US 12,253,705 B2
Polarizing plate and optical display apparatus comprising the same
Bong Choon Kim, Suwon-si (KR); Jun Mo Koo, Suwon-si (KR); Dong Yoon Shin, Suwon-si (KR); Jung Hun You, Suwon-si (KR); and Sang Hum Lee, Suwon-si (KR)
Assigned to Samsung SDI Co., Ltd., Yongin-si (KR)
Filed by Samsung SDI Co., Ltd., Yongin-si (KR)
Filed on Jul. 21, 2021, as Appl. No. 17/381,550.
Claims priority of application No. 10-2020-0091948 (KR), filed on Jul. 23, 2020.
Prior Publication US 2022/0026614 A1, Jan. 27, 2022
Int. Cl. G02B 5/30 (2006.01); G02B 1/04 (2006.01); G02F 1/13363 (2006.01)
CPC G02B 5/3083 (2013.01) [G02B 1/04 (2013.01); G02B 5/305 (2013.01); G02F 1/13363 (2013.01); C09K 2323/00 (2020.08); C09K 2323/03 (2020.08); C09K 2323/031 (2020.08)] 17 Claims
OG exemplary drawing
 
1. A polarizing plate comprising: a polarizer; and a first retardation layer and a second retardation layer sequentially stacked on a lower surface of the polarizer,
wherein the first retardation layer has an in-plane retardation of about 180 nm to about 220 nm at a wavelength of about 550 nm,
the second retardation layer has an in-plane retardation of about 80 nm to about 100 nm at a wavelength of about 550 nm and a degree of biaxiality (NZ) of about −0.5 to −0.2 at a wavelength of about 550 nm,
the first retardation layer exhibits positive wavelength dispersion or flat wavelength dispersion,
the first retardation layer has a slow axis tilted at an angle of about +55° to about +80° or at an angle of about −80° to about −55° with reference to a transmission axis of the polarizer, and
the polarizing plate has an ellipticity of about 65% or more at an incidence angle of about 60°.