中文摘要：

运用长距离显微成像系统与锁相积分拍摄技术相结合的方法,拍到了单个造影剂微泡在两种不同频率和不同声压下的周期性振动图像.根据这些图像得到了微泡直径的实验数据,并分别用Hoff模型和Rayleigh-Plesset模型对数据进行拟合,并对数据进行了频谱分析.结果表明：Hoff模型对实验数据的拟合结果优于Rayleigh-Plesset模型的拟合结果;二次谐波的相对强度随着声压幅度的升高而增大.

英文摘要：

Using a long-distance microscope imaging system and a lock-in phase integrate technique, optical measurements demonstrate that the evolutional behaviors of a phospholipid-shelled micro-bubble, a kind of ultrasound contrast agent, under two ultrasound frequencies and different pressures. Dozens of frames of an oscillating microbubble for one acoustic cycle are captured. The experimental data of micro-bubble diameter are fit by the numerical calculations of the Hoff model and the Rayleigh-Plesset model, respectively. The results show the good agreement between experimental data and the theoretical calculation in the Hoff model. In addition, the spectral analysis based on the experimental data indicates that the relative intensity of the second harmonic increases with the driving pressure amplitude.