US 12,174,489 B2
Optical sheet laminate, backlight unit, liquid crystal display device, information equipment, and production method for backlight unit
Chengheng Tsai, Tokyo (JP)
Assigned to KEIWA INCORPORATED, Tokyo (JP)
Filed by KEIWA Incorporated, Tokyo (JP)
Filed on Mar. 1, 2024, as Appl. No. 18/593,773.
Application 18/593,773 is a continuation of application No. PCT/JP2022/019123, filed on Apr. 27, 2022.
Claims priority of application No. 2021-146804 (JP), filed on Sep. 9, 2021.
Prior Publication US 2024/0201539 A1, Jun. 20, 2024
Int. Cl. G02F 1/13357 (2006.01); G02B 5/02 (2006.01); G02B 5/04 (2006.01); G02F 1/1335 (2006.01)
CPC G02F 1/133606 (2013.01) [G02B 5/0278 (2013.01); G02B 5/045 (2013.01); G02F 1/133607 (2021.01)] 10 Claims
OG exemplary drawing
 
1. An optical sheet laminate to be incorporated into a backlight unit, comprising:
a plurality of diffusion sheets each comprising surfaces, at least one of which has a plurality of recesses comprising a substantially inverted quadrangular pyramid shape and arranged in a two-dimensional matrix; and
a pair of prism sheets comprising prism extending directions perpendicular to each other,
wherein
the plurality of diffusion sheets include at least two diffusion sheets where an arrangement direction of the plurality of recesses of one of the at least two diffusion sheets is different from that of the plurality of recesses of another one of the at least two diffusion sheets.