Optical Material Processing

Prof. Dr. Joly, 5 ECTS

This module naturally follows the “Basics of Lasers” module and aims at deepen the knowledge on a few specific aspects of lasers. In particular we will study the Z-cavity of one of the most popular laser system: the Titanium: sapphire laser. The purpose here is to show why simpler cavity is not possible. It requires understanding properly the concept of stability of laser cavity and introduces the problem of astigmatism. In a second stage we see how dispersion effects can hamper the properties of a mode-locked laser system and see how to circumvent this. We then study the different method used to characterize ultrashort laser pulse. This starts from basics concepts of autocorrelation but review more advanced techniques allowing to retrieve fully the amplitude and phase of a laser pulse. Towards the end of the lecture several topics are possible and it will be chosen together with the students. This can be for instance (i) the polarization and the Jones’ formalism (ii) the Maxwell-Bloch equations (iii) the origin of spontaneous emission. Finally in order to broaden the contents of the lecture the students are asked to prepare one half-an-hour presentation of the topics of their choice. The topics are discussed during the first two sessions of the lecture and must focus on a physical aspect of laser.

PD Dr. Erdmann, 5 ECTS

Semiconductor lithography covers the process of pattern transfer from a mask/layout to a photosensitive layer on the surface of a wafer. It is one of the most critical steps in the fabrication of microelectronic circuits. The majority of semi-conductor chips are fabricated by optical projection lithogra-phy. Other lithographic techniques are used to fabricate litho-graphic masks or new optical and mechanical devices on the micro- or nanometer scale. Innovations such as the introduc-tion of optical proximity correction OPC), phase shift masks (PSM), special illumination techniques, chemical amplified resist (CAR) materials, immersion techniques have pushed the smallest feature sizes, which are produced by optical pro-jection techniques, from several wavelengths in the early 80ties to less than a quarter of a wavelength nowadays. This course reviews different types of optical lithographies and compares them to other methods. The advantages, disad-vantages, and limitations of lithographic methods are dis-cussed from different perspectives. Important components of lithographic systems, such as masks, projection systems, and photoresist will be described in detail. Physical and chemical effects such as the light diffraction from small features on ad-vanced photomasks, image formation in high numerical aper-ture systems, and coupled kinetic/diffusion processes in mod-ern chemical amplified resists will be analysed. The course includes an in-depth introduction to lithography simulation which is used to devise and optimize modern lithographic processes.

Dr. Klämpfl, 5 ECTS

• Repetition of important topics of optics
• Scattering of light
• Basics of laser tissue interaction
• Diagnostics applications of Light and lasers
• Therapeutics applications of light and lasers
• Theoretical and practical exercises

Prof. Dr. Hoffmann, 2 x 2.5 ECTS

(These are two 2.5 which can be studied indepently, although it is recommended to combine them. It is the only regularly offered module which is offered in German. )

Lasersystemtechnik 1 (Wintersemester)

• Einführung: Weltmarkt für Lasersysteme, Strahlquellen und deren Anwendung in der Materialbearbeitung
• Grundlagen zur Ausbreitung und Fokussierung von Laserstrahlung
• CO2-Laseranlagen: Strahlerzeugung, Bauformen für Strahlquellen, Strahlführung und –formung, Anlagenbeispiele, Anwendungen
• Festkörper-Laseranlagen: Strahlerzeugung, Bauformen, Strahlführung über Lichtleitkabel, Strahlformung, Anlagenbeispiele, Anwendungen
• Hochleistungdioden-Laseranlagen: Strahlerzeugung, Strahlführung und –formung, Anlagenbeispiele, Anwendungen
• Neuere Entwicklungen bei Strahlquellen und Laseranlage
• Introduction: Global Market for Laser Systems, Beam Sources and their application in material processing
• Fundamentals of Propagation and Focussing of laser radiation
• CO2-Laser Systems: Beam Generation, design of beam sources, beam guidance and –shaping, examples of systems, Applications
• Solid-State-Laser Systems: Beam Generation, design, beam guidance via light conducting cable, beam shaping, examples of systems, Applications
• High-Power-Diode-Laser Systems: Beam Generation, beam guidance and shaping, examples of systems, Applications
• Novel developments in beam sources and Laser Systems

Lasersystemtechnik 2 (Summersemester)

•  Programmierung von Laseranlagen, Führungsverhalten
• Erzeugung von Verfahrbefehlen und deren Umsetzung in eine Vorschubbewegung
• Kommunikationstechniken für die Steuerung und Automatisierung von Laseranlagen
• Neuere Entwicklungen für „Laserroboter“
• Spanntechnik für das Laserstrahlschneiden
• Spanntechnik für das Laserstrahlfügen
• Sicherheit von Laseranlagen

Prof. Dr. Pflaum, Dr. Hohmann, 2.5 ECTS

Content
• Introduction to physical phenomena used in development of modern solid state lasers
• Practical approaches used in design of solid state lasers
• Introduction to modeling and simulation of the lasing process
• Modeling of basic solid state laser performance using a commercial software package
• Practical familiarization with various optical, opto-mechnical, and opto-electrical components used in solid state laser

The students gain the following competences:
• Setting up basic modeling of a solid state laser using ASLD software
• Be able to apply modeling for evaluation of performance of a basic laser system
• Apply basic optimization of the laser system model
• Identification of an appropriate laser system for a given application
• Performing basic characterization of laser beam output parameters
• Enhanced understanding of the laser physics
• Familiarization with modern design approaches used in solid state laser engineering
• Improved understanding of linear and nonlinear effects relevant for linear and nonlinear laser beam propagation

Dr. Cvecek, 5 ECTS

• Physical phenomena applicable in Laser Technology: EM waves, Beam Propagation, Beam Interaction with matter
• Fundamentals of Laser Technology: Principals of laser radiation, types and theoretical understanding of various types of lasers
• Laser Safety and common applications: Metrology, Laser cutting, Laser welding, Surface treatment, Additive Manufacturing
• Introduction to ultra-fast laser technologies
• Numerical exercises related to above mentioned topics
• Demonstration of laser applications at Institute of Photonic Technologies (LPT) and Bavarian Laser Centre (blz GmbH)
• Possible Industrial visit (e.g. Trumpf GmbH, Stuttgart)
• Optional: invited lecture about a novel laser application

Course is taught in German or English; check in the first session

Dr. Müller, 5 ECTS

• Stereo-Imaging
• Scannen dreidimensionaler Objekte
• Computer-Tomographie und verwandte Techniken
• 2D Darstellung dreidimensionaler Datensätze
• 3D Bildverarbeitung
• 3D Druck-Verfahren
• 3D Projektion und Darstellung
• Darstellung wissenschaftlicher Daten mittels “Virtueller Realität” (VR)