Lighting fixture and design method

Abstract

To achieve suppression of uncomfortable glare more easily.SOLUTION: A lighting fixture A1 includes a light source unit 1. The light source unit 1 radiates illumination light Op1. The illumination light Op1 is set in such a manner that fixture efficiency is larger than 60%, and luminous intensity satisfies at least one out of a first condition, a second condition and a third condition. In the first condition, the luminous intensity is equal to or less than a specified value of 1600[cd / 1000lm] in a viewpoint of upward 8 degrees with respect to an optical axis C1 of the lighting fixture A1. In the second condition, the luminous intensity is equal to or less than a specified value of 600[cd / 1000lm] in a viewpoint of upward 10 degrees with respect to the optical axis C1. In the third condition, the luminous intensity is equal to or less than a specified value of 200[cd / 1000lm] in a viewpoint of upward 12 degrees with respect to the optical axis C1.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to a lighting fixture and a design method thereof, and more particularly to a lighting fixture including a light source unit and a design method thereof. [Background technology]

[0002] Conventionally, as described in JIS Z 9127:2020 (sports lighting standard), glare evaluation may be performed by determining the GR (Glare Rating) based on the discomfort glare evaluation method specified in JIS Z 9100. When installing lighting equipment in stadiums, etc., advance consideration can be given to limiting discomfort glare using the above discomfort glare evaluation method.

[0003] Also, for example, Patent Document 1 discloses a glare measurement system. This glare measurement system includes a photographing camera supported rotatably in a horizontal plane, and a processing device that calculates an equivalent light veil luminance based on an image captured by the photographing camera, and calculates a glare rating value based on the equivalent light veil luminance. The photographing camera captures images at positions rotated in a horizontal plane for each angle according to the angle of view of the ultra-wide-angle lens. The processing device synthesizes a composite image centered on the glare measurement direction from the photographed images, calculates an equivalent light veil luminance based on the composite image, and calculates a glare rating value in the glare measurement direction based on the equivalent light veil luminance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-217688 A Summary of the Invention [Problem to be solved by the invention]

[0005] For example, in facilities (stadiums, etc.) where sporting and other events are held, it may be desirable to make it easier to suppress discomfort glare.

[0006] The present disclosure has been made in consideration of the above-mentioned circumstances, and has an object to provide a lighting fixture and a design method that can more easily achieve suppression of discomfort glare. [Means for solving the problem]

[0007] A lighting device according to an embodiment of the present disclosure includes a light source unit. The light source unit emits illumination light. The illumination light has a device efficiency of more than 60% and is set so that a luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition. The first condition is that the luminous intensity value is equal to or less than a specified value of 1600 [cd / 1000 lm] at a viewpoint 8 degrees above the optical axis of the lighting device. The second condition is that the luminous intensity value is equal to or less than a specified value of 600 [cd / 1000 lm] at a viewpoint 10 degrees above the optical axis. The third condition is that the luminous intensity value is equal to or less than a specified value of 200 [cd / 1000 lm] at a viewpoint 12 degrees above the optical axis.

[0008] A design method according to one aspect of the present disclosure is a design method for a lighting fixture. The design method includes an acquisition step, a determination step, and a setting step. In the acquisition step, subjective evaluation data on discomfort glare from a subject is acquired in a disturbance environment having a lighting facility. In the determination step, relative relationship information on a relative relationship between the subjective evaluation data and an evaluation model on discomfort glare is obtained to determine a specified value. In the setting step, the lighting fixture is set so that the lighting fixture efficiency is greater than 60% and the luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition for the illumination light emitted from the light source unit of the lighting fixture. The first condition is that the luminous intensity value is 1600 [cd / 1000 lm] or less as the specified value at a viewpoint 8 degrees above the optical axis of the lighting fixture. The second condition is that the luminous intensity value is 600 [cd / 1000 lm] or less as the specified value at a viewpoint 10 degrees above the optical axis. The third condition is that the luminous intensity value is equal to or less than 200 [cd / 1000 lm] as the specified value when viewed from a viewpoint 12 degrees upward with respect to the optical axis. Effect of the Invention

[0009] The present disclosure has the advantage that it becomes easier to suppress discomfort glare. [Brief description of the drawings]

[0010] [Figure 1] Fig. 1A is a perspective view of the appearance of a lighting device according to one embodiment, and Fig. 1B is a conceptual diagram for explaining conditions related to the luminous intensity value of the lighting device. [Diagram 2] FIG. 2 is a schematic diagram showing an outline of the evaluation formula for discomfort glare. [Diagram 3] Fig. 3A is a schematic diagram showing the external appearance of the disturbance environment (baseball stadium) used in Evaluation Experiment 1 on Discomfort Glare. Fig. 3B is a schematic diagram showing the above-mentioned baseball stadium. [Figure 4] Fig. 4A is a schematic diagram showing the appearance of the disturbance environment (field) used in Evaluation Experiment 2 on Discomfort Glare, and Fig. 4B is a schematic diagram showing the above-mentioned field. [Diagram 5] FIG. 5 is an explanatory diagram for explaining luminance distribution images obtained by measurement at evaluation viewpoints A to G in the baseball stadium. [Figure 6] FIG. 6 is an explanatory diagram for explaining luminance distribution images obtained by measurement at evaluation viewpoints H to N in the baseball stadium. [Figure 7] FIG. 7 is an explanatory diagram for explaining luminance distribution images obtained by measurements at evaluation viewpoints A to E in the above-mentioned field. [Figure 8] FIG. 8 is an explanatory diagram for explaining luminance distribution images obtained by measurements at evaluation viewpoints F to J in the above field. [Figure 9] FIG. 9 is a graph showing the relative relationship between the subjective evaluation data (average value) and the evaluation model (PDGRmax). [Figure 10] FIG. 10 is a graph showing the relationship between the probability of a rating of 5 (the limit at which glare is tolerable) or less and the rating model (PDGRmax). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The following describes the lighting fixtures and design methods according to the embodiments and modifications with reference to the drawings. Note that the following embodiments and modifications are merely one of the various embodiments of the present disclosure. In addition, the following embodiments and modifications can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. In addition, the configurations of the modifications can be appropriately combined.

[0012] Each drawing described in the following embodiments is a schematic drawing, and the ratio of the size and thickness of each component does not necessarily reflect the actual dimensional ratio.

[0013] (Embodiment) (1) Overview As shown in FIG. 1A, a lighting device A1 according to one embodiment includes a light source unit 1. The light source unit 1 emits an illumination light Op1 (see FIG. 1B). The illumination light Op1 is set so that the device efficiency is greater than 60% and the luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition. The first condition is that the luminous intensity value (luminous intensity) is equal to or less than a specified value of 1600 [cd / 1000 lm (lumens)] at a viewpoint 8 degrees above the optical axis C1 (see FIG. 1B) of the lighting device A1 (the position of the human eye at the first point P1 in FIG. 1B). The second condition is that the luminous intensity value is equal to or less than a specified value of 600 [cd / 1000 lm (lumens)] at a viewpoint 10 degrees above the optical axis C1 (the position of the human eye at the second point P2 in FIG. 1B). The third condition is that the luminous intensity value is equal to or less than the specified value of 200 [cd / 1000lm (lumens)] at a viewpoint 12 degrees above the optical axis C1 (the position of the human eye at the third point P3 in FIG. 1B). The "apparatus efficiency" referred to here is the ratio of the luminous flux emitted from the light source module (LED module) of the light source unit 1 of the lighting fixture A1 that exits outside the lighting fixture A1.

[0014] According to the lighting device A1 of the above embodiment, the lighting device efficiency and the luminous intensity value are set to satisfy the above-mentioned conditions. As a result, the lighting device A1 of the above embodiment has an advantage that it is easier to suppress discomfort glare. In particular, discomfort glare can be suppressed more effectively when the line of sight is upward rather than horizontally.

[0015] The lighting fixture A1 may be applied to, for example, a facility F1 (see FIG. 1B) where an event is held. The facility F1 referred to here may be, for example, a sports field such as a baseball field, soccer field, or rugby field, or a ground of a school or public facility, and the event may be a sports-related event. In particular, the sport may be a ball game. The lighting fixture A1 may be a floodlight used to illuminate (floodlight) the facility F1.

[0016] A design method according to one aspect is a method for designing lighting device A1. The design method includes an obtaining step, a determining step, and a setting step.

[0017] In the acquisition step, subjective evaluation data on discomfort glare is acquired from subjects in a disturbance environment 5 (see Figs. 3A, 3B, 4A, and 4B) having a lighting fixture 4. The "disturbance environment 5" referred to here is not an environment with few disturbances such as a laboratory, but an actual usage environment (on-site) that includes many disturbances. As an example, the disturbance environment 5 is assumed to be a facility (stadium or ground) where an event is held, similar to the facility F1 to which the lighting fixture A1 may be applied. The event held in the disturbance environment 5 may be, for example, a ball sport, similar to the event held in the facility F1 described above. The disturbance environment 5 may be the facility F1 to which the lighting fixture A1 is scheduled to be applied in the future.

[0018] In the determination step, relative relationship information regarding the relative relationship between the subjective evaluation data and the evaluation model regarding discomfort glare is obtained to determine a specified value. In the setting step, the illumination light Op1 emitted from the light source unit 1 of the lighting device A1 is set so that the device efficiency is greater than 60% and the luminous intensity value satisfies at least one of the first condition, the second condition, and the third condition. The first condition is that the luminous intensity value is a specified value of 1600 [cd / 1000 lm] or less at a viewpoint 8 degrees above the optical axis C1 of the lighting device A1. The second condition is that the luminous intensity value is a specified value of 600 [cd / 1000 lm] or less at a viewpoint 10 degrees above the optical axis C1. The third condition is that the luminous intensity value is a specified value of 200 [cd / 1000 lm] or less at a viewpoint 12 degrees above the optical axis C1.

[0019] According to the design method of the above embodiment, the fixture efficiency and luminous intensity value are set to satisfy the above conditions. As a result, the design method of the above embodiment has an advantage that it is possible to provide a lighting fixture A1 that is more likely to suppress discomfort glare. In particular, discomfort glare can be more effectively suppressed in cases where the line of sight is upward rather than horizontally.

[0020] (2)Details The lighting fixture A1 according to this embodiment will be described in detail below with reference to Figs. 1A to 10. As described above, the lighting fixture A1 is assumed to be a floodlight used to floodlight a facility F1 where an event is held (see Figs. 1A and 1B). The facility F1 is a stadium or ground where a ball game event (e.g., baseball, soccer, rugby, tennis, basketball, etc.) is held. Here, the description focuses on one lighting fixture A1. As an actual usage example, a plurality of lighting fixtures A1 are installed on a lighting tower or the like to illuminate the stadium or ground from above.

[0021] As shown in FIG. 1A, the lighting device A1 includes a light source unit 1, an arm 2 that supports the light source unit 1, a power supply unit 3 that supplies power to the light source unit 1 for lighting, a display member D1, and a locking mechanism .

[0022] The light source unit 1 emits illumination light Op1. The light source unit 1 includes a light source module, a cover 11, a heat dissipation block 12, and the like. The light source module is, for example, an LED module in which a plurality of LEDs (Light Emitting Diodes) are mounted on the front surface of a flat substrate as a plurality of light-emitting elements. Each light-emitting element is, for example, a packaged white LED for illumination. However, the light-emitting element is not limited to an LED, and may be an organic electroluminescence element, a semiconductor laser element, or the like.

[0023] The cover 11 is disposed in front of the light source unit 1 so as to radiate the light emitted from the light source unit 1 to the outside of the lighting fixture A1 as illumination light Op1, thereby performing light distribution control. The cover 11 is integrally formed from a translucent synthetic resin such as an acrylic resin or a polycarbonate resin. The cover 11 has a plurality of lens portions. Each lens portion is disposed at a position corresponding one-to-one to a plurality of light-emitting elements in the light source module.

[0024] The heat dissipation block 12 has a base member and a plurality of plate-shaped heat dissipation members 121. The base member is formed, for example, from an aluminum alloy in a rectangular flat plate shape. A substrate of the light source module is attached to the front surface of the base member using a plurality of screws. Each of the plurality of heat dissipation members 121 is formed, for example, from an aluminum alloy. The plurality of heat dissipation members 121 are attached to the rear surface of the base member at regular intervals. The heat dissipation block 12 dissipates heat generated by the plurality of light-emitting elements during lighting, thereby suppressing a temperature rise of the light source module and improving light emission efficiency.

[0025] The power supply unit 3 includes a power supply device and a power supply case 30 that houses the power supply device. The power supply device converts AC power supplied from a commercial power source into DC power, and operates to make the current value of the DC current supplied to the light source module of the light source unit 1 match a target value (for example, a rated current value of the light source module). However, the power supply device may have a function (dimming function) to adjust the target value of the DC current supplied to the light source module to a value lower than the rated current value.

[0026] The power supply case 30 has a box-shaped case body 31 with one side (rear side) open, and a case lid 32 that closes the open side (rear side) of the case body 31. Both the case body 31 and the case lid 32 are formed of an aluminum alloy. Two power supply lines S1 and S2 are led out from the bottom surface of the power supply case 30. The two power supply lines S1 and S2 are electrically connected to the power supply device. The power supply line S1 is electrically connected to the light source unit 1, and transmits DC current output from the power supply device to the light source unit 1. The power supply line S2 is electrically connected to a commercial power source, and transmits AC power output from the commercial power source to the power supply device. The case lid 32 is formed in a rectangular flat plate shape. The case lid 32 overlaps the rear end surface of the case body 31 to cover the open surface of the case body 31, and is screwed to the case body 31 with a plurality of screws. The power supply unit 3 is fixed to the light source unit 1 by a pair of fixing bases 6 (only one of which is shown in FIG. 1A).

[0027] The arm 2 is formed by processing a metal plate. The arm 2 has a bottom 22 and a pair of support parts 21 extending upward from both the left and right ends of the bottom 22. The pair of support parts 21 are fixed to the light source unit 1 (and the power supply unit 3) via the display member D1 by bolts 23 or the like. The bottom 22 is fixed to the mounting base Z1, which is the fixed surface, by bolts 221 or the like. A scale 222 is provided on the surface of the bottom 22. The lighting device A1 can rotate around the bolt 221 as a fulcrum (rotation axis) when the bolt 221 is loosened. A mark M1 is provided on the upper end of the left support part 21 of the pair of support parts 21 so as to point to the scale D2 of the display member D1.

[0028] The display member D1 is formed into a disk shape from a metal plate. A scale D2 is provided on the display surface of the display member D1. A stopper is provided on the peripheral portion of the display member D1. The lock mechanism 26 has a handle 260 and is connected to the arm 2. The lock mechanism 26 cooperates with the stopper of the display member D1 to regulate the rotation angle of the light source unit 1 (and the display member D1 and the power supply unit 3) which is rotatable around the bolt 23 as a fulcrum (rotation axis).

[0029] A worker installing lighting fixture A1 visually checks mark M1 and scale D2, and adjusts the angle of light source unit 1 around bolt 23 as a fulcrum (axis of rotation) to set the up-down direction of optical axis C1 (see FIG. 1B) of lighting fixture A1. Also, while visually checking scale 222, the worker adjusts the angle of light source unit 1 around bolt 221 as a fulcrum (axis of rotation) to set the left-right direction of optical axis C1 (see FIG. 1B) of lighting fixture A1.

[0030] [Lighting fixture settings] In this embodiment, based on the results of an evaluation experiment described later, the illumination light Op1 emitted from the light source unit 1 is set so that the fixture efficiency is greater than 60% and the luminous intensity value satisfies at least one of the following first to third conditions. As described above, the fixture efficiency is the ratio of the luminous flux emitted from the light source module of the light source unit 1 that exits the lighting fixture A1 via the cover 11.

[0031] The first condition is that the luminous intensity value is equal to or less than the specified value of 1600 [cd / 1000lm] when viewed from 8 degrees above the optical axis C1 of the lighting fixture A1. This specified value = 1600 [cd / 1000lm] is obtained by dividing 80000 [cd] by the fixture luminous flux of 50000 [lm] and multiplying the result by 1000, to obtain a numerical value per 1000 [lm] like a general light distribution curve. Note that, as an additional condition to the first condition, it is preferable that the luminous intensity value is equal to or less than the specified value of 80000 [cd] when viewed from 8 degrees above the optical axis C1.

[0032] The second condition is that the luminous intensity value is equal to or less than the specified value of 600 [cd / 1000lm] when viewed from a viewpoint 10 degrees above the optical axis C1. This specified value = 600 [cd / 1000lm] is obtained by dividing 30000 [cd] by the fixture luminous flux of 50000 [lm] and multiplying the result by 1000, to obtain a numerical value per 1000 [lm], similar to a general light distribution curve. Note that, as an additional condition to the second condition, it is preferable that the luminous intensity value is equal to or less than the specified value of 30000 [cd] when viewed from a viewpoint 10 degrees above the optical axis C1.

[0033] The third condition is that the luminous intensity value is equal to or less than the specified value of 200 [cd / 1000lm] when viewed from 12 degrees above the optical axis C1. This specified value = 200 [cd / 1000lm] is obtained by dividing 10000 [cd] by the fixture luminous flux of 50000 [lm] and multiplying the result by 1000, to obtain a value per 1000 [lm] like a general light distribution curve. Note that, as an additional condition to the third condition, it is preferable that the luminous intensity value is equal to or less than the specified value of 10000 [cd] when viewed from 12 degrees above the optical axis C1.

[0034] The first to third conditions will be described in detail with reference to Fig. 1B. Fig. 1B is a conceptual diagram showing a state in which a lighting fixture A1 is installed on the top of a lighting tower G1 so as to floodlight a facility F1, for example. The lighting fixture A1 is placed at an installation height H1 from the ground. The installation height H1 may be, for example, 24 [m] if the facility F1 is a small to medium-sized field or ground, and may be, for example, 13 [m] if the facility F1 is a school ground.

[0035] In FIG. 1B, point P0 corresponds to the position where the optical axis C1 of lighting fixture A1 intersects with the ground. In other words, during the installation work of lighting fixture A1, the vertical orientation of lighting fixture A1 is adjusted so that the optical axis C1 coincides with point P0 at a predetermined distance from the edge of the ground. The angle φ1 between the optical axis C1 and the vertical direction of lighting fixture A1 may be about 70 degrees. The distance L1 from lighting tower G1 to point P0 depends on the size of facility F1, but for a small to medium-sized field or ground, the angle φ1 = 67 degrees and L1 = 57 [m], and for a school ground, the angle φ1 = 72 degrees and L1 = 40 [m].

[0036] The first point P1 is a position where the viewpoint of a person standing at that point is θ1 (=8 degrees) above the optical axis C1. The second point P2 is a position where the viewpoint of a person standing at that point is θ2 (=10 degrees) above the optical axis C1. The third point P3 is a position where the viewpoint of a person standing at that point is θ3 (=12 degrees) above the optical axis C1.

[0037] In other words, in the case of Fig. 1B, the first condition is that the luminous intensity value is equal to or less than a specified value of 1600 [cd / 1000lm] at the viewpoint of the first point P1, the second condition is that the luminous intensity value is equal to or less than a specified value of 600 [cd / 1000lm] at the viewpoint of the second point P2, and the third condition is that the luminous intensity value is equal to or less than a specified value of 200 [cd / 1000lm] at the viewpoint of the third point P3.

[0038] The luminous intensity value is preferably set so as to satisfy all of the first to third conditions, but may satisfy only one of them.

[0039] In this embodiment, the light output control of the light source unit 1 and the light distribution control (light distribution pattern) by the cover 11 including the lens portion and the like are set so that the fixture efficiency and luminous intensity value satisfy the above conditions.

[0040] [Evaluation experiments and evaluation models] The inventors of the present disclosure conducted the evaluation experiments described below, and as a result of thorough verification, derived the "prescribed values" of the first to third conditions related to the above-mentioned luminous intensity values ​​using an evaluation model related to discomfort glare.

[0041] First, the evaluation formula on which the above-mentioned evaluation model for discomfort glare is based will be explained with reference to Fig. 2. The evaluation formula for DGR (Direct Glare Rating) shown in Fig. 2 is based on the four major elements of glare.

[0042] As shown in Figure 2(a), the higher the "luminance of the light source," the more likely people are to perceive the light source as dazzling. In other words, the higher the value of the light source luminance La, the more likely people are to perceive discomfort glare.

[0043] As shown in Figure 2(b), the larger the "light source solid angle (apparent size of the light source)," the more likely people are to perceive the light source as dazzling. In other words, the larger the light source solid angle ω, the more likely people are to perceive discomfort glare.

[0044] As shown in Figure 2(c), the darker the surroundings are and the more accustomed our eyes are to the dark, the more likely we are to perceive the light source as dazzling. The higher the background luminance Lb, the less likely we are to perceive discomfort glare. Also, the higher the adaptation luminance Lve, the less likely we are to perceive discomfort glare.

[0045] As shown in (d) of Figure 2, the closer a light source is to the line of sight, the more likely a person is to perceive the light source as dazzling. In other words, the greater the separation angle ε between the line of sight and the light source (optical axis), the less likely a person is to perceive discomfort glare.

[0046] In FIG. 2, the light source luminance La, the light source solid angle ω, the adaptation luminance Lve, the background luminance Lb, and the separation angle ε are set as independent variables, and the relationship between them is shown as a function, which is the evaluation formula DGR.

[0047] In the case of the present embodiment where the event is a ball sport, players may lose sight of a visual object such as a ball due to the occurrence of discomfort glare. Using this evaluation formula DGR, it is possible to calculate the DGR value, and when the DGR value exceeds a certain threshold, it is possible to determine that discomfort glare is present. However, since this formula can be said to be a formula established through laboratory experiments, it is necessary to consider the field factor at the site.

[0048] Therefore, in this embodiment, an evaluation model P that indicates the proportion of people who experience discomfort glare is provided based on the above evaluation formula DGR. DGR The evaluation model includes a plurality of parameters. In this embodiment, the plurality of parameters include the above-mentioned luminance of the light source, the light source solid angle indicating the apparent size of the light source, the background luminance, the adaptation luminance, and the angle of separation between the light source and the line of sight of the person. The evaluation model is expressed by the following formula (1).

[0049]

number

[0050] The inventors of the present disclosure then conducted evaluation experiments in an actual site, i.e., in a disturbance environment 5 including a lighting facility 4, and identified a luminous intensity value to be the specified value based on the correlation between the subjective evaluation of subjects who actually subjectively perceived discomfort glare and the above formula (1).

[0051] In other words, the specified values ​​for each of the first, second, and third conditions are determined based on the relative relationship information. The relative relationship information is information on the relative relationship between the subjective evaluation data by subjects regarding discomfort glare obtained in a disturbance environment 5 and the evaluation model regarding discomfort glare: the above formula (1).

[0052] The disturbance environment 5 is an environment in which an event will be held. As described above, the disturbance environment 5 is assumed to be a facility (stadium or ground) similar to the facility F1 to which the lighting device A1 may be applied. In other words, the event held in the disturbance environment 5 may be, for example, a sport (particularly a ball sport) similar to the event held in the facility F1. The disturbance environment 5 may also be the facility F1 to which the lighting device A1 will be applied in the future (or will be applied in the future).

[0053] The subjective evaluation data includes a plurality of subjective evaluation results obtained respectively from a plurality of evaluation viewpoints in the disturbance environment 5 (evaluation viewpoints A to N in a baseball stadium 5A and evaluation viewpoints A to J in a field 5B, which will be described later).

[0054] In order to obtain subjective evaluation data, the inventors of the present disclosure conducted evaluation experiments in a plurality of disturbance environments 5 having different design illuminances. In other words, the subjective evaluation data in this embodiment includes data obtained in a plurality of disturbance environments 5 having different design illuminances.

[0055] The evaluation experiments (Evaluation Experiment 1, Evaluation Experiment 2) carried out in a plurality of disturbance environments 5 (on-site) to obtain subjective evaluation data will be described in detail below.

[0056] [Evaluation experiment 1] In evaluation experiment 1, a baseball stadium 5A shown in Fig. 3A and Fig. 3B was selected as the disturbance environment 5. The baseball stadium 5A is a park baseball stadium, and has lighting equipment 4 installed on each of four lighting towers. The design illuminance of the infield is set to 500lx, and the design illuminance of the outfield is set to 300lx.

[0057] The date and time of evaluation experiment 1 is from 16:00 to 20:00 on Monday, January 31, 2022. At this time of the year, the surroundings would be a relatively dark environment without lighting. There were 17 subjects in total (14 men and 3 women) in the age range of their 20s to 50s. The lighting equipment 4 includes multiple lighting fixtures 40. Each lighting fixture 40 is an LED floodlight with a medium-angle light distribution. The lighting fixtures 40 are installed at a height of 23.2 m.

[0058] In the experiment, evaluation viewpoints A through N where subjects stood were set in a distributed manner within the infield and outfield of stadium 5A, as shown in Fig. 3B. The subjects were asked to direct their gaze in the direction indicated on the display device at each of evaluation viewpoints A through N (as if looking almost directly at lighting fixture 40) and evaluate the perceived glare (brightness) using the evaluation items (subjective evaluation value on a 9-point scale).

[0059] In evaluation experiment 1, the gaze direction from each evaluation viewpoint was set to the lighting fixture 4 (the lighting fixture 4X on the left side) on the same lighting tower, as shown by the arrow in Figure 3B. In other words, in evaluation experiment 1, the lighting fixture 4 to be gazed was fixed to the left lighting fixture 4X among the four lighting fixtures 4 at each evaluation viewpoint.

[0060] The evaluation items (subjective evaluation values ​​on a nine-point scale) are "Rating 1" to "Rating 9," as shown on the vertical axis of Fig. 9. The ratings start with "Rating 1: Not bothersome," followed by "Rating 3: Not bothersome at all," "Rating 5: Limit of acceptability," "Rating 7: Obstructive," and "Rating 9: Unbearable." In other words, the subjects were asked to give a higher rating the more dazzling the light they felt.

[0061] [Evaluation experiment 2] In evaluation experiment 2, a football / soccer field 5B shown in Fig. 4A and Fig. 4B was selected as the disturbance environment 5. The field 5B is a ground within the premises of a factory, and has lighting equipment 4 installed on each of eight lighting towers. The design illuminance of the field 5B is set to 100 lx.

[0062] The date and time of evaluation experiment 2 is from 17:00 to 19:30 on Tuesday, March 29, 2022. At this time of the year, the surroundings would be a relatively dark environment without lighting. There were a total of seven subjects (six men and one woman) in their 30s to 50s. The lighting equipment 4 includes multiple lighting fixtures 40. Each lighting fixture 40 is a 600 W, 63,600 lumens (lm) LED floodlight. The lighting fixtures 40 are installed at a height of 14.5 m.

[0063] As shown in FIG. 4B, the experiment included dispersively setting evaluation viewpoints A to J within the field 5B. The arrows in FIG. 4B indicate the gaze direction specified at the position (viewpoint) where the subject stands. The arrows D, I, and J indicate three different gaze directions from the same white circle position (viewpoint), and the arrows C, G, and H indicate three different gaze directions from the same white circle position (viewpoint). However, for convenience of explanation, these arrows D, I, J, C, G, and H will also be referred to as "evaluation viewpoints". Each gaze direction (arrow) of the evaluation viewpoints A to J points to the lighting equipment 4 toward which the gaze is directed. In other words, in evaluation experiment 2, unlike evaluation experiment 1, the lighting equipment 4 toward which the gaze is directed is not fixed to one.

[0064] The subjects were asked to direct their gaze in the designated direction at each of the evaluation viewpoints A to J (as if looking directly at the lighting fixture 40) and evaluate the perceived glare using the evaluation items (9-point scale). The evaluation items (9-point scale) were the same as those in Evaluation Experiment 1.

[0065] [Measurements from each evaluation perspective] In the above evaluation experiments 1 and 2, not only were subjects given subjective evaluations, but also measurement devices were used to measure various items at each evaluation viewpoint (evaluation viewpoints A-N at the baseball stadium 5A, and evaluation viewpoints A-J at the field 5B). The measured items and the measurement devices used for the measurements are shown in Table 1 below. The reflectance, which is a measurement item in Table 1, is the reflectance of the ground with respect to the light from the lighting fixture 40, and is used in conjunction with the illuminance to determine the adaptation luminance. The light source solid angle and separation angle were calculated from the design data of the lighting fixture 40, rather than being measured.

[0066] [Table 1]

[0067] The measured values ​​of the above measurement items and the calculated values ​​of the light source solid angle and separation angle are substituted into the above formula (1) to obtain the P of each lighting fixture 40. DGR This P DGR The calculated value is used in the "second step" described below.

[0068] 5 and 6 show various images obtained when measuring the above measurement items in the evaluation experiment 1 at the baseball stadium 5A. "A" to "N" in FIG. 5 and FIG. 6 correspond to the evaluation viewpoints A to N of the baseball stadium 5A. FIG. 5 and FIG. 6 show "luminance distribution images: monochrome and color distribution" of the light irradiated from the lighting equipment 4 including the multiple lighting fixtures 40 in the line of sight direction specified at each of the evaluation viewpoints A to N. Note that the color distribution images in FIG. 5 and FIG. 6 are shown in grayscale for convenience of drawing. Comparing the luminance distribution images in FIG. 5 and FIG. 6, it can be seen that the glare is relatively large at the evaluation viewpoints A, D, E, and J to L compared to the other evaluation viewpoints.

[0069] 7 and 8 show various images obtained when measuring the above measurement items in evaluation experiment 2 in field 5B. "A" to "J" in Fig. 7 and Fig. 8 correspond to evaluation viewpoints A to J in field 5B. Fig. 7 and Fig. 8 show "luminance distribution images: monochrome and color distribution" of light irradiated from a lighting facility 4 including multiple lighting fixtures 40 in the line of sight direction specified at each evaluation viewpoint A to J. Note that the color distribution images in Fig. 7 and Fig. 8 are shown in grayscale for convenience of illustration. Comparing the luminance distribution images in Fig. 7 and Fig. 8, it can be seen that the evaluation viewpoints A, D, E, I, and J have relatively large glare compared to the other evaluation viewpoints.

[0070] [Relationship between subjective evaluation data and evaluation model] As described above, the relative relationship information on which the specified values ​​of the first to third conditions are determined is information on the relative relationship between the subjective evaluation data obtained in the above evaluation experiment and the evaluation model. Here, the specified values ​​are determined based on the following first to third procedures.

[0071] In the first step, for each evaluation viewpoint, values ​​corresponding to the multiple parameters measured in the disturbance environment 5 for each of the multiple lighting devices 40 are substituted into the above formula (1) to obtain P DGR Specifically, the measured values ​​at each of the evaluation viewpoints A to N of the stadium 5A and the calculated values ​​of the light source solid angle and separation angle are substituted into the above formula (1) to obtain the P of each lighting fixture 40 (of the lighting equipment 4X at the line of sight). DGRSimilarly, the measured values ​​at each of the evaluation viewpoints A to J in the field 5B and the calculated values ​​of the light source solid angle and separation angle are substituted into the above formula (1) to obtain the P of each lighting fixture 40 (of the lighting equipment 4 at the line of sight). DGR Request.

[0072] In the second step, multiple P DGR Among them, P which shows the maximum value DGR In the following, the maximum value is defined as "PDGR max Specifically, for each of the evaluation viewpoints A to N of the stadium 5A, the P of the plurality of lighting fixtures 40 (of the lighting equipment 4X at the line of sight) is DGR Of these, PDGR max Similarly, for each of the evaluation viewpoints A to J in the field 5B, P of the plurality of lighting fixtures 40 (of the lighting equipment 4 at the line of sight) is specified. DGR Of these, PDGR max In other words, the number of PDGRs is the same as the number of evaluation perspectives. max is identified.

[0073] In the third step, P DGR From the results of the multiple subjective evaluations, a luminous intensity value that is the limit at which discomfort glare can be tolerated is identified. Here, reference is made to the graph shown in FIG. 9. In FIG. 9, the horizontal axis (X axis) is the PDGR max The vertical axis (Y axis) represents the subjective evaluation value on a nine-point scale. max A graph with is shown.

[0074] The numerous plots PL1 in Fig. 9 show the PDGRs at each actual evaluation viewpoint. max The plot is based on the average of the nine-point subjective evaluation values ​​obtained from multiple subjects at the evaluation viewpoint. For example, taking evaluation viewpoint A of stadium 5A as an example, the average of 17 subjective evaluation values ​​obtained from 17 subjects for evaluation viewpoint A was calculated. Then, PDGR at the evaluation viewpoint A was calculated. maxPlots PL1 with the above as the X-axis value and the calculated average as the Y-axis value are included in many plots PL1 in Fig. 9. In fact, evaluation experiments were also conducted in another disturbance environment 5 (site: a professional baseball stadium with a design illuminance of 2000lx for the infield and 1500lx for the outfield) in addition to the stadium 5A and field 5B, and the number of plots PL1 shown is the same as the number of evaluation viewpoints at these three sites.

[0075] From the numerous plots PL1 shown in Fig. 9, it was shown that there is a high correlation between the subjective evaluation data (average value of the subjective evaluation value) and the evaluation model (see the proportional line Q1). Information on the plots PL1 and the proportional line Q1 shown in Fig. 9 can be said to be part of the relative relationship information.

[0076] Next, let us refer to the graph shown in FIG. 10. In FIG. 10, the horizontal axis (X axis) is PDGR max The vertical axis (Y axis) represents the probability [%] that the subjective evaluation value is below "Rating 5: Acceptable limit". In other words, Figure 10 shows the PDGR max A graph with is shown.

[0077] The plots PL2 in Fig. 10 are similar to those in Fig. 9, and show the PDGRs at each evaluation viewpoint in the three sites. max The plot is based on the probability of a subjective evaluation score of 5 or less on a nine-point scale obtained from multiple subjects at the evaluation viewpoint. For example, let's take evaluation viewpoint A of stadium 5A as an example. If all 17 subjective evaluation scores obtained from 17 subjects at evaluation viewpoint A are 5 or less, the probability is set to 100%. Then, max A plot PL2 with x = 0 [%] as the X-axis value and 100[%] as the Y-axis value is included among the many plots PL2 in FIG.

[0078] A curve R1 in Fig. 10 indicates a cumulative distribution curve. Also shown in Fig. 10 are a first defined line T1 indicating a position of a probability of 50% and a second defined line T2 indicating a position of a probability of 75%. Information regarding the plot PL2, the cumulative distribution curve, the first defined line T1, and the second defined line T2 shown in Fig. 10 can be said to be part of relative relationship information.

[0079] In this embodiment, when determining the prescribed value, a first prescribed line T1 indicating 50% is used, and the PDGR at the intersection X1 where the first prescribed line T1 and the curve R1 (cumulative distribution curve) intersect is max = 117 is applied. However, the second prescribed line T2 indicating 75% is adopted, and the PDGR at the intersection X2 where the second prescribed line T2 and the curve R1 intersect is max =94.1 may be applied.

[0080] Next, P.D.G.R. max = 117 (or 94.1) and the values ​​of the parameters other than the light source luminance are substituted into the above formula (1) to obtain the light source luminance L a , i.e., the luminance regulation value [cd / m 2 ] is then calculated backwards, and the specified value [cd / 1000lm] of the luminous intensity value for conditions 1 to 3 is calculated from the backward-calculated luminance regulation value. The numerical values ​​of parameters other than the light source luminance mentioned here (i.e., light source solid angle, background luminance, adaptation luminance, and separation angle) can be found from the design data (apparatus data) of the lighting fixture A1 itself and the design data of the construction surface on which the fixture is installed (lighting design data: installation height, design illuminance, irradiation angle). For example, if it is assumed that facility F1 is a school grounds, the adaptation luminance to be substituted into formula (1) is found with a design illuminance of 100lx and a reflectance of 0.1. If facility F1 is an (outdoor) school grounds, the background luminance may be, for example, 0.2 [cd / m 2 ]. The above fixture data may include the light-emitting area, the inclination of the optical axis C1 from the center of the fixture, etc. (or the apparent light-emitting area as viewed from the optical axis C1). The above lighting design data may also include the angle of the irradiation direction of the optical axis C1, the vertical angle of the floodlight, etc. The light source solid angle may be calculated from the above fixture data and lighting design data.

[0081] Based on the specified luminous intensity value obtained by back-calculation for the assumed facility F1, the inventors of the present disclosure derived the first to third conditions that are optimal as the specified values ​​for each viewpoint 8 degrees, 10 degrees, and 12 degrees above the optical axis C1, taking into account the case where the line of sight is above the horizontal direction. Regarding the other condition, "the fixture efficiency is greater than 60%," if the fixture efficiency is set low, for example to 60% or less, glare can be easily suppressed, but sufficient floodlighting may not be provided. In contrast, with the lighting fixture A1, by satisfying at least one of the first to third conditions while providing sufficient floodlighting by setting the fixture efficiency to greater than 60%, it becomes easier to suppress discomfort glare.

[0082] (Modification) Modifications of the above embodiment are listed below. The modifications described below can be applied in appropriate combination.

[0083] The lighting device A1 of the above embodiment, which is more likely to suppress discomfort glare, can also be provided by applying the following design method. That is, the design method includes an acquisition step, a determination step, and a setting step. In the acquisition step, subjective evaluation data of a subject is acquired in a disturbance environment 5. In the determination step, relative relationship information regarding the relative relationship between the subjective evaluation data and an evaluation model related to discomfort glare is obtained to determine a prescribed value. In the setting step, illumination light Op1 emitted from light source unit 1 of lighting device A1 is set so that the device efficiency is greater than 60% and the luminous intensity value satisfies at least one of the first to third conditions described above.

[0084] In the above embodiment, the event is assumed to be a ball sport. However, the event may be an event related to a sport other than a ball game (for example, track and field events, etc.). The event is not limited to an event related to a sport, and the facility F1 may be a theme park, a live music venue, etc. The facility F1 to which the lighting fixture A1 is applied is not limited to an outdoor facility, and may be an indoor facility, for example, a dome stadium, or a gymnasium in a school or public facility. The facility F1 may also be a facility where no event is held (a road, a park, a building, a garden, etc.).

[0085] (summary) The above-described embodiments and the like disclose the following aspects.

[0086] A lighting fixture (A1) according to a first embodiment includes a light source unit (1). The light source unit (1) emits illumination light (Op1). The illumination light (Op1) is set so that the fixture efficiency is greater than 60% and the luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition. The first condition is that the luminous intensity value is equal to or less than a specified value of 1600 [cd / 1000 lm] at a viewpoint 8 degrees above the optical axis (C1) of the lighting fixture (A1). The second condition is that the luminous intensity value is equal to or less than a specified value of 600 [cd / 1000 lm] at a viewpoint 10 degrees above the optical axis (C1). The third condition is that the luminous intensity value is equal to or less than a specified value of 200 [cd / 1000 lm] at a viewpoint 12 degrees above the optical axis (C1).

[0087] According to the above aspect, the fixture efficiency and luminous intensity value are set to satisfy the above conditions. As a result, the luminaire (A1) has the advantage that it is easier to achieve suppression of discomfort glare.

[0088] With respect to the lighting fixture (A1) according to the second aspect, in the first aspect, the first condition is an additional condition that the luminous intensity value is equal to or less than a specified value of 80,000 [cd] when viewed from an angle of 8 degrees above the optical axis (C1). The second condition is an additional condition that the luminous intensity value is equal to or less than a specified value of 30,000 [cd] when viewed from an angle of 10 degrees above the optical axis (C1). The third condition is an additional condition that the luminous intensity value is equal to or less than a specified value of 10,000 [cd] when viewed from an angle of 12 degrees above the optical axis (C1).

[0089] According to the above aspect, the accuracy of the above first to third conditions is improved, and as a result, discomfort glare is further suppressed.

[0090] In the first or second aspect of the lighting fixture (A1) according to the third aspect, the specified values ​​for each of the first, second and third conditions are determined based on relative relationship information. The relative relationship information is information on the relative relationship between subjective evaluation data by subjects on discomfort glare obtained in a disturbance environment (5) having a lighting installation (4) and an evaluation model on discomfort glare.

[0091] According to the above aspect, the accuracy of the above first to third conditions is improved, and as a result, discomfort glare is further suppressed.

[0092] In the third aspect of the present invention, the evaluation model for the lighting device (A1) according to the fourth aspect includes a plurality of parameters, including the luminance of the light source, a light source solid angle indicating the apparent size of the light source, background luminance, adaptation luminance, and a separation angle between the light source and the line of sight of a person.

[0093] According to the above aspect, the accuracy of the above first to third conditions is improved, and as a result, discomfort glare is further suppressed.

[0094] Regarding the lighting fixture (A1) according to the fifth aspect, in the fourth aspect, the evaluation model is expressed by the following formula (1).

[0095]

number

[0096] According to the above aspect, the accuracy of the above first to third conditions is improved, and as a result, discomfort glare is further suppressed.

[0097] In the fifth aspect, the lighting installation (4) includes a plurality of lighting devices (40) in relation to the lighting device (A1) according to the sixth aspect. The subjective evaluation data includes a plurality of subjective evaluation results obtained at a plurality of evaluation viewpoints (evaluation viewpoints A to N in a stadium 5A and evaluation viewpoints A to J in a field 5B) in a disturbance environment (5). For each evaluation viewpoint, values ​​corresponding to a plurality of parameters measured in the disturbance environment (5) for each of the plurality of lighting devices (40) are substituted into equation (1) to obtain P DGR Calculate multiple P for multiple lighting fixtures (40). DGR Among them, P which shows the maximum value DGR and P, which shows multiple maximum values ​​identified from multiple evaluation viewpoints. DGR The specified value is determined by identifying the luminous intensity value that is the limit of tolerance for discomfort glare from the results of the multiple subjective evaluations.

[0098] According to the above aspect, the accuracy of the above first to third conditions is improved, and as a result, discomfort glare is further suppressed.

[0099] Regarding the lighting device (A1) according to the seventh aspect, in any one of the third to sixth aspects, the subjective assessment data includes data obtained in a plurality of disturbance environments (5) having mutually different design illuminances.

[0100] According to the above aspect, since more abundant data can be easily obtained, the accuracy regarding the above first to third conditions is improved, and as a result, discomfort glare is further suppressed.

[0101] A lighting fixture (A1) according to an eighth aspect is a lighting fixture applied to a facility (F1) where an event is held in any one of the first to seventh aspects. The facility (F1) is a sports field or a ground where a ball game event is held.

[0102] According to the above aspect, when the lighting device (A1) is applied to light a stadium or ground, the possibility that participants in an event (e.g., players) experience discomfort glare when they move their eyes to the ball is reduced.

[0103] A design method according to a ninth aspect is a design method for a lighting fixture (A1). The design method includes an acquisition step, a determination step, and a setting step. In the acquisition step, subjective evaluation data on discomfort glare from a subject is acquired in a disturbance environment (5) having a lighting facility (4). In the determination step, relative relationship information on the relative relationship between the subjective evaluation data and an evaluation model on discomfort glare is obtained to determine a specified value. In the setting step, illumination light (Op1) emitted from a light source unit (1) of the lighting fixture (A1) is set so that the fixture efficiency is greater than 60% and the luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition. The first condition is that the luminous intensity value is a specified value of 1600 [cd / 1000 lm] or less at a viewpoint 8 degrees above the optical axis (C1) of the lighting fixture (A1). The second condition is that the luminous intensity value is a specified value of 600 [cd / 1000 lm] or less at a viewpoint 10 degrees above the optical axis (C1). The third condition is that the luminous intensity value is a specified value of 200 [cd / 1000lm] or less when viewed from a viewpoint 12 degrees upward from the optical axis (C1).

[0104] According to the above aspect, the fixture efficiency and luminous intensity value are set to satisfy the above conditions. As a result, the design method has the advantage of being able to provide a lighting fixture (A1) that can more easily suppress discomfort glare.

[0105] The configurations according to the second to eighth aspects are not essential for the lighting fixture (A1) according to the first aspect, and may be omitted as appropriate. [Explanation of symbols]

[0106] A1 Lighting equipment 1 Light source unit 4. Lighting equipment 40 Lighting equipment 5. Disturbance environment C1 optical axis F1 Facilities Op1 Illumination light

Claims

1. A lighting fixture including a light source unit that emits illumination light, The illumination light is set so that the fixture efficiency is greater than 60% and the luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition; The first condition is that the luminous intensity value is equal to or less than a specified value of 1600 [cd / 1000lm] when viewed from a viewpoint 8 degrees above the optical axis of the lighting device, The second condition is that the luminous intensity value is equal to or less than a specified value of 600 [cd / 1000lm] at a viewpoint 10 degrees above the optical axis, The third condition is that the luminous intensity value is equal to or less than a specified value of 200 [cd / 1000lm] at a viewpoint 12 degrees above the optical axis. Lighting fixtures.

2. The first condition includes an additional condition that the luminous intensity value is equal to or less than a specified value of 80,000 [cd] at a viewpoint 8 degrees above the optical axis, The second condition includes an additional condition that the luminous intensity value is equal to or less than a specified value of 30,000 [cd] at a viewpoint 10 degrees above the optical axis, The third condition includes, as an additional condition, that the luminous intensity value is equal to or less than a specified value of 10,000 [cd] at a viewpoint 12 degrees above the optical axis.

2. A lighting fixture according to claim 1.

3. the specified value in each of the first condition, the second condition, and the third condition is determined based on relative relationship information; The relative relationship information is information on a relative relationship between subjective evaluation data by subjects regarding discomfort glare obtained in a disturbance environment having a lighting facility and an evaluation model regarding discomfort glare.

2. A lighting fixture according to claim 1.

4. The evaluation model includes a plurality of parameters; The plurality of parameters include a luminance of a light source, a light source solid angle indicating an apparent size of the light source, a background luminance, an adaptation luminance, and a separation angle between the light source and a line of sight of a person.

4. A lighting device according to claim 3.

5. The evaluation model is expressed by the following formula (1):

5. A lighting device according to claim 4. [0010] Here, L ａ : Light source luminance (cd / m ２ ), ω: Light source solid angle (sr) L ｖｅ : Adaptation luminance (cd / m ２ ) L ｂ : background luminance (cd / m ２ ) ε: Separation angle (°) P ＤＧＲ : Percentage of people who experience discomfort glare A, B, C, D, E, α, β, γ: coefficient

6. The lighting fixture includes a plurality of lighting fixtures; the subjective assessment data includes a plurality of subjective assessment results obtained at a plurality of assessment viewpoints in the disturbance environment, For each evaluation viewpoint, values ​​corresponding to the plurality of parameters measured in the disturbance environment for each of the plurality of lighting devices are substituted into the formula (1) to obtain P ＤＧＲ and calculating a plurality of P ＤＧＲ Among them, P showing the maximum value ＤＧＲ and P indicating the multiple maximum values ​​respectively identified at the multiple evaluation viewpoints. ＤＧＲ and determining the specified value by specifying a luminous intensity value that is a limit at which discomfort glare is tolerable from the results of the plurality of subjective evaluations.

6. A lighting device according to claim 5.

7. The subjective evaluation data includes data obtained in a plurality of disturbance environments having different design illuminances. A lighting fixture according to any one of claims 3 to 6.

8. A lighting fixture applied to a facility where an event is held, The facility is a stadium or ground where the event related to a ball game is held.

2. A lighting fixture according to claim 1.

9. A method for designing a lighting fixture, comprising the steps of: An acquisition step of acquiring subjective evaluation data on discomfort glare from a subject in a disturbance environment having a lighting facility; a determination step of determining a prescribed value by obtaining correlation information regarding a correlation between the subjective evaluation data and an evaluation model regarding discomfort glare; a setting step of setting the illumination light emitted from the light source unit of the lighting fixture so that the fixture efficiency is greater than 60% and the luminous intensity value satisfies at least one of a first condition, a second condition, and a third condition; Including, The first condition is that the luminous intensity value is equal to or less than 1600 [cd / 1000lm] as the specified value when viewed from a viewpoint 8 degrees above the optical axis of the lighting device, The second condition is that the luminous intensity value is equal to or less than 600 [cd / 1000lm] as the specified value at a viewpoint 10 degrees above the optical axis, The third condition is that the luminous intensity value is equal to or less than 200 [cd / 1000lm] as the specified value at a viewpoint 12 degrees above the optical axis. Design method.

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