Taichiro Fukui

Optical phased arrays (OPAs) are promising beam-steering devices for various applications such as light detection and ranging, optical projection, free-space optical communication, and optical switching. However, previously reported OPAs suffer from either an insufficient number of resolvable points, or complicated control requirements due to an extremely large number of phase shifters. To solve this issue, we introduce the non-redundant array (NRA) concept to the OPA devices. Based on this desi

Due to the unique nature of offering minimal invasiveness and high spatial resolution simultaneously, multimode fibers (MMFs) are receiving significant attention in bio-imaging applications. While a spatial light modulator is typically used for controlling the wavefront of the light emitted from the MMF, it makes the system slow, bulky, and expensive. To solve this problem, in this work, we demonstrate the use of a chip-scale integrated optical phased array (OPA) for imaging through an MMF. A si

Imaging through a multimode fiber (MMF) is a promising strategy for in vivo endoscopy due to its nature of simultaneously realizing high spatial resolution and minimal invasiveness. In MMF-based speckle imaging systems, a spatial light modulator (SLM) with a large number of pixels is commonly employed to enable independent controls of all the linearly polarized (LP) modes inside the MMF. Here, instead, we show that such an SLM can be replaced by a compact optical phased array (OPA) with a much s

We propose and numerically demonstrate novel imaging scheme using multimode fiber and integrated optical phased array. Thanks to modal dispersion and mixing inside fiber, clear images are obtained even with limited number of phase shifters.

We experimentally demonstrate single-pixel imaging using a multimode fiber attached with optical phased-array chip. By driving 128 integrated phase shifters, speckle patterns are generated from the fiber to realize clear imaging with 490 resolvable points.

An optical phased array (OPA) is a compact high-speed wavefront modulation device that is promising for next-generation optical sensing systems. In particular, speckle-based single-pixel imaging (SSPI) using OPA is an attractive scheme since precise tuning of optical phases is unnecessary. In this work, we present a comprehensive analysis of SSPI using an OPA with <i>N</i> phase shifters by comparing two classes of OPAs: uniformly spaced OPA (UOPA) and non-redundant OPA (NROPA). Through singular

We demonstrate that single-pixel imaging resolution of optical phased array can be enhanced by transmitting through a multimode fiber. Using only 128 phase shifters, &gt;1000 points are resolved, determined by the number of fiber modes.

As the first such line in the world, a 275 kV XLPE-insulated power cable transmission line was completed for the Nagoya substation of Electric Power Development Co., Ltd. (Japan) in June, 1979

We propose a surface-normal optical modulator using an InP high-contrast grating embedded with electro-optic polymer. The feasibility of broad-bandwidth (>40 GHz) and low-loss (<0.22 dB) modulation is numerically demonstrated, thanks to the high electron mobility and the small optical absorption of n- InP.

High-speed active metasurfaces enable spatiotemporal control of incident light within an ultra-thin layer, offering new possibilities for optical communication, computing, and sensing. However, a fundamental tradeoff between electrical conductivity and optical absorption of the material has hindered the realization of active metasurfaces that simultaneously achieve broad modulation bandwidth and low optical loss. Here, we experimentally demonstrate a high-speed active metasurface operating in th

This erratum corrects the error in Fig. 5 of our earlier paper [ Optica 8 , 1350 ( 2021 ) OPTIC8 2334-2536 10.1364/OPTICA.437453 ].