Optical film, optical compensation film, polarizing plate and liquid crystal display
AssigneeFUJIFILM Corporation
InventorsHajime NAKAYAMA, Hirofumi TOYAMA, Yuta TAKAHASHI
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Abstract
An optical film is provided and has retardations satisfying relations (1) to (3): 0≦Re(550)≦10; (1) −25≦Rth(550)≦25; and (2) |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 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.
Claims11
An optical film having retardations satisfying relations (1) to (3):
- 1≦Re(550)≦5;
- (1)
- −15≦Rth(550)≦15;
- and (2)
- |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-D) to (7-D):
- 0<I≦50;
- (4-D)
- −50≦II<0;
- (5-D)
- −50≦III≦0;
- and (6-D)
- 0≦IV≦50, (7-D)
- wherein a material for forming the optical film comprises an acrylic polymer, or cellulose acylate.
Dependencies are inferred from the claim text.