JP2008022812A - Lighting apparatus for plant growth - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting apparatus for plant growth, with which optical damage and burn on the phylloplane of plant are controlled and simultaneously plant growth is promoted and when plants are spread on a horizontal plane and a plurality of plants exist, their growths are approximately uniformly promoted. <P>SOLUTION: The lighting apparatus for plant growth has a light source 2 and an infrared restriction plate 4 and is arranged above plants P. The infrared restriction plate 4 is arranged between the light source 2 and the plants P and limits transmission of infrared emitted from the light source 2. The infrared restriction plate 4 is constituted to minimize infrared transmittance at a part to intersect a vertical line stood on an irradiation surface 4a from the light source 2 and to raise it with the separation from the part and an infrared exposure dose to the plants P is approximately uniformly adjusted regardless of a position on an approximately horizontal plane. According to the constitution, optical damage and burn on the phylloplane of plant of the plants P are controlled and simultaneously an infrared exposure dose to promote growth of the plants P is secured by the infrared restriction plate 4. When a plurality of the plants P exist on a horizontal plane, their growth is approximately uniformly promoted. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plant-growing lighting device that irradiates a plant with light in order to promote the growth of the plant.

Conventionally, as an illuminating device for plant growth that restricts the amount of infrared rays, that is, the amount of heat rays contained in irradiation light to plants, for example, heat rays contained in light rays emitted from a light source are removed with a cold mirror to emit only visible light. There is known a plant cultivation apparatus that sends light to a transmission system and emits light emitted from a luminescent material that is arranged close to the cultivated plant (see, for example, Patent Document 1). In this apparatus, the illuminant irradiates a plant with light rays from a short distance, repeats reflection and absorption of light rays between plants, and finally causes the plants to absorb and use them. According to this apparatus, since infrared rays are removed, it is possible to suppress light damage and burns on the foliage, and to prevent temperature rise in the building where the apparatus is installed.
Japanese Patent Application Laid-Open No. 07-107868

  By the way, in addition to blue light and red light, which are visible light, when a near-infrared ray having a wavelength of, for example, 730 nm is irradiated to a plant, the photosynthesis of the plant is promoted and the growth of the plant is promoted. Therefore, it is necessary to irradiate the plant with infrared rays in the plant growing lighting device. Further, when the temperature is low, in order to warm the plant to a temperature suitable for growth, it is required to irradiate the plant with infrared rays that are heat rays. However, in the technique described in Patent Document 1, since heat rays, that is, infrared rays are removed and the plant is not irradiated, it is possible to suppress light damage and burning of the foliage, but it has an Emerson effect and is suitable for plant growth. It was difficult to promote the growth of plants by maintaining a proper temperature.

  In addition, when a light source that emits infrared rays but does not control the amount thereof and emits light radially is used for illumination of the plant growing lighting device, the amount of infrared rays decreases in inverse proportion to the square of the distance. Therefore, a difference occurs in the amount of infrared rays that the plant receives depending on the distance between the light source and the plant. For this reason, when there are a plurality of plants and seedlings spread on the horizontal plane, the difference in the amount of infrared rays that they are exposed to depends on the position at which they are placed, so it was difficult to uniformly grow the plants and seedlings.

  The present invention has been made to solve the above-described conventional problems, and suppresses light damage and burning on the leaf surface of the plant, promotes the growth of the plant, and when a plurality of plants are spread on the horizontal plane. Another object of the present invention is to provide a plant-growing lighting device that can promote the growth thereof substantially uniformly.

  In order to achieve the above object, a first aspect of the present invention is a plant-growing lighting device for irradiating a plant with light in order to promote plant growth, and a light source that is arranged inside the rod and emits light. And a reflecting plate that reflects visible light and infrared light emitted from the light source, and is disposed between the light source and the plant, and transmits visible light emitted from the light source and visible light reflected by the reflecting plate. And limiting the amount of infrared light emitted from the light source and the amount of infrared light reflected by the reflecting plate, and an infrared limiting member having an irradiation surface for irradiating light to the plant, the infrared limiting member, An infrared transmittance per unit area of the member is configured to be lowest at a portion where the light beam intersects a perpendicular line standing on the irradiation surface from the light source, and the amount of infrared irradiation with respect to the plant is substantially related to the position on the horizontal plane. It is obtained as a Razz substantially uniform.

  According to a second aspect of the present invention, in the plant-growing lighting device according to the first aspect, the infrared limiting member has an infrared transmittance per unit area of the member that intersects with a vertical line standing on the irradiation surface from the light source. It is comprised so that it may become high as it leaves | separates from the site | part which turns.

  The invention of claim 3 is the plant growing lighting device according to claim 1 or 2, wherein the plant growing illumination device is disposed between the light source and the reflector, and transmits visible light emitted from the light source. An infrared reflecting member that reflects infrared light emitted from the light source is provided.

  According to the invention of claim 1 or claim 2, it is possible to prevent light damage and burning on the leaf surface of the plant, and at the same time, it is possible to secure an irradiation amount of infrared rays necessary for the growth of the plant. Moreover, since the irradiation amount of infrared rays with respect to the plant becomes substantially uniform regardless of the position on the horizontal plane, the growth of a plurality of plants spread on the horizontal plane can be promoted substantially uniformly.

  According to the third aspect of the present invention, the traveling direction of the infrared rays can be changed by the infrared reflecting member, and the infrared rays can be incident on the portion where the infrared transmittance of the infrared limiting member is high, so that the infrared rays can be emitted efficiently.

  Hereinafter, a plant-growing lighting device (hereinafter abbreviated as this device) according to an embodiment of the present invention will be described with reference to the drawings. 1 and 2 show a configuration and a usage state of a main part of the apparatus. This device is a device that irradiates light to the plant P in order to promote the growth of the plant P, and is disposed above the plant P. There are a plurality of plants P to which light is irradiated, for example, one plant is planted in a pot and scattered on a horizontal plane. Moreover, the plant P which exists in multiple strains may not be planted in the pot, but may be spread on a horizontal surface and planted in soil. Furthermore, the plant P may exist not only in a plurality of strains but only in one strain, and may spread and extend on a horizontal plane.

  The apparatus includes a housing 1, a light source 2 that is disposed inside the housing 1 and has a light emitting unit 21 that emits light, a reflector 3 that reflects visible light and infrared light emitted from the light source 2, and a light source 2. And an infrared limiting plate 4 disposed between the plant P and an infrared reflecting plate 5 disposed between the light source 2 and the reflecting plate 3. The reflecting plate 3 has a semi-cylindrical shape, for example, and is provided so as to cover the light source 2 from above, and the light source 2 is disposed inside the reflecting plate 3. The reflection plate 3 arranged in this manner reflects light emitted from the light source 2 and traveling in a direction different from the direction in which the plant P is present, and is reflected by the inner surface 3a, and the traveling direction of the light is the direction in which the plant P exists. Change to The infrared limiting plate 4 transmits visible light emitted from the light source 2 and visible light reflected by the reflecting plate 3, and limits the amount of infrared light emitted from the light source 2 and reflected by the reflecting plate 3. (Infrared limiting member). Further, the infrared reflecting plate 5 transmits visible light emitted from the light source 2 and reflects infrared light emitted from the light source 2 (infrared reflecting member). Below, the component of this apparatus is demonstrated in detail. In the present embodiment, the wavelength of visible light is, for example, 400 to 720 nm, and the wavelength of infrared light is, for example, 720 nm to 1 mm.

  The housing 1 has an opening 1 a on the bottom surface, and the opening area of the opening 1 a is substantially the same as the planar view area of the reflector 3. The housing 1 covers a semi-cylindrical reflecting plate 3 and includes the reflecting plate 3 inside according to the opening 1a. The housing 1 further includes a support portion (not shown) that supports the reflection plate 3 so as to increase the strength of the reflection plate 3 disposed therein and to absorb the impact on the reflection plate 3. 3 has an outer structure in which a gap is provided. With this outer structure, it is possible to make it difficult for the impact on the housing 1 to be transmitted to the reflecting plate 3, and as the temperature of the housing 1 rises as the temperature of the reflecting plate 3 rises due to radiant heat from the light source 2, It is possible to prevent burns when the housing 1 is touched. The material of the housing 1 is not easily rusted even in a humid agricultural greenhouse or glass house and needs to have sufficient strength to hold the light source 2, the reflector 3, etc. Iron or the like that has been painted to prevent corrosion is desirable.

  The light source 2 includes a light emitting unit 21 that emits light, and includes, for example, a high-intensity discharge lamp or an incandescent lamp. When the light source 2 is a high-intensity discharge lamp, the light emission part 21 consists of an arc tube, and when the light source 2 is a high-intensity discharge lamp, the light emission part 21 consists of a filament. The light source 2 is provided, for example, horizontally, and emits light including blue light, red light, and infrared light. This infrared ray includes a near infrared ray and a far infrared ray. The light source 2 may be a fluorescent lamp. The surface temperature of a fluorescent lamp may exceed 45 ° C., and emits an infrared ray having a light amount necessary for plant growth.

  The reflection plate 3 has a semi-cylindrical shape as described above, and is shaped so that the amount of reflected light is substantially uniform on the upper surface of the infrared limiting plate 4. The reflection plate 3 having such a shape reflects the visible light and infrared rays emitted from the light source 2 disposed inward with high efficiency, and is provided in parallel with the lateral light source 2. In addition, the shape of the reflecting plate 3 is not limited to a semi-cylinder, and may be, for example, a semi-elliptical cylinder or a shape in which the outer shape of the cross section is a perfect circle or an elliptical arc. Furthermore, when the light source 2 is provided vertically, the shape of the reflecting plate 3 may be a bowl shape whose diameter is expanded downward.

  Further, the reflecting plate 3 is made of aluminum whose reflectance is increased by, for example, anodizing, vapor deposition plating, polishing or the like in order to reduce the weight and ensure high reflectance. The reflecting plate 3 is made of, for example, iron that has been subjected to vapor deposition of silver or aluminum, iron that has been coated to increase reflectivity, and a film that has been subjected to vapor deposition of silver or aluminum. You may be comprised with the metal, glass, resin, etc. to which the reflective sheet was affixed. Further, the reflecting plate 3 may be made of, for example, stainless steel in order to provide corrosion resistance or to have high strength.

  The infrared restriction plate 4 is a plate having a square or rectangular shape in plan view, and is made of a member that transmits visible light with high efficiency and restricts the amount of infrared transmission. This member has, for example, a transparent resin or a base material made of transparent glass having heat resistance that can withstand high heat, and the surface of the base material has an infrared reflecting material or an infrared ray to limit the amount of infrared light transmitted. An absorbing material is applied or deposited to form an infrared reflecting film or an infrared absorbing film. The infrared transmission amount is limited by adjusting the infrared transmittance of the infrared limiting plate 4. The infrared transmittance is adjusted based on the thickness or material of the infrared reflecting film or infrared absorbing film. In this adjustment, the infrared transmittance is set to substantially zero, and almost all infrared rays are not removed.

  The area of the infrared limiting plate 4 is substantially the same as the planar view area of the reflecting plate 3 or the area of the opening 1 a of the housing 1. In addition, the infrared limiting plate 4 is bonded and fixed to the end 3 b on the side of the central axis of the reflecting plate 3, or is arranged so as to close the opening 1 a of the housing 1. Therefore, the light source 2 is located in a space surrounded by the reflector 3 and the infrared restriction plate 4, and the infrared restriction plate 4 is located between the light source 2 and the plant P disposed below the apparatus. Will do. Due to this positional relationship, the infrared limiting plate 4 transmits the visible light emitted from the light source 2 and the visible light reflected by the reflecting plate 3, and the infrared light emitted from the light source 2 and the infrared light reflected by the reflecting plate 3. Limit the amount of transmission. Visible light and infrared light (shown by solid lines) that have passed through the infrared restriction plate 4 are emitted from the irradiation surface 4a, which is the lower surface of the infrared restriction plate 4, and irradiated to the plant P below.

  As described above, since the amount of infrared transmission is limited in the infrared limiting plate 4, the amount of infrared irradiation on the plant P can be limited. Therefore, it is possible to suppress light damage and burning on the leaves of the plant P. At the same time, the infrared rays irradiated to the plant P are not completely removed by the infrared restricting plate 4 but only the amount of transmission is limited by adjusting the infrared transmittance, so that it is necessary for the growth of the plant P. A sufficient amount of infrared irradiation. For example, since infrared rays are heat rays, thermal radiation is performed on the plant P when the infrared rays are emitted on the plant P. For this reason, even in cold seasons such as autumn and winter, the temperature of the plant P can be made suitable for growth, and the growth of the plant P can be promoted. Further, the infrared limiting plate 4 transmits visible light and limited amount of infrared light, and since this infrared light includes near infrared light, in addition to blue light and red light that are visible light, the near infrared light is transmitted. Is irradiated to the plant P. For this reason, the photosynthesis of a plant is promoted by the Emerson effect, and the growth of the plant can be promoted.

The infrared reflecting plate 5 has a square or rectangular plate shape in plan view, and its length is substantially the same as the length of the semi-cylindrical reflecting plate 3. The infrared reflecting plate 5 is made of a transparent member that transmits substantially 100% of visible light. The transparent member has a base material made of, for example, a transparent resin or transparent glass, and a transparent conductive material is formed on the surface of the base material. The film is formed by sputtering, vacuum deposition, or sol-gel method. This transparent conductive film is doped with indium oxide doped with tin (In ₂ O ₃ (Sn)), tin oxide (SnO ₂ ), tin oxide doped with fluorine (SnO ₂ (F)), and antimony. Tin oxide (SnO ₂ (Sb)) and the like.

  The infrared reflecting plate 5 having the above shape and configuration is reflected in the space surrounded by the reflecting plate 3 and the infrared limiting plate 4 and between the light source 2 and the reflecting plate 3 above the light source 2. It is arranged in contact with the plate 3. The infrared reflecting plate 5 arranged in this way transmits visible light emitted from the light source 2, and transmits again the visible light transmitted through the self-reflecting plate 5 and reflected by the inner surface 3 a of the reflecting plate 3. Further, the infrared reflecting plate 5 reflects the infrared rays emitted from the light source 2 and the infrared rays reflected by the infrared limiting plate 4 on the lower bottom surface.

  Next, with reference to FIG. 3 (a) (b), the infrared transmittance of the infrared limiting board 4 which changes according to a site | part is demonstrated. The infrared ray limiting plate 4 has the lowest infrared transmittance per unit area of the limiting plate 4 at or near the portion intersecting with the perpendicular V standing from the light emitting portion 21 of the light source 2 to the irradiation surface 4a. And is configured to become higher as the distance from the portion increases. This infrared transmittance, which varies depending on the part, is set according to the distance from the light source 21 of the light source 2. The site | part which intersects with the said perpendicular V is located in the center of the irradiation surface 4a, for example. In this way, the infrared transmittance of the infrared limiting plate 4 is configured to change depending on the part, and the infrared transmittance is adjusted so that the amount of infrared irradiation with respect to the plant P is substantially uniform regardless of the position on the horizontal plane. Yes. Therefore, when there are a plurality of plants P spread on the horizontal plane, infrared rays that promote growth are irradiated to them with a substantially uniform light amount regardless of the position on the horizontal plane, so that the growth of the plurality of plants P is substantially uniform. Can be promoted. The infrared transmittance may be set so that infrared rays are emitted from the irradiation surface 4a of the infrared restriction plate 4 with uniform horizontal illuminance.

  Here, in the infrared limiting plate 4 whose irradiation surface 4a is rectangular, for example, the perpendicular V intersects with the main limiting plate 4 at the center of the irradiation surface 4a, and the infrared transmittance is set to change in four directions from the center. I will explain what I did. In this infrared limiting plate 4, the infrared transmittance is set to T <b> 1 in a rectangular region A <b> 1 that includes a portion intersecting with the perpendicular V and has the same aspect ratio as the plane of the limiting plate 4. In the region A2, which has the same center position as the region A1 and has a frame shape surrounding the region A1, and the outer shape is a rectangle having the above aspect ratio, the infrared transmittance is T2 which is higher than T1. Is set. Similarly, infrared transmittances T3 and T4 are set in each of the regions A3 and A4. These areas A1, A2, A3, and A4 are added together to form one irradiation surface 4a. The distance between the inner side and the outer side of each of the regions A2, A3, and A4 may be the same or different in the short side direction or the long side direction.

  A formula of T1 <T2 <T3 <T4 holds between the infrared transmittances T1, T2, T3, and T4. With the above setting, the infrared transmittance changes in four directions parallel to the short side or the long side as the distance from the center of the irradiation surface 4a increases, and takes four values in one infrared limiting plate 4.

  As described above, in the method of producing the infrared limiting plate 4 in which the infrared transmittance changes depending on the part, for example, a part where the infrared transmittance is desired to be set low is masked, and the infrared reflecting material or the infrared absorbing material is applied to the part. There is a method in which the film is applied thickly, vapor deposited several times to increase the thickness of the infrared reflecting film or infrared absorbing film in the part, or a paint whose infrared transmittance is adjusted is applied over the part. Furthermore, when producing a base material such as transparent glass, an infrared reflecting material or an infrared absorbing material is kneaded to prepare a plurality of base materials having different infrared transmittances, and they are arranged at a desired position to form a single infrared limiting plate. 4 may be produced.

  FIG. 3C shows a first modification of the infrared restriction plate 4. The infrared limiting plate 4 according to the first modification is different from the configuration of the embodiment shown in FIG. 4B in that the infrared transmittance changes only in two directions from the irradiation surface 4a. In the infrared limiting plate 4 according to the first modified example, the infrared transmittance is set to T5 in the rectangular region A5 including the portion intersecting with the perpendicular V and having the same vertical length as the limiting plate 4. Yes. In addition, in the rectangular areas A6 and A6 'whose vertical length is the same as that of the restriction plate 4 with the area A5 interposed therebetween, the infrared transmittance is set to T6 which is higher than T5.

  Similarly, in the regions A7, A7 ′ sandwiching the regions A6, A5, A6 ′, the infrared transmittance is set to T7 which is higher than T6, and further, the regions A7, A6, A5, A6 ′, A7 ′. In the regions A8 and A8 'sandwiching the infrared rays, the infrared transmittance is set to T8 which is a value higher than T7. These regions A8, A7, A6, A5, A6 ', A7', A8 'are added together to form one irradiation surface 4a. The widths of the regions A8, A7, A6, A5, A6 ', A7', A8 'may be the same or different.

  A formula of T5 <T6 <T7 <T8 holds between the infrared transmittances T5, T6, T7, and T8. With the above setting, the infrared transmittance changes in two directions parallel to the short direction as the distance from the center of the irradiation surface 4a increases, and takes four values in one infrared limiting plate 4. Also in this modification, the effect which can suppress the light damage and burning of the leaf surface of the plant P, the effect which can ensure the irradiation amount of infrared rays required for the growth of the plant P, and the growth of a plurality of plants spread on the horizontal plane Can be promoted substantially uniformly.

  FIG. 3D shows a second modification of the infrared restriction plate 4. The infrared limiting plate 4 according to the second modified example is different from the configuration of the first modified example shown in FIG. 3C in that the infrared transmittance of the binary value is different from the four values according to the part, not the four values. It is different in having. In the infrared limiting plate 4 according to the second modified example, the infrared transmittance is set to T9 in the rectangular region A9 including the portion intersecting with the perpendicular V and having the same vertical length as the limiting plate 4. Yes. In addition, in the rectangular regions A10 and A10 'whose vertical length is the same as that of the restriction plate 4 with the region A9 interposed therebetween, the infrared transmittance is set to T10 which is a value higher than T9. These areas A10, A9, A10 'are added together to form a single irradiation surface 4a. The widths of the regions A10, A9, A10 'may be the same or different.

  A formula of T9 <T10 is established between the infrared transmittances T9 and T10. With the above settings, the infrared transmittance changes in two directions parallel to the short direction as the distance from the center of the irradiation surface 4a increases, and takes two values in one infrared limiting plate 4. Also in this modification, the effect which can suppress the light damage and burning of the leaf surface of the plant P, the effect which can ensure the irradiation amount of infrared rays required for the growth of the plant P, and the growth of a plurality of plants spread on the horizontal plane Can be promoted substantially uniformly. Note that the configuration of the infrared limiting plate 4 is not limited to the above-described configuration shown in FIGS. 3B, 3C, and 3D.

  FIGS. 4A and 4B show the irradiation amount of infrared rays that varies depending on the presence or absence of the infrared limiting plate 4 and the infrared reflecting plate 5. As described above, the present apparatus is disposed above the plant P. In the apparatus arranged as described above, when the infrared limiting plate 4 and the infrared reflecting plate 5 are not provided (see FIG. 5A), the amount of infrared rays decreases in inverse proportion to the square of the distance. The amount of irradiation of infrared rays L1 (indicated by block arrows) emitted from the unit 21 and irradiated to the plant P below is increased immediately below the light source 2 and decreased in the vicinity thereof. For this reason, when there are a plurality of plants P that spread on the horizontal plane, the amount of infrared irradiation with respect to the plant P differs depending on the position, and the plant P with a large amount of infrared irradiation grows quickly. Therefore, variation occurs in the speed of growth among the plurality of plants P. In addition, visible light L2 (shown with a broken line) is reflected from the light source 2 directly or by the reflector 3 so that the horizontal illuminance is substantially uniform, and is irradiated to the plant P.

  Next, the amount of infrared irradiation when the infrared limiting plate 4 and the infrared reflecting plate 5 are provided in the present apparatus (see FIG. 4B) will be described. First, the optical path of light emitted from the light source 2 will be described. The light emitted from the light source 2 includes visible light and infrared light. Visible light L <b> 2 (indicated by a broken line) is reflected from the light source 2 directly or by the reflecting plate 3 to make the horizontal illuminance substantially uniform, and is irradiated to the plant P. Infrared light L3 (indicated by a solid line) emitted from the light source 2 and directly reaching the infrared reflecting plate 5 is reflected by the reflecting plate 5. In addition, the infrared ray L4 (indicated by a solid line) that is emitted from the light source 2 and reaches the portion where the infrared transmittance of the infrared limiting plate 4 is low and reflected by the portion is further reflected by, for example, the infrared reflecting plate 5 and travel direction Can be changed. The infrared ray L4 whose traveling direction has been changed is incident on a portion of the infrared restriction plate 4 where the infrared transmittance is high. The infrared ray L4 incident on the part passes through the infrared restriction plate 4. For this reason, infrared rays can be efficiently utilized to irradiate the plant P. Furthermore, since heat does not easily accumulate in the housing 1, the life of the apparatus can be extended.

  As described above, the infrared ray having a large amount of light incident on the infrared ray limiting plate 4 immediately below the light source 2 is transmitted with a limited amount. Moreover, the infrared rays from the light source 2 and the infrared rays reflected by the infrared reflecting plate 5 that are incident on a portion having a high infrared transmittance away from just below the light source 2 are transmitted with a high transmittance. For this reason, it becomes possible to make the light quantity of the infrared rays L1 (indicated by block arrows) that are exposed to the plurality of plants P substantially uniform regardless of the position on the substantially horizontal plane. Therefore, the growth rate of a plurality of plants P extending on a horizontal plane can be made uniform.

  The present invention is not limited to the configuration of the embodiment as described above, and various modifications can be made according to the purpose of use. For example, in the infrared limiting plate 4, the infrared transmittance per unit area of the limiting plate 4 is lowest at or near a portion intersecting with a vertical line standing on the upper surface from the light emitting portion 21 of the light source 2. And it may be comprised so that it may become high as it leaves | separates from this site | part. Moreover, when suppressing the visible light with which the plant P is irradiated, the infrared limiting plate 4 may be one in which an opaque infrared reflecting material is applied or vapor-deposited on a base material such as glass. In the limiting plate 4, the infrared transmittance of the infrared limiting plate 4 varies depending on the location where the infrared reflecting material is present and where it is not.

The disassembled perspective view of the illuminating device for plant cultivation which concerns on one Embodiment of this invention. The figure which shows the cross-sectional structure and use condition of the said apparatus. (A) is an enlarged view of a broken-line frame A portion in FIG. 2, (b) is a plan view of an infrared ray limiting plate of the above device, (c) is a plan view showing a first modification of the limiting plate, (d). FIG. 9 is a plan view showing a second modification of the restriction plate. (A) is a figure which shows the infrared irradiation amount with respect to a plant when the said apparatus is not provided with the infrared limiting board and the infrared reflecting board, (b) is when the said apparatus is provided with the infrared limiting board and the infrared reflecting board. The figure which shows the infrared irradiation amount with respect to a plant.

Explanation of symbols

1 Housing 2 Light source 3 Reflector 4 Infrared limiting plate (infrared limiting member)
4a Irradiation surface 5 Infrared reflector (infrared reflector)
L1, L3, L4 Infrared L2 Visible light V Normal P Plant

Claims (3)

In the plant growth lighting device for irradiating the plant with light to promote the growth of the plant,
The body,
A light source disposed inside the housing and emitting light;
A reflector that reflects visible light and infrared light emitted from the light source;
The infrared light that is disposed between the light source and the plant, transmits visible light emitted from the light source and visible light reflected by the reflector, and is emitted from the light source and reflected by the reflector. An infrared limiting member having an irradiation surface for limiting the amount of transmission and irradiating the plant with light,
The infrared limiting member is configured such that the infrared transmittance per unit area of the member is lowest at a portion where the infrared ray intersects with a vertical line standing on the irradiation surface from the light source, and the amount of infrared irradiation on the plant is substantially reduced. A plant-growing lighting device characterized by being substantially uniform regardless of a position on a horizontal plane.   The infrared ray limiting member is configured such that an infrared transmittance per unit area of the member increases as the distance from the portion intersecting with a perpendicular line standing on the irradiation surface from the light source increases. The plant growing lighting device according to 1. 2. An infrared reflecting member that is disposed between the light source and the reflecting plate and transmits visible light emitted from the light source and reflects infrared light emitted from the light source. Or the illuminating device for plant cultivation of Claim 2.