  Structural study on the photo-switching system Pr{0.55}(Ca{1-y}Sr
y){0.45}MnO3 thin films on perovskite (011) substrate has been made with
synchrotron radiation diffraction experiment. The insulating phase of y=0.20
sample was found to be an antiferro-orbital ordered phase with large lattice
distortion and the ferromagnetic metallic phase of y=0.40 film show no distinct
lattice distortion from the paramagnetic phase, which are very similar with
(Nd,Pr)0.5Sr0.5MnO3 films. A striking contrast of the orbital ordered phase of
y=0.20 film to (Nd,Pr)0.5Sr0.5MnO3 films was its untwinned structure.
