Hou Yubin, Lu Qingyou
High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.
Sensors (Basel). 2014 Nov 19;14(11):21941-9. doi: 10.3390/s141121941.
We have measured the coefficient of the voltage induced frequency shift (VIFS) of a 32.768 KHz quartz tuning fork. Three vibration modes were studied: one prong oscillating, two prongs oscillating in the same direction, and two prongs oscillating in opposite directions. They all showed a parabolic dependence of the eigen-frequency shift on the bias voltage applied across the fork, due to the voltage-induced internal stress, which varies as the fork oscillates. The average coefficient of the VIFS effect is as low as several hundred nano-Hz per millivolt, implying that fast-response voltage-controlled oscillators and phase-locked loops with nano-Hz resolution can be built.
我们测量了一个32.768 KHz石英音叉的电压感应频率偏移（VIFS）系数。研究了三种振动模式：一个叉指振荡、两个叉指同向振荡以及两个叉指反向振荡。由于电压感应内应力随音叉振荡而变化，它们的本征频率偏移均呈现出相对于施加在音叉两端的偏置电压的抛物线依赖性。VIFS效应的平均系数低至每毫伏几百纳赫兹，这意味着可以构建具有纳赫兹分辨率的快速响应压控振荡器和锁相环。
