PHASE SHIFT SPECKLE INTERFEROMETER USING QUARTER WAVELENGTH PLATE AND POLARIZER

摘要

PURPOSE: A phase shift speckle interferometer is provided to simplify system configuration and rapidly obtain degree of phase of a sample by using an inexpensive quarter wavelength plate and polarizer. CONSTITUTION: A phase shift speckle interferometer comprises a light wavelength expander(20) for expanding width of the light wavelength generated from a laser(10) serving as a light source; a light wavelength divider(30) for dividing the light wavelength output from the light wavelength expander into a first light wavelength and a second light wavelength; a first reflector plate(40a) and a second reflector plate(40b) for reflecting first and second light wavelengths divided by the light wavelength divider; a quarter wavelength plate(50) for changing polarizing direction of the incident first light wavelength; a polarizing plate(60) for selectively transmitting polarized light of the first light wavelength rotated by the quarter wavelength plate; a camera(80) for photographing interference caused between the first light wavelength passed through the polarizing plate and radiated to a sample(70) and the second light wavelength directly radiated to the sample; and a computer(90) for calculating degree of phase of interference in accordance with the images photographed by the camera.