1. A video signal processing device comprising: when different partial areas in a predetermined display area are respectively a first area and a second area, a motion vector detection unit which detects, by using a first broad image corresponding to the display area of a first frame and a second broad image corresponding to the display area of a second frame, a motion vector which represents a motion between the first broad image and the second broad image; a first interpolated partial image generation unit which generates, by using a first partial image corresponding to the first area of the first frame, a second partial image corresponding to the first area of the second frame, and the motion vector, a first interpolated partial image that is inserted between the first frame and the second frame and corresponds to the first area; and a second interpolated partial image generation unit which generates, by using a third partial image corresponding to the second area of the first frame, a fourth partial image corresponding to the second area of the second frame, and the motion vector, a second interpolated partial image that is inserted between the first frame and the second frame and corresponds to the second area.