| 摘要 |
<p>A rear-type projection board apparatus (rear-surface projection-type video display apparatus), of new structure, having no necessity of a housing, being superior in portability, cheaply producible, comprises a transmission-type screen 130, being disposed within an interior space, under a condition of exposing both surfaces thereof in the space, and for transmitting a visual light projected onto a rear surface therethrough, so as to display it on a video display surface on a front surface, and a video projection apparatus (projector) 102, being disposed at a predetermined position on a rear surface side of the transmission-type screen, and for projecting the visual light from a rear surface of the transmission-type screen, enlargedly, wherein the transmission-type screen has a Fresnel lens 166 (136) having Fresnel lens surfaces, covering over an entire light receiving surface for receiving the visual light, which is enlargedly projected from the video projection apparatus, whereby guiding the visual light received from the video projection apparatus into a direction perpendicular to the video display surface, while guiding external lights within the interior space downwards.</p> |
