Method for regulating or controlling a light fixture

Abstract

Method for regulating or controlling a luminaire (2) with direct and indirect light emission with respect to a work area (A) in a room (R) with ambient light (F) F , F L ), such as daylight and / or light from other light sources influencing the work area, by means of a light control system (1) with the luminaire (2) and a light control unit (1.1) having a light sensor (3), with the process steps that by means of the light control system (1) with increasing exposure to extraneous light (F F , F L ) into the work area (A) first a dimming of the indirect light component (L I ) of the luminaire (2) and subsequently a dimming of the direct light component of the luminaire (2) and / or with decreasing ambient light (F F , F L ) into the work area, first a dimming up of the direct light component (L D) of the luminaire (2) and subsequently a dimming up of the indirect light component (L I ) of the light (2).

Description

[0001] The invention relates to a method for regulating or controlling a luminaire with direct and indirect light emission with respect to a work area in a room with ambient light, such as daylight and / or light from other light sources influencing the work area, by means of a light control system comprising the luminaire and a light control unit having a light sensor.

[0002] Such a method or lighting control system is generally known. When illuminating a work area, certain lighting criteria must be observed, which, among other things, relate to uniform and consistent illumination of the work area. This includes the indirect light emission from the luminaire. The luminaire, for example as a ceiling light, can emit indirect light towards the ceiling. Increasing visual comfort and counteracting eye strain, the indirect light emission illuminates the area around the luminaire and the work area lit by the direct light. A portion of this indirect light emission, for example via reflection off the ceiling, indirectly illuminates the work area.

[0003] In a room with ambient light, i.e., light not originating from the luminaire designated for the work area but shining into the work area, the illuminance of the luminaire intended for workplace lighting must be adjusted to the additional ambient light intensity present in the work area. This is particularly necessary when the ambient light fluctuates, requiring compensation in the work area lighting. This ensures consistently uniform illumination of the work surface and can also save electrical energy. A common lighting control system involves dimming the luminaire upwards as ambient light decreases and downwards as ambient light increases. Ambient light can consist, for example, of daylight entering the work area through windows and / or light from neighboring luminaires.

[0004] WO 2012 / 123352 A1 stipulates that the luminaire for illuminating a workplace is designed with communication means for exchanging information with a multitude of luminaires in order to select an operating state based on selection information wirelessly received by a luminaire. In this way, remote luminaires can communicate with the luminaire and react to its operating state by contributing ambient light to illuminate the workplace.

[0005] DE 196 08 224 A1 discloses a lighting arrangement with a light sensor for monitoring the illuminance at the workplace, in particular on the work surface, in order to either switch off the light sources in stages when predefined limits are exceeded or to continuously reduce their luminous intensity to zero by means of a dimmer circuit. The light sensor is arranged close to the work surface on the housing of the light source in such a way that it is not directly struck by the light from the light source.

[0006] The object of the invention is to provide a method of the type mentioned above or a lighting control system of the type mentioned above, by means of which further electrical energy can be saved without thereby impairing the lighting of the workplace.

[0007] The stated problem is solved according to the invention by the features of claim 1. Advantageous embodiments are described in the dependent claims. The stated problem is already solved by the fact that the method comprises the steps whereby, by means of the light control system, as the ambient light irradiation in the work area increases, first an indirect light component of the luminaire is dimmed down and then a direct light component of the luminaire is dimmed down, and / or as the ambient light irradiation in the work area decreases, first the direct light component of the luminaire is dimmed up and then the indirect light component of the luminaire is dimmed up.

[0008] Instead of dimming the entire light output of the luminaire, as is generally common practice, it is proposed to regulate or control the different light components of the luminaire—the direct and indirect light components—separately. When the ambient light level increases or even rises suddenly, the indirect light component is dimmed first, before the direct light component. The indirect light component is reduced first. Simultaneously, the direct light component can be maintained at a specific level. At the same time, the area around the luminaire can be illuminated with the increasing ambient light. This energy-saving approach ensures that the less efficient component of the light output for illuminating the work area—the indirect light component—is dimmed first.

[0009] Conversely, if the ambient light level decreases or drops suddenly, the direct light component can be dimmed up first before the indirect light component. This allows the direct light component to be maintained at a prescribed illumination level while the indirect light component is subsequently dimmed up. In both cases, visual comfort in the work area is maintained. Since the indirect light component of the luminaire is only minimally efficient for illuminating the work area, but the work area must be consistently illuminated, dimming the indirect light component first when ambient light increases, or dimming it last when ambient light decreases, results in significant energy savings.

[0010] In particular, it can be provided that, as the ambient light input into the work area increases, the direct light component of the luminaire is only dimmed by the lighting control system after the indirect light component of the light emitted by the luminaire has been dimmed to an illuminance of zero or near zero. Similarly, as the ambient light input into the work area decreases, the indirect light component of the luminaire can only be dimmed up by the lighting control system after the direct light component of the light emitted by the luminaire has been dimmed up to a specific upper illuminance limit. Thus, once a specific upper illuminance of the evaluation area is reached by the luminaire and as daylight continues to decrease, the indirect light component of the luminaire can be dimmed up. Preferably, the upper illuminance limit is adjustable.Each of these measures can achieve optimal energy savings.

[0011] To measure the illuminance of the luminaire in the work area, the lighting control system for carrying out the procedure for controlling the luminaire with direct and indirect light emission can have an evaluation surface arranged in a radiation path with indirect and direct light emission from the luminaire for evaluating the illumination of the work area.

[0012] The light sensor can be designed to detect the illuminance of the evaluation area and can also be positioned and directed towards it. The signal from the light sensor can serve as a control variable for the lighting control system. Thus, the light sensor can generate a signal for controlling or regulating the luminaire, derived from a measurement of the illuminance of the evaluation area, whereby the direct and indirect light emissions of the luminaire can be controlled or regulated separately.

[0013] For structural simplification, the light control system and / or the light sensor can be integrated into the luminaire. In this case, the evaluation area can also be positioned away from the luminaire. Preferably, the evaluation area and the working surface are arranged in a common beam path of the luminaire. Preferably, the evaluation area is positioned centrally to the working surface. For a structurally simpler design, the evaluation area can be integrated into the working surface. To minimize the risk of accidentally covering the evaluation area, for example, the evaluation area can be provided on a plateau positioned closer to the luminaire with respect to a plane of the working surface. The plateau can be part of a component forming the working surface.

[0014] For measurement-related simplification, the evaluation surface can be arranged at an angle, preferably perpendicular or approximately perpendicular to the main radiation direction.

[0015] To simplify measurement, the light sensor can also have a main measuring direction for measuring illuminance. Furthermore, the evaluation surface can be arranged perpendicular to the main measuring direction. In particular, the light sensor can be arranged on an emission side of the luminaire designed for direct light emission. In this case, the light sensor can have lateral shielding elements to protect against lateral stray light. Preferably, the light sensor is arranged centrally on the main emission side.

[0016] The evaluation surface can be positioned centrally to the main radiation direction with respect to a projection of the same against the main radiation direction on the radiation side.

[0017] The work area can include a work surface. The evaluation surface and the work surface can be arranged parallel to each other, spaced apart, or in the same plane. The work surface can constitute the evaluation surface. The evaluation surface can be part of the work surface.

[0018] The work area can have multiple evaluation surfaces. A light sensor for the lighting control system can be provided for each evaluation surface. For example, the work area can comprise several evaluation surfaces, preferably spaced apart from one another. This allows the illuminance of different areas of the work surface, or of the work area in general, to be measured. Advantageously, the illuminance of the different areas can be controlled separately. The illuminance control can be differentiated for various areas of the work area. The evaluation surfaces can be arranged in a grid pattern across the work surface, enabling grid-based measurement of the illuminance.

[0019] Indirect light emission can be achieved, for example, by extracting light from the main emission direction and / or from lateral scattered light of the luminaire, for instance via light guides or mirrors, and directing or deflecting it towards the indirect light emission. Alternatively, at least one additional light source, coupled to the light control system, can be provided for indirect light emission. This light source can include optics, preferably wide-beam or slightly diffusing optics for scattering the light, or focusing optics for illuminating an immediate wall or ceiling section behind the luminaire opposite the main emission direction.

[0020] In an advantageous embodiment of the light control system, the luminaire can have first light sources for direct light emission and second light sources for indirect light emission. The light sources can be light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), and / or electroluminescent films (EL films). Particularly when using point-like light sources, such as LEDs or OLEDs, the luminaire can have a light source grid with the point-like light sources as grid points.

[0021] Each point light source or group of point light sources in different areas or overarching patterns, such as a grid or honeycomb structure, can be individually controlled and dimmed. The control of the point light sources can be differentiated, for example, based on different sections of the work area. For instance, in a work area near a window, areas of the grid with point light sources closest to the window can be dimmed more intensely and / or more quickly than areas of the grid with point light sources farther from the window.

[0022] For example, a specific evaluation area can be designated for each section. At least the majority of the evaluation areas can each be assigned a light sensor. Each light sensor can be assigned a specific number of primary and / or secondary light sources. The number of primary and / or secondary light sources assigned to a light sensor can vary from sensor to sensor.

[0023] The present invention will be explained in more detail below with reference to several embodiments of the light control system illustrated in a drawing. The drawing shows: Fig. 1 A schematic side view of a room with a work area, a lighting control system for illuminating the work area, and with ambient light shining into the work area. Fig. 2 a diagram with illuminance E v depending on time t, Fig. 3 a schematic side view of an embodiment of a luminaire of the lighting control system, Fig. 4 a schematic layout on a work surface of the work area with integrated evaluation areas and Fig. 5 a schematic side view of a room similar to that in Fig. 1, however, with extraneous light shining into the work area from two sides.

[0024] In the Fig. Figures 1 and 3 to 5 show a room R with a work area A comprising a work surface AF in schematic diagrams. The work area A is illuminated by a lighting control system 1 with a luminaire 2 and a lighting control unit 1.1 incorporating a light sensor 3. The light sensor 3 is integrated into the luminaire 2. The luminaire 2 emits light with a direct light component L. D and indirect light component L I Furthermore, the work area A is illuminated by extraneous light F. F, F L , that is, illuminated by light from a light source outside the work area A. The indirect light component L I Its primary purpose is to brighten rooms not covered by direct light (L). D illuminated area around the light 2. The indirect light component L I The light from luminaire 2 is reflected off the ceiling D of room R and illuminated as the reflected light component L. R also the work area A or its work surface AF. Electronic and electrical components of the light control are invisibly integrated into the luminaire 2.

[0025] Using the light control system 1, the direct light component L D and indirect light component L I Independently controllable or adjustable. For evaluating illuminance E vIn the working area A, or in this case the work surface AF, which is illuminated by the luminaire, at least one evaluation surface 4 is provided as part of the lighting control system 1, which here is part of the work surface AF. In the embodiments of the lighting control system 1 shown here, the evaluation surface 4 and the work surface AF are arranged perpendicular to a main emission direction a of the luminaire 2. Thus, work surface AF and evaluation surface 4 are in the Fig. 1 and Fig. 5 are arranged perpendicular to the plane of the drawing and are only indicated by a line. The evaluation area 4 is, as directly shown, the Fig. 1 and Fig. 5 is evident in the radiation path of the direct light component L D and the portion of light reflected from the ceiling D L R of the indirect light component L I arranged. The evaluation area 4 is also part of the work area AF.

[0026] The light sensor 3 is used to detect the illuminance Ev , where light L is emitted from the evaluation surface 4 to the light sensor 3 S is reflected. The signal from light sensor 3 is a control variable for the light control system 1. As shown with dotted lines in Fig. As indicated in 1, optionally more than one evaluation area 4 with each assigned light sensor 3 can be provided, which allows, among other things, a better detection and additional adjustment of the light distribution with respect to the work area AF.

[0027] The plan is that, with increasing exposure to extraneous light F F , F L In working area A, using the light control system 1, first a dimming of the indirect light component L I of the light 2 and subsequently a dimming of the direct light component L D The luminaire 2 is activated. Accordingly, F occurs when the ambient light intensity decreases. F , F L In working area A, first an increase in the direct light component L Dof light 2 and subsequently a dimming up of the indirect light component L I the light 2.

[0028] This connection is in Fig. 2 is shown in a diagram showing the course of the illuminance E detected by the light sensor 3. v The phenomenon is qualitatively represented as a function of time t. Here, a very simple case is assumed, in which the ambient light F F , F L the illuminance E v The rating area 4 increases linearly, so that in return the indirect light component L is increased first. I of the luminaire 2 and thus its illuminance E v Regarding the evaluation area 4, it is reduced here to zero (curve profile III, at t=t1).

[0029] Following this (at t>t1), the direct light component L D The luminaire 2 is lowered (curve II) until a certain illuminance value E is reached at t=t2. vis achieved, which corresponds to a prescribed illuminance E v This corresponds to the work area AF. This is defined as the target value E. v ziel illuminance E v This is shown in curve I, which combines curves II and III. (For clarity, curve I is shifted upwards compared to the other two curves II and III, without this representing a quantitative difference.) With decreasing ambient light F F , F L In working area A, the dimming process shown in the diagram occurs in the opposite direction, i.e., in the direction of a "negative" time from right to left, by first dimming the direct light component L. D of the light 2 and then the indirect light component L I The light 2 is raised.

[0030] It is understood that the light control system 1 is also designed to accommodate any other course of ambient light F. F , F L how to react in principle to non-linear, periodically changing and / or suddenly changing conditions, as well as combinations thereof, in the same way: With increasing ambient light F F , F L First, the indirect light component L I and then the direct light component L D dimmed down, while with decreasing ambient light F F , F L first the direct light component L D and then the indirect light component L I is dimmed up.

[0031] To control the direct light component L D and the indirect light component L I indicates how in Fig. Figure 3 shows a schematic side view of an embodiment of the luminaire 2, which includes first light sources 5.1 and second light sources 5.2. The first light sources 5.1 are located on the underside 6 of the luminaire 2, which points in the main emission direction a, and the second light sources 5.2 are located on the top side 7 of the luminaire 2, which faces the ceiling D. The first light sources 5.1 and the second light sources 5.2 can be controlled or regulated separately from each other.

[0032] Here, the first light sources 5.1 and the second light sources 5.2 are each designed as LEDs 8, arranged in a grid pattern on the underside 5 and the top side 7, respectively, with the LEDs 8 on the underside 5 being concealed by a side panel 9. Additionally, a total of eight light sensors 3 are arranged on the underside, with four front light sensors 3 aligned with and concealing the four rear light sensors.

[0033] In Fig. Figure 4 shows a top view of a work surface AF of the work area A. Eight evaluation surfaces 4 are indicated in a grid pattern by dotted circles, each of which corresponds to a light sensor 3 ( Fig. 3) are assigned. This grid-like arrangement also allows for differentiated control of the LEDs 8, whereby the LEDs adjacent to a light sensor are grouped together for control purposes. Thus, the individual groups of LEDs can each be controlled via the signal of the assigned light sensor 3. At least the majority of the evaluation areas 4 can each be assigned a light sensor 3. Areas near windows in the work area A, which receive ambient light F through the window F, can be included. FThe lighting can be more strongly influenced and thus regulated differently than areas of work area A farther from the window, for example, with the aim of achieving a permanently uniform illumination of work area A or work surface AF. Furthermore, this allows certain areas of work area A or work surface AF to be illuminated more brightly than others.

[0034] In Fig. Figure 5 is another schematic side view of a room similar to the one in Fig. 1 shown, however, here extraneous light F from two sides F , F L radiates into work area A. Similar to in Fig. 1. Ambient light F shines here from the right. F through window F into the work area, ambient light F F one. Additionally, ambient light F emanates from an adjacent work area Ab with work surface AFb by means of its associated light 2b. Linto the work area A, whereby this extraneous light F L The illumination of the evaluation areas 4 is also affected. Since the signal from the light sensor 3 is the control variable for the light control system 1, the incidence (or decrease) of this extraneous light F L The lighting of work area A will be regulated in the same way as described above.

[0035] One possible scenario is that the light 2b of the adjacent workstation Ab is switched on, resulting in a direct light component L D and an indirect light component L I the adjacent luminaire 2b to suddenly illuminate the work surface 4 of the work area A and / or the ceiling D and to adjust the direct light components L using the light control system 1 D and the indirect light component L I The light 2 can be controlled as described above. This is particularly energy-saving when several adjacent work areas A are planned. Reference symbol list 1. Lighting control system 1.1 Light control 2 lights 2b light 3 light sensor 4 Assessment area 5.1 first light source 5.2 second light source 6 Underside 7 Top 8 LED 9 aperture a main radiation direction t time A work area From work area AF work surface AFb work surface The ceiling E v Illuminance E v ziel Target value F window F R Extraneous light window F L Ambient light source L D Direct light component L I Indirect light component L R Light component R space

Claims

[1] Method for regulating or controlling a luminaire (2) with direct and indirect light emission with respect to a work area (A) in a room (R) with ambient light (F F , F L ), such as daylight and / or light from other light sources influencing the work area, by means of a light control system (1) with the luminaire (2) and a light control unit (1.1) having a light sensor (3), with the process steps that by means of the light control system (1) with increasing exposure to extraneous light (F F , F L ) into the work area (A) first a dimming of the indirect light component (L I ) of the luminaire (2) and subsequently a dimming of the direct light component of the luminaire (2) and / or with decreasing ambient light (F F , F L ) into the work area, first a dimming up of the direct light component (L D) of the luminaire (2) and subsequently a dimming up of the indirect light component (L I ) of the light (2). [2] Method according to claim 1, characterized by , that with increasing exposure to extraneous light (F F , F L ) into the work area (A) dimming the direct light component (L I ) of the luminaire (2) by means of the light control system (1) only takes place after the indirect light component (L I ) the light emitted by the luminaire (2) was dimmed down to an illuminance of zero or nearly zero. [3] Method according to claim 1 or 2, characterized by , that with decreasing irradiance of extraneous light (F F , F L ) into the work area (A) the dimming up of the indirect light component (L I ) of the luminaire (2) by means of the light control system (1) only takes place after the direct light component (L D) the light emitted by the luminaire was dimmed up to a certain upper limit illuminance.

Images