Illumination device and cultivation system

Abstract

To control the output of light suitable for plant growth by using a white light source.SOLUTION: A growth system utilizing natural light includes a greenhouse and a plurality of lighting devices disposed above plants to be grown in the greenhouse. The growth system includes a plurality of white light sources, a plurality of auxiliary light sources each of which is configured to emit red light and far-red light, and an illumination controller configured to control a degree of emission of light from the white light sources or the auxiliary light sources through the plurality of lighting devices. The illumination controller is configured to start or stop the control of light emission from the white light sources or the auxiliary light sources according to sunrise or sunset.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an illumination device and a cultivation system. [Background technology]

[0002] Conventionally, there have been known methods of growing plants such as fruits, vegetables, and flowers by artificially illuminating them with light. Methods of using artificial light in such plant growth include combining it with natural light from the sun, and using only artificial light in an indoor space that is shielded from sunlight and the outside air.

[0003] When sunlight is utilized, artificial light is often used as a supplementary light. For example, artificial light is used to supplement the lack of daylight hours during seasons when the hours of daylight are short, or to supplement the amount of light that is less than on a sunny day due to cloudy or rainy weather. Patent Document 1 discloses a system that controls the output of blue and far-red light sources according to the amount of light from a light source such as natural light. LEDs (light-emitting diodes) are used as the supplementary blue and far-red light sources. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2018-509921 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Document 1 does not disclose a system for controlling the output of a white light source, nor does it discuss a suitable system in which a white light source is combined with a red light source or a far-red light source. [Means for solving the problem]

[0006] The lighting device of the present invention has a white light source, an auxiliary light source that irradiates red light and far-red light, and an illumination control unit that controls the degree of light irradiation by the white light source or the auxiliary light source, and the illumination control unit starts or ends control of light irradiation by the white light source or the auxiliary light source in accordance with sunrise or sunset.

[0007] In addition, the lighting device according to the present invention is an lighting device that includes a white light source, an auxiliary light source that irradiates red light and far-red light, and an illumination control unit that controls the degree of light irradiation by the white light source or the auxiliary light source, and the illumination control unit controls the light irradiation by the white light source or the auxiliary light source according to one weather classification identified from a plurality of weather classifications.

[0008] In addition, the present invention relates to a cultivation system having a greenhouse and a plurality of lighting devices provided above plants to be cultivated within the greenhouse. The cultivation system has a plurality of white light sources, a plurality of auxiliary light sources that irradiate red light and far-red light, and an illumination control unit that controls the degree of light irradiation by the white light sources or the auxiliary light sources from the plurality of lighting devices, and the illumination control unit starts or ends control of light irradiation by the white light sources or the auxiliary light sources in accordance with sunrise or sunset.

[0009] In addition, the present invention relates to a cultivation system having a greenhouse and a plurality of lighting devices arranged above plants to be cultivated within the greenhouse, the cultivation system having a plurality of white light sources, a plurality of auxiliary light sources that irradiate red light and far-red light, and an illumination control unit that controls the degree of light irradiation by the white light sources or the auxiliary light sources from the plurality of lighting devices, and the illumination control unit controls the irradiation of light by the white light sources or the auxiliary light sources according to one weather classification identified from a plurality of weather classifications. Effect of the Invention

[0010] According to one embodiment of the present invention, a white light source can be used to control the output of light suitable for plant growth. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic perspective view of an illumination device according to a first embodiment. [Diagram 2] FIG. 2 is a top view of the illumination device according to the first embodiment. [Diagram 3] FIG. 3 is a diagram illustrating an example of a hardware configuration of the illumination device according to the first embodiment. [Figure 4] FIG. 4 is a diagram illustrating another example of the hardware configuration of the illumination device according to the first embodiment. [Diagram 5] FIG. 5 is a schematic diagram of a plant cultivation system. [Figure 6] FIG. 6 is a diagram showing functional blocks of an illumination device according to the second embodiment. [Figure 7] FIG. 7 is a diagram showing functional blocks of an illumination device according to the third embodiment. [Figure 8] FIG. 8 is a schematic diagram showing the positional relationship between the light quantity measuring unit of the illumination device and the sun. [Figure 9] FIG. 9 is a diagram illustrating an example of the data structure of the correction data stored in the correction data storage unit. [Figure 10] FIG. 10 is a diagram showing a system configuration of the development system according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The embodiments for carrying out the present invention will be described below with reference to the drawings. However, the embodiments described below are intended to embody the technical ideas of the present invention and are not intended to limit the present invention. Furthermore, in the following description, the same names and symbols indicate the same or similar components, and detailed description will be omitted as appropriate. Note that the sizes and positional relationships of the components shown in each drawing may be exaggerated for clarity of explanation. Furthermore, the relationship between color names and chromaticity coordinates, the relationship between the wavelength range of light and the color names of monochromatic light, etc., follow JIS Z8110.

[0013] First, we will explain plant growth. Plants' responses to light can be divided into photosynthesis and photomorphogenesis. Photosynthesis is a reaction that uses light energy to synthesize organic matter. On the other hand, photomorphogenesis is a morphological reaction that uses light as a signal, and is a reaction that performs seed germination, differentiation (germination formation, leaf formation, etc.), movement (stoma opening and closing, chloroplast movement), phototropism, etc. Plants have multiple photoreceptors (pigments), and chlorophyll and carotenoids carry out photosynthesis.

[0014] In addition to chlorophyll and carotenoids, plants also have photoreceptors (pigments), such as phytochromes, which are photoreceptors for red and far-red light, and cryptochromes and phototropins, which are photoreceptors for blue light and near ultraviolet light (UV-A). For example, phytochromes absorb red and far-red light and promote the photomorphogenesis of plants, such as the induction of seed germination, the development of cotyledons, the elongation of stems, and phototropism.

[0015] Plants use photoreceptors to sense the light environment and initiate photosynthetic and photomorphogenic reactions. The wavelength range (300nm to 800nm) that plants can use for photosynthesis and photomorphogenesis is almost the same as the wavelength range of visible light (380nm to 780nm), and in the field of plants, radiation in the wavelength range that can be used for photosynthetic and photomorphogenic reactions is called physiologically active radiation. Among these, radiation in the wavelength range of 400nm to 700nm, which is the energy source for plant growth, is called photosynthetically active radiation.

[0016] In the field of plants, the wavelength range from about 400 nm to about 500 nm is sometimes expressed as blue light B, the wavelength range from about 500 nm to about 600 nm as green light G, the wavelength range from about 600 nm to about 700 nm as red light R, and the wavelength range from about 700 nm to about 800 nm as far-red light Fr. Also, the indicator of the amount of light effective for photosynthesis and photomorphogenesis is expressed not in radiant flux but in photon flux or photon flux density. Photon flux density (μmol m-2 ·s -1 ) is the number of photons reaching a unit area per unit time. Photon flux (μmol s -1 ) is the number of light quanta per unit time.

[0017] The spectral distribution of a light source that affects plant growth varies depending on the ratio R / B or R / Fr of the photon flux in a specific wavelength range to the photon flux in another specific wavelength range. For example, in "Shirai Kana et al., Plant Growth Effects of White LEDs with Different Spectral Distributions, Abstracts of the 2016 Kanazawa Conference of the Japanese Society of Bioenvironmental Engineering, Japan, pp. 40 and 41," it is described that differences in the spectral distribution of light sources affect the height of romaine lettuce, for example, and that the smaller the R / Fr, the taller the romaine lettuce will be.

[0018] First Embodiment FIG. 1 shows a schematic perspective view of an illumination device 10 according to the first embodiment. FIG. 2 shows a schematic top view of the illumination device 10. The illumination device 10 has a plurality of white light sources 110, a plurality of auxiliary light sources 111, a first solar panel 132 functioning as an illumination detector, and a second solar panel 133 functioning as a light quantity measuring unit 113. In addition, one row by M columns (M is 1 or more) of auxiliary light sources 111 are arranged between the rows of the white light sources 110 arranged in two rows by N columns (N is 1 or more), and two sets of white light and auxiliary light sources 111 arranged in three rows are arranged in total. Note that the arrangement of the white light sources and auxiliary light sources is not limited to this. For example, the white light sources and the auxiliary light sources may be arranged alternately in each row, or other arrangement methods may be used.

[0019] The white light source 110 in the illumination device 10 is configured to include a plurality of white light emitting devices 130. For example, a white LED can be adopted as the white light emitting device 130. The white LED can be realized by appropriately combining a light emitting element having an emission peak in the purple to blue range with a phosphor that emits blue, green, yellow, orange, red, far red, or the like by the light from the light emitting element.

[0020] The auxiliary light source 111 in the illumination device 10 is configured to have a plurality of auxiliary light-emitting devices 131. The auxiliary light-emitting devices 131 employ a light-emitting device in which the ratio R / B of the photon flux R of red light in a wavelength range of 620 nm or more and less than 700 nm to the photon flux B of blue light in a wavelength range of 400 nm or more and 490 nm or less is greater than 4 and is 50 or less, and the ratio R / Fr of the above-mentioned photon flux R to the photon flux Fr of far-red light in a wavelength range of 700 nm or more and 780 nm or less is 0.1 or more and 10 or less.

[0021] Such a light emitting device can be realized, for example, by a light emitting element having an emission peak wavelength within a wavelength range of 380 nm or more and 490 nm or less (hereinafter sometimes referred to as the "near ultraviolet to blue region"), a first phosphor that is excited by light from the light emitting element and emits light having at least one emission peak wavelength within a wavelength range of 580 nm or more and less than 680 nm, and a second phosphor that is excited by light from the light emitting element and emits light having at least one emission peak wavelength within a wavelength range of 680 nm or more and 800 nm or less.

[0022] The first phosphor is Mn 4+ Activated fluorogermanate phosphor, Eu 2+ Activated nitride phosphor, Eu 2+ Activated alkaline earth sulfide phosphor and Mn 4+ Activated halide phosphors, etc. The first phosphor may be one selected from these phosphors, or two or more of them may be used in combination.

[0023] The second phosphor is at least one phosphor selected from the group consisting of a first aluminate phosphor having a composition containing Al and Cr, and a second aluminate phosphor having a composition containing a first element Ln containing at least one element selected from the group consisting of rare earth elements excluding Ce, Al, and optionally a second element M containing at least one element selected from the group consisting of Ga and In, Ce, and Cr, wherein when the total molar composition ratio of Al and the second element M is 5, the molar composition ratio of Ce is the product of the variable x and 3, the molar composition ratio of Cr is the product of the variable y and 3, the variable x is a number greater than 0.0002 and less than 0.50, and the variable y is a number greater than 0.0001 and less than 0.05.

[0024] Furthermore, a light emitting device in which R / B, which indicates the ratio of photon flux R in the range of 620 nm to less than 700 nm to photon flux B in the range of 380 nm to 490 nm, is 2.0 to 4.0, and R / FR, which indicates the ratio of photon flux R in the range of 620 nm to less than 700 nm to photon flux FR in the range of 700 nm to 780 nm, is 0.7 to 13.0, may be used for the auxiliary light emitting device 131. When distinguishing from the above-mentioned light emitting devices, they are referred to as the first light emitting device 140 and the second light emitting device 141, respectively.

[0025] The second light emitting device 141 can be realized by, for example, a light emitting element having an emission peak wavelength in the near ultraviolet to blue region, a first phosphor excited by the light from the light emitting element to emit light having at least one emission peak wavelength in the range of 580 nm to less than 680 nm, and a second phosphor excited by the light from the light emitting element to emit light having one or more emission peak wavelengths in the range of 680 nm to 800 nm. As the first phosphor, a phosphor similar to that of the first light emitting device 140 described above can be used.

[0026] The second phosphor is a phosphor having an aluminate composition comprising a first element Ln containing at least one element selected from the group consisting of rare earth elements excluding Ce, a second element M containing at least one element selected from the group consisting of Al, Ga and In, Ce and Cr, wherein when the molar composition ratio of the second element M is 5, the molar composition ratio of Ce is the product of x and 3, and the molar composition ratio of Cr is the product of y and 3, wherein the x is a number greater than 0.0002 and less than 0.50, and the y is a number greater than 0.0001 and less than 0.05.

[0027] Furthermore, the auxiliary light-emitting device 131 may be a light-emitting device in which the ratio R / B of the photon flux R of red light in the range of 620 nm or more and 700 nm or less to the photon flux B of blue light in the range of 400 nm or more and 490 nm or less is more than 20 and is not more than 200. When distinguishing this from the first light-emitting device 140 and the second light-emitting device 141 described above, this will be referred to as a third light-emitting device 142.

[0028] The third light-emitting device 142 can be realized by a light-emitting element having an emission peak wavelength in the near-ultraviolet to blue region, and a red phosphor that is excited by light from the light-emitting element to emit light having at least one emission peak wavelength in the range of 580 nm or more and 680 nm or less.

[0029] The red phosphor is Eu 2+ Activated nitride phosphor, Mn 4+ Activated fluorogermanate phosphor, Eu 2+ Activated alkaline earth sulfide phosphor and Mn 4+ Activated halide phosphors, etc. The red phosphor may be one selected from these phosphors, or two or more of them may be used in combination.

[0030] The auxiliary light source 111 may be a combination of a plurality of light emitting devices appropriately selected from the first light emitting device 140, the second light emitting device 141, and the third light emitting device 142 as the plurality of auxiliary light emitting devices 131. Alternatively, another light emitting device, for example, a light emitting device using a red LED without phosphor or a light emitting device using a far-infrared LED may be used.

[0031] The first light-emitting device 140 and the second light-emitting device 141 emit light in the red and far-infrared regions. The first light-emitting device 140 has a larger R / B than the second light-emitting device 141. In other words, the first light-emitting device 140 emits less blue light. For example, when using natural light such as the white light source 110 or sunlight together, and there is no need to supplement blue light with the auxiliary light source 111, the first light-emitting device 140 can be selected.

[0032] The third light-emitting device 142 can enhance red light emission while emitting relatively less far-infrared light compared to the first light-emitting device 140 and the second light-emitting device 141. When it is desired to enhance supplementary light by red light rather than far-infrared light, the third light-emitting device 142 can be selected. For example, by using the auxiliary light source 111 in which a light-emitting device that emits red light but does not emit far-red light, such as the third light-emitting device 142, and a light-emitting device that emits red and far-red light, such as the first light-emitting device 140 or the second light-emitting device 141, are arranged, it is possible to supplement red and far-red light in a balanced manner in addition to natural light and white light. It should be noted that not emitting far-red light is not limited to meaning that it is not emitting at all, but also includes a state in which it is hardly emitting at all.

[0033] The first solar panel 132 and the second solar panel 133 have solar cells and convert light energy from the sun into electricity. The first solar panel 132 is provided on each side of the illumination device 10, and a plurality of first solar panels 132 are attached to the illumination device 10. A rise / fall detection unit 112 that detects the rise / fall of the sun is realized based on the value of the power converted by the first solar panel 132. The second solar panel 133 is provided on the upper surface of the illumination device 10, and one or more second solar panels 133 are attached to the illumination device 10. A light quantity measurement unit 113 that measures the quantity of light emitted by natural light such as sunlight, independent of the illumination device 10, is realized based on the value of the power converted by the second solar panel 133.

[0034] 3 is a diagram showing an example of a hardware configuration of the illumination device 10. The illumination device 10 includes a power supply unit 116, an illumination control switch 114, and a white control switch 115 in addition to the above-mentioned multiple white light sources 110 and auxiliary light sources 111, the elevation detection unit 112, and the light quantity measurement unit 113. The power supply unit 116 supplies power for performing supplementary lighting by the white light source 110 and the auxiliary light source 111. The illumination control switch 114 controls the ON / OFF of the power supply to control supplementary lighting by the white light source 110 and the auxiliary light source 111. The white control switch 115 also controls supplementary lighting by the white light source 110. Note that when the illumination control switch 114 is OFF, the white light source 110 does not emit light even if the white control switch 115 is ON. Also, even if the illumination control switch 114 is ON, when the white control switch 115 is OFF, the white light source 110 does not emit light.

[0035] Fig. 4 is a diagram showing another example of the hardware configuration of the illumination device 10. Similar to Fig. 3, the illumination device 10 includes a plurality of white light sources 110 and auxiliary light sources 111, a lifting / lowering detection unit 112, a light quantity measurement unit 113, a power supply unit 116, an illumination control switch 114, and a white control switch 115. For convenience, the plurality of white light sources 110 and the auxiliary light sources 111 are each shown in a single block diagram. In the example of Fig. 4, the illumination device 10 further includes a communication I / F 121, a ROM 118 (Read Only Memory), a RAM 119 (Random Access Memory), a CPU 117 (Central Processing Unit), and a HDD 120 (Hard Disk Drive). Each of these pieces of hardware is connected to each other via a bus.

[0036] The communication I / F 121 is an interface for connecting to a network. The HDD 120 is a non-volatile storage device that stores programs and data. The ROM 118 is a non-volatile semiconductor memory that can retain programs and data even when the power is turned off. The RAM 119 is a volatile semiconductor memory that temporarily retains programs and data. The CPU 117 is a calculation device that reads programs and data from storage devices such as the ROM 118 and the HDD 120 onto the RAM 119 and executes processing to realize the control and functions of the entire illumination device 10.

[0037] 4, the light emission control of the white light source 110 and the auxiliary light source 111 in the illumination device 10 is controlled by the CPU 117. Specifically, the CPU 117 obtains the power values ​​obtained by the first solar panel 132 and the second solar panel 133, and determines whether to turn the illumination control switch 114 and the white control switch 115 ON or OFF based on the power values, and controls them.

[0038] 5 shows a system configuration diagram of a cultivation system 1 having an illumination device 10. In the cultivation system 1, a plurality of illumination devices 10 are installed on the ceiling of a greenhouse 20. Each illumination device 10 is connected to wiring also stretched on the ceiling and receives a supply of electricity. In addition, the ceiling and sides of the greenhouse 20 are covered with translucent glass, vinyl, or the like, so that light from the sun can reach the inside of the greenhouse 20.

[0039] In the cultivation system 1, a translucent greenhouse 20 is used to capture as much natural light as possible, such as sunlight. However, in areas where natural light, such as sunlight, is strong, such as countries directly on the equator, if natural light is directly captured, the light may be too strong and prevent plants from growing. In such cases, the cultivation system 1 having multiple illumination devices 10 may be constructed in a greenhouse 20 with a deliberately lowered transmittance. For example, it may be possible to use a greenhouse 20 with a transmittance of about 60% to 80% in the R, G, B, and Fr wavelength regions.

[0040] Next, the operation of the illumination device 10 in the cultivation system 1 in which the illumination device 10 is installed in the greenhouse 20 will be described. The illumination control switch 114 is switched OFF when power equal to or greater than a predetermined value is not obtained from any of the multiple first solar panels 132, thereby stopping illumination by the white light source 110 and the auxiliary light source 111. In addition, while power is being supplied from the power supply unit 116 and power equal to or greater than a predetermined value is being obtained from any of the multiple first solar panels 132, the switch is maintained in the ON state.

[0041] This predetermined value is set to be a first threshold value that distinguishes between a state where the sun has set and it is night and a state where it is not. In other words, it is desirable to set this first threshold value so that the power obtained is equal to or greater than the predetermined value during the period from when the sun rises above the horizon and becomes bright until the sun sets, regardless of whether the weather is sunny, cloudy, or rainy. However, it is not necessary to strictly define the boundary between night and other states and set the first threshold value. The first threshold value should be sufficient as long as it can control the illumination by the white light source 110 and the auxiliary light source 111 approximately in accordance with the rise and fall of the sun, even if there is a slight time lag.

[0042] Furthermore, the first solar panels 132 are disposed on each side of the illumination device 10, allowing for freedom of arrangement when determining the orientation of the illumination device 10 in accordance with the rise and fall of the sun. Since light from the white light source 110 and the auxiliary light source 111 is radiated toward the plants, the white light source 110 and the auxiliary light source 111 face toward the ground. Furthermore, the orientation of the illumination devices 10 when they are arranged will be adjusted according to the arrangement of the plants. Therefore, a detection area for measuring the irradiance of light is provided on each side of the illumination device 10 so that the rise and fall of the sun can be detected appropriately.

[0043] However, it is not necessarily provided on all side surfaces. The rise / fall detection unit 112 in the illumination device 10 according to the first embodiment has at least a first detection area for detecting sunrise and a second detection area for detecting sunset. As a specific example, a first solar panel 132 is provided on each of the opposing side surfaces. The first solar panel 132 may be physically separate, or may be composed of a single solar panel.

[0044] The rise and fall detection unit 112 allows supplemental lighting by the illumination device 10 to operate in response to the rise and fall of the sun. In other words, when the sun rises, a state in which no power equal to or greater than the first threshold value is obtained from any of the first solar panels 132 changes to a state in which the power obtained from at least the first solar panels 132 in the first detection area is equal to or greater than the first threshold value. As a result, when the sun rises, the illumination control switch 114 turns ON, and supplemental lighting by the white light source 110 and the auxiliary light source 111 begins.

[0045] After that, the sun moves, but as long as the surroundings do not become as dark as night, any of the first solar panels 132 among the multiple first solar panels 132 obtains power equal to or greater than the first threshold, and the illumination control switch 114 is maintained in the ON state. Then, when the sun sets, the first solar panel 132 in the second detection area obtains more power than the other first solar panels 132, but as the sun sets, the power of the first solar panel 132 in the second detection area becomes less than the first threshold. At this time, the power obtained from all the first solar panels 132 inevitably becomes less than the first threshold, so the illumination control switch 114 is turned OFF, and supplementary lighting by the white light source 110 and the auxiliary light source 111 ends until the next morning.

[0046] The side surface of the illumination device 10 is inclined upward, that is, inward from the position where it intersects with the light emitting surface on which the white light source 110 and the like are arranged and provides illumination, toward the direction in which the second solar panel 133 is arranged. This is to take into consideration the influence of light from the white light source 110 and the auxiliary light source 111 in the power conversion by the first solar panel 132. In other words, if power above a predetermined value is obtained from the light from the white light source 110 and the auxiliary light source 111 even after the sun has set, the control to turn off the illumination control switch 114 in response to sunset will no longer work.

[0047] However, if the first threshold value is set by correcting (correcting upward) the influence of light from the white light source 110 and the auxiliary light source 111, a situation may occur where the light does not turn on even when the sun rises. Also, a method such as adding a light shielding plate to block the light from the white light source 110 and the auxiliary light source 111 would prevent the use of natural light such as the sun. For this reason, a slope is provided as a structure that prevents the power obtained from the first solar panel 132 from being influenced by the light from the white light source 110 and the auxiliary light source 111 as much as possible, and yet does not interfere with irradiation by natural light. However, the slope is not necessarily provided, and can be achieved by other methods such as correction.

[0048] When the power converted by the second solar panel 133 is equal to or greater than a predetermined value, the white light control switch 115 is switched off and the power supply to the white light source 110 is stopped. As a result, the white light source 110 stops emitting light and the auxiliary light source 111 continues to provide supplementary light. This makes it possible to control the white light source 110 to stop illuminating the plant when the plant is being irradiated with sufficient natural light, such as from the sun.

[0049] Suppressing excessive illumination caused by supplementary lighting from the white light source 110 not only provides a good growing environment but also leads to energy savings. The predetermined value for the second solar panel 133 is preferably set to a second threshold value that is the lower limit at which it is determined that sufficient light is reaching the plant. This value may vary depending on the type of plant being grown, so it is preferably set based on the appropriate amount of white light that promotes the growth of the plant. At least the second threshold value is higher than the first threshold value. Note that by arranging the second solar panel 133 facing upward, it is possible to control excessive illumination during the daytime when the irradiance of sunlight is generally strong.

[0050] Next, when the power converted by the second solar panel 133 falls below a predetermined value, the white control switch 115 turns ON and the white light source 110 resumes emitting light. However, when the illumination control switch 114 is OFF, the white light source 110 does not emit light. As a result, the ON / OFF of supplementary light by the white light source 110 is controlled during daylight hours, but after sunset, the white light source 110 does not emit light until the illumination control switch 114 turns ON at sunrise.

[0051] It is not necessary to stop the supplementary light from all the white light sources 110 by the white control switch 115. For example, the supplementary light from some of the white light sources 110 may be stopped, or the emission of light from some of the white light emitting devices 130 may be stopped. Also, instead of stopping, a process of weakening or strengthening the intensity may be performed. In other words, the degree of irradiation of light from the white light source 110 may be strengthened to compensate for the weakened light from natural light, and weakened to remove the excess light if the light from natural light becomes strong. The light quantity measurement unit 113 may be composed of one second solar panel 133 or may be composed of multiple second solar panels 133.

[0052] In this way, the illumination device 10 in the cultivation system 1 according to the first embodiment has an illumination control means for controlling supplementary lighting (degree of light irradiation) by the white light source 110 and the auxiliary light source 111 in accordance with the rising and setting of the sun. Also, it has an illumination control means for controlling supplementary lighting by the white light source 110 in accordance with the irradiance (degree of illumination) of light from natural light. This makes it possible to dynamically control the start and end of supplementary lighting (irradiation control) by the white light source 110 or the auxiliary light source 111 in accordance with the daily cycle from sunrise to sunset.

[0053] The elevation detection unit 112 provides an elevation parameter corresponding to the irradiance, and the illumination control unit controls supplemental light based on the elevation parameter and a first threshold value. The light quantity measurement unit 113 provides a light quantity parameter corresponding to the irradiance, and the illumination control unit controls supplemental light based on the light quantity parameter and a second threshold value.

[0054] The ascent and descent parameters provided by the ascent and descent detection unit 112 are not limited to sunrise and sunset, and are designed to have high detection sensitivity at sunrise and sunset. The light quantity parameters provided by the light quantity measurement unit 113 are not limited to sunrise and sunset, and are designed to have higher measurement sensitivity at noon (when the sun is at its highest) than at sunrise and sunset.

[0055] <Second embodiment> Fig. 6 is a functional block diagram showing functions of the illumination device 11 in the cultivation system 1 according to the second embodiment. Various functions and processes described with reference to Fig. 6 are realized by the operation of a CPU 117 in the illumination device 11 having the hardware configuration shown in Fig. 4, for example. Therefore, the hardware configuration of the illumination device 11 according to the second embodiment may be similar to that of the illumination device 10 of the first embodiment.

[0056] The cultivation system 1 of the second embodiment, in addition to controlling the ON / OFF of supplementary lighting in accordance with the rise and fall of the sun as described in the first embodiment, also provides a mechanism for irradiating light to plants for a period of time longer than the sun's daylight hours.

[0057] The rise / fall determination unit 250 determines whether the sun rises or falls based on the rise / fall parameters obtained by the rise / fall detection unit 112. The illuminance determination unit 251 determines the degree of illumination based on the light intensity parameters obtained by the light intensity measurement unit 113. The illumination control unit 252 controls whether or not to perform supplemental lighting using the white light source 110 and the auxiliary light source 111 based on the result of the determination by the rise / fall determination unit 250. Also, controls whether or not to perform supplemental lighting using the white light source 110 based on the result of the determination by the illuminance determination unit 251. Also, controls whether or not to perform supplemental lighting using the white light source 110 and the auxiliary light source 111 based on a timer 253.

[0058] The mode setting unit sets the mode selected by the user from among a first mode in which supplementary lighting is linked to the rise and fall of the sun, a second mode in which supplementary lighting for a predetermined period of time starts in conjunction with sunrise, and a third mode in which supplementary lighting for a predetermined period of time ends in conjunction with sunset. The mode setting unit also sets the supplementary lighting time in the second and third modes. These settings can be made, for example, by receiving an input from a computer connected to the network via the communication I / F 121. The timer 253 notifies the user of the lapse of the set supplementary lighting time.

[0059] Operation control of the illumination device 11 in the cultivation system 1 according to the second embodiment differs depending on the set mode. Moreover, the operation control in the first mode is similar to the operation control performed by the illumination device 11 in the first embodiment.

[0060] In the case where the second mode is set, when the elevation determination unit 250 determines that the elevation parameter indicating the power value obtained from any of the first solar panels 132 is equal to or greater than the first threshold value, the white light control unit starts the white light source 110 to emit light, the auxiliary light control unit starts the auxiliary light source 111 to emit light, and further the timer 253 starts. From the start to the end of the timer 253, the determination by the illuminance determination unit 251 is valid, and when it is determined that the light amount parameter indicating the power value obtained from the second solar panel 133 is equal to or greater than the second threshold value, the white light control unit stops the emission of the white light source 110. At this time, even if the elevation parameter is equal to or greater than the first threshold value, the emission of the white light source 110 stops.

[0061] Furthermore, when the illuminance determination unit 251 determines that the light amount parameter indicating the power value obtained from the second solar panel 133 is less than the second threshold value, the white light source 110 resumes emitting light. Until the timer 253 finishes counting down, the illuminance determination unit 251 continues to control the emission of the white light source 110.

[0062] When the second mode is set, the elevation determination unit 250 does not determine sunset. In other words, it does not determine whether the elevation parameter is less than the first threshold value. Instead, when the timer 253 ends, the white control unit stops the emission of the white light source 110, and the auxiliary light control unit stops the emission of the auxiliary light source 111. As a result, when the supplementary light time has passed since sunrise, supplementary light by the illumination device 11 stops until the next sunrise. When controlling the stop of supplementary light based on the passage of a predetermined time, the amount of supplementary light may be gradually reduced so that supplementary light stops over a certain period of time.

[0063] In the third mode, when the elevation determination unit 250 determines that the elevation parameter is less than the first threshold, the timer 253 starts. The timer 253 notifies the end of the timer when the time of day minus the supplementary light time has elapsed. When the timer 253 is notified of the end of the timer, the white light control unit starts the white light source 110 to emit light, and the supplementary light control unit starts the emission of supplementary light. In addition, the control of the white light source 110 based on the determination of the illuminance determination unit 251 functions effectively while the timer 253 is OFF, that is, from the notification of the end of the timer 253 to the start of the timer 253. This makes it possible to synchronize the passage of the supplementary light time with sunset.

[0064] If there is a large difference between the sunset time of the previous day and the sunset time of the current day, the timing of the sunset will differ significantly from the passage of the light supplement time, but it can be said that there are almost no environments in which the sunset time changes significantly during the day, except for certain locations such as the Antarctic and the Arctic. Therefore, basically, if the timing of the start of light supplement is determined based on the sunset time of the previous day, there will be no large difference between the sunset time of the next day and the timing of the end of light supplement, and appropriate light supplement control can be performed.

[0065] According to the cultivation system 1 of the second embodiment, it is possible to appropriately set whether to perform supplementary lighting according to the sunlight hours or for a period longer than the sunlight hours according to the user's intention. It is also possible to set supplementary lighting for a period shorter than the sunlight hours. In this way, the user can select one control pattern from multiple control patterns, and the lighting device 11 retains the selected control pattern as the setting. Note that such mode control can be set for each lighting device 11, so that some cultivation sections in the greenhouse 20 can be controlled in different modes from the other cultivation sections.

[0066] For example, in cultivation areas where vegetables suitable for the seasons of autumn and winter, when the daylight hours are short, the first mode can be used to control supplementary light, and in cultivation areas where vegetables suitable for the seasons of summer, when the daylight hours are long, the second or third mode can be used to control supplementary light.

[0067] Although the illumination device 11 that can set any one of the first to third modes has been described as the illumination device 11 applied to the cultivation system 1 according to the second embodiment, the illumination device 11 does not need to have a mode selection function. In other words, illumination devices 11 corresponding to each mode may be prepared and the illumination device 11 corresponding to the mode to be used may be installed. In that sense, even an illumination device 11 that does not have a mode setting unit can be used to configure the cultivation system 1 according to the second embodiment.

[0068] When realizing an illumination device 11 compatible with the second mode or an illumination device 11 compatible with the third mode, it is sufficient to have only one first solar panel 132. Since it is sufficient to detect either sunrise or sunset, if the illumination device 11 is arranged so that the first solar panel 132 is aligned with the direction of sunrise or sunset, supplemental light control is possible with one first solar panel 132 arranged on only one side surface.

[0069] <Third embodiment> The illumination device described so far has the second solar panel 133 installed on the upper surface. The installation surface is not limited to the upper surface, but while the second solar panel 133 is installed facing a specific surface, the position of the sun moves over time. Therefore, if the sunlight receiving area of ​​the second solar panel 133 does not move in accordance with the movement of the sun, the light receiving conditions of the second solar panel 133 will change, and even if the same intensity of light is radiated from the sun, the value of the power converted by the second solar panel 133 may differ.

[0070] By forming a hemispherical arrangement surface on the surface on which the second solar panel 133 is arranged, i.e., the surface opposite to the surface on which the light source is arranged, and arranging a plurality of second solar panels 133 on the hemispherical surface, it becomes possible to measure the amount of light taking into consideration the movement of the sun. If a determination is made based on the power value obtained from the second solar panel 133 arranged in a position that faces the sun, among the plurality of second solar panels 133, it is possible to suppress differences in light receiving conditions due to the movement of the sun.

[0071] The second solar panel 133 that obtains the greatest amount of power among the multiple second solar panels 133 can be regarded as the second solar panel 133 arranged in a position that faces the sun, and the accuracy of the orientation with respect to the sun depends on how the multiple solar panels are arranged. Accuracy can be improved by using many small solar panels and laying them out to cover a hemispherical surface. However, this would complicate the structure of the device, and would be expected to increase costs accordingly.

[0072] Although it is within the scope of the disclosure of the present invention to realize a growing system 1 having such an illumination device, a different realization method will be described for the illumination device 12 in the growing system 1 according to the third embodiment. The growing system 1 according to the third embodiment stores correction data obtained by measuring in advance, and based on the correction data, it is possible to suppress differences in light receiving conditions and perform illuminance determination with higher accuracy than the first and second embodiments.

[0073] Fig. 7 is a functional block diagram of an illumination device 12 according to a third embodiment. Various functions and processes described with reference to Fig. 7 are realized by the operation of a CPU 117 in an illumination device 12 having the hardware configuration shown in Fig. 4, for example. Therefore, the hardware configuration of the illumination device 12 according to the second embodiment may be similar to that of the illumination device 10 of the first embodiment.

[0074] The illumination device 12 differs from the illumination device 11 of the second embodiment in that it has an illumination correction unit 355 and a correction data storage unit 356. The correction data storage unit 356 stores correction data for determining a correction parameter indicating the amount of correction for the light quantity parameter obtained by the light quantity measurement unit 113. The illumination correction unit 355 determines the correction parameter for the obtained light quantity parameter and performs correction. The illumination determination unit 351 determines whether the light quantity parameter is equal to or greater than a second threshold value based on the corrected light quantity parameter.

[0075] Fig. 8 is a schematic diagram showing a simplified positional relationship between the illumination device 12 and the sun in order to explain the correction data to be obtained. The illumination device 12 is fixedly installed, and therefore the light quantity measuring unit 113 is also fixedly installed on the upper surface. On the other hand, the inclination of the sun changes over time, so the angle between the light quantity measuring unit 113 and the sun changes. For example, assume that at time t1, the sun is located at T1 shown in Fig. 8. At this time, in order to measure the amount of natural light from the sun located at T1 from the front, it is necessary to tilt the second solar panel 133 by an angle θ.

[0076] Therefore, if the difference between the value of the light amount measured when facing the sun directly and the light amount measured when tilted at angle θ is stored as correction data, the light amount when facing the sun directly can be calculated based on the light amount measured by the second solar panel 133. The correction data is data that indicates this difference.

[0077] On the other hand, if the sun is located at T2 at time t2, the second solar panel 133 faces the sun, so there is no difference and no need for correction. In this way, the measurement conditions for obtaining correction data change depending on the position of the sun. Therefore, it is desirable to measure measurement data in a similar climate during the same time period of the same month, when the panel faces the sun and when the panel is fixed to the lighting device 12, collect multiple pieces of data in a similar climate, and calculate the correction data by averaging or statistically.

[0078] FIG. 9 shows an example of a data configuration example of the correction data stored in the correction data storage unit 356. The correction data has items of month, time period, weather category, and correction parameter, and weather judgment conditions and correction parameters are set for each weather category. Correction data is prepared for each month for one year, but FIG. 9 shows correction data for May as an example. Note that correction data may be prepared in smaller units, such as every two weeks, instead of monthly, or may be prepared in seasonal units spanning multiple months. In addition, the monthly correction data is further divided by time period. In the example of FIG. 9, the data is divided into hourly intervals, but it may also be divided into shorter or longer time intervals.

[0079] The correction data defines weather judgment conditions and correction parameters according to the weather depending on the month and time period. In the example of FIG. 9, the weather categories are "weather: sunny" and "weather: other," and the weather is classified according to whether it is sunny or not. The weather categories may be divided more finely. For example, since there are different degrees of sunny, this may be divided more finely, and the weather category can be set appropriately. Weather judgment conditions are defined for determining that the weather falls into that weather category depending on each classified weather.

[0080] The weather judgment condition is determined from the measured value obtained under the same conditions as the measurement conditions when the illumination device 12 is installed in the cultivation system 1 during the time period of the day corresponding to the weather category. Since a correction process is performed according to the determined weather category, the weather category needs to be judged from the light amount parameter before correction. Therefore, it is preferable to aggregate the measured value obtained during a certain time period of a certain month into the weather category, compare the aggregated measurement results for each weather category, and determine the condition value that does not overlap with each other. In the example of FIG. 9, the weather judgment condition is set so that if the light amount parameter obtained from the light amount measured by the second solar panel 133 is X1 or more during the period from 5:00 to 6:00, the weather category is judged to be sunny, and if it is less than X1, the weather category is judged to be other weather categories.

[0081] The correction parameters are determined according to the weather category. Based on the example of FIG. 9, the correction parameters when the weather category is sunny in the relevant month and time period are obtained from the measurement results in the relevant time period on the day corresponding to the sunny weather category. Specifically, the measurement values ​​obtained under the same conditions as the measurement conditions when the illumination device 12 is installed in the cultivation system 1 and the measurement values ​​when facing the sun are measured, and the correction parameters are determined based on the difference between them. The correction parameters may be determined based on a value calculated statistically or averagely from the measurement results of multiple sunny days. The correction parameters are determined similarly for other weather conditions, and the correction parameters are determined for each weather category. In the example of FIG. 9, between 5:00 and 6:00, if the weather category is sunny, the correction is performed based on the correction parameter Y1, and if the weather category is other, the correction is performed based on the correction parameter Z1.

[0082] The illuminance correction unit 355 performs a correction process using the correction data stored in the correction data storage unit 356. Specifically, when the light quantity parameter obtained by the light quantity measurement unit 113 is obtained, the month and time period corresponding to the time of acquisition are identified. Next, a weather category to which the obtained light quantity parameter corresponds is determined based on the weather judgment conditions for the identified month and time period. In the example of FIG. 9, it is determined whether it is sunny or not. Then, a correction parameter corresponding to the identified month and time period and the determined weather category is obtained, and the light quantity parameter is corrected based on this correction parameter. After that, the illuminance judgment unit 351 obtains the corrected light quantity parameter and performs illuminance judgment based on the corrected light quantity parameter.

[0083] In this way, by holding a correction parameter that takes into consideration the difference between the measurement results of the light quantity measurement conditions in the illumination device 12 and the measurement conditions when actually facing the sun, and correcting with the correction parameter, the corrected light quantity parameter accurately reflects the irradiance actually irradiated to the plant. Therefore, the accuracy of the control based on the judgment result by the irradiance judgment unit 351, that is, the control to stop supplementary lighting by the white light source 110 when the irradiance of natural light is sufficient, is also improved.

[0084] In addition, by making corrections according to the weather category, it is possible to avoid a situation in which, for example, even when it is actually cloudy and sufficient radiation is not being obtained from natural light, it is determined that sufficient radiation is being obtained as a result of making corrections using the sunny correction parameters, and supplementary lighting by the white light source 110 is stopped.

[0085] That is, one weather category is identified from among multiple weather categories, and supplemental light control is performed using light intensity parameters corrected based on the weather category, thereby enabling supplemental light control according to the weather category. The supplemental light amount of the white light source may be adjusted based on the corrected light intensity parameters. For example, the required light amount of white light may be set, and the illumination device may supplement the white light source with enough light to compensate for the difference between this set value and the corrected light intensity parameter. Furthermore, supplemental light of the auxiliary light source may be controlled according to the weather category, or supplemental light of both the white light source and the auxiliary light source may be controlled.

[0086] <Fourth embodiment> The fourth embodiment is another configuration example of the cultivation system 1 described in the first to third embodiments. The system configuration of the cultivation system 1 according to the fourth embodiment is shown in FIG. 10. As shown in FIG. 10, the cultivation system 1 according to the fourth embodiment differs in that it has an environment measuring device 40 and a control device 30. Also, the illumination device 13 according to the fourth embodiment differs from the illumination device 13 of the first embodiment in that it does not have a light quantity measuring unit 113 and an elevation detection unit 112. Therefore, the illumination device 13 according to the fourth embodiment does not need to have a first solar panel 132 and a second solar panel 133.

[0087] In the cultivation system 1 of the fourth embodiment, the measurements made by the illumination device 13 using the first solar panel 132 and the second solar panel 133 are made by the environment measuring device 40. Therefore, the environment measuring device 40 is placed in a position that does not disturb the cultivation area, for example, on top of the greenhouse 20. The environment measuring device 40 measures lifting and lowering parameters and light quantity parameters, and may also make other more detailed measurements.

[0088] The control device 30 can be configured with a general computer equipped with a CPU, ROM, RAM, HDD, communication I / F, etc., and the measurement results obtained by the environment measuring device 40 are transmitted to the control device 30. Based on the measurement results, the control device 30 performs supplementary light control of the white light source 110 and auxiliary light source 111 for each illumination device 13. That is, the control device 30 performs elevation judgment and illuminance judgment, and based on the judgment results, controls the ON / OFF of the illumination control switch 114 and white control switch 115 of the illumination device 13. The specific control is the same as that described in the first to third embodiments.

[0089] According to the fourth embodiment of the cultivation system 1, there is no need to provide each illumination device 13 with configurations for environmental measurement, such as a lifting / lowering detection unit 112 or a light intensity measurement unit 113, and in a large-scale cultivation system 1 in which a large number of illumination devices 13 are arranged, advantages such as cost benefits, centralized control, and unified management can also be obtained.

[0090] <First Light Emitting Device 140> The above-mentioned first light emitting device 140 will now be described in more detail. The first phosphor preferably includes a nitride phosphor having a composition containing at least one element selected from Sr and Ca, Eu, Al, and Si. For example, the first phosphor may have a composition formula of (Sr,Ca)AlSiN 3 :Eu is an example of a nitride phosphor.

[0091] In this specification, a plurality of elements separated by a comma (,) in a composition formula means that at least one of the plurality of elements is contained in the composition. A plurality of elements separated by a comma (,) in a composition formula includes at least one element selected from the plurality of elements separated by the comma in the composition, and may contain a combination of two or more of the plurality of elements. In addition, in a formula showing the composition of a phosphor, the part before the colon (:) represents the host crystal, and the part after the colon (:) represents the activator element.

[0092] The first phosphor preferably contains a nitride phosphor having a composition represented by the following formula (I). (Ca 1-p-q Sr p Eu q )AlSiN 3 (I) In formula (I), p and q are numbers satisfying 0 ≦ p ≦ 1.0, 0 < q < 0.5, and 0 < p + q ≦ 1.0.

[0093] In the formula (I), Eu is an activating element of the nitride phosphor. In the formula (I), the variable q is the molar composition ratio of the activating element Eu in the composition represented by the formula (I). The variable q is preferably 0.0001 ≦ q ≦ 0.4, more preferably 0.001 ≦ q ≦ 0.3, and still more preferably 0.0015 ≦ q ≦ 0.2. In the formula (I), the variable p is the molar composition ratio of Sr in the composition represented by the formula (I). The variable p is preferably 0.001 ≦ p < 0.9, more preferably 0.002 ≦ p ≦ 0.8, and still more preferably 0.003 ≦ p ≦ 0.76.

[0094] The first phosphor may contain a Eu2+-activated nitride phosphor different from the nitride phosphor having the composition represented by the formula (I). Eu 2+ The activated nitride phosphor has a composition containing at least one element selected from Sr and Ca, Eu, Al, and Si, in addition to a nitride phosphor having a composition containing at least one element selected from the group consisting of alkaline earth metal elements and at least one element selected from the group consisting of alkali metal elements, and Eu 2+ Examples of the phosphor activated with include phosphors containing aluminate nitrides activated with.

[0095] Mn 4+ The halide phosphor activated with is preferably a phosphor containing a fluoride and having a composition containing at least one element or ion selected from the group consisting of alkali metal elements and ammonium ions (NH 4 + ) and at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and activated with Mn 4+ .

[0096] The first phosphor may contain at least one phosphor selected from the group consisting of phosphors having any of the compositions represented by the following formulas (II) to (VI). (i-j)MgO·(j / 2)Sc 2 O 3 ·kMgF 2 ·mCaF 2 ·(1-n)GeO 2 ·(n / 2)M 1 O 3 :vMn 4+ (II) In formula (II), M 1 is at least one selected from the group consisting of Al, Ga, and In, and i, j, k, m, n, and v are numbers satisfying 2≦i≦4, 0≦j<0.5, 0<k<1.5, 0≦m<1.5, 0<n<0.5, and 0<v<0.05, respectively. M 2 d M 3 e M 4 f Al 3-g Si g N h (III) In formula (III), M 2 is at least one element selected from the group consisting of Ca, Sr, Ba, and Mg, M 3 is at least one element selected from the group consisting of Li, Na, and K, M 4 is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and d, e, f, g, and h are numbers satisfying 0.80≦d≦1.05, 0.80≦e≦1.05, 0.001<f≦0.1, 0≦g≦0.5, and 3.0≦h≦5.0, respectively. (Ca 1-r-s-t Sr r Ba s Eu t ) 2 Si 5 N 8 (IV) In formula (IV), r, s, and t are numbers satisfying 0≦r≦1.0, 0≦s≦1.0, 0<t<1.0, and r + s + t≦1.0. (Ca,Sr)S:Eu (V) A 2 [M 5 1-u Mn 4+ u F 6 (VI) In formula (VI), A is at least one selected from the group consisting of K, Li, Na, Rb, Cs and NH 4 + and M5 is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and u is a number satisfying 0 < u < 0.2.

[0097] In the first aluminophosphate phosphor contained in the second phosphor, Cr is an activating element. In the second aluminophosphate phosphor, Ce and Cr are activating elements. In the composition of the second aluminophosphate phosphor, when the total molar composition ratio of Al and the second element M is 5, if the molar composition ratio of Ce is represented by the product of the variable x and 3, and the molar composition ratio of Cr is represented by the product of the variable y and 3, the variable x is a number satisfying 0.0002 < x < 0.50, and the variable y is a number satisfying 0.0001 < y < 0.05. By this, the doping amounts of Ce and Cr that are luminescence centers contained in the crystal structure of the second aluminophosphate phosphor are in an optimal range, it is possible to suppress a decrease in luminescence intensity due to a decrease in the luminescence centers, and conversely, to suppress a decrease in luminescence intensity due to concentration quenching caused by an increase in the doping amount, and increase the luminescence intensity.

[0098] The second phosphor preferably contains at least one phosphor selected from the group consisting of a first aluminophosphate phosphor having a composition represented by the following formula (VII) and a second aluminophosphate phosphor having a composition represented by the following formula (VIII). (Al 1-w Cr w ) 2 O 3 (VII) In formula (VII), w is a number satisfying 0 < w < 1. (Ln 1-x-yCe x Cr y ) 3 (Al 1―z M z ) 5 O 12 (VIII) In formula (VIII), Ln is at least one rare earth element selected from the group consisting of rare earth elements excluding Ce, M is at least one element selected from the group consisting of Ga and In, and x, y, and z are numbers satisfying 0.0002 < x < 0.50, 0.0001 < y < 0.05, and 0 ≤ z ≤ 0.8.

[0099] The second phosphor contains at least one aluminate phosphor and may contain two or more aluminate phosphors. Cr contained in the first aluminate phosphor having the composition represented by the formula (VII) is an activating element. In the formula (VII), the product of the variable w and 2 is the molar composition ratio of the activating element Cr in the composition represented by the formula (VII). The variable w is preferably 0 < w < 1, more preferably 0.00005 ≤ w ≤ 0.25, still more preferably 0.0005 ≤ w ≤ 0.15, and even more preferably 0.001 ≤ w ≤ 0.07. When the variable w is greater than 0 and less than 1, Cr, which is the activating element serving as the emission center, is contained, and the emission intensity can be increased.

[0100] Ce and Cr in the formula (VIII) are activating elements of the second aluminate phosphor having the composition represented by the formula (VIII). In the formula (VIII), the product of the variable x and 3 is the molar composition ratio of the activating element Ce in the composition represented by the formula (VIII). The variable x is preferably 0.0002 < x < 0.50, more preferably 0.001 ≤ x ≤ 0.35, and still more preferably 0.0015 ≤ x ≤ 0.30. In the formula (VIII), the product of the variable y and 3 is the molar composition ratio of the activating element Cr in the composition represented by the formula (VIII). The variable y is preferably 0.0001 < y < 0.05, more preferably 0.0005 ≤ y ≤ 0.04, and still more preferably 0.001 ≤ y ≤ 0.026.

[0101] In the formula (VIII), Ln is at least one rare earth element selected from the group consisting of rare earth elements excluding Ce, more preferably at least one selected from the group consisting of Y, Gd, Lu, La, Tb and Pr, and even more preferably at least one selected from the group consisting of Y, Gd and Lu.

[0102] In the formula (VIII), M is preferably at least one element selected from the group consisting of Ga and In, and M preferably contains Ga. In the formula (VIII), the product of the variable z and 5 is the molar composition ratio of the element M replacing Al in the formula (VIII). In the formula (VIII), the variable z is preferably 0≦z≦0.8, more preferably 0.001≦z≦0.6, and even more preferably 0.01≦z≦0.4.

[0103] At least one aluminate phosphor contained in the second phosphor has a composition that forms a garnet structure, and is therefore resistant to heat, light, and moisture. At least one aluminate phosphor contained in the second phosphor has an absorption peak wavelength of 380 nm or more and around 470 nm in the excitation absorption spectrum, and can sufficiently absorb light from the light-emitting element to increase the luminescence intensity of the second phosphor. Specifically, at least one aluminate phosphor contained in the second phosphor is, for example, (Al 0.09 Cr 0.01 ) 2 O 3 , (Al 0.9943 Cr 0.0057 ) 2 O 3 , (Y 0.977 Ce 0.009 Cr 0.014 ) 3 Al 5 O 12 , (Lu 0.983 Ce 0.009 Cr 0.008 ) 3 Al 5 O 12 , (Lu 0.9725 Ce 0.0175 Cr 0.01 ) 3 Al 5 O12 , (Y 0.9735 Ce 0.0125 Cr 0.014 ) 3 (Al 0.8 Ga 0.2 ) 5 O 12 , (Y 0.7836 Gd 0.1959 Ce 0.0125 Cr 0.008 ) 3 Al 5 O 12 , (Gd 0.9675 Ce 0.0125 Cr 0.02 ) 3 Al 5 O 12 etc.

[0104] The mass ratio of the second phosphor to the total amount 100% by mass of the first phosphor and the second phosphor is an amount such that the ratio R / B of the photon flux R of red light in a wavelength range of 620 nm to less than 700 nm to the photon flux B of blue light in a wavelength range of 400 nm to 490 nm is more than 4 and is not more than 50, and the ratio R / Fr of the photon flux R to the photon flux Fr of far-red light in a wavelength range of 700 nm to 780 nm is more than 0.1 and is not more than 10. The mass ratio of the second phosphor to the total amount 100% by mass of the first phosphor and the second phosphor is preferably in the range of 0.5% by mass to 99.5% by mass, more preferably in the range of 1% by mass to 99% by mass, even more preferably in the range of 1% by mass to 90% by mass, still more preferably in the range of 2% by mass to 80% by mass, even more preferably in the range of 5% by mass to 78% by mass, and particularly preferably in the range of more than 10% by mass to 75% by mass. When the mass ratio of the second phosphor to the total amount (100 mass%) of the first phosphor and the second phosphor is within the above range, the mixed color light can be controlled so that light emitted from the first phosphor and the second phosphor excited by the light from the light emitting element, together with light having an emission peak wavelength within a wavelength range of 380 nm to 490 nm, emits light in which the ratio R / B of the photon flux R to the photon flux B is more than 4 and not more than 50, and the ratio R / Fr of the photon flux R to the photon flux Fr is more than 0.1 and not more than 10. When the mass ratio of the second phosphor to the total amount (100 mass%) of the first phosphor and the second phosphor is in the range of 2 mass% to 80 mass%, the ratio R / B of the photon flux R to the photon flux B can be more than 10 and not more than 38, and the ratio R / Fr of the photon flux R to the photon flux Fr can be more than 1.5 and not more than 4.12, thereby providing a light emitting device that emits light that is more easily absorbed by the photoreceptors of plants and that is likely to promote photomorphogenesis.When the mass ratio of the second phosphor to the combined amount of the first phosphor and the second phosphor (100 mass%) is in the range of more than 10 mass% and not more than 75 mass%, the ratio R / B of the photon flux R to the photon flux B can be made to be more than 10 and not more than 38, and the ratio R / Fr of the photon flux R to the photon flux Fr can be made to be 1.5 or more and 4.0 or less, making it possible to provide a light emitting device that irradiates light that is more easily absorbed by the photoreceptors of plants and that is more likely to promote photomorphogenesis.

[0105] <Regarding the third light-emitting device 142> Next, the third light emitting device 142 will be described in more detail. The red phosphor contains at least one element selected from Sr and Ca, and Al in its composition, and Eu 2+ The red phosphor preferably contains a phosphor containing silicon nitride activated with Eu (hereinafter, may be referred to as "CASN phosphor"). The red phosphor has a composition containing at least one element selected from the group consisting of alkaline earth metal elements and at least one element selected from the group consisting of alkali metal elements, and contains Eu 2+ A phosphor containing aluminum nitride activated with Mn 4+ Fluorogermanate phosphor activated with Eu 2+ Phosphors containing sulfides of Ca or Sr activated with alkali metal elements and ammonium ions (NH 4 + and at least one element selected from the group consisting of Group 4 elements and Group 14 elements, 4+ It is preferable that the phosphor comprises at least one phosphor selected from the group consisting of fluoride-containing phosphors activated by fluorine.

[0106] The red phosphor specifically includes a phosphor containing any composition represented by the following formula (IX) or (X), or the above formulas (II), (IV) to (VI). Among them, the red phosphor preferably includes a phosphor containing silicon nitride having a composition represented by the following formula (IX). The phosphor containing any composition represented by the following formula (IX) or (X), or the above formulas (II), (IV) to (VI) emits red light by the excitation light from the light-emitting element, and in the emission spectrum of the light-emitting device, the half-value width of the emission peak existing in the range of 580 nm or more and 680 nm or less is 40 nm or more, and the emission peak has a relatively broad shape. Since the emission peak existing in the range of 580 nm or more and 680 nm or less of the red phosphor 70 has a half-value width of 40 nm or more and a relatively broad shape, more types of photoreceptors of plants can absorb the supplemented red light as light energy, or can sense the supplemented red light as a light signal, and can stably promote the growth of plants, or can enhance the functional nutrient components of plants, and can supply red light.

[0107] (Ca 1-s-t Sr s Eu t ) x Al u Si v N w (IX) In formula (IX), s, t, u, v, w and x are numbers satisfying 0≦s≦1, 0<t<1.0, 0<s + t<1.0, 0.8≦x≦1.0, 0.8≦u≦1.2, 0.8≦v≦1.2, 1.9≦u + v≦2.1, 2.5≦w≦3.5 respectively.

[0108] The phosphor containing the composition represented by formula (IX) is a CaAlSiN 3 :Eu phosphor or (Sr,Ca)AlSiN 3: It may also be represented as a Eu phosphor. In the above formula (IX), the variable t is the molar ratio of the activating element Eu in the composition represented by the above formula (IX). The variable t is preferably 0.0001 ≦ t ≦ 0.2, more preferably 0.0001 ≦ t ≦ 0.1, and even more preferably 0.0002 ≦ t ≦ 0.05. In the above formula (IX), the variable s is the molar ratio of Sr in the composition represented by the above formula (IX). The variable s is preferably 0 ≦ s ≦ 0.98, more preferably 0 ≦ s ≦ 0.95, and even more preferably 0 ≦ s ≦ 0.9.

[0109] (Ca a Sr 1-a-c-d Ba d Eu c ) f Li b Al 3 N e (X) In formula (X), a, b, c, d, e, and f are numbers that satisfy 0 ≦ a < 1.0, 0.8 ≦ b ≦ 1.05, 0.001 < c ≦ 0.1, 0 ≦ d ≦ 0.2, 3.0 ≦ e ≦ 5.0, and 0.8 ≦ f ≦ 1.05, respectively.

[0110] Also, if the ratio R / B of the photon flux R of red light in the range of 620 nm or more and 700 nm or less to the photon flux B of blue light in the range of 400 nm or more and 490 nm or less of the third light-emitting device 142 is in the range exceeding 20 and 200 or less, in addition to the red phosphor, it may contain other types of phosphors that emit light in a wavelength region other than the wavelength region of red light. Examples of other types of phosphors include green phosphors that absorb a part of the light emitted from the light-emitting element and emit green light, yellow phosphors that emit yellow light, far-red phosphors having an emission peak wavelength in a range exceeding 680 nm, and the like.

[0111] Specific examples of the green phosphor include phosphors containing any of the compositions represented by the following formulas (i) to (iii). M 11 8 MgSi 4 O 16 X 11 2 :Eu (i) In formula (i), M 11 is at least one selected from the group consisting of Ca, Sr, Ba, and Zn, and X11 is at least one selected from the group consisting of F, Cl, Br, and I. Si 6-b Al b O b N 8-b :Eu (ii) In formula (ii), b satisfies 0 < b < 4.2. M 13 Ga 2 S 4 :Eu (iii) In formula (iii), M 13 is at least one selected from the group consisting of Mg, Ca, Sr, and Ba. Further, as the green phosphor, for example, (Ca, Sr, Ba) 2 SiO 4 :Eu, Ca 3 Sc 2 Si 3 O 12 :Ce and other silicate phosphors can also be mentioned.

[0112] As the yellow phosphor, specifically, phosphors containing any of the compositions represented by the following formulas (iv) to (v) can be mentioned. M 14 c / e Si 12-(c+d) Al c+d O d N 16-d :Eu (iv) In formula (iv), M 14 is at least one selected from the group consisting of Sr, Ca, Li, and Y. c is from 0.5 to 5, d is from 0 to 2.5, and e is the charge of M 14 M 15 3 (Al, Ga) 5 O 12 :Ce (v) In formula (v), M 15 is at least one selected from the group consisting of Y or Lu, Gd, Tb.

[0113] ​As the far-red phosphor having an emission peak wavelength in a range exceeding 680 nm, specifically, there can be mentioned phosphors containing any of the compositions represented by the following formulas (vi) to (xi). (Al 1-f Cr f ) 2 O 3 (vi) In formula (vi), f is a number satisfying 0 < f < 1. (Ln 1-x-y Ce x Cr y ) 3 (Al 1-z M 16 z ) 5 O 12 (vii) In formula (vii), Ln is at least one rare earth element selected from the group consisting of rare earth elements excluding Ce, and M 16 is at least one element selected from the group consisting of Ga and In, and x, y, and z are numbers satisfying 0.0002 < x < 0.50, 0.0001 < y < 0.05, and 0 ≦ z ≦ 0.8. CaYAlO 4 :Mn (viii) LiAlO 2 :Fe (ix) CdS:Ag (x) GdAlO 3 :Cr (xi)

[0114] Although the present invention has been described above, the present invention is not limited to the specifically disclosed embodiments, and various modifications and changes can be made without departing from the scope of the claims.

Industrial Applicability

[0115] The devices or systems described in each embodiment can be used for plant cultivation and the like.

Explanation of Signs

[0116] 1… Cultivation system 10, 11, 12, 13… Lighting device 110...White light source 130...White light emitting device 111…Auxiliary light source 140...First light emitting device 141...Second light emitting device 142...Third light-emitting device 112…Lift / lower detection unit 113...Light quantity measuring unit 114...Illumination control switch 115…White control switch 116…Power supply unit 117…CPU 118...ROM 119...RAM 120…HDD 121...Communication I / F 250, 350...Ascent and Declination Judgment Section 251, 351...Illuminance judgment section 252, 352... Illumination control unit 253, 353…Timer 254, 354...Mode setting section 355…Illuminance correction section 356...Correction data storage unit 20…Green House 30...Control device 40…Environmental measuring device

Claims

1. A lighting device used for growing plants in combination with natural light, A white light source; An auxiliary light source that emits red light and far-red light; an illumination control unit that controls the degree of illumination of the white light source or the auxiliary light source; The illumination control unit is An illumination device that integrally controls the irradiation of the red light and the irradiation of the far-red light by controlling the degree of irradiation of light by the auxiliary light source.

2. The illumination device according to claim 1, wherein the illumination control unit maintains the intensity of irradiation of red light and far-red light from the auxiliary light source, and controls the intensity of irradiation of light from the white light source to be weakened or strengthened depending on the irradiance of light from natural light.

3. A plurality of the white light sources; A plurality of the auxiliary light sources; 3. The illumination device according to claim 1, wherein the illumination control unit controls a degree of irradiation of light from the plurality of white light sources or a degree of irradiation of light from the plurality of auxiliary light sources, and also controls the irradiation of the red light and the irradiation of the far-red light in an integrated manner by controlling the degree of irradiation of light from the plurality of auxiliary light sources.

4. the white light source includes a plurality of white light emitting devices; The illumination device according to claim 1 , wherein the auxiliary light source comprises a plurality of auxiliary light emitting devices.

5. the plurality of auxiliary light-emitting devices include at least one of a first light-emitting device or a second light-emitting device, and a third light-emitting device; The first light-emitting device is a ratio R / B of a photon flux R of red light in a wavelength range of 620 nm or more and less than 700 nm to a photon flux B of blue light in a wavelength range of 400 nm or more and 490 nm or less is greater than 4 and not more than 50, and a ratio R / Fr of the photon flux R of far-red light in a wavelength range of 700 nm or more and 780 nm or less is greater than 0.1 and not more than 10, The second light emitting device is a light emitting device in which R / B, which indicates a ratio of photon flux R in the range of 620 nm or more and less than 700 nm to photon flux B in the range of 380 nm or more and 490 nm or less, is 2.0 or more and 4.0 or less, and R / FR, which indicates a ratio of photon flux R in the range of 620 nm or more and less than 700 nm to photon flux FR in the range of 700 nm or more and 780 nm or less, is 0.7 or more and 13.0 or less, The third light-emitting device is 5. The illumination device according to claim 4, wherein the ratio R / B of the photon flux R of red light in the range of 620 nm to 700 nm to the photon flux B of blue light in the range of 400 nm to 490 nm is greater than 20 and is 200 or less.

6. A growing system using natural light, comprising a greenhouse and a plurality of lighting devices provided in the greenhouse, A plurality of white light sources; A plurality of auxiliary light sources that emit red light and far-red light; an illumination control unit that controls the degree of illumination of the white light source or the auxiliary light source from the plurality of illumination devices; The illumination control unit is A cultivation system that integrally controls the irradiation of the red light and the far-red light by controlling the degree of light irradiation from the auxiliary light source.

7. The cultivation system of claim 6, wherein the illumination control unit maintains the intensity of red light and far-red light emitted by the auxiliary light source, and controls the intensity of light emitted by the white light source to be weakened or strengthened depending on the irradiance of light from natural light.

8. A plurality of the white light sources; A plurality of the auxiliary light sources; The cultivation system described in claim 6 or 7, wherein the illumination control unit controls the degree of illumination of light from the multiple white light sources or the multiple auxiliary light sources, and also controls the illumination of the red light and the far-red light in an integrated manner by controlling the degree of illumination of light from the multiple auxiliary light sources.

9. the white light source includes a plurality of white light emitting devices; The cultivation system according to claim 6 , wherein the auxiliary light source comprises a plurality of auxiliary light emitting devices.

10. the plurality of auxiliary light-emitting devices include at least one of a first light-emitting device or a second light-emitting device, and a third light-emitting device; The first light-emitting device is a ratio R / B of a photon flux R of red light in a wavelength range of 620 nm or more and less than 700 nm to a photon flux B of blue light in a wavelength range of 400 nm or more and 490 nm or less is greater than 4 and not more than 50, and a ratio R / Fr of the photon flux R of far-red light in a wavelength range of 700 nm or more and 780 nm or less is greater than 0.1 and not more than 10, The second light emitting device is a light emitting device in which R / B, which indicates a ratio of photon flux R in the range of 620 nm or more and less than 700 nm to photon flux B in the range of 380 nm or more and 490 nm or less, is 2.0 or more and 4.0 or less, and R / FR, which indicates a ratio of photon flux R in the range of 620 nm or more and less than 700 nm to photon flux FR in the range of 700 nm or more and 780 nm or less, is 0.7 or more and 13.0 or less, The third light-emitting device is The cultivation system of claim 9, wherein the light emitting device has a ratio R / B of the photon flux R of red light in the range of 620 nm or more and 700 nm or less to the photon flux B of blue light in the range of 400 nm or more and 490 nm or less, which is greater than 20 and not greater than 200.

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