论文标题
亚波长束使用球形镜头进行超声成像
Subwavelength beam focusing using a ball-shaped lens for ultrasound imaging
论文作者
论文摘要
可以通过（Super）聚焦原声梁到亚波长度或使用基于算法的方法来生成超声波超分辨率图像。在这里，我们证明了由球形透镜超级焦点的超声脉冲可用于产生超分辨率图像。成像系统由一个圆形的平换灯组成，其操作频率为$ 1 $ MHz，并且是以对称性的光束轴为中心的球镜头。水中的相应波长为$λ_0= 1.53 $ mm。系统分辨率在焦平面上的$0.6λ_0$，距离镜头一个波长。将超分辨率方法与基于球体浓缩换能器的常规超声系统进行了比较。我们的方法提出了两倍的分辨率，较短的景点为$2λ_0$。讨论了利用这些功能的可能应用，以及提出的技术的某些局限性。
Ultrasonic superresolution images can be generated by means of (super) focusing acoustic beams to subwavelength dimensions or using algorithm-based methods. Here, we demonstrate that ultrasonic pulses which are superfocused by a ball-shaped lens can be used to produce superresolution images. The imaging system is comprised of a circular flat transducer with an operation frequency of $1$ MHz, and a ball lens centered in the beam axis of symmetry. The corresponding wavelength in water is $λ_0 = 1.53$ mm. The system resolution is $0.6λ_0$ in the focal plane at one wavelength away from the lens. The superresolution method is compared with a conventional ultrasonic system based on a spherically focused transducer. Our method presents twice more resolution with a shorter depth-of-field of $2λ_0$. Possible applications that take advantage of these features are discussed, as well as some limitations of the proposed technique.
