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Related papers: FDTD-based Inverse Design enables f/0.27 flat Micr…

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Light-field imaging facilitates the miniaturization of 3D cameras while it requires the extension of the depth-of-field (DoF) for practical applications such as endoscopy and intraoral scanning. Here we report a light-field camera (LFC)…

Optics · Physics 2022-03-21 Jae-Myeong Kwon , Sang-In Bae , Taehan Kim , Jeong Kun Kim , Ki-Hun Jeong

We demonstrate numerically the diffraction-free propagation of sub-wavelength sized optical beams through simple elements built of metal-dielectric multilayers. The proposed metamaterial consists of silver and a high refractive index…

Optics · Physics 2011-06-07 R. Kotynski , T. Stefaniuk , A. Pastuszczak

Complex structure formation and fast focusing of light inside or through turbid media is a challenging task due to refractive index heterogeneity, random light scattering and speckle noise formation. Here, we have proposed a…

Optics · Physics 2023-10-11 Amit Kumar , Sarvesh Thakur , S. K. Biswas

We present a broadband and polarization-insensitive unidirectional imager that operates at the visible part of the spectrum, where image formation occurs in one direction while in the opposite direction, it is blocked. This approach is…

A major difficulty in applying computational design methods to nanophotonic devices is ensuring that the resulting designs are fabricable. Here, we describe a general inverse design algorithm for nanophotonic devices that directly…

Optics · Physics 2017-03-28 Alexander Y. Piggott , Jan Petykiewicz , Logan Su , Jelena Vučković

The diffractive nature of light has limited optics and photonics to operate at scales much larger than the wavelength of light. The major challenge in scaling-down integrated photonics is how to mold the light flow below diffraction-limit…

Optics · Physics 2007-12-27 Seunghoon Han , Yi Xiong , Dentcho Genov , Zhaowei Liu , Guy Bartal , Xiang Zhang

In this letter, we experimentally report an achromatic metalens (AML) operating over a continuous bandwidth in the visible. This is accomplished via dispersion engineering of dielectric phase shifters: titanium dioxide nanopillars tiled on…

Optics · Physics 2017-04-05 M. Khorasaninejad , Z. Shi , A. Y. Zhu , W. T. Chen , V. Sanjeev , A. Zaidi , F. Capasso

To improve the light extraction efficiency of organic light emitting diodes (OLEDs), we developed a novel substrate, i.e., a metamaterial based flat Moire micro-lens array formed using double nanoimprint, termed Mlens-array, consisting of a…

Optics · Physics 2023-02-02 Ji Qi , Wei Ding , Qi Zhang , Yuxuan Wang , Hao Chen , Stephen Y. Chou

Extended depth of focus (EDOF) lenses are important for various applications in computational imaging and microscopy. In addition to enabling novel functionalities, EDOF lenses can alleviate the need for stringent alignment requirements for…

Inverse design coupled with adjoint optimization is a powerful method to design on-chip nanophotonic devices with multi-wavelength and multi-mode optical functionalities. Although only two simulations are required in each iteration of this…

Applied Physics · Physics 2023-07-12 Ahmet Onur Dasdemir , Victor Minden , Emir Salih Magden

Metasurface-based lenses (metalenses) offer specific conceptual advantages compared to ordinary refractive lenses. For example, it is possible to tune the focal length of a metalens doublet by varying the relative angle between the two…

We report an ultrafast, parallel and beyond-the-master micro-patterning technique for ultrathin (30 nm-400 nm) non-absorbing polymer films by diffraction of a laser light through a two dimensional periodic aperture. The redistribution of…

Soft Condensed Matter · Physics 2011-01-28 Ankur Verma , Ashutosh Sharma , Giridhar U. Kulkarni

This paper presents a non-zoned discrete dielectric lens comprising two or three matching layers to reduce the 50-110 GHz frequency range reflections. Based on Chebyshev and binomial multi-section transformers, the designed models use…

Signal Processing · Electrical Eng. & Systems 2023-11-27 Juan Andrés Vásquez-Peralvo , José Manuel Fernández-González , Thomas Wong

Metalenses built up by artificial sub-wavelength nanostructures have shown the capability of realizing light focusing with miniature lens size. To date, most of the reported metalenses were patterned using electron beam lithography (EBL),…

Far-field characterization of small objects is severely constrained by the diffraction limit. Existing tools achieving sub-diffraction resolution often utilize point-by-point image reconstruction via scanning or labelling. Here, we present…

We demonstrate the back-end integration of broadband, high-NA GaN micro-lenses by micro-assembly onto non-native semiconductor substrates. We developed a highly parallel micro-fabrication process flow to suspend micron scale plano-convex…

We report a mid-infrared ring laser via fiber-to-waveguide hybrid integration enabled by directional couplers fabricated in fluoride glasses. Directional couplers were inscribed into fluoride glass using femtosecond laser direct writing,…

In this paper, we show by experiment that by covering a thin flat nonlinear lens on the sources, the sub-diffraction-limit observation can be achieved by measuring either the near-field distribution or the far-field radiation of the sources…

We report an easy-to-fabricate microcavity design to produce optically pumped high-$\beta$ quantum dot microlasers. Our cavity concept is based on a buried photonic-defect for tight lateral mode confinement in a quasi-planar microcavity…

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