Abstract: The invention relates to a method of joining substrates. It is the object of the invention in this respect to join substrates of substrate materials together without having to exert an increased effort for a coating with additional coating processes to be carried out and to be able to achieve a good quality of the join connection in so doing. In the method in accordance with the invention a pretreatment of at least one join surface of a substrate to be joined is carried out in low pressure oxygen plasma prior to the actual joining. On the joining, a contact force acts on the substrates to be joined in the range 2 kPa to 5 MPa and in this process a heat treatment is carried out at an elevated temperature of at least 100° C. and at under pressure conditions of a maximum of 10 mbar, preferably <10?3 mbar.
Type:
Application
Filed:
February 21, 2012
Publication date:
March 27, 2014
Applicants:
Friedrich-Schiller-Universität Jena, FRAUNHOFER-GESELLSCHAFT zur Förderung der angewandten Forschung e.V.
Inventors:
Gerhard Kalkowski, Carolin Rothhardt, Mathias Rohde, Ramona Eberhardt
Abstract: The invention relates to a Q-switched laser comprised of a pump light source (1), an optical resonator accommodating a laser medium (6), and a passive Q-switch (5). It is the object of the present invention to provide an improved Q-switched laser which is of a simple and compact setup while having the least possible jitter of the repetition time. To achieve this target, the invention proposes that by means of a beam splitter (8) part of the light coupled out of the optical resonator is passed on to an optical delay line (9) and coupled back into the optical resonator upon having passed through the optical delay line (9).
Type:
Grant
Filed:
September 17, 2010
Date of Patent:
January 7, 2014
Assignees:
Fraunhofer-Gesellschaft zur Forderung der Angewandten Forschung E.V., Friedrich-Schiller-Universitat Jena
Inventors:
Andreas Tünnermann, Dirk Nodop, Alexander Steinmetz, Jens Limpert
Abstract: The invention relates to a method for producing an optical assembly, comprising at least two optical functional surfaces arranged in a fixed positional relationship to one another on a common supporting structure, wherein by means of a processing machine, in various process steps, at least two optical functional surfaces and at least one reference structure having a defined and measurable relative position to the optical functional surfaces are produced. The supporting structure remains rigidly connected to the processing machine until said process steps have been completed, and wherein the optical functional surfaces are then measured relative to the at least one reference structure, and any deviation from a target shape and target position is determined, after which said process steps are repeated at least once with modified actuation of the processing machine. The invention further relates to an optical device comprising an optical assembly produced in this way and to a unit for carrying out such a method.
Type:
Application
Filed:
September 13, 2010
Publication date:
September 20, 2012
Applicant:
Friedrich-Schiller-Universitat Jena
Inventors:
Sebastian Scheiding, Stefan Risse, Andreas Gebhardt, Christoph Damm, Thomas Peschel, Ralf Steinkopf
Abstract: New thieno[3,4-b]pyrazine copolymers are prepared by reacting 5,7-functionalized thieno[3,4-b]pyrazines with substituted aromatics in the presence of solvents, bases and polymerization catalysts, the copolymers thus prepared being employed preferably in the production of photovoltaic cells.
Type:
Grant
Filed:
March 22, 2007
Date of Patent:
July 10, 2012
Assignees:
Thüringisches Institut für Textil-und Kunststoff-Forschung E.V., Friedrich Schiller Universität Jena
Inventors:
Steffi Sensfuss, Maher Al Ibrahim, Lars Blankenburg, Elisabeth Klemm, Raja Shahid Ashraf, Munazza Shahid
Abstract: The invention relates to an optical fiber as an optical waveguide for the single-mode operation. The present invention proposes a fiber having a microstructure, by which the propagation of modes of a higher order are selectively suppressed in the optical waveguide. At the same time, the propagation of transversal modes of a higher order is dampened more strongly than the propagation of the fundamental modes of the optical waveguide.
Type:
Application
Filed:
March 12, 2010
Publication date:
March 22, 2012
Applicants:
FRIEDRICH-SCHILLER-UNIVERSITÄT JENA, FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.
Abstract: The invention relates to a method for cleaving cervimycin esters. An object of the invention to convert in a simple manner the cervimycin esters which are less active but formed in larger quantity into the highly active cervimycin K that occurs as a minor component in the preparation by fermentation, is achieved by preparing unesterified cervimycins from cervimycin esters with di- or monomethylated malonic acids, by ester cleavage effected by at least one esterolytic enzyme at temperatures of 20° C. to 75° C. and a pH of pH 5.0 to 10.0, preferably pH 6.0 to 9.0.
Type:
Application
Filed:
September 25, 2006
Publication date:
June 4, 2009
Applicants:
LEIBNIZ-INSTITUT FÜR NATURSTOFF-FORSCHUNG UND INFE, FRIEDRICH-SCHILLER-UNIVERSITÄT JENA
Abstract: A method and apparatus for determining fluorophores on objects, especially on the living ocular fundus, which makes it possible to reliably distinguish at least partially overlapping fluorophores of objects in excitation and/or fluorescence spectra even if fluorescence intensities are very low and to select them for analysis, and optionally create a two-dimensional representation. The object (4), e.g., the ocular fundus for ophthalmological examinations, is illuminated point to point with a pulsed laser (1) and excited to autofluorescence with two-dimensional extension. The transient fluorescence light created after excitation by each laser pulse is detected in time-correlated individual photon counting (11). From the time behavior of the fluorescence light determined by individual photon counting for each site of autofluorescence, the fluorescence decay time constants are calculated, and conclusions are drawn therefrom regarding the excited fluorophores in the object (4).
Type:
Grant
Filed:
May 1, 2000
Date of Patent:
April 16, 2002
Assignee:
Friedrich-Schiller-Universität Jena Buero für
Furschungstransfer-Sachgebiet Schutzrechte
Inventors:
Dietrich Schweitzer, Achim Kolb, Martin Hammer, Eike Thamm