Illumination system device and illumination system
The lighting device addresses space and energy inefficiencies in shop window lighting by using fixed, oriented lighting units to project transverse light patches, enabling dynamic and energy-efficient illumination.
Patent Information
- Application Number
- JP2020572488
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2018-06-25
- Filing Date
- 2019-06-20
- Publication Date
- 2025-09-25
- Estimated Expiration
- 2039-06-20
AI Technical Summary
Existing lighting systems for shop windows are cumbersome, require ladders for installation, lack dynamic lighting effects, and often consume excessive energy due to static lighting solutions, with limited space and visibility issues hindering effective scene creation.
A lighting device comprising an elongated carrier with fixed, oriented lighting units projecting light patches in transverse directions, allowing for dynamic lighting effects and energy-efficient illumination patterns without the need for extensive beam widening, using LEDs and adjustable beam angles to create uniform and appealing lighting scenes.
The solution provides a compact, energy-efficient, and visually appealing lighting system that overcomes space constraints, allows for dynamic lighting effects, and optimizes heat distribution, reducing the risk of accidents and energy waste.
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present invention relates to a lighting device and a lighting system. [Background technology]
[0002] It is known that setting up the lighting of shop window scenes using known lighting devices and lighting systems is often considered a hassle for the visual merchandisers and store personnel who have to decorate and light them, which usually entails a number of disadvantages.
[0003] (1) Because most of the space is taken up by the models and products on display, show windows often have limited space, so standing in a show window can be risky, and even a slight mistake in movement can disrupt the whole scene.
[0004] (2) Another disadvantage is that the spots for shop window lighting are usually installed high up, beyond arm's reach, which means that a ladder is needed to aim the spot, again with the risk of cluttering the scene and of it tipping over and injuring shop staff.
[0005] (3) In addition to the limited space, it is not possible to judge the lighting (modeling) results (play of light and shadow) as a result of the spot positioning and aiming, because the person doing this is too close to the scene to see the visual end result as it would be seen from the road. For best results, you need to stand outside in front of the shop window and have someone direct you to perfectly position and aim the spots to get the lighting scene the way you want it.
[0006] (4) There is also the issue of over- or under-illuminating a scene. During the day, high-intensity light needs to be directed at the scene to reduce the diffuse reflections caused by daylight (reflected from opposing surfaces) on window glass. This is usually done by using a high-intensity narrow beam spot to increase the brightness of the display. However, there are large differences in lighting levels depending on the time of day, season, and weather. Therefore, lighting levels are usually implemented to work under the most difficult lighting conditions (hence high daylight levels measured on a clear summer day at noon). This often results in the display being over-lit (when daylight conditions are low) and consuming a lot of energy. At night, this is not necessary, and only a small amount of light can create a more balanced and beautiful lighting scene, improving presentation quality and saving energy at the same time. In practice, the same lighting solution is often used 24 / 7.
[0007] Note that similar systems can be used in stores for walls and other staging setups, and the discussion here is largely the same (space, ladders, and positions to view the scene from a distance to see lighting effects).
[0008] (5) Most current solutions for shop windows are static. Research has shown that the human eye is very sensitive to both brightness and motion. Usually, it is not possible to create a scene with moving light unless a moving spot is used. This can only be done with programmable motorized spot products. For example, track lighting devices with pan, zoom, tilt, and multiple motors for moving the lamp along the track are known. The disadvantage is that dynamic (mechanically moving) products are more sensitive to breakdowns and maintenance than static products.
[0009] (6) For a more realistic, natural, and appealing effect, it is preferable to use two spots with different color temperatures and beam angles (aimed from different positions). Skylight, like in a daylight outdoor situation, diffused by clouds is usually directionless and cooler than directional sunlight. To mimic this effect, narrow beam spots with a lower color temperature (appearing warmer) are often used from one side (experts call these spots key lights, which mimic the directional sunbeam), and wide beam spots with a higher color temperature (appearing cooler) are often used from the other side to fill in the shadows (which have too much contrast). It is usually preferable to position the key and fill lights at a 45° horizontal angle and a 30° vertical angle, so-called key / fill light spots, on opposite sides of each other. Many window staging professionals are unaware of these effects, and the wide variety of spots available often means they are out of stock in stores.
[0010] (7) In addition to the key and fill light spots, it is also good to add a backlight effect. In practice, this is not usually done.
[0011] (8) Pin or uplight spots may also be used in conjunction with backlighting. These are spots that are usually installed at the bottom front of a shop window. They are usually narrower beam spots used to highlight special details or to create theatrical lighting effects from below. In practice, this is not usually done.
[0012] WO2013134646A1 discloses an illumination device including an array of illumination units extending in a first direction, the array of illumination units projecting an array of light patches extending in the same first direction. Summary of the Invention [Problem to be solved by the invention]
[0013] SUMMARY OF THE INVENTION It is an object of the present invention to alleviate at least one of the above-mentioned disadvantages of known lighting devices or known lighting systems. [Means for solving the problem]
[0014] For this reason, the present invention discloses a lighting device as defined in claim 1. Typically, the lighting device comprises an elongated carrier having a length and a first plurality of lighting units mounted on the carrier and extending only in a first direction of the elongated carrier, each lighting unit of the first plurality of lighting units being mounted in a respective, fixed, predetermined orientation, the first plurality of lighting units being configured to directly project a first plurality of light patches (e.g., onto a target surface P facing, typically extending in the first direction and a second direction transverse to the first direction, the lighting device being offset from the target surface P in a third direction different from these directions), the first plurality of light patches extending at least in a second direction different from the first direction, and the lighting device being offset from the surface P in a third direction different from the first and second directions.
[0015] In summary, the row of first lighting units and the row of first light patches projected by them as spots extend primarily transverse to one another, and these spots are mutually aimed and positioned to merge into a line or two-dimensional area of light without the need to widen the beam of each lighting unit by scattering / diffusion means, for example, by frosted light exit windows of each lighting unit. Conversely, it is preferable to have a narrow spot that allows tuning of the illuminated area with high resolution. This is a different way of illuminating a line or area than that done by fluorescent tubes or TLEDs, which provide floodlight illumination without distinguishable spots.
[0016] The expression "transverse direction" in the present invention is intended to mean a second direction having an angle Δ with respect to the first direction, for example 75°<=Δ<=105°, preferably 85°<=Δ<=95°, for example Δ=90°. A first plurality of lighting patches are, for example, projected onto an opposing target surface P extending typically in the first direction and a second direction transverse to the first direction, and the lighting device may be offset from the setting surface P in a third direction different from these directions. Typically, the first lighting units are arranged consecutively, and when all first lighting units are in switch-on mode, the patches in the row of first light patches are also arranged consecutively.
[0017] One embodiment of this illumination pattern may be that the first plurality of light patches extend only in a second direction transverse to the first direction, i.e. the number of light patches in the second direction is equal to the number of first plurality of light patches generated by the lighting device, and the number of light patches in the first direction is only one (or zero). This embodiment is intended to include at least the following two configurations:
[0018] - the light pattern may be a single line in which the light patches of the first plurality of lighting units and the further light patches of the further plurality of lighting units are adjacent to each other only in the second direction, i.e. the further light patches are on the extension of the first plurality of light patches in the second direction.
[0019] - the light pattern may be a two-dimensional (2D) pattern in which light patches of the first plurality of lighting units and further light patches of the further plurality of lighting units are projected as rows (each row extending only in the second direction), with at least some rows being projected adjacent to one another in the first direction. In other words, there is also at least some repetition of the rows of light patches that extend also in the first direction, i.e. the further plurality of light patches are an extension of the first plurality of light patches at least in the first direction and optionally also in the second direction.
[0020] The lighting device may be characterized in that the first direction, the second direction, and the third direction are the X, Y, and Z directions of a Cartesian coordinate system, respectively. In this case, the lighting device includes a plurality of first lighting units (e.g., unit rows) mounted in a first direction on an elongated carrier, each lighting unit mounted in a respective fixed, unique, predetermined orientation and configured to generate a unique light beam having a beam angle and a fixed, unique orientation for generating a unique light patch on a target surface P, the lighting device configured to directly project the plurality of light patches (e.g., patch rows) onto the target surface P, the surface P extending in the first direction X and in a second direction Y transverse to the first direction, the plurality of light patches extending in the second direction, and the lighting device offset from the surface P in a third direction Z. The lighting device may be in an oblique position with respect to the (imaginary) surface P. Furthermore, the lighting device may have at least one of the following characteristics: each lighting unit has a unique fixed, predetermined orientation; and each lighting unit has a fixed beam angle. Since most shop windows can be viewed as three-dimensional rectangular boxes, the first direction, second direction, and third direction can be most easily defined by a Cartesian XYZ coordinate system, thus simplifying computer modeling and computer processing / control of the shop window illumination pattern. Thus, the lighting device may have the characteristic that the pre-oriented array of lighting units is linear and extends along either the X, Y, or Z direction so as to easily fit into the Cartesian XYZ coordinate system.
[0021] In the context of the present invention, the following should be understood.
[0022] - Essentially, each lighting unit comprises a light source and respective associated optical components, the light source being preferably one or more LEDs. Optionally, multiple lighting units can generate different beam angles and color temperatures to enhance the lighting scene by the so-called McCandless method, as also used in theatrical stage lighting.
[0023] - fixed, uniquely oriented, pre-determined means that there are no pairs of optical axes of the lighting units that run parallel.
[0024] - directly means without the use of (distant) additional optical components such as mirrors, reflectors, lenses, deflectors, etc.
[0025] - Rows do not have to be straight, they can be curved.
[0026] The lighting device disclosed according to the present invention as defined in the independent claims and further as defined in the dependent claims alleviates at least one, but in fact most or all, of the disadvantages mentioned above.
[0027] A first important feature of the lighting device of the present invention is the miniaturization of the hardware, i.e., the miniaturization of the device used to illuminate the shop window. Essentially, all lighting units of the lighting device have LEDs as light sources embedded in slim carriers, e.g., bars, with a cross-sectional diameter of at most a few centimeters, typically 3-5 cm, and lengths typically ranging from 15 cm to 180 cm, often in 60 cm unit lengths or multiples thereof (since these are the unit lengths typically used for ceiling tiles in suspended ceilings). This miniaturization is achieved by (1) breaking up the small number of large spots of the prior art into a line or matrix lighting device with multiple lighting units for generating multiple beamlets, and (2) directing the projected beamlets of the lighting units per lighting device along a line rather than an extensive matrix (requiring relatively small lighting units and, consequently, small beam-shaping optics).
[0028] The lighting device may have the following feature: the lighting device includes at least one further plurality of lighting units extending only in the first direction, the at least one further plurality of lighting units configured to directly project further light patches to form an integral light pattern combined with the first plurality of light patches projected by the first plurality of lighting units. The lighting device may have the following feature: the further plurality of light patches are projected parallel to and adjacent to the first plurality of light patches in the first direction. The lighting device may have the following feature: the at least one further plurality of lighting units is in an extension of the first plurality of lighting units. The lighting device may have the following feature: a second plurality of lighting units or second and third plurality of lighting units of the at least one further plurality of lighting units are arranged parallel to and adjacent to the first plurality of lighting units.
[0029] Instead of the lighting units being arranged in a single line, the first and second lighting units may be arranged in an XY matrix, with the number of lighting units in the X direction (or first direction) being much greater than the number of rows positioned parallel to one another in the Y direction (or second direction). When referring generally to lighting units, this may include first, second, and / or further lighting units. Similar references apply to rows or light patches, i.e., this may include rows of first, second, and / or further light patches. Typically, the number of parallel rows of first and second lighting units (in the Y direction) is 1-3, with the lighting device having a width in the range of about 2 cm-8 cm, while the number of lighting units per lighting device in the first direction (or X direction) is a minimum of 5 or 7, or typically, for example, about 20-60 lighting units per lighting device, with the lighting device having a length in the range of about 15 cm-200 cm. This results in an aspect ratio Rld of the lighting device, ie length divided by width, in the range 3<=Rld<=100.
[0030] An advantage of the translation of multiple lighting units extending in the X direction and multiple light patches projected by them extending in the Y direction transverse to the X direction is the possibility of increasing the number of light patches extending in the Y direction compared to the number of parallel rows arranged in the Y direction, and / or improving the distribution of the (local) heat load of the lighting device or system. Visualize the situation of a vertical surface being uniformly illuminated by multiple parallel rows of lighting devices positioned vertically above the vertical surface and offset in the Z direction. When each row of lighting devices projects a corresponding row of light patches extending in the same direction, the row of lighting units located closest to the corresponding portion of the illuminated vertical surface is operated at a relatively dim level, while the row of lighting units located farthest from the corresponding portion of the illuminated vertical surface is operated at a relatively boosted level. This results in an uneven, localized, undesirable high heat load of the lighting device or system, whereas in the lighting device or system of the present invention, the heat load is evenly distributed because the closest and furthest parts of the illuminated surface are illuminated by the same lighting unit of the same lighting device.
[0031] Preferably, for the desired accent lighting of objects in the shop window, the beams are typically aimed at an angle of approximately 45° relative to the horizontal, X-direction, and approximately 45° to 60° relative to the vertical, Y-direction. However, due to limited space within the shop window, not all positions in the target area can be reached from such angles. For example, if all beams were aimed 45° to the right, the left corner of the target area of the shop window would be dark. Therefore, preferably, the beam direction changes with the position of the lighting unit (or spot). Thus, the light beams emitted from the lighting device are aimed so that the entire vertical surface within the shop window is more or less uniformly illuminated by a rectangular matrix of light patches, called spots or pixels (for key / fill light spots). The total number of first and second lighting units is individually positioned and directed to provide light patches in specific areas. The arrangement may be a square matrix, but a hexagonal spot layout or any other tiling of light patches is also possible. However, at least the light patches include, as a subset of the light patches, a first row of light patches extending transversely to the direction of the first lighting unit projecting said row of light patches. Preferably, the light patches include at least one second (or further) row of light patches substantially parallel to the first row, so that the patched light pattern can form a continuous / closed illumination pattern on a target area, typically in a (vertical) plane, for example, when the target area is located at an average distance of at least 1 meter from the lighting device. Typically, for shop window illumination, the distance between the lighting device and the target area is in the range of 2 m to 4 m.
[0032] A simulation of an embodiment of the present invention was performed with satisfactory results. In the simulation, a 3-m-wide shop window was illuminated by a lighting bar with 140 small beams covering an area 2.1 m high and 3 m wide. The vertical spacing of the spot patches was 30 cm (7 spots per column) and the horizontal spacing was 15 cm (20 spots per row). Each beam was generated by a high-power LED with an output of 200-400 lm in combination with beam-shaping optics (e.g., a 10 mm diameter TIR lens) to produce a beam with a FWHM of approximately 10-12° for narrow spots and a width of typically 30-40° for wide beam spots. The aiming direction in the vertical plane was determined by the spots illuminating the mannequin's head and chest (preferably, the vertical angle was in the range of 45-60°). Higher and lower spot rows may deviate from this rule. The beam angle in the horizontal plane varies linearly between 0° for the left row of spot patches and 45° for the right row of spot patches. Of course, this variation can be concentrated in the left portion of the bar (e.g., the first meter) so that the angle can be constant at 45° for the right portion of the bar. In a modular approach, the bar can be composed of a left segment with a linearly varying angle and any number of segments with a constant angle to accommodate shop windows of different widths. In this way, the potential problem of dark corners in a shop window is solved, for example, if all key lights are at a 45° horizontal angle. If the window is wide, this is only a transition area, and the largest part of the window can be illuminated with all key lights at 45°. Therefore, in a modular approach, the corner pieces have a varying horizontal angle and the regular pieces have a fixed angle.
[0033] Because the lighting device is small in two dimensions and long in only one dimension, its visual impact (obscuring, distracting) on the viewer is very limited. Thus, even when placed at an optimal height for illuminating merchandise, e.g., 2 to 2.5 meters above the floor, it is possible to form an unobtrusive lighting device along the shop window when multiple lighting devices are combined so that they are substantially aligned in a horizontal direction along the horizontal length of the shop window (the vertical direction is the direction of gravity). This is advantageous over conventional solutions that require positioning a bulky spot on the ceiling (typically 3.5 meters above the floor) to avoid the distracting visual impact of the spot.
[0034] However, to facilitate understanding of the present invention, the following example is provided: In shop window lighting, typically, the vertical height of the target area to be illuminated ranges from 1 m to 3 m, which means that each lighting device, approximately 30 cm long and including approximately 10 lighting units, should illuminate the full vertical height of up to approximately 3 m with key lighting (for fill lighting, the number of lighting units may be different, i.e., less, for example, half or a quarter of the number of key lighting units). The distance between the lighting units located at both ends of the lighting device (in this case, approximately 30 cm) should be enlarged to provide projected light spots spaced approximately 3 m apart, and each lighting unit should provide a projected spot with a diameter preferably of approximately 30 cm to provide the desired continuous / closed lighting pattern in the target area. This can be achieved by a lighting device in which each lighting unit is mounted in its own fixed, unique, predetermined orientation. For ease of handling of lighting units, it is convenient for a lighting device to be a relatively small entity containing a limited number of lighting units and used to generate only a single row of light patches on a target area. By using rows of various lighting devices side by side, multiple rows of light patches can be generated adjacent to each other on a target area. Thus, a target area with a vertical height of 3 m and a horizontal width of n * 30 cm can be fully and continuously illuminated (and thus without unlit dark holes or optical gaps) by a lighting system containing n lighting devices side by side. (This typically applies to key lighting; for fill lighting, the size of the light patches may be different, i.e., larger, e.g., approximately 60 cm to 100 cm in diameter.) By turning on and off the desired lighting units of the lighting device / lighting system, a desired light pattern on the complete (2D) target area can be obtained. However, such a 2D pattern can also be obtained by a single large lighting device. Although the light patch diameter and the light patch pitch are linked, they do not necessarily have to be the same.If the radius is much larger than the pitch, there will simply be more overlap between adjacent spots. The radius should not be too small, as this will result in gaps (dark areas) in the illumination pattern in the target area.
[0035] The applications of the lighting device and lighting system of the present invention are not limited to shop window illumination, but are also suitable for other applications, such as display areas within shops, horizontal surfaces, street lighting, facade lighting, museum lighting, wall washing, etc.
[0036] An alternative way of describing more or less the same or similar invention is as follows:
[0037] - an illumination device comprising a row of lighting units mounted in a first direction on an elongated carrier, each lighting unit being mounted in a respective, fixed, unique, predetermined orientation, said row of lighting units of the illumination device being configured to directly project (onto a target plane P) a row of light patches extending in a second direction Y substantially transverse to / angled with the first direction, wherein no single plane can be identified in which both the row of lighting units and the row of light patches extend.
[0038] - an illumination device comprising an array of lighting units mounted in a first direction on an elongated carrier, each lighting unit being mounted with a respective fixed, unique, predetermined orientation of its respective optical axis, the illumination device being configured to emit an array of light beams of each said array of lighting units, the array of light beams being collectively rotated in a spiral and directly projected as a line of light patches (on a plane P) extending in a second direction Y transverse to / angled with the first direction, enabled by said fixed, unique, predetermined orientation.
[0039] - an illumination device comprising an array of lighting units extending in a first direction and fixedly mounted on an elongated carrier, each lighting unit designed to emit a respective light beam along a respective fixed, uniquely oriented, predetermined optical axis, said array of lighting units of the illumination device being configured to emit said array of light beams, which, enabled by the fixed, unique, predetermined orientation, are together rotated in a spiral and directly projected as a line of light patches extending in a second direction (on a plane P) that is inclined with respect to the first direction.
[0040] - an illumination device comprising a plurality of lighting units mounted in a first direction on an elongated carrier, each lighting unit being mounted in a respective, fixed, predetermined orientation, the illumination device being configured to directly project (onto an opposing target surface P) a plurality of light patches, the plurality of light patches extending in at least a second direction different from the first direction (and the illumination device being offset from the surface P in a third direction different from the first and second directions).
[0041] In the context of the present invention, helically rotated is meant to include both screw axes where the translation axis and the rotation axis are coincident, as well as where the translation axis and the rotation axis are not coincident, and sloped means at an angle of at least 45°.
[0042] The lighting device may be characterized in that the respective solid beam angles of each light unit are such that all light patches have substantially the same shape. Preferably, all light patches also have substantially the same size. Thus, the design of a desired illumination pattern is simplified. The lighting device may be characterized in that the solid beam angles are related to the angle α between the respective optical axes and the normal to the tilted target area (surface). Typically, the following relationship applies to generate a circular spot on the tilted surface: tanβ1=D*cosα / (2*L+D*sinα) tanβ2=D*cosα / (2*LD*sinα) where β1 and β2 relate to the beam width angles of the half beam portions on either side of the optical axis of the lighting unit for the part of the inclined surface of the target area far from the lighting unit and the part of the inclined surface close to the lighting unit, respectively.
[0043] In this way, the light patches or spot sizes of the multiple lighting units projected onto the target area are rendered to be approximately the same circular shape and / or size as each other.
[0044] The lighting device may be characterized in that the carrier is rigid, i.e., does not essentially deform under its own weight, and thus mounting of the lighting device is simplified as it is relatively easy to aim the beam at the target area and / or no separate mounting structure / carrier is required.
[0045] The lighting device may be characterized in that, when viewed in a projection along a first direction, the fixed orientation of the lighting units is such that essentially a single quadrant is illuminated. The first lighting units have respective first optical axes, and further lighting units of the plurality of lighting units have respective further optical axes, with the minimum angle θ between the optical axes of the lighting units in the projected view along the first direction being in the range of 0° to 90°, e.g., 10° to 80°, or 25° to 70°, e.g., 55°. Note that the two intersecting axes bracket the minimum and maximum angles, and the minimum angle is referred to here. Typically, the lighting device / lighting system is slightly vertically offset from the target area (defined with respect to the direction of gravity), positioned approximately 1 m in front of the target area, i.e., shifted approximately 1 m forward in the Z direction, and the optical axes of the light beams emitted by the lighting device and aimed at the target area, which need to cover the full vertical height of the target area, are typically at a mutual angle within the range of 10° to 80°. The lighting device may have a feature in which the sequence of the first lighting units has a different patch sequence, e.g., an interspersed or interdigitated configuration, among the first plurality of light patches in the patched light pattern. In this context, a different sequence means that there is no detectable order of projected adjacent light patches generated in the same order by adjacent lighting units in the lighting device. The row positions of the lighting units do not necessarily correspond to the row positions of the spot pixels / patches and can be selected arbitrarily. Thus, the positions of the lighting units within the bar can be optimized, for example, to distribute thermal load, and while the generated light patches may still be adjacent to each other to form a closed pattern in the projected 2D pattern, they may not be positioned adjacent to each other. Alternatively, the lighting device may have a feature in which the sequence of the lighting units has the same patch sequence in the patched light pattern, making the lighting device intuitive and easy to control.In this context, the same sequence means that there is the same ordering of adjacent light patches to be (detectably) projected that are generated by adjacent lighting units in a lighting device having an ordering.
[0046] The lighting device may be characterized in that the lighting unit is configured to generate a beam with an adjustable solid beam angle. Methods for said adjustment are well known in the art. Thus, the light patch / spot size projected on the target area can be adjusted as needed and / or desired. Typically, the spot size has a diameter D, which can be varied by varying the distance between the lighting unit and the target area and the solid beam angle. The spot size D is related to the beam angle β and the distance L between the light source / lighting unit and the target area according to the following equation: D=2*L*tanβ Thus, the vertical spot angle β varies with distance L according to tan β=D / 2L.
[0047] In this way, the light patches or spot sizes of the multiple lighting units projected onto the target area are rendered to be approximately the same size as each other.
[0048] The lighting device may be characterized in that the beams generated by the lighting units each have an elliptical shape, the ellipse having a major diameter and a minor diameter, the major diameter of each ellipse extending in a direction perpendicular to the direction of incidence on the target area, such that the patch or spot size formed by the beams on the target area is essentially circular. The diagonal of the light patch on the target surface becomes an expanded diagonal in a plane spanned by the normal to the target surface and the direction of the incident beam when the direction of incidence is not parallel to the normal to the target surface. Therefore, the spot diagonal perpendicular to this expanded diagonal should be increased in the beams emitted from the lighting device so that a substantially circular light patch is obtained when the beams impinge on the target area (as will be explained in more detail with respect to FIGS. 8A-B ).
[0049] The lighting device may be characterized in that each patch in the array of light patches has substantially the same (peak) illuminance over the target area. In this context, substantially the same means that the ratio of the highest illuminance to the lowest illuminance is between 0.5 and 2. Generally, a factor of 2 difference in illuminance is not observable by the human eye, and therefore the illuminance is considered uniform. A uniform illuminance can be easily achieved by measuring the illuminance over the target area and then individually adjusting the power, and therefore the light output, of each lighting unit.
[0050] A first rough mathematical relationship for achieving a first preliminary setting of the various lighting units is as follows: I → (2 * L * tan α) 2 (or in other words, I → D2) where α is the angle between each optical axis and the plane of the tilted target area, α is typically in the range of 5° to 85°, and L is the distance between each lighting unit and the target area. Thus, approximately the same beam intensity (lux) is obtained at each position in the target area, resulting in a relatively uniform illumination level in the target area. Optionally, the beam intensity of each lighting device is independently controllable and adjustable for further optimization of the desired illumination pattern in the target area.
[0051] The lighting device may be characterized in that the plurality of lighting units comprises between 10 and 3000 lighting units per meter, preferably between 25 and 300, more preferably between 30 and 50. A more refined desired light pattern of light patches on a target area with higher resolution is obtained with an increased number of lighting units, which requires a number of at least 3 or 5, more preferably at least 10 (which is suitable for street lighting, for example). However, too many lighting units risks overcomplicating the control / handling of the lighting device, and thus the upper limit is preferably limited to a maximum of several thousand. A convenient number of lighting units is in the range of 25 to 300, while for simplicity and good resolution, the number is in the range of 30 to 60.
[0052] The lighting device may be characterized in that the aspect ratio AR of the light pattern covered by the array of light patches is in the range of 3<=AR<=50. Typically, for shop window illumination, the vertical height and width of the target area to be illuminated by a single lighting device is 2-3 m by about 0.2 m-0.4 m, which corresponds to an aspect ratio AR in the range of 5-15.
[0053] The lighting device may essentially be characterized in that each of the lighting units includes at least one associated LED, the at least one associated LED including a different color, color temperature, and / or CCT. This increases the versatility of the lighting device in providing desired lighting patterns. For each lighting unit, the color, color temperature, and / or correlated color temperature (CCT) of the lighting unit may be fixed or adjustable. In particular, if adjustable, at least one light source of the lighting unit includes two or more LEDs, each light source being individually controllable.
[0054] The present invention further relates to a lighting system comprising at least a first lighting device according to the present invention and at least one further lighting device substantially aligned with one another in the longitudinal direction, preferably wherein the number Nld of further lighting devices is 1<=Nld<=100, more preferably 2<=Nld<=60, and even more preferably 5<=Nld<=25. In this regard, "aligned" means that the lighting devices extend parallel to one another and / or extend as a continuous row of lighting devices. Shop windows have a wide range of horizontal widths, i.e., the width can range from less than 1 m to more than 10 m (while shop windows typically have heights ranging from about 2 m to about 4 m). Depending on the horizontal size of the shop window and the degree of overlap of patches / light spots (e.g., if key and fill light are desired for specific locations in the target area), the number of lighting devices may range, for example, from as few as 2 to 100, to completely provide the desired illumination pattern in the target area. To this end, the lighting system may have the feature that the patched light patterns of the first lighting device and the at least one further lighting device form a mutually matching / closed illumination pattern, i.e. an illumination pattern that forms a unitary, continuously illuminated sub-area on the target area without being interrupted by further sub-areas not illuminated by the lighting device.
[0055] The lighting system may be characterized in that it includes at least two parallel lighting devices extending next to each other in a first direction. The lighting system may further be characterized in that the light sources of the first lighting device and at least one second (or further) lighting device are positioned in a staggered configuration (in this regard, "staggered configuration" means "arranged in a zigzag configuration alternating along the length direction") and / or are shiftable relative to each other in the first (or length) direction / have an adjustable overlap. The number of parallel extending strips should be kept relatively small, for example, at most three, so that the lighting system has relatively small dimensions in cross section and thus remains relatively unobtrusive. Alternatively, the lighting system may be characterized in that two rows of light sources are included in a single lighting device, and the light sources of the first lighting device and the second lighting device are positioned in a staggered configuration and / or are shiftable relative to each other in the length direction / have an adjustable overlap. In this way, multiple spots generated by any of the alternatives can be targeted to the same portion of the target area, thus providing, for example, key light and fill light to said same portion. Alternatively or additionally, the first lighting device may have a first light source of a first color, color temperature, or CCT, and the second lighting device may have a second light source of a second color, color temperature (Tc), or CCT different from the first light source. Furthermore, alternatively or additionally, the lighting system may have the feature that the first light source functions as a key light and is configured to provide light at a first illuminance level, and the second light source functions as a fill light and is configured to provide light at a second illuminance level lower than the first illuminance level. All of these features contribute to the versatility and possible applications of the lighting system of the present invention.In this regard, expressions such as lower illuminance and higher illuminance may, but do not necessarily, mean that the total luminous flux emitted by the second light source is lower and higher, respectively, than the total luminous flux emitted by the first light source, but rather that the luminous intensity, expressed in candela, i.e., lumens / sr, is lower and higher, respectively, and / or lux, i.e., lumens / m. 2 are intended to represent lower and higher illumination intensities in the target area represented by
[0056] The beam widths of the key light and the fill light may be the same, but in this case, it should be considered that the illuminance on the target area of the fill light should be lower than the illuminance on the target area of the key light. Furthermore, a lighting system including a tunable lighting device allows for switching between light sources, i.e., when the same beam width is used for the key light and the fill light, a key light coming from the right and a fill light coming from the left can be easily switched between each other. Such switching can be easily performed, for example, in terms of color, Tc, CCT, illuminance, or flux.
[0057] The lighting system may be characterized in that the first light source is configured to increase the intensity of the first light as the intensity of ambient light increases and decrease the intensity of the first light as the intensity of ambient light decreases, and the second light source is configured to decrease the intensity of the second light as the intensity of ambient light increases and increase the intensity of the second light as the intensity of ambient light decreases. In other words, the intensity of the key light and the intensity of the fill light are inversely dependent on the intensity of ambient light. This allows the lighting system to adapt the scene setting to be displayed to the actual ambient conditions. In particular, when the ambient light level is relatively high, the key light is boosted to a level higher than the ambient light level to maintain its stand-out function of attracting attention and / or highlighting desired features in the scene. Meanwhile, since significant fill light is already provided via the ambient light, the intensity of the fill light provided by the lighting system is dimmed. Conversely, when the ambient light level is relatively low, the intensity of the key light is dimmed but still maintained above the ambient light level because a less intense key light is needed to maintain its stand-out function. On the other hand, since little fill light is provided via ambient light, the intensity of the fill light provided by the lighting system is boosted, but the key light is boosted to a level lower than the intensity of the key light to maintain its standout function.
[0058] The lighting system may have the feature that the number of light sources for each lighting device is equal to N, preferably configured to generate a 2D pattern having N patches. With N equal for each lighting device, each target portion of the target area can be individually controlled by at least two light beams, for example, to provide at least two different colors for each target portion and / or to provide key light and fill light. Thus, a single patch in the array of light patches includes both key light and fill light. It should be noted that the feature of a single patch including both key light and fill light can be obtained both with a single lighting device (in which case the lighting system includes at least two of these lighting devices) and with multiple lighting devices.
[0059] The lighting system may be characterized in that the number of first light sources, or key lights, is 2 to 20 times the number of second light sources, or fill lights. Thus, a simpler yet relatively sophisticated lighting system is provided. The lighting system may be characterized in that the key lights are configured to provide a light beam of a first width, typically within a first range of 5° to 30°, and the fill lights are configured to provide a beam of a second width, typically within a second range of 30° to 70°, the second width being wider than the first width, and one fill light cooperates with multiple key lights.
[0060] The lighting system may be characterized in that a first light source emits light toward a target area in a first direction and a second light source emits light toward the target area in a second direction, the second direction being at an angle γ with the first direction, γ being in the range of 10° to 160°, typically in the range of 40° to 120°. In this way, the so-called McCandless effect can be achieved, which is known to particularly enhance the attractiveness of displayed items illuminated in this way. It should be noted that the McCandless effect can be obtained both with a single lighting device (in which case the lighting system includes at least two of these lighting devices) and with multiple lighting devices.
[0061] The illumination system may further include a third light source substantially aligned with the light sources mounted on the first carrier and the further carrier. To this end, the illumination system may be characterized in that the third light source provides light having a third intensity higher than the first intensity of the key light and preferably higher than the combined intensity of the first and second lights to act as a pin light. Alternatively, the illumination system may be characterized in that the third light source is provided on a separate substrate that is out of alignment with the light sources mounted on the first carrier and the further carrier. To this end, the illumination system may be characterized in that the third light source is arranged out of alignment and configured to emit light in a direction essentially opposite to the light-emitting direction of the key light, and the third intensity is lower than the first intensity. Typically, in this case, the third light source is suitable for functioning as a backlight to further enhance a desired scene, but in combination with the backlight, a subset of the third light sources may be configured to provide uplight. The backlight and uplight may propagate in essentially the same direction, and thus a third light source may be included in a single lighting device that provides both said backlight and uplight.
[0062] It is further preferred that the lighting system has the feature that the third light source is configured to emit a third light of a third color different from the first color of the first light source. The lighting system may simultaneously provide both pin light and backlighting, and for this purpose, the lighting system includes a combination of lighting devices with third light sources, a subset of which is configured to provide pin light and another subset is configured to provide backlighting. Thus, the third light can be an uplight or a pin light. Pin or uplighting spots are also used in conjunction with backlighting. These are spots typically installed at the bottom front of a shop window. These are narrower beam spots typically used to highlight special details or create theatrical lighting effects from below. To further enhance the lighting effect, flashing key lights and / or pin lights may be included in the scene setting.
[0063] The lighting system may further have the feature that it includes a control unit for individual control / addressing of the lighting units of at least the first lighting device and the further lighting device. This feature allows for managing the local heat load on the lighting devices of the lighting system and helps to reduce the maximum temperature of the (local) heat load on the system. It is also convenient if all lighting units of each lighting device can be turned on / off simultaneously with a single switch, as this reduces the need for time-consuming operations when it is desired to (de)activate an entire lighting device. The same applies to turning on / off an entire lighting device row if the lighting system includes at least two parallel rows of lighting devices, for example 2, 3, 4 or 5 parallel rows. The lighting system may further include a first lighting device configured to emit a first beam type, a further lighting device configured to emit a further beam type different from the first beam type, the first beam type and the further beam type being tunable with respect to at least one of color, color temperature, CCT, and intensity, and a control unit configured to electronically change the first beam type of the first lighting device to the further beam type and the further beam type of the further lighting device to the first beam type simultaneously via a control signal. Thus, a lighting system with adjustable lighting devices may use the control unit to electronically switch the types of beams generated by the light sources, i.e., a key light coming from the right and a fill light coming from the left can be easily switched between them (especially if the same beam width is used for the key light and the fill light), resulting in a fill light coming from the right and a key light coming from the left, respectively. Such switching can be easily performed with respect to, for example, color, Tc, CCT, intensity, illuminance level, or luminous flux, etc.
[0064] The lighting system may be characterized in that the control unit includes a graphical display configured to display a patched pattern, typically formed by an array of patches on a target area. Optionally, the lighting system may be characterized in that the control unit includes a camera configured to display, picture and / or monitor the patched pattern in situ and / or in real time. This allows the effect of turning on / off each lighting unit to be directly seen, thus simplifying the setting of the (desired) light pattern. The camera may be or include a sensor as an integral (built-in) and / or non-integral (separate) device for measuring actual (ambient) lighting conditions in order to instantly adjust the light intensity of the beam projected onto the target area; for example, when ambient light levels are low (such as in the evening or at night), the light level provided to the shop window may be reduced to counteract glare and / or over-illumination, or during periods of bright sunlight, the illumination provided to the shop window may be boosted to still attract (potential) customers' attention to the items displayed in the shop window.
[0065] The lighting system may have the feature that the control unit is configured to be scene programmable to provide dynamic lighting scenes in a target area. In this way, improved presentation and / or enhanced attraction of (potential) customers to items displayed in the shop window may be achieved. To enable the lighting system to automatically adapt the scene settings to be displayed to the actual ambient conditions, the lighting system may have the feature that the type of programmable scene displayed / executed depends on the time of day and / or ambient light levels.
[0066] The lighting system may have the feature that the graphical display includes a touch screen by which the lighting units can be controlled, providing the lighting system with a user-friendly interface.
[0067] The lighting system may have the feature that it is configured as shop window lighting, however applications in street lighting or in interior lighting such as in the entrance halls of theatres, bars and / or hotels are also envisaged.
[0068] The present invention further provides a lighting method using a lighting system according to the present invention, comprising: selecting a scene for a target area; selectively turning on lighting units of each longitudinally extending lighting device to create a patched lighting pattern extending transversely to the longitudinal direction; evaluating the resulting lighting effect on the identified scene / target area; repeating the steps of selectively turning on lighting units of a lighting device and evaluating the resulting lighting effect until the scene is complete; The present invention relates to a method, comprising: The lighting method further includes: adjusting the obtained lighting effect; may include:
[0069] Typically, the setup for setting a scene, for example for a shop window, can be done locally, i.e. at the location of the shop window itself, but alternatively or additionally, said scene setting can be done remotely, for example by an expert from a central station from which various shop windows for various branches of a shop chain are controlled by said expert. For this reason, the method can be carried out from a remote location, taking a shot of a shop window in which a scene is to be set; transferring said shots via electronic means to a remote control station; selecting a scene for a target area; selectively turning on the lighting units to create a patched lighting pattern; evaluating the resulting lighting effect on the identified scene / target area; Optionally, adjusting the resulting lighting effect via a remote control at a remote control station; may include:
[0070] Typically, the shots (photographs) are in digitized form, and electronic means for transferring the shots are well known, such as via the Internet, email, wireless data communication systems, etc. Instead of performing the method step by step from a remote location, instructions for a new scene setting may be compiled and sent as a set of instructions to the target shop window. This method also makes it possible to monitor and / or maintain the status of a particular shop window, and upon detection of a failure of an active device of the lighting system, a signal can be created to repair the system, although alternatively or additionally, settings of other devices of the lighting system can be adjusted from a central, remote location to compensate for the failure of said active device. [Brief explanation of the drawings]
[0071] The present invention will be further clarified by means of diagrammatic drawings illustrating various embodiments which are not intended to be limiting but rather to illustrate the versatility of the invention. [Figure 1A] 1 is a perspective view of a shop window for explaining the principle of the present invention; [Figure 1B] 1B shows details of the three lighting units of FIG. 1A. [Figure 1C] 1 shows both a front view and a side view of a shop window to further illustrate the principles of the present invention. [Figure 1D] 1 shows both a front view and a side view of a shop window to further illustrate the principles of the present invention. [Figure 2A] 1 shows a front view of a shop window in which a target portion of a target area is illuminated by each of two lighting units. [Figure 2B] 1 shows a front view of a shop window in which a target portion of a target area is illuminated by each of two lighting units. [Figure 3A] 1 shows various arrangements of lighting devices and lighting units in a lighting system according to the invention; [Figure 3B] 1 shows various arrangements of lighting devices and lighting units in a lighting system according to the invention; [Figure 3C] 1 shows various arrangements of lighting devices and lighting units in a lighting system according to the invention; [Figure 3D] 1 shows various arrangements of lighting devices and lighting units in a lighting system according to the invention; [Figure 4] It shows that the key light has higher resolution than the fill light in the target area portion obtained by the illumination system shown in Figures 3A-D. [Figure 5A] Some examples of interleaving are given below. [Figure 5B] Some examples of interleaving are given below. [Figure 6] 1 shows a lighting device including parallel extending lighting devices with adjustable overlap. [Figure 7] 1 shows a comparison between conventional shop window lighting and shop window lighting using a lighting system according to the present invention. [Figure 8A] The mathematical relationship between the position of the lighting unit relative to the target area, the beam shape, and the shape of the patch projected onto the target area is described. [Figure 8B]The mathematical relationship between the position of the lighting unit relative to the target area, the beam shape, and the shape of the patch projected onto the target area is described. [Figure 9] 1 shows a control unit for individual control / addressing of lighting units of at least a first lighting device and a further lighting device; [Figure 10] 1 shows a step sequence for setting up a desired scene. DETAILED DESCRIPTION OF THE INVENTION
[0072] 1A shows a perspective view of a shop window 1000 in which an exhibit 1002 for illustrating the principles of the present invention is provided. To this end, FIG. 1A shows a first lighting device 1 comprising a linear row of eight lighting units 3 mounted on an elongated carrier 5 and extending only in a first direction X. Alternatively, the lighting devices, the carrier and / or the row of lighting devices may have a slightly curved shape, for example a curved shape spanning a curvature angle of at most 30°. Each lighting unit 3 is mounted in a respective, fixed, unique, predetermined orientation as indicated by its respective optical axis 7. The first lighting device 1 is configured to project a first array of light patches 9 directly onto a target area 11, i.e., a plane P, where the exhibit 1002 is located. The plane P extends in the first direction X and in a second direction Y transverse to the first direction (i.e., Δ≈90°, although slight deviations are possible) (when the directions XYZ are in a Cartesian coordinate system, Δ=90°). The first array of light patches 9 extends only in the second direction Y, forming a closed pattern 13. The lighting device 1 is offset from the plane P in a third direction Z. The sequence of the lighting units 3 differs from the sequence of the patches 9 in the patched light pattern 13 and is arbitrarily selected to reduce or optimize local thermal loads. In shading (shown in dotted lines), a further or next lighting device 1′ including a next array of lighting units 3′ and a corresponding next array of light patches 9′ are shown. As shown, the next (or further) lighting device 1′ is substantially aligned in the length direction X with the first lighting device 1 and together with the first lighting device 1 forms the lighting system 100. Also as shown, the next row of light patches 9′ is projected onto the target area 11 adjacent to the first row of light patches 9 and matches together to form a closed pattern 13′.
[0073] Alternatively, Figure 1A can also be considered as showing only a single lighting device, in which case the first lighting device and the further lighting device shown in Figure 1A are integrated into one lighting device, and the lighting units 3 of the first lighting device are referred to as a first plurality of lighting units 3 projecting a first plurality of light patches, and the lighting units 3' of the further lighting device 1' are referred to as a further plurality of lighting units 3' projecting a further plurality of light patches.
[0074] FIG. 1B shows details of three (first) lighting units 3 of the lighting device 1 of FIG. 1A. For each lighting unit 3 (respective light source, in the figure a respective LED), a fixed respective reflector is shown, having a respective (preferably transparent) light exit window 12 and a fixed respective optical axis 7. Also shown is a normal 14 (orthogonal line) to a main surface 15 of the elongated carrier 5 of the lighting device 1, the carrier 5 having a length Ld. As shown, each respective optical axis is at a respective angle relative to the normal. Furthermore, the first lighting unit 3a has a first optical axis 7a, and at least one further lighting unit 3b, 3c in the row of lighting units has a respective further optical axis 7b, 7c, with the maximum angle θ between the optical axes 7a-7c ranging from 10° to 80°, with θ being approximately 60° in the figure.
[0075] 1C-D show front views of a shop window 1000 to further illustrate the principles of the present invention. FIG. 1C shows a lighting system 100 including a first row of six (first and further) lighting devices 1 extending in a first direction X and located at a height of approximately 2.2 m above an exhibit 1002 in the shop window. For simplicity, each lighting device 1 includes only four lighting units 3. A first lighting device 1 a is configured to generate a first vertical row (also called a column) of four bounded, or optionally partially overlapping, light patches 9 a on a target area 11. As shown, the light patches 9 a extend only in a second direction Y transverse to the first direction X; i.e., for each lighting device, the number of associated light patches 9 a in the second direction Y generated by the respective lighting device is greater than the number of associated light patches 9 a extending in the first direction X. More specifically, the number of light patches 9a is shown here equal to the number of the first plurality of light patches generated by each associated lighting device, with only one light patch in the first direction X being selected. In the figure, only the first lighting unit of the first lighting device is activated (switched on) to generate the first light patch of key light in the target area. Here, the sequence of the lighting units is the same as the sequence of the light patches, i.e., the lighting units are arranged from left to right in the lighting device, and the corresponding light patches are arranged from top to bottom in the same order. Similar to the first lighting device, the second lighting device 1b is configured to generate a second row of four patches 9b in the target area, and in the figure, only the second lighting unit of the second lighting device is activated (switched on) to generate the second light patch of key light in the target area. Similarly, the third and fourth lighting devices (counting from left to right) are activated, while the fifth and sixth lighting devices are not activated. Thus, the lighting system illuminates the target area with the desired (closed) lighting pattern of the key light. Similarly, fill light is provided, shown as being provided by lighting device 1g.The spot size of the fill light is about three times larger than the spot size of the key light. In the right part of the figure, a side view of a shop window is given, showing that the lighting devices for providing key light, designated by the letter A, are all aligned in a line, while the lighting devices for providing fill light, designated by the letter B, are parallel to but out of line with the lighting devices for providing key light. As shown in the right part of the figure, the relative positions of the key light and fill light are designated by the letters A and B, respectively. By activating only specific lighting units, a desired light pattern can be created to highlight desired details of the exhibit.
[0076] FIG. 1D shows a lighting system 100 similar to that shown in FIG. 1C, but here the lighting system is located on the floor of a shop window 1000 to provide uplighting as backlighting. In the lighting system of FIG. 1D, all six lighting devices 1 for providing uplighting are operational, i.e., all four lighting units 3 of each lighting device are turned on, and the target area is fully illuminated by various vertical rows (columns) of light patches 9 (which are not shown with overlap for illustrative purposes only, but in reality there may be overlap between adjacent light patches). Again, the sequence in the lighting units is the same as the sequence in the light patches. In the right part of the figure, a side view of the shop window 1000 is provided, showing the position of the backlight, designated by the letter C, which here functions as an uplight, relative to the positions of the key light (designated by the letter A) and the fill light (designated by the letter B) in the shop window.
[0077] 2A-B show front views of a shop window 1000 in which several target portions of a target area 11 are illuminated by respective first and further (second) lighting devices 1a, 1b. The lighting system 1 shown in FIG. 2A includes two parallel lighting device rows 4a, 4b extending in a first (X) direction, of which only some lighting units 3 (LED reflector units in the figure) are turned on. The first lighting device row 4a provides key light to the target area 11, and the second lighting device row 4b provides fill light to the target area with a different CCT, i.e., a higher color temperature (Tc) or a higher correlated color temperature (CCT), than the key light. The LEDs of the first lighting device emit light toward the target area in a first direction, and the second LEDs of the second lighting device emit light in a second direction, which is at an angle γ with the first direction, where γ ranges from 10° to 400°. In this way, the so-called McCandless effect can be achieved, enhancing the attractiveness of the illuminated exhibits.
[0078] The lighting system 100 shown in FIG. 2B comprises two fixed, parallel rows of lighting devices extending in a first (X) direction, namely, a first row of lighting devices 4a and a further row of lighting devices 4b, some of which lighting units 3 are turned on, i.e., in this case, only lighting devices for emitting both key light and fill light of mutually different Tc or CCT in the target area where the exhibit is located are turned on. Note that the spot sizes of the key light patches and fill light patches are (approximately) equal. Parts of the target area to be illuminated by the lighting units where the exhibit is not located are in the off state. In this way, it is achieved that the exhibit 1002 stands out in the shop window 1000 and attracts more attention.
[0079] For example, a known lighting system including five conventional spots from Philips Magneos, each typically having a luminous flux of at least 3000 lm and a size of 0.26 x 0.16 m, can be replaced by the lighting system 100 shown in Figures 2A-B. In this case, the lighting system of the present invention typically includes approximately 150 high-power LEDs (each emitting approximately 200-400 lm) as lighting units 3, or alternatively, 300-400 mid-power LEDs (each emitting approximately 60-100 lm) as lighting units. Although the schematic diagrams of Figures 2A-B show only a limited number of these lighting devices 1, i.e., six lighting devices 1 in a row, in reality this number is approximately eight, and each lighting device in the figures only includes four LEDs plus a collimator as lighting unit 3, but in reality each lighting device includes approximately 10 lighting units. With this number of lighting units, a matrix of light spots approximately 8-16 pixels high and approximately 10-20 pixels wide can be created. The light generated by the LEDs is concentrated by small optical elements per LED, typically 1-2 cm in diameter per optical element. Thus, a light bar may contain a single row of lighting devices, typically about 1-2 cm wide and about 1.5-2.0 m long. Two or three parallel rows of lighting devices 4a, 4b typically have a cross-section with a diameter of about 6 cm together. Note that creating an addressable matrix of pixels does not require significant over-installation of LEDs. The amount of light generated will be comparable to conventional systems (installed for maximum light output during clear daylight hours), and the light pattern is created by turning off the pixels when less light is needed (evening / nighttime).
[0080] 3A-D show various configurations of first and further lighting devices 1, each including three lighting units 3, in a lighting system 100 according to the present invention. All configurations shown in FIGS. 3A-D illustratively include 18 lighting units 3 in six lighting devices 1a providing patches of key light and six lighting units 3b in two lighting devices 1b providing patches of fill light, divided among a total of eight lighting devices 1a, 1b. In the configuration of FIG. 3A, the lighting system includes two parallel rows of lighting devices 4a, 4b. The first row 4a includes six lighting devices 1a aligned in the length (X) direction, and the second row 4b includes two lighting devices 1b aligned in the length direction and parallel to the first row. The 18 key lights are divided among the six lighting devices in the first row 4a, each including three lighting units 3, and the six fill lights are divided among the two further lighting devices in the second row 4b, each including three lighting units. 3B-D show the same lighting devices and lighting units in alternative arrangements, where in FIG. 3B all lighting devices 3 are arranged in a single row 4, aligned lengthwise (X). FIG. 3C shows the same arrangement as FIG. 3A, but with the additional feature that the first row 4a and second row 4b are shiftable relative to each other along the lengthwise direction (X direction), allowing for shifting patches of fill light over patches of key light in a target area. FIG. 3D shows an arrangement of two parallel rows of lighting devices of equal length, where the first row 4a includes 12 key lighting units 3a and the second row 4b includes 12 lighting units in an interdigitated configuration of key lighting units 3b' and fill lighting units 3b".
[0081] FIG. 4 shows an example of a target area 11 patched with key light patches 51 and fill light patches 53. In this embodiment, the key light patches are shown smaller than the fill light patches, resulting in higher resolution for the key light than for the fill light on the target area portion, as obtained by the lighting system shown in FIGS. 3A-D. To fully cover the target area with both key and fill light, the size of the light patches generated by the key lighting unit is relatively small, while the size of the fill light patches generated by the fill lighting unit is relatively large, with the ratio of the patch size of the fill light patches to the size of the key light patches being approximately 3. A slight overlap between adjacent light patches is allowed and is shown. Furthermore, the light patches are each numbered, and the numbering corresponds to the numbering of the lighting units shown in FIGS. 3A-D. In most cases, i.e., except for the arrangement shown in FIG. 3D, the sequence in the lighting units is the same as the sequence in the light patches.
[0082] 5A-B show two examples of interleaving. On the right side of FIG. 5A, two examples of lighting systems 100 including two lighting devices 1 are shown, each with an arrangement of seven lighting units 3 per lighting device. Here, as shown on the left side of FIG. 5A, the row positions of the lighting units do not necessarily correspond to the column positions of the spot pixels / patches 51 on the target area 11. Numbers within a lighting unit are associated with the same numbers in the target area, and thus the row positions of the lighting units are coupled to the column positions of the patches in the target area. The coupling between row and column positions can be pre-arranged according to a desired algorithm, as is the case in FIGS. 5A-B, but can alternatively be selected arbitrarily. By selecting a particular arrangement, the positions of the lighting units in the lighting device can be optimized, for example, to distribute the thermal load, depending on, for example, the desired lighting pattern. Notably, a layout such as the embodiment shown in FIG. 5B can also achieve a more even distribution of the thermal load. FIG. 5B shows four light patches 51 projected next to each other in the target area 11. This may result in localized heat loads in a lighting system 100 including two lighting devices 1, where the corresponding lighting units 3 generating the light patches are located next to each other. Yet, FIG. 5B shows that the corresponding lighting units are more or less evenly distributed across the two lighting devices 1, thereby distributing the heat load in the lighting system. If the fill light patches are very wide and largely overlap when projected into the target area, the exact location of the fill lights in the lighting system is less relevant, and this can be used to further counteract the high, localized heat load of the lighting system. In this case, fill light sources close to the hot spot (where the adjacent key lights are all on) can be dimmed, and other fill lights can be increased to compensate.
[0083] 6 shows a lighting system 100 including two rows 4a, 4b of lighting devices 1 extending parallel to the X (length) direction, with an adjustable overlap between the two rows. The first row 4a includes lighting devices 1a with lighting units 3a providing key light with a certain Tc or CCT, for example, 3000K, and the second row 4b includes second lighting devices 1b with second lighting units 3b providing fill light with a higher Tc or CCT, for example, 5000K. The LEDs of the first lighting units emit light to a target area in a first direction 55, and the LEDs of the second lighting units emit light in a second direction 57, where the second direction is at an angle γ with the first direction, γ being approximately 70°, thus achieving the so-called McCandless effect. By shifting the second row relative to the first row in the X direction, the so-called McCandless effect can be tuned and / or optimized at a desired location in the target area by emitting lights of different CCTs with different beam angles aimed at the same location in the target area from different positions. Typically, this feature is used to particularly enhance the appeal of a particular part of an exhibit.
[0084] 7 shows a comparison between a conventional lighting system 101 for a shop window 1000 and a lighting system 100 according to the invention for illuminating the shop window 1000, in both a front view and a side view of the shop window. As shown, the conventional lighting system comprises four conventional lighting units 102 which are mounted at a relatively high position, which makes them relatively bulky and obtrusive. In contrast, the lighting system of the invention has a relatively large number of lighting units, for example 100 or more lighting units, which are mounted at a relatively low position and relatively unobtrusively, and which are included in several lighting devices 1. This makes the lighting system of the invention advantageous over known lighting systems, for example in the following respects:
[0085] - High resolution of light patches to illuminate target areas, which offers more possibilities to create desired and more refined lighting patterns.
[0086] - The use of multiple lighting units to illuminate the same patch of a target area, which makes it possible to create, for example, a McCandless effect by using lighting units with different beam angles and different CCTs aimed at the same spot on the target area from different positions.
[0087] - Great possibilities for creating dynamic lighting scenes.
[0088] - the desired lighting scene / pattern is easier to install, e.g. can be adjusted from an easy-to-reach or remote position (no need to use a ladder), reducing the risk of injury to staff such as shop window designers and reducing the risk of damage and / or distortion of exhibits;
[0089] 8A-B illustrate the mathematical relationship between the position of the lighting unit 3 relative to the target area 11, the beam shape 59, and the shape of the patch 51 projected onto the target area. In FIG. 8A, the effect of distance and projection angle on the spot shape is shown. To ensure that each light beam emitted by each lighting unit along its respective optical axis 7 results in the same intensity I on the target area, I obeys the following relationship: I → (2 * L * tan α) 2 where α is the angle between each optical axis 7 and the inclined target area 11 (plane Q), α is in the range of 5° to 85°, and L is the distance between each lighting unit and the target area.
[0090] However, essentially, the spot will be more or less elliptical, with the minor axis depending only on the distance between the light source and the illuminated surface, and the major axis also depending on the projection angle. To create a more or less circular patch with a constant diameter, the beam width must scale with the projection distance, and the beam angle must be asymmetric (approximately elliptical) to compensate for the projection angle. The relationship between beam angles β1, β2, projection distance L, and tilt angle α is shown in Figure 8B and follows at least substantially the following relationship:
[0091] To generate a circular patch on the inclined surface of the target area 11, each lighting unit 3 generates a respective light beam according to the following relationship: tanβ1=D*cosα / (2*L+D*sinα) tanβ2=D*cosα / (2*LD*sinα) where β1 and β2 relate to the beam width angles of the half beam portions on either side of the optical axis 7 of the lighting unit 3 for the part of the inclined surface of the target area far from the lighting unit and the part of the inclined surface close to the lighting unit, respectively; α is the angle between the respective optical axis and the (plane of) the inclined target area, α is in the range of 5° to 85°; and L is the distance between the respective lighting unit and the target area.
[0092] FIG. 9 shows a control unit 201 for individual control / addressing of the lighting units 3 of at least the first lighting device and the further lighting device. The control unit includes a graphical display 203, including a touchscreen 205 as a convenient user interface, and is configured to display, image, and / or monitor the patched pattern formed by the rows of patches on the target area on-site. To display the patched pattern on-site, the control unit includes a (live) camera 207. Furthermore, the control unit is configured to be scene-programmable to provide dynamic lighting scenes for the target area. Typically, the setup for setting a scene, e.g., for a shop window, can be performed locally, i.e., at the shop window itself; alternatively or additionally, the scene setting can be performed remotely, e.g., by an expert from a central station where various shop windows for various branches of a shop chain are controlled by the expert. For this purpose, the control unit includes a transmitting / receiving unit 209 for wireless electronic communication. When performed locally and standing outside the shop window, a person can take a photo of the current shop window scene and, with the help of a touch screen or alternatively or additionally a drawing device, can set the shop window 1000 scene to the desired setting by specifying which parts of the scene should be highlighted and which parts can be left in darkness. The desired effect is achieved by activating only the key and fill light spots (both indicated by the letter A) that illuminate a specific area in a vertical plane. Thus, a person first indicates the preferred area for the key and fill lighting effect. Only the spots aimed at this specific area are turned on. This results in certain spots providing key light, while other spots provide fill light to reduce over-contrast full shadows. Spots aimed at unused areas are not activated.
[0093] Optionally, one can then indicate whether and where a backlight effect is required. In the same principle, a matrix of spots placed in the backlight matrix (denoted by the letter B) can cover the complete vertical display surface, but now from the back. See the cross-sectional diagram for the position of the backlight matrix. In practice, only some spots are activated, for example to light hair from behind, while others are off.
[0094] In line with backlighting, the same principle is also applied to realize up or pinlights. These are spots (denoted by the letter C) that are usually installed at the bottom front of a shop window. They are usually narrower beam spots used to highlight special details or to create theatrical lighting effects from below. Using the same principle, a matrix of LED spots installed in an uplight matrix can cover the complete vertical display surface, but now from below and in front. See the cross-sectional diagram for the position of the uplight matrix.
[0095] Three separate matrices allow for the realization of complete lighting scenes, including key lighting, fill lighting, back lighting, up lighting, and pin lighting. Adding a light sensor or candelameter 211 to the control unit or lighting system of the shop window itself allows for measuring the lighting level or brightness within the shop window on the display in areas without spotlights. This allows for lowering the intensity of the spotlight when the daylight level drops, while maintaining the same contrast ratio. Thus, for example, during the day, it is possible to measure the ambient light level within the shop window due to daylight. For example, if the accent factor is 5, the lighting level on the display should be five times higher than the daylight lighting level. If the daylight level within the shop window falls below a certain value, a lower spot intensity can be used to maintain the contrast ratio.
[0096] Finally, at night (e.g., at levels below 20 lux), accent values of 1:40 or higher can be easily achieved with dimmed spots because daylight levels are close to zero. This dimming option at night has a positive impact on both energy consumption and the desired light balance of the shop window. Second, the system allows for dynamic scenes to be created by switching between or dimming various spot groups. The accent factor can be changed, and the incidence angle can be altered using different spot groups. Slow fade-over scenes can also be created in this way. The orientation of the key, fill, and back / pin lights relative to each other can be selected to optimize the desired scene setup. For a more realistic / natural and appealing effect, it is preferable to use spots with two different color temperatures and different beam angles aimed from different positions. Like daylight outdoor situations, skylight diffused by clouds is usually directionless and cooler than directional sunlight. To mimic this effect, a narrow beam spot with a low color temperature from one side, i.e., a key light, is typically used, which mimics directional warm sunlight. To fill in the (too harsh) shadows, a wide beam spot with a higher color temperature from the other side, i.e., fill light, is used to simulate cooler stray light or blue sky light. Typically, it is preferable to have the key light and fill light on opposite sides at a 45° horizontal angle and a 30° vertical angle.
[0097] As mentioned above, the method may be performed from a remote location. Typically, the shots (photographs) are in digitized form, and electronic means for transferring the shots are well known, such as via the Internet, email, wireless data communication systems, etc. Instead of performing the method step by step from a remote location, instructions for a new scene setting may be compiled and sent as a set of instructions to the target shop window. This method also makes it possible to monitor and / or maintain the status of a particular shop window; upon detection of a failure of an active device of the lighting system, a signal to repair the system may be generated; alternatively or additionally, settings of other devices of the lighting system may be adjusted from a central, remote location to compensate for the failure of said active device.
[0098] 10 shows the sequence of steps to follow to set up a desired scene, for example in a shop window. Step 301 of taking a shot of a shop window where a scene is to be set; a step 303 of transferring said shot via electronic means to a remote control station; selecting a scene for a target area; Step 305 of selectively turning on lighting units to create a patched lighting pattern; a step 307 of evaluating the resulting lighting effect on the identified scene / target area; Optionally, Step 309 is performed to adjust the resulting lighting effect by an iterative cycle of steps 305 and 307 until a satisfactory result for the scene setting is achieved.
[0099] Optionally, this sequence of steps can be performed via remote control at a remote control station.
Claims
1. an elongated carrier having a length; a first plurality of lighting units mounted in a linear row on the carrier and extending only in a first direction along the length of the elongated carrier, the first plurality of lighting units including at least five lighting units; 1. A lighting device comprising: each lighting unit of the first plurality of lighting units is mounted in a respective fixed, predetermined orientation, and the first plurality of lighting units are configured to project a row of a first plurality of light patches directly onto a target area extending in the first direction and a second direction transverse to the first direction; An illumination device, wherein the first plurality of light patches form a light pattern, and the number of light patches in the first plurality of light patches in a second direction transverse to the first direction is greater than the number of light patches in the first direction.
2. 2. The lighting device of claim 1, wherein the lighting device includes at least one further plurality of lighting units extending only in the first direction, the at least one further plurality of lighting units configured to directly project further light patches to form an integrated light pattern that combines with the first plurality of light patches projected by the first plurality of lighting units.
3. 3. The lighting device of claim 2, wherein the further light patches are projected parallel to and adjacent to the first plurality of light patches in the first direction.
4. 4. A lighting device according to claim 2 or 3, wherein the at least one further plurality of lighting units is an extension of the first plurality of lighting units.
5. 4. The lighting device according to claim 2 or 3, wherein a second plurality of lighting units or a second and a third plurality of lighting units of the at least one further plurality of lighting units are arranged parallel to and next to the first plurality of lighting units.
6. 6. A lighting device according to any one of the preceding claims, wherein the respective fixed predetermined orientations are specific to each lighting unit.
7. 7. A lighting device according to any one of the preceding claims, wherein the respective solid beam angles of the respective lighting units are such that all light patches have substantially the same shape.
8. 8. A lighting device according to claim 2, wherein the first lighting unit and the further lighting unit have a sequential arrangement that is different from a sequential arrangement of the first light patches and the further light patches projected by the first lighting unit and the further lighting unit.
9. 9. A lighting device according to any one of the preceding claims, wherein the lighting unit (10) is configured to generate a beam with an adjustable solid beam angle.
10. 10. A lighting device according to any one of claims 1 to 9, wherein essentially each of the lighting units comprises a respective at least one associated light source, the at least one associated light source comprising LEDs of different colours, colour temperatures and / or CCTs.
11. 11. A lighting system comprising a first lighting device according to any one of claims 1 to 10 and at least one further lighting device arranged substantially longitudinally.
12. 12. The lighting system of claim 11, wherein the at least one further lighting device is configured to directly project further light patches to form a unified light pattern that combines with a first light patch projected by the first lighting device.
13. 13. The lighting system according to claim 11 or 12, wherein a second lighting device or second and third lighting devices of the at least one further lighting device are arranged next to the first lighting device.
14. 14. The lighting system of claim 13, wherein the light sources of the first lighting device and the second lighting device are positioned in an alternating zigzag configuration along the length direction and / or are shiftable relative to one another in the length direction.
15. 15. The lighting system of claim 11, wherein the first lighting device comprises a first light source of a first color, color temperature or CCT and the second lighting device comprises a second light source of a second color, color temperature or CCT different from the first color, color temperature or CCT of the first light source.
Citation Information
Patent Citations
lighting equipment
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