Projector for transparencies, producing stimulating image in mid air, includes beam-splitting- and concave Fresnel mirrors

摘要

The projector comprises a holder for a projection slide (22) in the lamp (14) beam. After the slide, a beam-splitting mirror is acutely-angled with respect to the beam, reflecting an image to the observer. A Fresnel concave mirror (36) is located behind the beam-splitting mirror, in the projected beam path, and transverse to its propagation. The slide is surrounded by mirrors (16-20). The space they enclose widens after the slide, in a pyramidal-or funnel shape.