An arbitrary waveform optical frequency modulation device and method

Abstract

An optical frequency modulation excitation device and method disclosed by the invention belong to the technical field of photoelectric measurement. The present invention mainly consists of a laser vibrometer, a first λ / 2 wave plate, a second λ / 2 wave plate, a third λ / 2 wave plate, a first polarization beam splitter, a second polarization beam splitter, and a third polarization beam splitter , the first lens, the second lens, the first plane mirror, the second plane mirror, the third plane mirror, the first acousto-optic modulator, the second acousto-optic modulator, FM signal source, arbitrary wave generator, composed of sinusoidal signal sources. The invention uses an optical frequency modulation method to generate arbitrary waveform excitation of simulated vibration, and can be used as an excitation source for the evaluation of the characteristics of a laser vibrometer, avoiding the problem that the technical parameters of mechanical movements such as a vibrating table cannot completely cover the range of the vibrometer, and improving the excitation source. The stability of the standard laser vibrometer can be traced to the source. The invention has faster rise time, wider frequency range, larger amplitude range and more complex and changeable waveform characteristics.

Description

technical field [0001] The invention relates to an arbitrary waveform optical frequency modulation device and method, belonging to the technical field of photoelectric measurement. Background technique [0002] The laser vibrometer is a general-purpose, basic vibration and shock measuring instrument with high precision, non-contact, and no additional interference and influence on the measured object. Its measurement calibration and performance evaluation have always been difficult problems in the industry. The main reasons are: 1) Its excitation is the movement value (displacement, velocity, acceleration), and the measurement principle used is carried out through the laser Doppler effect, which needs to perceive physical movement through the change of optical frequency, and the output is based on electrical signal data The results are given in different forms, involving different aspects such as mechanical movement, optical frequency control, electronic measurement, etc. 2)...

AI Technical Summary

Problems solved by technology

[0003] Aiming at the main problems in the measurement calibration and performance evaluation of the laser vibrometer, which are limited by the mechanical movement of the vibrating table, the technical parameters cannot completely cover the range of the vibrometer and the stability is not as good as that of the vibrometer, and the standard laser vibrometer traceability The problem that cannot be completely solved, the technical problem to be solved by an optical frequency modulation excitation device and method disclosed in the present invention is: use optical frequency modulation to generate arbitrary waveform excitation of analog vibration, and can be used as an evaluation of the characteristics of the laser vibrometer The excitation source avoids being limited by the technical parameters of the vibration table and other mechanical movements, which cannot completely cover the range of the vibrometer, improves the stability of the vibrometer, and realizes the traceability of the standard laser vibrometer.

Images