Low diffraction iris diaphragm for camera objective - has aperture further reduced below min. width by linearly varying, low density optical filters introduced over aperture

摘要

The aperture plates form the diaphragm aperture and determine its variable size. The diaphragm has a device (10-14, 31-34) for linear variation of its aperture, by which the aperture plates (21-24) can be moved from a maximum aperture to a specified small aperture not producing any diffraction. when the aperture is a minimum at least two low density filters (50, 60) with linearly varying density can be swung into the aperture formed by the aperture plates (21, 24).