物电学院第十期学术沙龙

主办：现代光学技术应用研究所
时间：2014年10月24日下午2:30
地点：理六栋2楼多功能厅
报告人： 黄佐华教授
题目：Quantitative Measurement of Phase Variation Amplitude of Ultrasonic Diffraction Grating Based on Diffraction Spectral Analysis
摘要：A new method based on diffraction spectral analysis is proposed for the quantitative measurement of the phase variation amplitude of ultrasonic diffraction grating. For a traveling wave, the phase variation amplitude of the grating depends on the intensity of the zeroth- and first-order diffraction waves. By contrast, for a standing wave, this amplitude depends on the intensity of the zeroth-, first-, and second-order diffraction waves. The proposed method is verified experimentally. The measured phase variation amplitude ranges from 0 to 2π, with relative error of approximately 5%. A nearly linear relation exists between the phase variation amplitude and driving voltage. Our proposed method can also be applied to ordinary sinusoidal phase grating.