Adjusting device for lenses

Claim 1

An adjusting device for a lens system having at least two optical elements displaceable parallel to the optical axis, wherein the displacement paths of the optical elements are subject to interdependent but different courses of movement, comprising: a first optical element; a second optical element arranged along a common optical axis with said first optical element; a rotatable adjusting ring surrounding said optical elements and being movable parallel to said optical axis, for focusing the lens system, wherein rotation of said adjusting ring displaces the ring along said optical axis; a tubular member positioned within said adjusting ring, said tubular member comprising near one end a mount for said first optical element and including near its opposite end a guide groove in its wall, wherein said adjusting ring is rotatable with respect to the tubular member, wherein the adjusting ring and the tubular member define a fixed relative position along the optical axis, and wherein the tubular member is displaced only axially; a hollow cylindrical member displaceably mounted within said tubular member, said cylindrical member comprising a mount for said second optical element; a guide element mounted on the external surface of said cylindrical member for engagement with said guide groove and for guiding the cylindrical member in both an axial and a radial displacement; and means for drivingly connecting said adjusting ring with said cylindrical member.