JP5651302B2 - Light source for plant cultivation - Google Patents

Description

  The present invention relates to a light source for plant cultivation.

  In recent years, plant factories that cultivate vegetables, fruits, flower buds, etc. in an artificial environment have been put into practical use. In plant factories, by irradiating light from an artificial light source, stable and efficient cultivation of plants is possible without being affected by sunlight conditions such as the weather, day and night, and season.

  It has been found that plants do not grow using light of all wavelengths contained in sunlight, but grow using light of a specific wavelength region. Therefore, irradiating a plant with light in this specific wavelength region is an indispensable technique for efficient plant cultivation.

  Conventionally, high-intensity discharge lamps such as metal halide lamps and fluorescent lamps have been used as light sources for plant cultivation, but (1) low power consumption, (2) low heat generation, (3) compact shape, (4) Light emitting diodes are attracting attention because of their advantages such as long life.

  Patent Document 1 describes that chlorophyll (chlorophyll) has light absorption peaks in two wavelength regions near 450 nm in the blue region and 660 nm in the red region, and has almost the same emission peak wavelength as each light absorption peak. A light source for plant cultivation in which a large number of blue light emitting diodes and red light emitting diodes are arranged in a matrix is disclosed.

  Patent Document 2 discloses an LED light source for plant growth that emits two types of light corresponding to two light absorption peaks of chlorophyll from one light emitting diode (LED). In this document, a light source provided with two light emitting regions in one light emitting diode, or a light absorption peak light in the red region is emitted from the light emitting diode body, and a part of this light is used to make blue light. A light source that emits light in the region is described.

JP-A-8-103167 JP 2002-27831 A

  As described above, plants grow using light in two specific wavelength regions that are absorbed by chlorophyll. However, according to recent research, the optimal wavelength of light varies depending on the growth stage of the plant and the type of plant. I understand that.

  In the light emitting diode, the emission peak wavelength can be adjusted by selecting the production material, but the once produced light emitting diode cannot change the emission peak wavelength. The same applies to the light source described in Patent Document 2.

  Therefore, the light source for plant cultivation described in Patent Documents 1 and 2 cannot change the wavelength of the light to be irradiated according to the growth stage or type of the plant. For this reason, in order to change the emission peak wavelength, it must be replaced with another light source for plant cultivation manufactured with different emission peak wavelengths. As a result, it is necessary to prepare a plurality of light sources, and there is a problem that the cost is high and the replacement work is complicated. In addition, manufacturers of light sources for plant cultivation need to manufacture many types of light sources as a whole, and the storage location and management of the manufactured products are complicated.

  This invention was made in order to solve the said subject, and it aims at providing the light source for plant cultivation which can be changed into the peak wavelength of the desired light simply, without exchanging the whole light source. To do.

The light source for plant cultivation according to claim 1, which has been made to achieve the above object, is excited by light irradiation from a light emitting diode that emits light having a peak wavelength of 280 nm to 450 nm. a blue phosphor emitting blue light of 400 nm to 480 nm, the light emitting diode, or is excited by light irradiation from the other light emitting diodes emitting the same light and the light emitting diode, a red peak wavelength 610nm~780nm The blue light and the peak of the red light are formed by forming a translucent substrate material containing only a red phosphor emitting light and being dispersed and contained as a phosphor in a cap shape or a sheet shape. A firefly that can change the wavelength and the intensity ratio of the blue light and the peak wavelength of the red light according to the growth stage of the plant and the kind of the plant. Comprising a member, the fluorescent member, a light emitting diode removably attached have that plant cultivating light source, the blue _{phosphor, (SrCaBa) 5 (PO 4} ) 3 Cl: Eu, BaMgAl 10 It contains O ₁₇ : Eu, ZnS: Ag, CaS: Eu, and / or Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, and the red phosphor contains 3.5 MgO · 0.5MgF ₂ · GeO _2. : Mn, La ₂ O ₂ S: Eu, Y ₂ O ₂ S: Eu, LiEuW ₂ O ₈ , (Y, Gd, Eu) ₂ O ₃ , (Y, Gd, Eu) BO ₃ , and / or YVO ₄ : A light source for plant cultivation characterized by containing Eu and having an intensity ratio of blue light: red light = 1: 1 to 1:10 .

The light source for plant cultivation according to claim 2 is the light source for plant cultivation according to claim 1, wherein the cap-shaped fluorescent member is detachably attached to a portion made of a transparent resin enclosing a light emitting chip of the light emitting diode. It is mounted .

The light source for plant cultivation according to claim 3 is the light source for plant cultivation according to claim 1, wherein the blue light fluorescent member is one or more of the blue phosphors, and the red light fluorescent member is The red phosphor is formed by containing one or more kinds of red phosphors.

A light source for plant cultivation according to a fourth aspect is the light source for plant cultivation according to the first aspect, wherein a light scattering material is added to the fluorescent member .

A light source for plant cultivation according to a fifth aspect is the light source for plant cultivation according to the first aspect, wherein the translucent base material is silicone.

The light source for plant cultivation according to claim 6 is the light source for plant cultivation according to claim 5 , wherein the silicone is dimethyl silicone.

A light source for plant cultivation according to a seventh aspect is the light source according to the first aspect, wherein the light-emitting diode is a light-emitting diode that emits light having a wavelength of 350 nm to 420 nm.

The light source for plant cultivation according to claim 8 is the light source for plant cultivation according to claim 1, wherein a light guide member that guides light of the light emitting diode to the blue light fluorescent member and the red light fluorescent member is arranged. It is characterized by that.

  According to the light source for plant cultivation according to the present invention, a light transmitting material containing a blue phosphor that emits blue light having a peak wavelength of 400 nm to 480 nm when excited by light irradiation from a light emitting diode that emits light having a peak wavelength of 280 nm to 450 nm. Red light having a peak wavelength of 610 nm to 780 nm excited by light irradiation from a blue light fluorescent member formed of a conductive base material and the light emitting diode or another light emitting diode that emits light similar to the light emitting diode. By using a red light fluorescent member formed of a light-transmitting base material containing a red phosphor that emits light, the two blue and red colors necessary for plant growth can be obtained using one or the same type of light emitting diode. Various types of light can be emitted. Both wavelengths of the blue light and red light and the emission intensity ratio can be arbitrarily changed by appropriately adjusting the type and content of the phosphor. Furthermore, since the blue light fluorescent member and the red light fluorescent member are detachably attached, only these fluorescent members can be exchanged, and can be easily changed to the optimum light according to the plant growth stage and type. Therefore, plants can be cultivated stably and efficiently at low cost. Moreover, if the manufacturer of the light source for plant cultivation manufactures a plurality of types of fluorescent members, other configurations can be made common, so that the product storage location and its management are simple. In addition, since the fluorescent member can be more easily manufactured than the light emitting diode, a plant cultivation light source having a different wavelength or intensity ratio can be easily manufactured.

  Further, by changing the ratio of the number of the blue light fluorescent member and the red light fluorescent member, the emission intensity ratio between the blue light and the red light can be easily changed.

  According to the light source for plant cultivation according to the present invention, the blue light fluorescent material and the red light fluorescent material are contained in the same translucent base material, so that the blue light fluorescent material and the red light fluorescent material are formed by a common member. By being comprised, two types of light of blue and red required for the growth of a plant can be light-emitted from one light emitting diode. Therefore, the lighting circuit can be simplified.

  Moreover, according to the light source for plant cultivation according to the present invention, the intensity ratio of the emission peak wavelength of blue light and red light is blue light: red light = 1: 1 to 1:10, so that it is suitable for plant cultivation. Strength ratio.

  Moreover, according to the light source for plant cultivation according to the present invention, the blue light fluorescent member contains one or more blue phosphors, and the red light fluorescent member contains one or more red phosphors. As a result, blue light and red light can be converted into single-color light or a composite light of a plurality of single-color lights, and the light necessary for growing plants can be reduced by narrowing the band of each light. Can be made more suitable.

Moreover, according to the light source for plant cultivation according to the present invention, the blue phosphor is (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu, BaMgAl ₁₀ O ₁₇ : Eu, ZnS: Ag, CaS: Eu, and / or Sr. By containing ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, blue light can be efficiently emitted with the light of the light emitting diode.

Further, according to the light source for plant cultivation according to the present invention, the red _{phosphor, 3.5MgO · 0.5MgF 2 · GeO 2} : Mn, La 2 O 2 S: Eu, Y 2 O 2 S: Eu, LiEuW 2 By including O ₈ , (Y, Gd, Eu) ₂ O ₃ , (Y, Gd, Eu) BO ₃ , and / or YVO ₄ : Eu, red light is efficiently emitted with the light of the light emitting diode. be able to.

  Moreover, according to the light source for plant cultivation according to the present invention, the blue light fluorescent member and the red light fluorescent member are formed into a cap shape or a sheet shape, so that the cap-shaped fluorescent member is covered with a light emitting diode or a sheet. The shape of the light source for plant cultivation can be formed in an arbitrary shape by arranging the shape fluorescent member in the irradiation direction of the light emitting diode.

  Further, according to the light source for plant cultivation according to the present invention, since the translucent base material is silicone, it has a stable property due to the light emitted from the light emitting diode, so that discoloration and deterioration can be prevented. .

  Moreover, according to the light source for plant cultivation by this invention, discoloration and deterioration can further be prevented because silicone is dimethyl silicone.

  Moreover, according to the light source for plant cultivation by this invention, since a light emitting diode is a light emitting diode which light-emits light with a wavelength of 350 nm-420 nm, while being cheap, a fluorescent substance can be light-emitted efficiently.

  Furthermore, according to the light source for plant cultivation according to the present invention, the light guide member that guides the light of the light emitting diode to the fluorescent member is arranged, so that the light emitting diode and the fluorescent member can be arranged at arbitrary positions. For example, the plant cultivation light source can be made thin.

It is a perspective view explaining the structure of an example of the light source for plant cultivation to which this invention is applied. It is sectional drawing of said light source for plant cultivation. It is a partially expanded sectional view explaining the fixing method of the light emitting diode and fluorescent member of said light source for plant cultivation. It is a perspective view explaining the structure of another example of the light source for plant cultivation to which this invention is applied. It is a block diagram which shows the use condition of another example of the light source for plant cultivation to which this invention is applied. It is a block diagram which shows another example of the light source for plant cultivation to which this invention is applied. It is a perspective view which shows another example of the light source for plant cultivation to which this invention is applied. It is a graph which shows the emission spectrum of the light source for plant cultivation used in Examples 1, 2 and Comparative Example 1. It is the graph which showed the relationship between the length of a stem and elapsed days when cultivated mizuna with the light source for plant cultivation of Examples 1, 2 and Comparative Example 1. It is the graph which showed the relationship between the length of a stem, and elapsed days when it is said with the light source for plant cultivation of Example 2 and the comparative example 1, and cultivates a radish. 6 is a graph showing an emission spectrum of a plant cultivation light source used in Example 3.

  Although the preferable form for implementing this invention is demonstrated in detail below, the scope of the present invention is not limited to these forms.

  One aspect of the light source for plant cultivation of the present invention will be described with reference to the drawings. As shown in FIG. 1, in the plant cultivation light source 1, a fluorescent member 3 is put on a light emitting portion of a light emitting diode 2.

  For example, the light emitting diode 2 is formed into a bullet shape by enclosing a light emitting chip portion 4 that emits light and lead frames 5 and 5 for wiring to the light emitting chip portion 4 with a colorless and transparent epoxy resin. Yes. The rear end portion (lower end portion in the figure) of the bullet type is formed in a bowl shape having a larger diameter than the cannonball-like portion. The two terminals integrated with the lead frames 5 and 5 projecting downward from the hook-shaped portion are an anode electrode and a cathode electrode for energizing the light emitting chip portion 4.

  The light emitting diode 2 emits light within a wavelength range of 280 nm to 450 nm. In particular, it is preferable to emit light within a wavelength range of 350 nm to 420 nm. As the light-emitting diode that can be used in the present invention, a known light-emitting diode that emits light in the above-described wavelength region can be used. For example, an aluminum gallium nitride light-emitting diode, a diamond light-emitting diode, a zinc oxide light-emitting diode, or gallium nitride. Mention may be made of system light emitting diodes.

  The fluorescent member 3 is an example in which the blue light fluorescent member and the red light fluorescent member in the present invention are constituted by a common member, and the shell of the light emitting diode 2 is formed by a translucent base material as shown in FIG. It is molded into a cap shape that just covers the mold part and is detachably attached to the light emitting part of the light emitting diode 2. As this translucent base material, the light emitted from the light emitting diode 2 is stable with little discoloration and deterioration, and the light emitted from the blue phosphor and the red phosphor of the fluorescent member 3 is emitted. A transparent material can be used. For example, silicone, glass, epoxy resin, or acrylic resin can be exemplified. Particularly, the silicone has high stability to the light of the light emitting diode 2, hardly absorbs this light, and can be easily molded. Is preferred. Furthermore, it is more preferable that it is dimethyl silicone which has higher stability among silicones.

  The fluorescent member 3 is excited by light irradiation from the light emitting diode 2 and emits blue light in a region having a peak wavelength of 400 nm to 480 nm, and red that emits red light in a region having a peak wavelength of 610 nm to 780 nm. The phosphor is mixed and formed in the same translucent base material. The blue light and red light described above are light that includes the wavelengths of light necessary for growth according to the types of various plants and the growth stages of those plants. In particular, the blue phosphor more preferably emits blue light within the peak wavelength range of 430 nm to 460 nm, and the red phosphor more preferably emits red light within the peak wavelength range of 650 nm to 680 nm. This is due to the light wavelength required for many plants.

  For example, a light scattering material such as titanium oxide and calcium carbonate can be added to the fluorescent member 3.

  A cross-sectional view of the state in which the fluorescent member 3 is put on the light emitting portion of the light emitting diode 2 is shown in FIG. In the case where the fluorescent member 3 is formed by selecting silicone as the translucent base material and having elasticity, as shown in FIG. Can be detachably fixed. 3A, the end of the fluorescent member 3 can be bonded and fixed to the flange of the light emitting diode 2 with the adhesive 8 as shown in the partially enlarged sectional view near the flange. In this case, the adhesive 8 is peeled off when the fluorescent member 3 is removed, and the adhesion is performed again when the fluorescent member 3 is attached. Further, as shown in FIG. 3B, the light emitting diode 2 may be provided with a convex portion 9a, and the fluorescent member 3 may be provided with a concave portion so as to be fitted thereto so that the light emitting diode 2 can be detachably fixed. Further, as shown in FIG. 3C, the light emitting diode 2 may be provided with a male screw 9b, and the fluorescent member 3 may be provided with a female screw, or as shown in FIG. 3D, the light emitting diode 2 is provided. A fitting hole 9c may be provided on the fluorescent member 3, and a fixing claw may be provided on the fluorescent member 3. In addition, the fluorescent member 3 can be detachably fixed to the light emitting diode 2 by using a known fixing method.

  The light-transmitting base material of the fluorescent member 3 desirably contains the blue phosphor and the red phosphor that emit light in the blue and red wavelength regions. For example, when silicone is used for the translucent substrate, the silicone material and both phosphors are mixed well, poured into a mold having a desired shape, and heated and pressed, so that both phosphors are evenly distributed in the silicone. The fluorescent member 3 dispersed in the above can be obtained.

  When the blue phosphor and the red phosphor emit light by light irradiation from the light emitting diode 2, the intensity ratio of each emission peak wavelength (spectrum peak wavelength) of the blue light and the red light in the wavelength region is blue light. : Red light = 1: 1 to 1:10, more preferably blue light: red light = 1: 5 to 1:10. Moreover, the kind of blue fluorescent substance contained in the translucent base material is not limited to one kind, and two or more kinds may be mixed. Similarly, the kind of red fluorescent substance is not limited to one kind, and two or more kinds are included. You may mix.

As the blue phosphor, any material can be used as long as it can emit blue light in the wavelength region by light irradiation from the light emitting diode 2, and preferably (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu, BaMgAl ₁₀ O ₁₇ : Eu, ZnS: Ag, CaS: Eu, Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu can be mentioned. The blue phosphor is preferably a pigment system. Further, it is more preferable to combine blue phosphors having different emission peak wavelengths, since the half width of the emission peak wavelength can be widened.

As the red phosphor, any phosphor can be used as long as it can emit blue light in the wavelength region by light irradiation from the light-emitting diode 2, and preferably 3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn _{, La 2 O 2 S: Eu} , Y 2 O 2 S: Eu, LiEuW 2 O 8, (Y, Gd, Eu) 2 O 3, (Y, Gd, Eu) BO 3, YVO 4: the like Eu Can do. The red phosphor is preferably a pigment system. It is more preferable to combine red phosphors having different emission peak wavelengths because the half width of the emission peak wavelength can be widened.

  The operation of the plant cultivation light source 1 will be described with reference to FIG.

  The light emitting chip portion 4 emits light by energizing from a lighting circuit (not shown) between the anode electrode and the cathode electrode of the light emitting diode 2. This light is emitted from the light emitting diode 2 to the fluorescent member 3. By this light irradiation, the blue phosphor and the red phosphor of the fluorescent member 3 are excited to emit blue light and red light. For this reason, from the fluorescent member 3, as shown by the arrow in FIG. 2, light for plant cultivation L in which blue light and red light are mixed is irradiated. Note that most of the light emitted by the light emitting diode 2 is absorbed by the blue phosphor and the red phosphor.

  A plant may be cultivated using one light source 1 for plant cultivation, or a plant may be cultivated using a plurality according to the desired amount of light.

  When changing the light emission peak wavelength of each of the blue light and red light of the plant cultivation light source 1 and their light emission intensity ratio, the fluorescent member 3 is replaced. That is, it is performed by appropriately selecting the types of the blue phosphor and the red phosphor, adjusting the contents thereof, and exchanging with the fluorescent member 3 manufactured in advance so as to obtain a desired emission peak wavelength and emission intensity ratio.

  The present invention can also be applied to the surface-mounted light emitting diode 2. FIG. 4 shows a plant cultivation light source 1 a configured by covering a surface-mounted light emitting diode 2 with a cap-shaped fluorescent member 3. In addition, about the thing similar to the structure already demonstrated, the same code | symbol is attached | subjected and description is abbreviate | omitted. In the figure, a light emitting diode 2 having a substantially rectangular parallelepiped chip shape is attached to a substrate 31 on which printed patterns 32a and 32b for circuit connection are formed. The anode electrode 30a and the cathode electrode 30b of the light emitting diode 2 are soldered to the soldering lands of the print patterns 32a and 32b. The fluorescent member 3 is formed in a cap shape having a recess that fits over the light emitting diode 2. In this example, after the light emitting diode 2 is soldered to the substrate 31, the fluorescent member 3 is attached to the light emitting diode 2. In addition, as long as the fluorescent member 3 has heat resistance with respect to the heat at the time of soldering, soldering may be performed in a state where the fluorescent member 3 is covered on the light emitting diode 2 in advance. Thus, even the surface-mounted light emitting diode 2 can be used as the plant cultivation light source of the present invention by covering with the fluorescent member 3.

  Next, another aspect to which the present invention is applied will be described with reference to FIG.

  In the plant cultivation light source 1b, a substrate 10 on which a plurality of light emitting diodes 2 are mounted is disposed in a box 14 having an opening on one side, and a rectangular shape is formed so as to cover and cover the opening of the box 14. A fluorescent member 3a formed into a sheet shape is mounted and configured. Each of the light emitting diodes 2 is mounted on the substrate 10 in a direction in which light is emitted toward the opening of the box body 14. The plurality of light emitting diodes 2 are mounted on the substrate 10 in various plane shapes such as a rectangle and a circle, for example, arranged in a line, arranged vertically and horizontally in a matrix, or concentrically.

  The fluorescent member 3a is different in shape only from the cap-shaped fluorescent member 3 already described, and like the fluorescent member 3, a blue fluorescent material and a red fluorescent material are contained in a translucent base material to form a sheet shape. It is formed. Further, similarly to the fluorescent member 3, the fluorescent member 3a corresponds to an example in which the blue light fluorescent member and the red light fluorescent member of the present invention are configured by a common member.

  The fluorescent member 3 a is detachably attached to the opening of the box body 14 by a fixing member 15. The fixing member 15 is fixed to the edge of the opening of the box body 14 by, for example, a screw (not shown). By removing this screw, the fixing member 15 is removed and the fluorescent member 3a is attached and detached. In order to protect and maintain the shape of the fluorescent member 3a, the fluorescent member 3a is made of a transparent member such as a glass plate having substantially the same size as the fluorescent member 3a, or a transparent member or a translucent member containing a light scattering material. It may be supported and fixed to the box 14. Further, the four sides of the fluorescent member 3a may be covered and protected by a frame material.

  In the plant cultivation light source 1b, the fluorescent member 3a is irradiated with light from the plurality of light emitting diodes 2, and the blue phosphor and the red phosphor of the phosphor member 3a are excited, and as shown in FIG. L is irradiated. Plant P is grown by this plant cultivation light L.

  Next, still another embodiment to which the present invention is applied will be described with reference to FIG.

  The light source 1c for plant cultivation is provided with a light guide member 6 that guides light from the light emitting diode 2 to the fluorescent member 3a. As schematically shown in the figure, in the plant cultivation light source 1 b, the light emitting diode 2 is emitted on the inner side surface of the thin box 14 whose one surface is open, and the light is emitted on the center side of the box 14. It is arranged in the direction. A plate-like light guide member 6 having the same size as that of the fluorescent member 3 a is disposed in the box 14, and the fluorescent member 3 a is a fixing member 15 so as to cover the opening of the box 14. It is detachably attached.

  As an example, the light guide member 6 is a light guide plate in which a light emitting side surface of an acrylic plate is V-grooved with a laser or the like, and light incident from an end face is uniformly surface-emitted. The light emitted from the light emitting diode 2 is irradiated from the light guide member 6 to the fluorescent member 3a. Thereby, as shown in the figure, the plant cultivation light L is irradiated from the fluorescent member 3a to the outside. In addition, a film-like light scattering member can also be disposed between the light guide member 6 and the fluorescent member 3a as an example for scattering and transmitting light. Further, a film-like light reflecting member can be disposed on the opposite surface side of the light guide member 6 to the fluorescent member 3a as an example of reflecting light toward the fluorescent member 3a. In addition, a light reflecting plate that directs the emitted light toward the light guide member 6 can be disposed around the light emitting diode 2.

  In this case, the plurality of light emitting diodes 2 are preferably arranged in a line along the side surface of the light guide member 6 so as to be arranged from the front surface side to the back surface side of the illustrated paper surface. Further, the light emitting diode 2 can be disposed not only on one side surface of the box body 14 but also on the side surface facing the one side surface or on the entire periphery.

  The plant cultivation light source 1c can be thinner than the plant cultivation light source 1b.

  Next, still another aspect to which the present invention is applied will be described with reference to FIG.

  A light source 1d for plant cultivation shown in FIG. 7 includes a blue light source 22 (three shown as an example) and a red light source 24 (shown as six as an example) mounted on a substrate 28. A light scattering plate 29 is provided in the light emission direction (upward in the figure).

  The blue light source 22 and the red light source 24 are arranged so as to be appropriately dispersed on the substrate 28. In the figure, the blue light source 22 is arranged in the middle one of the three rows and the red light source 24 is arranged in the two rows on both sides. However, the present invention is not limited to this, and the number of blue light sources 22 and red light sources 24 is not limited to this. It arranges so that it may be mixed appropriately according to.

  The blue light source 22 is configured by detachably covering the light emitting diode 2 described above with the blue light fluorescent member 21. Similarly to the fluorescent member 3 already described, the blue light fluorescent member 21 is formed in a cap shape by containing a blue phosphor in a translucent base material.

  The red light source 24 is configured by covering a similar light emitting diode 2 with a red light fluorescent member 23 in a detachable manner. The red light fluorescent member 23 is formed in a cap shape by containing a red fluorescent material in a translucent base material in the same manner as the fluorescent member 3 already described.

  The light scattering plate 29 is a thin plate formed by adding a light scattering material that scatters light to a transparent material. In the figure, the side walls that connect the side surfaces of the substrate 28 and the light scattering plate 29 and prevent light leakage in the side surface direction are not shown. The light scattering plate 29 is detachably attached to the plant cultivation light source 1d like the fluorescent member 3 detachably attached to the plant cultivation light sources 1b and 1c.

  This plant cultivation light source 1d operates as follows.

  When the light emitting diodes 2 of the blue light source 22 and the red light source 24 are energized from a lighting circuit (not shown), the light emitting diode 2 emits light. Thereby, the blue phosphor of the blue light fluorescent member 21 is excited, the blue light source 22 emits blue light having a peak wavelength of 400 nm to 480 nm, and the red light source 24 is excited of the red phosphor of the red light fluorescent member 23. And emits red light having a peak wavelength of 610 nm to 780 nm. The blue light and the red light are scattered by the light scattering plate 29, and the plant cultivation light L mixed with the blue light and the red light is irradiated.

  The emission intensity ratio of the blue light and the red light of the plant cultivation light source 1d can be changed by appropriately changing the ratio of the numbers of the blue light sources 22 and the red light sources 24. That is, the light emission intensity ratio can be changed by appropriately changing the ratio of the number of the blue light fluorescent member 21 and the red light fluorescent member 23 that covers the light emitting diode 2 mounted on the substrate 28. Since the blue light fluorescent member 21 and the red light fluorescent member 23 are detachably mounted on the light emitting diode 2, the light emission intensity ratio can be easily changed. Further, since only the same type of light emitting diode 2 is mounted on the substrate, the lighting circuit can be made simpler than when different types of light emitting diodes are mounted.

  When light is emitted from the light emitting diode 2 to a desired range, the light scattering plate 29 may not be provided. Further, instead of the light scattering plate 29, a light scattering material can be added to the blue light fluorescent member 21 and the red light fluorescent member 23.

  As described above, the plant cultivation light sources 1, 1a, 1b, 1c, and 1d are compact in shape and do not generate heat as compared with high-intensity discharge lamps and fluorescent lamps. be able to. Therefore, space use efficiency can be improved by arranging many shelves each arranged with the light source for plant cultivation of the present invention up and down to grow plants.

  In the plant cultivation light sources 1, 1 b, 1 c, and 1 d, the example in which the light-emitting diode 2 has a bullet-shaped shape has been described. However, the shape of the light-emitting diode that can be used in the present invention is not particularly limited, and is hemispherical. It may be a rectangular parallelepiped type or a cylindrical type. Further, the light emitting diodes 2 of the plant cultivation light sources 1b, 1c, and 1d can be changed to the surface mount type as shown in the plant cultivation light source 1a. Further, a light emitting diode 2 provided with a lens for condensing or diffusing light may be used. Further, a lens for condensing or diffusing light on the fluorescent member 3, the blue light fluorescent member 21, and the red light fluorescent member 23 can be integrally formed at the same time as adhesion or fluorescent member forming.

  Further, the fluorescent members 3 and 3a may be formed as a laminated structure. For example, a first layer in which a blue phosphor is mixed with a light-transmitting base material and a second layer in which a red phosphor is mixed with a light-transmitting base material can be stacked. Specifically, in the case of the cap-shaped fluorescent member 3, a first layer in which a cap-shaped blue phosphor covering the light-emitting diode 2 is mixed with a translucent base material, and a cap shape covering the first layer. It is also possible to form a laminate of a second layer obtained by mixing the red phosphor with a translucent base material. The order of the layers may be reversed. At this time, the first layer and the second layer can be fixed with an adhesive or the like, or both layers may be stacked in a detachable manner. In the case of the sheet-shaped fluorescent member 3a, the first layer in which the sheet-shaped blue phosphor is mixed with the translucent base material and the second layer in which the sheet-shaped red phosphor is mixed with the translucent base material. Laminate layers. In addition, a layer formed of silicone or the like to which a scattering agent is added can be further stacked on both the stacked layers.

  Alternatively, a translucent base material mixed with a phosphor can be applied to the surface of silicone or the like to form a laminated structure. In this case, the translucent substrate material is preferably one that has fluidity at the time of application and can be stably fixed after application, and examples thereof include silicone for coating and curable silicone. The layer formed by coating may be applied by mixing both blue phosphor and red phosphor, or after applying a transparent base material mixed with blue phosphor and mixing red phosphor. It is good also as a laminated structure by apply | coating the translucent base material which carried out.

  Examples of light sources for plant cultivation to which the present invention is applied are shown in Examples 1, 2 and 3, and examples of light sources for plant cultivation to which the present invention is not applied are shown in Comparative Examples 1 and 2.

Example 1
In Example 1, six plant cultivation light sources 1 of the form shown in FIGS. 1 and 2 are manufactured, arranged in a row on a substrate, connected to each other with a current limiting resistor, and connected in parallel to produce six lamps. It was set as the light source for plant cultivation which has. As the light-emitting diode 2, a bullet-type near-ultraviolet light-emitting diode (manufactured by Abrite, AL-513UVC-A, emission peak wavelength 403 nm) was used. The cap-shaped fluorescent member 3 is mixed with blue phosphor and red phosphor at a compounding ratio (mass ratio) shown in Table 1 with respect to 1.3 g of dimethyl silicone per cap, and poured into a mold for heating. Using a press, vulcanization was performed at 11 MPa and 130 ° C. for 5 minutes to form. The blue phosphor used (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu, and the red phosphor used 3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn. The light source for plant cultivation was supplied with power from a direct current stabilized power source to emit light. The light emission current (whole 6 lighting) and the intensity ratio of the emission peak wavelength of the blue light in the wavelength range of 400 nm to 480 nm and the red light in the wavelength range of 610 nm to 780 nm are shown in the same table. A graph is shown in FIG.

(Example 2)
Example 2 was prepared by changing only the blending ratio of the blue phosphor and the red phosphor to the blending ratio shown in Table 1 from the light source for plant cultivation of Example 1. The intensity ratio of the emission peak wavelengths of blue and red is shown in the same table, and the emission spectrum is shown in FIG.

Example 3
In Example 3, the emission spectrum of the plant cultivation light L was measured by changing the ratio of the numbers of the blue light source 22 and the red light source 24 in the same manner as the plant cultivation light source 1d shown in FIG. . A plurality of light emitting diodes 2 similar to the near ultraviolet light emitting diodes used in Example 1 were arranged on the substrate 28. The light-emitting diode 2 was mounted so that the blue light fluorescent member 21 and the red light fluorescent member 23 were appropriately dispersed. The blue light fluorescent member 21 is mixed with 1.3 g of dimethyl silicone per 0.3 g of blue phosphor, poured into a mold, and vulcanized at 11 MPa, 130 ° C. for 5 minutes using a heating press. Go and molded. As the blue phosphor, (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu was used. The red light fluorescent member 23 was formed under the same conditions as the blue light fluorescent member 21 by mixing 0.3 g of red phosphor with 1.3 g of dimethyl silicone per piece, pouring it into a mold. As the red phosphor, 3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn was used. The light scattering plate 29 was a silicone plate having a thickness of 0.7 mm. To this light scattering plate 29, titanium oxide and calcium carbonate were added as light scattering materials.

  Light source for plant cultivation when the ratio of the number of blue light fluorescent member 21 (blue light source) and red light fluorescent member 23 (red light source) is changed to 1: 1, 1: 2, 1: 3, 1: 4 An emission spectrum graph of 1d is shown in FIG. Depending on the ratio, there is a light emitting diode 2 in which neither the blue light fluorescent member 21 nor the red light fluorescent member 23 is mounted. Such a light emitting diode 2 is turned off.

  From the result of FIG. 11, the intensity ratio of the emission peak wavelength in blue (wavelength 400 nm to 480 nm) and red (610 nm to 780 nm) increased as the ratio of the red light fluorescent member 23 increased. In the figure, since the spectral intensity is shown in relative intensity (arbitrary scale), the blue peak intensity decreases as the ratio of the red light fluorescent member 23 increases.

  As described above, it was confirmed that the ratio of the blue light to the red light was changed by changing the ratio of the blue light fluorescent member 21 and the red light fluorescent member 23. Thus, by using the substrate 28 on which the light emitting diodes 2 having the same light emission peak wavelength are arranged, the number of the blue light fluorescent members 21 and the red light fluorescent members 23 is appropriately changed at a desired ratio, thereby obtaining a light intensity ratio. It was confirmed that can be changed easily. Therefore, light suitable for plant growth can be easily obtained.

(Comparative Example 1)
Six bullet-type white light emitting diodes (NSPA 510BS, manufactured by Nichia Corporation) are arranged in a line on the substrate, and each is connected to a current limiting resistor and connected in parallel to form a light source having six lights. . The current during light emission (6 whole lighting) and the intensity ratio of emission peak wavelengths of blue and red are shown in the same table, and the emission spectrum is shown in FIG.

(Cultivation container used for cultivation experiment)
The top of a cylindrical container having a height of 23 cm and a diameter of 22 cm was covered, and a container that did not allow light to enter from the outside was used. The container used was glossy with a metal-plated surface so that light was reflected. The light sources of Examples 1 and 2 and Comparative Example 1 were each attached to the inner central part of the lid of a separate container so that the position was 20 cm from the front end of the light source to the bottom surface of the container.

(Mizuna cultivation experiment)
Sponge was spread on a glass plate, seeds of mizuna were placed on it, and three pieces of water were prepared so that the seeds were lightly soaked. The glass dishes were placed one by one in the center of the bottom of the container for cultivation to which the light sources of Examples 1 and 2 and Comparative Example 1 were attached. FIG. 9 shows the relationship between the stem length of the mizuna grown in this way and the number of days elapsed.

  The stems grew longer in Examples 1 and 2 than in Comparative Example 1. Moreover, the stem grew longer in Example 2 than in Example 1.

(Kaiware radish cultivation experiment)
Sponges were spread on a glass plate, and radish seeds were placed on top of them, and two were prepared so that the seeds were soaked lightly. The glass dishes were placed one by one in the center of the bottom of the container for cultivation to which the light source of Example 2 and Comparative Example 1 was attached, and were simultaneously cultivated with the light source turned on. FIG. 10 shows the relationship between the length of the radish stems and the number of days elapsed.

  The stem grew longer in Example 2 than in Comparative Example 1.

(Comparative Example 2)
As Comparative Example 2, a white light-emitting diode (NSSM016A, manufactured by Nichia Corporation) in which three light-emitting diodes of red, green, and blue were incorporated in one chip was used as a light source for plant cultivation. This white light emitting diode has a total of six terminals: an anode electrode and cathode electrode for red, an anode electrode and cathode electrode for green, an anode electrode and cathode electrode for blue, and each of red, green, and blue Since it is necessary to connect three lighting circuits for diodes, the lighting circuit becomes complicated. Further, in order to change the light emission intensity ratio of each light, the current supplied from the three lighting circuits must be varied, which further complicates the circuit.

  The light source for plant cultivation of the present invention is used as a light source for artificially cultivating plants such as vegetables, fruits and flower buds.

  1, 1a, 1b, 1c, 1d are light sources for plant cultivation, 2 is a light emitting diode, 3, 3a is a fluorescent member, 4 is a light emitting chip portion, 5 is a lead frame, 6 is a light guide member, 8 is an adhesive, 9a Is a projection, 9b is a male screw, 9c is a fitting hole, 10 is a substrate, 14 is a box, 15 is a fixing member, 21 is a blue light fluorescent member, 22 is a blue light source, 23 is a red light fluorescent member, and 24 is Red light source, 28 and 31 are substrates, 29 is a light scattering plate, 30a is an anode electrode, 30b is a cathode electrode, 32a and 32b are printed patterns, L is plant cultivation light, and P is a plant.

Claims (8)

Are excited by light irradiation from the light-emitting diode which emits light of peak wavelength 280Nm～450nm, a blue phosphor emitting blue light having a peak wavelength of 400 nm to 480 nm, the light emitting diode or similar light and the light emitting diode A translucent substrate material containing only a red phosphor that is excited by light irradiation from another light emitting diode that emits light and emits red light having a peak wavelength of 610 nm to 780 nm is dispersed and contained as the phosphor. By being formed into a cap shape or a sheet shape, the peak wavelength of the blue light and the red light and the intensity ratio of the peak wavelength of the blue light and the red light are set to the growth stage of the plant and the kind of the plant. With a fluorescent member that can be changed according to
The fluorescent member is a plant cultivating sources that have been detachably attached to the light emitting diode,
The blue phosphor includes (SrCaBa) ₅ (PO ₄ ) ₃ Cl: Eu, BaMgAl ₁₀ O ₁₇ : Eu, ZnS: Ag, CaS: Eu, and / or Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu. Is,
The red _{phosphor, 3.5MgO · 0.5MgF 2 · GeO 2} : Mn, La 2 O 2 S: Eu, Y 2 O 2 S: Eu, LiEuW 2 O 8, (Y, Gd, Eu) 2 O ₃ , (Y, Gd, Eu) BO ₃ , and / or YVO ₄ : Eu,
A light source for plant cultivation, wherein the intensity ratio is blue light: red light = 1: 1 to 1:10 . The light source for plant cultivation according to claim 1, wherein the cap-shaped fluorescent member is detachably attached to a portion made of a transparent resin enclosing a light emitting chip of the light emitting diode .   2. The plant according to claim 1, wherein the fluorescent member includes one or more of the blue phosphors and one or more of the red phosphors. Light source for cultivation. The light source for plant cultivation according to claim 1, wherein a light scattering material is added to the fluorescent member .   The light source for plant cultivation according to claim 1, wherein the translucent base material is silicone. The light source for plant cultivation according to claim 5 , wherein the silicone is dimethyl silicone.   The light source for plant cultivation according to claim 1, wherein the light emitting diode is a light emitting diode that emits light having a wavelength of 350 nm to 420 nm.   The light source for plant cultivation according to claim 1, further comprising a light guide member for guiding the light of the light emitting diode to the fluorescent member.

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