Amorphous metal oxides (AMO) are a class of semiconducting materials that show promising application in optoelectronics because of their high carrier mobility and optical transparency. By alloying with other metallic species and regulating the oxygen vacancies, the carrier mobility, and the optical bandgap energy of AMOs can be modified. This customizability not only broadens the operating window of AMOs in optoelectronics but also further enables other applications, such as digital memory devices and thin-film-transistors. Typically, AMO thin films are obtained by conventional chemical or physical vapor deposition; however, these processes generally require undesirable toxic gas precursors, a vacuum environment, and a long processing time. Gallium-based liquid metals (LMs) – a class of metals that exist as liquid at or near room temperature – naturally forms an ultrathin layer of AMO (~3nm) on their surface under ambient conditions. Herein, we propose a method to harness this feature to continuously deposit gallium oxide (GaOx) and gallium indium oxide (GaInOx) traces with their host LMs at or near ambient conditions.
We present a multimodal imaging system that seamlessly integrates ultrasound imaging, photoacoustic imaging, and optical coherence tomography using a transparent ultrasonic transducer. We demonstrate the system’s use in imaging responses to mouse body in vivo.
Multi-modal imaging technique has significantly spotlighted since it can provide a variety of information by combining the complementary merits of several single-modal imaging. In particular, in order to compensate for each shortcoming and improve image quality, an integrated optical and ultrasonic imaging system is being actively researched. However, the non-transparency of the ultrasound transducer made it difficult to integrate the optical and ultrasound imaging system. In previous study, we introduced the transparent ultrasound transducer (TUT) and dual-modal photoacoustic imaging (PAI)/ultrasound imaging (USI) system using the TUT. In this study, we present the multi-modal imaging system integrated with PA, US and optical coherence tomography (OCT). OCT has the advantage of acquiring anatomical information at optical resolution under subsurface and transparent media. To explore the usefulness of the multi-modal imaging system, we have successfully performed in vivo animal experiments: 1) eye imaging experiments and 2) subcutaneous melanoma imaging. In PAI, blood vessels and melanoma are clearly visualized. In OCT, the morphological information in shallow depth are observed in detail. In USI, the melanoma boundary and surrounding tissues are clearly confirmed. These results show that TUT based multi-modal imaging system can serve as a comprehensive in various applications.
Ultrasound transducers, one of the most widely used sensors in the era of the fourth Industrial Revolution, have been recognized and used in a variety of industries including medical, automotive, and robotics. In particular, recent research has focused on the development of multi-mode imaging systems that combine ultrasound and optical imaging to improve the accuracy of information acquisition. Unfortunately, its efficient combination has been severely limited due to the inherent opacity of conventional ultrasound transducers. These limitations cause off-axes between the ultrasound (US) and optical signal paths, resulting in low signal-to-ratio and bulky system. This is especially a critical problem for a photoacoustic (PA) imaging system that requires the ultrasonic transducer to detect the photoacoustic signal. Here, we introduce a newly developed optically transparent ultrasound transducer (TUT) to overcome the limitation. We combined the developed TUT with an optical resolution photoacoustic microscopy (OR-PAM). Using a mouse, we successfully acquired in vivo PA and US images and confirmed the feasibility of the TUT and TUT integrated OR-PAM system.
Photoacoustic (PA) imaging is a biomedical imaging method that can provide both structural and functional information of living tissues beyond the optical diffusion limit by combining the concepts of conventional optical and ultrasound imaging methods. Although endogenous chromophores can be utilized to acquire PA images of biological tissues, exogenous contrast agents that absorb near-infrared (NIR) lights have been extensively explored to improve the contrast and penetration depth of PA images. Here, we demonstrate Bi2Se3 nanoplates, that strongly absorbs NIR lights, as a contrast agent for PA imaging. In particularly, the Bi2Se3 nanoplates produce relatively strong PA signals with an optical wavelength of 1064 nm, which has several advantages for deep tissue imaging including: (1) relatively low absorption by other intrinsic chromophores, (2) cost-effective light source using Nd:YAG laser, and (3) higher available energy than other NIR lights according to American National Standards Institute (ANSI) safety limit. We have investigated deep tissue imaging capability of the Bi2Se3 nanoplates by acquiring in vitro PA images of microtubes under chicken breast tissues. We have also acquired in vivo PA images of bladders, gastrointestinal tracts, and sentinel lymph nodes in mice after injection of the Bi2Se3 nanoplates to verify their applicability to a variety of biomedical research. The results show the promising potential of the Bi2Se3 nanoplates as a PA contrast agent for deep tissue imaging with an optical wavelength of 1064 nm.
The fabrication of stretchable devices has been explored via two approaches: wavy design of non-stretchable materials or elastomeric electronic materials. The first approach has been widely used, specifically led by Rogers group. The second approach requests stretchability of all the device components, hence there have been no reports on the fabrication of semiconducting polymer-based stretchable transistors due to the lack of stretchable active layer and dielectric. This presentation deals with the fabrication of an array of highly stretchable polymer transistors made entirely of stretchable components. The transistors were constructed of stretchable Au nanosheet electrodes, polyelectrolyte gel for the gate dielectric, metal nanowires for the circuit, and nanofibril-based stretchable channel materials. This talk will present the issues of the components regarding with the stretchability and mechanical performance.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.