Radial and azmuthal non-resonant open-tubular optoacoustic cell

摘要

A radial or azmuthal non-resonant flow-through optoacoustic cell is operated without windows, completely eliminating the window background interference. The cell is constructed of an elongated tube the length of which is 34x103cmx1/f, where f is the light source modulating frequency and is made of conducting material which is perforated along the center one-half length with holes. A metalized sheath surrounds this center region to form a capacitor microphone.