Wu Y Q, Shankar P M, Lewin P A
Biomedical Engineering and Science Institute, Drexel University, Philadelphia, PA 19104.
Ultrasound Med Biol. 1994;20(7):645-53. doi: 10.1016/0301-5629(94)90113-9.
The PVDF (polyvinylidene fluoride) hydrophones, commonly used to measure the characteristics of ultrasonic transducers, suffer from a number of drawbacks. They disturb the field distribution to be measured and cause spatial averaging effects because of their finite aperture. In addition, they are very delicate and susceptible to damage. To overcome some of these problems, the authors previously proposed the use of an optical fiber-based probe to measure the ultrasonic fields. In this paper, this fiberoptic ultrasonic sensor is used to measure the characteristics of six transducers, focused as well as unfocused, covering a frequency range of 2.25 MHz to 20 MHz. Results obtained using the fiberoptic sensor are compared with those obtained using a calibrated PVDF needle hydrophone with an effective diameter of 0.5 mm. The temporal responses as well as the beam profiles of the transducers measured using the fiberoptic sensor show excellent agreement with the results obtained using the PVDF needle hydrophone.
常用于测量超声换能器特性的聚偏二氟乙烯（PVDF）水听器存在许多缺点。它们会干扰待测的场分布，并且由于其有限孔径会导致空间平均效应。此外，它们非常脆弱，容易损坏。为了克服其中一些问题，作者之前提出使用基于光纤的探头来测量超声场。在本文中，这种光纤超声传感器用于测量六个换能器的特性，包括聚焦和非聚焦的，频率范围为2.25 MHz至20 MHz。将使用光纤传感器获得的结果与使用有效直径为0.5 mm的校准PVDF针式水听器获得的结果进行比较。使用光纤传感器测量的换能器的时间响应以及波束轮廓与使用PVDF针式水听器获得的结果显示出极好的一致性。
