Bistability of the surface stabilized ferroelectric liquid crystal (SSFLC) is one of the most important factors of display performances. The electrooptical switching is based on the bistability which provides threshold characteristics to the SSFLC display device. The threshold properties of the SSFLC device which has a layer structure of liquid crystal molecules and provides an in-plane molecular switching are assumed to be governed by not only a sur face anchoring but also a bulk structure itself. We show some experimental results which suggest a contribution of ferroelectric liquid crystal’s bulk structure to the electrooptical threshold properties. Layer structures : the bookshelf and the chevron geometries are one of the main bulk factors. Our experimental results clarified that the polarization switching behavior was intrinsically different between the bookshelf and the chevron structures. The bookshelf geometry also shows a possibility of gray shades.