Patent ID: 7372578
Filing Date: 2008-05-13
Classification: G01B

Abstract:
1. An optical image measuring apparatus, comprising: light beam outputting means for outputting a light beam whose intensity is periodically modulated; dividing means for dividing the light beam into signal light propagating through an object to be measured and reference light propagating through a reference object; vibrating means for vibrating the reference object at a predetermined frequency with a predetermined amplitude; converting means for converting a polarization characteristic of one of the signal light and the reference light; superimposing means for superimposing the signal light propagating through the object to be measured and the reference light propagating through the reference object to be vibrated on each other to produce interference light, the signal light and the reference light respectively having a polarization characteristic converted by the converting means; extracting means for extracting two different polarized light components from the produced interference light by the superimposing means; two detecting means for detecting the two different polarized light components that have been extracted from the first interference; signal processing means for calculating one of a signal intensity and a phase of the interference light based on the polarized light components detected by the two detecting means to form an image of the object to be measured; and a controller configured to synchronize the predetermined frequency related to vibration of the reference object which is caused by the vibrating means with the frequency of the interference light, and to set the predetermined amplitude of the vibration to be equal to or smaller than the wavelength of the interference light.