Sökning: "Picosecond laser"
Visar resultat 1 - 5 av 37 avhandlingar innehållade orden Picosecond laser.
Sammanfattning : Light detection and ranging (lidar), a method for nonintrusive, single-ended, and range resolved measurements, has been developed and applied for combustion related diagnostics. Employing picosecond laser pulse durations and detectors providing temporal resolution on the order of picoseconds, lidar has been applied successfully for both quantitative temperature- and species concentration measurements, obtaining an ultimate range resolution of 0. LÄS MER
Sammanfattning : The subject of this thesis is the investigation of novel technologies for mode-locking of diode-pumped, solid-state lasers. Novel saturable absorbers are used: quantum dots (QDs) and carbon nanotubes (CNTs), which both are low-dimensional nano-formations. In addition, mode-locking by cascaded nonlinearities is explored. LÄS MER
Sammanfattning : Elastic scattering and the Lorenz-Mie (LM) theory in particular is used for the characterization of sub-micron- and micron-sized droplets of organic fuels in sprays and aerosols. Calculations on the Lorenz- Mie theory show that backward-sideward scattered visible radiation can be used for unambiguous detection of ensembles of homogeneous droplets of organic substances with diameters around 1 micrometer (size parameter between 2 and 6). LÄS MER
4. Nonlinear optical techniques for ultrafast laser diagnostics : Development of femtosecond LIF, LIGS, CARS and backward lasing
Sammanfattning : The thesis work concerns development and application of four versatile nonlinear optical techniques, based on exploiting ultrashort laser pulses, for diagnostic purposes in gases and flames. The four techniques, all laser-based, are two-photon laser-induced fluorescence (TPLIF), hybrid femtosecond/nanosecond (fs/ns) rotational coherent anti-Stokes Raman scattering (fs/ns RCARS), fs-laser-induced grating spectroscopy (fs-LIGS), and backward lasing. LÄS MER
Sammanfattning : Laser based diagnostic tools have had an exploding impact on fundamental as well as applied research in a number of disciplines, such as biomedicine, physical chemistry etc over the last decades. Whereas fundamental research often investigate phenomena in extreme conditions, applied research aims at performing in-situ measurements, in order to understand the many aspects and entangled phenomena that affects the research of interest. LÄS MER