Light control device for stimulating plant growth and method thereof

• US 10,667,467 B2
• Filed: 01/24/2019
• Issued: 06/02/2020
• Est. Priority Date: 01/24/2018
• Status: Active Grant

• Current Assignee: Nano and Advanced Materials Institute Limited
• Original Assignee: Nano and Advanced Materials Institute Limited
• Inventors: Kwok, Chi Ho, Hsu, Mei Mei, Liu, Chenmin
• Primary Examiner(s): Breval, Elmito
• Application Number:
  US16/255,856
• Publication Number:
  US 20190223387A1
• Time in Patent Office: 495 Days
• Field of Search: None
• CPC Class Codes: A01G 7/045 with electric lighting
• CPC Class Codes: A01G 9/20 Forcing-frames; Lights , i.e. glass panels covering the forcing-frames
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21S 4/28 rigid, e.g. LED bars
• CPC Class Codes: F21V 9/38 Combination of two or more photoluminescent elements of different materials
• CPC Class Codes: F21V 9/45 by adjustment of photoluminescent elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 15/00 Optical objectives with means for varying the magnification anamorphotic objectives G02B13/08
• CPC Class Codes: G02B 26/008 in the form of devices for effecting sequential colour changes, e.g. colour wheels
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: Y02P 60/14 Measures for saving energy, e.g. in green houses

Abstract

A light control device and method for stimulating plant growth is disclosed. The light control device includes a light source capable of emitting light required for plant growth. The light control device further comprises a plurality of light conversion films rotatably mounted upon a film switching unit arranged around the light source, the film switching unit driven by a motor arranged therewithin. The plurality of light conversion films may further provide a plurality of light spectra required during a plurality of plant growth stages. The light control device determines plant growth stage based on the size and the height of the plants. The motor rotates the film switching unit, based on the plant growth stage of the plants, in such a manner that a light conversion film, associated with the plant growth stage of the plants, is positioned in front of the light source. Such positioning stimulates the plant growth.

Claims

1. A light control device for stimulating plant growth, wherein the light control device comprises:

a light source capable of emitting light required for plant growth;

a plurality of light conversion films rotatably mounted upon a film switching unit arranged around the light source, wherein the film switching unit is driven by a motor arranged therewithin, and wherein the plurality of light conversion films provide a plurality of light spectra required during a plurality of plant growth stages;

a growth monitoring unit configured to monitor size and height of plants under observation; and

a determining unit to determine a plant growth stage based on the size and the height of the plants;

wherein the motor rotates the film switching unit, based on the plant growth stage of the plants, in such a manner that a light conversion film, associated with the plant growth stage of the plants, is positioned in front of the light source, and wherein such positioning enables the light emitted from the light source to pass through the light conversion film and falls on the plants with a light spectrum required for stimulating the plant growth.

2. The light control device of claim 1, wherein the light conversion film comprises a light conversion material and a polymer carrier.

3. The light control device of claim 2, wherein the light conversion material comprises quantum dots (QDs), organic/inorganic phosphors, a combination of QD and phosphors organic light conversion molecules, or inorganic light conversion complexes.

4. The light control device of claim 2, wherein the light conversion material comprises at least one adhesive material selected from the group consisting of silicone, modified silicone, epoxy, modified epoxy, Poly(methyl methacrylate) (PMMA), and Polycarbonate (PC).

5. The light control device of claim 2, wherein the polymer carrier comprises a polymer nanofiber mat or a polymer film.

6. The light control device of claim 1, wherein the plurality of plant growth stages comprises at least one selected from the group consisting of seeding, vegetation, flowering and fruiting.

7. The light control device of claim 1, wherein the light source comprises one or more light emitting diodes (LEDs), wherein the LEDs emit light spectrum with peak value in the range of 400-470 nm in order to drive the light conversion film.

8. The light control device of claim 7, wherein light emitted from the light conversion film improves growth rate of plants by 50% and/or initiates generation of anthocyanin in plants.

9. The light control device of claim 1, further comprises a light guide plate to generate a planar light source, wherein the light guide plate is disposed on both sides of the light source and the light conversion film.

10. The light control device of claim 1, wherein the film switching unit comprises a drum-shaped rotary film switching unit or spherical rotary film switching unit.

11. A method for stimulating plant growth, wherein the method comprises:

providing a light source capable of emitting light required for plant growth;

providing a plurality of light conversion films rotatably mounted upon a film switching unit arranged around the light source, wherein the film switching unit is driven by a motor arranged therewithin, and wherein the plurality of light conversion films provide a plurality of light spectra required during a plurality of plant growth stages;

monitoring, by a growth monitoring unit, size and height of the plants under observation; and

determining, by a determining unit, a plant growth stage based on the size and the height of the plants;

wherein the motor rotates the film switching unit, based on the plant growth stage of the plants, in such a manner that a light conversion film, associated with the plant growth stage of the plants, is positioned in front of the light source, and wherein such positioning enables the light emitted from the light source to pass through the light conversion film and falls on the plants with a light spectrum required for stimulating the plant growth.

12. The method of claim 11, wherein the light conversion film comprises a light conversion material and a polymer carrier.

13. The method of claim 12, wherein the light conversion material comprises quantum dots (QDs), organic/inorganic phosphors, a combination of QD and phosphors organic light conversion molecules, or inorganic light conversion complexes.

14. The method of claim 12, wherein the light conversion material comprises at least one adhesive material selected from the group consisting of silicone, modified silicone, epoxy, modified epoxy, Poly(methyl methacrylate) (PMMA), and Polycarbonate (PC).

15. The method of claim 12, wherein the polymer carrier comprises a polymer nanofiber mat or a polymer film.

16. The method of claim 11, wherein the plurality of plant growth stages comprises at least one selected from the group consisting of seeding, vegetation, flowering and fruiting.

17. The method of claim 11, wherein the light source comprises one or more light emitting diodes (LEDs), wherein the LEDs emit light spectrum with peak value in the range of 400-470 nm in order to drive the light conversion film.

18. The method of claim 17, wherein light emitted from the light conversion film improves growth rate of plants by 50% and/or initiates generation of anthocyanin in plants.

19. The method of claim 11, further comprising providing a light guide plate to generate a planar light source, wherein the light guide plate is disposed on both sides of the light source and the light conversion film.

20. The method of claim 11, wherein the film switching unit comprises a drum-shaped rotary film switching unit or spherical rotary film switching unit.