Broadband optical ultrasound sensor with a unique open-cavity structure

Broadband optical ultrasound sensor with a unique open-cavity structure.

High-resolution ultrasound imaging requires quality sensors with wide bandwidth and high sensitivity, as shown in a wide range of applications, including intravascular imaging of cardiovascular diseases. However, piezoelectric technology, the current dominant approach for hydrophone fabrication, has encountered many technical limitations in the high-frequency range. Using optical techniques for...

Parametric analysis of a broadband Archimedean spiral antenna with cavity

In this article an Archimedean spiral antenna is designed and analyzed that has good operation in broadband application. By analyzing this design, the effects that different parameters have on antenna operation will be studied and ways of optimization will be found.  Influences of cavity height and number of turns to obtain good matching and gain in a frequency interval of 4 to 18 GHz will be d...

Broadband All-Optical Ultrasound Transducer

Real-time three-dimensional (3D) high-resolution ultrasound imaging requires 2D phased arrays operating at frequencies higher than 50 MHz, which poses a great challenge for piezoelectric technologies. A promising alternative is an optoacoustic array relying on optical generation and detection of ultrasound. We present an all-optical ultrasound transducer, which consists of a 2D gold nanostructu...

Numerical investigation and optimization of a mechano - optical sensor based on a grated waveguide optical cavity

Computation of optical modes in axisymmetric open cavity resonators

The computation of optical modes inside axisymmetric cavity resonators with a general spatial permittivity profile is a formidable computational task. In order to avoid spurious modes the vector Helmholtz equations are discretised by a mixed finite element approach. We formulate the method for first and second order Nédélec edge and Lagrange nodal elements. We discuss how to accurately compute ...