This paper deals with the mode I crack problem of a cracked rubber sheet under shifting method of automated fringe analysis, the displacement fields in the Cartesian coordinate system are given. By the coordinate-transform equation, the radial and circular displacement distributions in the polar coordinate system are obtained. The displacement isoline distributions and displacement vector distributions near the crack tip are discussed. The strain isoline distributions near the crack tip are also analyzed in this paper. Finally, the distribution rules for the mechanical fields near the crack tip are discussed with the sector division method.