Field induced deformations of the bookshelf geometry in electroclinic liquid crystals are investigated by means of spatially resolved phase retardation experiments. It is found that the triangular deformation model does not adequately describe the optical data, and underestimates the achievable device contrast ratios. To more correctly model the smectic layer deformation, it is necessary to consider a distribution of molecular directors within a stripe domain. ©1997 American Institute of Physics.