Development of an eye-safe solid-state tunable laser transmitter around 1.45 {_m63m [my-m] based on Cr_1hn4_1hn+:YAG crystal for lidar applications [Elektronische Ressource] / vorgelegt von Anna Petrova-Mayor

Development of an eye-safe solid-statetunable laser transmitter around 1.45μm4+based on Cr :YAG crystal for lidarapplicationsDissertation zur Erlangung des Doktorgradesder Naturwissenschaften (Dr. rer. nat.)Fakult¨at NaturwissenschaftenUniversit¨at HohenheimInstitut fu¨r Physik und Meteorologievorgelegt vonAnna Petrova-Mayoraus Vratsa, Bulgarien2008Thisthesiswasacceptedasadoctoraldissertationinfulfillmentoftherequirementsforthedegree“DoktorderNaturwissenschaften”bytheFacultyofNaturalSciencesat the Universityof Hohenheim, Stuttgart, Germany on 24 October 2007.Date of oral examination: 2 April 2008Examination committee:Supervisor and reviewer: Prof. Dr. V. WulfmeyerInstitute for Physics and Meteorology,University of HohenheimCo-reviewer: Prof. Dr. G. HuberInstitute for Laser Physics,University of HamburgAdditional examiner: Prof. Dr. K. JetterInstitute for AppliedMathematics and Statistics,University of HohenheimDean: Prof. Dr. H. BreerFaculty of Natural Sciences,University of HohenheimAbstract4+A gain switchedtunable Cr :YAGlaser was developedusing a Q-switchedflash-lamp–pumped Nd:YAG pump laser at 10Hz. A vacuum spatial filter (VSF) wasdesigned in order to filter the “hot spots” of the pump beam profile. As a result ofapplyingtheVSF,anearlyGaussian-shaped beamprofilewasachievedwhichenabled4+safe pumping of the Cr :YAG crystal with pulse energies in excess of 100mJ.