US 11,789,312 B2
Lighting device and display device
Hirotoshi Yasunaga, Kameyama (JP); Hisashi Watanabe, Kameyama (JP); and Takeshi Masuda, Kameyama (JP)
Assigned to Sharp Display Technology Corporation, Kameyama (JP)
Filed by Sharp Display Technology Corporation, Kameyama (JP)
Filed on Nov. 15, 2022, as Appl. No. 17/987,803.
Claims priority of application No. 2021-192675 (JP), filed on Nov. 29, 2021.
Prior Publication US 2023/0168540 A1, Jun. 1, 2023
Int. Cl. G02F 1/13357 (2006.01); F21V 8/00 (2006.01)
CPC G02F 1/133606 (2013.01) [G02B 6/0076 (2013.01); G02F 1/133605 (2013.01); G02F 1/133603 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A lighting device comprising:
a plurality of light sources; and
a plurality of optical sheets disposed to be stacked at a position away from the plurality of light sources, wherein
the plurality of optical sheets includes a first optical sheet and a second optical sheet,
each of the first optical sheet and the second optical sheet has a unit region that modulates light emitted from a corresponding light source in the plurality of light sources,
each unit region includes a modulation region including a light source region that faces the corresponding light source and that has a relatively high modulation action of the light compared to regions other than the modulation region in each unit region,
a first modulation region, which is the modulation region provided on the first optical sheet, and a second modulation region, which is the modulation region provided on the second optical sheet, are superimposed at least in the light source regions of each other,
the plurality of optical sheets further includes a third optical sheet that has a plurality of unit regions including a third modulation region, which has a same function as the modulation region, associated with each of the plurality of light sources, and
the third modulation region provided on the third optical sheet includes a light source region that overlaps a light source region of the first modulation region of the first optical sheet and a light source region of the second modulation region of the second optical sheet when aligned with the plurality of light sources.