SELF-MIXING TYPE LASER DOPPLER VIBRATION METER

摘要

PROBLEM TO BE SOLVED: To improve resolution by increasing a beat wave number measured in a half period of vibration of an object, without shortening the wavelength of a laser beam or adding an AO modulator or the like.;SOLUTION: This laser Doppler vibration meter is equipped with a light- emitting part 12 for irradiating the laser beam L1 toward the object M, a reflection part 14 for reflecting the laser beam L2 reflected by the object M and irradiating the beam again toward the object M, a light-receiving part 94 for receiving the laser beam L4 reflected by the object M via the reflection part 14 and converting the beam into an electric signal S, and a signal processing part 96 for obtaining information on vibration of the object M based on a beat wave B included in the electric signal S. As the laser beam L4 receives frequency deviation twice, the resolution is improved twice.;COPYRIGHT: (C)2001,JPO