Interferometer have already been commercialized and utilized in various fields, but it is too weeak to enviromental condition, its performance remains significantly limited. Therefore, research continues to apply advanced measurement techniques in various fields, such as optical measurement technology for gravitational wave detectors and large-aperture optical measurement technology. In this talk, I will introduce about birefringence sensor for test mass of gravitational wave detector and interferometric sensor for lareg-scale optics. In addition scattered light analysis from large scale optics will be introduced.