Speaker
Mr
Jibo Zhang
(Institute of Plasma Physics, Chinese Academy of Science)
Description
A heterodyne interferometer operating at the frequency f = 890 GHz has been designed for measuring electron densities of atmospheric pressure air plasmas its density range is from $10^9$ to $3\times 10^{13}$ cm$^{-3}$ and the pressure range is from 1 Pa to 20 kPa. The system is configured as a Mach-Zehnder type interferometer. The light source is hydrogen cyanide (HCN) laser with wavelength of 337 $\mu$m, which are suitable for the high density of atmospheric pressure air plasmas. The HCN laser power is up to 100 mW. The intermediate frequency, shifted by 500 kHz, is generated by the Doppler shift with a super high speed rotating grating, which is installed in a vaccum vessel. So the temporal resolution of the HCN interferometry is reach to 2 $\mu$s. Beam path analysis based on Gaussian optics is used in the design of the optical system. VDI planar-diode Integrated Conical Horn Fundamental Mixers optimized for high sensitivity, typical 750 V/W, will be used in the HCN interferometry. The detailed optical design and opto-mechanical design of the HCN interferometry are presented.
Primary author
Mr
Jibo Zhang
(Institute of Plasma Physics, Chinese Academy of Science)
Co-authors
Mr
Haiqing Liu
(Institute of Plasma Physics, Chinese Academy of Science)
Mr
Liqun Hu
(Institute of Plasma Physics, Chinese Academy of Science)
Mr
Xuechao Wei
(Institute of Plasma Physics, Chinese Academy of Science)
Mr
Yinxian Jie
(Institute of Plasma Physics, Chinese Academy of Science)
