US 12,216,393 B2
Illumination device and display device
Shingo Ohkawa, Kanagawa (JP); and Gen Yonezawa, Kanagawa (JP)
Assigned to Sony Group Corporation, Tokyo (JP)
Filed by SONY GROUP CORPORATION, Tokyo (JP)
Filed on Nov. 17, 2023, as Appl. No. 18/512,314.
Application 18/512,314 is a continuation of application No. 17/760,734, granted, now 11,829,060, previously published as PCT/JP2020/035485, filed on Sep. 18, 2020.
Claims priority of application No. 2019-173429 (JP), filed on Sep. 24, 2019.
Prior Publication US 2024/0085775 A1, Mar. 14, 2024
Int. Cl. G03B 21/20 (2006.01)
CPC G03B 21/208 (2013.01) 19 Claims
OG exemplary drawing
 
1. An illumination device, comprising:
a plurality of light source assemblies; and
a plate-shaped optical unit, including:
a plurality of transmission surface areas, wherein each of the transmission surface areas has a length that extends parallel to a first direction along the plate-shaped optical unit and a width that extends parallel to a second direction along the plate-shaped optical unit that is orthogonal to the first direction; and
a plurality of reflection surface areas, wherein each of the reflection surface areas has a length that extends parallel to the first direction and a width that extends parallel to the second direction that is orthogonal to the first direction,
wherein the transmission surfaces are interleaved with the reflection surface areas along the second direction,
wherein a width of each transmission surface area in the plurality of transmission surface areas periodically varies with distance along the length of the transmission surface area,
wherein a width of each reflection surface area in the plurality of reflection surface areas periodically varies with distance along the length of the reflection surface area, and
wherein the widths of the transmission surface areas and the reflection surface areas are complementary to one another such that, at a location along the length of the transmission surface area where the width of the transmission surface is equal to a maximum width of the transmission surface area, a width of the reflection surface area at a corresponding location along the length of the reflection surface area is equal to a minimum width of the reflection surface area, and such that, at a location along the length of the transmission surface area where the width of the transmission surface area is equal to a minimum width of the transmission surface area, a width of the reflection surface area at a corresponding location along the length of the reflection surface area is equal to a maximum width of the reflection surface area.