Method for production of an optical component made from quartz glass

A method for producing an optical component of quartz glass, said method comprising:

• producing a hollow cylinder having a length from a raw cylinder of quartz glass as starting material, said raw cylinder having a length greater than the length of the hollow cylinder, said producing including the steps of
• a. mechanically machining the raw cylinder so that the raw cylinder has an inner bore therein that has been machined to a final dimension;
• b. heating the raw cylinder bore in a collapsing zone so as to partially collapse a portion of the raw cylinder and inner bore thereof in said collapsing zone, said collapsing zone being spaced at a distance from an end of the raw cylinder, said distance being at least the length of the hollow cylinder;
• and
• c. separating the hollow cylinder in the region of the collapsing zone from a remaining portion of the raw cylinder so that the hollow cylinder has a first end with a constriction therein comprising at least part of the collapsed portion of the raw cylinder;
• forming a coaxial arrangement with said hollow cylinder wherein a core rod of quartz glass is supported coaxially in the hollow cylinder, with the core rod having an end supported in the constriction in the first end of the hollow cylinder;
• and
• elongating the coaxial arrangement, including
• supplying the coaxial arrangement in vertical orientation to a heating zone and
• softening the coaxial arrangement therein zonewise, starting with a lower end thereof, and
• drawing off the optical component downward from a softened region of the coaxial arrangement.