Title:
ディスパーション干渉計及び被測定物の物理量の計測方法
Document Type and Number:
Japanese Patent JP4925139
Kind Code:
B2
Abstract:
To provide a dispersion interferometer usable for actual time control, and capable of removing an influence of a high-frequency noise, reducing a measurement error caused by signal intensity change, and heightening accuracy, by extracting a phase from a signal intensity ratio of a fundamental wave and a double harmonic which are Fourier components of a modulated signal.
A nonlinear crystal element 10 of this dispersion interferometer changes a part of laser light (fundamental wave W1) into a double harmonic W2. A photoelastic element 12 generates phase modulation in the fundamental wave W1 as much as a modulated angle frequency ωmportion. A nonlinear crystal element 14 changes the fundamental wave W1 transmitted through plasma 30 into the double harmonic W2. A wavelength selection filter 16 allows selectively transmission of the double harmonic W2. The interferometer determines an intensity ratio between a fundamental wave component of the modulated angle frequency ωmand a double harmonic component in an interference signal, and calculates a line average electron density which is a physical quantity of the plasma 30 based on the intensity ratio and a phase variation.
COPYRIGHT: (C)2010,JPO&INPIT
Inventors:
Takeshi Akiyama
Kawabata Kazuo
Shigeki Okajima
Kazuya Nakayama
Application Number:
JP2008282085A
Publication Date:
April 25, 2012
Filing Date:
October 31, 2008
Assignee:
National Institute for Natural Sciences
International Classes:
G01N21/45; G01B9/02; G01B11/06; G01J9/02
Domestic Patent References:
| JP10500767A | | | | |
| JP2008281484A | | | | |
| JP2005517913A | | | | |
Other References:
Drachev V P , et.al.,Nonlinear phase characteristics of the dispersion interferometer at high-intensity pulses,Optics Communications,1996年10月 1日,Vol.130,pp.402-412
Attorney, Agent or Firm:
Hironobu Onda
Makoto Onda
