Diodengepumpte Laserverstärker mit flachen Lasermedien
type: CreativeWork
description: Pulsed Laser-Oscillators are limited to a maximum output power depending on their regime of puls duration and repetition rate. The use of amplifiers enable higher power levels. The present theses reports on the development of laser amplifiers with a flat laser media and a special hybrid resonator, that can be used for a wide range of applications. The optical setup staring with the pump source, the active media and the resonator is described and methods for design and production are developed. Experimental results are given for a system of 10 ps puls duration and 50 W output power. The amplifier is running with high repetition rates as a quasi cw system and diffraction limited beam quality. The special slab shaped geometry of the crystal matches to the characteristic beam shape of high power diode laser bars. The radiation of the diode lasers is transformed to a homogeneous narrow line, that is imaged to the end face of the amplifier crystal. The use of a waveguide forms the homogeneous intensity distribution. Different waveguide concepts are introduced for the use of actively and passively cooled diode lasers. The pump unit is also usable for direct applications like laser welding of plastics or surface treatment of metal. The thermomechanical management of the slab crystal requires an efficient and constant cooling of two crystal side faces in order to achieve a minimum optical distortion of the amplifier beam. Heatsinks with different production techniques and geometries are described for the active conductive cooling of the laser crystal. The distribution of stress, expansion and temperature of the Nd:YAG and Nd:YVO4 crystals is calculated using FEM methods. The technological challenge is the packaging of the crystal and the heatsinks. The thermal contact of materials with different thermal properties has to enable a constant boundary condition in the contact plane on two faces of the crystal. Therefore different joining methods are tested and a new soldering me…
abstract: Pulsed Laser-Oscillators are limited to a maximum output power depending on their regime of puls duration and repetition rate. The use of amplifiers enable higher power levels. The present theses reports on the development of laser amplifiers with a flat laser media and a special hybrid resonator, that can be used for a wide range of applications. The optical setup staring with the pump source, the active media and the resonator is described and methods for design and production are developed. Experimental results are given for a system of 10 ps puls duration and 50 W output power. The amplifier is running with high repetition rates as a quasi cw system and diffraction limited beam quality. The special slab shaped geometry of the crystal matches to the characteristic beam shape of high power diode laser bars. The radiation of the diode lasers is transformed to a homogeneous narrow line, that is imaged to the end face of the amplifier crystal. The use of a waveguide forms the homogeneous intensity distribution. Different waveguide concepts are introduced for the use of actively and passively cooled diode lasers. The pump unit is also usable for direct applications like laser welding of plastics or surface treatment of metal. The thermomechanical management of the slab crystal requires an efficient and constant cooling of two crystal side faces in order to achieve a minimum optical distortion of the amplifier beam. Heatsinks with different production techniques and geometries are described for the active conductive cooling of the laser crystal. The distribution of stress, expansion and temperature of the Nd:YAG and Nd:YVO4 crystals is calculated using FEM methods. The technological challenge is the packaging of the crystal and the heatsinks. The thermal contact of materials with different thermal properties has to enable a constant boundary condition in the contact plane on two faces of the crystal. Therefore different joining methods are tested and a new soldering me…
author: Giesekus, Joachim
language: ger
keywords: info:eu-repo/classification/ddc/620, Ingenieurwissenschaften, YAG-Laser, Plattenlaser, Pumpen, Neodym-YAG-Laser, Laserverstärker, Laser, Diodengepumpter Laser, Lasertechnologie, Impulslaser, amplifier, slab, diode, waveguide
date published: 2007
date modified: 2026-07-30T19:43:10Z
provider: RWTH Aachen University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Publikationsserver der RWTH Aachen University