The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 01, 2008
Filed:
Feb. 22, 2005
Lars Ortmann, Jena, DE;
Joerg Kandler, Cospeda, DE;
Andreas Menzel, Jena, DE;
Matthias Mueller, Jena, DE;
Lutz Parthier, Klein-Machnow, DE;
Gordon Von Der Goenna, Jena, DE;
Lars Ortmann, Jena, DE;
Joerg Kandler, Cospeda, DE;
Andreas Menzel, Jena, DE;
Matthias Mueller, Jena, DE;
Lutz Parthier, Klein-Machnow, DE;
Gordon Von der Goenna, Jena, DE;
Schott AG, Mainz, DE;
Abstract
The method provides CaFsingle crystals with low scattering, small refractive index differences and few small angle grain boundaries, which can be tempered at elevated temperatures. In the method a CaFstarting material is heat-treated for at least five hours at temperatures between 1000° C. and 1250° C. and then sublimed at a sublimation temperature of at least 1100° C. in a vacuum of at most 5*10mbar to form a vapor. The vapor is condensed at a condensation temperature of at least 500° C., which is at least 20° C. below the sublimitation temperature, to form a condensate. Then a melt formed from the condensate is cooled in a controlled manner to obtain the single crystal, which is subsequently tempered. The method is preferably performed with a CaFstarting material including waste material and cuttings from previously used melts.