The ocular fundus of an eye under examination is stereo-photographed via an ocular fundus photographing optical system with a predetermined parallax (S100). The photographed stereo ocular fundus images are subjected to color separation (S101) when a process of measuring the three-dimensional shape of the ocular fundus of the eye under examination is to be performed using left and right parallax images obtained. A depth information measurement process to derive depth information of a specific ocular fundus region is carried out on the respective stereo ocular fundus images of different wavelengths obtained by the color separation (S103), and a thickness information measurement process is carried out to derive, as thickness information for specific ocular fundus tissue, a difference of depth information obtained respectively from stereo ocular fundus images of different wavelength components in the depth information measurement process (S104). Additionally, a spatial frequency filtering process is carried out for an image of a specific frequency component (S103).
