GB/T 20249-2006 in English

《GB/T 20249-2006声学 聚焦超声换能器发射场特性的定义与测量方法》由TC17（全国声学标准化技术委员会）归口，主管部门为中国科学院。
本标准规定了适用于聚焦超声换能器的声束轴准直方法。本标准适用于工作频率在0.5MHz至40MHz范围内，用于医学临床治疗和诊断的聚焦型超声换能器。

Scope

This standard provides the definition of the emission field characteristics of medical focused ultrasound transducers, and links these definitions with the theoretical description, engineering design and measurement of the emission field of focused ultrasound transducers. This standard gives the defined beam axis collimation method for focused ultrasound energy conversion. This standard applies to focused ultrasound transducers with operating frequencies in the range of 0.5MHz to 40MHz and used for medical clinical treatment and diagnosis. This standard describes how to measure and characterize the transducer's emission field from a design point of view when no prior knowledge of the structural details of a particular device is known. For the radiated ultrasonic field generated by the specified excitation method, the hydrophone is used to measure in the standard test medium (such as water) or a given medium. This standard applies only to media in which the acoustic field characteristics are substantially similar to those in fluids (the effects of shear waves and elastic anisotropy are minimal), including soft tissue and tissue gels. All sound field characteristics that affect its theoretical description, or are important in design, should be included. These definitions are useful in academic communication, system design, and in describing the performance and safety of systems employing these devices.