Patent ID: 7133225

Claim:
A method of manufacturing an optical system, the method comprising assembling a first unit of an optical element and a mounting frame by: disposing the mounting frame on a rotary table, wherein the rotary table is rotatable about an axis of rotation, and wherein the mounting frame has a body portion having a predefined first axis of symmetry; adjusting a position of the mounting frame relative to the rotary table such that the first axis of symmetry of the body portion of the mounting frame is substantially parallel to the axis of rotation of the rotary table; placing the optical element on the mounting frame such that supporting portions of the mounting frame are in contact with the optical element, the optical element having a first main optical surface and a predefined second axis of symmetry; rotating the rotary table into plural different rotational positions about the axis of rotation and performing at least one interferometric measurement of the first main optical surface at each of the plural rotational positions; adjusting a position of the optical element relative to the mounting frame such that the second axis of symmetry of the optical element is substantially parallel to the axis of rotation of the rotary table, wherein the adjusting is performed in dependence on a result of the plural interferometric measurements; and fixing the position of the optical element relative to the mounting frame.