Abstract: A projector 3 is provided for casting light toward the inside of a spherical screen 2. A first reflecting mirror 4 is arranged inside the spherical screen 2 on the optical axis 15 of the projector 3, and a second reflecting mirror 5 of a convex mirror on the optical axis 15 is arranged adjacent to a body tube 16 of the projector 3. The light emitted from the projector 3 is cast onto the entire surface of the spherical screen 2 via the first and second reflecting mirrors 4, 5. Images with virtual presence can be projected onto the entire surface of the spherical screen by the simple structures using the single projector.