A processing method for depositing porous silica and doped silica films is provided. More particularly, the upper surface of the rail seal is formed with a recessed portion or flangeway for receiving the flanged-end of a train. Different inserts can be stacked on one other. Each liquid crystal optical element may be made from one or more suitable liquid crystal materials that can be controlled electronically to vary the effective index of refraction of one or more different regions of the liquid crystal optical element, thereby steering incoming light towards a particular one of two or more scattering regions of an associated scattering module.