Building and lighting design method

Abstract

To reduce reflection on a window viewed from an observation position of a guard chamber, by a simple calculation expression assuming the situations of the guard chamber and an outdoor space.SOLUTION: A building (1) includes a guard chamber (2) having a window (20) and a back face wall (22) facing the window, and an outdoor space (3) adjacent to the guard chamber through the window, wherein an indoor lighting fixture (41) and an outdoor lighting fixture (42) are provided in each of the guard chamber and the outdoor space. The building is adjusted so that a light quantity of window reflection light, which is the total of a light quantity of first reflection light (Li1), which is formed by the light of the indoor lighting fixture being reflected on a window and reaching an observation position (50) in the guard chamber and the light quantity of second reflection light (Li2), which is formed by the light of the indoor lighting fixture being reflected in order on the back face wall and the window and reaching the observation position, becomes smaller than a light quantity of virtual transmission light (Lo2), which is formed by reflecting the light of the outdoor lighting fixture on an observation object (P2) in the outdoor space, and then transmitting through the window and reaching the observation position.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a building and a lighting design method, and more particularly to a building equipped with a guard room and a lighting design method for the building. [Background technology]

[0002] The brightness of lighting fixtures in guard rooms is generally determined by the recommended illuminance of the JIS standard. Guard rooms are equipped with windows, and observers (guards) in the guard room monitor the outdoor space (for example, the outdoor space under the eaves) through the windows. The brightness of lighting fixtures installed in the outdoor space is generally designed to be darker than the lighting fixtures in the guard room.

[0003] JP 2020-180511 A (Patent Document 1) discloses a house comprising a room with a first window, a first courtyard facing the first window, a first lighting that irradiates light into the first courtyard, a second window facing the first window across the room, a second courtyard facing the second window, and a second lighting that irradiates light into the second courtyard, wherein the illuminance of the first courtyard or the second courtyard is greater than the illuminance inside the room. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-180511 A Summary of the Invention [Problem to be solved by the invention]

[0005] The observer in the guard room is responsible for checking whether there are visitors through the window, but when looking outside at night, reflections occur on the window (glass surface), making it difficult to see the visitor. Therefore, there was a need for technology to suppress the reflection of the view from inside the guard room on the window.

[0006] In Patent Document 1, the illuminance of the courtyard is made greater than that of the living room so that the courtyard can be appreciated even at night, but such a residential lighting design cannot be directly applied to the lighting design of a guard room. This is because a guard room is smaller than a residential room, and if the outdoor space to be observed is an outdoor space, there is nothing (such as a wall) to reflect light behind the visitor, making reflections more likely to occur.

[0007] The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a building in which reflections on windows as seen from the observation position of the guard room are reduced by using a simple calculation formula that takes into account the conditions of the guard room and the outdoor space.

[0008] Another object of the present invention is to provide a lighting design method capable of reducing reflections by using a simple calculation formula. [Means for solving the problem]

[0009] A building according to one aspect of the present invention comprises a guard room having a window and a back wall facing the window, and an outdoor space adjacent to the guard room via the window, and an indoor lighting fixture and an outdoor lighting fixture are provided in the guard room and the outdoor space, respectively. This building is characterized in that the amount of window reflected light, which is the sum of the amount of first reflected light of light from the indoor lighting fixture reflected by the window to reach an observation position in the guard room and the amount of second reflected light of light from the indoor lighting fixture reflected by the back wall and the window in that order to reach the observation position, is adjusted to be smaller than the amount of virtual transmitted light of light from the outdoor lighting fixture reflected by an object to be observed in the outdoor space, transmitted through the window to reach the observation position.

[0010] Preferably, the reflectance of the observation object used in calculating the amount of virtual transmitted light is set within a range of 0.1 to 0.5.

[0011] The outdoor space is, for example, an outdoor space under the eaves. In this case, the outdoor lighting fixture is preferably one or more downlights provided in the eaves ceiling.

[0012] A lighting design method according to an aspect of the present invention is a lighting design method for a building including a guard room having a window and a back wall facing the window, and an outdoor space adjacent to the guard room via the window, and includes a first calculation step, a second calculation step, and an adjustment step. In the first calculation step, a sum of a first reflected light amount of light from an indoor lighting fixture installed in the guard room that is reflected by the window and reaches an observation position in the guard room, and a second reflected light amount of light from the indoor lighting fixture that is reflected by the back wall and the window in this order and reaches the observation position is calculated as the window reflected light amount using a first calculation formula. In the second calculation step, a virtual transmitted light amount of light from an outdoor lighting fixture installed in the outdoor space that is reflected by the window on an observation target in the outdoor space and then passes through the window and reaches the observation position is calculated using a second calculation formula. In the adjustment step, at least one of the luminous flux of the indoor lighting fixture, the reflectance or transmittance of the window, the reflectance of the rear wall, and the luminous flux of the outdoor lighting fixture is adjusted so that the amount of light reflected from the window is smaller than the amount of light of the virtual transmitted light. Effect of the Invention

[0013] According to the building of the present invention, the reflection on the window as seen from the observation room of the guard room is reduced, so that the observer stationed at the observation position can perform guard duties comfortably.

[0014] Furthermore, according to the lighting design method of the present invention, by using a simplified calculation formula that assumes the conditions of the guard room and the outdoor space, it is possible to easily reduce reflections on the window as seen from the observation position in the guard room. [Brief description of the drawings]

[0015] [Figure 1] 1 is a plan view showing a schematic view of a main part of a building according to an embodiment of the present invention. [Diagram 2] 1 is a cross-sectional view showing a schematic view of a main part of a building according to an embodiment of the present invention. [Diagram 3] 4 is a flowchart showing an example of a lighting design method for a building according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters and their description will not be repeated.

[0017] (About the building) An overview of a building 1 equipped with a guard room 2 and an outdoor space 3 will be described with reference to Figures 1 and 2. Figure 1 is a plan view that shows a schematic representation of the main parts of the building 1, and Figure 2 is a cross-sectional view that shows a schematic representation of the main parts of the building 1. Arrow A1 in Figures 1 and 2 indicates the depth direction of the guard room 2, and arrow A2 indicates the width direction (left-right direction) of the guard room 2.

[0018] As shown in FIG. 1, the guard room 2 is rectangular in plan view and is surrounded on all four sides by a front wall 21 with a window 20, a back wall 22 facing the front wall 21, and a pair of side walls 23, 24 facing each other. A door 25 leading to the outdoor space 3 may be provided on one of the pair of side walls 23, 24 (side wall 23). The building 1 may include another room adjacent to at least one wall (the back wall 22 or one of the pair of side walls 23, 24) other than the front wall 21 of the guard room 2, and as an example, the back wall 22 may have a door for entering and exiting the other room (not shown). Such a building 1 may be a guard building built independently on the premises of a factory or the like, or may be a tenant building, facility, hospital, apartment building, etc. that has multiple rooms other than the guard room 2.

[0019] The guard room 2 is narrower than a typical room (living room), and the depth from the front wall 21 to the back wall 22 is usually about 1 to 2 meters. The depth and width of the guard room 2 are expected to be no more than 3 meters. The outdoor space 3 is provided adjacent to the window 20. The window 20 is typically a waist-high window at least a portion of which can be opened and closed. In this embodiment, the outdoor space 3 is the space below the eaves portion 30 that protrudes from the upper end of the front wall 21 to the outdoors, that is, the eaves space. In this case, at least the front wall 21 of the front wall 21 is an exterior wall. Hereinafter, the outdoor space 3 will be referred to as the eaves space 3.

[0020] As shown in FIG. 2, a lighting fixture (hereinafter also referred to as "indoor lighting fixture") 41 is provided on the ceiling 26 of the guard room 2. The indoor lighting fixture 41 is, for example, composed of a horizontally long LED light extending along the width direction of the guard room 2 (the horizontal width direction of the window 20). The indoor lighting fixture 41 is provided in the center of the guard room 2 in the depth direction. A lighting fixture (hereinafter also referred to as "outdoor lighting fixture") 42 is provided on the ceiling of the eaves portion 30, i.e., the eaves ceiling 31. The outdoor lighting fixture 42 is composed of one or more downlights. Note that the indoor lighting fixture 41 may also be composed of multiple downlights, etc.

[0021] As shown in FIG. 1, the guard room 2 and the outdoor space 3 are provided with counter desks 51 and 52, respectively, on either side of the window 20. The counter desks 51 and 52 may be shelves directly attached to the front wall 21, or may be desks or the like installed on the floor. An observation position 50 where an observer is always present in the guard room 2 is a position in front of the counter desk 51, that is, a central position in the depth direction of the guard room 2. The observer, for example, sits down at the observation position 50 and observes the under-eaves space 3 through the window 20. It is assumed that the indoor lighting fixture 41 is installed directly above the observation position 50. It is assumed that fixtures (cabinets, copy machines, etc.) (not shown) are placed on the floor around the observation position 50.

[0022] In a building with a typical lighting design, when an observer P1 shown in FIG. 2 looks at the eaves space 3 through the window 20 from the observation position 50 at night, reflections on the window 20 are likely to occur. This is because the depth of the guard room 2 is narrow, and the impact of reflected light from the rear wall 22 is significant. Furthermore, if there is nothing (such as a wall) that reflects light further outside the eaves space 3 (to the rear of the visitor P2), reflections on the window 20 are even more likely to occur. The building 1 of this embodiment has a lighting design that assumes (takes into account) the situation of the guard room 2 and the eaves space 3.

[0023] (Lighting design method) A lighting design method for a building 1 according to this embodiment will be described with reference to Fig. 2. Fig. 2 shows a schematic diagram of a first reflected light Li1, a second reflected light Li2, and a transmitted light Lo2 that enter the eye of an observer P1 in the guard room 2 when a visitor P2 arrives in the eaves space 3.

[0024] The first reflected light Li1 is light that is light Li from the indoor lighting fixtures 41 that is reflected by the window 20 and reaches the observation position 50 (enters the eyes of the observer P1). The second reflected light Li2 is light that is light Li from the indoor lighting fixtures 41 that is reflected by the rear wall 22 and then the window 20 and reaches the observation position 50. The transmitted light Lo2 is light that is reflected light Lo1 from the outdoor lighting fixtures 42 that is reflected by a visitor (person being observed) P2 who appears in the eaves space 3, and then passes through the window 20 to reach the observation position 50.

[0025] It is desirable to calculate the size (intensity) of each light, i.e., the amount of light, based on the luminous flux method. In the following explanation, "amount of light" refers to "luminous flux (unit: lm)."

[0026] The amount of the first reflected light Li1 can be calculated based on the luminous flux of the indoor lighting fixtures 41 and the reflectance of the window 20. The amount of the second reflected light Li2 can be calculated based on the luminous flux of the indoor lighting fixtures 41, the reflectance of the window 20, and the reflectance of the back wall 22. The amount of the transmitted light Lo2 can be calculated based on the luminous flux of the outdoor lighting fixtures 42, the reflectance of the visitor P2 who is the object of observation, and the transmittance of the window 20.

[0027] The lighting of building 1 is designed so that the amount of "window reflected light" (hereinafter referred to as "window reflected light amount"), which is the sum of the amount of first reflected light Li1 and the amount of second reflected light Li2 in the guard room 2, is smaller than the amount of transmitted light Lo2 from the eaves space 3 (hereinafter referred to as "window transmitted light amount").

[0028] Here, the reflectance of visitor (observed subject) P2 used to calculate the amount of light transmitted through the window varies depending on the color of clothing worn by visitor P2 (the lighter the color, the higher the reflectance), so an accurate value cannot be obtained at the lighting design stage. In this embodiment, to be on the safe side, we assume that visitor P2 wears dark-colored clothing (dark gray), and set the reflectance of visitor P2 to a constant of 0.2. The reflectance constant for visitor P2 can be set within the range of 0.1 to 0.5.

[0029] In this way, by using transmitted light (virtual transmitted light) Lo2 based on virtual reflected light Lo1 with the reflectance of visitor P2 set as a constant, a simple calculation formula for reducing glare can be provided. A case in which the brightness (luminous flux of outdoor lighting fixtures 42) of the eaves space 3 that can ultimately reduce glare is calculated using the simple calculation formula will be described with reference to Fig. 3. Fig. 3 is a flowchart showing an example of a lighting design method for building 1 according to this embodiment.

[0030] 3, first, the luminous flux (amount of light) "A (unit: lm)" of the lighting fixture 41 in the guard room 2 is determined (Step S1). In general lighting designs for guard rooms 2, a luminous flux that exceeds the calculation result according to the JIS standard is often selected for safety reasons, but it is desirable to set the luminous flux "A" to a value equivalent to the calculation result according to the JIS standard. As mentioned above, the guard room 2 has walls closer to each other than a general room, and the area of ​​the floor surface with low reflectivity becomes smaller when fixtures are placed, so it is believed that the calculation result according to the JIS standard will ensure sufficient brightness.

[0031] Next, the reflectance "a (unit: %)" of the rear wall 22 of the guard room 2 and the reflectance "b (unit: %)" of the window 20 are determined (specified) (steps S2, S3), and the amount of light reflected from the window (unit: lm) is calculated using the following calculation formula 1 (step S4: first calculation step).

[0032] Amount of light reflected from window = (A×a×b+A×b) Equation 1 For example, if the luminous flux A of the indoor lighting fixture 41 is 4200 lm, the reflectance a of the back wall is 60%, and the reflectance b of the window 20 is 15%, the amount of light reflected from the window is calculated to be 1008 lm ((4200×0.6×0.15+4200×0.15)=1008).

[0033] Next, the transmittance "c (unit: %)" of the window 20 of the guard room 2 is determined (specified) (step S5). The transmittance "c" of the window 20 is typically "100-b". If the luminous flux of the lighting fixture 42 in the eaves space 3 is "B (unit: lm)", the amount of light transmitted through the window (unit: lm), which is the amount of virtual transmitted light Lo2, can be calculated by the following calculation formula 2 (step S6: second calculation step).

[0034] Amount of light transmitted through window = (B × 0.2 × c) Equation 2 For example, if the transmittance c of the window 20 is 80% and the luminous flux of the outdoor lighting fixture 42 is "B", the amount of light transmitted through the window is calculated as 0.16B (B x 0.2 x 0.8 = 0.16B).

[0035] From the above-mentioned calculation formulas 1 and 2, the luminous flux B that satisfies the relationship of "amount of light reflected from the window > amount of light transmitted through the window" is calculated (step S7). The luminous flux B is calculated as a value greater than the calculated value of "A(a+b) / 0.2c". Based on the above example, the luminous flux B that satisfies "0.16B>1008" is calculated as a value greater than 6300 lm.

[0036] From the calculation results, the outdoor lighting fixture 42 that realizes a luminous flux B greater than the calculated value of "A(a+b) / 0.2c" (for example, 6300 lm) is determined (step S8). That is, the luminous flux B of the outdoor lighting fixture 42 is adjusted (adjustment step). For example, if it is difficult to change the specifications of the downlights that constitute the outdoor lighting fixture 42, the number of downlights is increased to adjust the luminous flux B.

[0037] As described above, in normal lighting design, the luminous flux A of the indoor lighting fixture 41 is designed to be brighter than necessary, and the luminous flux B of the outdoor lighting fixture 42 is designed to be the minimum necessary brightness, so that the amount of light reflected from the window is greater than the amount of light transmitted through the window, causing reflections. In contrast, in the present embodiment, reflections on the window 20 are reduced by selecting the luminous flux B of the outdoor lighting fixture 42 such that the amount of light transmitted through the window is greater than the amount of light reflected from the window. Therefore, even if a visitor P2 dressed in dark clothes arrives, the observer P1 in the guard room 2 can immediately notice the presence of the visitor P2, and can perform guard duties comfortably.

[0038] 3 shows a calculation method for determining the luminous flux A of the lighting fixture 41 in the guard room 2 and then calculating the luminous flux B of the lighting fixture 42 in the eaves space 3, but conversely, it is also possible to determine the luminous flux B of the lighting fixture 42 in the eaves space 3 and then calculate the luminous flux A of the lighting fixture 41 in the guard room 2 using the above-mentioned simplified calculation formula. Alternatively, it is also possible to determine the luminous fluxes A and B of the lighting fixtures 41 and 42 in the guard room 2 and the eaves space 3 and then calculate the reflectance of the rear wall 22 or the reflectance / transmittance of the window 20 that can achieve the above-mentioned light amount balance. In other words, according to this embodiment, at least one of the luminous flux of the indoor lighting fixture 41, the reflectance or transmittance of the window 20, the reflectance of the rear wall 22, and the luminous flux of the outdoor lighting fixture 42 can be adjusted so that the amount of light reflected from the window is smaller than the amount of light transmitted through the window.

[0039] The lighting design for the building 1 according to this embodiment can also be used to prevent glare in an existing guard room 2. As a simple measure against glare, anti-glare films capable of reducing the reflectance of windows are commercially available, but attaching anti-glare films may reduce the clarity of the window, which may interfere with the guard's work. For this reason, it is not desirable to apply anti-glare films to the windows 20 of the guard room 2. With the lighting design method according to this embodiment, it is possible to reduce glare on the windows 20 without intentionally changing the reflectance and transmittance of the windows 20.

[0040] The above-mentioned lighting design method may be realized by a computer having a processor and a memory. Such a computer includes an input unit that accepts input of numerical values ​​that are variables of the simplified calculation formula, and an output unit that outputs a result obtained by substituting the input numerical values ​​into the simplified calculation formula. This makes it possible to support the lighting design of the building 1.

[0041] In this embodiment, the outdoor space 3 is an outdoor space under the eaves, but is not limited to this example and may be, for example, an entrance hall or a corridor within the building 1.

[0042] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0043] 1 Building, 2 Guard room, 3 Outdoor space (eaves space), 20 Window, 21 Front wall, 22 Rear wall, 23, 24 Side walls, 26 Ceiling, 30 Eaves, 31 Eaves ceiling, 41 Indoor lighting fixture, 42 Outdoor lighting fixture, 50 Observation position, Li1 First reflected light, Li2 Second reflected light, Lo1 Virtual reflected light, Lo2 Virtual transmitted light, P1 Observer, P2 Visitor (observed subject).

Claims

1. a guard room having a window and a back wall facing the window and equipped with an indoor lighting fixture; an outdoor space adjacent to the guard room through the window and equipped with an outdoor lighting fixture; a light amount of the window reflected light, which is the sum of the amount of first reflected light of the light from the indoor lighting fixture being reflected by the window and reaching the observation position in the guard room and the amount of second reflected light of the light from the indoor lighting fixture being reflected by the rear wall and the window in that order and reaching the observation position, is adjusted to be smaller than the amount of virtual transmitted light of the light from the outdoor lighting fixture being reflected by an object to be observed in the outdoor space, passing through the window and reaching the observation position.

2. The building according to claim 1 , wherein the reflectance of the object to be observed used in calculating the amount of the virtual transmitted light is set within a range of 0.1 to 0.

5.

3. The outdoor space is an outdoor eaves space, The building according to claim 1 , wherein the outdoor lighting fixture is one or more downlights installed in a soffit.

4. A lighting design method for a building including a guard room having a window and a back wall facing the window, and an outdoor space adjacent to the guard room via the window, comprising: a first calculation step of calculating, using a first calculation formula, a sum of a first amount of reflected light of light from an indoor lighting fixture provided in the guard room that is reflected by the window and reaches an observation position in the guard room, and a second amount of reflected light of light from the indoor lighting fixture that is reflected by the rear wall and the window in this order and reaches the observation position, as an amount of window reflected light; a second calculation step of calculating, by a second calculation formula, an amount of virtual transmitted light that is transmitted through the window and reaches the observation position after light from an outdoor lighting device provided in the outdoor space is reflected by an observation target in the outdoor space through the window; and adjusting at least one of the luminous flux of the indoor lighting fixture, the reflectance or transmittance of the window, the reflectance of the rear wall, and the luminous flux of the outdoor lighting fixture so that the amount of light of the window reflected light is smaller than the amount of light of the virtual transmitted light.

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