Inside helmet sight display apparatus

Abstract

Helmet mounted display apparatus in which a reflective inside surface of a partially transparent visor is used as the primary optical element. A paraboloidal inside visor surface coated with a metallic film may be used. A light source image or a virtual image is positioned at the focal point of the inside surface of the visor. The outside surface of the visor may be coated with an anti-reflective coating.

I claim: .[.1. A head-mounted display system comprising: 
     
        appears to come from said focal point..]. .[.2.  The apparatus as defined by claim 1 and means for mounting said visor in a fixed geometrical relationship to an observer's head, so that said visor may move in consonance with the observer's head movements..]. .[.3. The apparatus of claim 2 wherein said surface is defined by a paraboloid of revolution..]. .[.4. The apparatus of claim 2 wherein the light emitting means includes a light source centered at said focal point..]. .[.5. The apparatus of claim 2 wherein the light emitting means includes a light source and a mirror configured so that the virtual image of the source is centered at said focal point..]. .[.6. Visual display apparatus, which comprises: a. a visor having an inner concave parabolic surface which is partially reflective and partially transparent, said visor being of sufficient size to shield the eyes and forehead of an observer;   b. a helmet to which the visor is mounted in such a manner that an observer wearing the helmet may have his eyes shielded by said visor; and   c. light emitting means, fastened to the concave visor surface, for projecting an image which is centered at the focal point of the concave visor surface..]. .[.7. The apparatus of claim 5 wherein said light emitting means includes a light source and a substantially planar mirror placed at a predetermind angle to said light source..]. .[.8. The apparatus of claim 2 wherein the visor has a substantially spherical curvature..]. .Iadd. 9. A head-mounted display system comprising:   a. a partially transparent, partially reflective visor, one surface of said visor having a curvature for collimating light, the curvature having a definable focal point;   b. light emitting means position so that light travels from said means to a reflective surface which is located out of the observer's normal forward line of sight, the light being reflected from the reflective surface directly, and without being further reflected, to the one surface of the visor where the light is collimated and at least partially reflected to the observer generally along the observer's normal forward line of sight, the observer thus receiving the light as if it were originating at infinity. .Iaddend..Iadd. 10. The apparatus of claim 1 wherein said light emitting means is centered at said focal point. .Iaddend.