A Full-Color Direct-View TFT-LCD with a Polymer-Dispersed Structure.

We propose a direct-view TFT-LCD with a wide viewing-angle which uses a polymer-dispersed liquid-crystal panel and a pair of polarizers. We call this device a polymer-dispersed LCD with crossed Nicols (PDN). The PDN allows panels to be made with low scattering levels.This suggests the use of fluorinated liquid crystals (F-LC) that show a high voltage-holding ratio in TN-LCDs. We found that F-LCs show good solubility with resins having low solubility parameters. A voltage-holding ratio of over 98% is shown, which is almost equal to the value for TN-LCD. The vertical viewing range exceeds ±60°, with a contrast ratio of over 5 and no image reversal. The range is almost three times the TN-LCD value. Molecular alignment is symmetrical and the variation of overall retardation is suppressed. The TFT-LCDs fabricated show a high contrast ratio and no imag reversal at any viewing angle.