A device includes a projection and camera system to create an augmented reality environment in which images are projected onto a scene and user movement within the scene is captured. The projection and camera system have a camera to image scattered light from the environment and determine depth of objects in the environment. The system also has a projector to project the images onto the scene. The projection images and captured environment images share a common optical path through the same lens. The system includes an image noise cancelation system to cancel, remove, or otherwise reduce unwanted image noise caused by internal reflection of the projection images from the environment images.