Fine bubble generator

Abstract

The inventors have investigated a technology that utilizes a fine bubble generation mechanism that generates fine bubbles by hydraulically feeding and passing water using an AC-powered pump with a pump output of 50 watts or more. However, the inventors realized that such technology poses a risk of electrical leakage due to the use of AC power. Furthermore, the inventors realized that such technology requires the installation of a power supply cable, and that the minimum size of a fine bubble generator to obtain a satisfactory amount of water pressure is usually about half the size of a mandarin orange box, making it often difficult to achieve a compact device. The housing 1100 houses a pump 1300, a battery 1400, and a fine bubble generator 1500, and the housing 1100 is sealed to prevent water 1910 from the water tank 1800 from entering the inside of the housing 1100, forming a fine bubble generator 1000.

Description

[Technical Field]

[0001] The present invention relates to a fine bubble generator that generates fine bubbles in a water tank such as a bathtub. [Background technology]

[0002] A fine bubble generator using a microbubble generator is known, which has a pipe-shaped porous pipe made of a porous body, supplies gas from outside the porous pipe, and generates microbubbles of gas in a liquid flowing through the porous pipe, and at least one of the upstream and downstream ends of the porous pipe is sealed with a packing having an end face pressure-welding portion that does not cover the inner surface of the end but is in pressure contact with the entire end face (see, for example, Patent Document 1).

[0003] This technology is said to be able to provide a microbubble generator that supplies gas from outside a porous pipe to generate microbubbles of gas in a liquid flowing through the porous pipe, and that prevents large bubbles from entering the liquid from the end of the porous pipe.

[0004] Fine bubbles are expected to be used in a variety of fields, including soil purification in the environmental field, promoting the growth of agricultural and livestock products in the agricultural field, preserving freshness in the food field, promoting the growth of marine products in the fishing industry, flushing toilets in the cleaning field, precision peeling in the industrial field, and hot springs such as bubble baths in the beauty field. Needless to say, fine bubbles are also expected to be used in other fields such as medicine and pharmaceuticals. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2017-170278 Summary of the Invention [Problem to be solved by the invention]

[0006] The present inventor believes that it is desirable for fine bubbles, which are expected to have various effects, to be widely used, but has realized that various obstacles must be overcome in order to promote more widespread use of fine bubbles.

[0007] For example, the present inventors have investigated a technology that utilizes a fine bubble generation mechanism that generates fine bubbles by hydraulically feeding in and passing through water using an AC-powered pump with a pump output of 50 watts or more.

[0008] However, the present inventors have noticed that such technology poses a concern about the risk of electrical leakage that accompanies the use of AC power sources.

[0009] The inventors also realized that such technology requires the installation of a power supply cable, and that the minimum size of a fine bubble generator required to obtain a satisfactory amount of water pressure is usually about half the size of a mandarin orange box, making it often difficult to make the device compact.

[0010] The inventors believe that it is extremely important to be able to eliminate the risk of electrical leakage, which reduces safety.

[0011] The present inventors also believe that it is extremely important to reduce the size of the fine bubble generator and make the device compact.

[0012] The present invention takes into consideration the above-mentioned conventional problems and aims to provide a fine bubble generator that can promote more widespread use of fine bubbles. [Means for solving the problem]

[0013] The first aspect of the present invention is a fine bubble generator that is immersed in a water tank, a pipe member having a water inlet and a water outlet; a housing through which the pipe member passes; a pump that circulates water inside the pipe of the pipe member from the water inlet to the water outlet; a battery for supplying power to the pump; a fine bubble generator provided in the pipe member; an irradiator that irradiates the water at a predetermined location inside the pipe with light; an imager that images the water at the predetermined location; It is equipped with The housing accommodates the pump, the battery, and the fine bubble generator, The housing is sealed so that the water in the water tank does not infiltrate into the housing; the housing accommodates the illuminator and the imager; This is a fine bubble generator characterized in that the density of fine bubbles contained in the water is measured by utilizing image analysis of the water imaged by the imager. In the second aspect of the present invention, the water is circulated inside the water tank so that the water flowing out from the water outlet flows in from the water inlet, the illuminator and the imager are disposed near the water inlet; The first fine bubble generator of the present invention is characterized in that when the measured density of the fine bubbles reaches a predetermined level, the power supply to the pump is stopped. A third aspect of the present invention is a method for manufacturing a water-repellent liquid-crystal display device, wherein a pipe wall of the pipe member is provided with an irradiation window through which the irradiator irradiates the light beam and an imaging window through which the imager images the water, the irradiation window portion is disposed so that the direction in which the irradiator irradiates the light beam is a vertical direction; The fine bubble generator of the second invention is characterized in that the imaging window section is arranged so that the direction in which the imaging device images the water is horizontal. The fourth aspect of the present invention is the fine bubble generator according to the third aspect of the present invention, characterized in that the irradiator irradiates the light beam downward. The fifth invention is the fine bubble generator of the fourth invention, characterized in that the bottom of the housing is configured so that the downward irradiated light does not pass through. First invention related to the present invention is a fine bubble generator that is immersed in a water tank, a pipe member having a water inlet and a water outlet; a housing through which the pipe member passes; a pump that circulates water inside the pipe of the pipe member from the water inlet to the water outlet; a battery for supplying power to the pump; a fine bubble generator provided in the pipe member; It is equipped with The housing accommodates the pump, the battery, and the fine bubble generator, This fine bubble generator is characterized in that the housing is sealed to prevent the water in the water tank from entering the inside of the housing.

[0014] Second invention related to the present invention an irradiator that irradiates light onto the water at a predetermined location inside the pipe; an imager that images the water at the predetermined location; It is equipped with the housing accommodates the illuminator and the imager; The density of fine bubbles contained in the water is measured by analyzing the image of the water captured by the image capture device. First invention related to the present invention This is a fine bubble generator.

[0015] Third invention related to the present invention The water is circulated inside the water tank so that the water flowing out from the water outlet flows in from the water inlet, the illuminator and the imager are disposed near the water inlet; When the measured density of the fine bubbles reaches a predetermined level, the power supply to the pump is stopped. Second invention related to the present invention This is a fine bubble generator.

[0016] The fourth invention related to the present invention a pipe wall portion of the pipe member is provided with an irradiation window portion through which the irradiator irradiates the light beam and an imaging window portion through which the imaging device images the water, the irradiation window portion is disposed so that the direction in which the irradiator irradiates the light beam is a vertical direction; The imaging window is disposed so that the direction in which the imaging device images the water is horizontal. Third invention related to the present invention This is a fine bubble generator.

[0017] Fifth Invention Related to the Present Invention The illuminator is characterized in that it irradiates the light beam downward. The fourth invention related to the present invention This is a fine bubble generator.

[0018] The sixth invention related to the present invention The bottom of the housing is configured so that the downward irradiated light does not pass through. Fifth Invention Related to the Present Invention This is a fine bubble generator. [Effects of the Invention]

[0019] The present invention provides a fine bubble generator that can promote wider use of fine bubbles. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is an explanatory diagram of the fine bubble generator according to the present embodiment. [Figure 2] FIG. 2 is an explanatory diagram of the fine bubble generator according to the present embodiment. [Figure 3] 1 is a schematic perspective view of the fine bubble generator of the present embodiment (part 1). [Figure 4] Schematic perspective view of the fine bubble generator of the present embodiment (part 2) [Figure 5] (a) A schematic plan view of the fine bubble generator of this embodiment, (b) A schematic partial side view of the fine bubble generator of this embodiment near the irradiator. [Figure 6] (a) Block diagram of the image analysis device and its vicinity of the fine bubble generator of this embodiment, (b) Perspective view of the pump and its vicinity of the fine bubble generator of this embodiment, (c) Perspective view of the battery and its vicinity of the fine bubble generator of this embodiment. [Figure 7] 1 is a schematic plan view of a fine bubble generator according to a first modified example of the present embodiment; [Figure 8] 1 is a schematic plan view of a fine bubble generator according to a second modified example of the present embodiment. [Figure 9] An explanatory diagram of the irradiator of the fine bubble generator of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to the drawings.

[0022] Similarly, some components may not be shown in the drawings, or may be shown in perspective or in an abbreviated form.

[0023] First, the configuration and operation of the fine bubble generator 1000 of this embodiment will be specifically described with reference to FIGS.

[0024] Here, Figures 1 and 2 are explanatory diagrams (parts 1 and 2) of the fine bubble generator 1000 of this embodiment, Figures 3 and 4 are schematic oblique views (parts 1 and 2) of the fine bubble generator 1000 of this embodiment, and Figure 9 is an explanatory diagram of the irradiator 1600 of the fine bubble generator 1000 of this embodiment.

[0025] In Fig. 4, the housing 1100 is shown perspectively, and wireless communication is indicated by dashed arrows. In Fig. 9, a container of water 1910 that is not bubble-containing purified water is shown on the left, in which light rays 1930 are not visible, although there is some reflection on the glass wall of the container, and a container of water 1910 that is bubble-containing purified water is shown on the right, in which light rays 1930 are clearly visible due to reflection by fine bubbles 1920.

[0026] While explaining the operation of the fine bubble generator 1000 of this embodiment, we will also explain a fine bubble generation method and a fine bubble density measurement method that are inventions related to the present invention.

[0027] The fine bubble generator 1000 is immersed in a water tank 1800.

[0028] To measure the density of fine bubbles 1920 contained in water 1910, as described below, it is not necessarily required that the fine bubble generator 1000 be immersed in the water tank 1800.

[0029] The pipe member 1200 is a unit having a water inlet 1210 and a water outlet 1220 .

[0030] A filter 1 is attached to the water inlet 1210 to prevent impurities from flowing in from the water inlet 1210 along with the water 1910. For example, an auxiliary pipe 2 is attached to the water outlet 1220 to prevent the housing 1100 from vibrating due to the influence of the water flow.

[0031] The housing 1100 is a unit through which a pipe member 1200 passes.

[0032] The housing 1100 is provided with a battery remaining capacity lamp section 11 having four battery remaining capacity lamps, a usage time lamp section 12 having eight usage time lamps each representing 30 minutes of usage time, a function switch 13 and an on / off switch 14, and a chain hanging hole section 15 having a chain hanging hole.

[0033] The pump 1300 is a unit that circulates the water 1910 in the pipe interior 1230 of the pipe member 1200 from the water inlet 1210 to the water outlet 1220 .

[0034] For example, the pump 1300 is a so-called submersible pump, which does not require a suction hose and a circulation return hose.

[0035] The battery 1400 is a unit that supplies power to the pump 1300 .

[0036] For example, battery 1400 is an internal battery with battery specifications of 12.8 volts and 6 amp hours that can provide approximately four hours of underwater device operation without charging.

[0037] The fine bubble generator 1500 is a unit attached to the pipe member 1200.

[0038] For example, the fine bubble generator 1500 is a unit having a cylindrical body that houses the shaft with a predetermined gap between the inner surface of the hollow section and the outer surface of the cylindrical shaft, and a plurality of blades that are provided between the outer surface of the shaft and the inner surface of the cylindrical body and generate turbulence in the fluid flowing through a flow path that is formed to extend spirally from one end of the cylindrical body to the other end, and a plurality of ribs consisting of protrusions that extend in the axial direction of the shaft are provided on the inner surface of the cylindrical body.

[0039] Of course, when generating fine bubbles 1920 by such turbulent activation, if the amount of dissolved oxygen in water 1910 is insufficient, oxygen may be supplementally dissolved into water 1910, for example, by injecting oxygen from an oxygen tank.

[0040] The housing 1100 houses a pump 1300, a battery 1400 and a fine bubble generator 1500.

[0041] Another possible embodiment is to utilize a fine bubble generation mechanism that generates fine bubbles by hydraulically feeding in and passing through water using an AC-powered pump with a pump output of 50 watts or more.

[0042] However, in such an embodiment, there is a concern about the risk of electric leakage that accompanies the use of an AC power source.

[0043] In such an embodiment, a power supply cable must be installed, and the minimum size of the fine bubble generator required to obtain a satisfactory amount of water pressure is usually about half the size of a mandarin orange box, making it often difficult to make the device compact.

[0044] In this embodiment, the pump 1300 is driven by the battery 1400, and no AC power supply is required for the pump 1300, so that the risk of electrical leakage that reduces safety can be eliminated.

[0045] In this embodiment, the housing width X of the housing 1100 is 230 mm, the housing depth Y of the housing 1100 is 65 mm, and the housing height Z of the housing 1100 is 120 mm. In other words, the housing capacity is approximately 2 liters and the two-dimensional size of the housing is A5 size or less, so the size of the fine bubble generator can be reduced and a compact device can be realized.

[0046] The housing 1100 is sealed so that the water 1910 in the water tank 1800 does not enter the inside of the housing 1100 .

[0047] By adopting a charging mechanism for Battery 1400 that incorporates an electromagnetic coupling type charging circuit using a wireless charging coil, which is expected to contribute to making the device more compact, it is possible to operate a submarine-type underwater device in a sealed manner.

[0048] Next, the configuration and operation of the fine bubble generator 1000 of this embodiment will be explained in more detail with reference to Figures 4, 5(a) and 5(b), 6(a), 6(b) and 6(c), and 9.

[0049] Here, Figure 5(a) is a schematic plan view of the fine bubble generator 1000 of this embodiment, Figure 5(b) is a schematic partial side view of the vicinity of the irradiator 1600 of the fine bubble generator 1000 of this embodiment, Figure 6(a) is a block diagram of the vicinity of the image analysis device 30 of the fine bubble generator 1000 of this embodiment, Figure 6(b) is a perspective view of the vicinity of the pump 1300 of the fine bubble generator 1000 of this embodiment, and Figure 6(c) is a perspective view of the vicinity of the battery 1400 of the fine bubble generator 1000 of this embodiment.

[0050] In FIG. 5(a), the direction of the arrow in FIG. 5(b) is indicated by arrow A, wireless communication is indicated by a dashed arrow, and the flow direction of water 1910 is indicated by a hollow arrow.

[0051] The irradiator 1600 is a unit that irradiates the water 1910 at a predetermined location inside the pipe 1230 with a light beam 1930 .

[0052] For example, the illuminator 1600 is a 0.5 watt type laser light illuminator having a relatively small output. The light beam 1930 is a light beam having a wavelength sufficiently small depending on the bubble diameter of the fine bubbles 1920, and may be red light, but is preferably often green or blue light. For example, in terms of laser specifications, visible laser products compliant with the GB7247.1-2012 standard are available with laser output powers of 5 to 30 milliwatts (mW) and emission wavelengths of 510 to 540 nanometers.

[0053] The imager 1700 is a unit that captures an image of water 1910 at a predetermined location.

[0054] For example, the imager 1700 may be a CMOS (Complementary Metal Oxide Semiconductor) camera used in smartphones. The image of the water 1910 may be captured through an optical filter so that the visible light rays 1930 in the image of the water 1910 can be safely viewed without affecting the human body.

[0055] Of the fine bubbles defined as bubbles having a diameter of 100 micrometers or less, not only microbubbles defined as relatively large bubbles having a diameter of 1 micrometer or more, but also ultrafine bubbles defined as relatively small bubbles having a diameter of less than 1 micrometer can be generated.

[0056] However, in such an embodiment, it is difficult to confirm the presence of minute ultrafine bubbles not only with the naked eye, but also with an observation mechanism having a resolution at the microscopic level, and there is a concern that the user will often be unable to convincingly confirm the production of purified water containing significant bubbles.

[0057] In this embodiment, the water 1910, which is bubble-containing purified water, is at least partially transparent, and light rays 1930 that pass through the pipe member 1200 are made visible by being reflected by the fine bubbles 1920, so the user can confirm without any doubt that bubble-containing purified water is being produced.

[0058] The housing 1100 houses the illuminator 1600 and the imager 1700 .

[0059] For measuring the density of fine bubbles 1920 contained in water 1910, as described below, it is not necessarily required that the housing 1100 house the illuminator 1600 and the imager 1700.

[0060] The density of fine bubbles 1920 contained in water 1910 is measured by using image analysis of the water 1910 imaged by imager 1700.

[0061] The visualization of the light rays 1930 and the measurement of the density of the fine bubbles 1920 contained in the water 1910 are performed using the controller 20 housed in the housing 1100, but may also be performed using an image analysis device 30 connected to the controller 20 via wireless communication. The image analysis device 30 is an information processing device such as a smartphone that has a transmitter / receiver 31, an image analysis unit 32, a stop determination unit 33, and an image display unit 34.

[0062] The captured image of the water 1910 is not only displayed on the image display unit 34 but also analyzed by the image analysis unit 32. A simple measurement of the number of fine bubbles 1920 per unit volume is performed by local processing or cloud processing using image analysis software or artificial intelligence analysis technology installed in the image analysis unit 32.

[0063] Next, the configuration and operation of the fine bubble generator 1000 of this embodiment will be described in more detail with reference to FIGS. 5(a), 7, 8, and 9.

[0064] 7 and 8 are schematic plan views of the fine bubble generator 1000 according to first and second modified examples of the present embodiment.

[0065] In FIGS. 7 and 8, wireless communication is indicated by dashed arrows, and the flow direction of water 1910 is indicated by hollow arrows.

[0066] Water 1910 is circulated inside the water tank 1800 so that water 1910 flowing out from the water outlet 1220 flows in from the water inlet 1210 .

[0067] The water 1910 may be moved, for example, from the water storage section to the water use section through a connection in which at least the fine bubble generator 1500 is located, without being circulated inside the water tank 1800.

[0068] The illuminator 1600 and the imager 1700 are positioned near the water inlet 1210 .

[0069] The illuminator 1600 and the imager 1700 may be disposed near the water outlet 1220. More specifically, the pump 1300 may be disposed near the water outlet 1220, and the illuminator 1600 and the imager 1700 may be disposed upstream or downstream of the pump 1300. However, the density of the fine bubbles 1920 near the water inlet 1210 is expected to best represent the density of the fine bubbles 1920 that will eventually become approximately uniform inside the water tank 1800 as sufficient water 1910 circulates.

[0070] When the measured density of the fine bubbles 1920 reaches a predetermined level, the power supply to the pump 1300 is stopped.

[0071] The density of the fine bubbles 1920 contained in the water 1910 increases as the pump 1300 operates, but the increase in the density of the fine bubbles 1920 almost stops when a saturated state is reached, and the density of the fine bubbles 1920 may begin to decrease.

[0072] The pump 1300 is remotely monitored by using smartphone communication via the transmitter / receiver 31. The pump 1300 is stopped in response to a stop determination made by the stop determination unit 33, so that power consumption of the battery 1400 can be saved.

[0073] The pipe wall 1240 of the pipe member 1200 is provided with an irradiation window 1241 through which the irradiator 1600 irradiates the light beam 1930 and an imaging window 1242 through which the imager 1700 captures an image of the water 1910 .

[0074] The irradiation window portion 1241 may have two windows, such as an entrance window and an exit window, arranged to face each other so that the light ray 1930 passes through the pipe member 1200 without being reflected. The imaging window portion 1242 may have two windows, such as a first and a second imaging window, so that an imaging direction, such as upward or downward, can be selected. Needless to say, almost the entire pipe wall portion 1240 may be formed of transparent glass, and the irradiation window portion 1241 and the imaging window portion 1242 may be integrally configured as a single window.

[0075] The irradiation window portion 1241 is disposed so that the direction in which the irradiator 1600 irradiates the light beam 1930 is vertical.

[0076] The direction in which the irradiator 1600 irradiates the light beam 1930 does not necessarily have to be vertical. However, even when the housing 1100 is opened for equipment maintenance work, a user performing equipment maintenance work beside the fine bubble generator 1000 is unlikely to inadvertently look directly at the light beam 1930 irradiated in the vertical direction, and therefore improved safety can often be expected.

[0077] The imaging window section 1242 is arranged so that the direction in which the imager 1700 captures the image of the water 1910 is horizontal.

[0078] Since the imaging direction of the imager 1700 is perpendicular to the irradiation direction of the irradiator 1600, high image quality of the image of water 1910 obtained by imaging is guaranteed, and high accuracy of the density of fine bubbles 1920 measured using image analysis is expected.

[0079] Illuminator 1600 emits a beam of light 1930 downward.

[0080] The irradiator 1600 may irradiate the light beam 1930 upward. However, a user performing equipment maintenance work beside the fine bubble generator 1000 may occasionally look down at the fine bubble generator 1000, but rarely looks up at the fine bubble generator 1000, and is unlikely to inadvertently look directly at the light beam 1930 irradiated downward.

[0081] The bottom of the housing 1100 is configured to prevent downwardly projected light beam 1930 from passing through.

[0082] Because light ray 1930 does not pass through and exit from the bottom of housing 1100 to the outside of housing 1100, there is almost no chance that a user will inadvertently look directly at light ray 1930. Needless to say, for example, the bottom portion of housing 1100 onto which light ray 1930 is irradiated may be made of a material that does not allow light ray 1930 to pass through, and other portions may be made of a transparent material.

[0083] The program of the invention related to the present invention is a program that causes a computer to execute all or some of the steps (or processes, operations, actions, etc.) of the fine bubble generation method and fine bubble density measurement method of the invention related to the present invention described above, and is a program that operates in cooperation with a computer.

[0084] In addition, the recording medium of the invention related to the present invention is a recording medium on which a program is recorded for causing a computer to execute all or some of the operations of all or some of the steps (or processes, actions and functions, etc.) of the fine bubble generation method and fine bubble density measurement method of the invention related to the present invention described above, and is a computer-readable recording medium in which the read program is used in cooperation with a computer.

[0085] It should be noted that the above-mentioned "some steps (or processes, operations, actions, etc.)" means one or some of the multiple steps.

[0086] Furthermore, the above-mentioned "operations of steps (or processes, operations, actions, etc.)" means the operations of all or part of the above-mentioned steps.

[0087] Furthermore, one mode of use of the inventive program related to the present invention may be in the form of being transmitted through a transmission medium such as the Internet, light, radio waves, or sound waves, being read by a computer, and operating in cooperation with the computer.

[0088] The recording medium also includes a ROM (Read Only Memory).

[0089] Furthermore, a computer is not limited to pure hardware such as a CPU (Central Processing Unit), and may also include firmware, an OS (Operating System), and even peripheral devices.

[0090] As described above, the configuration of the present invention may be realized in software or hardware. [Industrial Applicability]

[0091] The fine bubble generator of the present invention can promote the wider use of fine bubbles and is useful for use as a fine bubble generator that generates fine bubbles in aquariums such as bathtubs. [Explanation of symbols]

[0092] 1 filter 2 auxiliary pipes 11 Battery remaining capacity lamp 12 Usage time lamp section 13 Function switch 14 On / Off Switch 15 Chain hanging hole 20 Controller 30 Image analysis equipment 31 Transmitter / Receiver 32 Image analysis unit 33 Stop judgment section 34 Image display unit 1000 Fine Bubble Generator 1100 cabinet 1200 Pipe members 1210 Water inlet 1220 Water outlet 1230 Inside the pipe 1240 Pipe wall 1241 Irradiation window part 1242 Imaging window section 1300 Pump 1400 battery 1500 Fine Bubble Generator 1600 Irradiator 1700 Imager 1800 aquarium 1910 water 1920 Fine Bubbles 1930 Ray of light A arrow X chassis width Y Housing depth Z chassis height

Claims

1. A fine bubble generator that is submerged in a water tank, A pipe member having a water inlet and a water outlet; a housing through which the pipe member penetrates; a pump that circulates water inside the pipe of the pipe member from the water inlet to the water outlet; a battery for supplying power to the pump; A fine bubble generator provided in the pipe member; an irradiator that irradiates light onto the water at a predetermined location inside the pipe; an imager for imaging the water at the predetermined location; Equipped with The housing accommodates the pump, the battery, and the fine bubble generator, The housing is sealed so that the water in the water tank does not enter the inside of the housing; The housing houses the illuminator and the imager, A fine bubble generator characterized in that the density of fine bubbles contained in the water is measured by utilizing image analysis of the water imaged by the imager.

2. The water is circulated inside the water tank so that the water flowing out from the water outlet flows in from the water inlet, The illuminator and the imager are disposed near the water inlet, The fine bubble generator as described in claim 1, characterized in that the power supply to the pump is stopped when the measured density of the fine bubbles reaches a predetermined level.

3. a pipe wall portion of the pipe member is provided with an irradiation window portion through which the irradiator irradiates the light beam and an imaging window portion through which the imaging device images the water, The irradiation window portion is disposed so that the direction in which the irradiator irradiates the light beam is a vertical direction, The fine bubble generator according to claim 2, wherein the imaging window portion is disposed so that the direction in which the imaging device images the water is horizontal.

4. The fine bubble generator according to claim 3, wherein the irradiator irradiates the light beam downward.

5. The fine bubble generator according to claim 4, characterized in that the bottom of the housing is configured so that the downwardly irradiated light does not pass through.

Images