EP2804839

• Heraeus Quarzglas GmbH & Co. KGsince Oct 24, 2014; EPO record ends Feb 24, 2017

A quartz glass tube as a semi-finished product for an optical component that has an inner bore extending along a tube centre axis for the acceptance of a core rod and a tube wall limited by an inner casing surface and an outer casing surface is already known; within said tube wall an inner region made of a first quartz glass and an outer region made of a second quartz glass surrounding the inner region contact one another at a contact surface which runs around the centre axis, the first quartz glass and second quartz glass having different indices of refraction. In order to provide a quartz glass on this basis that facilitates the production of optical components for special applications such as laser-activated optical components in wand or fibre form, the invention states that the contact surface has a non-round course in the radial cross-section and the inner casing surface has a circular course.

From the international application WO2013107787