Lens hood (lens shade), having a variable angular field and being format-related, for sliding variable-focus lenses, having synchronous wing adjustment corresponding to the focal length

摘要

To obtain a lens hood which fits precisely for each desired and possible angular field of a variable-focus lens it is necessary to correspond to the angular field of the respectively used focal length in that the four wings of the lens hood assume a fitting angular position in that they are suspended on a telescope-like linkage, the possibility of movement is produced with the aid of hinges, and this linkage is correspondingly controlled by a pin which engages in a guiding curve (leading curve) accommodated in a carrier, which then leads to the respectively desired angular position of the wings. This can also be achieved by means of an electric motor, without carriers, pins and guiding curve.