Sökning: "frequency-modulation spectroscopy"
Visar resultat 1 - 5 av 6 avhandlingar innehållade orden frequency-modulation spectroscopy.
1. Diode laser spectroscopy in extended wavelength ranges
Sammanfattning : Diode laser spectroscopy performed in the ultraviolet, visible and infrared spectral regions is presented. The accessible wavelength range for visible and near-infrared diode lasers is extended by the use of sum- and difference-frequency generation. LÄS MER
2. Near-infrared gas analysis spectroscopy systems with semiconductor lasers
Sammanfattning : .... LÄS MER
3. Environmental Monitoring - using diode-laser-based spectroscopic techniques
Sammanfattning : Monitoring of environmental gases is necessary to understand the complex processes governing global warming and the impact of pollutant emissions related to human activity. Diode-laser-based spectroscopic techniques, being robust and affordable, have a great potential to become an industrially well-established technology for environmental sensing. LÄS MER
4. Further development of NICE-OHMS : – an ultra-sensitive frequency-modulated cavity-enhanced laser-based spectroscopic technique for detection of molecules in gas phase
Sammanfattning : Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy, NICE-OHMS, is a laser-based spectroscopic detection technique that comprises the concepts of frequency modulation (FM, for reduction of 1/f-noise by detecting the signal at a high frequency) and cavity enhancement (CE, for a prolongation of the optical path length) in a unique way. Properly designed, this gives the technique an intrinsic immunity against the frequency-to-noise conversion that limits many other types of CE techniques. LÄS MER
5. Fiber-laser-based noise-immune cavity-enhanced optical heterodyne molecular spectrometry
Sammanfattning : Noise-immune cavity-enhanced optical heterodyne molecular spectro-metry (NICE-OHMS) is one of the most sensitive laser-based absorption techniques. The high sensitivity of NICE-OHMS is obtained by a unique combination of cavity enhancement (for increased interaction length with a sample) with frequency modulation spectrometry (for reduction of noise). LÄS MER