Reflective articles and methods for increasing photosynthesis

• US 10,575,476 B2
• Filed: 04/22/2016
• Issued: 03/03/2020
• Est. Priority Date: 12/20/2013
• Status: Active Grant

• Current Assignee: Elwha LLC (Intellectual Ventures LLC)
• Original Assignee: Elwha LLC (Intellectual Ventures LLC)
• Inventors: Duncan, William David, Hyde, Roderick A., Ishikawa, Muriel Y., Wood, Jr., Lowell L.
• Primary Examiner(s): Pinkney, Dawayne
• Application Number:
  US15/136,459
• Publication Number:
  US 20160309660A1
• Time in Patent Office: 1,411 Days
• Field of Search: 359244, 359515, 359529, 359530, 359542, 359599, 359618, 359831, 359833-834, 359836
• CPC Class Codes: A01G 15/00 Devices or methods for influencing weather conditions
• CPC Class Codes: A01G 9/243 Collecting solar energy in general F24S
• CPC Class Codes: G02B 19/0019 having reflective surfaces only (e.g. louvre systems, systems with multiple planar reflectors)
• CPC Class Codes: G02B 19/0042 for use with direct solar radiation
• CPC Class Codes: G02B 27/143 using macroscopically faceted or segmented reflective surfaces
• CPC Class Codes: G02B 5/0236 the diffusion taking place within the volume of the element
• CPC Class Codes: G02B 5/0257 creating an anisotropic diffusion characteristic, i.e. distributing output differently in two perpendicular axes
• CPC Class Codes: G02B 5/0284 used in reflection
• CPC Class Codes: G02B 5/0294 adapted to provide an additional optical effect, e.g. anti-reflection or filter
• CPC Class Codes: G02B 5/124 plural reflecting elements forming part of a unitary plate or sheet
• CPC Class Codes: G02F 1/0126 Opto-optical modulation, i.e. control of one light beam by another light beam, not otherwise provided for in this subclass
• CPC Class Codes: G02F 1/0147 based on thermo-optic effects G02F1/132 takes precedence
• CPC Class Codes: Y02A 40/25 Greenhouse technology, e.g. cooling systems therefor
• CPC Class Codes: Y02P 60/12 using renewable energies, e.g. solar water pumping

Abstract

Provided is a reflective article including a first reflecting material and a second retro reflecting material; where sunlight that is photosynthetically active is at least partially reflected by the article and sunlight that is not photosynthetically active is at least partially retro reflected by the article. Also provided is a method for growing a plant, where the method includes placing the reflective article under, around, or in the proximity of the plant.

Claims

1. A reflective article comprising:

a first layer including reflecting material configured to diffusely reflect incident sunlight that is photosynthetically active; and

a second layer including retro-reflecting material configured to retro-reflect incident sunlight that is non-photosynthetically active, the retro-reflecting material having a reflection coefficient corresponding to a proportion of energy of the incident sunlight that is non-photosynthetically active that the retro-reflecting material retro-reflects, the reflection coefficient increases with at least one of an increase of a temperature of the article or an increase of a quantity of sunlight that contacts the article;

wherein the first layer covers the second layer such that incident light strikes the first layer before reaching the second layer.

2. The reflective article of claim 1, wherein the retro-reflecting material comprises corner-cube reflectors.

3. The reflective article of claim 2, wherein the corner-cube reflectors are about 0.1 cm to 10.0 cm or about 0.01 cm wide.

4. The reflective article of claim 1, wherein the retro-reflecting material includes metal coated plastic.

5. The reflective particle of claim 1, wherein at least one of the first layer or the second layer includes a polymer.

6. The reflective article of claim 5, wherein the polymer is biodegradable.

7. The reflective article of claim 1, wherein the reflective article includes Viagrow™

Lightite Diamond Reflective Mylar Film, a double wavelength-reflective multi-layer film, or a Panda film.

8. The reflective article of claim 1, wherein the increase occurs abruptly at about 5°

C.

9. The reflective article of claim 1, wherein the increase occurs gradually at a temperature greater than about 5°

C.

10. The reflective article of claim 1, wherein at least 80% of incident sunlight that is photosynthetically active is reflected by the article at 27°

C.

11. The reflective article of claim 1, wherein at least 80% of incident sunlight that is non-photosynthetically active is retro-reflected at 27°

C.

12. The reflective article of claim 1, wherein the reflecting material includes reflecting particles having a diameter of less than about 100 μ

m.

13. The reflective article of claim 12, wherein the reflecting particles are thermochromics.

14. The reflective article of claim 12, wherein the reflecting particles include plastic or SiO₂.

15. The reflective article of claim 1, wherein the reflective article reduces the thermal emissivity of the ground it covers.

16. The reflective article of claim 15, wherein the reflective article reduces the thermal emissivity of the ground that it covers by about 1% to about 75%.

17. The reflective article of claim 15, wherein the reflective article reduces the thermal emissivity of the ground that it covers by about 25% to about 50%.

18. The reflective article of claim 1, wherein the reflective article scatters incident sunlight that is not photosynthetically active with a dissipation coefficient that increases with at least one of the temperature of the reflective article or the quantity of sunlight that contacts the article.

19. The reflective article of claim 18, wherein the dissipation coefficient increases abruptly at approximately 5°

C.