Director Gratings and Light Diffraction in the Nematic Cells with Spatially Modulated Easy Axis

Periodic spatial modulation of easy axis with period 2/Q onto the cell surfaces leads to the appearance of the director grating with the same period in the LC bulk. Incident light wave intensity modulated with period 2/q induces additional director gratings in the cell bulk with periods 2/q, 2/(Q + q), 2/(Q - q). Diffraction of a probe light beam on such gratings is investigated for both planar and nearly homeotropic geometry of the director distribution and for strong and weak anchoring of director on the cell surfaces.