Dynamic response of molecular reorientation near the alignment surface of bistable cholesteric liquid crystal devices was observed by means of the total reflection ellipsometry. From the experimental results, the deviation from the original switching voltage to which the image sticking problem has a close relationship was confirmed, and the cause of the image sticking problem was considered from the viewpoint of the surface energy and Helfrich-type modulation. Especially when the surface free energy is low, director near the alignment surface seems to be distorted by disclinations and Helfrich-type modulation.