Abstract: A display device includes a projector and a translucent hemispherical screen disposed in a black box, with the axis of the hemisphere extending perpendicular to a surface on which an image from the projector is cast. A semitransparent mirror is disposed on the opposite side of the image-receiving surface of the hemispherical screen, aslant to the axis of the hemisphere and opposite a viewer. The image of an spherical object projected on the hemispherical screen can be seen in stereoscopic spatial vision. The image viewed through the semitransparent mirror appears as if it was floating in space.

Abstract: A light for an infrared ray) emitting member or a reflective (or an infrared ray reflective) medium is mounted at a predetermined position on an object upon which an image is projected. The light emitting member or the reflective medium is acquired in the coaxial direction of an image projecting unit by an (infrared ray) image pick-up means and video signals obtained by the (infrared ray) image pick-up means are digitized in an image processing unit, such that a highly luminous point of the light emitting or reflected portion occurs in a binary image. A central value of a primary moment on the binary image including the high luminous point, is calculated in real time, and the calculated data is fed back to an electrically-driven driving portion of the image projecting unit, so that the image may be continually projected at the predetermined position. The electrically-drive turntable automatically controls the image projecting direction including the direction of light.