| Popis: |
Optical and electro-optical characteristics of a positive dichroic dye-doped Twisted Nematic Liquid Crystal Layer (TNLCL) for two different orientations of the input light polarization to the NLC director α (α = 0°, α = 90°) and various NLC optical path lengths A = Δnd/λ (Δn = real part of birefringence, d = cell thickness, λ = wavelength) are investigated. In the case of one polarizer, the maximum contrast ratio is obtained for A ≳ 1.2 (α = 0°) and A ∼ 0 (α = 90°), regardless of whether Δn or d is changed. The viewing characteristics of a dye doped TNLCL with one polarizer are shown to be more uniform than those for a “pure” TNLCL between parallel polarizers. |
