Patent ID: 7907285
Filing Date: 2011-03-15
Classification: G01M

Abstract:
1. A scattered light measuring device comprising: a continuous wave light source that generates continuous wave light; an optical pulse generator that converts the continuous wave light into pulsed light; an optical frequency shifter that receives the continuous wave light, and outputs a shifted light including the continuous wave light, first sideband light having an optical frequency higher than an optical frequency of the continuous wave light by a predetermined optical frequency, and second sideband light having an optical frequency lower than the optical frequency of the continuous wave light by the predetermined optical frequency; a power reducer that reduces the power of the continuous wave light in the shifted light output by said optical frequency shifter; and a heterodyne optical receiver that receives scattered light from an incident end of an optical fiber which the pulsed light enters, further receives the shifted light from said optical frequency shifter, and outputs an electric signal having a frequency which is a difference between the optical frequency of the scattered light and the optical frequency of the shifted light.