KR20130109996A - Led lamp for plant cultivation - Google Patents

Abstract

PURPOSE: An LED lamp for plant cultivation is provided to switch a drive circuit of a red LED element and a blue LED element by using a switching circuit and a timer circuit, thereby alternately emitting red light and blue light. CONSTITUTION: A main body (1) has a straight tube fluorescent lamp shape. A red LED element (3), a blue LED element (4), and a circuit board (5) are arranged inside the main body. A power supply terminal (2) is equipped on the end of the main body. A timer circuit which controls the switching operation of a switching circuit is provided on a drive circuit on the circuit board. An input unit (6) sets the current supply time for the red LED element and for the blue LED element on the timer circuit.

Description

LED lamp for plant cultivation {LED LAMP FOR PLANT CULTIVATION}

The present invention relates to an LED lamp for plant cultivation. More specifically, the present invention relates to a straight fluorescent lamp type LED lamp for illuminating red and blue illumination light alternately to cultivated plants.

Background Art Conventionally, in plant cultivation, a technique of illuminating plant seedlings with artificial light and urging seedlings has been introduced. By accelerating the growth of plants, the growing period can be shortened to increase the number of harvests in the same place. In addition, the yield can be increased if plants can be grown larger during the same growing period.

As a plant cultivation method using illumination of artificial light, for example, Patent Document 1 discloses a lighting device for a plant configured to alternately illuminate a plant with green light and white light. The lighting device alternately illuminates the green light having a wavelength of 500 to 570 nm and the white light having a wavelength of 300 to 800 nm to form a change in day and night, and facilitates the current action of the plant to promote the growth of the plant.

For example, Patent Literature 2 discloses cultivation, growth, cultivation and organization of plants by simultaneously or alternately lighting a light emitting diode emitting blue light (400-480 nm) and a light emitting diode emitting red light (620-700 nm). Disclosed is a light source for plant cultivation that irradiates light energy for cultivation. This plant cultivation light source intends to cultivate a plant efficiently by irradiating only the light of the wavelength corresponding to the chlorophyll light absorption peak (near 450 nm and around 660 nm).

Patent Literature 2 discloses a light source capable of mixing and arranging a light emitting diode emitting blue light and a light emitting diode emitting red light on one or a plurality of substrates (boards), and lighting these light emitting diodes simultaneously or alternately. (See Document 1 above). However, Patent Literature 2 compares the unhealthy growth, such as cultivation under daylight, in comparison with unhealthy growth such as cultivation under sunlight, in the comparison of blue light alone irradiation, red light alone irradiation, blue light and red light simultaneous irradiation. ] Is confirmed (refer the said document paragraph "0011"), and the growth promoting effect at the time of irradiating blue light and red light alternately is not confirmed. Therefore, the light source described in patent document 2 is not substantially comprised by the structure which irradiates blue light and red light alternately.

On the other hand, LED lamps are rapidly spreading in recent years instead of fluorescent lamps. LED lamps have the advantage of low power consumption and long life compared to fluorescent lamps. Moreover, when attaching this LED lamp, it is also possible to use the existing fluorescent lamp mechanism as it is and to install as an LED lighting apparatus only by replacing only a lamp from fluorescent lamp to LED lamp. For example, Patent Document 3 discloses a straight tube fluorescent lamp type LED lamp that is set to a prescribed length according to the wattage of the fluorescent tube and that the fluorescent tube can be separated and simply attached to an existing fluorescent lamp fixture.

Japanese Patent Laid-Open No. 6-276858 Japanese Patent Laid-Open No. 8-103167 Japanese Patent Laid-Open No. 2001-351402

In order to improve productivity, a light source for plant cultivation that is excellent in growth promoting effect, has good energy efficiency and can be easily installed is expected. The present invention aims to provide a light source for plant cultivation that satisfies these demands.

As a result of earnestly examining the effect of promoting the growth of plants by illumination in artificial light, the inventors have surprisingly found that a very remarkable effect is obtained by a simple method of alternately illuminating red and blue light (see Test Example). . This plant cultivation method which promotes plant growth by independently independently performing the sequence of illuminating the plant only with red light and the sequence of illuminating the plant only with blue light within a certain period of time is referred to as a "Shigyo Method".

Based on the above knowledge, the present invention has a straight fluorescent lamp shape, a main body portion in which a red LED element and a blue LED element are disposed, a feed terminal provided at an end of the main body portion, and a current supplied from the feed terminal. Provided is a plant cultivation LED lamp having a switching circuit flowing by switching to a driving circuit of an LED element or a driving circuit of the blue LED element.

According to this plant cultivation LED lamp, an execution method can be performed by comparatively simple construction, using the existing fluorescent lamp fixture etc. as it is.

It is preferable that this plant cultivation LED lamp has a timer circuit which controls the switching operation of the drive circuit by the said switching circuit. In this case, it is preferable to have an input section for setting the current supply time to the red LED element and the current supply time to the blue LED element in the timer circuit.

This plant cultivation LED lamp can be equipped with an alternating current / direct current converter inside or outside.

This plant cultivation LED lamp may be such that the red LED element having a center wavelength of 570 to 730 nm and the blue LED element having a center wavelength of 400 to 515 nm are disposed.

In the present invention, red light means light having a wavelength of 570 to 730 nm, and blue light means light having a wavelength of 400 to 515 nm.

In the present invention, the "direct fluorescent lamp" refers to a conventional straight fluorescent lamp, and more specifically, it is prescribed in 2.3.1 "List of data sheets" of JISC7617-2 "Intuitive fluorescent lamp-Part 2: Performance regulation". Let's say a straight fluorescent lamp which became. In addition, "a straight fluorescent lamp mechanism" shall mean the fluorescent lamp mechanism which has the shape, the dimension, and the function which can attach and use the conventional straight fluorescent lamp as mentioned above.

In the present invention, "plants" include at least leafy vegetables, fruit trees, and cereals, and algae, lichens, and the like are also broadly included.

(Effects of the Invention)

According to the present invention, there is provided a light source for plant cultivation that is excellent in growth promoting effect, has good energy efficiency, and which can be easily installed.

1: is a schematic diagram explaining the structure of the LED lamp for plant cultivation which concerns on 1st Embodiment of this invention.
2 is a circuit diagram of an LED lamp A for plant cultivation.
It is a figure explaining an example of the control pattern of the LED lamp for plant cultivation by this invention.
It is a schematic diagram explaining the structure of the LED lamp for plant cultivation which concerns on 2nd Embodiment of this invention.
5 is a circuit diagram of an LED lamp B for plant cultivation.
FIG. 6 is a drawing substitute photograph showing the growth result after 7 days of germination in Test Example 1. FIG.
FIG. 7 is a drawing substitute photograph showing growth results after 14 days of germination in Test Example 1. FIG.
FIG. 8 is a drawing substitute photograph showing growth results after 21 days of germination in Test Example 1. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, the preferable form for implementing this invention is demonstrated, referring drawings. In addition, embodiment described below shows an example of typical embodiment of this invention, and the scope of this invention is not interpreted narrowly by this. The description is made in the following order.

1. LED lamp for plant cultivation according to the first embodiment

(1) main body

(2) drive circuit

(3) control pattern

(4) Input part and display part

2. LED lamp for plant cultivation by 2nd Embodiment

3. Cultivated Plant

(1) leafy vegetables

(2) fruit trees

(3) cereals

(4) algae

(5) lichens

1. LED lamp for plant cultivation according to the first embodiment

(1) main body

1: is a schematic diagram explaining the structure of the LED lamp for plant cultivation which concerns on 1st Embodiment of this invention. 2 is a circuit diagram of the LED lamp A for plant cultivation.

The LED lamp A for plant cultivation is comprised including the main-body part 1 and the terminal 2 provided in the edge part of the main-body part 1, and is comprised. In general, one or two terminals 2 are provided at the ends of the main body 1. Although the shape of the terminal 2 should just be a various clasp shape, it does not specifically limit, For example, the L-shaped pin base (GX16t-5) etc. which are internal standards of the Japan Bulb Industry Association can be used.

The main body 1 has a straight fluorescent lamp shape. By making the shape of the main-body part 1 into the shape of a conventional straight fluorescent lamp, it becomes possible to attach the plant cultivation LED lamp A to the straight fluorescent lamp mechanism D for attaching a conventional straight fluorescent lamp. The terminal 2 also functions as a support pin at the time of attachment of the straight fluorescent lamp mechanism D to the socket 10.

The main body 1 is a cylindrical tube made of transparent or translucent plastic or glass, similar to a known straight fluorescent lamp. The tubular body may be of a single material, but for example, the half body on the radial side (lower side) of light from the LED element is made of plastic such as polycarbonate, and the top half body is made of metal such as aluminum. It may be.

The red LED element 3, the blue LED element 4, and the circuit board 5 for driving these are arrange | positioned inside the main body part 1. The red LED element 3 and the blue LED element 4 are each arranged in array form on a circuit board.

In the attachment state to the linear fluorescent lamp mechanism D, the circuit board 5 is connected to an AC / DC converter (AC / DC converter) 11 included in the linear fluorescent lamp mechanism D. As shown in FIG. An AC power supply 12 is connected to the AC / DC converter 11. In FIG. 2, the terminal 2 arrange | positioned at the one side of the main-body part 1 was made into a feed terminal, and the case where one of the 2-pin arranged terminals 2 arrange | positioned at the other end was used as an earth terminal was shown. Earth is connected to the metal of the tube.

In addition, in the LED lamp for plant cultivation according to the present invention, the wiring system is not particularly limited, and in addition to the method of applying between two pins on one side, the method of applying between one pin at each end may be used.

As the red LED element 3, an element emitting light having a wavelength of 570 to 730 nm, preferably a light having a wavelength of 635 to 660 nm as a center wavelength is used. In the blue LED element 4, light having a wavelength of 400 to 515 nm, preferably light having a center wavelength of 450 nm is preferably used. The red LED element 3 and the blue LED element 4 may have a predetermined wavelength range using the wavelength as the center wavelength. As a wavelength region, if it is blue light, it can be 450 +/- 30 nm, Preferably it is 450 +/- 20 nm, More preferably, it can be 450 +/- 10 nm.

The red LED element 3 and the blue LED element 4 have a monochromatic line light source or a monochromatic panel light source in which only one of the red LED element 3 and the blue LED element is arranged in a line or plane shape, or one red LED element. And a SMD line light source in which linear arrangement of two chips surface mount devices (SMDs) mounted by combining a single blue LED element can be used.

Examples of LEDs emitting light in the wavelength range include aluminum gallium indium phosphorus-based light-emitting diodes (gallium phosphorus-based substrates, red wavelengths) sold by Showa Denko Co., Ltd. as model number HRP-350F in red LEDs. 660 nm), and the blue LED includes a light emitting diode of the company product number GM2LR450G.

The LED element is small in size and long in life, and emits light at a specific wavelength depending on the material, so that there is no unnecessary heat radiation. Thus, even when the LED element is irradiated close to the plant, no obstacle such as chlorophyll occurs. For this reason, by using an LED element for a light source, it becomes low power cost compared with other light sources, and it becomes possible to cultivate with space saving.

In principle, LED devices are capable of blinking at very high frequencies of several megahertz (MHz). For this reason, by using an LED element for a light source, it becomes possible to perform the switching of the step which illuminates a plant only by red light only, and the step which illuminates a plant only by blue light very fast.

(2) drive circuit

The driving circuits of the red LED element 3 and the blue LED element 4 on the circuit board 5 are supplied with the direct current supplied from the AC / DC converter 11 via the power supply terminal to the red LED element 3 or the blue LED element. The switching circuit 51 which switches and flows to the drive circuit of (4) is arrange | positioned. The switching circuit 51 can be comprised by the general-purpose LED driver.

Moreover, the timer circuit 52 which controls the switching operation of the drive circuit of the switching circuit 51 is arrange | positioned in the drive circuit on the circuit board 5. The timer circuit 52 can be configured by a one-chip microcomputer that is commonly used.

The LED lamp for plant cultivation A is to irradiate red light and blue light alternately by switching the drive circuits of the red LED element 3 and the blue LED element 4 by the switching circuit 51 and the timer circuit 52, The execute method is executable. That is, in the plant cultivation LED lamp A, the switching circuit 51 and the timer circuit 52 independently perform the step of illuminating the plant only with red light and the step of illuminating the plant with only blue light separately within a predetermined period. Next, the control pattern by the switching circuit 51 and the timer circuit 52 is demonstrated in detail.

(3) control pattern

The switching circuit 51 is a red LED element 3 and a blue LED element based on the current supply time to the red LED element 3 and the current supply time to the blue LED element 4 set and maintained in the timer circuit 52. The current is switched and flowed through the respective driving circuits (4) to control the light emission time of the red LED element 3 or the blue LED element 4. Hereinafter, the step in which only the red LED element 3 emits light by the switching circuit 51 is called "red light illumination step", and the step in which only the blue LED element 4 emits light is called "blue light illumination step".

The one-chip microcomputer constituting the timer circuit 52 includes a drive current of the red LED element 3 or the blue LED element 4 in addition to the current supply time to the red LED element 3 or the blue LED element 4. The size may be set and maintained. In this case, the switching circuit 51 changes the current value of each of the red LED element 3 and the blue LED element 4 to the driving circuit based on the set current value, thereby changing the red LED element 3 or the blue LED element ( The emission intensity of 4) is also controlled.

3 is a diagram illustrating a control pattern. This embodiment performs a red light illumination step and a blue light illumination step alternately and continuously.

In the figure, reference numerals S ₁ denotes a red light one trillion people step, the sign S ₂ is one trillion people step blue light. In this embodiment, the red light illumination step S ₁ and the blue light illumination step S ₂ are successively performed alternately, and the irradiation cycle consisting of the red light illumination step S ₁ and the blue light illumination step S ₂ is repeatedly performed. .

Thus, growth can be remarkably promoted by alternately irradiating plants with red light and blue light (see Test Example). It is also possible to improve the yield by suppressing overgrowth.

Although the case where the procedure is started from the red light illumination step S ₁ in the first irradiation cycle C ₁ has been described as an example, the red light illumination step S ₁ and the blue light illumination step S in each irradiation cycle are described. Which one of ₂ ) is performed first is arbitrary.

In the above-described control pattern, the time of one irradiation cycle is the longest growing period. In addition, the shortest time can be arbitrarily set as long as the effect of this invention is shown. One irradiation cycle may be, for example, a time (hr) as a unit of time length, and a longer time length unit (for example, day) or a shorter time length unit (for example, minute ( minutes)] may be used.

For example, when one irradiation cycle is made per day, the red light illumination step S ₁ may be 12 hours, and the blue light illumination step S ₂ may be 12 hours. For example, if the irradiation cycle is repeated four times a day, one irradiation cycle may be 6 hours, and the red light illumination step S ₁ may be 3 hours and the blue light illumination step S ₂ may be 3 hours. .

The time of one irradiation cycle may be changed to the irradiation cycle CM of the Nth time and the irradiation cycle CM of the Mth time (M is one or more integers different from N). For example, the irradiation cycle CN may be 12 hours, and the subsequent irradiation cycle CN + 1 may be 6 hours.

The time ratio between the red light illuminating step S ₁ and the blue light illuminating step S _{2 in} one irradiation cycle may be arbitrary. For example, the above-mentioned first control case to a single irradiation cycle, the pattern in the day, "red light one trillion people step (S _1), the blue light one trillion people step (S _2)" to "12 hours, 12 hours (1: 1 ) "," 16 hours, 8 hours (2: 1) "," 21 hours, 3 hours (7: 1) "and the like can be arbitrarily set.

The amount of light (intensity) of the red light and the blue light in the red light illuminating step S ₁ and the blue light illuminating step S ₂ is not particularly limited, but is, for example, each of photosynthetic photon flux flux density (PPFD). It is 1-1000 micromol / m <2> s, Preferably it is 10-500 micromol / m <2> s, Especially preferably, it becomes about 50-250 micromol / m <2> s.

In addition, the light quantity (intensity) ratio of the red light and blue light in each said step is 1: 1, 2: 1, 4: 1, 10: 1, 20 by "red: blue" or "blue: red", for example. It can be set arbitrarily, such as: 1.

In addition, the light quantity of red light and blue light may be changed in the said range, for example, the light quantity may change in the irradiation cycle CN of the Nth time (N is an integer of 1 or more). In addition, you may change light quantity within the said range in the irradiation cycle CM of the Nth time and the irradiation cycle CM of the Mth time (M is 1 or more integer different from N).

(4) Input part and display part

The plant cultivation LED lamp (A) is an input unit (6) for setting and storing the current supply time and the current value to the red LED element (3) or the blue LED element (4) in the one-chip microcomputer constituting the timer circuit (52). ).

When the input unit 6 is an analog signal conversion switch using a variable resistor, the input unit 6 can be provided as a slide switch on the upper half of the main body unit 1. In addition, when performing digital input, the input part 6 may be comprised by a push button etc. Alternatively, the input unit 6 may be configured to input a current supply time and a current value using an infrared remote control as an infrared light receiving unit.

In the plant cultivation LED lamp A, the input circuit 6 executes the above-described control pattern on the switching circuit 51 by setting a desired current supply time and current value in the one-chip microcomputer constituting the timer circuit 52. It is possible to carry out plant cultivation by the execution method.

Moreover, it is preferable to provide the display part 7 for checking the set value of a current supply time and a current value in the plant cultivation LED lamp A as needed. The display unit 7 may be an analog or digital clock, an LED indicator, or the like. Further, in the LED lamp for plant cultivation according to the present invention, the setting of the current supply time and the current value of the red LED element 3 or the blue LED element 4 may be performed by wires or wirelessly by connecting a control line to each lamp. It is also possible to collectively control the switching circuit 51 of the lamp.

2. LED lamp for plant cultivation by 2nd Embodiment

It is a schematic diagram explaining the structure of the LED lamp for plant cultivation which concerns on 2nd Embodiment of this invention. 5 is a circuit diagram of the LED lamp B for plant cultivation.

The plant cultivation LED lamp B differs from the above-described DC cultivation plant cultivation LED lamp A in that it has a built-in AC / DC converter 11 and is a commercial power supply direct connection or an existing ballast connection type. In addition, the plant cultivation LED lamp (B) is different from the plant cultivation LED lamp (A) of the method of applying between the terminals of one-side 2-pin in that the wiring method is a method of applying between the terminals of each pin 1 terminal. Hereinafter, the point different from the plant cultivation LED lamp A with respect to the plant cultivation LED lamp B is demonstrated.

In the plant cultivation LED lamp B, an AC / DC converter (AC / DC converter) 11 is mounted on the circuit board 5. For this reason, the plant cultivation LED lamp B can be attached to the existing ballast (E). In the state of attachment to the ballast E, the circuit board 5 is connected to an AC power supply 12 connected to the ballast. In FIG. 5, the case where the power supply terminal was made into one pin of each side of the terminal 2 arrange | positioned at the both ends of the main-body part 1 by 2 pins was shown. The remaining 1 pin on one side of the main body 1 becomes an earth terminal, and the earth is connected to the metal of the tubular body.

The ballast connected in the LED lamp for plant cultivation according to the present invention may be an existing one, and the type of the ballast is not particularly limited, and is a magnetic starter type, a magnetic rapid start type, an electronic type, or the like. You can do

In addition, since the LED lamp B for plant cultivation incorporates an AC / DC converter in the circuit board 5, it can be directly connected to a general commercial AC power supply as well as a ballast. The wiring method to a commercial power supply is not specifically limited, either the method of applying between two pins of one side, and the method of applying between terminals of 1 pin of both ends may be sufficient.

The shape of the main body 1 of the LED lamp B for plant cultivation or the shape of the terminal 2, the red LED element 3, the blue LED element 4, the switching circuit 51 and the timer circuit 52 are included. The structure of the drive circuit of these elements, and the control pattern of the switching circuit 51 are the same as the LED lamp A for plant cultivation. In addition, the structure of the input part 6 and the display part 7 is the same as that of the LED lamp A for plant cultivation.

3. Cultivated Plant

The cultivated plant to which the present invention is intended is not particularly limited and may be vegetables, potatoes, mushrooms, fruits, legumes, grains, seeds, algae, moss, ornamental plants and the like. Moreover, the cultivation form of these plants is not specifically limited, either hydroponic cultivation, earth cultivation, etc. may be sufficient. For algae, a culture medium such as a liquid medium or agar medium may be arbitrary.

(1) leafy vegetables

As leafy vegetables, lettuce, green onions, crisp greens, Boston lettuce, garland chrysanthemum, parsley, green onions, rapeseed greens, karashimizuna, mustard greens, wasabi, watercress, cabbage, pickled vegetables, bok choy, cabbage, cauliflower, broccoli, drops Cabbage, onion, garlic, salt bridge, leek, asparagus, celery, spinach, buttercups, dumplings, mutton, coltsfoot, perilla, various herbs and the like. In addition, the so-called "Baby Leaf" and leafy vegetables such as Detroit, lettuce, Rucola, pinogreen, red romaine and chicory, which are mainly eaten as young leaves, are also mentioned.

Lettuce includes cotyled lettuce, non-clus lettuce and semi-clus lettuce, for example, leaf lettuce, ruffle lettuce, romaine, green wave, green leaf, red leaf, ruffle ice (registered trademark), river green (registered trademark) , Frill reef, fringe green, no-tip, moco lettuce, lettuce, and skirt lettuce.

Various herbs include, for example, basil, Italian parsley, and the like.

In addition, tomatoes, cantaloupe, cucumbers, strawberries, pumpkin, watermelon, eggplant, bell pepper, okra, kidney beans, green beans, peas, green beans, corn and vegetables, radish, turnips, burdock, carrots, sweet potatoes, taro, sweet potatoes, yams, Root vegetables such as ginger, wasabi and lotus root can also be cultivated.

(2) fruit trees

Examples of fruit trees include mangoes, pineapples, figs, blueberries, raspberries, blackberries, vozenberries, grapes, cherry, cranberries, honeyberries, gooseberries, currants, papayas, passion fruit, and dragon fruit.

(3) cereals

Examples of the cereals include amaranth, crude, oats, barley, sorghum, wheat, rice, glutinous rice, buckwheat, corn, barley, blood, and rye.

(4) algae

Algae include a wide range of protozoa such as green algae, brown algae, cyanobacteria and red photosynthetic bacteria, and aquatic photosynthetic organisms such as aquatic plants. As algae, specifically, blue algae, prokaryotic algae, red algae, gray algae, crypto algae, coarse algae, golden algae, diatoms, brown algae, yellow algae, flax algae, rapid algae (green algae), , Euglena algae, pracino algae, green algae, axle algae and the like.

(5) lichens

Lichens include lichens belonging to the stream. For example, the moss of Grimmiales moss rock and frost moss, such as a so-called sand moss, such as Racomitrium japonicum, are mentioned.

As ornamental plants, various houseplants can be cultivated in addition to roses, mini roses and gentians.

[Example]

&Lt; Test Example 1 >

According to the present invention, test groups 1 to 8 having different light environments at the time of growth were prepared, and the comparison was made to verify the correlation between the irradiation pattern of artificial light and the growth promoting effect on plants.

A. Materials and Methods

(material)

In this test example, leaf lettuce (variety: summer surge) was used as a growth target. First, the seeds of the leaf lettuce were sown at equal intervals in 6 grains and the growing pit plate, and germinated under fluorescent lamps [12 hours long]. Three days from sowing to germination were placed under the same light environment in any of the test groups.

After germination, lettuce was grown for 21 days in each artificial meteorology with different light conditions. The environment of the artificial vapor phase machine was the same except for the light irradiation conditions, and the temperature was 25 to 27 ° C and the humidity was 50%.

(Light source)

The light source for the light environment of this test example includes a red LED (center wavelength: 660 nm, manufactured by Showa Denko HRP-350F), a red LED (center wavelength: 635 nm, manufactured by Showa Denko HOD-350F), and a blue LED (center wavelength). : 3 types of LED and fluorescent lamp of 450 nm, GM2LR450G by Showa Denko) and a white LED (near-ultraviolet 405 nm excitation, Kyocera TOP-V5000K) were used. One set of each LED has 240 red LEDs, 240 blue LEDs, and 128 white LEDs for both 660 nm and 635 nm.

Using each light source, the optical environment of the test groups 1-10 shown in Table 1 was created. Intensity of the light source is a light amount photosynthetic flux density (PPFD, μ㏖m ^-2 s ^-1) of about 140μ㏖m ^-2 at the center of the foot plate to the development s ^-1 (test group of about 80,000 80μ㏖m ^-2 s ^{- 1} ). When irradiating light of multiple wavelengths simultaneously or irradiating alternately, it adjusted so that the sum total of PPFD of each irradiation light might be about 140 micromol -2s ^{- 1} . The photosynthetic light quantity magnetic flux density (PPFD, μmol ⁻² s ⁻¹ ) in the test environment of the test groups 1 to 10 was represented by an average value of five points in the height near the soil surface that entered the growing feet. In addition, the detail of the light environment, irradiation light, and irradiation pattern of each test group is demonstrated below.

(Test group 1)

In this test group, lettuce was irradiated with red light (660 nm) and blue light (450 nm) alternately for 12 hours. In this test group, the time which does not irradiate any light is not set.

As for the light environment in this test group, PPFD averaged 80.7 micrometers ^-2 s ^-1 with respect to red light (660 nm). For blue light (450㎚) was PPFD average 56.4μ㏖m ^-2 s ^-1.

(Test group 2)

In this test group, lettuce was irradiated with red light (660 nm) and blue light (450 nm) simultaneously for 12 hours, and after that, it set the time which no light is irradiated for 12 hours, and repeated this.

(Test group 3)

In this test group, lettuce was irradiated with red light (660 nm) and blue light (450 nm) simultaneously for 24 hours. In this test group, the time which does not irradiate any light is not set.

Light environment in the test groups is the sum of the red light (660㎚) and blue light (450㎚) was PPFD average 145.3μ㏖m ^-2 s ^-1. The same applies to the test group 2.

(Test group 4)

In this test group, lettuce was irradiated with red light (635 nm) and blue light (450 nm) alternately for 12 hours. In this test group, the time which does not irradiate any light is not set.

(Test group 5)

In this test group, lettuce was irradiated with red light (635 nm) and blue light (450 nm) simultaneously for 12 hours, and after that, the time was repeated for 12 hours without setting any light.

(Test group 6)

In this test group, the lettuce was irradiated with only red light (660 nm) for 12 hours, and after that, the time was repeated without setting any light for 12 hours.

The optical environment in this test group had an average PPFD of 139.3 μmol ⁻² s ⁻¹ .

(Test group 7)

In this test group, the lettuce was irradiated with only red light (635 nm) for 12 hours, and after that, the time was repeated for 12 hours without setting any light.

PPFD of red light (635 nm) in this test group was about the same as that of test group 6.

(Test group 8)

In this test group, lettuce was irradiated with only blue light (450 nm) for 12 hours, and after that, the time was repeated for 12 hours without setting any light.

The optical environment in this test group had an average of 84.1 μmol ⁻² s ⁻¹ of PPFD.

(Test group 9)

In this test group, the lettuce was irradiated with only white light (405 nm excitation) for 12 hours, and then, this was repeated for 12 hours by setting a time for which no light was irradiated.

The optical environment in this test group had an average PPFD of 142.0 μmol ⁻² s ⁻¹ .

(Test group 10)

In this test group, the lettuce was irradiated with only a fluorescent lamp for 12 hours, and then, this was repeated for 12 hours by setting a time for which no light was irradiated.

The optical environment in this test group had an average PPFD of 139.8 μmol ⁻² s ⁻¹ .

B. Results

The above test groups 1 to 10 start to grow under different light conditions after germination, and after 7 days (after 10 days of sowing of seeds), 14 days (after 17 days of sowing) and 21 days (after 24 days of sowing). The growth state was observed and measured at each time point, and the comparison between the test groups was performed.

(7 days after growth)

Figure 6 shows the growth state of each test group 7 days after the start of growth in different light environment. In addition, Table 2 shows the stem length (mm), the first leaf length (cm), the number of leaves (sheets), and the leaf width (cm) in each test group at the same time point. The measurement result is shown. The measured value of each item describes the "average value" or the "minimum value-the maximum value" of 6 samples which were planted in the same growth pit plate.

As shown in Fig. 6 and Table 2, after 7 days of growth, the lettuce under the alternating irradiation of the red light (660 nm) and the blue light (450 nm) of the test group 1 had the first leaf length and the leaf width length compared to the other test groups. The long one was shown.

(14 days after growth)

Figure 7 shows the growth state of each test group 14 days after the start of growth in different light environment. In addition, in each photograph, the magnitude | size of a growth feet is the same. In addition, Table 3 shows the measurement results of the stem length (mm), the first leaf length (cm), the number of real leaves (sheets), and the leaf width (cm) in each test group at the same time. As for the measured value of each item, the "average value" or "minimum value-the maximum value" of 6 samples are described.

From Fig. 7 and Table 3, after 14 days of growth, the lettuce under the alternating irradiation of the red light (660 nm) and the blue light (450 nm) of the test group 1 was characterized in that the length of the first lobe was longer than that of the other test groups. In addition, the number of real leaves of test group 1 was about 1 or 2 sheets compared with other test groups.

(21 days after growth)

FIG. 8 is a photograph showing the growth state of each test group 21 days after initiation of growth under different light conditions. In addition, in each photograph, the magnitude | size of a growth feet is the same. Table 4 shows ground fresh weight (g), ground dry weight (g), main leaf trees (sheets), stem length (cm), leaf length (cm) in each test group at the same time point. The comparison result which made the growth result of the test group 10 (under fluorescent lamp) 100% about the leaf width length (cm) and the leaf length (cm) is shown. As for the measured value of each item, the "average value" of 6 samples is described like Table 2.

In Table 4, the lettuce fresh weight under the alternating irradiation of the red light (660 nm) and the blue light (450 nm) of the test group 1 was more than twice as heavy as the test group 10 (under the fluorescent lamp). Moreover, the lettuce fresh weight of the lettuce under alternating irradiation of the red light (635 nm) and blue light (450 nm) of the test group 4 was about 2 times compared with the test group 10. On the other hand, the lettuce of the irradiation of the red light and the blue light of the test group 2 and the test group 5 was heavier than the test group 10, although the ground fresh weight was less than the test group 1 or the test group 4 which performed the alternating irradiation. In addition, the ground fresh weight of the lettuce which was irradiated with red light (660 nm) and blue light (450 nm) at the same time for 24 hours was about the same as the weight of test group 2 having half the irradiation time. From these results, it was shown that alternating irradiation of red light and blue light promotes plant growth.

The main leaves of Test Group 1 were about the same as Test Group 2 or Test Group 10 at 21 days after growth, unlike 14 days after growth. This is considered to be because the growth that increases the number of leaves in Test Group 1 has reached a plateau state between 14 days and 21 days after growth.

In Test Group 1 and Test Group 4, the leaf length and the leaf width were longer than those in Test Group 10. This tendency was not observed in lettuce under the conditions of simultaneous irradiation of red and blue light in Test Group 2, Test Group 3, and Test Group 5. On the other hand, in the test group 2 and the test group 5, the stem length was longer than the test group 10. From these results, it was shown that alternating irradiation of red light and blue light can promote only leaf growth while suppressing overgrowth of stems compared to simultaneous irradiation.

Table 5 shows each of the assimilation engines (g) and non-assimilation engines (g) at the ground fresh weight (g) and ground dry weight (g) of each test group 21 days after initiation of growth under different light conditions. The ratio (%) in total weight and the ratio (%) with respect to the fresh weight (g) of dry weight (g) are shown.

The ground portion fresh weight and ground portion dry weight in test group 1 resulted in a higher ratio of assimilation engines than in test group 2 group. In addition, in the test group 4, the ratio of the assimilation engine was higher in the ground fresh weight than the test group 5. This result is consistent with the result of the growth promotion of the leaf part in the test group 1 and the test group 4 shown in Table 4, and the observation result of the growth state in FIG.

C. Theorem

From the results of this test example, it was shown that alternating irradiation of red light and blue light promotes plant growth. In addition, it was shown that the above irradiation promotes the growth of the leaves but does not promote the growth of the stems. It became clear that this effect was not reproduced under simultaneous irradiation of red light and blue light or either alone irradiation, but obtained only by alternate irradiation of red light and blue light.

The LED lamp for plant cultivation according to the present invention can perform the execution method in a relatively simple construction by using an existing fluorescent lamp mechanism, ballast or commercial power supply as it is. Therefore, the LED lamp for plant cultivation can be suitably used in plant plants such as leafy vegetables, fruits and grains because it promotes plant growth at low cost and increases the number of harvests and yields per unit time.

A, B: Lighting fixture for cultivating plants D: Straight fluorescent lamp fixture
E: Ballast 1: Body
2: terminal 3: red LED element
4: blue LED element 5: circuit board
51: switching circuit 52: timer circuit
6 input unit 7 display unit
10 socket 11 AC / DC converter
12: AC power supply S ₁ : red light illumination step
S ₂ : blue light illumination step C ₁ , C ₂ : cycle

Claims (5)

A main body portion having a straight fluorescent lamp shape and including a red LED element and a blue LED element;
A power supply terminal provided at an end of the main body;
And a switching circuit for switching the current supplied from the power supply terminal to a driving circuit of the red LED element or a driving circuit of the blue LED element to flow. The method of claim 1,
An LED lamp for plant cultivation, comprising a timer circuit for controlling the switching operation of the drive circuit by the switching circuit. 3. The method of claim 2,
An LED lamp for plant cultivation, comprising an input for setting the current supply time to the red LED element and the current supply time to the blue LED element in the timer circuit. The method of claim 3, wherein
An LED lamp for plant cultivation comprising an AC / DC converter inside or outside. 5. The method of claim 4,
The red LED element having a center wavelength of 570 to 730 nm and the blue LED element having a center wavelength of 400 to 515 nm are disposed.

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