| 摘要 |
A planetarium projector and the method of making the projector is described wherein a light source is surrounded by an opaque enclosure having transparent spots or lines. The enclosure is fabricated from originally planar sheets of photographic film. The enclosure is preferably cylindrical however it may assume other shapes such as conical or a rectangular parallelepiped. The planar sheets of negative type of photographic film are patterned by exposure through a master transparent sheet of plastic on which star locations, zone plate lens, or lines representing geographical boundaries or other figures are drawn in opaque ink.
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