), at which, e.g., 1% of Imax and / or <1 [cd / klm] relative luminous flux is reached. If Imax is on the C90 plane at y =35°, then the louver configuration having relative spatial dimensions as exemplified herein achieves 1% of Imax by y = 35+5 = 40° and less than 1 [cd / klm] by y=45°. This is further illustrated in figure 3a where a light ray 64 shows a light path that exits the luminaire 1 at the highest angle 641 with respect to the cap 51 where luminous intensity 2024PF80468

[0037] 5 is still directly derived of the optical components 4. Any spatial luminous intensity above this limit angle is an effect of multiple reflections of stray light within the louver 5 and thus has much lower intensity, as exemplified by light ray 63.

[0038] Turning to figures 2a and 2b, and with continued reference to figures la-d, the louver 5 may comprises at least one vertical lamella 53 arranged perpendicular to the cap 51 and arranged parallel to and between the side shields 56, 57 and comprising a surface configured to provide specular reflection of stray light 70 that has been totally internally reflected by the optical components 4 into y angles outside the interval 25° to 40°. In some embodiments, such a vertical lamella 53 may comprise a surface configured to absorb stray light 70 that has been totally internally reflected by the optical components 4 into y angles outside the interval 25° to 40°.

[0039] Continuing with reference to figures 2a and 2b, in some embodiments, the louver 5 may comprise at least one sagittal lamella 54 arranged perpendicular to the side shields 56, 57 and comprising a surface configured to absorb stray light 71 that has been totally internally reflected by the optical components 4 into y angles outside the interval 25° to 40°.

[0040] As illustrated in figure 3a and 3b, a floodlight system 300 may comprising at least one luminaire 1 as described herein. For example, three luminaires 1 may be arranged on a tall post 310 and thereby enable illumination at a sports event 350.

Claims

2024PF804686CLAIMS1. A luminaire ( 1 ) compri sing : a plurality of light emitting diodes, LEDs, (2) arranged on a first major surface (31) of, or in, a substrate (3) and configured to emit LED light (60), a plurality of optical components (4) arranged on the first major surface (31) of the substrate (3), each optical component (4) being configured to collimate LED light (60) emitted by a respective LED (2) into collimated light (61), a louver (5) comprising a cap (51) and two side shields (56, 57) arranged perpendicular to the cap (51), the louver (5) being configured to direct the collimated light (61) into directed light (62) exiting the louver (5), wherein: the optical components (4) are configured to collimate the LED light (60) by total internal reflection into the collimated light (61) having a collimation direction towards the cap (51) and having a gamma, y, angle with respect to a normal direction (32) to the first major surface (31) of the substrate (3) in an interval 25° to 40°, and the cap (51) is arranged at a main louver angle (52) with respect to the normal direction (32), the main louver angle (52) being equal to or less than the y angle.

2. The luminaire (1) according to claim 1, wherein: the louver (5) comprises an inner surface configured to provide specular reflection of the collimated light (61).

3. The luminaire (1) according to any one of the preceding claims, wherein: the louver (5) comprises at least one vertical lamella (53) arranged perpendicular to the cap (51) and arranged parallel to and between the side shields (56, 57) and comprising a surface configured to provide specular reflection of stray light (70) that has been totally internally reflected by the optical components (4) into y angles outside the interval 25° to 40°.2024PF8046874. The luminaire (1) according to any one of the preceding claims, wherein: the louver (5) comprises at least one vertical lamella (53) arranged perpendicular to the cap (51) and arranged parallel to and between the side shields (56, 57) and comprising a surface configured to absorb stray light (70) that has been totally internally reflected by the optical components (4) into y angles outside the interval 25° to 40°.

5. The luminaire (1) according to any one of the preceding claims, wherein: the louver (5) comprises at least one sagittal lamella (54) arranged perpendicular to the side shields (56, 57) and comprising a surface configured to absorb stray light (71) that has been totally internally reflected by the optical components (4) into y angles outside the interval 25° to 40°.

6. The luminaire (1) according to any one of the preceding claims, wherein the optical components (4) form part of a lens plate.

7. A floodlight system (300) comprising at least one luminaire (1) according to any one of claims 1 to 6.

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