PLASMA DIAGNOSIS SYSTEM USING MULTIPLE-RECIPROCATING-PASS THOMPSON SCATTERING

摘要

Provided is a plasma diagnosis system using multiple-reciprocating-pass Thompson scattering. The plasma diagnosis system includes: a laser which supplies laser pulses; an optical system configured to make the laser pulse multiple roundtrips, focus the laser pulse to a predetermined position, rotate the plane of polarization by 90 degrees in every completion of the roundtrip; a collection optics which collects lights scattered from the focused region in plasma, which the collected light by the vertical polarization of the laser pulse is referred to as ‘first collected scattering’ and the collected light by the horizontal polarization of the laser pulse is referred to as ‘second collected scattering’; and a polychromator which measures spectral characteristics of the first and second collected scatterings and outputs Thomson scattering signal with the background noise and the background noise without Thomson scattering signal.