| 摘要 |
<p>ROTARY SCREEN FOR RECEIVING OPTICAL IMAGES, PARTICULARLY ADVERTISING IMAGES. The rotary screen is mounted in the median area of a spherical volume, the rear face of which being made opaque except in its central portion, while its front face is perfectly transparent, a projector being placed rearwardly the above mentioned volume in central axis of the portion which is not opaque in order to enable light rays from the projector to pass through the above mentioned volume to reach the rotary screen.</p> |
