Laser Physics and Technology
PDF Course Catalog Deutsche Version: LT
Version: 1 | Last Change: 19.09.2019 15:08 | Draft: 0 | Status: vom verantwortlichen Dozent freigegeben
Long name | Laser Physics and Technology |
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Approving CModule | LT_BaET, LT_BaOPT |
Responsible |
Prof. Dr. Stefan Altmeyer
Professor Fakultät IME |
Valid from | winter semester 2022/23 |
Level | Bachelor |
Semester in the year | winter semester |
Duration | Semester |
Hours in self-study | 78 |
ECTS | 5 |
Professors |
Prof. Dr. Stefan Altmeyer
Professor Fakultät IME |
Requirements | mathemtics: matrices differential calculus integral calculus physics / optics: basics of geometrical optics basics of wave optics |
Language | German |
Separate final exam | Yes |
Eichler, Eichler: Laser - Bauformen, Strahlführung, Anwendungen (Springer) |
Poprawe: Lasertechnik (Copy-Shop AC-UNI-COPY) |
Pedrotti, Pedrotti, Bausch, Schmidt: Optik für Ingenieure. Grundlagen (Springer) |
Details |
As long as the number of participants is not too high, oral examination is preferred of written exams. Lowest competence level checked is knowledge. This could be e.g. structural components that are present in every laser, the definition of physical quantities like beam quality, beam quality factor, beam parameter product, or it could be wavelenths, typical power and fields of application of the mmost important industrialy lasers. The next competence level is related to skills. Examination could be done by a beam calculation of a gaussian beam along an optical path with lenses, the calculation of the potential optical stability of a resonator, or by a rough calculation of the expected number of longitudianl modes of a laser with a given laser medium and given resonator parameters. The highest competence level adressed is methodical expertise. It can be checked by the discussion of a real world task: E.g.: What are the basic parameters required for a welding process, semiconductor lithography or an medical operation of the eye. Give sound explainaitions and describe further procedure for parametrization and choice of laser source and optical equipment. Include economical and safety considerations. In a guided discussion it can be found out easily, if the underlying principles are understood and can be applied proactively, if intellectual transfer is made and if there is sufficient overview. |
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Minimum standard | Correct answer of at least 50 % of the questions |
Exam Type | EN mündliche Prüfung, strukturierte Befragung |
Goal type | Description |
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Knowledge | Types of lasers and their fileds of application gas lasers CO2 laser excimer laser argon ion laser dye laser solid state laser diode laser optical pump telecommunication laser material processing laser principle absorption, spontaneous emission, stimulated emission Maxwell-Boltzmann distribution inversion 3- and 4 level systems rate equations transversal modes Frensel number optical regimes: geometrical optics, Fresnel diffraction and Fraunhofer diffraction diffraction operator, Eigenvalues and Eigenfunctions Lagueree-Gauss modes and Hermite-Gauss modes mathematics of Laguerre-Gauss modes transversal monomode lasers axial modes resonator and standing waves comb of modes and amplification bandwith Fabry-Perot interferometer, Etalon frequency bandwidth of an axial mode quality factor and finesse axially monomode laser temporal coherence, coherence length properties of the gaussian beam complete definiton with one single parameter: beam radius or Rayleigh length Beam quality and beam quality factor diffraction limited beam as consequence of Heisenberg's uncertainty relation propagation of gaussian beams beam transfer matrices ABCD law of beam propagation Rayleigh length as location of strongest wavefront bending types of - and reasons for - deviations of Gaussian beam propagation from geometrical optics resonator design g parameter stability of resonators as a eigenvalue problem stability diagram stability and mode volume If sufficient time in the semster left: Ultra short pulse lasers laser materials with high amplificationbandwidth dispersion compensation mode coupling and Kerr effect hard and soft aperture mode coupling starting mechanisms for mode coupling orders of magnitude of physical properties of ultra short pulse lasers average power pulse peak power intensity light pressure strength of the electrical field energy transferred to electrons light-matter interaction warming an melting vaporizing and subliming photo disruption electron-phonon coupling time Coulomb explosion generation of hard x-rays cold material processing and its applications |
Skills | classify laser materials differentiate and classify transverse modes calculate quality factor and finess of a Fabry-Perot interferometer calculates the propagation of Gaussian beams calculate the stability of a resonator calculate the most important optical parameters of a laser choose a suitable laser and optical system for a given application All aquired knowledge is not ment to be fact based knowledge but should be inerconnected within by a deeper understanding of the underlying physical principles and intellectual transfer should be possible: - physics of laser light generation and physical properties of laser light - physics of light-matter interaction - diffraction theory |
Type | Attendance (h/Wk.) |
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Lecture | 2 |
Tutorial (voluntary) | 0 |
none |
Accompanying material | lecture notes as downloadable file |
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Separate exam | No |
Goal type | Description |
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Skills | - build a laser, align and start it - build a setup of measuring tranverse modes, measure traverse modes and calculate beam quality - measure axial modes, find out the free spectral range, the spectral bandwith of a single mode, the amplification bandwidth of a laser, the coherence length of a laser - build a diode pumped solid state laser - build a unit for frequency doubling and use it in combination with a diode pumped solid state laser. - write scientific report describe the task descirbe the idea of the solution explain the experimental setup explain the data processing make error analysis present the results and make a critical discussion |
Type | Attendance (h/Wk.) |
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Practical training | 2 |
Tutorial (voluntary) | 0 |
none |
Accompanying material |
Instrcutions for the experiments as downloadable files. Operating manuals for complex equipment as downloadable files. |
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Separate exam | Yes |
Exam Type | EN Projektaufgabe im Team bearbeiten (z.B. im Praktikum) |
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Details | 1) Written examination questions related to the experiment have to be prepared at home and shown at the beginning of the laboratory. 2) The underlying ideas of the experiment have to be explained at the beginning of the laboratory. 3) Make the experiment alone (preferred) or in a team of two. - Build up and adjust your own setup - Acquire / measure date with this setup 4) Write a documentation on the experiment. It will be checked wih regard to - completness - scientific and precise language - correctness - understanding of the interrellations and interpretation of the results |
Minimum standard | All written tasks must have been delt with. The basic ideas of the experiment must have been understood. All experiments must have been performed. The reports must be free of systematical errors. |
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