摘要 |
PURPOSE:To deepen the display color and to enable a clear color display of high contrast on a background making the contrast of color distinct by considerably increasing the light absorptance of a polychromatic dye to the quantity of transmitted light while using a homeotropically oriented nematic liq. crystal. CONSTITUTION:By adding 2-methylbutyl-4'-(2-methylbutyl)-4-biphenyl carboxylate to a homeotropically oriented nematic liq. crystal contg. a polychromatic dye, planar arrangement is provided when a voltage is applied. The chiral nematic liq. crystal is added in an amount required to keep the nematic liq. crystal in the state of homeotropic orientation when no voltage is applied and to place it in a state of planar orientation when a voltage is applied. That is, the spiral pitch of the liq. crystal in the state of planar orientation is made to <=2 times, preferably about 1 time as large as the thickness of the liq. crystal layer. |