Lighting systems, lighting methods, and programs

Abstract

This invention provides a lighting system that can estimate the illuminance in areas of an indoor space where ambient light is incident but no illuminance sensor is installed, by taking into account the direct light component of the ambient light. [Solution] The lighting system 10 controls the illuminance at a first position in an indoor space 70 to be within a target range, and includes an acquisition unit 45 that acquires date and time information indicating the current date and time, and illuminance information indicating the illuminance at a second position sensed by an illuminance sensor 30 installed at a second position in the indoor space 70, and a control unit 47 that controls the dimming rate of lighting fixtures 20 installed in the indoor space 70 so that the illuminance at the first position is within the target range based on the acquired date and time information and illuminance information.

Description

Technical Field

[0001] The present invention relates to a lighting system, a lighting method, and a program.

Background Art

[0002] Patent Document 1 discloses a control method for controlling the illuminance at a lighting required position by a lighting device with a configuration as inexpensive as possible.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention provides a lighting system or the like that can estimate the illuminance at a location where an illuminance sensor for indoor space where external light (daylight) is incident is not installed, taking into account the direct light component of the external light.

Means for Solving the Problems

[0005] A lighting system according to an aspect of the present invention is a lighting system that controls the illuminance at a first position in an indoor space within a target range, and includes an acquisition unit that acquires date and time information indicating the current date and time, and illuminance information indicating the illuminance at a second position sensed by an illuminance sensor installed at the second position in the indoor space, and a control unit that controls the dimming rate of a lighting fixture installed in the indoor space so that the illuminance at the first position estimated based on the acquired date and time information and the illuminance information is within the target range.

[0006] A lighting method according to one aspect of the present invention is a lighting method performed by a computer for controlling the illuminance at a first position in an indoor space to be within a target range, and includes an acquisition step of acquiring date and time information indicating the current date and time, and illuminance information indicating the illuminance at a second position sensed by an illuminance sensor installed at the second position in the indoor space, and a control step of controlling the dimming rate of a lighting fixture installed in the indoor space so that the illuminance at the first position estimated based on the acquired date and time information and the illuminance information falls within the target range.

[0007] A program according to one aspect of the present invention is a program for causing the computer to execute the lighting method. [Effects of the Invention]

[0008] The lighting system of the present invention can estimate the illuminance in a location in an indoor space where an illuminance sensor is not installed, taking into account the direct light component of the ambient light. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a block diagram showing the functional configuration of a lighting system according to an embodiment. [Figure 2] Figure 2 shows an example of the installation of multiple illuminance sensors. [Figure 3] Figure 3 is a flowchart of Operation Example 1 of the lighting system according to the embodiment. [Figure 4] Figure 4 is a flowchart of operation example 2 of the lighting system according to the embodiment. [Modes for carrying out the invention]

[0010] The embodiments will be described in detail below with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection configurations of components, steps, and the order of steps shown in the following embodiments are examples only and are not intended to limit the present invention. Furthermore, components in the following embodiments that are not described in an independent claim will be described as optional components.

[0011] Please note that each figure is a schematic diagram and not necessarily a strictly accurate representation. Furthermore, in each figure, substantially identical components are denoted by the same reference numerals, and redundant explanations may be omitted or simplified.

[0012] (Embodiment) [composition] First, the configuration of the lighting system according to the embodiment will be described. Figure 1 is a block diagram showing the functional configuration of the lighting system according to the embodiment.

[0013] The lighting system 10 is a system that can adjust the illuminance in areas of an indoor space 70 where no illuminance sensors 30 are installed to a target range, while taking into account the influence of ambient light (daylight). As described later, the lighting system 10 can adjust the illuminance in areas where no illuminance sensors 30 are installed using a relatively small number of illuminance sensors 30. In other words, the lighting system 10 is a low-cost system that requires a small number of illuminance sensors 30.

[0014] As shown in Figure 1, the lighting system 10 comprises a plurality of lighting fixtures 20, a plurality of illuminance sensors 30, a lighting control device 40, an information terminal 50, and a server device 60. The plurality of lighting fixtures 20, the plurality of illuminance sensors 30, the lighting control device 40, and the information terminal 50 are installed, for example, in or near the indoor space 70.

[0015] The lighting fixture 20 is a base light or the like, installed on the ceiling of the interior space 70 to illuminate the interior space. The form of the lighting fixture 20 is not particularly limited and may be a ceiling light, downlight, spotlight, etc. The lighting system 10 only needs to include at least one lighting fixture 20.

[0016] The interior space 70 is divided into multiple areas, and at least one lighting fixture 20 is installed in each of the multiple areas. For the sake of simplicity, in the following explanation, one lighting fixture 20 is installed in each area, and the term "multiple lighting fixtures 20" refers to multiple lighting fixtures 20 installed in different areas. If two or more lighting fixtures 20 are installed in the same area, these two or more lighting fixtures 20 are controlled to emit light at the same dimming rate, but they may also be controlled to emit light at different dimming rates.

[0017] The illuminance sensor 30 is installed on the ceiling or wall of the indoor space 70 and senses the illuminance (brightness) in the indoor space 70. The illuminance sensor 30 also transmits illuminance information, which indicates the illuminance sensing result, to the lighting control device 40. The lighting system 10 only needs to be equipped with at least one illuminance sensor 30.

[0018] Figure 2 shows an example of the installation of multiple illuminance sensors 30, and is a top view (floor plan) of the indoor space 70.

[0019] The illuminance sensor 30 is installed corresponding to, for example, the opening 71 of the indoor space 70. Here, the opening 71 means a place where outside light enters the indoor space 70, such as a window. In the example of FIG. 2, corresponding to the wall provided with three openings 71, three illuminance sensors 30 are installed on the ceiling near the wall. When there are three separated openings 71 in the indoor space 70, it is preferable that at least one illuminance sensor 30 is provided for each of the openings 71 in order to sense the degree of influence of outside light. That is, when there are three separated openings 71, it is preferable that at least three illuminance sensors 30 are provided. Note that the illuminance sensor 30 is installed at a position about 2 to 5 m away from the opening 71 so that the output fluctuation due to outside light does not become excessive.

[0020] In addition, since the illuminance sensor 30 is also a sensor for sensing the influence of the light emitted by the lighting fixture 20, it may be installed in a place where there is no opening 71. In the example of FIG. 2, further, corresponding to the wall where no opening 71 is provided, one illuminance sensor 30 is installed on the ceiling near the wall.

[0021] The lighting control device 40 receives the illuminance information transmitted by the illuminance sensor 30 and controls a plurality of lighting fixtures 20 based on the received illuminance information. The lighting control device 40 includes a first communication unit 41, an information processing unit 42, a storage unit 43, and a second communication unit 44.

[0022] The first communication unit 41 is a communication circuit for the lighting control device 40 to communicate with a plurality of lighting fixtures 20 and a plurality of illuminance sensors 30 via a local communication network. The first communication unit 41 is, for example, a wireless communication circuit that performs wireless communication, but may also be a wired communication circuit that performs wired communication. The communication standard of the communication performed by the first communication unit 41 is not particularly limited.

[0023] The information processing unit 42 performs information processing to control multiple lighting fixtures 20 based on illuminance information. The information processing unit 42 is implemented by, for example, a microcomputer, but may also be implemented by a processor. The information processing unit 42 has, as functional components, an acquisition unit 45, an estimation unit 46, and a control unit 47. The functions of the acquisition unit 45, the estimation unit 46, and the control unit 47 are realized, for example, by the microcomputer or processor constituting the information processing unit 42 executing a computer program stored in the storage unit 43.

[0024] The memory unit 43 is a storage device that stores the information necessary for the information processing described above. The information necessary for information processing includes, for example, a computer program executed by the information processing unit 42. The information necessary for information processing also includes influence information for estimating the illuminance at locations where the illuminance sensor 30 is not installed. The memory unit 43 is implemented, for example, by a semiconductor memory. Details of the influence information will be described later.

[0025] The second communication unit 44 is a communication circuit for the lighting control device 40 to communicate with a server device 60 or the like via a wide-area communication network 80. The second communication unit 44 is, for example, a wireless communication circuit for wireless communication, but it may also be a wired communication circuit for wired communication. There are no particular limitations on the communication standards used by the second communication unit 44.

[0026] The information terminal 50 is an information terminal used by designers of the lighting system 10 to perform simulations of illuminance in the indoor space 70. The information terminal 50 is a portable information terminal such as a notebook personal computer, but it may also be a stationary information terminal. Furthermore, the information terminal 50 may be an information terminal that can be operated remotely. The information terminal 50 comprises an operation reception unit 51, a display unit 52, an information processing unit 53, a storage unit 54, and a communication unit 55.

[0027] The operation reception unit 51 receives input from the designer or other user. The operation reception unit 51 is implemented, for example, by a mouse or keyboard, but may also be implemented by a touch panel.

[0028] The display unit 52 displays an image. The display unit 52 is implemented by a display panel such as a liquid crystal panel or an organic EL (Electro-Luminescence) panel.

[0029] The information processing unit 53 performs processing such as displaying an image on the display unit 52 in response to input received by the operation reception unit 51. The information processing unit 53 is implemented by, for example, a microcomputer, but may also be implemented by a processor. The information processing unit 53 includes a calculation unit 56 as a functional component. The function of the calculation unit 56 is realized, for example, by the microcomputer or processor constituting the information processing unit 53 executing a computer program stored in the storage unit 54.

[0030] The memory unit 54 is a storage device that stores computer programs executed by the information processing unit 53. The computer programs stored in the memory unit 54 include application programs for simulating the illuminance of the indoor space 70. The memory unit 54 is implemented, for example, by semiconductor memory.

[0031] The communication unit 55 is a communication circuit (communication module) for the information terminal 50 to communicate with the server device 60 via the wide-area communication network 80. The communication unit 55 is, for example, a wireless communication circuit for wireless communication, but it may also be a wired communication circuit for wired communication. There are no particular limitations on the communication standards used by the communication unit 55.

[0032] The server device 60 is a cloud server installed outside the indoor space 70. The lighting control device 40 can communicate with the server device 60 as needed to perform processing that requires cooperation with the server device 60, as described in the following example of operation. Note that it is not mandatory for the lighting system 10 to include the server device 60.

[0033] [Impact information] Designers of the lighting system 10 perform a simulation of the illuminance of the indoor space 70 in advance using the information terminal 50 and generate influence information. If the position in the indoor space 70 where the illuminance is to be adjusted to a target range and where the illuminance sensor 30 is not installed is defined as the first position, the influence information is information that shows the degree of influence of the light emitted by the multiple lighting fixtures 20 installed in the indoor space 70 on the illuminance at the first position, the degree of influence of the direct light component of the ambient light entering the indoor space 70 through the opening 71 of the indoor space 70, and the degree of influence of the sky light component of the ambient light.

[0034] Here, we will provide some additional information regarding the direct light component and the sky light component. The direct light component refers to the portion of sunlight (outdoor light) that reaches the indoor space 70 directly without being diffused or absorbed by water vapor, dust, etc. Since the direct light component fluctuates in relation to the altitude of the sun, it can be said to be a component that fluctuates greatly over time.

[0035] Skylight refers to the light that reaches the indoor space 70 after sunlight (outdoor light) has been scattered by dust, clouds, etc., as it passes through the atmosphere. The influence of the sun's altitude (time of day) on the skylight component is small, and it can be said that the skylight component is a component that fluctuates less over time compared to the direct light component.

[0036] The method for generating impact information is described below. Designers and others input information necessary for the simulation into the information terminal 50 by performing a predetermined first operation on the operation reception unit 51 of the information terminal 50. The information necessary for the simulation includes location information of the building constituting the indoor space 70 (including information such as latitude, longitude, height of the indoor space 70 from the ground, and orientation within the indoor space 70). The information necessary for the simulation also includes map information showing the shape and size of the indoor space 70 (floor plan information, such as Figure 2), information showing the installation locations of multiple lighting fixtures 20, information showing the location and size of one or more openings 71, information showing the first location mentioned above, information showing the installation locations of multiple illuminance sensors 30, information showing the installation locations of furniture, and information showing various reflectances of walls, floors, and ceilings. The information necessary for the simulation also includes information on other shading objects and other light-emitting objects (such as displays and monitors) installed in the indoor space 70. The simulation may include information about the surrounding environment of the building that constitutes the indoor space 70, or information about the buildings surrounding the building that constitutes the indoor space 70. Hereafter, the installation positions of the multiple illuminance sensors 30 will also be referred to as the second positions.

[0037] The simulation is performed assuming that a pseudo-emissive element with controllable dimming rate is installed at the position of aperture 71. In other words, in the simulation, the light emitted by the pseudo-emissive element is considered to be ambient light.

[0038] Assuming there are n first positions, m lighting fixtures 20 are installed, and p pseudo-light-emitting elements (apertures 71), the calculation unit 56 simulates the illuminance at each of the n first positions when the dimming rates of the m lighting fixtures 20 and the dimming rates of the p pseudo-light-emitting elements are varied. Based on the simulation results, it can calculate influence information (a group of coefficients that can be represented by a matrix, etc.) that shows the relationship between the illuminance at each of the n first positions, the dimming rates of the m lighting fixtures 20, and the dimming rates of the p pseudo-light-emitting elements. The influence information is information that shows, by coefficients, the degree of influence on the illuminance at the first position when the dimming rate of the lighting fixtures 20 is varied by a unit dimming rate, and the degree of influence on the illuminance at the first position when the dimming rate of the pseudo-light-emitting elements is varied by a unit dimming rate. The influence information can also be considered as a transfer function of light (luminous flux).

[0039] Here, the coefficients multiplied by the dimming rate of the pseudo-emissive material in the influence information are distinguished into a first coefficient that indicates the influence of the direct light component and a second coefficient that indicates the influence of the sky light component. As mentioned above, the direct light component fluctuates greatly depending on the date and time, so it is set to a different value depending on the date and time. On the other hand, since the sky light component fluctuates little depending on the date and time, the second coefficient is set to the same value regardless of the date and time.

[0040] In order to calculate the first coefficient, which differs for each condition, the simulation is performed multiple times, changing the date and time (more specifically, the conditions related to the sun's altitude, which change depending on the date and time), and the first coefficient will have a different value for each date and time. In other words, in the simulation, multiple sets of influence information with different values ​​for the first coefficient are calculated, and the date and time are associated with the influence information.

[0041] Furthermore, the calculation unit 56 performs a similar simulation not only for the first position but also for the second position where the illuminance sensor 30 is installed. If there are q second positions (illuminance sensors 30), the calculation unit 56 simulates the illuminance at each of the q second positions when the dimming rate of m lighting fixtures 20 and the dimming rate of p pseudo-light-emitting elements are varied. Based on the simulation results, it can calculate estimation information (a group of coefficients that can be represented by a matrix, etc.) that shows the relationship between the illuminance at each of the q second positions, the dimming rate of m lighting fixtures 20, and the dimming rate of p pseudo-light-emitting elements.

[0042] In the estimation data, the coefficients multiplied by the dimming rate of the pseudo-luminescent material are distinguished into a first coefficient, which indicates the degree of influence of the direct light component, and a second coefficient, which indicates the degree of influence of the sky light component. In order to calculate the first coefficient, which differs for each date and time, the simulation is performed in multiple ways, changing the date and time (more precisely, the conditions regarding the altitude of the sun, which change depending on the date and time), and the first coefficient will have a different value for each date and time. In other words, in the simulation, multiple estimation data sets with different values ​​for the first coefficient are calculated, and the date and time are associated with the estimation data.

[0043] Furthermore, impact information and estimation information may be generated by actually measuring illuminance in the indoor space 70 instead of using simulation. When measuring illuminance, a method may be used in which an image (photograph) of the indoor space 70 is taken using a camera, and the brightness distribution and illuminance distribution in the indoor space 70 are estimated by image processing of the captured image. In addition, impact information and estimation information may be generated by using a combination of simulation and actual measurement.

[0044] [Example of operation 1] Next, we will describe example 1 of the operation of the lighting system 10. Figure 3 is a flowchart of example 1 of the operation of the lighting system 10.

[0045] First, impact information, estimation information, and setting information are stored in the storage unit 43 of the lighting control device 40. The impact information, estimation information, and setting information are transmitted, for example, from the information terminal 50 to the lighting control device 40 and stored in the storage unit 43 (S11). The impact information, estimation information, and setting information may be stored in the storage unit 43 by manual input based on operations on the user interface (not shown) provided by the lighting control device 40, or they may be stored (copied) in the storage unit 43 by connecting a portable recording medium such as a USB memory to the lighting control device 40.

[0046] Here, we will explain the configuration information. Specifically, the configuration information concerns the control of multiple lighting fixtures 20. The configuration information specifies the target range of illuminance for each of the first positions, constraints in the control of the multiple lighting fixtures 20, the upper limit of the dimming rate of the lighting fixtures 20 in the control, and the lower limit of the dimming rate of the lighting fixtures 20 in the control. The configuration information is specified, for example, by the designer of the lighting system 10 or by the user of the indoor space 70. It is not mandatory for the configuration information to include all of this information; it is sufficient to include the necessary information as appropriate.

[0047] Next, the acquisition unit 45 acquires date and time information indicating the current date and time (month, day, and time) (S12). For example, the lighting control device 40 is equipped with a timekeeping unit such as a real-time clock, and the acquisition unit 45 acquires date and time information indicating the current date and time measured by the timekeeping unit. The acquisition unit 45 may also acquire date and time information from a time management server (not shown) by communicating with the time management server using the second communication unit 44.

[0048] Next, the acquisition unit 45 acquires (receives) illuminance information indicating the illuminance at the second location where the illuminance sensor 30 is installed from each of the multiple illuminance sensors 30 via the first communication unit 41 (S14).

[0049] Next, the estimation unit 46 identifies estimation information and influence information corresponding to the date and time information acquired in step S12 (S15). The estimation unit 46 identifies estimation information corresponding to the current date and time indicated by the acquired date and time information from among estimation information with different values ​​of the first coefficient indicating the influence of the direct light component, and identifies influence information corresponding to the current date and time indicated by the acquired date and time information from among influence information with different values ​​of the first coefficient.

[0050] The estimation unit 46 estimates the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space 70 based on calculation formula 2, which is determined by the acquired illuminance information and the identified estimation information (S16). The intensity of the direct light component and the sky light component of the ambient light incident on the indoor space 70 is expressed by the dimming rate of the pseudo-light-emitting element, and the estimation unit 46 estimates (calculates) the dimming rate of the pseudo-light-emitting element by substituting the illuminance indicated by the illuminance information acquired in step S14 into the calculation formula 2. In other words, the estimation unit 46 can estimate the intensity of the direct light component and the sky light component of the ambient light based on the illuminance indicated by the illuminance information acquired in step S14 and the estimation information stored in the storage unit 43 (more specifically, the estimation information identified in step S15).

[0051] Furthermore, the estimation unit 46 estimates the illuminance at each of the first positions (S17) based on the current dimming rates of the multiple lighting fixtures 20 managed in the storage unit 43 of the lighting control device 40, the respective intensities of the direct light component and the sky light component of the ambient light estimated in step S16, and a calculation formula 1 determined by the influence information identified in step S15. The estimation unit 46 can estimate the illuminance at each of the first positions by substituting the current dimming rates of the multiple lighting fixtures 20 and the respective intensities of the direct light component and the sky light component of the ambient light estimated in step S16 into the calculation formula 1.

[0052] Next, the control unit 47 determines whether all of the illuminances estimated in step S17 are within the target range defined in the setting information (S18). The target range is defined, for example, as within ±3% of a median of 750 lx, or within ±1% of a median of 500 lx.

[0053] If the illuminance estimated in step S17 is determined to be within the target range defined in the setting information (Yes in S18), the dimming rate of the multiple lighting fixtures 20 is not controlled, and the process in step S12 is performed again after a predetermined time has elapsed.

[0054] On the other hand, if the control unit 47 determines that at least one of the illuminances estimated in step S17 is outside the target range defined in the setting information (No in S18), it controls the dimming rate of at least one of the multiple lighting fixtures 20 so that all of the illuminances estimated in step S17 are within the target range (S19). After a predetermined time has elapsed, the process in step S12 is performed again.

[0055] In step S19, the control unit 47 calculates (searches) a dimming rate such that all illuminance at the first position falls within the target range by varying the dimming rate within a range that does not exceed the upper limit specified in the setting information and does not fall below the lower limit specified in the setting information, for example, in calculation formula 1 in which the intensity of the direct light component and the sky light component estimated in step S16 are substituted. The control unit 47 can control the dimming rates of the multiple lighting fixtures 20 to the calculated dimming rate by communicating with the multiple lighting fixtures 20 using the first communication unit 41.

[0056] The upper limit is, for example, 100%, and the lower limit is, for example, 5%, but is not particularly limited. Setting an upper limit allows for addressing situations where, due to a lighting design error, the dimming rate of the lighting fixture 20 must be set to a value exceeding the upper limit in order to bring the illuminance within the target range. Not setting the lower limit to 0% prevents the lighting fixture 20 from being turned off while it is lit, thus preventing user discomfort.

[0057] If the setting information specifies constraints for controlling the lighting fixture 20, the control unit 47 calculates a dimming ratio that satisfies the constraints specified in the setting information and ensures that all illuminances at the first position fall within the target range.

[0058] The constraint is, for example, that if there is a lighting fixture 20 that is turned off (dimming rate 0%), that lighting fixture 20 will not be turned on (it will be excluded from the control and its dimming rate will remain at 0%). The constraint may also be that the amount of change in the dimming rate (brightness of the area on the window side) of a lighting fixture 20 located closer to the opening 71 is greater than the amount of change in the dimming rate (brightness of other areas) of other lighting fixtures 20. This allows for an emphasis on energy conservation.

[0059] Furthermore, the constraint may be such that the difference in dimming rates between adjacent lighting fixtures 20 (adjacent areas) is within a threshold, thereby prioritizing user comfort. The constraint may also be such that a specific lighting fixture 20 is excluded from control, or it may be such that the amount of change in the dimming rate of each of the multiple lighting fixtures 20 is within 5% of the current dimming rate.

[0060] The combinations (patterns) of dimming rates of multiple lighting fixtures 20 and dimming rates of one or more pseudo-light-emitting elements used in the simulation to obtain the above calculation formula 1 are stored in a database in the storage unit 43, but may also be stored in the server device 60. In this case, in step S19, the control unit 47 can also calculate (search) a dimming rate such that all illuminance at the first position falls within the target range by referring to the database through communication with the server device 60 using the second communication unit 44.

[0061] As described above, the lighting system 10 acquires illuminance information indicating the illuminance at the second location, which is sensed by the illuminance sensor 30 installed at the second location in the indoor space 70, and estimates the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space 70 based on the acquired illuminance information. The lighting system 10 also acquires date and time information indicating the current date and time, and estimates the illuminance at the first location where the illuminance sensor 30 is not installed, based on the estimated intensity of the direct light component and the sky light component of the ambient light, the dimming rate of the lighting fixture 20, and the influence information corresponding to the current date and time indicated by the acquired date and time information, and controls the dimming rate of the lighting fixture 20 so that the estimated illuminance falls within the target range.

[0062] Such a lighting system 10 can adjust the illuminance in areas where no illuminance sensors 30 are installed, and does not require the installation of a large number of illuminance sensors 30. In other words, the lighting system 10 is a low-cost system that requires fewer illuminance sensors 30.

[0063] Furthermore, the lighting system 10 distinguishes between a direct light component and a sky light component of the ambient light incident on the indoor space 70, and by estimating the intensity of each component, it improves the accuracy of illuminance estimation and can adjust the illuminance to the target range more accurately. In lighting systems that do not consider the direct light component, the direct light component cannot be effectively utilized (the dimming rate of the lighting fixture 20 is increased as if there were no direct light component), but the lighting system 10 can effectively utilize the direct light component.

[0064] [Example of operation 2] In Operation Example 1, the estimation information was described as information showing the degree of influence of the direct sunlight component on the illuminance at the second location for each day and time. However, the estimation information may also be information showing the degree of influence of the direct sunlight component on the illuminance at the second location for each day and time, and for each weather condition. In other words, the simulation for calculating the estimation information may be performed by changing the day and time and the weather (e.g., four levels: clear, partly, cloudy, rainy). Similarly, the influence information was described as information showing the degree of influence of the direct sunlight component on the illuminance at the first location for each day and time. However, the influence information may also be information showing the degree of influence of the direct sunlight component on the illuminance at the first location for each day and time, and for each weather condition. In other words, the simulation for calculating the influence information may be performed by changing the day and time and the weather condition.

[0065] Below, we will describe Operation Example 2, where the estimation information and impact information are information that shows the impact of the direct light component for each date and weather condition. Figure 4 is a flowchart of Operation Example 2 of the lighting system 10. Below, we will explain the differences between Operation Example 2 and Operation Example 1.

[0066] First, the storage unit 43 of the lighting control device 40 stores the degree of influence information, estimation information, and setting information (S11). The acquisition unit 45 acquires date and time information indicating the current date and time (month, day, and time) (S12). The processing in steps S11 and S12 is the same as in operation example 1.

[0067] Next, the acquisition unit 45 acquires weather information indicating the current weather (S13). For example, the acquisition unit 45 acquires weather information (predicted information on the current weather) from a weather forecast information management server (not shown) by communicating with it using the second communication unit 44, or it may acquire weather information (actual information on the most recent weather) from a regional weather observation system (AMeDAS) by communicating with it using the second communication unit 44.

[0068] The acquisition unit 45 may also acquire weather information by estimating the weather from the illuminance sensor 30. The lighting system 10 is equipped with a camera that takes outdoor images of the surroundings of the indoor space 70, and the acquisition unit 45 may acquire weather information by estimating the weather from the images taken by the camera.

[0069] Next, the acquisition unit 45 acquires (receives) illuminance information indicating the illuminance at the second location where the illuminance sensor 30 is installed from each of the multiple illuminance sensors 30 via the first communication unit 41 (S14).

[0070] Next, the estimation unit 46 identifies estimation information and influence information that correspond to the date and time information acquired in step S12 and the weather information acquired in step S13 (S15). From among the estimation information with different values ​​of the first coefficient indicating the influence of the direct sunlight component, the estimation unit 46 identifies estimation information that corresponds to the current date and time indicated by the acquired date and time information and the weather indicated by the acquired weather information. The estimation unit 46 also identifies influence information that corresponds to the current date and time indicated by the acquired date and time information and the weather indicated by the acquired weather information from among the influence information with different values ​​of the first coefficient. The processing from step S16 onward is the same as in Operation Example 1.

[0071] According to the operation example 2 described above, the lighting system 10 can improve its estimation accuracy by taking weather conditions into consideration when estimating the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space 70.

[0072] [Differentiation] In the above embodiment, when the estimation unit 46 estimates the intensity of the direct light component of ambient light incident on the indoor space 70, it may perform a correction process after carrying out the process described in step S16 above, thereby correcting the estimated value of the direct light component.

[0073] For example, correction processing may be performed by comprehensively considering the measured values ​​of multiple illuminance sensors 30. For instance, when comparing the illuminance measured by the first illuminance sensor 30 with the illuminance measured by the second illuminance sensor 30, if the illuminance estimated from the illuminance measured by the first illuminance sensor 30 and measured by the second illuminance sensor 30 is clearly lower than the actually measured illuminance, it can be assumed that a large amount of direct light is incident on the first illuminance sensor 30. In such a case, the estimation unit 46 may perform a correction to increase the direct light component.

[0074] Furthermore, the estimation unit 46 stores the history of illuminance information obtained from each of the multiple illuminance sensors 30 in the storage unit 43, and based on the history of illuminance information, it can consider the component that changes over time as the direct light component and estimate the component that does not change over time as the sky light component. The estimation unit 46 may also use the first estimation result obtained by this estimation method to correct the second estimation result in step S16.

[0075] The estimation unit 46 identifies past conditions that closely resemble the current illuminance information conditions of the multiple illuminance sensors 30 based on the history of illuminance information. In the identified past conditions, it can consider components that fluctuate over time as direct light components and components that do not fluctuate over time as sky light components. The estimation unit 46 may use the first estimation result obtained by this estimation method to correct the second estimation result in step S16.

[0076] Furthermore, the opening 71 may be provided with an electric blind controlled by the control unit 47, or the window provided in the opening 71 may be a smart window (a window including a liquid crystal layer) whose light transmittance is controlled by the control unit 47. In this case, the control unit 47 may control the electric blind to a closed state or reduce the light transmittance of the smart window when the illuminance information obtained from the multiple illuminance sensors 30 is all higher than a predetermined value and the indoor space 70 is considered to be very bright (strong direct light). As a result, the lighting system 10 can reduce the amount of direct light in the indoor space 70 to within an acceptable range.

[0077] Furthermore, although it was explained in the above embodiment that the estimation information and the impact information are associated with the date and time, they may be associated with the altitude of the sun instead of the date and time, or in addition to the date and time. In this case, in step S15, the estimation unit 46 can estimate the altitude of the sun from the current date and time indicated by the date and time information, and identify the estimation information and impact information corresponding to the estimated altitude of the sun. Also, in this case, in step S12, information that directly indicates the altitude of the sun may be acquired instead of the date and time information, or in addition to the date and time information, and in this case, the process of estimating the altitude of the sun can be omitted. Information that directly indicates the altitude of the sun can be obtained from a weather forecast information management server (not shown) or other servers.

[0078] In the above embodiment, the lighting system 10 may control the dimming rate of at least some of the multiple lighting fixtures 20 so that the horizontal illuminance at the first position (such as ceiling illuminance or desk surface illuminance) is within the target range, or it may control the dimming rate of at least some of the multiple lighting fixtures 20 so that the vertical illuminance at the first position (such as facial illuminance) is within the target range. When the illuminance sensor 30 senses the horizontal illuminance, if it is desired that the vertical illuminance at the first position be within the target range, a conversion from horizontal illuminance to vertical illuminance may be performed as necessary.

[0079] Furthermore, in the above embodiment, some or all of the processing described as being performed by the lighting control device 40 may be performed by the server device 60. In other words, the server device 60 may include some or all of the acquisition unit 45, estimation unit 46, and control unit 47. Also, the simulation performed by the information terminal 50 may be performed by the lighting control device 40 or the server device 60. In other words, the lighting control device 40 or the server device 60 may include a calculation unit 56.

[0080] [Effects, etc.] The following describes examples of inventions that can be obtained from the disclosures in this specification, and explains the effects and other benefits that can be obtained from such inventions.

[0081] Invention 1 is a lighting system 10 for controlling the illuminance at a first position in an indoor space 70 to within a target range, comprising: an acquisition unit 45 that acquires date and time information indicating the current date and time, and illuminance information indicating the illuminance at a second position sensed by an illuminance sensor 30 installed at a second position in the indoor space 70; and a control unit 47 that controls the dimming rate of a lighting fixture 20 installed in the indoor space 70 so that the illuminance at the first position estimated based on the acquired date and time information and illuminance information falls within the target range.

[0082] Such a lighting system 10 can estimate the illuminance in areas of an indoor space where an illuminance sensor 30 is not installed, taking into account the direct light component of the ambient light (a component that varies depending on the time of day).

[0083] Invention 2 is a lighting system 10 of Invention 1, further comprising: a storage unit 43 that stores influence information indicating the degree of influence of the light emitted by the lighting fixture 20 on the illuminance at a first position, the degree of influence of the sky light component of the ambient light incident on the indoor space 70 through the opening 71 of the indoor space 70, and the degree of influence of the direct light component of the ambient light on the illuminance at the first position for each date and time; an estimation unit 46 that estimates the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space 70 based on the acquired illuminance information, and estimates the illuminance at the first position based on the estimated intensity of the direct light component and the sky light component, the dimming rate of the lighting fixture 20, and the influence information corresponding to the current date and time indicated by the acquired date and time information; and a control unit 47 that controls the dimming rate of the lighting fixture 20 so that the estimated illuminance is within the target range.

[0084] Such a lighting system 10 can adjust the illuminance at a first position in the indoor space 70 into which ambient light enters, where no illuminance sensor 30 is installed, to within a target range. Furthermore, the lighting system 10 can improve the accuracy of illuminance estimation at the first position compared to a lighting system that does not consider the direct light component of ambient light.

[0085] Invention 3 is a lighting system 10 of Invention 2, wherein the influence information shows the degree of influence of the direct light component on the illuminance at the first position for each date and weather condition, the acquisition unit 45 further acquires weather information indicating the current weather, and the estimation unit 46 estimates the illuminance at the first position based on the estimated intensity of the direct light component and the sky light component, the dimming rate of the lighting fixture 20, the current date and time indicated by the acquired date and time information, and the influence information corresponding to the current weather indicated by the acquired weather information.

[0086] Such a lighting system 10 can improve the accuracy of estimating illuminance at the first location by taking into account the current weather conditions.

[0087] Invention 4 is a lighting system 10 according to any of Inventions 1 to 3, further comprising a lighting fixture 20 and an illuminance sensor 30.

[0088] Such a lighting system 10 can be implemented as a system including a lighting fixture 20 and an illuminance sensor 30.

[0089] Invention 5 is a lighting method performed by a computer for controlling the illuminance at a first position in an indoor space 70 to be within a target range, and includes acquisition steps S12 and S14 for acquiring date and time information indicating the current date and time, and illuminance information indicating the illuminance at a second position sensed by an illuminance sensor 30 installed at a second position in the indoor space 70, and a control step S17 for controlling the dimming rate of a lighting fixture 20 installed in the indoor space 70 so that the illuminance at the first position estimated based on the acquired date and time information and illuminance information is within a target range.

[0090] This type of lighting method allows for the estimation of illuminance in areas of an indoor space where an illuminance sensor 30 is not installed, taking into account the direct light component of the ambient light (a component that varies depending on the time of day).

[0091] Invention 6 is a lighting method of Invention 5, wherein the computer has access to a storage unit 43, which stores influence information indicating the degree of influence of the light emitted by the lighting fixture 20 on the illuminance at a first position, the degree of influence of the sky light component of the ambient light incident on the indoor space 70 through the opening 71 of the indoor space 70, and the degree of influence of the direct light component of the ambient light on the illuminance at the first position for each date and time, and the lighting method further includes an estimation step S16 in which the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space 70 is estimated based on the acquired illuminance information, the dimming rate of the lighting fixture 20 and the influence information corresponding to the current date and time indicated by the acquired date and time information, and in a control step S17, the dimming rate of the lighting fixture 20 is controlled so that the estimated illuminance is within the target range.

[0092] This lighting method can adjust the illuminance at a first position in the indoor space 70 into which ambient light enters, where no illuminance sensor 30 is installed, to within a target range. Furthermore, this lighting method can improve the accuracy of illuminance estimation at the first position compared to lighting methods that do not consider the direct light component of ambient light.

[0093] Invention 7 is a program for causing a computer to execute the lighting method of Invention 5 or 6.

[0094] According to such a program, the computer can estimate the illuminance in areas of an indoor space where an illuminance sensor 30 is not installed, taking into account the direct light component of the ambient light (a component that varies depending on the time of day).

[0095] (Other embodiments) Although embodiments have been described above, the present invention is not limited to the embodiments described above.

[0096] For example, in the above embodiment, a process executed by a specific processing unit may be executed by another processing unit. Furthermore, the order of multiple processes may be changed, or multiple processes may be executed in parallel.

[0097] Furthermore, in the above embodiment, each component may be realized by executing a software program suitable for each component. Each component may also be realized by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0098] Furthermore, each component may be implemented by hardware. For example, each component may be a circuit (or integrated circuit). These circuits may form a single circuit as a whole, or they may be separate circuits. Also, each of these circuits may be a general-purpose circuit or a dedicated circuit.

[0099] Furthermore, general or specific embodiments of the present invention may be implemented as a system, apparatus, method, integrated circuit, computer program, or recording medium such as a computer-readable CD-ROM. Alternatively, they may be implemented as any combination of a system, apparatus, method, integrated circuit, computer program, and recording medium.

[0100] For example, the present invention may be implemented as a lighting system or lighting control device as described above, or as a method executed by a computer such as a lighting system or lighting control device. The present invention may be implemented as a program for causing a computer to execute such a method, or as a non-temporary recording medium on which such a program is recorded.

[0101] Furthermore, the present invention also includes forms obtained by applying various modifications to each embodiment that a person skilled in the art could conceive, or forms realized by arbitrarily combining the components and functions of each embodiment without departing from the spirit of the present invention. [Explanation of Symbols]

[0102] 10 Lighting Systems 20 Lighting fixtures 30 Illuminance Sensor 40 Lighting control device 41. First Communications Department 42 Information Processing Unit 43 Storage section 44. Second Communications Department 45 Acquisition Department 46 Estimation part 47 Control Unit 50 Information terminals 51 Operation reception unit 52 Display section 53 Information Processing Department 54 Storage section 55 Communications Department 56 Calculation Section 60 Server Devices 70 Indoor space 71 Opening 80 Wide-area telecommunications network

Claims

1. A lighting system that controls the illuminance at a first position in an indoor space to within a target range, An acquisition unit that acquires date and time information indicating the current date and time, and illuminance information indicating the illuminance at the second location sensed by an illuminance sensor installed at the second location in the indoor space, The system includes a control unit that controls the dimming rate of lighting fixtures installed in the indoor space so that the illuminance at the first position, estimated based on the acquired date and time information and illuminance information, falls within the target range. Lighting system.

2. moreover, A storage unit stores influence information that shows the degree of influence of the light emitted by the lighting fixture on the illuminance at the first position, and the degree of influence of the sky light component of the ambient light incident into the indoor space through the opening of the indoor space, and also shows the degree of influence of the direct light component of the ambient light on the illuminance at the first position for each day and time. The system includes an estimation unit that estimates the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space based on the acquired illuminance information, and estimates the illuminance at the first position based on the estimated intensity of the direct light component and the sky light component, the dimming rate of the lighting fixture, and the influence information corresponding to the current date and time indicated by the acquired date and time information. The control unit controls the dimming rate of the lighting fixture so that the estimated illuminance falls within the target range. The lighting system according to claim 1.

3. The influence information indicates the degree of influence of the direct light component on the illuminance at the first location, for each date and weather condition. The aforementioned acquisition unit further acquires weather information indicating the current weather, The estimation unit estimates the illuminance at the first location based on the estimated intensities of the direct light component and the sky light component, the dimming rate of the lighting fixture, the current date and time indicated by the acquired date and time information, and the influence information corresponding to the current weather indicated by the acquired weather information. The lighting system according to claim 2.

4. Furthermore, the lighting fixture and the illuminance sensor are provided. A lighting system according to any one of claims 1 to 3.

5. A lighting method, performed by a computer, that controls the illuminance at a first position in an indoor space to within a target range, An acquisition step of acquiring date and time information indicating the current date and time, and illuminance information indicating the illuminance at the second location sensed by an illuminance sensor installed at the second location in the indoor space, The control step includes controlling the dimming rate of lighting fixtures installed in the indoor space so that the illuminance at the first position, estimated based on the acquired date and time information and illuminance information, falls within the target range. lighting method.

6. The aforementioned computer has access to its storage unit, The storage unit stores influence information indicating the degree of influence of the light emitted by the lighting fixture on the illuminance at the first position, the degree of influence of the sky light component of the ambient light incident on the indoor space through the opening of the indoor space, and the degree of influence of the direct light component of the ambient light on the illuminance at the first position for each date and time. The lighting method further includes an estimation step of estimating the intensity of the direct light component and the sky light component of the ambient light incident on the indoor space based on the acquired illuminance information, and estimating the illuminance at the first position based on the estimated intensity of the direct light component and the sky light component, the dimming rate of the lighting fixture, and the influence information corresponding to the current date and time indicated by the acquired date and time information. In the control step, the dimming rate of the lighting fixture is controlled so that the estimated illuminance falls within the target range. The illumination method according to claim 5.

7. A program for causing the computer to execute the lighting method described in claim 5 or 6.

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