Operating knob for an optical system

摘要

An operating knob ( 20 ) for an optical system ( 100 ) is disclosed. The operating knob ( 20 ) has a first and a second coaxially arranged rotating element ( 21, 22 ). The first and the second rotating element ( 21, 22 ) have at least partly conical form. The first rotating element ( 21 ) has at the side directly opposing the second rotating element ( 22 ) a larger diameter than the second rotating element ( 22 ) and a step is formed at the side of the second rotating element ( 22 ) directly opposing the first rotating element ( 21 ), wherein the step possesses a diameter which is approximately the diameter of the first rotating element.