| 摘要 |
PROBLEM TO BE SOLVED: To improve visual angle characteristics in all up and down, and right and left directions of the screen of a liquid crystal display element. SOLUTION: On the projection light side of a liquid crystal cell 4, a light scattering plate 3, a 1st negative phase difference plate 2, and a 1st polarizing plate 1 are arranged in order and on the incident light side, a 2nd negative phase difference plate 5 and a 2nd polarizing plate 6 are arranged in order; and the twist angle of liquid crystal is 240 deg., Δnd of the liquid crystal 865nm, the angle of the absorption axis of the 1st polarizing plate 1 10 deg., the angle of the elongation axis of the 1st phase difference plate 2 70 deg., the angle of the elongation axis of the 2nd phase difference plate 5 110 deg., the angle of the absorption axis of the 2nd polarizing plate 6 80 deg., the sum of Δnd's of two phase difference plates 2 870nm, and the coefficients of vertical orientation Nz of the phase difference plates 2 and 5 is 0.1-0.7. The light scattering plate 3 is so arranged that light is scattered in directions of θ=90-270 deg. and its scattering angle is ϕ=10-80 deg.. Two prism sheets of a back light has a 90 deg. V-shape angle of V- sectioned grooves, the respective prism sheets are laminated and arranged having their grooves orthogonally, and a diffusion sheet and a light guide plate is arranged in order beneath the two prism sheets. |
