Heterodyne interferometer of coaxial CO/sub 2/ and He--Ne lasers for plasma density measurements

Journal Article · Tue Jul 01 00:00:00 EDT 1986 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1138644· OSTI ID:5791917

Takahashi, H; Kimura, M; Sano, R; Nagayama, Y; Miyamoto, K

An interferometer using coaxial CO/sub 2/ and He--Ne lasers has been developed for electron density measurements in the reversed field pinch plasma. The interferometer uses the phase modulating heterodyne detection of 60 MHz. The CO/sub 2/ laser interferometer is free from the mechanical vibrations due to the reduction of the vibrations by the air springs and the compensation of the vibrations by the He--Ne laser interferometer. The electron density measurement during a long-time discharge of 50 ms without the disturbance by the vibrations is achievable. The resolution is less than 1/100 fringe of the CO/sub 2/ laser interferometer, therefore the electron line density as small as 1.1 x 10/sup 14/ electrons/cm/sup 2/ is detectable.

• Research Organization: Matsushita Research Institute Tokyo, Inc., Higashimita Tama-ku, Kawasaki 214, Japan
• OSTI ID: 5791917
• Journal Information: Rev. Sci. Instrum.; (United States), Vol. 57:7
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
INTERFEROMETERS
DESIGN
PERFORMANCE
PLASMA DIAGNOSTICS
INTERFEROMETRY
REVERSE-FIELD PINCH
ELECTRON DENSITY
CARBON DIOXIDE LASERS
HELIUM-NEON LASERS
HETERODYNE RECEIVERS
ELECTRONIC EQUIPMENT
EQUIPMENT
GAS LASERS
LASERS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
PINCH EFFECT
RADIO EQUIPMENT
700102* - Fusion Energy- Plasma Research- Diagnostics