Patent ID: 8509269

Claim:
A method of producing a cylindrical optical component of quartz glass that has an inner zone extending in the direction of a longitudinal axis and of an inner zone glass, wherein said inner zone is clad by a cladding zone of a cladding zone glass, the cladding zone having a mean wall thickness varies over at least part of a length thereof in the direction of the longitudinal axis of the component, said method comprising: (a) providing a first preform of the inner zone glass, the first preform comprising a contact area shaped in the form of an external cone on a face side thereof; (b) providing a second preform of the cladding zone glass; (c) embedding the contact area shaped in the form of an external cone in the cladding zone glass and welding the contact area to the cladding zone glass so as to form a composite preform that, in the contact area, comprises a conical inner-zone area of the inner zone glass that is surrounded by a cladding zone area with an internal cone shape; and (d) elongating the composite preform so as to obtain the optical component or a pre-product of the component.