US 12,320,478 B2
Lighting device
Kojiro Ikeda, Tokyo (JP); Takeo Koito, Tokyo (JP); and Keiji Takizawa, Tokyo (JP)
Assigned to Japan Display Inc., Tokyo (JP)
Filed by Japan Display Inc., Tokyo (JP)
Filed on Aug. 7, 2024, as Appl. No. 18/796,776.
Application 18/796,776 is a continuation of application No. PCT/JP2023/000297, filed on Jan. 10, 2023.
Claims priority of application No. 2022-023969 (JP), filed on Feb. 18, 2022.
Prior Publication US 2024/0392934 A1, Nov. 28, 2024
Int. Cl. F21K 9/65 (2016.01); F21V 14/00 (2018.01); F21Y 105/18 (2016.01); F21Y 113/13 (2016.01); F21Y 115/10 (2016.01)
CPC F21K 9/65 (2016.08) [F21V 14/003 (2013.01); F21Y 2105/18 (2016.08); F21Y 2113/13 (2016.08); F21Y 2115/10 (2016.08)] 6 Claims
OG exemplary drawing
 
1. A lighting device comprising:
a light source comprising at least two types of light emitting elements with different color temperatures;
an optical element comprising a plurality of liquid crystal cells, the optical element configured to control a distribution of light emitted from the light source; and
a control unit configured to control the light source,
wherein the control unit controls the optical element to change from a first light distribution state to a second light distribution state different from the first light distribution state,
the control unit controls the light source so that a color temperature of light emitted in a direction perpendicular to a surface of the optical element is the same in the first light distribution state and the second light distribution state, and
the control unit controls the light source based on a voltage applied to the optical element for controlling a distribution angle of the light emitted from the optical element.