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In this study, an axicon metalens comprising a large central disc surrounded by nanoposts for energy harvesting in composite metal-oxide semiconductor sensors was designed, fabricated, and experimentally characterized. The main role of the central disc is focusing light; the nanoposts of various diameters deflect light to form a Bessel-like beam. The spatial distribution of the optical transmission was measured using micro-hyperspectral imaging. The axicon metalens concentrates the light to the sensitive area of the sensor and also harvests light from adjacent pixels. After adding an axicon metalens, the normalized peak transmission is up to 250% at λ = 700 nm as compared to a blank TiO2 film. The experimental results had fair agreement with the finite-difference-time-domain simulation. The ultra-broadband energy-harvesting performance of the sensor suggests that it could be applied in surveillance and Internet of Things applications.

By focusing on Asian American return narratives as a symbolic indicator of a shift in transpacific relations, this article attempts to address two questions: first, how will a focus on return experiences engage and reframe transpacific imperial geopolitics thatcreated and sustainedAsian American literature, and second, how will a focus on the “post/Cold War”rather than on globalization as a temporal frame challenge the transpacificimagination in American studiesas a cultural and economic narrative of immigration, integration,and salvationthat purports to transcend Cold War divisions.Thearticleanalyses Maxine Hong Kingston’s I Love a Broad Margin to My Life(2011) and Chang-rae Lee’s My Year Abroad(2021)to consider how post-1990s Asian American return narratives rearticulatecontemporary geopolitics. It will conclude with a reflection on the Orientalismof Asian Americanliteraturein the treacherous imaginaryof transpacific futures.

Current metalenses with large numerical apertures suffer from low efficiency. In this paper, we demonstrate a refractive-meta hybrid system consisting of a ball lens mainly providing the ray bending ability, and a meta-corrector to eliminate aberration of the optical system. Spatial frequency requirement of the meta-device is significantly reduced since system ray bending ability is mainly provided by refractive element. As a result, a large pixel liquid crystal spatial light modulator is sufficient to demonstrate the concept of meta-corrector for the refractive-meta hybrid system with a numerical aperture of 0.52. It is shown that the focal spot size can be significantly reduced from 322.07 μm to 0.636 μm for ray-tracing simulation, and 101.6 μm to 7.7 μm for measurement, as an appropriate phase distribution of the meta-corrector is added. We believe this pilot experiment can be applied to ball lenses and other optical lens-sets like cookie triplets as well.

This essay engages in border studies by articulating a “liminal island chain,” linking Okinawa, Taiwan, and Hong Kong, as a frontier of democracy in the rise of a new Cold War. Tracing the theoreti...

Tejaswini Niranjana is one of the important Indian cultural theorists. In Musicophilia in Mumbai: Performing Subjects and the Metropolitan Unconscious, she examines the emergence of Hindustani clas...

In honor of the late Masao Miyoshi, whose work has opened a transpacific dimension in Asian American studies, this essay first explores the notion of asymmetry, which is seminal to his critical vision, to build an analytical framework for understanding and evaluating the transnational impulses in recent Asian American literature. Using asymmetry as an analytical lens, it then provides a critical interpretation of Ruth Ozeki’s important novel A Tale for the Time Being (2013) to consider the intricate connections between Asia and North America that are embedded in the subterranean history of war, migration, resistance, and hope. By foregrounding the entangled, even complicit, transpacific transactions in Asian American narratives, this essay will not only speak to the complexities of the transpacific turn in Asian American studies but will also remind us of the importance of Miyoshi’s off-centered approach to questions of culture, history, and politics undeterred by borders.

Working through the entanglements of diaspora, national identification, and minority formation in the protracted aftermath of the Korean War, this article intends to take the dyadic subject of Nort...

In the twenty-first century, we are experiencing a new round of acceleration in the Anthropocene. On all fronts, art and education are facing new challenges and chances. On the one hand, the techno...

In this paper, an achromatic total internal reflection (TIR) prism set, consisting of two stacked prisms, is designed to reduce the lateral color aberration of a mini projector with light-emitting-diode (LED) light sources. Two different types of the prism set are proposed. Type 1 prism set is the first prism with a small Abbe number material stacked with the second prism with a large Abbe number material. By analyzing the optical properties of the proposed ATIR prism sets, we are able to choose an appropriate optical material combination of the prism set. For type 1 prism set, the corresponding lateral color aberration is 0. 65 μ m and the size is 2306 mm3. Nevertheless, the type 1 suffers from efficiency loss of 15.5%. For type 2 prism set, the corresponding lateral color aberration is 0. 61 μ m and the compact prism size is 3000 mm3. Although the size of type 2 prism set is larger than that of type 1, the efficiency loss can be as low as 1 %.

This chapter covers some of the key issues related to the use of heavily loaded reverberation chambers for OTA testing of wireless-device performance. It specifically adresses the cases where the communication signal is spread over a wide modulation bandwidth and must be demodulated and cases in which a particular PDP is to be replicated. Metrics used to characterize the chamber configuration, such as the reference power transfer function, spatial uniformity, isotropy, and chamber decay time, are not significantly different from those used in prior work of the EMC/EMI community. However, their application to the case where significant correlation exists between frequencies and spatial samples requires additional consideration.

In this study, the optical properties of a meta-GMR consisting of a metasurface stacked on a planar dielectric slab waveguide were theoretically investigated. Two different metasurfaces, namely chiral split-ring resonator dimer arrays with/without a rod-shaped antenna, were investigated and compared. Conventional GMR filters utilize gratings to couple the free-space electromagnetic field to the waveguide. The highly dispersive nature of grating leads to low angular tolerance. Here, the grating is replaced by metasurfaces. The metasurface unit cell can be regarded as a polarizable dipole that couples the free-space electromagnetic field to the waveguide and decouples the waveguide mode to the radiation modes. Based on the localized nature of the resonant metasurfaces, the metasurface/GMR hybrid mode exhibits a superior angular tolerance as compared with a conventional GMR filter. This study can open a new avenue to tailor the optical properties of GMR-based devices.

A 2MPixels@30fps 24b high-dynamic-range image processing chip is fabricated in a 16nm CMOS process with a core area of 5.69mm2. This LSI integrates multiple color-filter-array (RGGB, RGB-Ir, RCCC, RCCB, and Mono) image processing into a single chip. It contains 2,067k logic gates and 628.3kB internal SRAM. Moreover, it supports multiple-exposure sensor and up to 24b/color components fusion results to achieve 2.1 x dynamic range improvements compared to single exposure results. To efficiently deliver data to the external memory, tone mapping (TM) and data-bus compression and data-bus decompression (DCDD) techniques are developed to reduce external bandwidth by 69.1 %. For automotive applications, it completes real-time image processing with 4-exposure 1920×1080 @30fps and consumes 249mW (0.98nJ/pixel) of core power dissipation at 0.65V supply voltage operating at 250MHz. The chip features are summarized in Fig. 21.3.1.

In this paper, a tunable mid-infrared metasurface based on VO2 phase change material is proposed for temperature control. The proposed structure consisting of a VO2/SiO2/VO2 cavity supports a thermally switchable Fabry-Perot-like resonance mode at the transparency window of the atmosphere. Theoretically, the radiative cooling power density of the proposed metasurface can be switched to four-fold as the device temperature is below/above the phase change temperature of VO2. Besides radiative cooling, a passive temperature control application based on this huge cooling power switching ability is theoretically demonstrated. We believe the proposed device can be applied for small radiative cooling and temperature control applications.

In this paper we propose a Generalized Fiducial Inference inspired method for finding a robust consensus of several independently derived collection of confidence distributions (CDs) for a quantity of interest. The resulting fused CD is robust to the existence of potentially discrepant CDs in the collection. The method uses computationally efficient fiducial model averaging to obtain a robust consensus distribution without the need to eliminate discrepant CDs from the analysis. This work is motivated by a commonly occurring problem in inter-laboratory trials, where different national laboratories all measure the same unknown true value of a quantity and report their CDs. These CDs need to be fused to obtain a consensus CD for the quantity of interest. When some of the CDs appear to be discrepant, simply eliminating them from the analysis is often not an acceptable approach, particularly so in view of the fact that the true value being measured is not known and a discrepant result from a lab may be closer to the true value than the rest of the results. Additionally, eliminating one or more labs from the analysis can lead to political complications since all labs are regarded as equally competent. These considerations make the proposed method well suited for the task since no laboratory is explicitly eliminated from consideration. We report results of three simulation experiments showing that the proposed fiducial approach has better small sample properties than the currently used naive approaches. Finally, we apply the proposed method to obtain consensus CDs for gauge block calibration inter-laboratory trials and measurements of Newton’s constant of gravitation ( G ) by several laboratories.

In this paper, we propose a simple model, a combination of effective medium theory and the Jones matrix, to analyze the optical properties of a dielectric PB-phase metasurface with an arbitrary incident polarization state. The optical properties, such as the polarization conversion efficiency spectrum, rotation-angle-dependent phase modulation, and phasor diagram, shows a fair agreement with the finite difference time domain method results. This model provides a fast and sufficient accuracy compared to the time-consuming finite element methods. Moreover, the shortness of the proposed model is also discussed.

This study presents the design and fabrication of a dielectric metasurface with free-form phase distribution and with a large period unit cell. The dielectric metasurface is fabricated using i-line stepper, dry etching, and nanoimprint technology. The phase distribution of the meta-device is the combination of a blazed grating for deflection and an aspherical lens for eliminating the off-axis aberration. The optical measurement result shows the off-axis focusing spot is with loss aberration and the corresponding Strehl ratio is 0.34. The diffraction efficiency is around 2%. The low efficiency is mainly attributed to the rounding of the rectangular nanostructures during the pattern transfer and relatively thin thickness. Moreover, the polarization-dependency of this large period metasurface is also discussed.