National Institute of Advanced Industrial Science and Technology (AIST) This page is a page of the former research institute. We stopped updating on March 31.2001.
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Optical Measurement Section, NRLM, AIST

Intelligent Optical Measuremnet

  1. 2 color interferometry
    Two types of 2 color laser interferometers have been developed, where Nd:YAG laser and its SHG have been used as light sources. One is for ultra-fine displacement measurements. Utilizing dispersion of atmosphere, small displacement d detected by one of 2 colors is canceled by changing path length of superposed 2 color beam. The displacement d is enhanced 300,000 times in the superposed path length. The other is for correction of refractive index of the air. To realize high accuracy in air, this method is effective.

  2. Laser control
    For measurement light sources of green color, Nd:YVO4 and Nd:YAG Lasers were stabilized in their frequencies by means of linear absorption of SHG by iodine molecular.