Ultrasound vision improved

Imaging systems that use high-frequency ultrasound generated by a transducer are currently widely used in medical diagnostics, but the images captured are often of a low quality. In May Journal of Micromechanics and Microengineering, Jinghong Li and colleagues from Louisiana Tech University, Ruston, USA, describe the design and fabrication of a miniaturized, high-frequency acoustical lens-transducer system that can examine smaller regions and can obtain detailed information — and a much sharper image.

Li et al. used state-of-the-art micromachining technology to fabricate a high-precision, integrated, microacoustical lens-transducer system of identical geometric shape. They made concave lenses of 1mm diameter (from either PMMA® or epoxy) for three different focal lengths (3, 4 or 5 mm) and with a center thickness of (3/4)λ (J Micromech Microeng 2002, 12:219-228). Acoustical lenses focus sound waves in a manner similar to the way a standard optical camera lens focuses a light.

"When...