Patents Examined by Michael T Piery
  • Patent number: 7540983
    Abstract: In the case of a method of producing aspherical optical surfaces of optical elements (1), in particular for use in microlithography for producing semiconductor elements, the optical element (1) is ground for example in the form of a meniscus. In a first method step, the optical element (1) is introduced into a basic form (2), which has a spherical form bed and is being held at a distance over the form bed (3). After that, an intermediate medium (6) is introduced in the basic form (2) between the optical element (1) and the form bed (3) and, subsequently the optical element (1) being removed together with the intermediate medium (6) from the basic form. Then, the spherical form bed (3) of the basic form (2) or a second basic form is transformed into an aspherical form bed (3?) computationally determined in advance.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: June 2, 2009
    Assignee: Carl Zeiss SMT AG
    Inventors: Ernst-Dieter Knohl, Andreas Frommeyer, Hermann Schubert