Patent ID: 7777891

Claim:
An elasticity and viscosity measuring apparatus comprising: excitation light generating means for generating modulated excitation light; an optical system for focusing the excitation light to a focusing position on a measurement object and capturing scattered light generated by the measurement object; locally oscillated light generating means for generating locally oscillated light; multiplexing means for multiplexing the captured scattered light and locally oscillated light; optical detection means for photoelectrically converting the multiplexed light and generating a photoelectric current; a filter for selecting and extracting part of an AC component of the photoelectric current; frequency-selective power detection means for selecting and measuring, based on the electric power of the extracted photoelectric current, a frequency component related to modulating the excitation light; and analyzing means for calculating the light spectrum of the scattered light and obtaining at least one parameter selected from the strength of the scattered light, the frequency, and the linewidth based on the elastic waves in the measurement object; wherein the optical system selects and captures part of the scattered light that forms an angle of 90 degrees or greater in relation to the wave number vector of the excitation light.