Periodically deformed liquid crystal profiles are commonly encountered eith
er spontaneously under the influence of an external excitation, or intentio
nally, with the introduction of relief type gratings on the supporting surf
aces. These types of periodicity are often characterized by a pitch around
one micron or less. As the pitch is directly comparable to the optical wave
length, it is necessary to develop rigorous numerical methods to predict li
ght wave propagation within such structures. A wide angle periodic beam pro
pagation method (BPM) is proposed for the simulation of light propagation i
n purely bend/splay periodic director deformations. A common occurrence of
this type of deformation is encountered in smectic A materials under the He
lfrich effect. More importantly, bistable nematic cells with zenithal defor
mation have been developed for interesting display applications. Both afore
mentioned deformations are examined to verify the applicability of the prop
osed periodic BPM.