Patent ID: 6429920
Filing Date: 2002-08-06
Classification: G02F

Abstract:
A reflecting type liquid crystal display device of NB mode comprising:an STN type liquid crystal cell; a first phase difference plate; a second phase difference plate; a polarizing plate, the first phase difference plate, second phase difference plate and polarizing plate being disposed in this order on one surface of the STN type liquid crystal cell; and reflecting means disposed on the other surface of the STN type liquid crystal cell, wherein a product &Dgr;nLCÂ·dLC of birefringence &Dgr;nLC and thickness dLC of a liquid crystal layer of the liquid crystal cell is selected from a range of 660 nm to 830 nm, a product &Dgr;n1Â·d1 of birefringence &Dgr;n1 and thickness d1 of the first phase difference plate is selected from a range of 120 nm to 240 nm, and a product &Dgr;n2Â·d2 of birefringence &Dgr;n2 and thickness d2 of the second phase difference plate is selected from a range of 300 nm to 430 nm, and wherein in the case where a twist direction of a major axis of liquid crystal molecules of the liquid crystal layer of the liquid crystal cell from the reflecting means side to the first phase difference plate side is assumed to be a positive direction, a twist angle &khgr; of liquid crystal molecules from a major axis of the reflecting means side liquid crystal molecules of the liquid crystal layer of the liquid crystal cell to a major axis of the first phase difference plate side liquid crystal molecules of the liquid crystal layer of the liquid crystal cell is selected from a range of 220Â° to 260Â°, an angle &thgr; from a major axis of the first phase difference plate side liquid crystal molecules of the liquid crystal layer of the liquid crystal cell to a slow axis of the first phase difference plate is selected from a range of âˆ’130Â° to âˆ’75Â°, an angle &phgr; from the slow axis of the first phase difference plate to a slow axis of the second phase difference plate is selected from a range of âˆ’20Â° to âˆ’60Â°, and an angle &phgr; from the slow axis of the second phase difference plate to an absorption axis of the polarizing plate is selected from a range of âˆ’15Â° to âˆ’45Â°.