基于传统的迈克尔逊干涉仪, 提出了微振动的四路平衡测量法。该方法无需PZT外加高频载波调制, 通过在光路上获得的四路正交信号来取代常见的由相位载波零差解调法在电路上获得的两路正交信号, 克服了PZT高频调制下的非线性效应, 并简化了解调电路。同时, 四路平衡法也降低了光源的强度噪声。通过合成利萨如图形, 验证了四路信号的正交特性。实验结果表明, 该方法能实现微振动信号的测量, 对微振动位移的测量范围可以达到5～775 nm。

Based on the traditional Michelson interferometer,the four-channel balancing method for micro-vibration measurement system is built. The method without using PZT to generate high frequency carrier wave realizes four orthogonal signals by using four-channel-balancing detection instead of using PGC demodulation circuit. This method overcomes the nonlinearity of PZT, simplifies the demodulation circuit,and reduces the intensity noise of laser source, simultaneously. Through the Lissajou figure which is synthesized by the four signals, the four signals are proved to be orthogonal. The experimental results show that this method can realize the measurement of micro-vibration, and the micro-vibration displacements measuring range can be up to 5～775 nm.