US 11,889,803 B2
Plant growth lighting fixture
Satoshi Kuniyasu, Minamiashigara (JP); and Ryosuke Shimizu, Minamiashigara (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on May 19, 2021, as Appl. No. 17/324,196.
Application 17/324,196 is a continuation of application No. PCT/JP2019/043780, filed on Nov. 8, 2019.
Claims priority of application No. 2018-234354 (JP), filed on Dec. 14, 2018.
Prior Publication US 2021/0267139 A1, Sep. 2, 2021
Int. Cl. A01G 9/24 (2006.01); F21V 9/40 (2018.01); A01G 7/04 (2006.01); F21V 9/14 (2006.01); G02B 5/30 (2006.01); F21Y 115/10 (2016.01)
CPC A01G 9/249 (2019.05) [A01G 7/045 (2013.01); F21V 9/14 (2013.01); F21V 9/40 (2018.02); G02B 5/3016 (2013.01); F21Y 2115/10 (2016.08)] 11 Claims
OG exemplary drawing
 
1. A plant growth lighting fixture comprising:
light sources; and
a reflective-type circularly polarizing plate having cholesteric liquid crystal layers formed by fixing a cholesteric liquid crystalline phase,
wherein when a wavelength range of 380 nm or more and 500 nm or less is a blue wavelength range, a wavelength range of more than 500 nm and less than 600 nm is a green wavelength range, and a wavelength range of 600 nm or more and 780 nm or less is a red wavelength range,
the light sources have two or more of a blue light source having an emission center wavelength in the blue wavelength range, a green light source having an emission center wavelength in the green wavelength range, and a red light source having an emission center wavelength in the red wavelength range,
the reflective-type circularly polarizing plate has two or more of a blue-reflecting cholesteric liquid crystal layer having a center wavelength of an effective wavelength range in the blue wavelength range, a green-reflecting cholesteric liquid crystal layer having a center wavelength of an effective wavelength range in the green wavelength range, and a red-reflecting cholesteric liquid crystal layer having a center wavelength of an effective wavelength range in the red wavelength range,
the wavelength ranges of the emission center wavelengths as the light sources and the wavelength ranges of the center wavelength of the effective wavelength range as the reflective-type circularly polarizing plate are wavelength ranges of the same colors, and
the reflective-type circularly polarizing plate has a polarization correction layer having a phase difference in a thickness direction.