title: Geometrical optics approach to the nematic liquid crystal grating: leading term formulas.
abstract: Leading term approximative analytical formulas are derived for the powers of the fringes formed by a periodically distorted homogeneous nematic layer, illuminated by a monochromatic light beam at normal incidence. The agreement between the predictions of the derived formulas and those of the direct numerical computation for the odd-order fringes is restricted to very small distortions and, thus, to very low fringe power values. On the other hand, the respective comparison for the even-order fringes gives quite satisfactory results provided the sample is sufficiently thick and the order of the fringe is low.
authors.forename: H M
authors.initials: HM
authors.lastname: Zenginoglou
authors.forename: J A
authors.initials: JA
authors.lastname: Kosmopoulos