JPH09252651A - Led light source for plant cultivation and individual led light source mounting type plant culture container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-weight LED light source for plant cultivation capable of simplifying a structure and being utilized for seedling production and the proliferation of adventitious embryos constituted so as to provide a light emitting diode element and be mountable to the upper part of a plant culture container. SOLUTION: This LED light source is provided with the light emitting diode elements such as the elements of red LEDs whose wavelength area is 630-680mm or the red LEDs and blue LEDs whose wavelength area is 380-480mm or the like composed by being arrayed on a base plate and is made mountable to the upper part of the plant culture container 20. Also, the plant culture container 20 is obtained from a container main body constituted of a frame 13 and an air permeable transparent resin film 14 containing a culture medium inside and a cover provided with rubber packing and a fixing means to the container main body for mounting the LED light source for the plant cultivation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a completely new type of cultivation (cultivation) container that is inexpensive and simple, and is intended for use in plant cultivation and plant tissue cultivation with an artificial light source. The cultivation (cultivation) container according to the present invention can be used in plant cultivation and plant tissue cultivation in agriculture and agriculture, bio-experiment in medicine, pharmacy, biochemistry, food science and the like. In addition, it can be applied to home gardens, table gardens, and even interiors, and is full of new business potential as consumer products (consumer products). As the advanced use of the present invention,
Cultivation of food crops in the space station is possible.

[0002]

2. Description of the Related Art Cultivation using transparent containers has been widely used for plant tissue culture, etc., but micropropagation (mass growth of cloned seedlings of elite individuals in tissue culture) does not cause contamination of bacteria in the container. It has been a problem that it has a fatal effect on the growth of shoots. In order to solve this, Michio Tanaka, who is one of the inventors of the present invention, has studied the inside of the incubator and rock wool for hydroponics (fibrous support made from sludge produced in the case of pyroxene or ironmaking). ) Was heat-pressed and sealed with a transparent fluorine-melted resin transparent film, and a practical incubator was developed.
(Japanese Patent Application No. 63-36396). After that, Michio Tanaka and Bio-U of Zentsuji City, Kagawa Prefecture remodeled this incubator and reinforced the whole with a plastic frame and separated the lid part and the main body, and foamed silicone packing and a fixed lever for both. We have developed a new type incubator that can be attached and detached quickly and easily. The new type incubator has not yet been widely used at this time, but Michio Tanaka tried to carry out micropropagation of orchid seedlings and other horticultural plants using this, and has already succeeded in the experiment. As a result, the new type incubator is currently receiving attention from industry and academic societies in Japan and overseas. Currently, Bio-U uses a fluorescent lamp for plant growth as an artificial light source for this new-type incubator, and is pioneering mass cultivation of orchid seedlings.

[0003]

Micropropagation using a new-type incubator is a revolutionary cultivation method, but this method has the following problems conventionally. (1) A fluorescent lamp for growing plants is used as a light source. This lamp has better power efficiency and less heat generation than filament type lamps, but it has a large light source, heat generation of the lamp tube itself, and a ballast (coil with core) required for each lamp on the electric circuit. The heat generated is not small, and requires considerable power for air conditioning along with the growing cultivation space. Also, in a fluorescent lamp, light is emitted in all directions perpendicular to the lamp axis, so the efficiency of irradiating the cultivation (culture) directly below it is poor, and the light irradiation intensity is the square of the distance from the lamp. Weakens in inverse proportion to. Therefore, the overall light utilization efficiency of the fluorescent lamp is not so good in practice.

(2) A plant growing fluorescent lamp is designed to radiate more light wavelength components (especially blue region and red region) necessary for plant growing than ordinary white fluorescent lamps and daylight fluorescent lamps. However, there are many light components that do not contribute much to plant growth. (3) Since the containers are placed on the fences and illuminated by the fluorescent lamps placed on the ceiling of each fence, the containers cannot be placed on top of each other. Therefore, the utilization efficiency of the cultivation space is poor.

(4) The life of the fluorescent lamp is about several thousand hours, and it is difficult to keep the light illuminance constant for a long period of time. Further, maintenance and management such as replacement of a huge number of fluorescent lamps are difficult and costly. (5) It is difficult to freely control the radiant intensity of the lamp in an ordinary fluorescent lamp circuit.

[0006]

The present inventors have succeeded in solving such a problem by mounting a light source composed of a light emitting diode in a container. That is, the present invention has an LED light source for plant cultivation, which has a light emitting diode (hereinafter abbreviated as LED) element and is configured to be mounted on a lid of a plant culture container,
And an individual LED light source mounting type plant culture container in which a light source composed of a light emitting diode (hereinafter abbreviated as an LED) is mounted on the lid part.

The present invention will be described below. The culture container of the present invention comprises a container body and a lid. The material of the container is not particularly limited, and various materials such as glass and plastic used for this kind of container can be used, but the container body is at least partially formed of a breathable material, It must have a structure to ensure breathability. The size and shape of the container are not particularly limited as long as they are convenient to handle. Preferred is a container in which a resin film having light transparency, moisture retention, durability / chemical resistance, and high gas permeability is used as a material for a part or the whole of the container. If a film is used for the entire container, it should be reinforced with a frame made of plastic, wood, metal, etc.

The red LED used in the light source has a wavelength range of 630 nm to 680 nm, preferably an emission peak wavelength of about 660 nm, and the blue LED has a wavelength range of 380 nm to 480 nm, preferably an emission peak wavelength of about 450 nm. To be The blue LED is used so that the light amount thereof is 50% or less of that of the red LED. The LEDs use a mixture of red and blue, but depending on the plant, red alone may be used. The LED light source may be mounted inside the lid, or may be mounted on the lid formed of a light-transmissive material so as to overlap. It is also possible to use the light source composed of the substrate on which the LED element is arranged as it is as the lid of the container. It is preferable that the lid and the main body are independent from each other, and can be easily sealed and connected and separated by, for example, rubber packing and a fixed lever. By making the lid and the container body independent, the container other than the light source part can be easily heated and sterilized. In addition, if necessary, in order to avoid mixing of various bacteria in the container, it is preferable to cover the opening of the container body with a light-transmitting material such as a resin film. A culture medium and a culture solution are contained in the culture container. Preferred embodiments will be described below.

1. Light source A light emitting diode (Light Emitting Diode, commonly known as L) is used as a light emission source essential for plant growth.
ED, hereinafter referred to as LED), particularly, the latest ultra-bright LED that emits bright light with a dazzling current at a current of only a few milliamperes (mA) is adopted. This is for the following reasons.

(1) The LED (Fig. 1) is small and light like a pea, although the size of one element is 5 mm in diameter, 7 to 8 mm in length, and 0.3 g in weight even if it is a normal one. Ultra bright L which was developed and appeared on the market at a rapid tempo
In the case of the ED, at a DC rated current of 20 mA (required input voltage 1.8 to 3.6 V), luminous intensity candela (cd) and optical output several milliwatts (mW), which is about 1 as compared with the conventional LED.
It emits a light as bright as 00 times.

(2) The LED was originally developed as an optical display element (optical display element) and is now widely used for panel displays of various electric devices and electronic bulletin boards. If a plurality of elements are arranged two-dimensionally close to each other, they can be used as a light source for illumination. (3) The LED has a life of tens of thousands of hours, which is ten times longer than that of a fluorescent lamp, not to mention an electrothermal lamp (light bulb).

(4) Unlike ordinary light emitters such as electrothermal lamps and fluorescent lamps, LEDs emit a beautiful pure color light whose emission wavelength band in the spectrum is extremely narrow and which is close to monochromatic light. (5) The entire semiconductor light emitting chip (very small, about 0.3 mm square) and the two current terminals are covered with a very hard plastic lens such as hard epoxy resin (Fig. 1), so it breaks during normal use. It is extremely resistant to shock and vibration, and is also resistant to moisture.

(6) Since the light emission of the LED has an appropriate directivity (FIG. 1), the object can be efficiently irradiated. Further, since the action of the so-called inverse square law of light that the illuminance of light is inversely proportional to the square of the distance from the light source is small, the illuminance does not decrease so much even if the object is moved away from the light source. (7) The light emission of the LED is due to the electron emission inside the substance, and the generation of heat is extremely small. For this reason, the plant grows during cultivation and becomes taller, and the leaves and stems do not burn even if they come into direct contact with the LEDs.

(8) LED has a rated current (normally 20 mA)
In the following, since the input current and the emitted light intensity are almost proportional to each other, the irradiation light intensity can be freely and quantitatively controlled by the current. (9) LEDs are products that are mass-produced in units of one million pieces, and the price will be as low as tens to hundreds of yen per unit, not only immediately after development. In addition to the various features of the LEDs listed in (1) to (9) above, L of the plant incubator of the present invention is used for the following reasons.
The ED light source has an emission peak wavelength of 660 nanometers (n
m) near super bright red LED and emission peak wavelength is 4
Both ultra-bright blue LEDs around 50 nm were mixed and used.

(10) Chlorophyll (chlorophyll), which plays a central role in photosynthesis of plants, does not absorb light uniformly, but shows clear absorption peaks near red 660 nm and blue 450 nm (FIG. 2). ). In relation to this, the wavelength characteristic of photosynthesis shows a first peak near 660 nm,
It has a second peak near 450 nm. This 450n
Blue light around m also affects a photoreaction system called a high energy reaction system of plants, and is essential for healthy morphogenesis of plants.

(11) The red LED having a wavelength of 660 nm is
It is most produced among visible light LEDs, and has the highest brightness. Currently, a maximum brightness of 10 cd class is being developed. (12) It was difficult to manufacture a high-intensity blue LED until 1993, when it was said that the debut in the 21st century was in the optoelectronics industry and academia. However, in 1993, Nichia was the first in the world to have a luminous intensity of 1 cd (currently 2 cd), which is 100 times brighter than conventional blue LEDs at the product level, and has an emission wavelength of 450 nm, the shortest wavelength. Bright blue LED
Was developed and immediately commercialized.

(13) Kenmasa Okamoto, one of the present inventors, has found that the emission wavelength of an ultra-high brightness red LED of 660 nm and the emission wavelength of an ultra-high brightness blue LED of 450 nm most effectively contribute to photosynthesis and growth of plants. Focus on the coincidence that it is the same as that of red light and blue light. Immediately red LED (3
cd, diameter 5 mm, made by Sharp) 88 pieces and blue LED
Trial cultivation of plants (lettuce seedlings) by producing a planar light source in which 88 pieces (1 cd, diameter 5 mm, manufactured by Nichia Corporation) were evenly arranged and mounted on one printed circuit board, 1994 July
Moon succeeded in this. With only red and blue LEDs,
It was the first time in the world to announce that healthy plant seedlings would grow with only 7 watts of light source power consumption (published in October 1994, 1994 Shikoku Branch Union Conference on Electrical Association of Japan, p.
109, Kenzo Okamoto, Tomohiro Yanagi, "Development of a light source for growing plants using blue / red super bright LEDs"). Subsequent experiments also confirmed that vegetables such as spinach grow on red / blue LEDs.

From the above (10) to (13), it can be seen that the light source for plant cultivation comprising a mixture of ultra-bright red LED and blue LED has very high utilization efficiency of light spectrum and little waste of light. . FIG. 2 shows the red LE used in the present invention.
D (Toshiba TLRA120, wide-angle radiation type) and blue LE
The emission spectrum of D (Nichia NLPB520, wide-angle radiation type) is shown.

2. Installation of light source No matter what kind of light source is used, in culture using conventional glass or resin culture vessels, it is natural to place the culture vessel below the light source one-dimensionally or two-dimensionally. It was impossible to put them on top of each other. In addition, the distribution and uneven distribution of the light illuminance on the culture fence are remarkable, and the truly effective culture area is limited. Therefore, we focused on the feature of the LED light source that it is small, lightweight, robust, has a long life, and can be driven with low power with almost no heat generation (thus, it can be fed with a thin and light electric cord). We devised a container that is directly attached to the lid of the vessel, and a small, lightweight, and simple stand-alone culture container that is a type that mounts a mixed light source of red and blue LEDs on top of the lid of the culture container. Such an LED light source-installed culture container has a very practical feature, which is not available in the past, that it can be stacked.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. (1) The red LED 8 and the blue LED 9 are arranged on one printed circuit board (10 cm × 10 cm, thickness 1.6 mm), and this is placed on the lid 7 (11c) of the culture container as shown in FIG. 3 (a).
It was attached to m x 11 cm, height 17 mm, and the lid itself was used as the light source (hereinafter this is LED CAP <red.
Cap>). The entire container has a shape shown in FIG. 3 (b) and is composed of a plastic frame 13 and a breathable transparent resin film 14, and a rockwool medium 15 is contained inside.
Is accommodated, and the lid 7 can be attached by the fixed lever 16. The weight of the LED CAP itself is 100
g, the total weight (excluding water and culture solution) including rock wool when the LED CAP is attached is as light as 200 g.
Even with the LED CAP attached, the overall size is 1 vertical.
The original size is 1 cm × width 11 cm × height 14 cm.

(2) The LED CAP 17 can also be used by stacking it on the lid of another culture container 29 as shown in FIG. In this case, it is extremely easy to connect and disconnect the LED CAP light source and the container. (3) By integrating the container and the LED CAP in this way, an external light source such as a fluorescent lamp becomes unnecessary. Therefore, as shown in FIG. 5, the culture vessels can be stacked and the cultivation space can be fully utilized three-dimensionally. FIG.
Is a conventional cultivation method using a fluorescent lamp as a light source, and culture containers cannot be stacked.

(4) The circuit connection of the red LED and the blue LED is finalized in consideration of the favorable condition that the optimum operating voltage of the former is 1.8V and that of the latter is exactly doubled to 3.6V. In addition, an appropriate combination of series connection and parallel connection was performed so that the current input terminals to the LEDs would be the simplest two terminals and that a current within the rating would flow to each LED with respect to the input voltage (Fig. 7). ).

(5) In relation to (4) above, LED C
By connecting a bridge rectifying element for converting alternating current (AC) into direct current (DC) between the current input terminal and the LED circuit on the substrate of the AP, or by additionally providing an AC / DC rectifying circuit, the LEDCAP Can be used, for example, by directly connecting to a household AC power supply AC100V outlet (FIG. 8). Further, by incorporating a circuit that makes use of the rectifying function of the LED itself, it is also possible to eliminate the AC / DC rectifying circuit described above and connect the LED circuit directly to a household AC power source for use.

(6) Regarding the number of red LEDs and blue LEDs to be used, the component ratio of the photon flux density of the red light and the blue light in the combined irradiation light is the optimum value of red light 70- The respective numbers were selected so that 95% and 30 to 5% of blue light were obtained. Fig. 9 shows 36 red LEDs (Toshiba TLRA12) on a 10 cm square printed circuit board.
0) and 9 blue LEDs (Nichia NLPB52
0) DC LEDs LED CAP (circuit of FIG. 7) in which 45 LEDs in total are evenly arranged are mounted on the container of FIG. 3 to the cultivation floor located at about 10 cm below the LED (rock wool for hydroponics). , 9 cm × 9 cm × 3 cm thickness) The relationship between the photon flux density at the center of the plane and the DC input current, and both are in a proportional relationship. From this, it is understood that the irradiation light can be continuously controlled by the electric current. In FIG. 9, this L
Rated input current I = 60mA to ED CAP (L in Fig. 7
The average photon flux density is 66 μmolm ⁻² s ⁻¹ when an average of 20 mA is applied per ED), but this light intensity is
The value is sufficient for cultivating plant seedlings and performing micropropagation. In the case of FIG. 9, the photon flux density component ratio of red light and blue light is 86:14.

Using the culture vessel equipped with this LED CAP, low-profile vegetables such as saladana, lettuce, radish sprouts, and komatsuna were cultivated, and micropropagation of orchid (cymbidium) and eucalyptus clone seedlings was carried out with good results. Got Test Example A DC type LED CAP whose wiring diagram is shown in FIG. 7 was placed on a culture vessel (10 cm in length × 10 cm in width × 14 cm in height) in which a fluororesin film as shown in FIG. 4 was supported by a frame made of polycarbonate resin. Put them on top of each other and put on Cymbidium Me
lody Fair 'Marilyn Monro
Aseptic culture of the clone shoots of e ′ ) (three developed leaves, root excision) was performed. Medium and medium support were modified Vacin & Went liquid medium (sugar-free) and rockwool multiblock (Grodani, Netherlands), respectively.
a) was used. 17 forward current per LED
When fixed at mA, the photon flux density at the center of the surface of rockwool, which is the medium support, was 45 μmol / m ² / s.
The composition ratio as the photon flux density of red light and blue light was 86% for red light and 14% for blue light. The culture was carried out at 25 ° C. for 96 days in an incubator to which 3000 ppm of carbon dioxide was applied. As a control, the same fluororesin film culture container was used to grow a fluorescent lamp for plant growth (Plant Torx manufactured by Toshiba Lightec, 45 μmol /
m ² / s) and the conventional method of using a flask agar medium for illuminating with a plant growing fluorescent lamp (same as above). The results are shown in Table 1
The test plot using CAP showed good growth.

[0026]

[Table 1]

[0027]

The culture container with an LED light source and the LED light source for a culture container according to the present invention are compact and lightweight, have a very simple structure and structure, and can be mass-produced at a low price. Therefore, they can be used for seedling production by micropropagation and adventitious embryos. It can be used for proliferation. Of course, it is also useful as a simple incubator in cultivation experiments and bio experiments. Furthermore, not only for agricultural experiments and plant factories, but also for the general public, a home garden that uses an AC power source in the home (home garden) and hobbies and interiors (use the beauty of LED light).
The new use as a combined table garden is also promising, and it has the potential to create a new market. Further, if a culture container material having low moisture permeability and high carbon dioxide gas permeability is used in the present invention, it is considered possible to grow vegetables in a space station that requires high efficiency.

[0028]

[Brief description of drawings]

FIG. 1 shows the shape and structure of an LED.

FIG. 2 is an optical absorption spectral characteristic of chlorophyll (chlorophyll),
It is an emission spectrum figure of the red LED and blue LED used by this invention.

FIG. 3 is a light source (LED CAP) used in the examples of the present invention.
FIG. 3 is a bird's-eye view showing a culture container equipped with a light source.

FIG. 4 is a diagram showing a method of mounting LED CAPs on a lid of a culture container in an overlapping manner.

FIG. 5 is a diagram showing an example of stacking and using the incubator of the present invention.

FIG. 6 is a diagram showing an example of cultivation using a conventional plant growing fluorescent lamp.

FIG. 7: Red LED and blue LE in LED CAP
It is an example of circuit connection of D (when using a DC power supply).

FIG. 8 is a circuit example of an LED CAP for an AC power supply (AC100V).

FIG. 9 is a diagram showing the relationship between the light intensity (photon flux density) and the input current (DC) in the central portion of the rockwool surface of the culture container of the present invention.

[Explanation of symbols]

 1 Anode Terminal 2 Cathode Terminal 3 Light Emitting Chip 4 Epoxy Resin Lens 5 Radiant Light 6 Input Current 7 Lid 8 Red LED 9 Blue LED 10 Rubber Packing 11 Plastic Spacer 12 Culture Vessel Body 13 Plastic Frame 14 Ventilation / Water Shielding Film 15 Rockwool 16 Fixed Lever 17 Red Cap 18 Power Cord 19 Stopper 20 Culture Container 21 Fence 22 Fluorescent Lamp for Plant Growth 23 DC Red Cap 24 Red LED 25 Blue LED 26 Red LED 27 DC Current Source 28 AC Red Cap 29 Bridge Rectifier 30 Red LED 31 Blue LED 32 Red LED 33 Resistor 34 AC outlet plug

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 000005968 Mitsubishi Kagaku Co., Ltd. Marunouchi 2-5-2, Chiyoda-ku, Tokyo (72) Inventor Kenzo Okamoto 1-13-13, Showacho, Takamatsu City, Kagawa Prefecture No. 406 (72) Inventor Michio Tanaka 644-2 Hiraki, Miki-cho, Kida-gun, Kagawa Prefecture (72) Inventor Yoshimi Makino 6-34-22 Hinominami, Konan-ku, Yokohama

Claims (9)

[Claims] 1. An LED for plant cultivation, which has a light emitting diode element and is configured to be mounted on an upper portion of a plant culture container.
light source. 2. A wavelength region of 630 nm arranged on a substrate.
2. The light source according to claim 1, comprising a red LED having a wavelength of 380 nm to 680 nm, or an element of the red LED and a blue LED having a wavelength range of 380 nm to 480 nm. 3. The plant cultivation L according to claim 1 or 2, further comprising a rectifying element or a rectifying circuit.
ED light source. 4. The LED according to claim 1, which can be directly used as a household or commercial AC power supply without a transformer, a rectifying element or a rectifying circuit by adjusting the LED connecting circuit by utilizing the rectifying function of the LED. LED light source for plant cultivation. 5. A culture container comprising a container body and a lid, wherein a light emitting diode (LED) element is directly mounted on the lid portion, and an individual LED light source mounting type plant culture container is provided. 6. An individual LED light source mounting type plant culture container, characterized in that a light source device using LEDs as light emitting elements is mounted on the culture container in an overlapping manner. 7. The plant culture container according to claim 5, which is equipped with the light source according to any one of claims 2 to 4. 8. The plant culture container according to claim 5, wherein at least a part of the container body is made of a breathable material. 9. A container body comprising a frame and a breathable transparent resin film and containing a culture medium therein, and a red LE.
The plant culture container according to any one of claims 5 to 8, which is equipped with a light source composed of D or red LED and blue LED, and which comprises a lid having a means for fixing the rubber packing and the container body.