Review of Laser-Generated Ultrasound Transmitters and Their Applications to All-Optical Ultrasound Transducers and Imaging

Abstract

Abstract:Medical ultrasound is an imaging technique that utilizes ultrasonic signals as information carriers, and has wide applications such as seeing internal body structures, finding a source of a disease, and examining pregnant women. The most commonly used ultrasonic transducer today is based on piezoelectricity. The piezoelectric transducer, however, may have a limited bandwidth and insufficient sensitivity for reduced element size. Laser-generated ultrasound (LGUS) technique is an effective way to resolve these issues. The LGUS approach based on photoacoustic effect is able to greatly enhance the bandwidth of ultrasound signals and has the potential for high-resolution imaging. High-amplitude LGUS could also be used for therapy to accomplish high precision surgery without an incision. Furthermore, LGUS in conjunction with optical detection of ultrasound allows all-optical ultrasound imaging (i.e., ultrasound is generated and received optically). The all-optical platform offers unique advantages in providing high-resolution information and in facilitating the construction of miniature probes for endoscopic ultrasound. In this article, a detailed review of the recent development of various LGUS transmitters is presented. In addition, a recent research interest in all-optical ultrasound imaging, as well as its applications, is also discussed.

Source Density Apodization: Image Artifact Suppression Through Source Pitch Nonuniformity

“…Recently, an all-optical alternative to electronic ultrasound transducers has been presented that uses light to both transmit and receive ultrasound. Using fibre optic technology, optical ultrasound sources [3][4][5][6][7][8] and detectors [9][10][11][12][13][14] are readily miniaturised, exhibit high bandwidths and sensitivities, and are immune to electromagnetic interference. Recently, a benchtop system has been demonstrated that used a single fibre optic ultrasound detector and a centimetre-scale monolithic photoacoustic ultrasound generator membrane to achieve video-rate two-dimensional imaging [15].…”

The Progress in Photoacoustic and Laser Ultrasonic Tomographic Imaging for Biomedicine and Industry: A Review

“…This trend of object diagnostics is similar to conventional ultrasonic diagnostics and echoscopy [67]. Active research is being conducted to find better materials for PA generators [68]. The advantage of the LU method, compared with other methods, is laser generation of short and intense aperiodic ultrasonic pulses, inaccessible to the usual ultrasonic transducers [69,70].…”

Laser generated ultrasound sources using polymer nanocomposites for high frequency metrology

“…However, laser generated ultrasound is a promising technique in this regard. It is possible to generate a broadband and high amplitude ultrasound field using pulsed laser excitation of a light-absorbing material via thermo-elastic expansion [7].…”