A projection device and an information processing method are described. The projecting device includes a display image generation unit for generating a plurality of frames of the continuous images to be displayed; a light source unit for receiving the plurality of frames of the continuous images to be displayed generated by the display image generation unit and forming a corresponding set of the light rays sequentially; a light path transformation unit having N kinds of optical states, N is the natural number greater than 1; a projecting unit for projecting the light rays inputted to it to the first to Nth projection regions; and a control unit for controlling the light source unit so that the images to be displayed are switched in a predetermined frequency, and for controlling the light path transformation unit so that the N kinds of optical states are switched in the predetermined frequency.