US 12,292,593 B2
Lighting device
Makoto Hasegawa, Tokyo (JP); and Masafumi Okada, Tokyo (JP)
Assigned to Japan Display Inc., Tokyo (JP)
Filed by Japan Display Inc., Tokyo (JP)
Filed on Aug. 8, 2023, as Appl. No. 18/366,773.
Application 18/366,773 is a continuation of application No. PCT/JP2021/044267, filed on Dec. 2, 2021.
Claims priority of application No. 2021-019581 (JP), filed on Feb. 10, 2021.
Prior Publication US 2023/0375775 A1, Nov. 23, 2023
Int. Cl. F21V 8/00 (2006.01)
CPC G02B 6/0073 (2013.01) [G02B 6/0036 (2013.01); G02B 6/0053 (2013.01); G02B 6/0075 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A lighting device comprising:
a first light guide plate on which a plurality of first light-emitting diodes are arranged at a first side surface along a first direction; and
a second light guide plate on which a plurality of second light-emitting diodes are arranged at a second side surface along the first direction, the first light guide plate and the second light guide plate being overlappingly arranged, wherein
the first light guide plate has a first area extending in a second direction perpendicular to the first direction and a third area extending in the second direction and adjacent to the first area,
a first prism array is formed under a bottom surface of the first area,
a prism array is not formed under a bottom surface of the third area,
the second light guide plate has a second area extending in the second direction and a fourth area extending in the second direction and adjacent to the second area,
a second prism array is formed under a bottom surface of the second area,
a prism array is not formed under a bottom surface of the fourth area,
when seen in a plan view, the first area and the fourth area overlap, and the second area and the third area overlap, and
a prism height of the prism array in the second area is taller than a prism height of the prism arrays in the first area.