CIRCULAR POLARIZATION ILLUMINATION DEVICE AND PLANT GROWTH REGULATION METHOD

• US 20140041295A1
• Filed: 10/21/2013
• Published: 02/13/2014
• Est. Priority Date: 04/22/2011
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: USAMI, Yoshihisa, ICHIHASHI, Mitsuyoshi, TAKEUCHI, Yohsuke
• Granted Patent: US 9,848,540 B2
• Time in Patent Office: Days
• US Class Current: 47/58.1LS
• CPC Class Codes: A01G 7/045 with electric lighting
• CPC Class Codes: A01G 9/249 Lighting means with special arrangements for promoting growth A01G7/045
• CPC Class Codes: F21V 9/14 for producing polarised light
• CPC Class Codes: Y02P 60/14 Measures for saving energy, e.g. in green houses

Abstract

The present invention provides a circular polarization illumination device which can irradiate right-circularly polarized light at a large light amount from a light source of right-circularly polarized light with a high efficiency and can irradiate left-circularly polarized light at a large light amount from a light source of left-circularly polarized light with a high efficiency, and a plant growth regulation method that can efficiently regulate the promotion or inhibition of the growth of plants by using the circular polarization illumination device. Moreover, the illumination device includes a light-emitting light source, a reflective polarizing plate, reirradiation unit, and circular polarization conversion unit.

Claims

1. A circular polarization illumination device comprising:

a light-emitting light source;

a reflective polarizing plate that transmits one of the polarization components of incident light from the light-emitting light source and reflects the other polarization component;

reirradiation unit for changing a polarization state of the light reflected from the reflective polarizing plate to reirradiate the reflective polarizer with the light; and

circular polarization conversion unit for converting the light having been transmitted through the reflective polarizing plate into circularly polarized light.

2. The circular polarization illumination device according to claim 1, further comprising a member that functions as the reflective polarizing plate and the unit for conversion into circularly polarized light at the same time.

3. The circular polarization illumination device according to claim 1, further comprising a birefringent member that can change the polarization state.

4. The circular polarization illumination device according to claim 2, further comprising a birefringent member that can change the polarization state.

5. The circular polarization illumination device according to claim 1, further comprising a scattering member that can change the polarization state.

6. The circular polarization illumination device according to claim 2, further comprising a scattering member that can change the polarization state.

7. A plant growth regulation method using the circular polarization illumination device according to claim 1 as an irradiation light source.

8. A plant growth regulation method using the circular polarization illumination device according to claim 2 as an irradiation light source.

9. A plant growth regulation method using the circular polarization illumination device according to claim 3 as an irradiation light source.

10. A plant growth regulation method using the circular polarization illumination device according to claim 4 as an irradiation light source.

11. A plant growth regulation method using the circular polarization illumination device according to claim 5 as an irradiation light source.

12. A plant growth regulation method using the circular polarization illumination device according to claim 6 as an irradiation light source.