Lighting configuration

Abstract

The lighting configuration includes a cup with walls defining a light output aperture, and multiple LED light sources arranged within the cup. The lighting configuration further includes multiple lenses, each positioned adjacent to its respective LED light source and positioned to direct the LED light emitted by its respective LED light source through the light output aperture of the cup. The multiple lenses are arranged on a lens plate, with walls positioned to protrude from the lens plate, and each lens is separated from each other by sections of the walls.

Description

Technical Field

[0001] The present invention generally relates to lighting configurations. More specifically, the present invention relates to a lighting configuration for providing downward overhead illumination and a lighting fixture including such a lighting configuration.

Background Art

[0002] Lighting fixtures for illuminating environments such as offices should provide an appropriate luminous flux and intensity distribution to give a sufficient illuminance level (e.g., an average of 300 lux, E max / E average <2 uniformity) on the work surface. At the same time, the Unified Glare Rating (UGR) must not exceed the specified target. In the United States, UGR < 22 is the achievement standard (norm), and in Europe, the specification is often UGR < 19.

[0003] There is a strong desire to reduce energy consumption and reduce material use, not only from the perspective of sustainability but also from the perspective of overall cost reduction. Energy consumption can be reduced by increasing the efficacy of the lighting fixture or by increasing the efficiency of providing task illuminance (i.e., bringing light to the required locations). Reduction of material use and overall cost can be achieved by reducing the number of lighting fixtures required to illuminate the environment, i.e., by increasing the luminaire spacing indoors. Standard luminaire spacing ranges from 1.80 to 3.0 meters in Europe and 8 to 10 feet in the United States and is typically restricted by glare requirements, uniformity requirements, and task illuminance requirements.

[0004] Thus, as luminaire spacing increases, the luminous flux per luminaire must be increased to meet the work surface illumination requirements. Furthermore, to achieve the uniformity requirement when luminaire spacing increases, each luminaire needs to have a wider beam to cover this wider area. However, both higher luminous flux and wider beams risk negatively impacting glare perception and increasing UGR to an unacceptable level. Conventional luminaires have been found unable to meet these illuminance, uniformity, and UGR requirements when luminaire spacing exceeds 3 meters. [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In light of the disadvantages associated with the prior art, the object of the present invention is to provide a configuration that enables the provision of uniform high illumination in the environment while simultaneously enabling low UGR (Ultraviolet Growth Rate). [Means for solving the problem]

[0006] The object of the present invention is achieved by a lighting arrangement for providing downward overhead illumination. The lighting arrangement includes a cup with walls defining a light output aperture, and a plurality of LED light sources arranged within the cup. The lighting arrangement further includes a plurality of lenses, each lens positioned adjacent to its respective LED light source and arranged to direct the LED light emitted by its respective LED light source through the light output aperture of the directional cup. The plurality of lenses are arranged on a lens plate, with walls positioned to protrude from the lens plate, and each lens is separated from each other by a section of the wall. The walls may have optical properties that cause changes in the direction of the LED light through reflection, refraction, or scattering. The walls of the cup may be white, and in various embodiments, the light output aperture of the cup may have a contour that is circular, elliptical, oval, polygonal, leaf-shaped, or a combination thereof.

[0007] The lens plate, multiple lenses, and wall may be a single integral unit.

[0008] Each lens may protrude from the lens plate by a lens height, and the wall may protrude from the lens plate by a maximum wall height, the maximum wall height being less than or equal to the lens height. Alternatively, the maximum wall height may be greater than or equal to the lens height.

[0009] The number of LEDs in the plurality of LED light sources may be 2 to 9, the number of lenses in the plurality of lenses may be 2 to 9, and the pitch between each LED may be 1 to 4 times the width of each LED.

[0010] In other words, the lighting configuration may include clusters or arrays of LEDs. This is advantageous when there are constraints on LED placement due to a string configuration. By placing additional optical elements in the form of walls between the lenses, it is possible to reduce asymmetry in the visibility cutoff of the bright lenses, light up the area between the lenses, and reduce the contrast between the lenses, thereby improving viewer comfort.

[0011] At least one lens may be configured to direct LED light according to at least one C-plane intensity profile. Each C-plane intensity profile includes a primary intensity peak in a first gamma (γ) angle interval between γ1 and γ2, where γ2 is greater than γ1, and each C-plane intensity profile includes a secondary intensity shoulder or peak in a second γ angle interval between γ3 and γ4 at an intensity lower than the primary intensity peak, where γ3 is greater than γ2, γ4 is greater than γ3, and γ4 is 180° or less. The first γ angle interval may be between γ1=0°, preferably 20°, more preferably 30° and γ2=55°, preferably 50°, and the second γ angle interval may be between γ3=60° and γ4=90°, preferably 80°. The cup walls may be white, and in various embodiments, the light output aperture of the cup may have a contour that is circular, elliptical, oval, polygonal, leaf-shaped, or a combination thereof.

[0012] The lighting configuration may be such that LED light directed by at least one lens at a first γ-angle interval exits the light output aperture of the cup without hitting the walls of the cup, and LED light directed by at least one lens at a second γ-angle interval hits the walls of the cup before exiting the light output aperture of the cup.

[0013] At least one lens may include a base portion and a top portion, the top portion being configured to direct LED light to a first γ angular interval, and the base portion being configured to direct LED light to a second γ angular interval.

[0014] Alternatively, at least one lens may include a base portion and a top portion, the top portion configured to direct LED light to a second γ angular interval, and the base portion configured to direct LED light to a first γ angular interval.

[0015] In other words, such an LED-based lighting configuration provides peak intensity at a γ angle between γ1 and γ2. For an observer positioned below the lighting configuration, the visibility of the bright lens is cut off by the cup wall surrounding the lens, and the LED (or lens) is not visible at γ angles greater than the cutoff angle. The value of the cutoff angle depends on the actual design of the lens and cup and the arrangement of the LED and lens within the cup. The lens is designed so that the intensity of the bare lens increases or at least shows a discontinuity at γ angles greater than the cutoff angle, and gives a second (but smaller) intensity peak or intensity shoulder at a γ angle between γ3 and γ4. Some of the light intercepted by the cup wall is re-emitted, adding a small Lambertian contribution to the overall intensity distribution from the lighting configuration. This ensures that the luminance of the cup wall is high enough so that the entire surface area of ​​the cup is taken into account in the UGR calculation specified by the International Commission on Illumination (CIE), thereby contributing to a low UGR. It should be noted that commercially available optical engineering software tools such as "LightTools" can be used to design the parameters and relationships of lenses and cups that produce the desired intensity profile.

[0016] The object of the present invention is achieved by a lighting fixture comprising a plurality of lighting configurations summarized above, which have the effects and advantages summarized above. [Brief explanation of the drawing]

[0017] Herein, this and other aspects of the present invention will be described in more detail with reference to the accompanying drawings illustrating (multiple) embodiments of the present invention. [Figure 1] Figure 1a schematically shows a perspective view of a lighting configuration that forms part of a lighting fixture, Figure 1b schematically shows a cross-sectional view of a lighting configuration having one LED and one lens, Figure 1c schematically shows the intensity profile, and Figure 1d schematically shows a side view of the lens. [Figure 2] Figure 2a schematically shows a cross-sectional view of a lighting configuration having multiple LEDs and lenses, Figure 2b is a detailed view of the lighting configuration schematically shown in Figure 2a, and Figures 2c and 2d schematically show perspective views of the lighting configuration having multiple LEDs and lenses. [Figure 3] A schematic side view of a lighting fixture that provides downward overhead illumination is shown. [Modes for carrying out the invention]

[0018] Referring to Figures 1a-1d and Figure 3, the lighting configuration 100 for providing downward overhead illumination includes a cup 101 with a wall 102 defining a light output aperture 103. At least one LED light source 104 is positioned on a printed circuit board (PCB) within the cup 101, and at least one lens 105 is positioned adjacent to the LED light source 104 and is arranged to direct the LED light 106 emitted by the LED light source 104 through the light output aperture 103 of the cup 101.

[0019] At least one lens 105 is configured to direct the LED light 106 according to at least one C-plane intensity profile 130a, 130b. Such two intensity profiles 130a, 130b are illustrated in the diagram of FIG. 1c. Each C-plane intensity profile 130a, 130b includes a main intensity peak 131 at a first gamma (γ) angular interval between γ1 and γ2, where γ2 is greater than γ1. Each C-plane intensity profile 130a, 130b includes a secondary intensity shoulder or peak 132 at a second γ angular interval between γ3 and γ4, at an intensity lower than the intensity of the main intensity peak 131, where γ3 is greater than γ2, γ4 is greater than γ3, and γ4 is 180° or less.

[0020] As shown in FIGS. 1a and 1b, the γ angle is the angle of the LED light emission from the lens 105 with respect to the main light direction 110, which is the downward direction in the context of this specification. The γ angle can have a value between 0° and 180°. The C-plane is defined such that the main light direction 110 lies in the C-plane, and the C-plane can have a rotation angle of 0° to 360° centered on the main light direction 110.

[0021] The LED light 106 directed by at least one lens 105 at the first γ angular interval exits the light output aperture 103 of the cup 101 without hitting the wall 102 of the cup 101. The LED light 106 directed by at least one lens 105 at the second γ angular interval hits the wall 102 of the cup 101 before exiting the light output aperture 103 of the cup 101. In FIG. 1b, this is indicated by the cut-off γ angle 1ll.

[0022] The first γ angular interval is between γ1 = 0°, preferably 20°, more preferably 30° and γ2 = 55°, preferably 50°, and the second γ angular interval is between γ3 = 60° and γ4 = 90°, preferably 80°.

[0023] Figure 1d shows that at least one lens 105 can include a base portion 121 and a top portion 122. The top portion 122 is configured to direct LED light 106, emitted by the LED 104, at a first gamma angular interval, and the base portion 121 is configured to direct the LED light 106 at a second gamma angular interval. Area 123 shows the area of the surface of the base portion 121 where most light is directed at the second gamma interval.

[0024] Note that the base portion 121 and the top portion 122 may partially overlap such that less than 100% of the light passing through one portion ends up in the corresponding gamma interval.

[0025] In fact, it is also possible to obtain a top portion 122 that directs light at a second gamma angular interval and a base portion 121 that directs light at a first gamma angular interval by configuring at least one lens 105 with total internal reflection (TIR). In such a design, the light rays traversing the base portion 121 and the light rays traversing the top portion 122 intersect. That is, in such a configuration, the top portion 122 is configured to direct the LED light 106 at a second gamma angular interval, and the base portion 121 is configured to direct the LED light 106 at a first gamma angular interval.

[0026] Referring here to Figures 2a-2d, the lighting configuration 200 for providing downward overhead illumination includes a cup 201 with a wall 202 defining a light output aperture 203, and a plurality of LED light sources 204 may be arranged on a printed circuit board (PCB) 212 within the cup 201. The lighting configuration 200 further includes a plurality of lenses 205, each lens 205 positioned adjacent to its respective LED light source 204 and positioned to direct the LED light 206 emitted by each LED light source 204 through the light output aperture 203 of the directional cup 201. The plurality of lenses 205 are arranged on a lens plate 221, with a wall 207 positioned to protrude from the lens plate 221, and each lens 205 is positioned to be separated from each other by a section of the wall 207.

[0027] The wall 207 has optical properties that cause a change in the direction of the LED light 206 through reflection, refraction, or scattering.

[0028] Figure 2a shows two cutoff γ angles 211 and 212 for different parts of the cup wall 202, illustrating how the wall 207 intercepts the LED light 206 emitted through the lens 205, which is located at different distances from the cup wall 202 along different γ angles for different parts of the cup wall 202, thereby preventing direct view of the lens 205 by the viewer 310.

[0029] As shown in the detailed view of the lighting configuration 200 in Figure 2b, each lens 205 protrudes from the lens plate 221 by a lens height of 241, and the wall 207 protrudes from the lens plate 221 by a maximum wall height of 242.

[0030] As shown in Figure 2c, the maximum wall height 242 may be less than or equal to the lens height 241, and as shown in Figure 2d, the maximum wall height 242 may be greater than or equal to the lens height 241.

[0031] The wall 207 shown in Figures 2c and 2d has a varying height. In particular, the wall 207 has a top side with multiple projections or protrusions.

[0032] In the examples of Figures 2c and 2d, the wall 207 has a topside with a sawtooth profile, which is an example of a serrated (or toothed) profile. A sawtooth profile is a periodically repeating non-sinusoidal profile characterized by a linear, rising edge and a sudden drop-off.

[0033] As described above, the sawtooth profile of the wall 207 shown in Figures 2c and 2d is an example of a serrated profile, and a serrated profile is an example of multiple protrusions or projections. Alternatively, other serrated profiles may be used, such as other multiple protrusions or projections, e.g., regular or irregular, non-sinusoidal or sinusoidal profiles. As described above, the wall 207 is positioned to intercept the LED light 206 emitted through the lens 205, which is located at different distances from the cup wall 202 along different γ angles with respect to different parts of the cup wall 202. This positions the wall 207 to prevent direct viewing of the lens 205.

[0034] The wall 207 may be made of the same material as the lens 205, in which case the wall 207 is made of an optically clear material, that is, a material that absorbs, reflects, and scatters little to no light. Such a material may also be called a transparent material.

[0035] If the wall 207 is made of a material that absorbs, reflects, and scatters little or no light, direct viewing through the lens 205 may be obscured, for example, by scattering through the surface texture, but this may have only a limited effect.

[0036] Alternatively, direct viewing through lens 205 can be obstructed by surface structures, which can have a stronger effect, especially if such surface structures produce a total internal reflection (TIR) ​​effect.

[0037] If the wall 207 is positioned relatively close to the lens 205, there may not be enough space on the side of the wall 207 (i.e., the surface facing the lens 205) to provide a light deflection structure. In such a situation, the top side of the wall 207 is still available for providing a desired light deflection structure in the form of a surface structure, such as a surface structure that is positioned to deflect light by the TIR effect.

[0038] By providing multiple protrusions or projections on the top side of the wall 207 in the form of serrated (or tooth-shaped) profiles, such as the sawtooth profiles shown in Figures 2c and 2d, the wall 207 is positioned to obstruct direct viewing of the lens 205 through scattering via the surface structure. Furthermore, if the wall 207 is made of an optically clear material, the surface structure formed by the multiple protrusions or projections may produce a TIR effect to further enhance the ability to obstruct direct viewing of the lens 205.

[0039] The wall 207 may have a thickness (for example, a thickness in the range of 0.5 to 5 millimeters, such as a range of 1 to 3 millimeters) such that only a small portion of the light rays (light rays that enter the side of the wall 207 at a specific angle of incidence and a specific height) reach the top side and undergo a change of direction.

[0040] A further advantage of the wall 207 having a top side with multiple protrusions or projections is that rays from a wider range of incident angles and positions that enter the side of the wall 207 can reach the top side and then be deflected.

[0041] Multiple projections or protrusions provided on the top side of wall 207 have amplitude and spacing, wherein the amplitude is the height of the projection or protrusion (or the average height if the projection or protrusion has an inconsistent height), and the spacing is the distance between adjacent projections or protrusions (or the average spacing if the projections or protrusions are separated by an inconsistent distance).

[0042] The amplitude and / or spacing of the multiple protrusions or projections are preferably smaller than the dimensions of lens 205, such as on the order of 5 to 50% of the dimensions of lens 205.

[0043] As illustrated in the perspective view of Figure 2d, the lens plate 221, the multiple lenses 205, and the wall 207 may be a single integrated unit 222, but Figure 2c illustrates a configuration in which the lenses 205 and the wall 207 are separate entities placed on the lens plate 221.

[0044] Figures 2c and 2d illustrate a lighting configuration comprising four lenses 205 and four corresponding LEDs 204. However, in other embodiments, the number of LEDs 204 in a plurality of LED light sources 204 may be 2 to 9, the number of lenses 205 in a plurality of lenses 205 may be 2 to 9, and the pitch 232 between each LED 204 may be 1 to 4 times the width 231 of each LED 204, as shown in Figure 2b.

[0045] Similar to the embodiment of the lighting configuration 100 described in relation to Figures 1a-1d, in the lighting configuration 200 illustrated in Figures 2a-2d, at least one lens 205 may be configured to direct the LED light 206 according to at least one C-plane intensity profile 130a, 130b, as shown in Figure 1c. Each C-plane intensity profile 130a, 130b includes a principal intensity peak 131 in a first gamma (γ) angular interval between γ1 and γ2, where γ2 is greater than γ1, and each C-plane intensity profile 130a, 130b includes a secondary intensity shoulder or peak 132 in a second γ angular interval between γ3 and γ4 at an intensity lower than the principal intensity peak 131, where γ3 is greater than γ2, γ4 is greater than γ3, and γ4 is 180° or less.

[0046] LED light 206 directed by at least one lens 205 at a first γ-angle interval exits the light output aperture 203 of the cup 201 without hitting the wall 202 of the cup 201. LED light 206 directed by at least one lens 205 at a second γ-angle interval hits the wall 202 of the cup 201 before exiting the light output aperture 203 of the cup 201. In Figure 2a, this is indicated by the cutoff γ angle 211.

[0047] The first γ angular interval is between γ1=0°, preferably 20°, more preferably 30° and γ2=55°, preferably 50°, and the second γ angular interval is between γ3=60° and γ4=90°, preferably 80°.

[0048] At least one lens 205 may correspond to the lens 105 shown in Figure 1d, and therefore may include a base portion 121 and a top portion 122. The top portion 122 is configured to direct the LED light 106 emitted by the LED 104 at a first γ angular interval, and the base portion 121 is configured to direct the LED light 106 at a second γ angular interval. Area 123 indicates an area of ​​the surface of the base portion 121 where most of the light is directed at a second gamma interval.

[0049] It should be noted that the base portion 121 and the top portion 122 may partially overlap such that less than 100% of the light passing through one portion ends up in the corresponding gamma interval.

[0050] In fact, by configuring at least one lens 105 using total internal reflection (TIR), it is also possible to obtain a top portion 122 that directs light to a second γ angular interval and a base portion 122 that directs light to a first γ angular interval. In such a design, light rays traversing the base portion 121 and light rays traversing the top portion 122 intersect. That is, in such a configuration, the top portion 122 is configured to direct the LED light 106 to a second γ angular interval, and the base portion 121 is configured to direct the LED light 106 to a first γ angular interval.

[0051] The lighting configurations 100 and 200 illustrated above may also have cups 101 and 201 with white walls 102 and 202. Furthermore, the light output apertures 103 and 203 of the cups 101 and 201 may have contours that are circular, elliptical, oval, polygonal, leaf-shaped, or a combination thereof.

[0052] As shown in Figure 3 and Figure 1a, the lighting fixtures 150 and 300 may include multiple of the lighting configurations 100 and 200 described above.

Claims

1. A lighting configuration for providing downward overhead illumination, the lighting configuration is: A cup including a wall that defines the light output aperture, Multiple light-emitting diode (LED) light sources are arranged inside the cup, Multiple lenses, each lens positioned adjacent to its respective LED light source, and arranged to direct the LED light emitted by its respective LED light source through the light output aperture of the cup, A lens plate on which the aforementioned plurality of lenses are arranged, A wall positioned to protrude from the lens plate, wherein each lens is positioned so as to be separated from each other by a section of the wall, Includes, The aforementioned wall has optical properties that cause a change in the direction of LED light through reflection, refraction, or scattering. The aforementioned wall is a lighting configuration having a top side with multiple protrusions or projections.

2. The lighting configuration according to claim 1, wherein the plurality of protrusions or projections form a serrated profile.

3. The lighting configuration according to claim 1 or 2, wherein the plurality of protrusions or projections provided on the top side of the wall have amplitude and spacing, and the amplitude and / or spacing is smaller than the dimensions of the lens.

4. Each lens protrudes from the lens plate by a lens height, The aforementioned wall protrudes from the lens plate to a maximum wall height, The lighting configuration according to any one of claims 1 to 3, wherein the maximum wall height is less than or equal to the lens height.

5. Each lens protrudes from the lens plate by a lens height, The aforementioned wall protrudes from the lens plate to a maximum wall height, The lighting configuration according to any one of claims 1 to 3, wherein the maximum wall height is equal to or greater than the lens height.

6. The lighting configuration according to any one of claims 1 to 5, wherein the lens plate, the plurality of lenses, and the wall are a single integrated unit.

7. The number of LEDs in the aforementioned plurality of LED light sources is 2 to 9. The number of lenses in the aforementioned plurality of lenses is 2 to 9. The lighting configuration according to any one of claims 1 to 6, wherein the pitch between each LED is 1 to 4 times the width of each LED.

8. At least one lens is configured to direct LED light according to at least one C-plane intensity profile, Each C-surface intensity profile is γ １ and gamma ２ The first gamma (γ) angle interval between and includes the main intensity peak, γ ２ is γ １ Larger than, Each C-plane intensity profile includes a secondary intensity shoulder or peak at an intensity lower than the intensity of the main intensity peak at a second γ angular interval between γ ３ and γ ４ where γ ３ is greater than γ ２ and γ ４ is greater than γ ３ and γ ４ is 180° or less, the lighting configuration according to any one of claims 1 to 7.

9. The lighting configuration is, The LED light, directed by the at least one lens at the first γ angular interval, exits the light output aperture of the cup without hitting the wall of the cup, and The LED light, directed by the at least one lens at the second γ angular interval, strikes the wall of the cup before leaving the light output aperture of the cup. The lighting configuration according to claim 8, configured as described above.

10. The at least one lens includes a base portion and a top portion, The top portion is configured to direct the LED light to the first γ angular interval, The lighting configuration according to claim 8 or 9, wherein the base portion is configured to direct LED light to the second γ angular interval.

11. The at least one lens includes a base portion and a top portion, The top portion is configured to direct the LED light to the second γ angular interval, The lighting configuration according to claim 8 or 9, wherein the base portion is configured to direct LED light to the first γ angular interval.

12. The first γ angular interval is γ １ = 0° and γ ２ = Between 55°, The second γ angular interval is γ ３ = 60° and γ ４ The lighting configuration according to any one of claims 8 to 11, wherein the angle is between 90° and 0°.

13. The lighting configuration according to any one of claims 1 to 12, wherein the wall of the cup is white.

14. The light output aperture of the cup is Circle, ellipse, oval, polygon, Leaf shape, or Any of the above combinations, A lighting configuration according to any one of claims 1 to 12, having a contour that is the shape of the above.

15. A lighting fixture comprising a plurality of lighting configurations described in any one of claims 1 to 14.

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