Interferometric detectors

2023 Optics Letters Vol. 48, Issue 10, pp. 2668-2671 Michael Nagli, Jürgen Koch, Yoav Hazan, Ahiad Levi, Orna Ternyak, Ludger Overmeyer, and Amir Rosenthal Abstract We present an all-optical focused ultrasound transducer with a sub-millimeter aperture and demonstrate its capability for high-resolution imaging of tissue ex vivo. The transducer is composed of a wideband silicon … Continue reading "High-resolution silicon photonics focused ultrasound transducer with a sub-millimeter aperture."Read More »

Biomedical Optics Express Vol. 13, Issue 12, pp. 6229-6244 (2022) © 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement Michael Nagli, Jürgen Koch, Yoav Hazan, Oleg Volodarsky, Resmi Ravi Kumar, Ahiad Levi, Evgeny Hahamovich, Orna Ternyak, Ludger Overmeyer, and Amir Rosenthal Abstract One of the main challenges in miniaturizing … Continue reading "Silicon-photonics focused ultrasound detector for minimally invasive optoacoustic imaging."Read More »

© 2022 Optica Publishing Group  Yoav Hazan, Michael Nagli, Ahiad Levi, and Amir Rosenthal Abstract Silicon photonics holds promise for a new generation of ultrasound-detection technology, based on optical resonators, with unparalleled miniaturization levels, sensitivities, and bandwidths, creating new possibilities for minimally invasive medical devices. While existing fabrication technologies are capable of producing dense resonator … Continue reading "Miniaturized ultrasound detector arrays in silicon photonics using pulse transmission amplitude monitoring."Read More »

© 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement© 2019 Optics Express, OSA publishing. AbstractUltrasound detection via optical resonators can achieve high levels of miniaturization and sensitivity as compared to piezoelectric detectors, but its scale-up from a single detector to an array is highly challenging. While the use of … Continue reading "Burst-mode pulse interferometry for enabling low-noise multi-channel optical detection of ultrasound."Read More »

© 2019 Optics Express, OSA publishing. AbstractIn optical detection of ultrasound, resonators with high Q-factors are often used to maximize sensitivity. However, in order to perform parallel interrogation, conventional interferometric techniques require an overlap between the spectra of all the resonators, which is difficult to achieve with high Q-factor resonators. In this paper, a new … Continue reading "Simultaneous multi-channel ultrasound detection via phase modulated pulse interferometry."Read More »

© 2019 IEEE Photonics Journal Impact Statement:This paper gives a solution to one of the fundamental limitations of silicon-photonics based ultrasound detectors: the low photo-elastic response of silicon and silica. By using a BCB over-cladding, 5-fold increase in the acoustic sensitivity is achieved. We additionally provide a detailed analysis of the sensing mechanism, quantifying the … Continue reading "Enhanced Sensitivity of Silicon-Photonics-Based Ultrasound Detection via BCB Coating."Read More »

© 2019 Optical Society of America The detection of ultrasound via optical resonators is conventionally performed by tuning a continuous-wave (CW) laser to the linear slope of the resonance and monitoring the intensity modulation at the resonator output. While intensity monitoring offers the advantage of simplicity, its sensitivity is often limited by the frequency noise … Continue reading "Noise reduction in resonator-based ultrasound sensors by using a CW laser and phase detection."Read More »

source: © 2018 Optical Society of America Coherence-restored pulse interferometry (CRPI) is a recently developed method for optical detection of ultrasound that achieves shot-noise-limited sensitivity and high dynamic range. In principle, the wideband source employed in CRPI may enable the interrogation of multiple detectors by using wavelength multiplexing. However, the noise-reduction scheme in CRPI has … Continue reading "Ultrasound detection via low-noise pulse interferometry using a free-space Fabry-Pérot"Read More »

source: © 2018 Light: Science & Applications Originally developed for diagnostic ultrasound imaging, piezoelectric transducers are the most widespread technology employed in optoacoustic (photoacoustic) signal detection. However, the detection requirements of optoacoustic sensing and imaging differ from those of conventional ultrasonography and lead to specifications not sufficiently addressed by piezoelectric detectors. Consequently, interest has shifted … Continue reading "Looking at sound: optoacoustics with all-optical ultrasound detection"Read More »

source: © 2018 Optical Society of America In the optical detection of ultrasound, resonators with high Q-factors are often used to maximize sensitivity. However, increasing the Q-factor of a resonator may reduce the linear range of the interrogation scheme, making it more susceptible to strong external perturbations and incapable of measuring strong acoustic signals. In … Continue reading "Passive-demodulation pulse interferometry for ultrasound detection with a high dynamic range"Read More »

source: © 2018 IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control Ultrasound detection is commonly performed by piezoelectric transducers that are optimized for a specific application. Since the piezoelectric technology is not configurable, transducers designed for one application may not be compatible with other applications. In addition, some designs of ultrasound transducers may be difficult … Continue reading "Ultrasound Detection Using Acoustic Apertures"Read More »

source: © 2017 Optical Society of America With recent advances in optical technology, interferometric sensing has grown into a highly versatile approach for ultrasound detection, with many interferometric detectors relying on optical waveguides to achieve high levels of sensitivity and miniaturization. In this Letter, we establish a practical model for assessing the sensitivity of silicon-photonics waveguides … Continue reading "Modeling the sensitivity dependence of silicon-photonics-based ultrasound detectors"Read More »

source: © 2017 Optical Society of America The addition of optoacoustic sensing to optical microscopy may supplement fluorescence contrast with label-free measurements of optical absorption, enhancing biological observation. However, the physical dimensions of many optoacoustic systems have restricted the implementation of hybrid optical and optoacoustic (O2A) microscopy to imaging thin samples in transmission mode or to … Continue reading "Fiber interferometer for hybrid optical and optoacoustic intravital microscopy"Read More »

source:© 2016 Optical Society of America Optical and optoacoustic (photoacoustic) microscopy have been recently joined in hybrid implementations that resolve extended tissue contrast compared to each modality alone. Nevertheless, the application of the hybrid technique is limited by the requirement to combine an optical objective with ultrasound detection collecting signal from the same micro-volume. We … Continue reading "All-optical optoacoustic microscope based on wideband pulse interferometry"Read More »

source: © 2016 Physical Review Letters The interaction of magnetic nanoparticles and electromagnetic fields can be determined through electrical signal induction in coils due to magnetization. However, the direct measurement of instant electromagnetic energy absorption by magnetic nanoparticles, as it relates to particle characterization or magnetic hyperthermia studies, has not been possible so far. We … Continue reading "Magnetoacoustic sensing of magnetic nanoparticles"Read More »