Patent ID: 7345770
Filing Date: 2008-03-18
Classification: A61B,G01B,G01P

Abstract:
1. An optical image measuring apparatus, comprising: light beam outputting means for outputting a light beam whose intensity is periodically modulated at a modulation frequency, the light beam being low-coherent; increasing means for increasing a beam diameter of the outputted light beam; a first converting means for converting a polarization characteristic of the light beam to linear polarization; light beam dividing means for dividing the light beam into signal light propagating to an object to be measured and reference light propagating to a reference object; a second converting means for converting a polarization characteristic of one of the signal light and the reference light, which are linearly polarized light; superimposing means for superimposing the signal light whose part propagating through a moving matter in the object to be measured is subjected to frequency shift and the reference light propagating through the reference object on each other to produce superimposed light including interference light having a beat frequency corresponding to a quantity of the frequency shift, in which one of the signal light and the reference light is the linearly polarized light acquired by the first converting means and the other thereof has the polarization characteristic acquired by the second converting means; at least one two-dimensional photo-detection means for receiving a plurality of different polarized light components of the interference light included in the produced superimposed light, and outputting a detection signal including interference frequency components corresponding to beat frequencies of the interference light; and image forming means for forming a velocity distribution image expressing a moving velocity distribution of the moving matter based on an interference frequency component corresponding to a beat frequency substantially equal to the modulation frequency at which the intensity of the light beam is modulated by the light beam outputting means, among the interference frequency components included in the outputted detection signal.