Langmuir-Blodgett (LB) films composed of the mixture of an amphiphilic polymer containing azobenzene (Az) side chain (6Az10-PVA) and 4'-pentyl-4-cyanobiphenyl (5CB) were prepared to mimic the two-dimensional contacting region of the LC/Az interface of the command surface which photochemically switches the LC alignment. UV-visible absorption and Fourier transform infrared spectroscopic measurements were carried out under illumination. These procedures allowed separate and simultaneous evaluations of the static state and dynamic molecular motions of both Az and LC molecules, which probably reflect the initial triggering step of the "domino-mode" response of LC. The spectroscopic data indicated the induction of reversible perpendicular/tilt orientational changes of both the Az side chain and 5CB molecule upon alternative irradiation of 365 and 436 nm light. Thus, 6Az10-PVA/5CB hybrid LB film can be regarded as a satisfactory interface model of a command surface that promotes the homeotropic/planer alignment switching, From the time courses of the photoisomerization of Az and the orientational change, it was clearly shown that the molecular tilt is not governed only by the trans/cis ratio of Az unit, but is strongly process-dependent (forward or back process), indicative of involvement of strong molecular cooperativity. The validity and limitation of the LC research using this model system are also discussed.