(under subclass 642) Subject matter wherein the lens is capable of receiving light rays from the entire horizon simultaneously and producing from such rays a single image of the entire horizon.
(1) Note. The lens must be capable of receiving light rays from all portions of the entire horizon simultaneously. See this class, subclass 726 for lenses combined with a reflecting means for sequentially directing rays from fractional portions of the horizon through the lens, but which cannot receive rays from the entire horizon simultaneously.
SEE OR SEARCH THIS CLASS, SUBCLASS:
504, for lenses maintained in an extended spacing structure to provide a wide field of view.
749, and 754, for lenses having a particularly wide field of view, but less than the requirement of the above definition.
