KR101389929B1 - Led lamp for plant - Google Patents

Abstract

The present invention relates to a method of manufacturing a fluorescent lighting type LED lighting device for promoting plant growth using an LED chip, and more particularly, to a method of manufacturing a LED lighting device for promoting plant growth, To a method of manufacturing a white LED lighting package similar to natural light.
The LED lighting device of the fluorescent lamp type of the present invention comprises a blue LED chip, a silicate-based LED chip which absorbs the blue light in the diffusion region of the blue light emitted from the blue LED chip and emits light of a wavelength different from that of the blue light A green phosphor, and a nitride-based phosphor that absorbs a part of the blue light and the green light and emits light of a different wavelength band And a red phosphor.
When such a light emitting package is manufactured by a lighting device and irradiated with horticultural crops such as vegetables, it is possible to shorten the cultivation period by promoting the growth of crops, and it is possible to reduce the production cost compared with the lighting made by a simple combination of blue and red LED chips, I can increase the economic efficiency of the plant.

Description

{LED LAMP FOR PLANT}

The present invention relates to a horticultural LED lighting apparatus for artificially illuminating a plant when growing a crop, and more particularly, to a horticultural LED lighting apparatus using a blue light of a blue LED chip as a basic light source and a phosphor for converting the wavelength of the blue light To produce an LED lighting device close to natural light.

White fluorescent lamps, three-wavelength fluorescent lamps, metal halides, high-pressure sodium lamps and LED lamp lights are used as lighting sources for the plant factories. High-pressure sodium lamps have a visible light conversion rate of about 30% But the peak wavelength is 589 nm, and the red and blue wavelengths are small and the efficiency of photosynthesis is low.

Metal halide lamps can be used for close-up illumination, but the effective photosynthetic wavelength is about 20% unsuitable. White fluorescent lamps have a short life span and are difficult to maintain.

The LED light can be selected from monochromatic wavelengths and complex wavelengths, so that the effective wavelength of plant photosynthesis is as high as 91%, the heat of illumination is small, and the life span is long, which is suitable for use in agriculture but is expensive. The specific monochromatic light of LED illumination can perform functions such as photosynthesis promotion, regulation of flowering, enhancement of coloring, increase of sugar and saponin, and inhibition of fungus generation. In the present invention, the main peak of 610 to 700 nm and the sub peak of 400 to 470 nm To produce light similar to natural light of 380 to 700 nm in visible light, and to promote the growth of crops using this lighting device.

LED lamps have been attracting much attention recently in the field of biotechnology such as plant factories and utilize LED lamps as a light source to induce photosynthesis of crops and promote growth in plants or plant factories.

An invention for promoting plant growth using such an LED lamp is disclosed in Korean Patent No. 10-879711. In the above invention, a plurality of LEDs for generating red light and blue light are provided, and red light and blue light are separately emitted to promote plant growth.

However, since such a structure is limited to the wavelengths of red light and blue light, it is only effective for a certain type of plant growth, so that the growth of horticultural crops may not be uniform.

<Influence of spectrum of light wavelength on crops> Wavelength (nm) Ray type For main work
UV-rays 100-280 UV-A Disinfecting kitchen appliances, harmful to human body 280-315 UV-B Plant growth inhibition and morphological changes 315-380 UV-C Strengthen antioxidants, pigment formation



Thorn
beam 380-400 purple The shortest wavelength visible light, strengthened antioxidants 400-420 Indigo Promoting crop growth 420-470 blue Influence of crop shape and growth,
Flowering induction, photosynthesis effective 470-570 green Safety light, photosynthetic effective 570-610 yellow Photosynthesis Effective, Pest Avoidance 610-650 Orange Growth promoting action, photosynthesis effective 650-700 Red Promotion of growth, effective photosynthesis, inhibition of leptin
infrared ray 700-800 Near infrared Promoting smooth muscle growth (stem height), inhibiting germination 800 or more Far infrared ray thermic rays

It can be seen that the effect on the crop varies depending on the spectrum of the visible light shown in Table 1 above. The blue color of 400 to 420 nm accelerates the growth of the crops. The blue color of 420 to 470 nm inhibits the growth of the crops, induces flowering, and the green of 470 to 570 nm plays an effective role in photosynthesis. Also, the orange color of 610 ~ 650nm promotes the growth of crops, and the red color of 650 ~ 700nm is effective light for photosynthesis, which promotes the growth of the crops and suppresses the growth of the crops.

 <Light requirement and cultivation period per crop> Item unit rice Strawberry Lettuce tomato During re-ventilation Work 100 90 30 90 PPFD
(Photon) μmolm ^-2 / day 800 300 200 600 Daily lighting time hour / day 12 16 16 12 Daily photosynthetic rate μmolm ^-2 / day 34.6 17.3 11.5 25.9

In Table 2, when the value of PPFD (Photosynthetic Photon Flux Density) is increased, the daily photosynthesis amount is greatly increased. Therefore, a lighting device with a high photon density promotes the photosynthesis of crops and promotes the growth of crops.

<Growth effect of crops by light source (as of 25 days after lettuce planting)>

In Table 3, growth and vitamin content of lettuce were determined after 25 days from sunlight, LED lighting, and fluorescent lamps. As shown in the above Table 3, the length of live weight, height and leaf length of LED lighting is much larger than that of sunlight and fluorescent lighting, and the vitamin content is also greatly increased.

When plants are irradiated with red light and blue light as in the conventional method, the reflection color of the plant, which is felt by human vision, appears to be similar to brown or purple depending on the luminance of blue light and red light. It is also difficult to judge the effectiveness of plant growth when blue light and red light alone are illuminated, although the effectiveness of plant growth is judged visually by observing plant growth when cultivating crops. When red light is strongly irradiated, the fatigue of the worker increases in the cultivation area and it becomes a factor to damage the mental stability. Green LEDs are used to overcome these drawbacks, but green LEDs are not economical because they are expensive.

In the present invention, the blue light is used as an excitation light source, the red phosphor and the green phosphor are mixed in a transparent silicone sealing material in a weight ratio and packaged in a single light source body, and blue light and green phosphor excited from the red phosphor, The green light is emitted so that the green light is emitted, thereby realizing a light spectrum similar to that of natural light, thereby solving the problems described above.

In the emission spectrum form (FIG. 1C) disclosed in Korean Patent No. 10-1050504, the first peak is in the region of 450 nm and the second peak is in the region of 600 nm. However, since the LED chip using the phosphor of the (Ca (1-x) Mx) AaBbSs: Eu2, Q series which is the red phosphor represented by the above-mentioned conventional art can not actually realize the peak of 650 nm, A phosphor was used to fabricate an LED chip that achieves a peak at 650 nm.

In the present invention, a red phosphor and a green phosphor are used to manufacture an LED chip having light emission characteristics similar to natural light as shown in FIG. 1A.

Korean Patent Registration No. 10-0984273 2010.09.20. Korean Patent Registration No. 10-0639532 2006.10.23.

In conventional horticultural farms, electronic fluorescent lamps, incandescent lamps, metal halide lamps, sodium lamps and mercury lamps are used in the light sources such as MH, sodium lamp, mercury lamp, and three-wavelength LED lighting plant lighting apparatus. In order to supply electric power to a wide cultivation space, such a conventional lighting apparatus must be enlarged to a large scale, and the lighting apparatus is always exposed to a high temperature and high humidity environment. Therefore, there is a great risk of electric shock during the operation of replacing the LED lamp. There is a problem in that it is not easy to replace the LED lamp installed in a high position such as a ceiling. However, unless the LED lamp that has reached the end of its life is replaced at the right time, the crop growing under the LED lamp is slow in growing, lacking in light quantity, and appearing in the early stage of the emergence of flower buds,

Further, in the conventional lighting apparatus using an LED lamp for promoting plant growth, there is a problem in that installation, control, and management are complicated by providing a plurality of LED lamps in one package.

An object of the present invention is to provide an LED lighting device for plant growth, which can easily manage and grow a variety of crops with low power consumption.

It is another object of the present invention to provide a converterless LED lighting device which is supplied with an external AC power and emits light without a separate converter for DC driving in order to operate the LED lamp. Generally, a converter that drives an LED lamp is known to have a life span of about 30,000 hours, which is very expensive to maintain. In the present invention, the lifetime of the LED lamp is increased three times or more by eliminating the converter necessary for driving the LED lamp and implementing a circuit technique using an external AC power source.

Further, the LED lamp of the present invention can enhance the growth of crops and improve the energy efficiency to 80% as compared with the conventional incandescent lamps, electronic fluorescent lamps, down light type conventional lamps, metal lamp type fresh lamps, To about 40% by weight of the total weight of the horticultural crop.

In the present invention, in order to provide an LED lighting device close to natural light, a single blue light is used as an excitation light source, and a green phosphor and a red phosphor are combined to produce a light source that emits green light as well as red light.

The LED lighting apparatus for horticulture of the present invention is made of a plurality of LED chips coated with the phosphor, and each of the LED chips is connected to a power source to generate light in a plurality of different wavelength regions. The LED illumination device emits a light source to a visible light region and a near infrared region. The main peak is 640 to 690 nm, and the bulk is 440 to 460 nm.

The phosphor used in the LED lighting apparatus of the present invention is an LED lighting apparatus similar to natural light, while the excited light emitted from the light emitting layer of the LED chip and the excitation light transmit green phosphors and red phosphors having different wavelengths.

The structural formula (I) below relates to a nitride phosphor which emits the red light.

???????? Me ₂ -xR x Si ₅ N ₈ -yF ₃ y (I)

The structural formula of (II) below is a structural formula of a silicate phosphor emitting green light.

Chemical formula: BawSrxCaySiO ₄ : zEu (II)

The present invention is to make an LED chip using the nitride phosphor and the silicate-based phosphor to emit light of a wavelength that promotes crop and plant growth.

The nitride phosphor and the silicate phosphor that are applied to the LED chip are mixed in a weight ratio of 1: 2: 1 to 2: 2, and an optimized sRGB is in a range of 1.2: 1.8: 1.3 to 1.5.

INDUSTRIAL APPLICABILITY The LED lighting device of the present invention comprises a nitride-based phosphor which absorbs blue light emitted from an LED chip, green light of a silicate-based phosphor that emits light of a different wavelength band from the blue light, and a part of the blue light and green light to emit light of a different wavelength band The red light is mixed to emit white light similar to natural light.

In the structure of the lead-type LED chip utilizing the silicate-based fluorescent material and the nitride-based fluorescent material of the present invention, a reflector structure 8 is formed inside the plastic frame 7, and a blue LED chip 1 is laid in the center portion . The blue LED chip is electrically connected to an anode lead 2 and a cathode lead 3 by an Au wire and a green phosphor and a red phosphor are formed on the blue LED chip 1 And then molded into a mixed mold resin layer (6).

As described above, in the horticultural LED lighting apparatus according to the present invention, a light emitting chip (LED chip) molded with a phosphor emitting light of various wavelengths is provided in a single illumination package. Accordingly, the manufacturing cost can be reduced by 35% or more, the integration degree can be improved by 44% or more, and the assembly cost can be reduced by 50% as compared with a case where a plurality of chips emitting light of a single wavelength are installed for each wavelength. In addition, since one type of chip can generate light of various wavelengths, it is possible to reduce installation area, production cost, and power consumption. Also, as mentioned in the Background Art, by using the illumination device of the present invention in comparison with general illumination devices using blue and green LEDs, it is possible to directly detect the reflection index green of the leaf vegetables to produce the growth condition of the cultivated plants and the flower color of the flowering plants It can be immediately judged in the field, and contributes to the mental stability of the producers who produce the cultivars compared to the blue-green lighting devices which are strong in purple color.

INDUSTRIAL APPLICABILITY The LED lighting device for promoting plant growth according to the present invention generates light of a color close to that of an incandescent lamp by appropriately combining light of various wavelengths generated from a chip molded with a phosphor to generate light of a wavelength optimum for plant growth .

FIG. 1A shows the light efficiency of the plant-specific LED spectrum of the present invention
1B is a graph showing spectra of blue light and red light of the present invention
1C is a graph showing the relationship between the light intensity
FIG. 1D shows the emission spectrum of a fluorescent lamp of the present invention
1E is a graph showing the emission spectrum
2 is a detailed view of an LED lighting device according to an embodiment of the present invention;
Fig. 3 is a photograph showing the reflection color of lettuce cultured using a conventional fluorescent lamp
Fig. 4 is a photograph showing the reflection of the lettuce cultured with the blue and green LED lights of the present invention

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical meanings and concepts of the present invention.

The embodiments described in the present specification and the configurations shown in the drawings are preferred embodiments of the present invention and are not intended to represent all of the technical ideas of the present invention and thus various equivalents and modifications Can be.

FIG. 1A is a graph showing the light efficiency of the plant-exclusive LED spectrum of the present invention, in which the main peak is near 650 nm and the peak is near 450 nm. FIG. 1B is a graph showing the spectrum of blue light and red light of the present invention, Blue light shows red light emission around 650 nm, and FIG. 1C is a graph showing light intensity according to the wavelength of conventional white LED light. FIG. 1D is a graph showing the emission spectrum of the fluorescent lamp of the present invention, showing strong emission at 440 nm, 550 nm, and 610 nm, and FIG. 1e is a graph showing the emission spectrum of a red phosphor.

FIG. 2 is a detailed view of a single LED chip according to the embodiment, in which the LED chip 1 is located inside the plastic frame 7, the LED chip is connected to the anode lead 2 and the cathode lead 3, The phosphor layer is coated with the mixed mold layer 6.

FIG. 3 is a photograph of a lettuce grown using a conventional fluorescent lamp, and FIG. 4 is a photograph of a lettuce grown by the blue and green LED lighting of the present invention.

Various methods have been developed for promoting the growth of crops, flowers, fruit trees, and the like by means of the conventional LED lighting apparatuses, such as vinyl house cultivation and hydroponic cultivation. In the present invention, green and red phosphors And a mixed color light source which emits light is mixed.

The plant growth-promoting LED illumination device of the present invention emits light to a visible light region and a near-infrared light region. The main peak generates light having a wavelength of 640 to 690 nm, preferably 650 nm, and has a bulk of 440 to 460 nm, And to manufacture an LED lighting device for promoting plant growth using an LED chip that generates light of a wavelength.

The LED lighting device includes a blue LED chip and a silicate phosphor that absorbs the blue light in a diffusion region of blue light emitted from the blue LED chip to emit light having a wavelength different from that of the blue light, Nitride that emits light of different wavelengths And a phosphor. The light emitted from the LED illumination device has a white light emission spectrum similar to natural light due to the mixture of blue light emitted from the blue LED chip, green light emitted from the green phosphor, and red light emitted from the red phosphor.

The structural formula (I) below relates to a nitride phosphor which emits red light.

Me ₂ -xR x Si ₅ N ₈ -yF ₃ y (I)

In the above structural formula, Me is an alkaline earth metal, R is a rare earth metal, Si is a silicon element and N is a nitrogen element, and satisfies 0 <x <1 and 0 <y <1.

More specifically, it is preferable that 0 <x <0.3 and 0 <y <0.5 in the above structure.

The nitride phosphor has an average size of powder size of 10 탆 or less, preferably 0.01 to 2 탆.

The nitride phosphor powder has improved physical properties and optical properties of rare earth metal-doped alkaline earth metal silicon nitride phosphor powders (Me ₂ -xR x Si ₅ N ₈ -yF ₃ y (0 <x <0.5, 0 <y <1) Fluorine source (FS) containing a small amount of an inorganic fluorine salt is further added to the reaction mixture to give a fluorine-doped nitride-based phosphor powder. The nitride-based fluorescent material has a small particle size, has a large total surface area, has improved chemical characteristics, and strongly absorbs UV and blue light and can efficiently convert the red light into a red light. In addition, since there is no settling in the LED chip, it is possible to uniformly form a layer, which can be usefully used in an LED lighting device for gardening.

The structural formula (II) below is a structural formula of a silicate phosphor which emits green light.

Structural formula: BawSrxCaySiO ₄ : zEu (II)

In the above formula, w + x + y + z = 2, and the silicate phosphor has a spherical particle shape, a polygonal shape or a plate shape, and the size ranges from 0.1 to 5 mu m.

The silicate phosphor emits green light and the silicate phosphor is a silicate according to the formula (II), Ce-doped lutetium-containing garnet, Eu-doped sulfoselenide, thiogallate and / or Ce- and / Or phosphors containing Eu-doped nitrides.

The LED chip is made of the nitride phosphor and the silicate-based phosphor to emit light of a wavelength similar to that of natural light useful for growing crops and plants. At this time, when the nitride phosphor is integrated in the LED chip emitting blue light to emit red light, and the silicate-based phosphor is accumulated thereon, green light is emitted, and light of these wavelengths is advantageous for plant growth.

The nitride phosphor and the silicate phosphor that are applied to the LED chip are mixed in a weight ratio of 1: 2: 1 to 2: 2, and an optimized sRGB is in a range of 1.2: 1.8: 1.3 to 1.5.

A silicate phosphor emitting a blue light emitted from the LED chip of the present invention, a silicate phosphor emitting light of a different wavelength band from the blue light, that is, a green light, and a nitride phosphor absorbing a part of the blue light and the green light to emit light of a different wavelength band, The illumination device emits white light similar to natural light.

The nitride phosphor powder is mixed with an appropriate amount of a polymer resin to confirm the characteristics of the LED chip and is used together with an InGaN-based material used for blue light to manufacture a light emitting device. In this case, the phosphor of the present invention can be packaged on the surface of a light-emitting element including a UV-blue light source.

The plant growth-accelerating LED illumination device of the present invention emits light to a visible light region and a near-infrared light region, and the main peak generates light having a wavelength of 640 to 690 nm, preferably 650 nm, and has a bulk of 440 to 460 nm, And emits white light similar to natural light including light having a main peak and a sub peak although it contains light having a wavelength of 450 nm.

In the structure of the lead-type LED chip utilizing the silicate phosphor and the nitride phosphor of the present invention, the reflector structure 8 is formed inside the plastic frame 7, and the blue LED chip 1 is laid in the center thereof. The blue LED chip is electrically connected to an anode lead 2 and a cathode lead 3 by an Au wire and a green phosphor and a red phosphor are formed on the blue LED chip 1 And then molded into a mixed mold resin layer (6).

The mold resin is formed by mixing a green phosphor and a red phosphor in a liquid epoxy or silicon, and the mold resin is molded on a blue LED chip or an LED chip emitting green light.

The structure of the horticultural LED lighting apparatus of the present invention is arranged at a distance from each other on a plant, and is composed of a socket terminal in which a power source unit (built-in or external type) and a light source unit are electrically connected.

The hood lighting LED lighting apparatus of the present invention is not limited in structure and form, and typical types include a bulb type, a fluorescent lamp type, a down light type, a PAR type, a fresh lamp, an intuitive lamp, a metal halide lamp, .

2. Description of the Related Art Generally, a fluorescent lamp type LED lighting apparatus is composed of a socket and a plurality of bases which are plugged to the socket terminals and electrically connected to the socket terminals and are separately connected to the fluorescent lamp sockets, and are electrically connected to the bases. And a power supply means for supplying an external power applied through the bases and the fluorescent lamp sockets to the blue light emitting LED chip and the LED chip molded by the phosphor is formed.

Shaped circuit board which is located between the bases to electrically arrange the LED chips and is electrically connected to the power supply means to supply the power of the power supply means to the LED chips, An LED chip which is electrically arranged in one or more rows on a substrate and is configured to emit light by power supply of a power supply means supplied through a circuit board and a cylindrical tube whose both ends are opened, The fluorescent lamp type LED lighting device constituting a fluorescent light type LED lighting device which is inserted into the fluorescent lamp socket by integrally joining the left and right ends with the bases while inserting the arranged circuit boards therein.

The light source body is surface-mounted on a printed circuit board provided with a power input circuit and is attached to a heat radiating plate of a heat radiation designed lighting fixture, and a lighting apparatus including a cover of a diffusion plate type or a transparent type is provided according to the environment.

The power supply means includes a constant current type converter or a converterless.

A packing member for further preventing the inflow of water into the socket terminal by providing water tightness between the tube and the inner circumference of the cylindrical bodies is additionally provided on the outer circumference of the tube .

And diffusion protrusions for increasing the efficiency of light are further protruded from the inner circumference of the tube by diffusing light emitted from the LED.

The portion of the tube to which the light is irradiated is made transparent, and the opposite portion is made opaque.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. In addition, it is a matter of course that various modifications and variations are possible without departing from the scope of the technical idea of the present invention by anyone having ordinary skill in the art.

1 Blue light LED chip 2 Anode lead
3 Cathode lead 5 Transparent resin layer
6 Phosphor mold layer 7 Plastic frame
8 reflector

Claims (5)

In the LED lighting apparatus for gardening,
The LED lighting device includes an LED chip for emitting blue light; And
The LED chip for emitting the blue light is molded with a mold resin mixed with a silicate phosphor to emit green light,
The LED chip on which the silicate phosphor is molded is molded with a mold resin mixed with a nitride phosphor to absorb a part of the blue light and the green light to emit red light to emit white light by mixing a blue light, a green light and a red light,
A base having a plug terminal on which the LED chip is arranged and electrically connected to a socket terminal, a circuit board on which power is supplied by the power supply means to the LED chip, and a power supply, Emitting,
And a packing member for blocking inflow of water into the socket terminal is provided.
delete delete The method according to claim 1,
Wherein the LED illumination device comprises a diffusing projection for diffusing light emitted from the LED chip to increase light efficiency.
The method according to claim 1 or 4,
Wherein the LED illumination device is formed in any one of a bulb type, a fluorescent type, a down light type, a PAR type, a fresh lamp type, an intuitive type lamp, a metal halide lamp, and a factory type.

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