title: Development of a phase contrast imaging system based on a yttrium aluminum garnet laser with folded beam for observations of density fluctuations in compact helical system.
abstract: A near-infrared laser phase contrast optical system incorporating a folded beam was developed in order to measure the distribution of density fluctuations in a high-temperature plasma. The coherent light source used was an yttrium aluminum garnet laser stabilized by a ring oscillator. The probe beam system separates and reflects the incident and exiting beams with a polarizer and a fully reflective mirror with a waveplate. This system was employed with a compact helical system to detect fluctuations at the plasma edge.
authors.affiliation: Fukuoka Institute of Technology, 3-30-1 Wajirohigashi Higashi-ku, Fukuoka-shi, Fukuoka 811-0295, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Matsuo
authors.forename: N
authors.initials: N
authors.lastname: Uchida
authors.forename: M
authors.initials: M
authors.lastname: Kawakubo
authors.forename: H
authors.initials: H
authors.lastname: Iguchi
authors.forename: S
authors.initials: S
authors.lastname: Okamura
authors.forename: K
authors.initials: K
authors.lastname: Matsuoka
authors.forename: T
authors.initials: T
authors.lastname: Akiyama