KR102604933B1 - Lighting device for plant growth - Google Patents

Abstract

Disclosed is a plant growth lighting device. The present invention converts the blue wavelength light source of an LED device into UVA of 400 nm or less, which has two wavelength peaks between 340 nm and 470 nm wavelengths, by utilizing a light conversion material with UV light conversion properties disposed in a layer surrounding the lens portions of the LED device. It includes a light conversion layer in which a first wavelength peak and a blue second wavelength peak with lower intensity than the first wavelength peak are formed in a bimodal shape and are converted into external output light of the lamp having a wide half width.

Description

Lighting device for plant growth}

The present invention relates to a plant growth lighting device that improves the growth environment of crops by including UVA wavelengths of 400 nm or less and blue wavelengths between 340 nm and 470 nm, while providing a cultivation environment similar to sunlight conditions.

Lighting devices are used for plant growth. Lighting devices for plant growth include incandescent lamps, fluorescent lamps, and general LEDs, but incandescent lamps have the problem of low energy efficiency, and fluorescent lamps have the limitation of low energy efficiency because they emit little red and blue wavelength light and have a lot of green wavelength light. Recently, plant growth lighting devices with monochromatic wavelengths, low power consumption, excellent responsiveness, and long lifespan have been used as lighting devices for plant growth. Plants grow through photosynthesis, and methods of providing light used for photosynthesis through lighting devices are widely used. Previously, light containing blue, red, and green wavelengths was provided to grow plants. Blue wavelengths were used to induce flowering, and red and infrared light was used to promote growth and grow stems. . However, since green wavelengths are reflected from the leaves and stems of plants, they do not have a significant effect on growth, so there is a problem of energy waste when providing light containing green wavelengths.

Meanwhile, in order to solve the above problem, a 'lighting device' is proposed in Domestic Patent Publication No. 10-1908239 (Patent Document 1). The technology of Patent Document 1 is a light source that outputs light and a light source from the light source. It includes a light exit area that outputs output light to the outside based on light, and the peak of the wavelength of the output light output from the light exit area is a first peak, a second peak, and a third peak, as shown in FIG. 1. The first peak is a wavelength band of blue light, the second peak and the third peak are induced to represent a wavelength band of red light, and are emitted as red wavelength light having two peaks through a lighting device to promote plant growth. is being promoted. Meanwhile, as abnormal climate and desertification progress, interest in advanced agricultural production methods that are stable and convenient to respond to environmental changes is increasing. Accordingly, research is being conducted on multi-purpose production methods in an environment independent of the external climate through crop cultivation in facilities such as glass greenhouses, houses, and smart farms, and related technologies include 'Horticulture' in Domestic Patent Publication No. 10-1783368. LED lighting assembly (patent document 2)’, ‘Method and device for promoting plant growth and development using near-infrared rays and visible light (patent document 3)’ in Korean Patent Publication 10-2017-0139551, and Korean Patent Publication 10-2017 -0110171 is proposed as ‘Quantum dot light-emitting diode that improves the growth of photosynthetic organisms (Patent Document 4).’ The present applicant, the inventor, is developing a new plant growth method that improves crop growth by controlling the wavelength conditions of plant growth lighting, which is an essential element in implementing automation and precision in agriculture, while providing a crop cultivation environment similar to that in sunlight. We propose a lighting device.

Patent Document 1. Domestic Registered Patent Publication 10-1908239 (announcement date: December 28, 2018) Patent Document 2. Domestic Registered Patent Publication 10-1783368 (announcement date: October 10, 2017) Patent Document 3. Domestic Patent Publication 10-2017-0139551 (published on December 19, 2017) Patent Document 4. Domestic Patent Publication 10-2017-0110171 (published on October 10, 2017)

One of the technical problems to be solved by the present invention is to provide a plant growth lighting device with a wide half width between wavelengths of 340 nm and 470 nm.

One of the technical problems to be solved by the present invention is to improve the growth condition of crops by forming two wavelength peaks between 370nm and 410nm wavelengths, a UVA wavelength peak of 400nm or less and a blue wavelength peak of relatively low intensity in a bimodal shape. At the same time, the aim is to provide a plant growth lighting device that adjusts the crop cultivation environment to be similar to solar conditions.

The above objectives are, according to the present invention, a lighting environment suitable for plant growth is,
An LED lens unit individually attached to an LED element, and a blue wavelength light source of the LED element are converted into two wavelengths between 340 nm and 470 nm by utilizing a light conversion material with UV light conversion properties disposed in a layer surrounding the LED lens units. A first wavelength peak of UVA of 400 nm or less, which is a wavelength peak, and a second wavelength peak of blue with a lower intensity than the first wavelength peak are formed in a bimodal shape, comprising a light conversion layer that converts the light into external output light having a wide half width. It can be achieved from a plant growth lighting device characterized in that.
According to an embodiment of the present invention, a plant growth lighting device may be configured to induce emission of the light wavelength by placing a plurality of LED elements on a flexible substrate that can be bent or bent.

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According to an embodiment of the present invention, the plant growth lighting device uses any one light conversion material selected from phosphors or quantum dots to form a first wavelength peak of UVA below 400 nm among two wavelength peaks between 340 nm and 470 nm wavelengths. This can be achieved from a plant growth lighting device that processes and attaches to the light path to induce the light to emit the light wavelength.

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According to an embodiment of the present invention, the light conversion layer may be constructed by attaching a film containing a light conversion material.

According to an embodiment of the present invention, the light conversion layer may include a concave lens portion individually corresponding to the LED elements to control light diffusion.

According to an embodiment of the present invention, the light conversion layer may include a convex lens portion individually corresponding to the LED elements to control light diffusion.

According to an embodiment of the present invention, the light conversion layer may be composed of a light conversion film containing any one selected from light scattering particles or beads to control light diffusion.
According to an embodiment of the present invention, the light conversion layer may be configured to be attachable and detachable from the plant growth lighting device.

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The present invention has the effect of providing a light wavelength advantageous for plant growth lighting by supplying the external output light of the lamp with a wavelength having a wide half width through UVA and blue wavelengths between 340 nm and 470 nm.

In addition, the wavelength of the external output light of the lamp is between 340nm and 470nm, with a UVA wavelength peak of 400nm or less and a blue first wavelength peak of lower intensity forming a double peak, improving the growth condition of crops and improving the cultivation environment of crops. It has the effect of providing a plant growth lighting device that is controlled to be similar to solar conditions.

Figure 1 is a diagram showing the wavelength of light output through an existing lighting device.
Figure 2 is a diagram showing the Emerson synergistic effect required for crop growth lighting.
Figure 3 is a diagram showing an example of growing plants using a lighting device.
Figure 4 is a diagram showing the wavelength of light output through a plant growth lighting device according to an embodiment of the present invention. (a) (b) (c) are comparative examples showing that the peak of the light wavelength output through each plant growth lighting device can be partially adjusted.
Figure 5 is a diagram explaining the light wavelength output through the plant growth lighting device according to an embodiment of the present invention.
Figure 6 is a diagram showing the planar arrangement structure of LED elements constituting a plant growth lighting device according to an embodiment of the present invention.
Figure 7 (a) (b) (c) (d) shows various examples of light conversion layers constituting a plant growth lighting device according to an embodiment of the present invention. (a) is an example of a film-type light conversion layer, (b) is an example of a concave lens-type light conversion layer, (c) is an example of a convex lens-type light conversion layer, and (d) is an example of a scattering particle-type light conversion layer.
Figure 8 is a diagram showing the lighting state of the plant growth lighting device according to an embodiment of the present invention.
Figure 9 is an example showing the distribution of anthocyanins in red lettuce grown under monoblue wavelength LED lighting.
Figure 10 is an example showing the distribution of anthocyanins in red lettuce grown in the open field with sunlight.

Hereinafter, the details of the 'plant growth lighting device' according to a preferred embodiment of the present invention will be described in detail with reference to the drawings.

1 is a diagram showing the wavelength of light output through the lighting device disclosed in Patent Document 1. (a) is a diagram showing the wavelengths of light divided by peaks. (b) is a diagram showing the wavelengths of light divided into blue and red.

Referring to FIG. 1, the wavelength of output light has at least three peaks. Blue wavelength light may be output by a blue light source, and red wavelength light may be output through other light sources. The output light may have first to third peaks. The half width of red light can be adjusted to be larger than the half width of blue light by the light having the second peak and the light having the third peak.

And, the intensity of the first peak may be greater than the intensity of the second peak or the intensity of the third peak.

Flowering is induced by blue wavelength light, and plant growth can be promoted by red or near-infrared wavelength light.

When the red or near-infrared wavelength light is simultaneously irradiated to plants in a form having two peaks, it has an Emerson synergistic effect as shown in FIG. 2.

Figure 2 is a diagram showing the Emerson synergy effect. Referring to Figure 2, the sum of the photosynthetic rates obtained by simultaneously irradiating light with two peaks is greater than the sum of the photosynthetic rates obtained by independently irradiating red light with a relatively long wavelength of 700 nm and red light with a relatively short wavelength. In other words, rather than growing plants by irradiating different red lights at intervals using different lighting devices, the growth rate of plants can be improved when red lights with different wavelengths are irradiated simultaneously through a single lighting device. Able to know.

Figure 3 is a diagram showing an example of growing plants using a lighting device.

Plant growth lighting according to these existing lighting devices has one peak between 400 and 500 nm in the blue wavelength and two or more peaks in the red region, so an Emerson synergistic effect can be expected, but this does not affect the overall growth of the plant. Since it does not exceed the range of general plant growth lighting, which is divided into the wavelength range of 400-500 nm blue light and 600-690 nm red light that promotes photosynthesis in plants, there are limitations in providing new plant growth effects.

Accordingly, in relation to the wavelength that promotes photosynthesis in plants, where the well-known Emerson synergy effect can be expected, there is a need for a lighting device that can be optimized for photosynthesis in plants by limiting unnecessary wavelengths and improving light efficiency.

Figure 4 is a diagram showing the wavelength of light output through a plant growth lighting device according to an embodiment of the present invention. Here, (a) (b) (c) are comparative examples showing that the peak of the light wavelength output through the plant growth lighting device can be partially adjusted.

When comparing the light wavelength output through the plant growth lighting device according to an embodiment of the present invention with the light wavelength output from the existing lighting device, the existing light wavelength has one peak between 400 and 500 nm in blue and a peak in the red region. It is a wavelength with two or more peaks, and the light wavelength according to the present invention has two wavelength peaks between 340nm and 470nm wavelengths, a first wavelength peak of UVA between 380nm and 400nm wavelengths, and a first wavelength peak of UVA between 420nm and 420nm, as shown in Figure 4. A blue second wavelength peak with lower intensity than the first wavelength peak between the 440 nm wavelength is formed in a bimodal shape, so that a plant growth lighting device of external output light from a lamp having a wide full width at half maximum can be provided.

Figure 5 is a diagram explaining the light wavelength output through the plant growth lighting device according to an embodiment of the present invention.

Referring to Figure 5, in relation to the wavelength that promotes photosynthesis in plants, if the absorbance of plants is divided into chlorophyll (A), chlorophyll (B), and beta carotene (C), the absorbance of chlorophyll (A) is approximately high around 350 nm. It rises at an inclination angle, reaches the highest peak around approximately 430 nm, then descends at a steep inclination angle, forming a low point around approximately 450 nm, and then rises again around approximately 640 nm, reaching a peak with an intensity about 1/3 lower than the highest peak intensity. After reaching and then descending, it forms a low point around approximately 680nm, and the absorbance of chlorophyll (B) rises at approximately a high inclination angle around 400nm, reaches the highest peak (A) around approximately 440nm, and then descends at a steep inclination angle. After forming a low point around 470 nm, it can be seen that a peak with an intensity lower than the highest peak (A) is formed again at approximately 610 nm to 650 nm. Unnecessary wavelengths are limited and the light wavelengths necessary for plant growth are reduced. This is an example to explain that light efficiency can be improved by forming.

As shown in FIGS. 4 and 5, the plant growth lighting device to be provided by the present invention is a plant growth lighting device that provides a lighting environment suitable for plant growth, and uses a blue wavelength LED light source between 340 nm and 470 nm wavelength. A lighting fixture with two wavelength peaks, a first wavelength peak of UVA between the wavelengths of 380 nm and 400 nm, and a second wavelength peak of blue with lower intensity than the first wavelength peak between the wavelengths of 420 nm and 440 nm, formed in a bimodal shape and having a wide half width. The aim is to provide a plant growth lighting device that improves the growth of crops by converting it into external output light and at the same time implements light conversion so that the crop cultivation environment is similar to the conditions under sunlight.

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The plant growth lighting device according to the present invention can utilize quantum dots (QDs) to generate light wavelengths with more diverse wavelengths than existing LEDs. Quantum dots (QDs) are ultrafine semiconductor nanoparticles and are a topic of interest in the field of nanochemistry. When the size of quantum dot particles decreases to a few nanometers, the electro-optical properties of these particles change significantly. When electricity or light is applied to various types of quantum dots, light with a specific frequency is emitted depending on the size, shape, and material of the particles. As a result, luminous colors in various areas can be realized and power consumption can be reduced. . In particular, quantum dots can efficiently change the frequency and wavelength at which light is absorbed or emitted by controlling only the size of the particle without changing the type of material.

When LED light is irradiated to plants or crops using quantum dots, it can more easily generate a variety of wavelengths than existing LEDs, so it can be effectively used to improve the growth efficiency of crops.

The present invention uses an LED device to irradiate plants with light of different wavelengths depending on the state of the plants through wavelength control using light conversion materials, such as quantum dots or phosphors, thereby irradiating the plants with light. It can be configured as a plant growth lighting device that can dramatically improve the growth effect of plants.

Figure 6 is a diagram showing the planar arrangement structure of LED elements constituting a plant growth lighting device according to an embodiment of the present invention.

Figure 7 (a) (b) (c) (d) shows various examples of light conversion layers constituting a plant growth lighting device according to an embodiment of the present invention. (a) is an example of a film-type light conversion layer, (b) is an example of a concave lens-type light conversion layer, (c) is an example of a convex lens-type light conversion layer, and (d) is an example of a scattering particle-type light conversion layer.

As shown in Figures 4 to 7, the plant growth lighting device 100 according to the present invention is arranged on a flexible substrate 120 that can bend or bend a plurality of LED elements 110 to emit light. It can be configured to do so.

In addition, it may be configured to include a light conversion layer 200 that is disposed on the upper surface of the LED device 110 and includes a light conversion material that converts the light wavelength emitted from the LED device 110.

That is, in a plant growth lighting device that implements the wavelength of plant growth lighting, an LED element 110 that forms a blue wavelength is disposed, and the light wavelength emitted from the LED element 110 is displayed on the upper layer of the surface of the LED element 110 in FIG. 4. And as shown in Figure 5, there are two wavelength peaks between 340nm and 470nm wavelengths, a first wavelength peak of UVA between 380nm and 400nm wavelengths, and a blue peak with lower intensity than the first wavelength peak between 420nm and 440nm wavelengths. The second wavelength peak is formed in a bimodal shape and may be configured to include a light conversion layer 200 that converts the light into external output light having a wide half width.

The plant growth lighting device 100 can be converted to include one UVA wavelength peak below 400 nm out of two wavelength peaks between 340 nm and 470 nm. In this case, crop growth can be improved and the crop cultivation environment can be adjusted to be similar to solar conditions.

In addition, the plant growth lighting device 100 processes a light conversion material selected from phosphors or quantum dots with UV light conversion characteristics in order to form a UVA wavelength of 400 nm or less between 340 nm and 470 nm wavelengths and places it in the optical path. It can be configured to implement a complex wavelength of blue light by attaching it.

Additionally, the plant growth lighting device 100 may be configured to emit light by placing a plurality of LED elements on a flexible substrate that can be bent or curved.

Here, the flexible substrate 120 is a material that can bend or be bent, and may be composed of a substrate or film on which the LED elements 110 can be uniformly arranged. A printed circuit board (PCB), etc. may be applied for electrical mounting of the LED element 110. The flexible substrate 120 may be made of a flexible material so that the point light source substrate by the LED element 110 can be bent. For reference, a flexible substrate or film can have a wiring pattern freely formed on a flexible insulating substrate made of a polymer such as polyimide, and various devices can be mounted depending on the type of flexible panel for a light source. Generally, it is commercialized or proposed as a flexible printed circuit board (FPCB) or flexible copper clad laminate (FCCL).

Preferably, the material for the flexible substrate 120 of the plant growth lighting device 100 may be selected from PI, PS, PE, PP, etc., and an electrode for supplying power is formed on the flexible substrate 120, and the material is small in size. It can be manufactured in a structure in which the LED elements 110 are arranged at regular intervals.

The LED elements 110 can be directly used as devices that emit specific wavelengths such as 400nm, 450nm, 570nm, 610nm, 620nm, 640nm, 660nm, 710nm, 740nm, 780nm, and 840nm, and are especially used as high-energy short-wavelength LEDs and light conversion materials. It can be configured to convert the wavelength and use it using a light conversion layer 200 using quantum dots and phosphors.

Preferably, the light conversion layer 200 using a light conversion material has a first wavelength peak of UVA of 400 nm or less between the wavelengths of 340 nm and 470 nm and the first wavelength peak in order to improve the growth effect according to the growth and growth state of the crop. The wavelength having a lower intensity blue second wavelength peak can be selected and configured to be controlled to a wavelength suitable for plant growth.

The light wavelength of the light conversion layer 200 created through controlling the wavelength of the light conversion material can be manufactured to provide a wavelength suitable for crop growth, and the light conversion layer 200 manufactured in this way can be used as a plant growth lighting device 100. ) It can be configured to be provided by attaching it separately to the body.

In addition, the plant growth lighting device according to the present invention can apply wireless charging technology using a coil manufactured in a pattern format as a power supply method for recyclability, and the rechargeable battery can also supply power using a thin film-type rechargeable battery. It can be configured.

In addition, the plant growth lighting device according to the present invention may be configured by disposing a base film (not shown), and providing the base film with a film-type rechargeable battery (not shown) that supplies power to the LED element 110.

In addition, the plant growth lighting device according to the present invention may be constructed by attaching a protective film (not shown) to the lower layer of the base film, and the protective film includes a controller (not shown) that controls the light emission of the LED element 110. , and may be configured to include a wireless power receiver (not shown) that receives power wirelessly.

Additionally, in the plant growth lighting device according to the present invention, the light conversion layer 200 may be constructed by attaching a film containing a light conversion material.

Additionally, in the plant growth lighting device according to the present invention, the light conversion material forming the light conversion layer 200 may be composed of quantum dots.

Additionally, the plant growth lighting device according to the present invention can be constructed by selecting the light conversion material forming the light conversion layer 200 from phosphors.

In addition, as shown in (b) of FIG. 7, the plant growth lighting device according to the present invention has a light conversion layer 200 with concave surfaces individually corresponding to the LED elements 100 to effectively control light diffusion. It may be manufactured and configured to include a lens unit 210.

In addition, as shown in (c) of FIG. 7, the plant growth lighting device according to the present invention includes a convex lens individually corresponding to the LED elements 110 to control light diffusion of the light conversion layer 200. It may be manufactured and configured to include a portion 220.

In addition, as shown in (d) of FIG. 7, the plant growth lighting device according to the present invention uses any one selected from light scattering particles or beads to control light diffusion in the light conversion layer 200. It may be manufactured by manufacturing a light conversion film 230 containing the light conversion film 230 .

Figure 8 is a diagram showing the lighting state of a plant growth lighting device manufactured according to an embodiment of the present invention.

Differences depending on the presence or absence of ultraviolet wavelengths irradiated to plants are compared as shown in Figures 9 and 10. Figure 9 is an example showing the distribution of anthocyanins in red lettuce grown under monoblue wavelength LED lighting. Figure 10 is an example showing the distribution of anthocyanins in red lettuce grown in the open field with sunlight.

The plant growth lighting device 100 according to the present invention can be controlled to include a first wavelength peak of UVA of 400 nm or less among two wavelength peaks between 340 nm and 470 nm wavelengths. For example, in order to form a UVA wavelength of 400 nm or less, the plant growth lighting device 100 processes a light conversion material selected from phosphors or quantum dots with UV light conversion characteristics and attaches it to the optical path to produce blue light. Complex wavelengths can be implemented.

In addition, the present invention can increase the UVA wavelength or blue light wavelength of 400 nm or less, which is two wavelengths between 340 nm and 470 nm, through wavelength conversion of LED devices or light conversion materials (quantum dots, phosphors, etc.). This may be advantageous in increasing the growth rate of crops according to the effect of increasing PPFD through improvement in light quantity.

In addition, when UVA wavelengths are supplied to crops, they basically have the effect of sterilizing and killing indoor microorganisms by light, and promote the formation of an antioxidant substance called anthocyanin in crops.

When irradiated with ultraviolet wavelengths, anthocyanin synthesis occurs, and the color changes depending on the concentration of hydrogen ions, i.e. pH. When neutral, it usually appears dark purple or dark blue. The more acidic it is, the more red it is, such as purple and red. The more basic it is, the more blue it is, such as blue, green, and yellow.

Anthocyanins are a member of the flavonoid series and are known to have a molecular structure in which two aromatic rings are connected by three carbons and one oxygen.

Anthocyanin is a structure in which one or more sugars are bound to anthocyanidin, and is a component that gives various flower colors to attract pollinators, and also acts as a defense substance to defend plants from herbivorous insects. For example, cyanidin 3-glucoside, a type of anthocyanin, is known to protect cotton leaves from tobacco moth larvae.

The picture below is an example of the molecular structure of anthocyanin.

These anthocyanins are known to have antioxidant, anticancer, and anti-inflammatory effects. All cells engage in metabolic activities, and a large amount of oxygen is required for activity. Cells use oxygen to perform activities, and they emit active oxygen and begin to gradually become oxidized.

In addition, anthocyanin is the most powerful antioxidant among 150 types of flavonoids and is known to inhibit the progression of breast cancer and tumors, help improve night vision and overall vision, and have a blood sugar lowering effect. In particular, in leafy vegetable crops, anthocyanins are clearly identified by color as shown in FIGS. 9 and 10 and are known to be involved in promoting antioxidants, so they can be usefully used to improve the productivity and marketability of crops.

According to the present invention, the advantage of providing a light wavelength advantageous for plant growth lighting is to provide a wavelength with a wide full width at half maximum through the UVA wavelength of 400 nm or less and the blue wavelength among the two wavelengths between 380 nm and 400 nm. there is.

In addition, plant growth lighting improves the growth condition of crops by ensuring that the light wavelength includes the UVA wavelength of 400 nm or less among the two wavelengths between 380 nm and 400 nm, while adjusting the crop cultivation environment to be similar to that in sunlight. There are advantages to providing a device.

The present invention has been described with reference to an embodiment shown in the drawings, but is not limited to the embodiment and can be implemented with modifications and variations without departing from the gist of the present invention, and the modifications and variations are within the technical spirit of the present invention. Included.

100: Plant growth lighting device 110: LED device
120: Flexible substrate 200: Light conversion layer
210: concave lens unit 220: convex lens unit
230: Light conversion film

Claims (10)

LED lens unit individually attached to the LED element
The blue wavelength light source of the LED device is converted into two wavelength peaks between 340nm and 470nm wavelengths, a first wavelength peak of UVA below 400nm, and a light conversion material with UV light conversion properties disposed in a layer surrounding the LED lens parts. A light conversion layer in which a blue second wavelength peak with lower intensity than the first wavelength peak is formed in a bimodal shape and is converted into external output light of the lamp having a wide half width. According to claim 1,
The plant growth lighting device is a plant growth lighting device that induces light to be emitted by placing a plurality of LED elements on a flexible substrate that can be bent or bent. According to claim 1,
The light conversion layer is a plant growth lighting device composed of a light conversion material of either phosphor or quantum dot. According to claim 1,
The light conversion layer is a plant growth lighting device constructed by attaching a film containing a light conversion material. According to claim 1,
The light conversion layer includes a concave lens portion individually corresponding to the LED elements to control light diffusion. According to claim 1,
The light conversion layer includes a convex lens portion individually corresponding to the LED elements to control light diffusion. According to claim 1,
The light conversion layer is a plant growth lighting device composed of a light conversion film containing any one selected from light scattering particles or beads to control light diffusion. According to claim 1,
The light conversion layer is configured to be detachable from the plant growth lighting device. delete delete

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