@inproceedings{9aa292581c45469692c50a10370e5df1,
title = "Real-time gas density measurement using a ring cavity Terahertz parametric oscillator",
abstract = "We carried out real-time measurement of gas density using monochromatic terahertz waves. The THz-wave absorbance is useful to measure the density of a gas having a characteristic spectrum in the THz region. We used the ring cavity THz-wave parametric oscillator (ring-TPO) as a monochromatic tunable THz-wave source. One can change the oscillation frequency of ring-TPO with a rotating galvano mirror forming the ring cavity. The frequency can be changed by synchronization with a repeating pump-pulse of 500 Hz. We demonstrated real-time measurement of the gas density in R-22, which had some spectral structure in THz frequency region. The gas density in the sample cell was changed by controlling the pressure to lower than 1 atm. When the gas density in the cell was the most tenuous, the maximum sensitivity was about 5%, which was limited by the fluctuation of THz-wave intensity.",
keywords = "Gas sensing, R-22, Terahertz parametric oscillator",
author = "S. Ohno and R. Guo and H. Minamide and H. Ito",
year = "2007",
month = nov,
day = "19",
doi = "10.1117/12.722706",
language = "English",
isbn = "0819467103",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
booktitle = "Nonlinear Optics and Applications II",
note = "Nonlinear Optics and Applications II ; Conference date: 16-04-2007 Through 18-04-2007",
}