Optical film, optical compensation film, polarizing plate and liquid crystal display

摘要

An optical film is provided and has retardations satisfying relations (1) to (3):
0≦Re(550)≦10;  (1)−25≦Rth(550)≦25;  (2)and|I|+|II|+|III|+|IV|>0.5 (nm),  (3)
with definitions:
I=Re(450)−Re(550);II=Re(650)−Re(550);III=Rth(450)−Rth(550); andIV=Rth(650)−Rth(550),

wherein Re(450), Re(550) and Re(650) are in-plane retardations measured with lights of wavelength of 450, 550 and 650 nm, respectively; and Rth(450), Rth(550) and Rth(650) are retardations in a thickness direction of the optical film, which are measured with lights of wavelength of 450, 550 and 650 nm, respectively.

主权项

1. An optical film having retardations satisfying relations (1) to (3):
0≦Re(550)≦5;  (1) −15≦Rth(550)≦15;  (2) and |I|+|II|+|III|+|IV|>0.5 (nm),  (3)with definitions:
I=Re(450)−Re(550); II=Re(650)−Re(550); III=Rth(450)−Rth(550); and IV=Rth(650)−Rth(550), wherein Re(450), Re(550) and Re(650) are in-plane retardations of 450, 550 and 650 nm, respectively; and Rth(450), Rth(550) and Rth(650) are retardations in a thickness direction of the optical film, which are of wavelength of 450, 550 and 650 nm, respectively, and wherein I, II, III and IV satisfy relations (4-C) to (7-C):
0≦I≦50;  (4-C)−50≦II≦0;  (5-C)0