| 摘要 |
PROBLEM TO BE SOLVED: To achieve long distance and high spatial resolution, in a light reflection measurement technique using correlation.SOLUTION: Light emitted from a laser light source 1 having a coherence time τis branched into two lights, by light branch means 2, one of the branched lights is probe light, the other is reference light, a delay time is provided within a time in which respective lights are modified by light phase modification means 3-1, 3-2, then the probe light and reference light which are back scattered from inside of a measured device 6, are multiplexed by light multiplexing means 9, then, from the multiplexed light, an interference component of the probe light and reference light is detected by a balance light reception unit 10. Then, a time for modifying the probe light and reference light is controlled using trigger source control means 8.SELECTED DRAWING: Figure 1 |
