Hemispherical Array Research Articles

Direct numerical simulation of turbulent heat transfer over surfaces with hemisphere protrusions

Direct numerical simulations (DNSs) of turbulent heat transfer over walls with regularly distributed hemispheric protrusions were conducted to explore how the arrangement and number density of hemispheres affect the turbulent heat transfer. For the rough walls, we considered eight rough surfaces, in which the number density, i.e., the number of hemispheres per unit area, and the distances between two neighboring hemispheres in the streamwise and spanwise directions were systematically varied. The friction Reynolds number was fixed at 660, and we considered an incompressible airflow with a Prandtl number of 0.71, neglecting the buoyancy effects. The results showed that the velocity roughness function strongly depends on the hemisphere arrangement and number density. The spanwise-aligned hemisphere array yields the larger velocity roughness function than its streamwise-aligned hemisphere counterpart, whereas the temperature roughness function depends only on number density. The Reynolds analogy factor decreases with increasing inner-scaled equivalent sand grain roughness, and the decreasing trend is weakly affected by the number density. We analyzed the momentum and heat transfer budgets and found that the pressure drag, which dominates the momentum transfer near the wall, is strongly affected by the hemisphere arrangement and number density. In contrast, the roughness-induced wall heat transfer term, which is the dominant contributor to near-wall heat transfer, depends only on the number density. This difference is the driving mechanism that causes dissimilar trends in momentum and heat transfer over walls with hemispheric protrusions.

Plasmonic hemispherical Ag nanoparticles on silicon substrate: A comprehensive study of optical properties

In this work, we demonstrate a comprehensive study of the optical properties of hemispherical Ag nanoparticles (AgNPs) on a single-crystal (c-Si) wafer. The fabricated method involves a galvanic displacement reaction of Ag on c-Si and annealing in oxygen atmosphere at 500 °C. Substrates with different morphological parameters of AgNPs were obtained by varying the volume ratio of Ag in the deposition solution. Using the quasinormal modes (QNMs) theory formalism, the localized surface plasmon resonance (LSPR) multipole positions were determined as a function of the AgNP size and incidence angle. Also, the effective field approximation and QNMs methods were used to calculate the specular reflectance of the disordered hemispherical array on c-Si. Thus, the experimentally obtained LSPR positions in the reflectance spectra were described. Finally, surface-enhanced Raman scattering (SERS) demonstrated reliable detection of brilliant green triphenylmethane dye (1 nM), methyl red dye (10 nM) and hemoglobin from bovine blood (1 mM). The dependence of the SERS enhancement factor on the LSPR position and the absorption band of the analyte was established, the maximum value of which was 1.1 × 107. In summary, this study suggests that the numerical and experimental investigation of the optical properties of hemispherical AgNPs on c-Si contributes to the field of optical sensing.

Multiplane Spectroscopic Whole‐Body Photoacoustic Computed Tomography of Small Animals In Vivo

AbstractTo understand complex biological process and disease progression, it is essential to comprehensively track biodynamics across entire organisms. The invaluable tracking tool, photoacoustic computed tomography (PACT), provides insights into structural, functional, and molecular aspects of living tissues. However, current small‐animal PACT systems suffer from low temporal/spatial resolution and a restricted field of view, and they are limited in the biological information they can provide, hindering research on whole‐body biodynamics. Here, it is demonstrated a continuous rotary‐scanning PACT system for rapid monitoring of various parameters within the relatively large torso of a small animal. In this PACT system, a hemispherical transducer array is continuously rotated at high speed, enabling a 3D scan of an entire mouse body in just 54 s, with a spatial resolution of 172–212 µm. The rapid rotary scanning allows us to not only image whole‐body structures but also to monitor pharmacokinetics and changes in hemoglobin oxygen saturation in living animals. This approach holds great promise for advancing the understanding of in vivo biological dynamics, opening up a new avenue of preclinical research in areas such as metabolic diseases and drug delivery.

Non-Invasive Blood-Brain Barrier Disruption Using Acoustic Holography With a Clinical Focused Ultrasound System.

Holographic methods can be used with phased array transducers to shape an ultrasound field. We tested a simple method to create holograms with a hemispherical 1024-element phased array transducer and explored how it could benefit ultrasound-mediated blood-brain barrier (BBB) disruption. With this method, individual acoustic simulations for each element of the transducer were simultaneously loaded into computer memory. Each element's phase was systematically modulated until the combined field matched a desired pattern. The method was evaluated with a 220 kHz transducer being tested clinically to enhance drug delivery via BBB disruption. The holograms were evaluated in a tissue-mimicking phantom and in vivo in experiments disrupting the BBB in rats and in a macaque. We also explored whether this approach could mitigate secondary reflections from the skull using simulations of transcranial focusing in clinical treatments of transcranial sonication for BBB disruption. This approach can enlarge the focal volume in a patient-specific manner and could reduce the number of sonication targets needed to disrupt large volumes, improve the homogeneity of the disruption, and improve our ability to detect microbubble activity in tissues with low vascular density. Simulations suggest that the method could also mitigate secondary reflections during transcranial sonication.

Investigation of Sonication Parameters for Large-Volume Focused Ultrasound-Mediated Blood-Brain Barrier Permeability Enhancement Using a Clinical-Prototype Hemispherical Phased Array.

Background/Objectives: Focused ultrasound (FUS) and microbubble (MB) exposure is a promising technique for targeted drug delivery to the brain; however, refinement of protocols suitable for large-volume treatments in a clinical setting remains underexplored. Methods: Here, the impacts of various sonication parameters on blood-brain barrier (BBB) permeability enhancement and tissue damage were explored in rabbits using a clinical-prototype hemispherical phased array developed in-house, with real-time 3D MB cavitation imaging for exposure calibration. Initial experiments revealed that continuous manual agitation of MBs during infusion resulted in greater gadolinium (Gd) extravasation compared to gravity drip infusion. Subsequent experiments used low-dose MB infusion with continuous agitation and a low burst repetition frequency (0.2 Hz) to mimic conditions amenable to long-duration clinical treatments. Results: Key sonication parameters-target level (proportional to peak negative pressure), number of bursts, and burst length-significantly affected BBB permeability enhancement, with all parameters displaying a positive relationship with relative Gd contrast enhancement (p < 0.01). Even at high levels of BBB permeability enhancement, tissue damage was minimal, with low occurrences of hypointensities on T2*-weighted MRI. When accounting for relative Gd contrast enhancement, burst length had a significant impact on red blood cell extravasation detected in histological sections, with 1 ms bursts producing significantly greater levels compared to 10 ms bursts (p = 0.03), potentially due to the higher pressure levels required to generate equal levels of BBB permeability enhancement. Additionally, albumin and IgG extravasation correlated strongly with relative Gd contrast enhancement across sonication parameters, suggesting that protein extravasation can be predicted from non-invasive imaging. Conclusions: These findings contribute to the development of safer and more effective clinical protocols for FUS + MB exposure, potentially improving the efficacy of the approach.

Feline eye-inspired artificial vision for enhanced camouflage breaking under diverse light conditions.

Biologically inspired artificial vision research has led to innovative robotic vision systems with low optical aberration, wide field of view, and compact form factor. However, challenges persist in object detection and recognition against complex backgrounds and varied lighting. Inspired by the feline eye, which features a vertically elongated pupil and tapetum lucidum, this study introduces an artificial vision system designed for superior object detection and recognition in a monocular framework. Using a slit-like elliptical aperture and a patterned metal reflector beneath a hemispherical silicon photodiode array, the system reduces excessive light and enhances photosensitivity. This design achieves clear focus under bright light and enhanced sensitivity in dim conditions. Theoretical and experimental analyses demonstrate the system's ability to filter redundant information and detect camouflaged objects in diverse lighting, representing a substantial advancement in monocular camera technology and the potential of biomimicry in optical innovations.

Novel approach to corrosion resistance and radiative cooling with biomimetic amorphous coatings

To address the application challenges of high-power-density electronic devices in harsh conditions, it is crucial to develop electric insulation materials that possess both corrosion resistance and excellent radiative cooling performance. In this study, inspired by the wrinkle morphology of the Camponotus ant with thermoregulation, a biomimetic amorphous coating composed of a hemispherical array was fabricated on aluminum alloy using plasma electrolytic oxidation (PEO) technology. This biomimetic microstructure is obtained by controlling the content of hexagonal boron nitride (h-BN) nanoparticles in the electrolyte, where the increase in current density at a later stage allows the transition of the porous coating to the hemispherical array. The effects of functional group vibration and rotation in combination with the hemispherical structure afford the biomimetic coating a high emissivity of 0.91 within the range of 3–14 μm, which reduces the LED temperature by 17.1 °C and achieves a cooling efficiency of 10.6 %. Meanwhile, with a resistivity of 5.15 × 1014 Ω∙cm and a dielectric strength of 29.9 V/μm, the coating can prevent current leakage, consequently improving the stability and reliability of electronic packaging materials. In addition, h-BN flakes in the biomimetic coating with almost defects free act as a protective barrier to enhance the corrosion resistance of the aluminum alloy. This approach offers a time-efficient and cost-effective route for the manufacture of multifunctional coatings with potential applications in electronic packaging.

Hemispherical Retina Emulated by Plasmonic Optoelectronic Memristors with All-Optical Modulation for Neuromorphic Stereo Vision.

Binocular stereo vision relies on imaging disparity between two hemispherical retinas, which is essential to acquire image information in three dimensional environment. Therefore, retinomorphic electronics with structural and functional similarities to biological eyes are always highly desired to develop stereo vision perception system. In this work, a hemispherical optoelectronic memristor array based on Ag-TiO2 nanoclusters/sodium alginate film is developed to realize binocular stereo vision. All-optical modulation induced by plasmonic thermal effect and optical excitation in Ag-TiO2 nanoclusters is exploited to realize in-pixel image sensing and storage. Wide field of view (FOV) and spatial angle detection are experimentally demonstrated owing to the device arrangement and incident-angle-dependent characteristics in hemispherical geometry. Furthermore, depth perception and motion detection based on binocular disparity have been realized by constructing two retinomorphic memristive arrays. The results demonstrated in this work provide a promising strategy to develop all-optically controlled memristor and promote the future development of binocular vision system with in-sensor architecture.

3D Multiparametric Photoacoustic Computed Tomography of Primary and Metastatic Tumors in Living Mice.

Photoacoustic computed tomography (PACT), an emerging imaging modality in preclinical cancer research, can provide multiparametric 3D information about structures, physiological functions, and pharmacokinetics. Here, we demonstrate the use of high-definition 3D multiparametric PACT imaging of both primary and metastatic tumors in living mice to noninvasively monitor angiogenesis, carcinogenesis, hypoxia, and pharmacokinetics. The high-definition PACT system with a 1024-element hemispherical ultrasound transducer array provides an isotropic spatial resolution of 380 μm, an effective volumetric field-of-view of 12.8 mm × 12.8 mm × 12.8 mm without scanning, and an acquisition time of <30 s for a whole mouse body. Initially, we monitor the structural progression of the tumor microenvironment (e.g., angiogenesis and vessel tortuosity) after tumor cell inoculation. Then, we analyze the change in oxygen saturation of the tumor during carcinogenesis, verifying induced hypoxia in the tumor's core region. Finally, the whole-body pharmacokinetics are photoacoustically imaged after intravenous injection of micelle-loaded IR780 dye, and the in vivo PACT results are validated in vivo and ex vivo by fluorescence imaging. By employing the premium PACT system and applying multiparametric analyses to subcutaneous primary tumors and metastatic liver tumors, we demonstrate that this PACT system can provide multiparametric analyses for comprehensive cancer research.

Cavitation monitoring, treatment strategy, and acoustic simulations of focused ultrasound blood-brain barrier disruption in patients with glioblastoma

PurposeWe report our experience disrupting the blood-brain barrier (BBB) to improve drug delivery in glioblastoma patients receiving temozolomide chemotherapy. The goals of this retrospective analysis were to compare MRI-based measures of BBB disruption and vascular damage to the exposure levels, acoustic emissions data, and acoustic simulations. We also simulated the cavitation detectors. MethodsMonthly BBB disruption (BBBD) was performed using a 220 kHz hemispherical phased array focused ultrasound system (Exablate Neuro, InSightec) and Definity microbubbles (Lantheus) over 38 sessions in nine patients. Exposure levels were actively controlled via the cavitation dose obtained by monitoring subharmonic acoustic emissions. The acoustic field and sensitivity profile of the cavitation detection system were simulated. Exposure levels and cavitation metrics were compared to the level of BBBD evident in contrast-enhanced MRI and to hypointense regions in T2*-weighted MRI. ResultsOur treatment strategy evolved from using a relatively high cavitation dose goal to a lower goal and longer sonication duration and ultimately resulted in BBBD across the treatment volume with minimal petechiae. Subsonication-level feedback control of the exposure using acoustic emissions also improved consistency. Simulations of the acoustic field suggest that reflections and standing waves appear when the focus is placed near the skull, but their effects can be mitigated with aberration correction. Simulating the cavitation detectors suggest variations in the sensitivity profile across the treatment volume and between patients. A correlation was observed with the cavitation dose, BBBD and petechial hemorrhage in 8/9 patients, but substantial variability was evident. Analysis of the cavitation spectra found that most bursts did not contain wideband emissions, a signature of inertial cavitation, but biggest contribution to the cavitation dose – the metric used to control the procedure – came from bursts with wideband emissions. ConclusionUsing a low subharmonic cavitation dose with a longer duration resulted in BBBD with minimal petechiae. The correlation between cavitation dose and outcomes demonstrates the benefits of feedback control based on acoustic emissions, although more work is needed to reduce variability. Acoustic simulations could improve focusing near the skull and inform our analysis of acoustic emissions. Monitoring additional frequency bands and improving the sensitivity of the cavitation detection could provide signatures of microbubble activity associated with BBB disruption that were undetected here and could improve our ability to achieve BBB disruption without vascular damage.

Broadband light absorption by a hemispherical concentric nanoshell array

Achieving highly efficient broadband absorption is an important research area in nanophotonics. In this paper, a novel method is proposed to design broadband near-perfect absorbers, consisting of a four-layer hemispherical concentric nanoshell array. The proposed nanostructure supports absorptivity exceeding 95% in the entire visible region, and the absorption bandwidth is determined by the interaction or ‘hybridization’ of the plasmons of the inner and outer metal-based nanoshells. Moreover, the designed absorber has wide-angle capability and is insensitive to polarization. The simple structure, as well as the stable absorption properties, suggests that such core–shell nanostructures can serve as a potential candidate for many applications such as solar energy harvesting, photo-detection, and emissivity control.

Artifact reduction in photoacoustic images by generating virtual dense array sensor from hemispheric sparse array sensor using deep learning

PurposeVascular distribution is important information for diagnosing diseases and supporting surgery. Photoacoustic imaging is a technology that can image blood vessels noninvasively and with high resolution. In photoacoustic imaging, a hemispherical array sensor is especially suitable for measuring blood vessels running in various directions. However, as a hemispherical array sensor, a sparse array sensor is often used due to technical and cost issues, which causes artifacts in photoacoustic images. Therefore, in this study, we reduce these artifacts using deep learning technology to generate signals of virtual dense array sensors.MethodsGenerating 2D virtual array sensor signals using a 3D convolutional neural network (CNN) requires huge computational costs and is impractical. Therefore, we installed virtual sensors between the real sensors along the spiral pattern in three different directions and used a 2D CNN to generate signals of the virtual sensors in each direction. Then we reconstructed a photoacoustic image using the signals from both the real sensors and the virtual sensors.ResultsWe evaluated the proposed method using simulation data and human palm measurement data. We found that these artifacts were significantly reduced in the images reconstructed using the proposed method, while the artifacts were strong in the images obtained only from the real sensor signals.ConclusionUsing the proposed method, we were able to significantly reduce artifacts, and as a result, it became possible to recognize deep blood vessels. In addition, the processing time of the proposed method was sufficiently applicable to clinical measurement.

Asymmetric optical transmission through periodic metallic hemisphere arrays on the transparent substrates

Asymmetric optical transmission is useful in various fields such as electromagnetic shielding, photovoltaic devices, and optical diodes owing to its directional selectivity for light. This work theoretically investigates asymmetric optical transmission by the periodic metallic hemisphere arrays on the transparent substrates. It is found that the formation of asymmetric optical transmission can be attributed to two aspects: the difference in the driving electric field and the first-order diffraction of the arrays. The maximum asymmetric optical transmission results from the match between the resonance wavelength of the arrays and the cut-off wavelength of the first-order diffraction inside the substrates. The bandwidth of asymmetric optical transmission is determined by the cut-off wavelength of the first-order diffraction inside the substrates. In addition, the effects of the structural parameters, including the radius of the metallic hemisphere and the material of the transparent substrate, on the maximum asymmetric optical transmission and the bandwidth are studied. This work provides design guidelines for practical devices to apply asymmetric optical transmission.

Performance and first measurements of the MAGIC stellar intensity interferometer

ABSTRACT In recent years, a new generation of optical intensity interferometers has emerged, leveraging the existing infrastructure of Imaging Atmospheric Cherenkov Telescopes (IACTs). The MAGIC telescopes host the MAGIC-SII system (Stellar Intensity Interferometer), implemented to investigate the feasibility and potential of this technique on IACTs. After the first successful measurements in 2019, the system was upgraded and now features a real-time, dead-time-free, 4-channel, GPU-based correlator. These hardware modifications allow seamless transitions between MAGIC’s standard very-high-energy gamma-ray observations and optical interferometry measurements within seconds. We establish the feasibility and potential of employing IACTs as competitive optical Intensity Interferometers with minimal hardware adjustments. The measurement of a total of 22 stellar diameters are reported, 9 corresponding to reference stars with previous comparable measurements, and 13 with no prior measurements. A prospective implementation involving telescopes from the forthcoming Cherenkov Telescope Array Observatory’s Northern hemisphere array, such as the first prototype of its Large-Sized Telescopes, LST-1, is technically viable. This integration would significantly enhance the sensitivity of the current system and broaden the UV-plane coverage. This advancement would enable the system to achieve competitive sensitivity with the current generation of long-baseline optical interferometers over blue wavelengths.

High Electric Field Enhancement Induced by Modal Coupling for a Plasmonic Dimer Array on a Metallic Film

A giant electric field on a subwavelength scale is highly beneficial for boosting the light–matter interaction. In this paper, we investigated a hybrid structure consisting of a hemispheric dimer array and a gold film and realized resonant mode coupling of the surface lattice resonance (SLR) and surface plasmon polariton (SPP). Mode coupling is demonstrated by observing anti-crossing in reflection spectra, which corresponds to Rabi splitting. Although the resonance coupling does not enter the strong coupling regime, an improved quality factor (Q~350) and stronger electric field enhancement in the gap region of the dimer (i.e., hot spot) in our hybrid structure are obtained compared to those of the single dimer or dimer array only. Remarkably, the magnitude of electric field enhancement over 500 can be accessible. Such high field enhancement makes our hybridized structure a versatile platform for the realization of ultra-sensitive biosensing, low-threshold nanolasing, low-power nonlinear optical devices, etc.

High-Sensitivity and Wide-Range Flexible Ionic Piezocapacitive Pressure Sensors with Porous Hemisphere Array Electrodes.

The development of high-performance flexible pressure sensors with porous hierarchical microstructures is limited by the complex and time-consuming preparation processes of porous hierarchical microstructures. In this study, a simple modified heat curing process was first proposed to achieve one-step preparation of porous hemispherical microstructures on a polydimethylsiloxane (PDMS) substrate. In this process, a laser-prepared template was used to form surface microstructures on PDMS film. Meanwhile, the thermal decomposition of glucose monohydrate additive during heat curing of PDMS led to the formation of porous structures within PDMS film. Further, based on the obtained PDMS/CNTs electrodes with porous hemisphere array and ionic polymer dielectric layers, high-performance ionic piezocapacitive sensors were realized. Under the synergistic effect of the low-stiffness porous hemisphere microstructure and the electric double layer of the ionic polymer film, the sensor based on an ionic polymer film with a 1:0.75 ratio of P(VDF-HFP):[EMIM][TFSI] not only achieves a sensitivity of up to 106.27 kPa-1 below 3 kPa, but also has a wide measurement range of over 400 kPa, which has obvious advantages in existing flexible piezocapacitive sensors. The rapid response time of 110 s and the good stability of 2300 cycles of the sensor further elucidate its practicality. The application of the sensor in pulse monitoring, speech recognition, and detection of multiple dynamic loads verifies its excellent sensing performance. In short, the proposed heat curing process can simultaneously form porous structures and surface microstructures on PDMS films, greatly simplifying the preparation process of porous hierarchical microstructures and providing a simple and feasible way to obtain high-performance flexible pressure sensors.

A Flexible Surgical Robot with Hemispherical Magnet Array Steering and Embedded Piezoelectric Beacon for Ultrasonic Position Sensing

This article proposes a flexible surgical robot featuring strong magnetic steering achieved by a hemispherical magnet array actuation, and high‐accuracy ultrasonic position sensing achieved by a beacon total focusing method (b‐TFM). The hemispherical magnet array with magnetic focusing is described and its array parameters are optimized through finite element analysis to increase the magnetic field for actuation. The magnetic field strength at 100 mm for the array with the same mass as the cylindrical magnet is about 1.8 times higher than that of the cylindrical magnet. Using the magnet array actuation, the flexible robot exhibits the capability of agile steering to navigate along a predefined trajectory. In addition, a 1 mm × 1 mm lead zirconate titanate (PZT) patch is embedded into the tip of the flexible robot as a beacon for b‐TFM ultrasonic imaging to detect the position of the robot. Therefore, the entire navigation process can be executed under the supervision of the ultrasonic position sensing system, and the maximum error is 0.8 mm when the steering radius is 100 mm.

A Transmit-Receive Phased Array for Microbubble-Mediated Focused Ultrasound Brain Therapy in Small Animals.

This study aimed to design, construct, and evaluate a dual-mode phased array for MB-mediated FUS brain therapy in small animals. A 256-element sparse hemispherical array (100 mm diameter) was fabricated by installing 128 PZT cylinder transmitters (f0 = 1.16 MHz) and 128 broadband PVDF receivers within a 3D-printed scaffold. The transmit array's focal size at the geometric focus was 0.8 mm × 0.8 mm × 1.7 mm, with a 31 mm/27 mm (lateral/axial) steering range. The receive array's point spread function was 0.6 mm × 0.6 mm × 1.5 mm (1.16 MHz source) at the geometric focus, and sources were localized up to 30 mm/16 mm (lateral/axial) from geometric focus. The array was able to spatially map MB cloud activity in 3D throughout a vessel-mimicking phantom at sub-, ultra-, and second-harmonic frequencies. Preliminary in-vivo work demonstrated its ability to induce localized BBB permeability changes under 3D sub-harmonic MB imaging feedback in a mouse model. Small form factor transmit-receive phased arrays enable acoustic imaging-controlled FUS and MB-mediated brain therapies with high targeting precision required for rodent studies. Dual-mode phased arrays dedicated for small animal use will facilitate high-throughput studies of FUS-mediated BBB permeability enhancement to explore novel therapeutic strategies for future clinical application.

Surface Microstructure Engineering in MAPbBr3 Microsheets for Performance-Enhanced Photodetectors.

Metal halide-perovskite-based photodetectors have recently emerged as a class of promising optoelectronic devices in various fields. Meanwhile, nano/microstructuring perovskite-based photodetectors are a facile integration with complementary metal-oxide semiconductors for miniaturized imaging systems. However, there are still challenges to be overcome in reducing the losses caused by light reflection on the surface of microstructural perovskites. In this work, surface microstructure engineering is employed in MAPbBr3 microsheets for reducing light reflection and improving light absorption, resulting in high-performance perovskite photodetectors. MAPbBr3 microsheets, which possess different surface morphologies of flat, upright hemisphere arrays and inverted hemisphere arrays (IHAs), are fabricated by a simple microstructure template-assisted space confinement process. The light absorption capacity of IHA MAPbBr3 is significantly higher than that of the other two structures. Hence, IHA photodetectors with excellent figures of merit, including low dark current, decent responsivity, and fast speed, are achieved. Furthermore, the noise of the IHA photodetectors is only ∼10-13 A/, which results in the superior sensitivity for weak light detection with a specific detectivity up to 1011 Jones. Our results demonstrate that surface engineering is a simple, low-cost, yet effective approach to improve the performance of nano-/micro-optoelectronic devices.

Highly Sensitive Flexible Capacitive Pressure Sensor with Porous Hierarchical Structure Realized by a Microwave Curing Method

The introduction of porous hierarchical microstructures effectively improves the sensitivity of flexible pressure sensors. However, it is difficult to achieve porous hierarchical microstructures for pressure sensors through inexpensive, efficient, and simple preparation methods. Herein, a hemispherical array with porous hierarchical microstructure is prepared on polydimethylsiloxane substrate using a simple one‐step microwave curing process with glucose as porogen. Furthermore, the flexible electrode based on the polydimethylsiloxane substrate is combined with an ionic liquid polymeric gel membrane to obtain a flexible capacitive pressure sensor. Thanks to the deformability of porous hierarchical microstructure and the double‐dielectric layer effect of ionic liquid polymeric gel membrane, the sensor displays an ultrahigh sensitivity of 131.21 kPa−1 within 0–1 kPa. Meanwhile, the sensor has short response time, excellent dynamic loading stability, as well as excellent long‐term stability (&gt;3000 cycles). In application testing, the sensor effectively monitors various physiological activities like pulse, breathe, speech, and swallowing, demonstrating its good prospects in the field of health electronics. Most importantly, the proposed microwave curing method can realize the preparation of porous hierarchical structure on flexible substrate through a one‐step process, which offers a fresh way for the economical, green, and efficient preparation of high‐sensitivity capacitive pressure sensors.