JPS63159729U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a vibration meter showing an embodiment of this invention, and FIG. 2 is a block diagram of a conventional vibration meter. In the figure, 13a and 13b are optical fiber cables,
14 is an optical connector, 15 is a collimator lens, 1
6 is a case. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] a laser that outputs a specific wavelength, a first beam splitter that splits the output beam of the laser into two, means for shifting the laser frequency of one of the two split laser beams by a specific frequency, and the frequency shifter. an optical fiber cable for transmitting a laser beam emitted from the optical fiber cable, a collimator lens capable of collimating the emitted laser beam of the optical fiber cable and irradiating it onto a vibrating object at a slight inclination angle in the vibration direction of the vibrating object; a condensing lens capable of condensing the scattered light that has undergone a Doppler shift depending on the speed in the specular reflection direction of the irradiation beam; an optical fiber cable that transmits the scattered light including the Doppler signal received by the condensing lens; a second beam splitter that mixes the scattered light transmitted by the optical fiber cable and the other laser beam that is not subjected to a frequency shift that was split by the first beam splitter; and electrically converts the mixed light. an amplifier for amplifying the output of the photodetector; a frequency tracker for detecting the Doppler frequency from the output signal of the amplifier; and a frequency tracker for detecting the Doppler frequency from the output signal of the frequency tracker, A vibration meter characterized by comprising a frequency-voltage converter capable of outputting an analog voltage proportional to speed.