使用射频变压器制造贝塞尔束
概括
研究人员开发了一种使用单个射频 (RF) 功率放大器创建宽带贝塞尔束的新方法,从而减少高级超声波成像应用的尺寸和功率.
科学领域:
- 声学和波浪现象
- 医学成像技术
- 材料科学
背景情况:
- 贝塞尔束提供无衍射的传播和很大的视野深度,非常适合各种应用.
- 传统的超声波贝塞尔束产生需要体积大,耗电多的多放大器系统,限制了可穿戴应用.
研究的目的:
- 为超声波应用开发一个紧且高效的宽带贝塞尔束产生方法.
- 在可穿戴医疗成像和超分辨率成像中实现贝塞尔束应用.
主要方法:
- 使用单个高压射频 (RF) 功率放大器和定制的射频变压器.
- 使用自定义的10环,2.5MHz宽带环状阵列变频器,由PZT陶/聚合物复合材料制成.
- 在水中生成的脉冲贝塞尔束大约在+/- 90V.
主要成果:
- 实现了与多个放大器,模拟和理论相比的脉冲贝塞尔束.
- 证明了大约2.53毫米 (4.22波长) 的-6dB光束宽度.
- 获得了大约216毫米 (360波长) 的显著深度.
结论:
- 这种新方法显著降低了贝塞尔束生成系统的尺寸,重量和功耗.
- 这种进步有助于将贝塞尔束集成到可穿戴超声波设备中.
- 使用扫描反射器的贝塞尔束进行3D和多平面成像.
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