A tunable diode laser-based sensor for remote sensing of methane (CH4) leakage at a wavelength of 1,65 um was developed. The 1.65 um distibuted feedback (DFB) diode laser has a narrow line width and wide tuning range. It was found that the sensor nac detect a 10 cm3 min -1 city-gas leak with a sensor output equivalent to the range-integrated concentration over 100 ppm m.
2
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
A compact DFB tunable diode laser operating around 1.572um was used to study the cavity enhanced absorption spectroscopy of carbon dioxide near 1.572 um. It was experimentally demonstrated that a narrow-band continuous wave laser could be used in combination with a high-finesse optically stable cavity to perform highly sensitive direct absorption spectroscopy using ideas from the field of cavity ring down spectroscopy in a simple experimental setup. Laser radiation was coupled into optical cavity via accidental coincidences of laser frequency with one ofmultitude modes of the cavity. Absorption spectrum of carbon dioxide was obtained, the absorption signals were extracted from the measurement recording only the highest light intensity that leaked out of the optical cavity. A wavemeter was used to record accurate frequency of the laser. An absorption sensitivity of about 3.39x10-7cm-1 has been achieved.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.