Disclosed are an apparatus and a method for detecting deformation of a structured light depth imaging system and automatic re-calibration for the depth imaging system. In one embodiment, a depth imaging device includes a light projector, a camera and a processor. The light projector emits light corresponding to a projected pattern image having a plurality of features with known locations in the projected pattern image. The camera captures the light reflected by an environment of the depth imaging device and generates a reflected pattern image as a two-dimensional (2D) projection of the environment. The reflected pattern image includes a plurality of features that correspond to the features of the projected pattern image. The processor detects a misalignment for a distance or an orientation between the light projector and the camera based on a relationship between the features in the projected pattern image and the features in the reflected pattern image.