Lighting control method and lighting control system

Abstract

This invention provides a lighting control method comprising the following steps: receiving an image of a lighting field, wherein the lighting field comprises a plurality of sub-regions and each sub-region comprises at least one light source; analyzing the number of targets and the current illuminance in each sub-region based on the image; for each sub-region, calculating a predetermined illuminance based on the number of targets in this sub-region, the number of targets in another adjacent sub-region, and the distance of this sub-region relative to the other adjacent sub-region; and calculating the emission output value of the light source based on the difference between the predetermined illuminance and the current illuminance in each sub-region. This invention also provides a lighting control system comprising an analysis module for performing the aforementioned lighting control method, an optical sensor for acquiring an image of the lighting field, a plurality of light sources disposed in the lighting field, and a control module for controlling the output of the light sources.

Description

[Technical Field]

[0001] This invention relates to a lighting control method and a lighting control system for implementing the same. Specifically, this invention relates to a lighting control method that integrates consideration of different factors and a lighting control system for implementing the same. [Previous Technology]

[0002] With the development of smart buildings and energy-saving technologies, modern lighting control technology has gradually evolved from traditional manual or timed switching to intelligent lighting control systems that integrate environmental sensors and logic algorithms. These systems are widely used in office spaces, commercial areas, public facilities, and residences. Common practices include using infrared or sound sensors to detect human movement and turn on lighting, using ambient light sensors to turn on streetlights at night, and using reservation systems to turn on conference room lighting at set times.

[0003] However, existing smart lighting control technologies still have several limitations and areas for improvement in practical applications. For example, the sensing accuracy of human body sensors or ambient light sensors is limited, making it impossible to accurately grasp the distribution of people and light in different areas of a space. Furthermore, current technologies lack logic for lighting distribution and brightness level control, often resulting in a large number of lights being turned on or off simultaneously, leading to excessive ineffective lighting and energy waste. In addition, current technologies rarely consider visual comfort in their design, which may result in excessively rapid brightness adjustment rates or obvious bright-dark boundaries in the space, causing visual fatigue for users.

[0004] Therefore, there is a need to develop an improved smart lighting control method that can instantly grasp the distribution of people in the space, ambient light conditions or other considerations, and make dynamic adjustments in accordance with human needs to improve lighting quality, visual comfort and overall energy efficiency. [Summary of the Invention]

[0005] One objective of this invention is to provide a lighting control method that uses intelligent image analysis technology to obtain information such as personnel distribution and ambient brightness in real time to adjust relevant lighting control factors, dynamically adjust the light source output, thereby improving lighting quality and reducing energy waste from ineffective lighting.

[0006] One objective of this invention is to provide a lighting control method that utilizes intelligent image analysis technology to adjust the light source output based on the distribution of people and the ambient illuminance, thereby ensuring visual comfort and adjusting the lighting to reduce situations where brightness changes too quickly or the boundary between light and dark is obvious.

[0007] Another objective of the present invention is to provide a lighting control system for acquiring spatial images and analyzing the optimal lighting configuration based on information such as the distribution of people and ambient brightness in the images, thereby controlling the light source to meet the corresponding output requirements, so as to achieve the purpose of intelligent lighting control.

[0008] The lighting control method is applied to a lighting field, the lighting field comprising a plurality of sub-regions, and each sub-region comprising at least one light source. The lighting control method comprises the following steps: receiving an image of the lighting field; analyzing the number of targets and the current illuminance in each sub-region based on the image; for each sub-region, calculating a predetermined illuminance based on the number of targets in the sub-region, the number of targets in another adjacent sub-region, and the distance of the sub-region relative to the other adjacent sub-region; and calculating the luminous output value of the light source based on the difference between the predetermined illuminance and the current illuminance in each sub-region.

[0009] On the other hand, the lighting control system includes an analysis module, an optical sensor, multiple light sources, and a control module. The analysis module executes the aforementioned lighting control method and sends operation messages containing luminous output values. The optical sensor is signal-connected to the analysis module and is used to acquire images of the lighting field and transmit them to the analysis module. Light sources are placed in the lighting field. The control module is signal-connected to the analysis module and to the light sources. The control module receives operation messages and controls each light source to adjust its brightness according to the corresponding luminous output value.

Implementation Method

[0026] Various embodiments will be described below, and those skilled in the art should be able to easily understand the spirit and principles of the invention by referring to the description and accompanying drawings. However, although some specific embodiments will be specifically described herein, these embodiments are merely illustrative and are not to be considered limiting or exhaustive in any respect. Therefore, various changes and modifications to the invention will be obvious and easily achievable by those skilled in the art without departing from the spirit and principles of the invention.

[0027] In the accompanying drawings, the thicknesses of layers, films, panels, regions, etc., are enlarged for clarity. The relative dimensions of the elements in the drawings are illustrative only and are not intended to limit the invention. The embodiments described herein should not be construed as limited to the specific shapes of the regions shown in the drawings; for example, regions shown or described as flat may generally have rough and / or non-linear characteristics. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected" to another element, it may be directly on or connected to the other element, or intermediate elements may also be present. Conversely, when an element is referred to as being "directly on" or "directly connected to" another element, no intermediate elements are present. As used herein, "connection" can refer to physical and / or electrical connection. Furthermore, "electrical connection" or "electrical coupling" indicates that intermediate elements may be present.

[0028] Throughout this specification, the same component symbols denote the same components. It should be understood that although the terms "first," "second," "third," etc., may be used herein to describe various components, parts, regions, layers, and / or portions, these components, regions, and / or portions should not be limited by these terms. These terms are used only to distinguish one component, part, region, layer, or portion from another. Therefore, "first element," "first component," "first region," "first layer," or "first part" discussed below may be referred to as a second element, part, region, layer, or portion without departing from the teachings herein.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not restrictive. As used herein, unless the content clearly indicates otherwise, the singular forms "a," "an," and "the" are intended to include the plural forms, including "at least one." "Or" means "and / or." As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It should also be understood that, when used in this specification, the terms "comprising" and / or "including" specify the presence or addition of the stated features, areas, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, areas, integrals, steps, operations, elements, components, and / or combinations thereof.

[0030] Figure 1 shows a simplified flowchart of a lighting control method in one embodiment. The lighting control method is applied to a lighting field, which includes multiple sub-areas, and each sub-area includes at least one light source. The lighting control method includes the following steps S1 to S4. Step S1 is to receive an image of the lighting field. The image can be obtained by an optical sensor such as a camera, and the division of sub-areas can be adjusted as needed. Step S2 is to analyze the number of targets and the current illuminance in each sub-area based on the image, wherein the definition of targets can be determined according to the type of the field or lighting requirements. For example, when the lighting field is an office, the target can be set as a person, or when the lighting field is a parking lot, the target can include people and vehicles, but is not limited thereto. Step S3 is a predetermined illuminance calculation step for each sub-area, which can be calculated based on the number of targets in this sub-area, the number of targets in one or more neighboring sub-areas, and the distance of this sub-area relative to the neighboring sub-areas. In other words, the predetermined illuminance of each sub-region is not only related to the number of targets in its own sub-region, but also to the number of targets in neighboring sub-regions, and the distance between the two sub-regions is also taken into consideration. Step S4 is the calculation step for the luminous output value of each light source, which can be calculated based on the difference between the predetermined illuminance and the current illuminance in each sub-region. After receiving the information containing the luminous output value, the light sources in each sub-region can adjust their brightness accordingly to make the illuminance of each sub-region tend towards the predetermined illuminance.

[0031] Figure 2 shows a schematic diagram of a lighting control system for performing a lighting control method. The lighting control system includes an optical sensor 100, an analysis module 200, a control module 300, and multiple light sources 400. The optical sensor 100 is disposed in the lighting field 1 and signal-connected to the analysis module 200 to acquire an image 101 of the lighting field 1 and transmit it to the analysis module 200. The optical sensor 100 may include, but is not limited to, a directional camera, a 360-degree panoramic camera, an infrared detector, an illuminance sensor, or a combination thereof. After receiving the image 101, the analysis module 200 continues to execute the lighting control method as described above and issues an operation message 201 containing the emission output values ​​of the light sources in each sub-area. The control module 300 is configured to signal-connect to the analysis module 200 and the light sources 400 to receive the operation message 201 and control each light source to adjust its brightness according to the corresponding emission output value. The control module 300 can output corresponding signals to each sub-area, for example, outputting the first signal 301A and the second signal 301B to sub-area 10A and sub-area 10B respectively. When a sub-area contains multiple light sources 400 (for example, sub-area 10A contains two light sources 400), it can control each light source to emit the same brightness, or it can adjust the brightness of each light source to be different according to the different luminous efficiencies or usage states of the light sources.

[0032] The steps of the lighting control method will be explained below. As shown in Figure 3, after acquiring the image in step S1, the corresponding lighting field 1 can be divided into multiple sub-areas 10 according to the planar coordinates of the image. The lighting field 1 can be, for example, a conference room, and can be divided into two-dimensionally arranged multi-cell sub-areas 10. By defining the sub-areas 10 using the planar coordinates of the image, a computational model can be quickly established so that the lighting control method can be applied to different fields. On the other hand, the sub-areas 10 can be divided according to the objects or boundaries of entities in the lighting field 1 (not shown in the figure), for example, dividing each seat into different sub-areas 10 or dividing the sub-areas 10 according to the position of each light source. By defining the sub-areas 10 according to the actual scene, the actual personnel distribution pattern or the illumination range of the light source can be reflected. After defining the range of the sub-areas 10 using the first captured image, the same definition can be used for the analysis of the same lighting field 1.

[0033] Regarding the image analysis in step S2, artificial intelligence technology can be used to identify the location of the target H (e.g., a human body or face) in the image, and then determine which sub-region 10 the target H is located in. When the target H is located in multiple sub-regions 10 at the same time, the sub-region 10 where the target is located can be determined based on factors such as the size of the area occupied by the target in each sub-region 10 or the position of the target's head, or the target H can be included in multiple sub-regions 10. In addition, the current illuminance of each sub-region 10 can be determined based on the color brightness in the image. Specifically, a standard image with known illuminance can be taken first as a benchmark for subsequent illuminance comparison. For example, in the absence of ambient light, the light source can be turned on to standard brightness (e.g., maximum brightness) to take a standard image with standard illuminance (e.g., defined as working illuminance); or, standard images can be taken under different lighting conditions, and illuminance meters can be set in the lighting field 1 to measure the illuminance of each sub-region 10 (one or more locations can be measured in a sub-region 10) to establish the correspondence between the standard image and the actual illuminance. Using the above method, the number of targets and the current illuminance in each sub-region 10 can be obtained.

[0034] The aforementioned images can be one or more. For example, in a large lighting field or one with obstructions, two or more optical sensors can be set to capture the entire lighting field, or a single optical sensor can capture multiple images from different perspectives. As shown in the lighting field 1 in Figure 4, optical sensors 100A and 100B are used to capture partition images 101A and 101B, respectively, and partition images 101A and 101B partially overlap. For the sub-region 10V corresponding to the overlapping part, the number of targets and the current illuminance of the sub-region can be calculated based on partition images 101A and 101B, respectively. Since the clarity and color of different images vary, different analysis results for the number of targets or the current illuminance of the same sub-region may be generated, so it is necessary to establish selection rules. For example, in step S2, the number of targets in sub-region 10V can be set to the largest among the number of targets in the partition, and its current illuminance can be set to the smallest among the current illuminances of the partition. This setting ensures that the selected number of targets and the current illuminance will calculate a larger predetermined illuminance, avoiding insufficient lighting due to errors in parameter analysis in the image.

[0035] Regarding step S3, namely the predetermined illuminance calculation step, the target illuminance of each sub-area can be calculated based on the number of targets in each sub-area and the number of targets in neighboring sub-areas, weighted by the distance between the sub-areas. Figure 5 shows a flowchart of step S3 in one embodiment. First, a sub-area is selected, and it is determined whether the number of targets in this sub-area reaches a preset threshold value. The threshold value can be determined according to different needs. For example, a threshold value of 1 can be set to distinguish between sub-areas with or without people. The threshold value can also be set to other values ​​to correspond to different needs, and the threshold value is not limited to one or more. For example, the threshold value can include a series of values ​​from small to large, and each corresponds to a different predetermined illuminance from weak to strong. In this embodiment, when the number of targets in a sub-area is greater than or equal to the threshold value, the sub-area is defined as being in a working state, so the predetermined illuminance is set as the working illuminance, such as 500 lux. Conversely, when the number of targets is less than the threshold value, the sub-area is defined as being in a background state, and the predetermined illuminance of this sub-area can be calculated based on the number of targets in neighboring sub-areas and the distance between the two sub-areas. In other words, when there are people in the neighboring sub-area, the illuminance of the background sub-area can be increased to supplement the lighting of the neighboring sub-area and avoid creating obvious bright-dark boundaries.

[0036] Specifically, the more nearby targets there are, or the shorter the distance to the sub-area in the working state, the higher the predetermined illuminance of the sub-area in the background state. Figure 6 shows a schematic diagram of the predetermined illuminance distribution calculated according to the method in Figure 5. In sub-area 10A, a target H is detected, and the target quantity is 1, which is judged as a working state where the target quantity is greater than a threshold value (e.g., the threshold value is set to 1); at the same time, the target quantity in the surrounding sub-areas 10B and 10C is 0, which is judged as a background state where the target quantity is less than a threshold value. The predetermined illuminance of sub-area 10A in the working state is the highest, while sub-area 10B, which is closer to sub-area 10A, has a medium predetermined illuminance, and sub-area 10C, which is farther away from sub-area 10A, has the lowest predetermined illuminance. By setting this up, an illuminance distribution centered on the sub-area in the working state and decreasing outward can be achieved, avoiding users in the central sub-area from experiencing obvious bright and dark boundaries. In addition, when the coverage of a light source in a sub-region is narrow, light sources in neighboring sub-regions can provide supplementary illumination to improve the uniformity of illumination in the sub-region.

[0037] In one embodiment, the predetermined illuminance of a sub-region in the background state can be the sum of the product of the number of targets, distance weight, and supplementary illuminance of one or more neighboring sub-regions, calculated, for example, with reference to the following formula: Ej = max (E0 , ∑wi ei), where Ej is the predetermined illuminance of the j-th sub-region; E0 is the illuminance background value, i.e., the minimum illuminance required for the illumination field; ∑wi ei represents the sum of weighted supplementary illuminance, i can be an integer from 1 to N, and N is the total number of sub-regions in the illumination field; wi is the supplementary light weight of the i-th sub-region, which is related to the distance of the i-th sub-region relative to the j-th sub-region, and the shorter the distance, the larger wi is; ei is the supplementary illuminance corresponding to the i-th sub-region, which is related to the number of targets in the i-th sub-region, and the more targets, the larger ei is.

[0038] In other words, the predetermined illuminance (Ej) can be the sum of the weighted supplementary illuminances (∑ wi ei) of each sub-zone in the lighting area, but it must not be lower than the background illuminance value (E0). For example, the background illuminance value (E0) can be set to 50 lux, so that the sub-zones in the background state still provide weak lighting when no one is nearby, in order to achieve the required lighting atmosphere and improve safety. Depending on the type of area, the background illuminance value (E0) can also be set to 0 or other values.

[0039] Continuing with the above formula, wi is the supplementary lighting weight of the i-th sub-region, which is related to the distance between the i-th sub-region and the j-th sub-region; the shorter the distance, the larger wi is. ei is the supplementary illuminance contributed by the i-th sub-region, which is related to the number of targets in the i-th sub-region and can be set according to the type of the lighting field. For example, in the lighting field shown in Figure 6, the supplementary lighting weight (wi) of the adjacent first-layer sub-regions (not limited to edge-to-edge or corner-to-corner, such as sub-region 10A relative to sub-region 10B) can be set to 0.6, the supplementary lighting weight (wi) of the second-layer sub-regions (such as sub-region 10A relative to sub-region 10C) to 0.4, and the supplementary lighting weight (wi) of the third-layer or more distant sub-regions (not shown) to 0. Furthermore, the supplementary illuminance (ei) contributed by sub-regions with 1, 2, and 3 targets can be set to increase incrementally, for example, 400, 450, and 500 lux respectively. Therefore, when calculating the predetermined illuminance (Ej) of sub-zone 10B, the weighted supplementary illuminance contributed by the adjacent sub-zone 10A must be considered. This is the product of the supplementary lighting weight of the first-layer sub-zone (wi = 0.6) and the supplementary illuminance contributed by the sub-zone with one target (ei = 400) (i.e., 240 lux). Since the other sub-zones have zero targets, they contribute no supplementary illuminance. Therefore, the predetermined illuminance (Ej) of sub-zone 10B is equal to 240 lux. On the other hand, the predetermined illuminance (Ej) of sub-zone 10C is equal to the product of the supplementary lighting weight of sub-zone 10A (wi = 0.4 for the third-layer sub-zone) and the supplementary illuminance contributed by sub-zone 10A (ei = 400 for the sub-zone with one target), which is 160 lux. Using this method, the predetermined illuminance of each sub-zone can be determined based on the number and distribution of targets in the lighting field, providing precise lighting to meet the user's needs.

[0040] In different lighting environments, formulas or parameters can be adjusted to achieve the desired lighting mode. For example, the correspondence between supplementary lighting weight and distance can be adjusted according to the shape and distribution of the sub-area, such as defining the supplementary lighting weight by the distance between the center points of the sub-area; or, an upper limit value of the predetermined illuminance of the sub-area in the background state can be further set, such as 80% of the predetermined illuminance in the working state. The above formulas and parameters are merely examples of some embodiments of the present invention and are not intended to limit the scope.

[0041] Regarding the calculation of the light output value in step S4, the predetermined illuminance of each sub-region can be compared with the current illuminance to calculate the light output value of the light source in this sub-region. If the current illuminance is less than the predetermined illuminance, the light output value is reduced so that the adjusted illuminance reaches the predetermined illuminance; conversely, if the current illuminance is greater than the predetermined illuminance, the light output value is reduced. The light output value can take different forms, such as, but not limited to, a relative ratio (e.g., 0 to 100%) or a series of values ​​(e.g., 0 to 10). Among them, a light output value of 100% can correspond to the highest brightness of the light source, or it can be set to the brightness corresponding to the working illuminance, but it is not limited to this. The dimming mode of the light source can include, but is not limited to, pulse-width modulation (PWM), digital addressable lighting interface (DALI), and analog voltage control (e.g., 0–10V control mode). Depending on the dimming mode, the control module can convert the luminous output value into the required circuit signal (such as voltage or switching frequency) and transmit it to the light source in each sub-zone to control its brightness. After completing step S4, the next round of lighting control can begin again from step S1. The interval between each round can be adjusted according to the frequency of target movement in the lighting field, for example, but not limited to, 1 to 30 seconds. By recursively executing the above lighting control method, the current illuminance in the sub-zone can gradually approach the predetermined illuminance.

[0042] As shown in Figure 7, the lighting control method of the present invention may further include a lighting uniformity adjustment step S5, which can be followed by the predetermined illuminance calculation step S3 of the aforementioned embodiment. First, a sub-area in the lighting field is selected (step S51), and it is determined whether the number of targets in this sub-area reaches a preset threshold value (step S52). If the number of targets is greater than or equal to the threshold value, the lighting uniformity is calculated (step S53 is performed); otherwise, if the number of targets is less than the threshold value, the lighting uniformity is not calculated, and the process proceeds directly to the next step (e.g., step S4). In the lighting uniformity calculation step S53, the association set of this sub-area is defined to include this sub-area and one or more neighboring sub-areas. Then, the lighting uniformity is calculated based on the current illuminance of each sub-area in the association set. The association set can be determined by considering the range of obvious brightness changes that the user can perceive, and it can be some or all sub-areas in the lighting field. The lighting uniformity can be calculated based on statistical parameters such as the maximum, minimum, or average value of the current illuminance in the association set. Next, for each sub-region in the associated set, an illuminance adjustment rate is set based on the illumination uniformity and the current illuminance (step S54). Finally, based on the illuminance adjustment rate of each sub-region, the predetermined illuminance obtained in the previous step (e.g., step S3) is adjusted (step S55).

[0043] For example, the left and right images of Figure 8 show the current illuminance distribution of each sub-region in the associated set and the predetermined illuminance distribution after applying the illumination uniformity adjustment step, respectively. To focus on the explanation of the illumination uniformity adjustment step, it is assumed that the current illuminance of each sub-region in this embodiment matches the predetermined illuminance obtained in a previous step (e.g., step S3). When the illumination uniformity in the right image is too low, the predetermined illuminance of the brightest sub-region 10A can be reduced, and the predetermined illuminance of the darkest sub-region 10C can be increased to improve illumination uniformity. The adjusted predetermined illuminance distribution is shown in the left image. By this method, the illumination uniformity of the sub-regions surrounding the user can be improved, thereby enhancing the user's visual comfort.

[0044] Regarding the lighting uniformity calculation step S53, the size of the association set is related to factors such as the type of lighting field, the area of ​​the sub-area, and the user's action pattern. For example, for smaller areas such as conference rooms, the association set can be set to all sub-areas; while for larger areas such as parking lots or areas with many obstructions, the association set can be set to the selected sub-area and the sub-areas one or two layers above it. For example, in the embodiment shown in Figure 8, the target number of sub-area 10A is 1, and its association set includes a 5x5 array centered on sub-area 10A, but is not limited thereto. In addition, the lighting uniformity of the association set may include a first lighting uniformity, which is defined as the ratio of the minimum to the average current illuminance in each sub-area to reflect visually dark areas; or, the lighting uniformity may include a second lighting uniformity, which is defined as the ratio of the minimum to the maximum current illuminance in each sub-area to reflect the visual difference between light and dark.

[0045] The illuminance adjustment rate setting step S54 is further explained with reference to FIG9. First, for an associated set, it is determined whether the lighting uniformity reaches a preset lighting uniformity threshold, wherein the lighting uniformity threshold can be set according to the lighting field and purpose. For example, when giving a presentation in a conference room, a higher lighting uniformity is required to avoid visual fatigue, and the lighting uniformity threshold can be set to 0.8; or, in areas with low visual focus, such as halls or corridors, a lower lighting uniformity (e.g., 0.5) can be set to save energy. When the lighting uniformity is greater than or equal to the lighting uniformity threshold, it means that the lighting uniformity in the associated set meets the requirements, so the illuminance adjustment rate of each sub-area in the associated set is set to 1, that is, the predetermined illuminance is not adjusted. Conversely, when the lighting uniformity is less than the lighting uniformity threshold, it means that the predetermined illuminance needs to be adjusted to improve the lighting uniformity, so for the sub-area with the largest current illuminance, its illuminance adjustment rate is defined to be less than 1 (e.g., 0.9), and for the sub-area with the smallest current illuminance, its illuminance adjustment rate is defined to be greater than 1 (e.g., 1.1). The illuminance adjustment rate can be determined based on the difference between the illumination uniformity and the illumination uniformity threshold. The larger the difference, the more the illuminance adjustment rate deviates from 1.

[0046] Referring to FIG10, the predetermined illuminance adjustment step S55 is further explained. First, a sub-region in the associated set is selected, and it is determined whether the number of targets in this sub-region reaches a preset threshold value (e.g., the number of targets is at least 1). If the number of targets is greater than or equal to the threshold value, it indicates that this sub-region is in a working state, and its predetermined illuminance adjustment method can correspond to a preset working illuminance threshold (e.g., 450 lux); conversely, if the number of targets is less than or equal to the threshold value, it indicates that this sub-region is in a background state, and its predetermined illuminance adjustment method can correspond to a preset background illuminance threshold (e.g., 50 lux). The above threshold can be set according to the type of lighting field. Next, for the sub-region in the working state, it is determined whether the product of its predetermined illuminance and illuminance adjustment rate reaches the working illuminance threshold. If the product is greater than or equal to the working illuminance threshold, the adjusted predetermined illuminance is the original predetermined illuminance and illuminance adjustment rate; if the product is less than the working illuminance threshold, the adjusted predetermined illuminance is the working illuminance threshold. Similarly, for sub-zones in background mode, the background illuminance threshold is used as the comparison benchmark. In other words, the minimum adjusted predetermined illuminance values ​​for sub-zones in working mode and background mode are the working illuminance threshold and the background illuminance threshold, respectively. By setting this, the lighting uniformity of the area around the user can be improved while maintaining the basic illuminance of each sub-zone.

[0047] In one embodiment, the lighting control method may further include a lighting compensation step, which provides compensatory lighting for areas lacking available light sources. In the lighting field, when blocks are divided by image coordinates or physical boundaries, some blocks may not have light sources or may have light source malfunctions. In this case, the brightness of nearby available light sources can be increased so that areas lacking available light sources have appropriate illuminance. As shown in Figure 11, the lighting compensation step includes steps M1 to M3. Step M1 is to determine the subordinate area. First, the lighting field is divided into multiple blocks according to preset rules. One block is selected. If there is an available light source, this block is defined as a sub-area. If there is no available light source (including no light source is set or all light sources are in a disabled state, such as, but not limited to, light sources being disabled due to load balancing factors, light source malfunctions, etc.), this block is defined as a subordinate area. For the same lighting field, the determination of sub-areas and subordinate areas only needs to be performed once. After that, the determination result can be used. If the state of the light source changes, it must be re-determined. The lighting control method for sub-areas has been described in the foregoing embodiments (e.g., Figure 1) and will not be repeated here. Next, for the subordinate area, step M2 is performed. Based on the number of targets and current illuminance in the subordinate area analyzed in step S1, the compensated illuminance of the subordinate area is calculated. Finally, step M3 adjusts the luminous output value of the sub-area adjacent to the subordinate area according to the compensated illuminance, so that the current illuminance of the subordinate area approaches the required illuminance. In terms of operation sequence, step M3 can be arranged after the step of calculating the luminous output value of the sub-area (i.e., step S4 in Figure 1) to make adjustments based on the luminous output value of the previous step.

[0048] Referring to Figure 12, the compensation illuminance calculation step M2 is further explained. First, when the number of targets in the auxiliary area is greater than or equal to the threshold value, the auxiliary area is in working condition; if the number of targets is less than the threshold value, no compensation lighting is required, and the compensation illuminance is set to 0. Next, the current illuminance of the auxiliary area in working condition is compared with the preset working illuminance. If the current illuminance is less than the working illuminance, the compensation illuminance is set to the difference between the working illuminance and the current illuminance; if the current illuminance is greater than or equal to the working illuminance, no compensation lighting is required, and the compensation illuminance is set to 0. In the subsequent luminous output value adjustment step M3, for the neighboring sub-areas of the auxiliary area with a compensation illuminance greater than 0 (e.g., sub-areas adjacent to the auxiliary area), the luminous output value can be increased to provide indirect lighting to the auxiliary area. When the compensation illuminance of the auxiliary area is 0, the luminous output value of the neighboring sub-areas is not adjusted.

[0049] Figure 13 shows a schematic diagram of the lighting field including the auxiliary area. In this embodiment, sub-areas 10A and 10C each have a usable light source, while the light source in auxiliary area 10B' is in a faulty state, and a target H is detected in auxiliary area 10B'. Therefore, a compensation illuminance calculation step M2 can be performed for auxiliary area 10B', and a luminous output value adjustment step M3 can be performed for the adjacent sub-areas 10A and 10C, so that the light sources 400 in sub-areas 10A and 10C provide compensation illumination to auxiliary area 10B'. If the light source 400 in auxiliary area 10B' becomes usable (e.g., after repair or replacement), then auxiliary area 10B' will be converted into a sub-area, and the lighting control method for the sub-area will be applied.

[0050] In one embodiment, the lighting control method of the present invention may further include a light source load balancing step. As shown in FIG14A, this step includes continuously recording the cumulative usage time of each light source. When the difference in cumulative usage time between one light source and other neighboring light sources is too large, for example, the difference is greater than or equal to a preset balancing threshold (such as 10% of the light source's factory-marked lifespan), the light source with the longer cumulative usage time is deactivated, and the lighting function is shared by other neighboring light sources. Next, it is determined whether there are other available light sources in the sub-area. If there are other available light sources, the luminous output value of the available light sources is increased so that the illuminance of this sub-area reaches the standard before the light source was deactivated. If there are no other available light sources in the sub-area, this sub-area is defined as an auxiliary area, and the lighting compensation is provided by neighboring sub-areas. By setting it up in this way, the load of neighboring light sources can be balanced, avoiding the overuse of some light sources and increasing the probability of failure.

[0051] On the other hand, the lighting control method of the present invention may further include a light source load warning step. As shown in FIG14B, this step includes continuously recording the cumulative usage time of each light source. When the cumulative usage time is greater than or equal to a preset cumulative usage time threshold (such as 90% of the rated life of the light source), a prompt message is sent to the central control system to remind the maintenance personnel that the light source is ready for replacement. Similarly, when a light source fails, a prompt message can also be sent to the central control system to inform the maintenance personnel that the light source needs to be replaced.

[0052] Furthermore, the lighting control method of the present invention may further include a light source performance warning step. As shown in FIG14C, this step includes recording the luminous output value of each light source and the current illuminance of its respective sub-area. If the current illuminance is less than a preset illuminance reference value, a prompt message is sent to the central control system to remind the maintainer that the light source is performing poorly and needs to be repaired or replaced. The illuminance reference value can be set for different luminous output values. In one embodiment, when the luminous output value is 80% or higher, the illuminance reference value can be set to 70% of the initial illuminance of the light source, but this is not a limitation. In addition, for a sub-area with multiple light sources, the initial illuminance of the entire sub-area can be considered to set the illuminance reference value. With this setting, the hardware status of the light source can be automatically detected, and a warning can be issued before the light source completely fails, so that the maintainer can replace the light source in advance.

[0053] In one embodiment, the lighting control method of the present invention further includes a dimming rate control step. In this step, a dimming rate range is set, and the rate of change of the luminous output value of each light source is controlled to fall within the dimming rate range. For example, the dimming rate range can be set to -15% to +15% per second, that is, the new luminous output value must be between 85% and 115% of the luminous output value of the previous second. By setting it this way, the illuminance can be prevented from changing too quickly, and the flickering of the light source can be reduced, thereby improving the visual comfort of the user. When the change in the luminous output value of the light source is large, the time required to adjust the luminous output value is also longer. If the new luminous output value has been calculated while adjusting the luminous output value, the brightness of the light source can be directly adjusted based on the new luminous output value.

[0054] The lighting control method of the present invention can also adjust the lighting according to the movement state of the target. As shown in FIG15, when the target H moves, its movement direction D can be analyzed, and the predetermined illuminance of at least one sub-area in front of the target H in the movement direction D can be increased. For example, if the target is located in sub-area 10A and moves along the movement direction D (e.g., to the right), the predetermined illuminance of the sub-area 10A can be set as the working illuminance, and the right sub-area 10B can be set to have the same working illuminance to pre-illuminate the area that the target H is about to step into. Furthermore, the sub-area 10C, which is farther to the right, can have a lower predetermined illuminance, and the predetermined illuminance increases over time to form a guide path. With this setting, a certain range of lighting can be maintained in front of the user while walking, thereby improving convenience and safety.

[0055] In the embodiment shown in Figure 16, a preset movement path P can be input into the system to instruct the system to schedule lighting. The preset movement path P can be, for example, a patrol path or a maintenance path, and the arrival time of each sub-area can be predetermined. After setting the preset movement path P, the predetermined illuminance of each sub-area associated with the preset movement path P can be increased sequentially along the preset movement path P. For example, at the time point shown in the left figure of Figure 16, the user's preset position PH is within sub-area 10A. At this time, the lighting of sub-area 10A and the surrounding sub-areas can be turned on, and the lighting of the sub-area that the user will enter at subsequent time points (such as sub-area 10C) can be increased along the preset movement path P. The right figure corresponds to the illuminance distribution at the next time point. At this time, the user's preset position PH moves to sub-area 10B, and the lighting range extends upward to sub-area 10D. Different continuous lighting times can be set for different needs. For example, the lighting of sub-areas passed through on the patrol path can be turned off after a period of time, while the lighting of sub-areas passed through on the maintenance path can be maintained until the maintenance work is completed, but this is not a limitation. This setting can save energy consumption in the default mobile mode and provide route suggestions.

[0056] On the other hand, the lighting control method of the present invention also includes a lighting scheme corresponding to a static mode. Considering that users may need higher illuminance when working in a fixed position, the duration for which the number of targets in a sub-area is greater than or equal to a threshold value can be recorded. When the duration exceeds a preset dwell time threshold (e.g., but not limited to 15 seconds), the predetermined illuminance of this sub-area is increased. By setting this up, different usage states of short-term passing and long-term dwelling can be distinguished, so as to achieve the effects of precise lighting and energy saving.

[0057] The numerical limits in the foregoing embodiments can be adjusted according to the lighting field and purpose, and the same term mentioned in different steps can refer to the same or different values. For example, the threshold values ​​of the target quantity used in step S3 and step S5 can be set to be the same or different.

[0058] In summary, the present invention provides a lighting control method and a lighting control system for executing the lighting control method, providing zoned lighting in accordance with the target distribution and current illuminance in the lighting field. Through image analysis, high spatial resolution area data can be obtained, and combined with neighboring area analysis to provide gradient lighting, thereby improving the user's visual comfort.

[0059] The foregoing description is merely some preferred embodiments of the present invention. It should be noted that various changes and modifications can be made to the present invention without departing from the spirit and principles thereof. Those skilled in the art should understand that the present invention is defined by the appended claims, and that various possible substitutions, combinations, modifications, and uses, etc., do not exceed the scope of the present invention as defined by the appended claims, provided they conform to the intent of the present invention. [Simplified Explanation of the Diagram]

[0010] Figure 1 is a simplified flowchart of a lighting control method in one embodiment.

[0011] Figure 2 is a schematic diagram of a lighting control system for performing the lighting control method in the embodiment shown in Figure 1.

[0012] Figure 3 is a schematic diagram of the lighting field in the embodiment shown in Figure 1.

[0013] Figure 4 is a schematic diagram of the lighting field and the overlapping multiple partition images in another embodiment.

[0014] Figure 5 is a flowchart of the predetermined illuminance calculation steps in the embodiment shown in Figure 1.

[0015] Figure 6 is a schematic diagram of the illumination of a portion of the sub-regions in the embodiment shown in Figure 1.

[0016] Figure 7 is a flowchart of the lighting uniformity adjustment steps in one embodiment.

[0017] Figure 8 is a schematic diagram of the illumination change of the associated set in the embodiment shown in Figure 7.

[0018] Figure 9 is a flowchart of the illuminance adjustment rate setting steps in the embodiment shown in Figure 7.

[0019] Figure 10 is a flowchart of the predetermined illuminance adjustment steps in the embodiment shown in Figure 7.

[0020] Figure 11 is a simplified flowchart of the lighting compensation steps in the ancillary area.

[0021] Figure 12 is a flowchart of the compensation illuminance calculation steps in the embodiment shown in Figure 11.

[0022] Figure 13 is a schematic diagram of the lighting field in the embodiment shown in Figure 11.

[0023] Figures 14A, 14B and 14C are flowcharts of the light source load balancing step, the light source load warning step and the light source performance warning step in one embodiment, respectively.

[0024] Figure 15 is a schematic diagram of the lighting field and the moving target in another embodiment.

[0025] Figure 16 is a schematic diagram of the lighting field and the preset movement path in another embodiment.

Claims

1. A lighting control method applied to a lighting field, wherein the lighting field comprises a plurality of sub-regions, and each sub-region comprises at least one light source, the lighting control method comprising: receiving an image of the lighting field; analyzing, based on the image, a number of targets and a current illuminance in each sub-region; for each sub-region, calculating a predetermined illuminance based on the number of targets in the sub-region, the number of targets in another adjacent sub-region, and a distance of the sub-region relative to another adjacent sub-region; and for each sub-region, calculating a luminous output value of the light source in the sub-region based on the difference between the predetermined illuminance and the current illuminance.

2. The lighting control method as described in claim 1, wherein the predetermined illuminance calculation step includes: When the number of targets in the sub-area is greater than or equal to a threshold value, the predetermined illuminance is set as a working illuminance; or when the number of targets in the sub-area is less than a threshold value, the predetermined illuminance is calculated based on the number of targets in another neighboring sub-area and the distance.

3. The lighting control method as described in claim 1, further comprising: For a sub-region where the number of targets is greater than or equal to a threshold value, an association set is defined, which includes the sub-region and at least one other neighboring sub-region. An illumination uniformity is calculated based on the current illuminance of each sub-region in the association set. For each sub-region in the association set, an illuminance adjustment rate is calculated based on the illumination uniformity and the current illuminance. The predetermined illuminance is adjusted based on the illuminance adjustment rate.

4. The lighting control method as claimed in claim 3, wherein the lighting uniformity includes a first lighting uniformity, the first lighting uniformity being the ratio of the minimum to the average current illuminance of the complex sub-regions in the associated set.

5. The lighting control method as claimed in claim 3, wherein the lighting uniformity includes a second lighting uniformity, the second lighting uniformity being the ratio of the minimum to the maximum current illuminance of the complex sub-regions in the associated set.

6. The lighting control method as described in claim 3, wherein the illuminance adjustment rate setting step includes: When the lighting uniformity is less than a lighting uniformity threshold, the illuminance adjustment rate is less than 1 for the sub-area with the highest current illuminance in the associated set; and the illuminance adjustment rate is greater than 1 for the sub-area with the lowest current illuminance in the associated set.

7. The lighting control method as claimed in claim 3, wherein the predetermined illuminance adjustment step further comprises: defining a working illuminance threshold based on the lighting field; and for the sub-area where the number of targets is greater than or equal to the threshold, setting the predetermined illuminance to the greater of the working illuminance threshold and the product of the predetermined illuminance and the illuminance adjustment rate.

8. The lighting control method as claimed in claim 3, wherein the predetermined illuminance adjustment step further comprises: defining a background illuminance threshold based on the lighting field; and for the sub-area where the number of targets is less than the threshold, setting the predetermined illuminance to the larger of the background illuminance threshold and the product of the predetermined illuminance and the illuminance adjustment rate.

9. The lighting control method as claimed in claim 1, wherein the lighting area further includes at least one ancillary area, and the lighting control method further includes: Based on the image analysis, a number of targets in the ancillary area and a current illuminance are used to calculate a compensation illuminance; And adjust the luminous output value of the sub-region adjacent to the subordinate region according to the compensated illuminance.

10. The lighting control method as described in claim 9, wherein the compensated illuminance calculation step further comprises: defining the sub-area as the auxiliary area when all the light sources in the sub-area are in a deactivated state.

11. The lighting control method as claimed in claim 1 further comprises: recording the cumulative usage time of each of the light sources; and calculating the difference between the cumulative usage time of the light source and the cumulative usage time of another adjacent light source, wherein when the difference in the cumulative usage time is greater than or equal to a balance threshold, the light source is deactivated.

12. The lighting control method as described in claim 1 further includes: recording the cumulative usage time of each of the light sources; and setting a cumulative usage time threshold, and sending a prompt message when the cumulative usage time of the light source is greater than or equal to the cumulative usage time threshold.

13. The lighting control method as described in claim 1 further includes: recording the light emission output value of each light source and the current illuminance of the sub-area where it is located; setting an illuminance reference value corresponding to the light emission output value; and sending a prompt message when the current illuminance of the sub-area where the light source is located is lower than the illuminance reference value.

14. The lighting control method as described in claim 1 further includes: setting a dimming rate range, wherein the rate of change of the luminous output value of each light source falls within the dimming rate range.

15. The lighting control method as described in claim 14, wherein the dimming rate range setting step comprises: setting the dimming rate range to -15% to +15% per second.

16. The lighting control method as claimed in claim 1, further comprising: analyzing the movement direction of a target and increasing the predetermined illuminance relative to at least one sub-area in front of the target in the movement direction.

17. The lighting control method as described in claim 1 further comprises: setting a preset movement path and sequentially increasing the predetermined illuminance of each of the sub-areas associated with the preset movement path along the preset movement path.

18. The lighting control method as claimed in claim 1, further comprising: recording the duration for which the number of targets in the sub-area is greater than or equal to a threshold value, and increasing the predetermined illuminance of the sub-area when the duration is greater than a dwell time threshold value.

19. The lighting control method of claim 1, wherein the image comprises a plurality of partitioned images that overlap at least partially, wherein the lighting control method further comprises: for a sub-region corresponding to the overlapping portion of the plurality of partitioned images, calculating the number of targets in the partition and the current illuminance of the partition based on each partitioned image; and setting the number of targets to the largest among the plurality of the number of targets in the partition and the current illuminance to the smallest among the plurality of the current illuminance of the partition.

20. A lighting control system comprising: an analysis module for executing the lighting control method as described in any one of claims 1 to 19 and issuing an operation message including the luminous output value; an optical sensor signal-connected to the analysis module and for acquiring the image of the lighting field and transmitting it to the analysis module; a plurality of light sources disposed in the lighting field; and a control module signal-connected to the analysis module and the light sources and for receiving the operation message and controlling each of the light sources to adjust its brightness according to the corresponding luminous output value.

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