Abstract
The mean square tilt angle of a nematic slab with finite anchoring energy and periodic boundary conditions has been theoretically investigated, as a function of the slab geometry and of the reduced extrapolation length. If the anchoring strength is free-surfacelike, the contrast is affected by a loss ≳10% at room temperature if the ratio between the anchoring pitch and the cell thickness is ≳0.5.
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Abbreviations
- λ :
-
anchoring pitch
- h :
-
cell thickness
- Λ :
-
λ/h
- (ξ = x/λ, η = y/h):
-
reduced coordinates
- ϑ(ξ, η) :
-
local tilt angle
- κ :
-
elastic constant
- wa :
-
anchoring energy anisotropy
- b=κ/w a :
-
de Gennes-Kleman extrapolation length
- B=b/h :
-
reduced extrapolation length
- T NI :
-
nematic-isotropic transition temperature
- τ:=(T/T NI ) − 1:
-
reduced temperature
- Φ :
-
easy axis direction
- α :
-
Φ MAX
- 〈ϑ 2± 〉:
-
mean square tilt angle along the boundary
- α∥(α⊥):
-
absorbance coefficients of the p-dye
- r :
-
α∥/α⊥: dichroic ratio
- c :
-
contrast
- G :
-
contrast gain
- S :
-
order parameter
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Barbero, G., Strigazzi, A. The contrast gain in a guest-host nematic display due to a periodic boundary condition. Appl. Phys. A 31, 55–57 (1983). https://doi.org/10.1007/BF00617189
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DOI: https://doi.org/10.1007/BF00617189