| 摘要 |
A method and apparatus are disclosed for characterizing a vibrating image (54) of an object (12). Two or more wavefronts are provided, with at least one of the wavefronts (26) being modulated by interaction with the vibrating medium (14) of the object (12). The other wavefront (30) is modulated such that the difference frequency between the one wavefront (26) and the other wavefront (30) is within a response range of the sensing media (44). The modulated one wavefront (30) and other wavefront (26) are combined in association with the sensing media (44) to interfere and produce simultaneous vibration measurements that are distributed over the object (12) so as to provide an image (54) of the vibrating medium (14). The image (54) has an output intensity that is substantially linear with small physical variations within the vibrating medium (14). In one implementation, the apparatus comprises a vibration spectrum analyzer (10) having an emitter (16), a modulator (38), sensing media (44) and a detector (50) configured so as to realize such method. |
