| 摘要 |
PURPOSE:To obtain an excellent gradational display and a projection image with a little color deviation by using liquid crystal to which dichroic coloring matter having a 580-650nm wavelength of absorption is added and mixed for a twisted nematic liquid crystal valve. CONSTITUTION:A projection display device consists of three twisted nematic (TN) liquid crystal light valves equipped with polarizing plates 1 which form images by using color beams of red, green, and blue, an optical system which mixes the color light beams, and a projection optical system; and the TN liquid crystal 5 to which the dichroic coloring matter 5 having a 580-650nm main wavelength of absorption is used for the three TN liquid crystal valves. Further, 0.5-3.0wt% dichroic coloring matter 4 is added and mixed. The dichroic coloring matter 4 has its long-axis direction arrayed in parallel to molecule axes of the liquid crystal and incident light is absorbed according to the coefficient of absorption in the long-axis direction of the coloring matter when propagated in the liquid crystal in the absence of an electric field and at the time of low voltage application. Consequently, the wavelength dependency of transmissivity is reduced and color deviation is decreased. |
