System for selective irradiation with circularly polarized light

• US 9,955,633 B2
• Filed: 11/26/2014
• Issued: 05/01/2018
• Est. Priority Date: 05/28/2012
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Ichihashi, Mitsuyoshi, Usami, Yoshihisa
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): LEE, NATHANIEL J.
• Application Number:
  US14/554,305
• Publication Number:
  US 20150075069A1
• Time in Patent Office: 1,252 Days
• CPC Class Codes: A01G 7/045 with electric lighting
• CPC Class Codes: A01G 9/14 Greenhouses cloches A01G13/04
• 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: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 27/286 for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34
• CPC Class Codes: Y02P 60/14 Measures for saving energy, e.g. in green houses

Abstract

According to the present invention, provided is a system for irradiating a target object selectively with specific circularly polarized light, comprising a polarization-state control member that controls the polarization state of light to thereby generate circularly polarized light; and a circularly polarized light-reflecting member, wherein the circularly polarized light-reflecting member is disposed at a position on which the circularly polarized light emitted from the polarization-state control member can be incident; the circularly polarized light-reflecting member generates reflected light that selectively comprises circularly polarized light of the same sense as the incident circularly polarized light from the polarization-state control member; and the circularly polarized light-reflecting member is disposed such that the target object can be irradiated with at least a part of the reflected light.

Claims

1. A system for irradiating a target object selectively with circularly polarized light in one sense, comprising a polarization-state control member that controls the polarization state of light to thereby generate circularly polarized light, and a circularly polarized light-reflecting member, wherein

the circularly polarized light-reflecting member is disposed at a position on which the circularly polarized light emitted from the polarization-state control member can be incident;

the circularly polarized light-reflecting member generates reflected light that comprises circularly polarized light of the same sense as the incident circularly polarized light from the polarization-state control member; and

the circularly polarized light-reflecting member is disposed such that the target object can be irradiated with the reflected light circularly polarized only in one sense.

2. The system according to claim 1 used as a structure, wherein the structure comprises a space containing the polarization-state control member and the circularly polarized light-reflecting member;

the space is formed by faces having the circularly polarized light-reflecting member at least in part; and

10% or more of the area of the faces forming the space has the circularly polarized light-reflecting member.

3. The system according to claim 2, including the circularly polarized light-reflecting member in 50% or more of the area of the faces forming the space.

4. The system according to claim 3 used as a plant factory, wherein the plant factory comprises a space formed by a wall face, a ceiling and a floor, and comprises the polarization-state control member and the circularly polarized light-reflecting member inside the space;

and 10% or more of the total area of the wall face, the ceiling and the floor is the circularly polarized light-reflecting member.

5. The system according to claim 2, wherein the circularly polarized light-reflecting member is disposed at a position on which the circularly polarized light produced by passing through the polarization-state control member can be incident.

6. The system according to claim 5 used as a plant factory, wherein the plant factory comprises a space formed by a wall face, a ceiling and a floor, and comprises the polarization-state control member and the circularly polarized light-reflecting member inside the space;

and 10% or more of the total area of the wall face, the ceiling and the floor is the circularly polarized light-reflecting member.

7. The system according to claim 1, wherein the polarization-state control member comprises a linearly-polarizing plate and a quarter wave plate.

8. The system according to claim 7 used as a plant factory, wherein the plant factory comprises a space formed by a wall face, a ceiling and a floor, and comprises the polarization-state control member and the circularly polarized light-reflecting member inside the space;

and 10% or more of the total area of the wall face, the ceiling and the floor is the circularly polarized light-reflecting member.

9. The system according to claim 1, wherein the polarization-state control member comprises a layer having a helical molecular arrangement structure.

10. The system according to claim 9, wherein the circularly polarized light-reflecting member comprises a layer having a helical molecular arrangement structure.

11. The system according to claim 9 used as a plant factory, wherein the plant factory comprises a space formed by a wall face, a ceiling and a floor, and comprises the polarization-state control member and the circularly polarized light-reflecting member inside the space;

and 10% or more of the total area of the wall face, the ceiling and the floor is the circularly polarized light-reflecting member.

12. The system according to claim 10 used as a plant factory, wherein the plant factory comprises a space formed by a wall face, a ceiling and a floor, and comprises the polarization-state control member and the circularly polarized light-reflecting member inside the space;

and 10% or more of the total area of the wall face, the ceiling and the floor is the circularly polarized light-reflecting member.

13. The system according to claim 1, wherein the target object is a plant.

14. The system according to claim 1, wherein the system has a light source;

and the polarization-state control member controls the polarization state of light generated from the light source to thereby produce circularly polarized light.

15. The system according to claim 14 used as a plant factory, wherein the plant factory comprises a shelf of 2 or more stages;

a space between a bottom face and a bottom face of an upper stage in at least one stage of the shelf comprises the light source, the polarization-state control member and the circularly polarized light-reflecting member; and

10% or more of the total area of either one or more faces on the space side selected from the bottom face and the bottom face of an upper stage is the circularly polarized light-reflecting member.

16. The system according to claim 15, wherein the polarization-state control member comprises a linearly-polarizing plate and a quarter wave plate.

17. The system according to claim 15, wherein the polarization-state control member comprises a layer having a helical molecular arrangement structure.

18. The system according to claim 17, wherein the circularly polarized light-reflecting member comprises a layer having a helical molecular arrangement structure.

19. The system according to claim 1 used as a plant factory, wherein the plant factory comprises a space formed by a wall face, a ceiling and a floor, and comprises the polarization-state control member and the circularly polarized light-reflecting member inside the space;

and 10% or more of the total area of the wall face, the ceiling and the floor is the circularly polarized light-reflecting member.

20. A method for cultivating a plant using the system according to claim 1.