JP7233781B1 - Lighting equipment for growing plants for fruits and vegetables - Google Patents

Abstract

Kind Code: A1 A lighting for cultivating plants that enables forcing cultivation of fruit vegetables and an increase in the yield of fruits at low electricity cost, and enables cultivation with high light intensity and spectral light effective for photosynthesis with a light source of highly visible daylight white light. Provide equipment. A lighting device for growing a plant is provided with a plurality of light-emitting elements 12, and among the light-emitting elements, predetermined light-emitting elements that irradiate plants to be grown can emit light in red. NR, the number of predetermined light emitting elements capable of emitting blue light NB, the number of predetermined light emitting elements capable of emitting green light NG, and the number of predetermined light emitting elements capable of emitting white light. NW satisfies equations (1) through (5). NT = NR + NB + NG + NW (1) LR ≤ NR/NT ≤ UR (2) LB ≤ NB/NT ≤ UR (3) LG ≤ NG/NT ≤ UR (4) LW ≤ NW/NT ≤ UR (5) Figure 2

Description

TECHNICAL FIELD The present invention relates to a lighting device for growing plants for fruits and vegetables.

Conventionally, there are artificial light type plant factories and artificial light type seedling production apparatuses for cultivating plants using fluorescent lamps or LED lighting devices instead of sunlight. However, in either case, leafy vegetables such as leaf lettuce, which can be cultivated in a short period of about one month, herb cultivation, vegetable seedlings, and flower seedling primary seedlings (plug seedlings, etc.) are mainly produced, and fruit vegetables ( Strawberry) production is limited to about 5% of the total. The reason for this is the balance with the cost of electricity required for cultivation from sowing to harvesting (see Non-Patent Document 1).

Fruit vegetables such as tomatoes and strawberries require a cultivation period of about 100 to 120 days from sowing to harvesting when cultivated in an artificial light plant factory (closed plant factory). During the cultivation period, costs incidental to cultivation, such as electricity costs required for light and temperature control, labor costs, fertilizers, etc., are proportional to the cultivation period. This is one of the reasons why profits are poor in terms of management in the production of fruits and vegetables. To solve this problem, it is necessary to use light that allows fruit to be harvested in a short period of cultivation and that can be expected to increase the yield. In other words, it is necessary to have a spectrum of light that allows plants to efficiently perform photosynthesis and a light source that emits light with low energy and high intensity. According to the material described in Non-Patent Document 2, the breakdown of the electricity cost is 60% for lighting, 28% for air conditioning, and 11% for others (pumps, etc.), so lighting has a high ratio.

On the other hand, plant bodies require photosynthetic product conversion efficiency (light utilization efficiency) with light having the optimum spectrum for photosynthesis, high light intensity, and an increase in leaf area (light receiving rate). In particular, fruit vegetables such as tomatoes and strawberries receive light with a spectrum suitable for growth and light with high light intensity during the vegetative growth period, increasing the photosynthetic rate (amount of photosynthesis per unit time) and photosynthesis. Photosynthetic products (sucrose, starch, and cellulose) produced by the plant need to be efficiently stored in leaves, stems, and roots.

In fruit vegetables, during the reproductive growth period, photosynthetic products (source) stored in leaves, stems, and roots through photosynthesis are translocated and distributed to fruits (sink) in a well-balanced manner. It bears fruit and can increase the yield.

In order to solve these problems, many light-emitting technologies have been proposed so far, but it cannot be said that they have been solved due to the cost of electricity required for cultivation. For example, in the proposed technology so far, one or two of the peak tops of ultraviolet, red, blue, and far infrared rays are emitted in the emission spectrum, or the same light intensity as sunlight, which is well-balanced Emission spectrum. Emission spectra with one or two peak tops are produced by, for example, red-blue mixed-light LEDs, white-light LEDs, and mixed-light LEDs containing the above-mentioned peak wavelengths. Uniform light intensity and well-balanced emission spectra are produced by high-pressure sodium metal hydride lamps, three-wavelength fluorescent lamps, three-wavelength phosphor LEDs, and the like.

These techniques consume a lot of power to compensate for the light intensity. In artificial light type plant cultivation, light emission with low power consumption increases the rate of photosynthesis, shortens the cultivation period from sowing to harvest and increases the yield, thereby reducing the electricity cost per crop. Technology is required (see Non-Patent Document 3).

As a technique for compensating for light intensity, conventionally, as described in Patent Document 1, two reflectors are arranged parallel to both sides of a row of LED light sources mounted on a substrate so that the reflecting surfaces are aligned with the LED light sources. A technique has been proposed in which they are installed in an arrangement facing each other across a row.

JP 2015-99674 A

Greenhouse Horticulture Association, FY2021 Smart Greenhouse Development Project Report (Separate Volume 1) Large-scale Greenhouse Horticulture, Plant Factory Field Survey, Case Study, p. 22 Figure 26 Main cultivated items (artificial light type) <https://jgha. com/wp-content/uploads/2022/04/TM06-03-bessatsu1. pdf> Greenhouse Horticulture Association, 2021 Smart Greenhouse Development Business Report (Separate Volume 1) Large-scale Greenhouse Horticulture, Plant Factory/Field Survey/Case Study, p. 50 Figure 65 Cost ratio by cultivation type (artificial light type), p. 51 Figure 66 Breakdown of electricity cost (artificial light type) <https://jgha. com/wp-content/uploads/2022/04/TM06-03-bessatsu1. pdf> Greenhouse Horticulture Association, FY2021 Smart Greenhouse Development Project Report (Separate Volume 1), Large-scale Greenhouse Horticulture, Plant Factory/Field Survey/Case Study, P. 39 Figure 50 Earnings for the last few years <https://jgha. com/wp-content/uploads/2022/04/TM06-03-bessatsu1. pdf> Department of Biological Sciences, Graduate School of Science, The University of Tokyo Ichiro Terashima, Introduction of Research, p. 17 "4. Why Leaves Are Not Black: Optical Properties of Leaves", p. 18 “5. Light environment inside leaves and construction principle of photosynthetic system”, [searched on July 26, 2020], Internet <https://photosyn. jp/journal/sections/kaiho57-3. pdf> Introduction of Ichiro Terashima, (1) Relationship between the light environment inside the leaf and the photosynthesis of the leaf, Fig. 5, Fig. 6 Differential quantum yield measurement method, [searched July 26, 2022], Internet <http: //www. bs. s. u-tokyo. ac. jp/~seitaipl/personal/terashima/terashima_j. html>

Vegetables cultivated in plant factories include root vegetables whose roots are edible, leafy vegetables whose leaves and stems are edible, and fruit vegetables whose fruits are edible. Among these, fruit vegetables include, for example, tomatoes, strawberries, and the like. Harvesting in a short period of time is an important issue in the cultivation of fruit vegetables in a plant factory. However, the white LEDs, blue LEDs, red LEDs, far-red LEDs, and ultraviolet LEDs used in prior art LED lighting devices have room for further improvement in increasing the photosynthetic rate of fruit vegetables.

By the way, it has been thought that green light is unnecessary for photosynthesis. That is, it is thought that the leaves look green because the green light is reflected instead of being absorbed by the leaves, and green light has been regarded as unnecessary light in cultivation using artificial light. However, green light is actually required for photosynthesis, although it is not as absorbed by leaves as red and blue light. Green light is reflected and absorbed many times inside the leaf due to the development of palisade tissue and sea surface tissue throughout the leaf. Especially in artificial light cultivation of fruit vegetables and flowers, the light intensity of white light is increased in order to increase the photosynthetic rate, but there is a limit (light saturation point) in the absorption of light by photosynthesis of plants, and high intensity , the chloroplasts on the leaf surface reach the light saturation point and red and blue light are dissipated as heat without being needed for photosynthesis. On the other hand, the chloroplast on the back surface of the leaf has not reached the light saturation point. At this point, green light also reaches the underside of the leaf, so green light drives photosynthesis in chloroplasts that have not yet reached the photosaturation point, resulting in a faster rate of photosynthesis with green light than with red or blue light. becomes. Therefore, green light is indispensable for photosynthesis along with red light and blue light. In this way, an improvement that utilizes green light is desired (see Non-Patent Documents 4 and 5).

In addition, in forcing cultivation of fruit vegetables by artificial light cultivation, it is necessary to expand the leaf area of the plant body, expand the light receiving area so as to receive more light, and store photosynthetic products by photosynthesis. . An increase in photosynthetic products prevents fruit dropping (increases the rate of fruit setting) and shortens the number of days required for fruit maturation. Thus, increasing the photosynthetic rate of fruit vegetables also leads to an increase in yield.

In the case of tomatoes and strawberries, the degree of maturity can be estimated by looking at the skin color of the fruit. However, the illumination light emitted from the above-mentioned LED lighting equipment in indoor facilities may cause differences in light quality and uneven illumination due to the light source color different from sunlight. However, unlike the color of the skin when exposed to sunlight, it may be mistakenly seen by workers. Alternatively, there is a risk of overlooking factors that inhibit growth due to physiological disorders that occur in plants. Therefore, there is a demand for a plant-growing lighting device capable of illuminating in a daylight color close to that of sunlight. Specifically, when the color temperature is about 6500 Kelvin, the visibility of the skin color of the fruit is high, and when the color rendering Ra is about 95, daylight lighting close to sunlight is obtained.

In response to the above-mentioned demands, the present invention realizes short-term cultivation and an increase in fruit yield by irradiating light with a spectrum that can increase the photosynthetic rate of fruit vegetables and a high light intensity. To provide a plant-growing lighting device for fruits and vegetables as lighting that emits daylight color with high quality.

In order to achieve the above object, the present invention has the following configurations.

(1) comprising a plurality of light-emitting elements (for example, LED elements 12);
Among the light emitting elements, among the light emitting elements _, the number of the predetermined light emitting elements that irradiate the plant to be grown is N _T , the number of the predetermined light emitting elements that can emit red light, the number of the predetermined light emitting elements that can emit blue light, and the predetermined light emitting elements that emit blue light. The number of elements capable of emitting light N _B , the number of elements capable of emitting green light among the predetermined light emitting elements N _G , and the number of elements capable of emitting white light among the predetermined light emitting elements N _W A lighting device for growing plants for fruits and vegetables (for example, an LED lighting device 1) that satisfies (5).
N _T = N _R + N _B + N _G + N _W (1)
28/216≦N _R /N _T ≦44/216 (2)
14/216≦N _B /N _T ≦22/216 (3)
14/216≦ _NG / _NT ≦22/216 (4)
128/216≦N _W /N _T ≦160/216 (5)

According to (1), the number of elements that emit red light, the number of elements that emit blue light, the number of elements that emit green light, and the number of elements that emit white light are calculated using the above equations (1) to (5). It becomes a ratio that satisfies This makes it possible to combine the red and blue luminescence required for photosynthesis with the green luminescence that drives photosynthesis in the chloroplasts that have not reached light saturation in the back of the leaves and increases the light utilization efficiency of plants. It is possible to irradiate plants with light of the spectrum of , and it is possible to provide a lighting device for growing fruits and vegetables suitable for cultivation of fruits and vegetables aiming at forcing cultivation and yield increase.

Moreover, according to (1), the predetermined light-emitting elements emit light in each color at a ratio that satisfies the above formulas (1) to (5), so that it is possible to illuminate with a daylight color that is close to sunlight and has high visibility of the actual color. Providing a lighting device for growing plants is compatible with irradiating plants with the light of the spectrum peculiar to the present invention.

(2) In (1), the element capable of emitting red light is a red light emitting element (e.g., red LED element 12R), and the element capable of emitting blue light is a blue light emitting element (e.g., blue LED element 12B ), wherein the element capable of emitting green light is a green light emitting element (e.g., green LED element 12G), and the element capable of emitting white light is a white light emitting element (e.g., white LED element 12W); Lighting equipment for growing plants for fruits and vegetables.

According to (2), since the element capable of emitting light in each color is a monochromatic light emitting element, it is possible to irradiate a stronger mixed color light than in the case where the phosphor light emitting elements which can be tuned in color are caused to emit light in respective colors. As a result, it is possible to irradiate the plant with light that combines red and blue light emission necessary for photosynthesis and green light emission that enhances the light utilization efficiency of the plant with much higher light intensity.

Further, according to (2), the elements that emit light in each color are monochromatic light emitting elements, and the elements that emit white light are white light emitting elements. can be prevented.

(3) The plant-growing lighting device for fruits and vegetables according to (2), including a light-emitting portion in which a plurality of basic arrangements having 12 predetermined light-emitting elements are arranged.

According to (3), a ratio that satisfies the above equations (1) to (5) is achieved in the basic arrangement. As a result, in a basic arrangement that illuminates a narrower range than the entire range illuminated by the lighting device for growing plants, the light of the spectrum and light intensity peculiar to the present invention suitable for forcing cultivation and yield increase of fruits and vegetables can be realized.

Therefore, according to (3), it is possible to realize a daylight color with even less color unevenness of the irradiated light. By irradiating the plant body with light without color unevenness in this way, it is possible to further increase the photosynthetic rate, and the plant can grow more uniformly and stably.

In addition, according to (3), in the basic arrangement, it is possible to realize the light and light intensity of the spectrum peculiar to the present invention suitable for forcing cultivation and yield increase of fruit vegetables. It is no longer necessary to separate the plant-growing lighting device from the plant to be grown for the purpose of maintaining the light intensity. As a result, the plant-growing lighting device can be arranged closer to the plant to be grown, and the irradiation efficiency can be improved.

(4) In (3), the basic arrangement is such that, in the light emitting portion, the red light emitting elements are arranged at approximately the same intervals, the blue light emitting elements are arranged at approximately the same intervals, and the green light emitting elements are arranged at approximately the same intervals. A plant for fruit vegetables having a configurable arrangement in which colored light-emitting elements including the red light-emitting element, the blue light-emitting element, and the green light-emitting element are arranged at the same intervals and are arranged at substantially the same intervals. Growing lighting device.

According to (4), since the light emitting elements of each color are arranged at approximately the same intervals, it is possible to further reduce color unevenness of the irradiated light. Moreover, according to (4), since the red, green, and blue monochromatic light emitting elements are arranged at approximately the same intervals, the white light emitting element is arranged between the red, green, and blue monochromatic light emitting elements. It becomes arrangement|positioning and can further reduce the color nonuniformity of irradiation.

(5) In (1) to (4), a reflector (for example, a , and two or more reflecting surfaces 26 (mirror-finished reflecting plate or mirror-plating).

According to (5), it is possible to increase the amount of light irradiated to the plant without increasing the power consumption of the light emitting element. Therefore, according to (5), it is possible to improve efficiency and save power as a lighting fixture.

(6) In (1) to (5), at least some or all of the plurality of light emitting elements are linearly arranged, and each of the linearly arranged light emitting elements has substantially the same shape and substantially rectangular parallelepiped shape. and in each of the linearly arranged light emitting elements, the direction in which the positive and negative terminals of the chip LED face each other is substantially perpendicular to the direction in which the light emitting elements are arranged. Lighting equipment for growing plants.

According to (6), since the light-emitting element is a chip LED, power saving can be achieved. Moreover, since the direction in which the positive and negative terminals of the chip LED face each other is substantially orthogonal to the direction in which the light emitting element is arranged, there is no need to arrange wiring or the like between the adjacent chip LEDs. Therefore, according to (6), it is possible to shorten the interval between the light emitting portions of the chip LED. Thereby, according to (6), it is possible to realize daylight color with less color unevenness of the irradiated light.

(7) A plant-growing lighting device for fruits and vegetables according to (1) to (6), further comprising at least one of an ultraviolet light LED element and a far-infrared light generating element.

According to (7), by irradiating near-ultraviolet rays, it becomes possible to make pollinating insects such as bees and bumblebees, which are necessary for pollination of fruit vegetables, to act actively in the flowering stage of fruit vegetables. It becomes possible to efficiently perform pollination by pollinating insects. This makes it possible to increase the likelihood of more well-shaped fruit set than the method of pollination using a human brush. Irradiation with far-infrared light can be expected to increase leaf area and promote stem elongation. As a result, it becomes possible to increase the rate of light reception and increase the rate of photosynthesis, thereby increasing the accumulation of photosynthetic products of fruits and vegetables.

INDUSTRIAL APPLICABILITY According to the present invention, lighting for cultivating fruit vegetables that can be irradiated with spectrum light and high light intensity emission that can enhance forcing cultivation and yield increase of fruit vegetables, and that can be illuminated with daylight color with high visibility. Equipment can be provided. In addition, according to the present invention, since the cultivation period from sowing to fruit harvesting can be shortened with low power consumption lighting, a reduction in cultivation costs can be expected.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the external appearance of the LED lighting apparatus 1 in one Embodiment of this invention. 2 is a plan view showing the configuration of an LED substrate 10; FIG. 1 is an explanatory diagram schematically showing the structure of an aluminum substrate 11 in an LED lighting device 1 according to one embodiment of the present invention; FIG. FIG. 3 is an explanatory diagram showing an aluminum substrate 11 for serially connecting a plurality of LED elements 12 of an LED substrate 10; FIG. 3 is an explanatory view showing an aluminum substrate 11 for connecting a group of a plurality of LED elements 12 of an LED substrate 10 connected in series in parallel. 4 is a diagram showing an example of a spectrum of light emitted from the LED lighting device 1; FIG. It is a figure which shows distribution of the light of the shelf surface in a cultivation shelf. It is a photograph 40 days after sowing showing the growth difference of the seed propagation strawberry "Yotsuboshi" in the cultivation test using four types of LED lighting devices, from the left: no white light LED lighting reflector, white light LED lighting 4A and 4B show cases of using an LED lighting device with a reflector, without the RGBW four-color mixed light source white LED lighting reflector according to the present invention, and with an RGBW four-color mixed light source white LED lighting reflector according to the present invention. It is a photograph 40 days after seeding showing the growth difference of dwarf low-stage cherry tomatoes in a cultivation test using four types of LED lighting devices. From the left, without a white light LED lighting reflector, with a white light LED lighting reflector, A case of using an RGBW four-color mixed light source without a white LED lighting reflector according to the present invention and an LED lighting device with an RGBW four-color mixed light source white LED lighting reflector according to the present invention are shown. It is a photograph 50 days after sowing showing the growth difference of dwarf low-stage cherry tomatoes in a cultivation test using four types of LED lighting devices. From the left, without a white light LED lighting reflector, with a white light LED lighting reflector, A case of using an RGBW four-color mixed light source without a white LED lighting reflector according to the present invention and an LED lighting device with an RGBW four-color mixed light source white LED lighting reflector according to the present invention are shown. FIG. 3 is a plan view schematically showing a modification of the LED lighting device 1 according to one embodiment of the present invention; It is explanatory drawing which shows the aspect which mounts two rows of several LED element 12 on one aluminum substrate 11 in a modification.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In the plant-growing lighting device of the present embodiment, the type of light source may be any light source other than the light source, such as micro LEDs, mini LEDs, polymer organic ELs, and the like.

From the viewpoint of power saving and ease of construction, the light sources are preferably LEDs in current optical technology. Hereinafter, the LED lighting device 1 will be described as the lighting device for cultivating plants for fruit vegetables according to the present invention. It goes without saying that a person skilled in the art who has access to the description of the present embodiment can similarly configure a lighting device for growing fruit vegetables using other light sources.

[Configuration of LED lighting device 1]
FIG. 1 is a perspective view showing the appearance of an LED lighting device 1 according to one embodiment of the present invention.

The LED lighting device 1 includes an LED substrate 10 and a heat sink 20. As shown in FIG.

[LED board 10]
FIG. 2 is a plan view showing the configuration of the LED substrate 10. As shown in FIG. The LED substrate 10 includes an elongated aluminum substrate 11 and a plurality of LED elements 12 made of chip LEDs, and functions as a light-emitting portion in which the plurality of LED elements 12 are arranged in a predetermined arrangement.

The predetermined arrangement is not particularly limited. The predetermined layout is selected from arbitrary layouts such as linear layout, circular layout, curved layout, plane layout, curved layout, and three-dimensional layout according to the type, layout, shape, etc. of the plants to be irradiated. It is possible. The aluminum substrate 11 is not limited to a long one and can be of any shape according to the selected arrangement.

Preferably, the predetermined arrangement comprises a linear arrangement. As a result, the plants can be arranged linearly on the shelf and efficiently irradiated with light by the artificial light multi-tiered shelf cultivation method.

[Heat sink 20]
Returning to FIG. 1, the heat sink 20 is made of an elongated cylindrical body made of aluminum. and a lower surface portion 23 connected to the ends of the side portions 22, 22.

The lower surface portion 23 has a C-shaped end surface and includes a rail-shaped storage portion 24 for storing the LED substrate 10 and slope portions 25 obliquely extending from both sides extending along the longitudinal direction of the storage portion 24 . . The tip of the slope portion 25 is connected to the ends of the side portions 22 , 22 .

A reflecting surface 26 is formed on the surface of the slope portion 25 on the side of the LED substrate 10, and is in contact with a flat and mirror-finished reflecting plate. The reflecting surface 26 may be mirror-plated in the longitudinal direction on the surface of the slope portion 25 facing the LED substrate 10 . Reflective surface 26 is positioned at an angle of 70 degrees to the plane of LED substrate 10 . It is desirable that the angle of the reflecting surface 26 with respect to the plane of the LED substrate 10 is in the range of 65 to 70 degrees.

When the LED substrate 10 is stored in the storage portion 24 , a plurality of LED elements 12 (see FIG. 2 ) face a slit-shaped open area extending in the central portion of the storage portion 24 , and both sides of the plurality of LED elements 12 face each other. Reflective surfaces 26, 26 are arranged.

Heat generated in the LED substrate 10 when the LED elements 12 are caused to emit light is released to the outside through the heat sink 20, thereby cooling the LED substrate 10. As shown in FIG.

The heat sink 20 is also provided with a power supply device or the like that converts AC power into DC power and supplies electricity to the LED substrate 10 . This power supply supplies a direct current to the wiring portion 111a (see FIG. 3) and the wiring portion 111b (see FIG. 3) of the aluminum substrate 11, thereby causing the plurality of LED elements 12 connected in parallel to emit light.

Next, an example of a preferable mode in which the LED substrate 10 is configured by arranging a plurality of LED elements 12 made of chip LEDs in a straight line on the long aluminum substrate 11 will be described. It goes without saying that a person skilled in the art who has access to the description of the present embodiment can similarly configure a plant-growing lighting device in which combinations of different light sources and different arrangements are selected.

(Aluminum substrate 11)
FIG. 3 is an explanatory diagram schematically showing the configuration of the aluminum substrate 11 of the LED lighting device 1 according to one embodiment of the present invention. The aluminum substrate 11 includes a wiring portion 111 and a plurality of mounting portions 112 on which the LED elements 12 are placed and fixed by soldering or the like.

The wiring portion 111 includes a wiring portion 111 a connected to one terminal of the LED element 12 and a wiring portion 111 b connected to the other terminal of the LED element 12 . The wiring portion 111 a and the wiring portion 111 b extend parallel to each other along the longitudinal direction of the aluminum substrate 11 with the same distance as the distance between the anode terminal and the cathode terminal of the LED element 12 . In the following description, the anode terminal may be called a positive electrode, and the cathode terminal may be called a negative electrode.

A plurality of mounting portions 112 are provided at equal intervals along the longitudinal direction, and wiring portions 111a and 111b are arranged on the mounting portions 112 .

FIG. 4 is an explanatory diagram showing the aluminum substrate 11 for connecting the plurality of LED elements 12 of the LED substrate 10 in series. In the aluminum substrate 11 shown in FIG. 4, the wiring portion 111a and the wiring portion 111b are formed in a broken line shape, and terminals of two adjacent LED elements 12 are connected by one broken line. The wiring portion 111a and the wiring portion 111b are arranged in the mounting portion 112, and the broken line portion is arranged between the adjacent mounting portions 112, 112. As shown in FIG. Moreover, the wiring portion 111a and the wiring portion 111b are shifted by one LED element 12 . In other words, the central portion of one dashed line in the wiring portion 111a faces the discontinuity of the dashed line in the wiring portion 111b.

The LED elements 12 are fixed to the mounting portion 112 of the aluminum substrate 11 wired in this manner by soldering or the like in order while alternately changing the positions of the anode terminal and the cathode terminal. A plurality of LED elements 12 are connected in series on an aluminum substrate 11 .

If the plurality of LED elements 12 of the LED substrate 10 are connected in series, the current flowing through each of the plurality of LED elements 12 can be made the same without using a complicated circuit configuration in which each LED element 12 is provided with a current adjusting resistor or the like. can be done. Thereby, the brightness of the plurality of LED elements 12 can be made uniform. Moreover, if the plurality of LED elements 12 of the LED substrate 10 are connected in series, a power supply with a high driving voltage can be effectively used.

If the plurality of LED elements 12 of the LED substrate 10 are connected in parallel, even if one of the plurality of LED elements 12 fails, the other LED elements 12 can continue to light. If the plurality of LED elements 12 of the LED substrate 10 are connected in parallel, it is possible to easily provide an independent switch for each of the plurality of LED elements 12 and turn each of the plurality of LED elements 12 on and off individually. Become. Also, if the plurality of LED elements 12 of the LED substrate 10 are connected in parallel, the LED elements 12 can be caused to emit light with the minimum voltage required to drive the LED elements 12 .

By changing the pattern of the wiring portion 111a and the wiring portion 111b, the LED elements 12 of the same color can be connected in series and the LED elements 12 of different colors can be connected in parallel, or the LED elements 12 of the basic arrangement L can be connected in series and used as the basic arrangement. It is also possible to connect in parallel an array unit in which the layout L or the basic layout L is repeated a certain number of times.

FIG. 5 is an explanatory diagram showing an aluminum substrate 11 for connecting in parallel a group of a plurality of LED elements 12 of the LED substrate 10 connected in series. On the plate surface of the aluminum substrate 11, a wiring portion 111a and a wiring portion 111b extending linearly in the longitudinal direction and a plurality of wiring portions 111c having a substantially Z-shaped crank shape are formed. The wiring portion 111c has a central portion extending in a direction perpendicular to the longitudinal direction of the wiring portion 111a, and one end portion and the other end portion extending in opposite directions from both ends of the central portion along the longitudinal direction of the wiring portion 111a. and The wiring portion 111a, the wiring portion 111b, and the wiring portion 111c are not connected to each other. The wiring portion 111a and the wiring portion 111b are arranged so as to face each other with an interval slightly longer than the length between the two poles of the LED element 12 . The wiring portion 111a has an extension portion 111d that extends to the position of the positive electrode of the first LED element 12 in the basic layout L. As shown in FIG. The wiring portion 111b has an extension portion 111e extending to the position of the negative electrode of the last LED element 12 in the basic layout L. As shown in FIG. The first wiring portion 111c is arranged such that one end is positioned between the extending portion 111d and the wiring portion 111b and the other end is adjacent to the wiring portion 111a. The second wiring portion 111c has one end located between the other end of the first wiring portion 111 and the wiring portion 111b, and is arranged so that the other end is close to the wiring portion 111a. One end of the third wiring portion 111c is positioned between the other end of the second wiring portion 111 and the wiring portion 111b, and the other end is arranged so as to be close to the wiring portion 111a. A 23rd wiring portion 111c is arranged in the same manner, and the other end of this wiring portion 111c is arranged between the wiring portion 111a and the extension portion 111e. In addition, the 23rd wiring portion 111a is provided with a wire on the side of the other end of the 23rd wiring portion 111c so as to face the extending end of the extending portion 111e with a slight deviation from the center of the extending portion 111e. , a second extending portion 111d is formed. Then, the extending portion 111d and one end of the first wiring portion 111c, the other end of the upstream wiring portion 111c and one end of the one downstream wiring portion, the other end of the last wiring portion 111c and the extension A mounting portion 112 is formed in each of the portions 111e. By mounting the LED elements 12 on the mounting portion 112 of the aluminum substrate 11 configured in this way, the LED elements 12 of the basic arrangement L can be connected in series and connected in parallel in units of the basic arrangement L.

(LED element 12)
Return to FIG. The LED element 12 is composed of a rectangular parallelepiped chip LED, and an anode terminal is arranged at one end of the rectangular parallelepiped in the longitudinal direction, and a cathode terminal is arranged at the other end. Therefore, the LED element 12 is mounted on the mounting portion 112 in the direction in which the anode terminal and the cathode terminal face each other, that is, the direction in which the longitudinal direction of the rectangular parallelepiped shape is perpendicular to the longitudinal direction of the aluminum substrate 11 . be done. In this embodiment, the anode terminal of the LED element 12 is fixedly connected to the wiring portion 111a by soldering or the like, and the cathode terminal of the LED element 12 is fixedly connected to the wiring portion 111b by soldering or the like. Thereby, the plurality of LED elements 12 are connected in parallel.

The plurality of LED elements 12 can emit four kinds of mixed-color light of red, blue, green, and white. Thereby, it is possible to realize a spectrum light suitable for growing a plant to be irradiated (a plant to be irradiated from the LED element 12).

Although the type of the plant to be irradiated is not particularly limited, the plant to be irradiated is preferably fruit vegetables and flowering plants that require a large amount of light. When the plants to be irradiated are fruits and vegetables and flowering plants, it is possible to expect an effect of improving productivity brought about by the promotion of photosynthesis by the mixed light of four kinds of light emitted from the LED element 12 .

The plants to be irradiated are more preferably fruit vegetables among vegetables. “Fruit vegetables” refers to vegetables whose fruits or seeds are edible, and examples thereof include tomatoes, cucumbers, pumpkins, eggplants, strawberries, melons, and watermelons. Since the plants to be irradiated are fruits and vegetables, out of the light emitted from the LED element 12, blue light is used to suppress stem elongation and growth (elongation). Flower bud formation effect can be expected. Also, among the light emitted by the LED element 12, the effect of increasing the photosynthetic rate can be expected by improving the amount of light absorbed by the interior of the leaf due to the green light. Furthermore, of the light emitted by the LED element 12, by compensating for the lack of light intensity of red, blue, and green due to daylight color light, the photosynthetic rate is increased, and the accumulation of photosynthetic products in leaves, stems, and roots increases. Proper translocation and distribution of photosynthetic products to the fruit may lead to early harvest and increased yield.

Tomatoes and/or strawberries are particularly preferred among fruit vegetables. Since the plants to be irradiated include tomatoes and/or strawberries, the white light produced by the daylight-colored light emitted by the LED element 12 has good visibility, and the degree of maturity can be estimated by looking at the skin color of the fruit at the time of harvest. .

Regarding the realization of a spectrum suitable for growing fruits and vegetables, the number of predetermined light emitting elements among light emitting elements that irradiate plants to be grown is N _T , and the number of elements capable of emitting red light among the predetermined light emitting elements is N _{R .} , the number N _B of predetermined light emitting elements capable of emitting blue light, the number N _G of predetermined light emitting elements capable of emitting green light, and the number N _W of predetermined light emitting elements capable of emitting white light are , satisfies equations (1) through (5).
N _T = N _R + N _B + N _G + N _W (1)
L _R ≤ N _R /N _T ≤ U _R (2)
_LB ≤ _NB / _NT ≤ _UB (3)
_LG ≦ _NG / _NT ≦ _UG (4)
_{LW≤NW / NT≤UW} ( ₅ )

The ratio N _R /N _T of the elements capable of emitting red light is preferably 36/216. As a result, it can be expected that the promotion of flowering and the improvement of fruiting can be achieved at the same time. The reason why _NR / _NT is set to 36/216 is to increase the light intensity of red light, which contains many photons, but is lower in light intensity than blue light and green light.

The ratio N _B /N _T of the elements capable of emitting blue light is preferably 18/216. This can be expected to further promote photosynthesis. It can be expected to further promote this and further improve the control of stem elongation and hypertrophic growth of plants.

The ratio N _G /N _T of the elements capable of emitting green light is preferably 18/216. As a result, the light utilization efficiency of plants can be further increased, the rate of photosynthesis can be increased, and an increase in photosynthetic products can be expected. Furthermore, if the white light intensity (high brightness white light LED chip) is increased to reach the light saturation point on the leaf surface, it may be expected to increase the photosynthetic rate on the underside of the leaf.

The ratio N _W /N _T of the elements capable of emitting white light is preferably 144/216. As a result, the white monochromatic light element capable of emitting white light with high light intensity compensates for the lack of light intensity of mixed white light of red, green, and blue monochromatic lights, thereby increasing the photosynthetic rate and cultivating. Shortening of the period and increase in yield of stable fruits can be expected. In addition, the mixed color light emitted from these four color elements is daylight color light with a high color rendering property of Ra 95, and is expected to improve visibility. As a result, it can be expected that the detection of leaf disease during the cultivation process and the improvement in the accuracy of judging the degree of maturity based on the coloring of the fruit can be achieved at the same time.

The values of _NR / _NT , _NB / _NT , _NG / _NT , and _NW / _NT are preferably those described above, but _NR / _NT , _NB / _NT , There may be a range in the values of N _G /N _T and N _W /N _T . The lower limit L _R of the _NR / _NT value is 28/216, the upper limit _UR of the _NR / _NT value is 44/216, and the lower limit L _R of the _NB / _NT value is 14/216. , the upper limit _UB of the value of _NB / _NT is 22/216, the lower limit _LR of the value of _NG / _NT is 14/216, and the upper limit _UG of the value of _NG / _NT is 22/216. 216, the lower limit L _R of the value of N _W /N _T is 128/216 , and the upper limit U _W of the value of N _W /N _T is 160/216 , the above effects can be expected.

When the number of elements for each color satisfies the above lower and upper limits and formulas (1) to (5), the number of elements emitting red light, the number of elements emitting blue light, the number of elements emitting green light, and the number of elements emitting green light The number of elements that emit white light is the ratio that satisfies the above lower limit and upper limit and the above formulas (1) to (5). As a result, it becomes possible to irradiate the plant with the light of the spectrum peculiar to the present invention, which combines the red light emission and blue light emission necessary for photosynthesis and the green light emission that increases the amount of light absorbed into the interior of the plant leaves. Thus, it is possible to provide a plant-growing lighting device suitable for forcing cultivation of fruit vegetables and increasing the yield of fruits.

Moreover, the predetermined light-emitting elements emit light in each color at a ratio satisfying the above formulas (1) to (5), so that the mixed color light of these monochromatic lights becomes daylight-colored light with high visibility close to sunlight. This daylight light is a light quality spectrum light and high light intensity light source that leads to short-term cultivation and increased fruit yield, increasing the rate of photosynthesis and sourcing the photosynthetic products accumulated in the leaves, stems and roots. promotes partitioning and translocation to the fruit (sink).

The LED elements 12 that emit red, blue, and green light in the plurality of LED elements 12 are monochromatic light emitting elements, and the monochromatic light emitting elements emit stronger monochromatic light than when the color-tunable phosphor light emitting elements emit light in each color. can be irradiated. As a result, it is possible to irradiate the plant with light that further combines red light emission and blue light emission necessary for photosynthesis and green light emission that increases the amount of light absorbed into the interior of the plant leaves.

The use of monochromatic light emitting elements also contributes to the realization of a spectrum suitable for growing plants, especially fruit vegetables and flowering plants. A combination of monochromatic light-emitting elements of a plurality of colors has a sharper peak spectrum in the wavelength region provided by each monochromatic light-emitting element than an arrangement of the same number of white light-emitting elements. Therefore, by using a monochromatic light emitting element, a spectrum more suitable for cultivation of fruit vegetables and flowers can be realized.

Moreover, if the predetermined light emitting element is a combination of a monochromatic light emitting element and a white light emitting element, it is possible to prevent a complicated configuration including control means for adjusting the color of the light emitting element.

A case where the LED element 12 is a combination of a monochromatic light LED element and a white light LED element will be described below. A person skilled in the art who has access to the description of the present embodiment will be able to similarly configure a lighting device for growing a plant including a light-emitting element that can be adjusted in color.

In the following description, as shown in FIG. 2, the LED element 12 emitting red light is a red LED element 12R, the LED element 12 emitting blue light is a blue LED element 12B, and the LED element 12 emitting green light is a green LED element. The element 12G and the LED element 12 which emits white light generated by the combination of the blue LED element and the yellow phosphor are referred to as the white LED element 12W. The color ratio in the CIE color system (CIE RGB color space) of the light emitted by the LED lighting device 1 is 15% red (R): 79% green (G): blue regardless of the wattage of power consumption. (B) 6% to red (R) 19%: green (G) 76%: blue (B) 5.0%.

According to this embodiment, for example, an SMD5730 type chip LED is applied as the LED element 12 . This chip LED has a substantially rectangular shape with a vertical width of 5.7 mm and a horizontal width of 3.0 mm. As the LED element 12, any element having a luminous efficiency equal to or higher than 35 lumens/watt can be applied.

In the present embodiment, it is preferable that the direction in which the positive and negative terminals of the chip LED face each other and the direction in which the light-emitting elements are arranged are substantially perpendicular to each other. This eliminates the need to arrange wiring or the like between adjacent chip LEDs. Therefore, it is possible to shorten the distance between the light emitting portions of the chip LED. As a result, it is possible to realize daylight color with less color unevenness of the irradiated light.

When the LED elements 12 are mounted on the mounting portion 112 of the aluminum substrate 11, the vertically extending side surfaces of the adjacent LED elements 12, 12 are arranged to face each other, and there is no wiring between the mutually facing side surfaces. is preferred. In such an arrangement, rather than arranging the LED elements 12 in a row so that the direction in which the positive and negative terminals of the LED elements 12 face each other is along the longitudinal direction of the aluminum substrate 11, the adjacent LED elements 12 , 12 can be shortened.

As shown in FIG. 2, the LED lighting device 1 of the present embodiment includes a light-emitting portion in which a plurality of basic layouts L each having a predetermined number or less of predetermined light-emitting elements are arranged. A ratio satisfying equations (5) is achieved. Therefore, in the basic arrangement L that irradiates a range narrower than the entire range that the LED lighting device 1 irradiates, it is possible to realize the light of the spectrum peculiar to the present invention suitable for forcing cultivation of fruit vegetables.

By continuously irradiating such irradiation light with a constant amount of light for 16 hours per day without color unevenness, it is possible to appropriately irradiate light that increases the amount of photosynthesis and the rate of photosynthesis, and accelerates the growth of plants. be able to. For long-day plants and short-day plants, the irradiation time may be adjusted according to the growth characteristics of the plants.

In addition, in the configuration in which the above-described basic arrangement L is arranged, the light of the spectrum peculiar to the present invention suitable for cultivating fruits and vegetables can be realized in the basic arrangement L. It becomes unnecessary to separate the device 1 from the plant to be grown. As a result, by arranging the plant-growing lighting device closer to the plants to be grown, it is possible to improve the irradiation efficiency of the multi-stage artificial light cultivation and effectively utilize the space between the shelves.

In addition, the predetermined number described above, that is, the number of LED elements 12 in the basic layout L is limited to twelve. Although the details will be described later, the 12 LED elements 12 can realize the basic layout L that satisfies the formulas (1) to (5). Therefore, by setting the number of LED elements 12 mounted on the LED board 10 to a multiple of 12, it is possible to realize the LED board 10 that satisfies the formulas (1) to (5). By setting the predetermined number as described above, the spectral composition and light intensity of fruit vegetables and flowers are realized, and the photosynthetic rate is increased.

In this basic arrangement L, red light emitting elements are arranged at approximately the same intervals in the light emitting section, blue light emitting elements are arranged at approximately the same intervals, green light emitting elements are arranged at approximately the same intervals, and red light emitting elements are arranged at approximately the same intervals. It is preferable that the colored light emitting elements including the blue light emitting element and the green light emitting element are arranged at approximately the same intervals, and the aluminum substrate 11 is preferably wiring that can easily configure the above-described arrangement.

In the basic layout L described above, the light-emitting elements of each color are arranged at approximately the same intervals in the light-emitting section, so that color unevenness of the irradiated light can be further reduced. Moreover, according to the basic layout L described above, since the red, green, and blue monochromatic light emitting elements are arranged at approximately the same intervals in the light emitting portion, the distance between the red, green, and blue monochromatic light emitting elements The white monochromatic light emitting element is arranged in each of the leaves, and the mixed color white light that can irradiate the whole leaf uniformly can be realized.

Hereinafter, the number of light emitting elements of each color satisfies the formulas (1) to (5), and the configuration having a light emitting portion (LED substrate 10) in which a plurality of basic layouts L including 12 light emitting elements (LED elements 12) are arranged. An example will be described with reference to FIG.

The plurality of LED elements 12 are arranged on the aluminum substrate 11, a white LED element 12W, a red LED element 12R, two white LED elements 12W, a green LED element 12G, two white LED elements 12W, and two red LED elements 12R. The arrangement of the white LED elements 12W, blue LED elements 12B, and white LED elements 12W is defined as a basic arrangement L. By connecting 18 basic arrangements L, a total of 216 LED elements 12 are linearly mounted. That is, the ratio of the number of red LED elements 12R, the number of blue LED elements 12B, the number of green LED elements 12G, and the number of white LED elements 12W in the 216 LED elements 12 is 2:1:1:8.

In the above configuration, N _T =216, N _R =36, N _B =N _G =18, and N _W =144. Therefore, N _T , N _R , N _B , N _G , and N _W in the above configuration satisfy equations (1) to (5). Moreover, the above-described configuration constitutes a light-emitting portion in which 18 basic arrangements L each including 12 LED elements 12 are arranged. In the light emitting portion, the red LED element 12R, the blue LED element 12B, the green LED element 12G, and the white LED element 12W are arranged at approximately the same intervals.

Another configuration that satisfies formulas (1) to (5) is a configuration in which the number of colored light-emitting elements is increased or decreased according to the type of irradiated plant, the cultivation stage, the objective of cultivation, and the like. For example, by increasing the number of red LED elements 12R, it is expected that the light intensity will be increased and flower bud formation will be further promoted. By increasing the number of blue LED elements 12B, it can be expected that the elongation of the stalk is further suppressed and that it is suitable for artificial light type multi-stage cultivation with limited shelf height. By increasing the number of green LED elements 12G, it can be expected to further improve the light utilization efficiency. By increasing the number of white LED elements 12W, it can be expected to further increase the light intensity.

Furthermore, as another configuration that satisfies formulas (1) to (5), the number of basic arrangements L to be arranged is changed according to the type, arrangement, shape, etc. of the plants to be irradiated, and the desired size of the light emitting part is obtained. configuration.

The distance between the adjacent LED elements 12, 12, that is, the distance between the side surfaces of the LED elements 12, 12 facing each other, is preferably 1.8 to 2.8 mm. According to this embodiment, the main body size is 1150 mm (substrate is 1146 mm), the LED lighting power consumption is 18 W, and the LED lighting device 1 has 216 chips. Here, since the width of the chip LED is 3.0 mm, the interval between the adjacent LED elements 12, 12 is set to 2.0 to 2.3 mm.

In addition, in the example shown in FIGS. 1 to 3, the plurality of LED elements 12 of the LED substrate 10 are connected in parallel to the power supply device, but they may be connected in series.

Further, according to the above-described embodiment, the LED lighting device 1 has an LED main body size of 1150 mm 18 W (substrate 1146 mm) and 216 chip rows per row (red 2: green 1: blue 1: white 8 × 18), but the formula ( Any four-color RGBW LED lighting device 1 that satisfies 1) to (5) falls within the scope of the present invention. For example, LED lighting devices of Examples 1 to 4 below also belong to the scope of the present invention.
Example 1. LED body size 850mm 14W (substrate 846mm) 168 chips per row (red 2: green 1: blue 1: white 8 x 14)
Example 2. LED body size 550mm 9W (substrate 546mm) 120 chips per row (2 red: 1 green: 1 blue: 8 x 10 white)
Example 3. LED body size 1150mm 36W (board 1146mm) 432 chips in 2 rows (red 2: green 1: blue 1: white 8 x 36)
Example 4. LED body size 850 mm 28 W (board 846 mm) 336 chips in two rows (red 2: green 1: blue 1: white 8 x 28)
Example 5. LED body size 550mm 18W (substrate 546mm) 120 chips in 2 rows (red 2: green 1: blue 1: white 8 x 20)
The LED lighting device 1 with an LED main body size of 1150 mm is for a shelf plate standard size of 1200 mm. The LED lighting device 1 with an LED main body size of 850 mm is for a shelf board standard size of 900 mm. The LED lighting device 1 with an LED main body size of 550 mm is for a shelf board standard size of 600 mm.

Further, according to the above-described embodiments, SMD2835 type LED chips are used, but other LED chips may be used. For example, SMD2035 type and SMD3030 type LED chips may be used as long as they are equivalent to or greater than 35 lumens/watt.

Further, according to the above-described embodiments, the plurality of LED chips are arranged (side-by-side) so as to be aligned in the direction perpendicular to the longitudinal direction of the LED chips. It is not excluded that they are arranged (tandemly) along the longitudinal direction of the chip.

FIG. 6 is a diagram showing the emission spectrum of the LED lighting device 1. As shown in FIG. In FIG. 6, the horizontal axis is the wavelength, and the vertical axis is the relative emission intensity value. As shown in FIG. 6, the spectrum of the illumination light of the LED lighting device 1 has a first peak wavelength in the range of 440 to 460 nm, a second peak wavelength in the range of 510 to 530 nm, and a second peak wavelength in the range of 640 to 660 nm. It has a third peak wavelength, the relative emission intensities of the second and third wavelengths are substantially the same, and the first peak wavelength is approximately 1.6 times the second and third peak wavelengths. 440-460 nm corresponds to blue, 510-530 nm corresponds to green, and 640-660 nm corresponds to red. In this way, the LED lighting device 1 of the present embodiment emits light of red and blue wavelengths necessary for photosynthesis, and green wavelengths of light that drives photosynthesis in chloroplasts that have not reached light saturation inside the leaves. It becomes possible to irradiate the light of the spectrum peculiar to the present invention, which contains the ratio suitable for the growth of the seed.

FIG. 6 also shows the emission spectrum of the LED lighting device 1 in which the LED substrate 10 is mounted on the heat sink 20 without the slope portion 25 and the reflecting surface 26, and the LED substrate on which only the white LED elements are mounted. are shown together with the emission spectrum of the LED lighting device.

As shown in FIG. 6, the light emitted by the LED board 10 using the red, green, blue, and white LED elements 12 has a wavelength of about 660 nm, compared to the light emitted by the LED board on which only the white LED elements are mounted. , that is, the amount of light in the red wavelength region is large. Further, comparing the case with and without the reflecting surface 26, the peak wavelengths are almost the same, but the emission intensity is higher with the reflecting surface 26. FIG. In this way, by using the red, green, blue, and white LED elements 12, the red and blue wavelengths necessary for photosynthesis and the green wavelength light that increases the light utilization efficiency of plants can be used to grow fruit vegetables and flowering plants. It is possible to irradiate light of the spectrum peculiar to the invention, containing in suitable proportions. Moreover, by having the reflective surface 26, it becomes possible to increase the amount of light irradiated to the plant without increasing the power consumption of the LED element 12 for light emission. Therefore, it is possible to improve efficiency and save power as a lighting fixture.

In addition, the LED lighting device 1 has the red, green, blue, and white LED elements 12 arranged as described above, so that the emitted light color is a daylight color (color rendering Ra 95) close to that of sunlight. As a result, it becomes possible to increase the speed of plant growth and improve the visibility of plants by workers in the artificial light type plant factory. In addition, the LED lighting device 1 can reduce color unevenness of the irradiated light by providing regularity to the arrangement of the LED elements 12 . According to this embodiment, even when the object was irradiated with light from a distance of about 15 to 20 cm, no color unevenness was observed in the irradiated light.

In addition, although the details will be described later, in practice, from the seeding of tomatoes, three LED lighting devices 1 of the present embodiment are used per shelf, and light is emitted per day under a constant temperature, humidity, and carbon dioxide concentration. When LED light cultivation was carried out while irradiating for 16 hours, the cultivation period until ripening of the fruit could be shortened to about 70 to 74 days. Here, it was found that the tomato seeds sown in the test cultivation can bear fruit about 30% faster than the others, because it takes 100 days to bear fruit when cultivated in a greenhouse under sunlight. In addition, when the LED lighting device 1 of the present embodiment is used, the ratio of the number of tomato seeds attached to the first flower cluster is 10 to 20 compared to the conventional case, compared to the case of using the LED lighting device that emits only white light. % was found to be higher.

The spectrum of the light emitted by the LED lighting device 1 of this embodiment corresponds to a color temperature of 6500 Kelvin and a color rendering Ra of 95, and has peaks corresponding to red, blue, and green. By providing monochromatic light-emitting elements corresponding to red, blue, and green, respectively, the spectrum is similar to the spectrum of a conventional lighting device for growing plants, even in the sharpness of the peaks corresponding to each color, especially the peaks corresponding to green and red. different from As a result, the photosynthetic rate, photosynthetic products, and flower bud formation of tomatoes, which are fruit vegetables, can be further increased. The first inflorescence growing leaf position is between the eighth and ninth leaves in greenhouse horticulture. It is considered that the period and yield were greatly improved.

Next, a cultivation test using the LED lighting device 1 of this embodiment will be described.

[Test method and conditions]
The plants selected for the cultivation test were a dwarf low-stage cherry tomato that can be cultivated under artificial light and a seed-propagating strawberry "Yotsuboshi". This is because the conventional closed-type plant factories mainly produce leafy vegetables such as lettuce, and there are few plant factories capable of harvesting fruit vegetables such as strawberries and tomatoes. The reason for this is that the cultivation period from sowing to harvesting is longer than that of leafy vegetables. In addition, it requires more light than leafy vegetables and consumes more electricity, so it is not cost-effective.

Therefore, a cultivation test was conducted under the following conditions for the purpose of shortening the cultivation period of fruit vegetables and finding the optimum spectrum of fruit vegetables.

First, a 25 mm square germination sponge seeded with dwarf low-stage cherry tomatoes and a 25 mm square germination sponge seeded with dwarf low-stage cherry tomatoes are prepared. The seeded germination sponges are placed on a cultivation shelf.

Two types of cultivation racks, 20 cm in height and 40 cm in height, are prepared. A cultivation rack with a height of 20 cm is used during the growth period from germination to a plant height of 15 cm, and a cultivation rack with a height of 40 cm is used during the growth period from a plant height of 15 cm to a plant height of 25 cm.

An LED lighting device is arranged on the top surface of the cultivation shelf. It is assumed that there are three LED lighting devices per shelf. The lighting time by the LED lighting device per day is assumed to be 16 hours.

The following four types of LED lighting devices were prepared.
(1) White high-brightness LED lighting, no reflector (hereinafter referred to as white light source lighting without reflector)
168 chips of high-brightness white LED elements of element size SMD2035 are mounted in a row, power consumption 18W, lumen value 2800LM, color rendering RA82, color temperature 5000K
(2) White high-brightness LED lighting with reflector (hereinafter referred to as lighting with white light source and reflector)
168 chips of SMD2035 type high-brightness white LED elements are mounted in a horizontal row, power consumption is 18W, lumen value is 3050LM, color rendering is RA82, color temperature is 5000K.
(3) RGBW four-color mixed light source white LED lighting without reflector (hereinafter referred to as four-color mixed light without reflector)
Device size SMD2835, red, green, blue, and white LED devices and 216 high-brightness white LED devices mounted in a vertical row, power consumption 18W, lumen value 2300LM, color rendering RA95, color temperature 6100K
(4) RGBW four-color mixed light source white LED lighting with reflector (hereinafter referred to as lighting with four-color mixed light reflector)
Device size SMD 2835 type, red, green, blue, and white LED devices and 216 high-brightness white LED devices mounted in a vertical row, power consumption 18W, lumen value 2600LM, color rendering RA95, color temperature 6200K

Among the four types of LED lighting devices described above, lighting with four types of mixed-color light reflectors corresponds to the LED lighting device 1 of the present embodiment.

FIG. 7 is a diagram showing the distribution of light on the surface of a cultivation shelf. The numerical values shown in FIG. 7 are photosynthetic photon flux densities (hereinafter referred to as PPFD values). Photosynthetically effective photon flux density is the number of photons per unit time and unit area contained in the wavelength of 400 to 700 nm required for photosynthesis. (chlorophyll and carotenoids) and is used as a measure of light intensity. The unit of the PPFD value is μmol·m ⁻² ·s ⁻¹ . As shown in FIG. 7, the amount of light is the highest in the lighting with the 4-type mixed-color light reflector, followed by the lighting with the white light source reflector, the lighting without the 4-type mixed-color light reflector, and the lighting without the white light source reflector in descending order. I know it will be. That is, it can be seen that the amount of light is supplemented by the reflector (reflecting surface 26).

Then, under the environment shown in FIG. 7, a 25 mm square germination sponge seeded with dwarf low-stage cherry tomatoes and a 25 mm square germination sponge seeded with seed-propagating strawberry "Yotsuboshi" were placed, A growth test was performed.

[Test results of dwarf low-stage mini tomatoes]
From seeding to germination, no difference was observed under the four types of LED lighting, and 90% or more of the seeds germinated within one week.

・Vegetative growth period (from sowing to flowering)
(Lighting without white light source reflector)
On the 40th day after germination, the first inflorescence on the leaf of the eighth leaf has two buds and one flower, and the stem between the leaves is slightly elongated and the stem is thin.
(Lighting with white light source reflector)
40 days after germination, 4 buds and 2 flowers in the first inflorescence on the leaf of the 8th leaf. The leaf area is larger than the lighting without the white light source reflector, but the same as the lighting without the white light source reflector. The stem between the leaves is elongated, and the stem is a little thick.
(Lighting without a 4-color mixed light reflector)
35 days after germination, 2 buds and 1 flower in the 1st inflorescence on the 6th leaf, with a white light source reflector. Short, slightly thick stems and good stock.
(Lighting with a 4-color mixed light reflector)
35 days after germination, 4 buds and 2 flowers in the 1st inflorescence on the 6th leaf, with a white light source reflector. Short, slightly thick stems and good stock.

・Reproductive growth period (flowering-fruiting-harvesting)
(Lighting without white light source reflector)
On the 50th day after germination, two flowering flowers and one fruiting appear in the first inflorescence, and the stem between the leaves is slightly elongated and thin.
On the 60th day after germination, 2 buds and 3 flowers were formed in the 2nd inflorescence on the 11th leaf, the stem between the leaves was slightly elongated, and part of the leaves turned yellow.
Three fruits were harvested from the first inflorescence on the 80th day after germination. The second flower cluster has 5 fruits. Deciduous until the second leaf.
(Lighting with white light source reflector)
On the 50th day after germination, 4 flowers and 2 fruits were formed in the first inflorescence, and the stem between the leaves was slightly elongated and thickened.
60 days after germination, 6 buds and 4 flowering clusters on the 2nd inflorescence on the 11th leaf, the stem between the leaves elongated, and the 3rd inflorescence on the 14th leaf, 8 Individual buds formed.
Six fruits were harvested from the first inflorescence on the 80th day after germination. The second flower cluster is rather small and produces 10 fruits. The 3rd flower cluster is small and bears 8 fruits. Deciduous until the second leaf.

(Lighting without a 4-color mixed light reflector)
On the 45th day after germination, two flowering flowers and one fruiting appear in the first inflorescence.
On the 55th day after germination, 6 buds and 4 flowering clusters were formed on the 2nd inflorescence on the 9th leaf, the stem between the leaves was elongated, and 8 3rd inflorescences were formed on the 12th leaf. Individual buds formed.
Three fruits were harvested from the first inflorescence on the 75th day after germination. The second flower cluster produces 10 fruits. The third inflorescence bears 8 fruits.
(Lighting with a 4-color mixed light reflector)
On the 45th day after germination, 4 flowers and 2 fruits were formed in the first inflorescence, and the stem between the leaves was slightly elongated and thick.
On the 55th day after germination, 6 buds and 4 flowers bloomed in the second inflorescence on the 9th leaf, the stem between the leaves elongated, and the 3rd inflorescence appeared on the 12th leaf. Form 8 pieces.
Six fruits were harvested from the first inflorescence on the 75th day after germination. In the second flower cluster, 10 slightly smaller fruits are produced. 8 fruiting in the third flower cluster.

[Discussion]
(About growth)
As for the lighting without a white light source reflector, the leaves are slightly thin in the vegetative growth period, but the growth is smooth.
It blooms during the reproductive growth period, but the fruits that bear fruit tend to drop before maturity. The number of harvests is small and the fruit is small with a diameter of around 20 mm. The leaves also turn yellow, and the leaf surface is slightly green.
As for the lighting with a white light source reflector, the leaves grow vigorously in the vegetative growth period, but the stems are rather thin and elongated. In the reproductive growth period, the fruit of the first inflorescence is large and has a diameter of about 25 to 30 mm, while the fruit of the second inflorescence is as small as 15 to 20 mm in diameter.
The leaves grow vigorously during the vegetative growth period under lighting without a four-color mixed light reflector. The stem is rather thin, but the leaves are wide. In the reproductive growth period, the fruit of the first inflorescence is large and has a diameter of about 30 mm, while the fruit of the second inflorescence is rather small, 20-25 mm in diameter.
The leaves grow vigorously during the vegetative growth period in the case of lighting with a four-color mixed light reflector. Stems are thick and leaves are wide. In the reproductive growth period, the fruit of the first inflorescence is large and has a diameter of about 30 mm, while the fruit of the second inflorescence is slightly smaller with a diameter of 20-25 mm. Higher yield than other lights.
(Regarding yield (weight basis))
Lighting with 4-type mixed-color light reflector > Lighting without 4-type mixed-color light reflector > Lighting with white light source reflector > Lighting without white light source reflector.
In the case of white light source LED irradiation, the green color of the leaf surface is pale and the leaves are somewhat thin, and the formation of photosynthetic products seems to be slightly inferior to the growth under sunlight, and the flower bud formation is smooth. Fruits tend to drop before they reach maturity.
In the case of 4-color mixed light LED irradiation, the leaf surface of the first and second leaves is dark green, the leaves are wide, there is a leaf area (high light receiving rate), and sufficient photosynthetic products are formed. Seem.

[Test results of seed-propagated strawberry “Yotsuboshi”]
There are individual differences from sowing to germination, and since it takes 1 to 2 weeks from sowing to germination and there are differences in growth, the cultivation start date was set at the time when true leaves appeared.

・ Vegetative growth period (true leaf to runner formation)
(Lighting without white light source reflector)
No growth, leaves turn white and die.
(Lighting with white light source reflector)
Sixty days after the emergence of true leaves, two runners appeared, and 10 to 11 leaves.
There are individual differences, and some individuals have been discontinued due to the appearance of chlorosis on the leaf surface, the green color of the leaf surface is pale, and the growth slows down.
(Lighting without a 4-color mixed light reflector)
On the 60th day from the emergence of true leaves, two runners appeared and 10 leaves. 20 g of plant weight (including the weight of a 25 mm square medium sponge).
(Lighting with a 4-color mixed light reflector)
On the 60th day from the emergence of true leaves, two runners appeared and 11 leaves. Plant weight 22.5 g (including the weight of a 25 mm square medium sponge). The leaf surface is larger than the leaf surface under illumination without the 4-color mixed light reflector.

Strawberry 'Yotsuboshi' is a seed-propagating strawberry, and has long day life. For this reason, the strawberry "Yotsuboshi" did not form fruit in the main cultivation test. However, it can be easily inferred from the experimental results up to this point that the harvested amount is not less in the case of illumination with four kinds of mixed-color light than in the case of illumination with white light source. In addition, in the comparative tests so far, since the irradiation time per day was fixed at 16 hours, flower bud formation became leaf bud formation and runners appeared. Flowering induction technology in artificial light cultivation of strawberries (seed propagation system) is advanced, and detailed description is omitted, but the change in irradiation time and temperature, carbon dioxide concentration, and flower bud formation suitable for LED lighting of the present invention Based on past test results, it is expected that fruits will be harvested around 110 to 120 days after sowing if environmental control is carried out by changing fertilizer components.

[Discussion]
The above-mentioned cultivation test of the strawberry “Yotsuboshi” is in progress, but the cultivation tests conducted so far have shown that LED lighting with four types of mixed-color light reflectors is preferred over LED lighting with white light source reflectors. It turns out that you have an advantage. In addition to cultivation for the purpose of fruit harvesting, lighting with a four-kind mixed-color light reflector can be applied to a seedling production and cultivation apparatus as a use for producing seedlings for facility gardening greenhouse cultivation. In greenhouse cultivation, it takes about 3 months from sowing to planting seedlings (crown 8 mm or more), but if LED lighting equipment with 4 types of mixed color light reflectors is used, it takes about 70 days from sowing to planting seedlings. Stable production can be achieved by raising seedlings, and the cultivation period can be shortened by around 20 days compared to the raising period of seedlings in a greenhouse. Furthermore, raising seedlings in greenhouse cultivation requires spraying pesticides several times. No pesticides occur, and the frequency of pesticide spraying can be reduced. It is presumed that the reason why disease does not occur is that photosynthesis is carried out in a healthy manner, resulting in resistance to disease (disease resistance).

FIG. 8 is a photograph showing the growth of the seed-propagated strawberry "Yotsuboshi" in cultivation tests using four types of LED lighting devices. FIG. 9 is a photograph showing the growth of dwarf low-row cherry tomatoes in a cultivation test using four types of LED lighting devices. FIG. 10 is a photograph showing the state of growth of dwarf low-stage cherry tomatoes nine days after the photographing of FIG. 9 was performed. 8 to 10, from left to right, illumination without a white light source reflector, illumination with a white light source reflector, illumination without a four-color reflector, and illumination with a four-color reflector are arranged in this order. As shown in FIGS. 8 to 10, it is clear that the seedlings using four kinds of mixed-color LEDs are growing well.

Until now, fruit vegetables such as strawberries and tomatoes or flowering plants require a light amount of 300 to 350 μmol・m ⁻²・s ⁻¹ of PPFD value, but if cultivated with lighting with a 4-color mixed light reflector, 200 to 200 Cultivation is possible with a value of 300. This requires a strong light intensity to reach the light saturation point of all the chloroplasts, but by adding green light, the spectrum light with good absorption and the irradiation light with good absorption are uniformly irradiated without color unevenness. It is thought that most of the chloroplasts in the entire leaf have reached the light saturation point. In FIG. 7, even if the PPFD values are the same, the growth rate varies depending on the light quality of the spectrum light, as in the case of the illumination with the white light source reflector and the illumination with the four mixed color light reflectors. It can be seen that there is a big difference.

In particular, as a result of a cultivation test of dwarf low-stage cherry tomatoes, it can be seen that the light quality of either red light or green light affects the expansion of the leaf area of the first and second leaves in tomatoes. When comparing the appearance of the plant in the stage just before flowering of the first inflorescence, the first leaf and the second leaf show the leaf area when the plant is irradiated with the mixed color light of the present invention and when the plant is irradiated with the white monochromatic light. deployment is different. In the plant body irradiated with the mixed color light of the present invention, the first and second leaves have expanded leaf areas. There remains little expansion. Or there is an individual that sheds leaves. Also, looking at the stalk enlargement, the average diameter of the stem of the plant irradiated with the four kinds of mixed light of the present invention is about 7 mm, while the average diameter of the stem of the plant irradiated with the white monochromatic light is about 7 mm. was about 5.5 mm. This is because the light intensity of the red light and the green light is higher in the mixed four-color light of the present invention than in the white monochromatic light, and the first and second leaves are shadowed by the third to sixth leaves. In order to emit light straight in one direction, which is the characteristic of light, red and blue light are absorbed by the 3rd to 6th leaves, which are positive leaves, and green light that is not absorbed by the 3rd to 6th leaves is emitted. It is considered that the absorption by the first and second leaves, which serve as shade leaves, led to the expansion of the leaf area. In other words, it can be said that the expansion of the leaf area increases the light receiving rate, and the photosynthetic products stored in the leaves and stems increase through photosynthesis.

[Effect]
According to the present embodiment configured as described above, the ratio of the number of red LED elements 12R, the number of blue LED elements 12B, the number of green LED elements 12G, and the number of white LED elements 12W is given by formula (1) or (5), red light emission and blue light emission necessary for photosynthesis, green light emission that increases the light utilization efficiency of plants, and white light that supplements the light intensity of these monochromatic lights are used to grow fruits and vegetables. It becomes possible to irradiate the plants with the light of the spectrum peculiar to the present invention, which is included in a ratio suitable for , and it is possible to perform lighting suitable for cultivating fruit vegetables exemplified by tomatoes and strawberries. Moreover, the ratio of the number of red LED elements 12R, the number of blue LED elements 12B, the number of green LED elements 12G, and the number of white LED elements 12W satisfies the formulas (1) to (5). It is possible to provide the LED lighting device 1 that emits light in a daylight color that can be maximized. Moreover, by using the LED element 12, power saving can be achieved.

Further, according to this embodiment, the LED substrate 10 has a basic arrangement L of two red LED elements 12R, one blue LED element 12B, one green LED element 12G, and eight white LED elements 12W. Since it is a multiple-repeating arrangement, it is possible to realize a mixed light color that is close to sunlight and is uniform. By irradiating light uniformly in this way, photosynthesis can be promoted, and the growth of plants can be promoted.

Here, according to this embodiment, the white LED element 12W is used, but instead of using the white LED element 12W, the mixed light of the red LED element 12R, blue LED element 12B, and green LED element 12G produces white light. can be formed. However, the light intensity of the white light produced by these monochromatic lights of red, green, and blue is insufficient. That is, in an LED lighting device with a theoretical power consumption of 18 W and 216 chips, when the 216 chips are red, green, and blue chips, the total lumen value is about 400 lumens. The total lumen value for the white chip is about 2500 lumens, and the light intensity of the latter is higher. Thus, according to the present embodiment, by adding the white LED element 12W, it is possible to compensate for the lack of light intensity.

Further, according to this embodiment, the basic arrangement L consists of a red LED element 12R, two white LED elements 12W, a green LED element 12G, two white LED elements 12W, a red LED element 12R, and two white LED elements. 12W and blue LED elements 12B. As a result, in the basic layout L, it is possible to realize a uniform daylight color in which the photosynthesis of plants can be maximized.

Further, according to this embodiment, the LED element 12 is a chip LED, and the LED element 12 has the direction in which the anode terminal and the cathode terminal face each other, that is, the longitudinal direction of the chip LED with respect to the longitudinal direction of the aluminum substrate 11 . Since the chip LEDs are arranged in the direction perpendicular to each other, it is possible to shorten the distance between the light emitting portions of the chip LED. As a result, in the basic arrangement L, a uniform daylight light source can be realized in which the photosynthesis of plants can be maximized.

Further, according to this embodiment, two or more reflecting surfaces 26 are provided that can reflect at least part of the light emitted from the LED element 12 in a direction different from the direction toward the plant to be grown, toward the plant to be grown. As a result, of the light emitted by the plurality of LED elements 12, the light directed not toward the plant from the LED elements 12 (for example, oblique light) can be reflected and irradiated to the plant to be grown. Thus, it is possible to efficiently irradiate the plant to be grown while maintaining the amount of light generated by the plurality of LED elements 12 . Therefore, it is possible to increase the amount of light applied to the plant to be grown without increasing the power consumption of light emitted by the LED element 12 . Therefore, by providing the reflective surface 26, it becomes possible to improve efficiency and save power as a lighting fixture.

Further, according to this embodiment, as shown in FIG. 7, by providing the reflecting surfaces 26 on both sides of the storage portion 24 in the heat sink 20, the scattered light from the LED elements is reflected and irradiated to the plant to be grown. Therefore, it is possible to irradiate light more efficiently. Alternatively, the LED substrate 10 may be directed toward the reflecting surface 26 so that the plant to be grown is irradiated with the light reflected by the reflecting surface 26 .

[Modification]
Although one embodiment of the present invention has been described above, the embodiment of the present invention is not limited to the above-described embodiment.

For example, in the embodiment described above, the plurality of LED elements 12 are arranged in one row, but as shown in FIG. 11, two LED substrates 10 may be arranged to arrange the plurality of LED elements 12 in two or more rows. By providing two or more rows of the LED elements 12 in this way, it is possible to increase the amount of light that irradiates the plants, and it is possible to improve efficiency and save power as a lighting fixture. In addition, by providing two or more rows, when the shelf height in multi-shelf cultivation is increased in proportion to the elongation of the plant body, it is possible to eliminate the lack of light intensity on the leaves near the base of the plant. For example, in the case of dwarf cherry tomatoes, the plant height at the first inflorescence epiphytic leaf position is about 20 cm, and the second inflorescence epiphytic leaf position is about ^{30 cm} . To maintain this, it is desirable to increase the number of installed LED lighting devices 1 or to provide the LED lighting device 1 with two or more rows of LED elements 12 . In the example shown in FIG. 11, two LED substrates 10 are arranged to form two rows of LED elements 12. However, as shown in FIG. may

FIG. 12 is an explanatory diagram showing a mode in which two rows of a plurality of LED elements 12 are mounted on one aluminum substrate 11 in a modification. In the aluminum substrate 11 shown in FIG. 12, the same members or members having the same functions as those of the aluminum substrate 11 shown in FIG.

The aluminum substrate 11 shown in FIG. 12 further includes a rectangular wiring portion 111f. The wiring portion 111f is not connected to the wiring portion 111a and the wiring portion 111b. The width of the aluminum substrate 11 shown in FIG. 12 is larger than that of the aluminum substrate 11 shown in FIG. 5, and the distance between the wiring portion 111a and the wiring portion 111b is widened. In addition, in the wiring portion 111c of the aluminum substrate 11 shown in FIG. 12, the wiring extending along the lengthwise direction of the wiring portion 111a is elongated in the central portion extending in the direction perpendicular to the lengthwise direction of the wiring portion 111a. The distance between one end and the other end of the portion 111c is widened, with one end facing the wiring portion 111b and the other end facing the wiring portion 111a.

A first wiring portion 111f is arranged between the extending portion 111d and one end of the first wiring portion 111c. A wiring portion 111f is arranged between the other end of the first wiring portion 111c and one end of the second wiring portion 111c. Similarly, the wiring portion 111f is arranged between the other end of the wiring portion 111c and one end of the next wiring portion 111c, and the wiring portion 111f is arranged between the other end of the 23rd wiring portion 111c and the extending portion 111e. A 24th wiring portion 111f is arranged. In this manner, 24 wiring portions 111f are arranged in a row for one basic layout L between the wiring portions 111a and 111b. Thus, the mounting portion 112 is formed by the extending portion 111d and the first wiring portion 111f, and the mounting portion 112 is formed by the first wiring portion 111f and one end portion of the first wiring portion 111c. The mounting portion 112 is formed by the other end of the first wiring portion 111c and the second wiring portion 111f, and the mounting portion 112 is formed by the second wiring portion 111f and one end of the second wiring portion 111c. be done. Similarly, the mounting portion 112 is formed by the other end portion of the N-1th (N is a natural number of 3 or more and 23 or less) wiring portion 111c and the Nth wiring portion 111f. The mounting portion 112 is formed with one end portion of the second wiring portion 111c. Finally, the mounting portion 112 is formed by the other end portion of the 23rd wiring portion 111c and the 24th wiring portion 111f, and the mounting portion 112 is formed by the 24th wiring portion 111f and the extension portion 111e.

Thus, two mounting portions 112 are formed side by side for one wiring portion 111f, and two rows of mounting portions 112 are formed on the aluminum substrate 11 by arranging the wiring portions 111f in a row. By mounting the LED elements 12 on each of the two rows of mounting portions 112, 48 LED elements 12 can be connected in series in one basic layout L, and can be connected in parallel in units of the basic layout L. .

In the above-described embodiment, the red, blue, green, and white LED elements 12 are arranged in a row. Alternatively, both LED elements may be included. Alternatively, ultraviolet light LED elements or far-infrared light LED elements that can be turned on and off may be provided at arbitrary positions other than the rows of the red, blue, green, and white LED elements 12 on the aluminum substrate 11 .

In the ultraviolet light LED element, the light emission time of the ultraviolet light LED element may be controlled only during a period when people are not engaged in cultivation work. As a result, it is possible to irradiate ultraviolet rays to an extent that does not adversely affect plants, and to kill disease-causing fungi, viruses, or insect eggs adhering to plants. Therefore, it is possible to cultivate pest-free seedlings without using pesticides in an artificial light plant factory or an artificial light type seedling production apparatus.

In addition, pollination work in strawberry cultivation in a plant factory can be performed manually using a brush. However, manual work using a brush tends to produce malformed fruits, so it is desirable to use pollinating insects for pollination in order to improve quality. Here, pollinating insects such as honeybees and bumblebees are known to move actively under near-ultraviolet rays. Therefore, near-ultraviolet irradiation is desirable at the flowering stage of strawberries. As a result, the pollinating insects move actively in the environment illuminated by the LED lighting device 1, and pollination work can be efficiently performed.

By the way, the illumination by the LED lighting device 1 shown in FIG. 1 is mainly illumination in the visible light range, and the illumination in the visible light range contributes to promotion of photosynthesis which is a factor in plant growth. However, the photoresponse of plants includes photomorphogenesis in addition to photosynthesis. Photomorphogenesis includes near-ultraviolet light and far-infrared light in addition to the light quality in the visible light range and the light quality in the visible light range. In artificial light plant cultivation with light quality in the visible light range, the leaves and stems of the plant tend to become smaller. This is because it does not contain far-infrared light.

In general, in the far infrared rays in photosynthesis for growth, the elongation of leaves and stems that affect the shape of plants is divided into two wavelength ranges centered on 660 nm (red light: R) and 730 nm (far red light: FR). There is a close relationship with the included photon flux ratio (R/FR ratio), and when this value is large, the leaf area and stem height tend to be small. As described above, an increase in leaf area (light receiving rate) is required for photosynthesis of a plant body. In order to increase the rate of photosynthesis and increase the light-receiving rate for the accumulation of photosynthetic products in fruits and vegetables, it is expected to increase the leaf area and promote stem elongation by irradiating far-infrared light and reducing the value of the photon flux ratio. be done. This photomorphogenesis has the effect of utilizing near-ultraviolet rays. For example, the coloration of strawberry fruits is slightly inferior in light quality in the visible light region, but the coloration of the fruits can be made vivid by irradiating near-ultraviolet light during the ripening stage. Similarly, in leaf lettuce, the tips of the leaves can be colored brown by irradiating them with near-ultraviolet rays just before harvesting.

Further, in the embodiment of the present invention, it is assumed that the LED lighting device 1 is used indoors such as a plant factory, but the use of the LED lighting device 1 outdoors is not excluded. For example, in greenhouse horticulture, in order to solve the lack of sunlight due to bad weather and to adjust the flowering of long-day plants, the LED lighting device 1 is irradiated to supplement the light irradiated to fruit vegetables such as strawberries and flowering plants such as chrysanthemums. is also possible.

It should be noted that within the scope of the idea of the present invention, those skilled in the art can conceive of various modifications and modifications, and it is understood that these modifications and modifications also fall within the scope of the present invention. For example, additions, deletions, or design changes of components, or additions, omissions, or changes in conditions of the above-described embodiments by those skilled in the art are also included in the gist of the present invention. is included in the scope of the present invention as long as it has

1 LED lighting device 10 LED substrate 11 aluminum substrates 111, 111a, 111b wiring portion 112 mounting portion 12 LED element 12B blue LED element 12G green LED element 12R red LED element 12W white LED element 20 heat sink 24 storage portion 25 slope portion 26 reflective surface L basic layout

Claims (7)

Equipped with a plurality of light emitting elements,
Among the light emitting elements, among the light emitting elements _, the number of the predetermined light emitting elements that irradiate the plant to be grown is N _T , the number of the predetermined light emitting elements that can emit red light, the number of the predetermined light emitting elements that can emit blue light, and the predetermined light emitting elements that emit blue light. The number of elements capable of emitting light N _B , the number of elements capable of emitting green light among the predetermined light emitting elements N _G , and the number of elements capable of emitting white light among the predetermined light emitting elements N _W A lighting device for growing plants for fruits and vegetables, which satisfies (5).
N _T = N _R + N _B + N _G + N _W (1)
28/216≦N _R /N _T ≦44/216 (2)
14/216≦N _B /N _T ≦22/216 (3)
14/216≦ _NG / _NT ≦22/216 (4)
128/216≦N _W /N _T ≦160/216 (5) The element capable of emitting red light is a red light emitting element,
The device capable of emitting blue light is a blue light emitting device,
The device capable of emitting green light is a green light emitting device,
The device capable of emitting white light is a white light emitting device,
The plant-growing lighting device according to claim 1 . 3. The plant-growing lighting device according to claim 2, comprising a light-emitting portion in which a plurality of basic arrangements having 12 predetermined light-emitting elements are arranged. The basic arrangement is, in the light emitting unit,
The red light emitting elements are arranged at approximately the same intervals,
The blue light emitting elements are arranged at substantially the same intervals,
The green light emitting elements are arranged at substantially the same intervals,
Colored light emitting elements including the red light emitting element, the blue light emitting element, and the green light emitting element are arranged at substantially the same intervals,
is a configurable arrangement,
4. The lighting device for growing plants according to claim 3. 2. The plant growing lighting according to claim 1, further comprising two or more reflectors capable of reflecting at least part of the light emitted from said light emitting element in a direction different from the direction toward said plant to be grown, toward said plant to be grown. Device. At least some or all of the plurality of light emitting elements are linearly arranged, and each of the linearly arranged light emitting elements is composed of chip LEDs having substantially the same shape and a substantially rectangular parallelepiped shape, and is linearly arranged. 2. The plant-growing lighting device according to claim 1, wherein, in each of said light emitting elements, the direction in which both positive and negative terminals of said chip LED face each other is substantially orthogonal to the direction in which said light emitting elements are arranged. 2. The lighting device for growing fruits and vegetables according to claim 1, further comprising at least one of an ultraviolet light LED element and a far infrared light LED element.

Images