Rainbow generating system and rainbow generating method

Abstract

A novel method for generating artificial rainbows. [Solution] The rainbow generating system 100 comprises an observation platform 10 having a predetermined height and a water sprinkler device 20. The water sprinkler device 20 sprinkles water toward the space in front of the observation platform 10 when the observer stands with their back to a light source such as the sun. This generates a rainbow that can be seen by an observer standing on the observation platform.

Description

[Technical Field]

[0001] The present invention relates to a system and method for generating an artificial rainbow. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there have been known devices capable of generating an artificial rainbow above the head of an observer.

[0003] For example, Patent Document 1 discloses a device that generates an artificial rainbow by using a fountain pump to spray water in an aquarium almost vertically and irradiating the water with white light from a lighting fixture.

[0004] Furthermore, Patent Document 2 discloses a system that generates an artificial rainbow by spraying water droplets under sunlight incidence conditions. The system in Patent Document 2 includes a water tank that stores water and can be pressurized by a pump, a spray nozzle body that can spray from a nozzle at the tip via a hose from the water tank, and a stand means that supports the spray nozzle body so that the spray is directed substantially upward from the nozzle of the spray nozzle body. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 61-198209 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-202163 Summary of the Invention [Problem to be solved by the invention]

[0006] Naturally occurring rainbows are generated using the sun as a light source, and appear to an observer on the ground as an arc-shaped rainbow in the sky. For this reason, the devices disclosed in Patent Documents 1 and 2 are both configured to generate a circular artificial rainbow above the observer's head by using a light source above the observer's head, similar to a natural rainbow. Patent Document 1 uses a lighting fixture as the light source for generating the artificial rainbow, while Patent Document 2 uses the sun.

[0007] It is also known that a rainbow is seen by an observer at a position that forms a visual angle of approximately 42° with respect to the "anti-solar point," which is on the opposite side of the light source on the line connecting the light source and the observer's eye. Therefore, if you try to artificially create a rainbow above an observer's head using a light source above their head, it is necessary to create a rainbow with a large radius, and the rainbow seen by the observer will have an arc-like shape.

[0008] Meanwhile, the inventors of the present invention have been studying a novel method for allowing an observer to see an artificial rainbow. However, as mentioned above, conventional rainbow generating devices only allow an observer to see an arc-shaped artificial rainbow that appears overhead, similar to a natural rainbow. Therefore, while conventional rainbow generating systems can surprise an observer by showing that a rainbow, which is a natural phenomenon and occurs rarely, is artificially generated, they have had the problem of being unable to surprise an observer with the novelty or uniqueness that is different from a natural rainbow.

[0009] Therefore, a main object of the present invention is to provide a novel technique for generating an artificial rainbow. [Means for solving the problem]

[0010] After extensive research into ways to solve the above problems, the inventors of the present invention have come up with the idea of ​​installing an observation platform on which an observer can climb, positioning a light source behind the platform, and spraying water into the space in front of the platform, thereby enabling the observer to observe an artificial rainbow from the platform. This has led to the discovery that it is possible to allow the observer to visually perceive a rainbow in a way that is different from conventional artificial rainbows. That is, depending on the observation conditions, the observer can observe a circular rainbow as if looking down on it. Based on this discovery, the inventors have come to the realization that the problems of the prior art can be solved, and have completed the present invention. Specifically, the present invention has the following configuration or steps.

[0011] A first aspect of the present invention relates to a rainbow generation system 100. The rainbow generation system 100 according to the present invention comprises an observation platform 10 having a predetermined height and water sprinkler means 20. The water sprinkler means 20 sprinkles water toward the space in front of the observation platform 10 when the observer stands with their back to a light source. This allows the rainbow generation system 100 to generate a rainbow that can be seen by an observer who has climbed onto the observation platform 10. The light source can be the sun or a lighting fixture. If the light source is a lighting fixture, the lighting fixture may also be included as part of the components of the rainbow generation system 100.

[0012] As described above, by placing the observation stand 10 with its back to the light source and sprinkling water on the front side of the observation stand 10, the observer can observe a rainbow generated near the space where the water is sprinkled from above the observation stand 10. In this case, the anti-solar point (the point on the line connecting the light source and the observer's eye, located opposite the light source from the observer's perspective) is located below the observer's eyes. Furthermore, since water is sprinkled around the anti-solar point, the observer can easily observe the rainbow by looking down on it. Furthermore, according to the configuration of the present invention, a rainbow with a relatively small radius centered on the anti-solar point is generated, making it easier for the observer to see the entire rainbow, and as a result, the observer can easily see a circular rainbow. While natural rainbows appear only as an arc in the sky from the observer's perspective, according to the present invention, a circular rainbow can be seen below the observer. In this way, the present invention can provide the observer with a new visual experience that is different from both naturally occurring rainbows and conventional artificial rainbows.

[0013] The rainbow generation system 100 according to the present invention is preferably configured to allow an observer to see a circular rainbow when the light source is located above the top surface of the observation stand 10. The top surface of the observation stand 10 is the location where the observer is expected to be standing or sitting when observing the rainbow. If the light source is the sun, then naturally the light source will be located above the top surface of the observation stand 10. Therefore, the condition that the light source be located above the top surface of the observation stand 10 applies when the light source is a lighting fixture.

[0014] In the rainbow generation system 100 according to the present invention, the water sprinkler means 20 preferably includes one or more elevated water sprinkler devices 21. The elevated water sprinkler devices 21 are configured to sprinkle water from a position higher than the top surface of the observation platform 10 toward the space in front of the observation platform 10. By providing such elevated water sprinkler devices 21, water droplets can be distributed in the space above and in front of the observation platform 10, making it possible to generate a rainbow at an optimal position depending on the position of the light source. In particular, during times such as the winter solstice when the sun's altitude is low, water sprinklers 21 can generate a rainbow at a position close to the observer's eye level, making the rainbow more clearly visible.

[0015] In the rainbow generating system 100 according to the present invention, the high elevation sprinkler device 21 is preferably configured to spray water sideways or downward. Spraying water sideways or downward means that the main direction of water sprayed from the high elevation sprinkler device 21 is parallel to the horizontal plane or at an angle inclined downward (for example, an angle between 0° and 90° relative to the horizontal plane). Spraying water sideways or downward from the high elevation sprinkler device 21 in this manner has the effect of preventing water droplets from being blown in unintended directions by the wind, especially when the system is installed outdoors. This allows water droplets to be stably distributed within a desired space, providing a stable, highly visible rainbow to the observer.

[0016] In the rainbow generating system 100 according to the present invention, the sprinkler means 20 preferably includes one or more low-altitude sprinkler devices 22. The low-altitude sprinkler devices 22 are configured to sprinkle water from a position lower than the top surface of the observation platform 10 toward the space in front of the observation platform 10. By providing such low-altitude sprinkler devices 22, water droplets can be distributed in the space below and in front of the observation platform 10. In particular, during the summer solstice, when the sun's altitude is high, water sprinkler devices 22 can generate rainbows at appropriate positions below the observer's line of sight, making it possible to consistently view rainbows regardless of the season or time of day. Furthermore, by using a combination of high-altitude sprinkler devices 21 and low-altitude sprinkler devices 22, water droplets can be distributed over a wider area, enabling rainbows to be generated under a variety of observation conditions.

[0017] In the rainbow generating system 100 according to the present invention, the low sprinkler device 22 is preferably configured to spray water upward. Spraying water upward means that the main direction of the water sprayed from the low sprinkler device 22 is sprayed at an angle inclined upward with respect to the horizontal (for example, an angle greater than 0° and less than 90° with respect to the horizontal). By spraying water upward from the low sprinkler device 22 in this manner, water droplets can be distributed over a wide area from the bottom to the top of the space in front of the observation platform 10. Furthermore, because the water droplets sprayed upward from the low sprinkler device 22 follow a parabolic trajectory, rising and then falling, they remain in the space for a certain period of time, ensuring stable rainbow visibility.

[0018] In the rainbow generation system 100 according to the present invention, the water sprinkler means 20 preferably also sprinkles water toward the space at the feet of the observation stand 10 or the space behind the observation stand 10 when the observer is standing with his or her back to the light source. By sprinkling water near the feet of the observation stand 10 in this manner, water droplets can be distributed near the observer's feet, particularly around the summer solstice when the sun's altitude is high, making it easier to generate a circular rainbow centered on the point of sunshine. Furthermore, by sprinkling water on the back side of the observation stand 10, water droplets are distributed 360 degrees around the observer, providing a more immersive rainbow observation experience.

[0019] The rainbow generating system 100 of the present invention preferably further includes a dark-colored litter 40. The litter 40 is installed on the bottom surface of the space into which the water sprinkler 20 sprinkles water. In this specification, "dark color" refers to a color with an L* value of 40 or less in the CIE-L*a*b* color system. By installing such a dark-colored litter 40 on the ground or floor of the space, the background of the rainbow formed by the sprinkled water droplets becomes dark, making the colors of the rainbow more clearly visible. In other words, the greater the contrast between the rainbow and the background, the more visible it becomes. Therefore, by using a dark-colored litter 40, the viewer can more clearly see the colorful rainbow. Furthermore, by using a dark-colored litter 40 on the bottom surface, it is possible to prevent light, such as sunlight, from reflecting off the bottom surface and forming complex optical paths within the water droplets, which is expected to make the colors of the rainbow more vivid.

[0020] The rainbow generating system 100 according to the present invention preferably further includes a shielding wall 50 that is at least partially dark in color. The shielding wall 50 is erected at the rear of the space into which the sprinkler means 20 sprinkles water, as viewed from the observation platform 10. By providing such a shielding wall 50, the background of the rainbow formed by the sprinklered water droplets becomes dark, making the colors of the rainbow stand out more clearly. In particular, when the solar altitude is low, installing the shielding wall 50 at the rear of the sprinkler space ensures a dark background in the observer's line of sight, thereby improving the contrast of the rainbow. Furthermore, the shielding wall 50 also functions as a windbreak, which can be expected to have the secondary effect of reducing the influence of external wind and stabilizing the distribution of water droplets.

[0021] A second aspect of the present invention relates to a rainbow generating method, in which water is sprayed toward the space in front of an observation stand 10 when the observer stands with his back to a light source, thereby generating a rainbow that is visible to an observer standing on the observation stand 10. [Effects of the Invention]

[0022] According to the present invention, a rainbow can be artificially generated in a novel manner. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic diagram showing the principle of generating an artificial rainbow according to the present invention. [Figure 2] FIG. 2 is a side view of a rainbow generating system according to one embodiment of the present invention. [Figure 3] FIG. 3 is a schematic diagram showing the arrangement of the water sprinkling means and the direction of water spray in a rainbow generating system according to one embodiment of the present invention. [Figure 4] FIG. 4 shows the position of rainbow formation and the required range of dark background according to seasonal changes in the solar altitude in a rainbow generation system according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and includes appropriate modifications of the embodiments described below within the scope obvious to those skilled in the art.

[0025] First, the principle of a rainbow generation system 100 according to the present invention will be described with reference to FIG. 1. As shown in FIG. 1, the rainbow generation system 100 basically comprises an observation platform 10 and a water sprinkling means 20. An observer can climb onto the observation platform 10 and stand on the top surface of the platform 10 to observe a rainbow. The observation platform 10 is installed between a light source and a space in which a rainbow is to be generated (i.e., a space in which water is sprinkled). In other words, the observation platform 10 is arranged so that the light source is located on its rear side and the water sprinkling space is located on its front side. The rainbow generation system 100 may be installed either indoors or outdoors.

[0026] In the present invention, as shown in FIG. 1, the sun is basically used as a light source, and it is assumed that the rainbow generating system 100 is installed outdoors. Also, as shown in FIG. 1, the water sprinkler means 20 sprinkles water toward the space in front of the observation stand 10. The arrangement of the water sprinkler means 20 is not particularly limited, but it is preferable that water be sprayed from multiple locations in order to efficiently distribute water droplets over a wide area in front of the observation stand 10. In this way, by spraying water toward the front side of the observer in response to light irradiated from behind the observer, the water droplets distributed in the space reflect the light, generating a rainbow. This rainbow is observed by the observer standing on the observation stand 10.

[0027] As shown in FIG. 1, a rainbow appears to appear at a position that forms a visual angle of approximately 42° with respect to the line connecting the light source and the observer's eye, centered at the point of anti-solar light, which is located on the line connecting the light source and the observer's eye. In the present invention, the observer observes the rainbow from a height of approximately 3 to 4 meters above the ground, so the anti-solar light is located below the observer. Furthermore, the space between the observer's eye level and the ground is open, and water droplets are scattered in this space, so a rainbow with a relatively small radius appears in this space. If the observer is standing on the ground, the space between eye level and the ground is insufficient, making it difficult to see a rainbow even if water droplets are scattered. However, by standing on high ground and looking down into the space where water droplets are scattered, as in the present invention, the observer can more easily see the rainbow that appears in that space. In particular, under the right conditions, the observer can observe a beautiful circular rainbow by looking down from the observation platform 10.

[0028] The height of the observation platform 10 affects the shape and size of the visible rainbow. Generally, a rainbow forms at an angle of approximately 42° from the anti-solar point. Therefore, the higher the observation platform 10, the greater the distance from the anti-solar point to the observer, resulting in a larger visible portion of the rainbow's circle. For example, if the observation platform 10 is 1 m high, the observer's eye height is approximately 2.5 to 3 m above the ground. Looking down from this height, only the upper portion of the rainbow, with a smaller radius centered on the anti-solar point, is often visible. On the other hand, if the observation platform 10 is 2 m high, the observer's eye height is approximately 3.5 to 4 m above the ground, allowing a wider view down, making it possible to observe a larger portion of the rainbow centered on the anti-solar point, ideally a complete circular rainbow.

[0029] Furthermore, while the example shown in FIG. 1 uses the sun as the light source, a lighting fixture can also be used instead. In this case, a surface light source that emits white parallel light with a continuous spectrum similar to that of sunlight is recommended. For example, an LED light with a spectrum similar to that of sunlight is suitable. The lighting fixture should be positioned above and behind the observer, just like the sun. Specifically, the lighting fixture should be installed behind the observation platform 10 and positioned so that it emits light from above the observer's head toward the water sprinkling space. It is recommended to use a lighting fixture with sufficient light output (for example, 10,000 lumens or more). Insufficient light output may result in the rainbow being dark and the colors being unclear.

[0030] Next, one embodiment of a rainbow generating system 100 according to the present invention will be described with reference to Figures 2 to 4. As shown in Figure 2, the rainbow generating system 100 according to this embodiment includes, in addition to an observation platform 10 and a watering means 20, a support 30, a bedding material 40, a shielding wall 50, shielding plants 60, and a motion sensor 70.

[0031] As described above, the observation platform 10 is a platform on which an observer climbs to observe a rainbow. The height of the observation platform 10 from the ground to the top surface (the surface on which the observer climbs) is preferably, for example, 1 m or more, and more preferably 1.5 m or more or 2.0 m or more. If the top surface is less than 1 m high, the observer's line of sight is not elevated sufficiently above the ground, making it difficult to fully observe the circular rainbow centered on the anti-solar point. On the other hand, there is no particular upper limit on the height of the top surface. As the height of the top surface increases, it becomes easier for observers to see rainbows with larger radii. However, considering the safety of observers climbing to the top surface, it is preferable that the height of the top surface be 5 m or less. In particular, if the height of the top surface is in the range of 1.5 to 2.5 m, the observer's eye height will be approximately 3 to 4 m above the ground, considering the average adult height (1.5 to 2 m), which is the optimal height for observing a rainbow. At this height, the circular rainbow centered on the anti-solar point can be observed with a good viewing angle.

[0032] Furthermore, a structure with stairs or a slope made of a solid material such as metal, concrete, or wood is suitable as the observation platform 10. In the example shown in FIG. 2, a movable workbench is used as the observation platform 10. By using a movable platform as the observation platform 10 in this way, it becomes easier to change the orientation and position of the observation platform 10 according to the position of the sun depending on the season and time of day. Furthermore, it is desirable to ensure that the top surface of the observation platform 10 is large enough (for example, approximately 2 to 4 m wide and 1 to 2 m deep) so that an observer can stand safely and observe the rainbow. Furthermore, it is advisable to provide handrails around the perimeter of the top surface to ensure the observer's safety.

[0033] Furthermore, the position of the observation stand 10 can be adjusted to accommodate changes in the sun's altitude at meridian. For greater versatility, it is common to install the observation stand 10 with its front side facing south and its back side facing north. When installed in this manner, rainbows can be best observed from the observation stand 10 when the sun is at meridian. However, depending on the environment of the installation location and the time of use, it is also possible to install the observation stand 10 with its front side facing east or west.

[0034] The sprinkler means 20 is a means for spraying water into the space where a rainbow is to be generated. As mentioned above, the space where a rainbow is to be generated is the space in front of the observation platform 10 when the observer has their back to the light source. The space where water is sprayed by the sprinkler means 20 is also referred to as the "sprinkler space." As mentioned above, a rainbow occurs around the anti-solar point. For this reason, it is preferable to estimate the anti-solar point based on the eye position of the observer standing on the observation platform 10 and the solar noon altitude depending on the season, and then spray water from multiple locations so that water is sprayed around the anti-solar point. As the solar orbit changes with the season, the estimated anti-solar point also changes. In this embodiment, the arrangement and spray direction of multiple sprinkler devices are adjusted to accommodate all seasons.

[0035] Commonly used watering devices, such as garden or agricultural sprayers, fountains, and mist generators, can be used. Specifically, a watering device preferably combines a pump that provides the appropriate water pressure for spraying water with a nozzle that can adjust the direction and amount of water sprayed. The pump can be, for example, a submersible pump or a land-based pump with an output of approximately 0.75 to 3.7 kW. The nozzle can be, for example, a sprinkler-type nozzle with an adjustable spray angle or a mist-type nozzle that generates fine water droplets. To produce a particularly vivid rainbow, it is preferable to select a nozzle that produces water droplets with a diameter of approximately 0.1 to 2 mm. If the droplets are too small, the light refraction and reflection efficiency decreases. If they are too large, the droplets fall too quickly, shortening their residence time in the watering space and preventing the droplets from maintaining their spherical shape. Therefore, a droplet diameter of 0.5 to 1 mm is particularly preferable. A flow control valve for adjusting the amount of water supplied or a control mechanism that can automatically change the watering pattern according to wind direction and speed may also be provided. The sprinkler system may be equipped with a water storage tank or may be configured to draw water directly from the water supply system.

[0036] 2 and 3 schematically show the arrangement and water spray direction of each sprinkler device (21, 22, 23) used as the sprinkler means 20 in this embodiment. In this embodiment, the sprinkler means 20 includes a first high-altitude sprinkler device 21(a), a second high-altitude sprinkler device 21(b), a first low-altitude sprinkler device 22(a), a second low-altitude sprinkler device 22(b), and a rear sprinkler device 23. Note that the position of each sprinkler device shown in FIGS. 2 and 3 indicates the position of the water spray outlet (nozzle) of each sprinkler device, and other components such as pumps, tanks, and water supply pipes may be located in different locations. Furthermore, the pumps, tanks, water supply pipes, etc. of each sprinkler device may be shared by multiple sprinkler devices.

[0037] The first high elevation sprinkler system 21(a) and the second high elevation sprinkler system 21(b) have their nozzles positioned above the top surface of the observation platform 10. In order to raise the nozzles of each high elevation sprinkler system 21(a, b), multiple support pillars 30(a, b) are erected on the front side of the observation platform 10. In this embodiment, the first support pillar 30(a) is erected on the left side of the front side of the observation platform 10, and the second support pillar 30(b) is erected on the right side of the front side of the observation platform 10. The distance between the first support pillar 30(a) and the second support pillar 30(b) should be at least 2 m or more, preferably 3 to 12 m, and particularly preferably 5 to 8 m. The nozzle of the first high-altitude sprinkler system 21(a) is attached to the first support 30(a), and the nozzle of the second high-altitude sprinkler system 21(b) is attached to the second support 30(b). The height at which the nozzles of each high-altitude sprinkler system 21(a, b) are attached must be at least higher than the top surface of the observation platform 10, but is preferably higher than the eye level of spectators standing on the top surface of the observation platform 10 (e.g., the height of the top surface plus an average height of 1.5 m). Specifically, the height of the nozzles of each high-altitude sprinkler system 21(a, b) is preferably 2.5 m or more above ground level, with 3 to 6 m or 3.5 to 5 m being particularly preferred. This height range is sufficiently higher than the height of the observer's line of sight and is suitable for effectively distributing water throughout the sprinkler space. However, since a too high height makes the system susceptible to wind, it is desirable to avoid installation above 6 m.

[0038] Furthermore, the horizontal distance from the observation platform 10 to the support 30 (the support to which the high-altitude sprinkler system 21 is attached) must be determined taking into consideration the rainbow formation position and visibility. In this embodiment, when viewed from the side as shown in Figure 2, the horizontal distance from the observation platform 10 to each support 30 (a, b) is preferably approximately 1 to 8 m, and particularly preferably 2 to 5 m. This distance range allows for the creation of a rainbow of appropriate size and visibility for the observer. If the distance is too close, water droplets may splash onto the observer; if the distance is too far, the water droplets may not reach the observer, making the rainbow difficult to see. Furthermore, this distance range can be set taking into consideration the geometry of the rainbow formed at an angle of approximately 42° with respect to the position of the sun.

[0039] 2 and 3, each of the support columns 30(a, b) and each of the high altitude sprinkler devices 21(a, b) are installed at the back of the space where the rainbow is generated (i.e., the sprinkler space) when viewed from the observation platform 10. In other words, water is sprayed in a fan shape from the nozzles of the high altitude sprinkler devices 21(a, b) toward the space between the observation platform 10 and each of the support columns 30. For this reason, in this embodiment, each of the high altitude sprinkler devices 21(a, b) sprays water toward the triangular space formed by connecting the observation platform 10 and each of the support columns 30.

[0040] As shown in the enlarged portion of Figure 3, the nozzles of each high elevation sprinkler device 21(a, b) preferably spray water almost horizontally or downward. While the spray angle of each nozzle of each high elevation sprinkler device 21(a, b) is not particularly limited, it is preferably in the range of 45 to 90 degrees, particularly 60 to 80 degrees, so that the water is sprayed horizontally or downward relative to the horizontal plane. This spray angle allows the sprayed water droplets to fall in an appropriate parabolic arc, allowing them to remain in the sprinkler space for a longer period of time and reach the observer. Furthermore, this horizontal or downward spray configuration minimizes the scattering of water droplets due to wind, enabling the formation of a stable rainbow. This arrangement and spray direction allows water droplets to be distributed over a wide area, from the upper to the middle of the space in front of the observation platform 10.

[0041] The first low-altitude sprinkler device 22(a) and the second low-altitude sprinkler device 22(b) have their nozzles positioned lower than the top surface of the observation platform 10. In this embodiment, the nozzles of each low-altitude sprinkler device 22(a, b) are attached to a location below the top surface of the observation platform 10. Specifically, the first low-altitude sprinkler device 22(a) is attached to the left of the front of the observation platform 10, and the second low-altitude sprinkler device 22(b) is attached to the right of the front of the observation platform 10. The height of the nozzles of each low-altitude sprinkler device 22(a, b) from the ground surface is preferably within the range of 0.1 to 1.0 m, and particularly preferably within the range of 0.3 to 0.5 m. This height range is less susceptible to wind, allows water to be sprayed appropriately from the bottom of the observation platform 10, and prevents excessive water from accumulating at the bottom of the sprinkler space. The horizontal position of the nozzle of each low location sprinkler device 22(a, b) is preferably 0.5 to 2 m to the left and right of the center of the observation platform 10. This allows water droplets to be distributed effectively in the lower part of the space in front of the observation platform 10.

[0042] 2 and 3, water is sprayed in a fan shape from the nozzles of each low elevation sprinkler device 22(a, b) toward the space that generates the rainbow (i.e., the sprinkler space) located behind the device when viewed from the observation platform 10. In other words, water is also sprayed from the nozzles of the low elevation sprinkler devices 22(a, b) toward the space between the observation platform 10 and each support 30.

[0043] As shown in the enlarged portion of Figure 3, it is preferable to spray water upward from the nozzles of each low-altitude sprinkler device 22(a, b). While the spray angle of the nozzles of each low-altitude sprinkler device 22(a, b) is not particularly limited, it is preferably in the range of 20 to 80 degrees, particularly 30 to 60 degrees, so that the water is sprayed upward relative to the horizontal plane. This spray angle allows the sprayed water droplets to rise and fall in an appropriate parabolic arc, allowing them to remain in the sprinkler space for a longer period of time. Allowing the sprayed water droplets to fall freely also helps maintain the spherical shape of the water droplets. Furthermore, the upward spray configuration allows the water droplets to be distributed over a wide area, from the lower to the middle of the sprinkler space. Using this arrangement and spray direction in combination with the high-altitude sprinkler device 21(a, b) and the low-altitude sprinkler device 22(a, b), it is possible to uniformly distribute water droplets throughout the sprinkler space, ensuring clearer and more consistent rainbow visibility.

[0044] Unlike the high elevation sprinkler system 21 and low elevation sprinkler system 22 described above, the rear sprinkler system 23 is provided mainly to sprinkle water on the feet and rear side of the observation platform 10. As shown in FIG. 2, for example, the rear sprinkler system 23 is installed on the observation platform 10. Like the low elevation sprinkler system 22, the nozzles of the rear sprinkler system 23 are positioned lower than the top surface of the observation platform 10. Specifically, the height of the nozzles of the rear sprinkler system 23 from the ground surface is preferably within the range of 0.1 to 1.0 m, and particularly preferably within the range of 0.3 to 0.5 m. This height range makes it less susceptible to wind and prevents water droplets from splashing on observers, while effectively distributing water droplets around the observation platform 10.

[0045] By spraying water from the rear sprinkler device 23 in a fan shape that surrounds the feet of the observation platform 10, water droplets can be distributed directly below the observer. In addition, by spraying water toward the rear side of the observation platform 10, water droplets can be distributed in a 360-degree space around the observer. This makes it possible to distribute water droplets around the point of the sun even when the point of the sun is located near the observer's feet, such as during the summer solstice when the sun's altitude is high, and a circular rainbow can be formed.

[0046] The spray angle of water from the nozzles of the rear sprinkler system 23 is not particularly limited, and the spray angle can be adjusted so as to prevent water from splashing on the observer. For example, the spray angle of the rear sprinkler system 23 may be parallel to the horizontal plane or tilted slightly downward relative to the horizontal plane. The spray angle of the rear sprinkler system 23 is preferably in the range of 5 to 45 degrees, particularly 10 to 30 degrees, so that the water is directed downward relative to the horizontal plane. Furthermore, it is preferable that the water be sprayed in a fan-like pattern in the range of 90 to 180 degrees from the observation platform 10 as the center in the horizontal direction. This spray angle allows water droplets to be distributed over a wide area, from the feet to the rear side of the observation platform 10. By combining the high elevation sprinkler system 21, the low elevation sprinkler system 22, and the rear sprinkler system 23 with such an arrangement and spray direction, a stable circular rainbow can be generated regardless of changes in the solar altitude.

[0047] The floor covering 40 is a component laid on the ground in an area where the rainbow can be seen primarily by an observer standing on the observation platform 10. A dark-colored floor covering 40 is used, which serves as a background when the observer views the rainbow, thereby highlighting the colors of the rainbow as seen by the observer. Therefore, the floor covering 40 is preferably placed so as to surround the periphery of the observation platform 10, particularly so as to be widely spread in front of the observation platform 10. In this embodiment, the observation platform 10 is placed on the floor covering 40. As mentioned above, the term "dark color" in this specification refers to a color with an L* value of 40 or less in the CIE-L*a*b* color system. Specifically, this includes black, dark gray, dark blue, dark green, and dark brown. In this embodiment, a dark-colored stone slab is used as the floor covering 40. The floor covering 40 may be composed of multiple rectangular porcelain or stone panels, or a single large panel. Furthermore, the flooring 40 is not limited to plate-shaped materials, and gravel or other irregularly shaped dark materials can also be scattered. Furthermore, the flooring 40 is not limited to porcelain or stone, and can be made from processed known materials such as wood, metal, or resin. However, since metal flooring 40 can be slippery when water accumulates on it, and wood flooring has the disadvantage of being prone to rot, it is recommended that the flooring be made of porcelain or stone. The flooring 40 is preferably large enough to cover at least the entire bottom surface of the space where the rainbow will occur, and specifically, it is desirable that the flooring 40 be large enough to cover an area of ​​approximately 5 to 15 meters from the front of the observation platform 10.

[0048] The plan view of Figure 4 shows the installation position of the observation platform 10 and the watering areas of each sprinkler device 21, 22, and 23, with the flooring 40 at the center. It also shows a circular rainbow that is expected to be visible to an observer standing on the observation platform 10. In particular, Figure 4(a) shows a rainbow that appears on the winter solstice (the day when the sun's altitude at noon is lowest), Figure 4(b) shows a rainbow that appears on the vernal or autumnal equinox (the day when the length of day and night is approximately equal), and Figure 4(c) shows a rainbow that appears on the summer solstice (the day when the sun's altitude at noon is highest). Similarly, Figure 2 also shows rainbows that appear on the winter solstice, vernal or autumnal equinox, and summer solstice. Thus, when the sun is used as a light source, the position of the rainbow seen by the observer varies depending on the season. On the other hand, it is difficult to adjust the position and range of the flooring 40 depending on the season, especially when it is made of stone. For this reason, in this embodiment, the range in which a rainbow can be seen for each season is estimated, and the installation range and position of the litter 40 are determined so that the litter 40 can be seen as the background to the rainbow in any season. Specifically, Figures 4(a) to 4(c) show the location where a rainbow can be seen in each season and the "area requiring a dark color" as the background (dash-dotted line). The shape and installation position of the litter 40 are then determined so as to encompass the "area requiring a dark color" in all seasons. Specifically, in this embodiment, the litter 40 is shaped to have an arc-shaped edge portion formed in a parabolic shape with its apex located in front of the observation platform 10 and linear edge portions connecting both ends of this arc-shaped edge portion. This shape ensures that the dark-colored litter 40 can be seen as the background to the rainbow in any season. Optimizing the shape of the litter 40 ensures rainbow visibility in all seasons while minimizing the installation area.

[0049] Furthermore, if stone slabs are used as the litter 40, their surfaces may be waterproofed to improve drainage. This prevents sprinkled water from pooling on the litter 40, ensuring a consistently good visibility environment. Furthermore, if dark-colored gravel or crushed stone is used as the litter 40, appropriate surface preparation may be performed to allow water to easily penetrate between these materials. Specifically, a drainage path can be constructed by laying a permeable sheet or sand layer under the gravel or crushed stone, and then providing a base layer with a drainage gradient underneath. This configuration prevents water from pooling on the surface of the litter 40, even after prolonged watering, ensuring consistent rainbow visibility.

[0050] The shielding wall 50 is a wall-like structure installed to function as a background for the rainbow seen by an observer standing on the observation platform 10 and to make the colors of the rainbow stand out more clearly. As shown in FIGS. 2 and 3 , the shielding wall 50 is erected on the far side of the sprinkler space as seen from the observation platform 10. More specifically, the shielding wall 50 is positioned further back than the support 30 to which the high elevation sprinkler system 21 is attached. In this embodiment, the shielding wall 50 is a wall-like structure that rises vertically from the ground surface and is at least partially formed in a dark color. Examples of dark colors include black, dark gray, dark navy blue, dark green, and dark brown. The dark-colored portion of the shielding wall 50 may be within a range that is visible to the observer standing on the observation platform 10 as the background for the rainbow when the observer views the rainbow. In other words, the dark-colored area of ​​the shielding wall 50 may be within a parabola where a triangular pyramid connecting the line of sight and the rainbow intersects with the wall. For example, the height of the dark-colored portion of the shielding wall 50 from the ground surface is preferably about 4 to 10 m, and particularly preferably 5 to 8 m. The width (horizontal length) of the shielding wall 50 is determined taking into consideration the viewing angle from the front of the observation platform 10, and is preferably about 5 to 15 m, for example. This height and width range ensures a dark background in the observer's line of sight even during the winter solstice when the sun's altitude is low. The distance between the shielding wall 50 and the observation platform 10 is determined taking into consideration the position where a rainbow will form and visibility, and is preferably about 10 to 25 m, for example. This distance range can provide an appropriate background for the position where a rainbow will form in each season.

[0051] The shielding wall 50 may be newly constructed as an independent wall-like structure, or the wall surface of an existing building may be utilized. When utilizing the wall surface of an existing building, the wall surface can be made to function as the shielding wall 50 by painting it with an appropriate dark color or by attaching a dark-colored cloth or sheet material to the wall surface. There are no particular restrictions on the material of the shielding wall 50, and the shielding wall 50 may be formed using known materials such as concrete, wood, metal, and resin. It is preferable that the wall surface be painted dark.

[0052] As shown in Figure 2, the shielding wall 50 also serves as a windbreak, protecting the water spraying space from the effects of wind direction and wind speed. In this system installed outdoors, the scattering of water droplets by wind can have a significant impact on the formation of a rainbow. By placing the shielding wall 50 at the back of the water spraying space, it is possible to block wind from the main wind direction and stabilize the distribution of water droplets within the water spraying space. This results in a clearer and more stable rainbow visibility.

[0053] The shielding plantings 60 are natural or artificial plants planted around the periphery of the watering space as viewed from the observation stand 10. The main functions of the shielding plantings 60 are to form a background for the rainbow, similar to the bedding 40 and the shielding wall 50, and to stabilize the distribution of water droplets within the watering space by acting as a windbreak. In particular, in this embodiment, as shown in FIG. 2, the shielding plantings 60 are positioned as far back as the supports 30(a, b) when viewed from the front of the observation stand 10. By locating the shielding plantings 60 around the supports 30(a, b), the supports 30 can be made less noticeable. The shielding plantings 60 may also be installed so as to partially surround the periphery of the space in which the rainbow occurs as viewed from the observation stand 10.

[0054] Also, tall plants such as bamboo and evergreen trees, which are about 3 to 5 meters tall, are used as the shielding planting 60. These plants have dense leaves that tend to form a dark background, and their thin stems and trunks make them less susceptible to wind. In particular, it is advisable to use dark-colored plants as the shielding planting 60. Examples of dark-colored plants include safflower witch hazel, eucalyptus (blacktail), castor bean, crape myrtle black pearl, ficus burgundy, chocolate albizia, heuchera, and raft.

[0055] The motion sensor 70 is a sensor for detecting when an observer steps onto the observation platform 10. As shown in FIG. 2 , the motion sensor 70 is installed on or near the top surface of the observation platform 10. The motion sensor 70 can be a known sensor, such as an infrared sensor, a laser ranging sensor (LRF), a pressure sensor, or an image recognition sensor. In this embodiment, when it detects that an observer has stepped onto the observation platform 10, a control device (not shown) automatically activates the high elevation sprinkler device 21 and the low elevation sprinkler device 22 based on a signal from the motion sensor 70. Furthermore, during periods when the sun is high in the sky, such as summer, the control device also activates the rear sprinkler device 23 in addition to the high elevation sprinkler device 21 and the low elevation sprinkler device 22 based on a signal from the motion sensor 70. This allows water to be sprinkled only when an observer steps onto the observation platform 10, thereby saving water usage and preventing water from being splashed around the surrounding area due to unnecessary sprinkling when the observer is not present.

[0056] The motion sensor 70 may also detect the number of observers and their positions on the observation platform 10. This allows the optimal water sprinkling pattern to be selected by the water sprinkler system 20. For example, when there are multiple observers or when an observer is located in a specific location on the observation platform 10, the operation of the water sprinkler system 20 can be controlled according to the situation. Specifically, it is possible to operate only specific sprinkler devices or adjust the amount and angle of water sprinkling based on the observer's position. This type of control makes it possible to always provide a rainbow under optimal viewing conditions for the observer.

[0057] The rainbow generation system 100 further includes a control device 80 (not shown) for controlling the operation of each component. The control device 80 is an electronic control device installed inside the observation platform 10 or at another appropriate location, and receives detection signals from the motion sensor 70 to control the operation of the sprinkler means 20. The control device 80 is composed of a computer or electronic circuitry including a processor such as a CPU, memory, storage, various interface circuits, etc. The processor of the control device 80 can individually control the operation of each of the sprinkler devices 21, 22, 23 according to a program stored in the memory, etc.

[0058] The control device 80 may calculate the position of the sun based on time information and seasonal information and select the optimal sprinkling pattern. The position of the sun (altitude and azimuth) can be calculated from the geographic location (latitude and longitude), date, and time. Based on this information, the control device 80 may automatically determine which sprinklers should be operated at what intensity and angle to generate the most vivid rainbow for each season and time period. Specifically, the control device 80 may increase the usage rate of the high sprinklers 21 during the winter solstice (when the sun's altitude is low), and increase the usage rate of the low sprinklers 22 and rear sprinklers 23 during the summer solstice (when the sun's altitude is high).

[0059] The operation method of the rainbow generation system 100 according to this embodiment will now be described. This system is primarily intended for installation outdoors, and therefore must be operated in accordance with changes in the position of the sun depending on the season, region, and time of day. First, the recommended basic installation direction for this system is to place the observation stand 10 so that its front faces south. This is because in the Northern Hemisphere, the sun reaches its highest altitude at noon, and this is when the clearest rainbow can be observed. Note that when using this system in the Southern Hemisphere, the observation stand 10 should be placed so that its front faces north.

[0060] Seasonal operation methods must accommodate changes in solar altitude. As shown in Figures 2 and 4, during the winter solstice, when the solar altitude is low, the high-altitude sprinklers 21(a, b) are primarily used to distribute water droplets at the top of the sprinkler space. During this time, rainbows tend to form at approximately the same height as the observer's line of sight. During the vernal and autumnal equinoxes, when the solar altitude is intermediate, the high-altitude sprinklers 21 and low-altitude sprinklers 22 are used in a balanced manner. During this time, rainbows tend to form diagonally below the observer's line of sight. During the summer solstice, when the solar altitude is high, the low-altitude sprinklers 22(a, b) and rear sprinklers 23 are primarily used to distribute water droplets at the bottom of the sprinkler space and at the foot of the observation platform 10. During this time, rainbows tend to form almost directly below the observer's line of sight. Operation methods for different time periods can also accommodate changes in the solar azimuth. In particular, when a movable observation stand 10 is used, it is possible to observe rainbows under optimal conditions throughout the day by changing the orientation of the observation stand 10 depending on the time of day. However, when the observation stand 10 is installed in a fixed position, it is best to keep the observation stand 10 facing south, since the sun is highest at noon (around noon) and rainbows are most visible at this time.

[0061] The rainbow generating system 100 according to the present invention has been described above, focusing on an embodiment in which it is installed outdoors. However, as another embodiment, the system can also be installed indoors to create an exhibition facility where rainbows can be observed at any time. Indoor installation involves installing artificial light sources on the ceiling and walls, covering the floor with dark-colored flooring, and placing an observation platform on top of that. An advantage of indoor installation is that it is not affected by wind or weather, so rainbows can always be generated under stable conditions. Furthermore, since ambient lighting can be controlled indoors, the visibility of the rainbow can be further improved by completely darkening the background.

[0062] In the above description of the present invention, the embodiments of the present invention have been described with reference to the drawings in order to express the contents of the present invention. However, the present invention is not limited to the above embodiments, and includes modifications and improvements that are obvious to those skilled in the art based on the matters described in the present specification. [Explanation of symbols]

[0063] 10...Observation platform 20...Watering means 21...High altitude sprinkler system 22...Low-level sprinkler system 23...Rear sprinkler system 30…post 40…bedding material 50…shielding wall 60…Shielding planting 70...Motion sensor 100...Rainbow generation system

Claims

1. an observation platform having a predetermined height; A rainbow generating system comprising a water sprinkler means, The water sprinkler means includes a first high-altitude water sprinkler device, a second high-altitude water sprinkler device, and at least one low-altitude water sprinkler device, The first elevated water sprinkler device is provided on the left side of the back of the space in front of the observation platform when the observer has his / her back to the light source, as viewed from the observation platform, and sprinkles water toward the space from a nozzle located above the top surface of the observation platform, The second elevated water sprinkler device is provided on the right side of the far side of the space as viewed from the observation platform, and sprinkles water toward the space from a nozzle located above the top surface of the observation platform, The low-altitude sprinkler device is provided on the observation platform and sprinkles water toward the space from a nozzle located below the top surface of the observation platform, As a result, when the light source is positioned above the top surface of the observation platform, a circular rainbow that can be seen by an observer standing on the observation platform is generated in the space. Rainbow generation system.

2. The rainbow generating system further comprises a first support pillar provided on the left side of the far side of the space and a second support pillar provided on the right side of the far side of the space when viewed from the observation platform; The nozzle of the first high elevation sprinkler device is attached to the first support pole, The nozzle of the second high elevation sprinkler device is attached to the second support pole. The rainbow generating system of claim 1 .

3. The first high elevation sprinkler device and the second high elevation sprinkler device spray water sideways or downwards. The rainbow generating system of claim 1 .

4. The low-level sprinkler sprays water upward. The rainbow generating system of claim 1 .

5. The water sprinkler means further includes a rear sprinkler device that sprinkles water toward a space at the feet of the observation stand or toward a space on the rear side of the observation stand when the observer is standing with his / her back to the light source. The rainbow generating system of claim 1 .

6. The water spraying device further includes a dark-colored flooring material installed on the bottom surface of the space to be sprayed with water. The rainbow generating system of claim 1 .

7. The apparatus further includes a shielding wall having a dark-colored portion erected on the far side of the space into which the water sprinkler means sprinkles water as viewed from the observation platform. The rainbow generating system of claim 1 .

8. A rainbow generating method using the rainbow generating system described in claim 1, which sprays water toward the space in front of the observation stand when the observation stand is placed with its back to the light source, thereby generating a circular rainbow that is visible to an observer who has climbed onto the observation stand when the light source is located above the top surface of the observation stand.

Images