(under subclass 738) Subject matter in which the light-controlling means is in the form of an opaque screen having a variable aperture therein, such screen being disposed in the path of the light beam passing through the lens in such a position axially of the lens to either restrict the amount of light that reaches the lens or restrict the amount of light transmitted by the lens.
(1) Note. The subject matter under this definition includes opaque screens in which the aperture is of annular shape and located either within the screen or at the periphery thereof.
(2) Note. Mere recitation of a diaphragm is inadequate for classification here. This subclass and subclass 740 are limited to special shapes or locations of diaphragms.
SEE OR SEARCH CLASS
353, Optics: Image Projectors,
75, and 97 for an image projector having a diaphragm.
396, Photography, 505+, for camera diaphragms, and see (2) Note above.
