研究者データベース

澁川 敦史(シブカワ アツシ)
電子科学研究所 生命科学研究部門
准教授

基本情報

所属

  • 電子科学研究所 生命科学研究部門

職名

  • 准教授

学位

  • 博士(情報科学)(2014年03月 北海道大学)

J-Global ID

研究キーワード

  • ホログラフィ,光波面制御,光遺伝学,ロドプシン   

研究分野

  • ものづくり技術(機械・電気電子・化学工学) / 電子デバイス、電子機器

研究活動情報

論文

  • Keiichi Kojima, Natsuki Miyoshi, Atsushi Shibukawa, Srikanta Chowdhury, Masaki Tsujimura, Tomoyasu Noji, Hiroshi Ishikita, Akihiro Yamanaka, Yuki Sudo
    The Journal of Physical Chemistry Letters 11 15 6214 - 6218 2020年07月22日 [査読有り]
  • The Unlimited Potential of Microbial Rhodopsins as Optical Tools
    K. Kojima, A. Shibukawa, Y. Sudo
    Biochemistry 59 3 218 - 229 2019年12月 [査読有り][招待有り]
  • Quantitation of the neural silencing activity of anion channelrhodopsins in Caenorhabditis elegans and their applicability for long-term illumination
    T. Yamanashi, M. Maki, K. Kojima, A. Shibukawa, T. Tsukamoto, S. Chowdhury, A. Yamanaka, S. Takagi, Y. Sudo
    Scientific Reports 9 7863 2019年05月 [査読有り][通常論文]
  • Photochemical Characterization of a New Heliorhodopsin from the Gram-Negative Eubacterium Bellilinea caldifistulae (BcHeR) and Comparison with Heliorhodopsin-48C12
    A. Shibukawa, K. Kojima, Y. Nakajima, Y. Nishimura, S. Yoshizawa, Y. Sudo
    Biochemistry 58 26 2934 - 2943 2019年05月 [査読有り][通常論文]
  • Virtual phase conjugation based optical tomography for single-shot three-dimensional imaging
    Yuta Goto, Atsushi Okamoto, Atsushi Shibukawa, Kazuhisa Ogawa, Akihisa Tomita
    Optics Express 26 3779 - 3790 2018年02月 [査読有り][通常論文]
  • Mooseok Jang†, Yu Horie†, Atsushi Shibukawa†, Joshua Brake, Yan Liu, Seyedeh Mahsa Kamali, Amir Arbabi, HaowenRuan, Andrei Faraon, Changhuei Yang
    Nature Photonics 12 84 - 90 2018年02月 [査読有り][通常論文]
  • Edward Haojiang Zhou, Atsushi Shibukawa, Joshua Brake, Haowen Ruan, Changhuei Yang
    OPTICA 3 10 1107 - 1113 2016年10月 [査読有り][通常論文]
     
    Imaging of a weak target hidden behind a scattering medium can be significantly confounded by glare. We report a method, termed coherence gated negation (CGN), that uses destructive optical interference to suppress glare and allow improved imaging of a weak target. As a demonstration, we show that by permuting through a set range of amplitude and phase values for a reference beam interfering with the optical field from the glare and target reflection, we can suppress glare by an order of magnitude, even when the optical wavefront is highly disordered. This strategy significantly departs from conventional coherence gating methods in that CGN actively "gates out" the unwanted optical contributions while conventional methods "gate in" the target optical signal. We further show that the CGN method can outperform conventional coherence gating image quality in certain scenarios by more effectively rejecting unwanted optical contributions. (C) 2016 Optical Society of America
  • Nicolino Stasio†, Atsushi Shibukawa†, Ioannis N, Papadopoulos, Salma Farahi, Olivier Simandoux, Jean-Pierre Huignard, Emmanuel Bossy, Christophe Moser, Demetri Psaltis
    BIOMEDICAL OPTICS EXPRESS 6 12 4619 - 4631 2015年12月 [査読有り][通常論文]
     
    In this paper we demonstrate the enhancement of the sensing capabilities of glass capillaries. We exploit their properties as optical and acoustic waveguides to transform them potentially into high resolution minimally invasive endoscopic devices. We show two possible applications of silica capillary waveguides demonstrating fluorescence and optical-resolution photoacoustic imaging using a single 330 mu m-thick silica capillary. A nanosecond pulsed laser is focused and scanned in front of a capillary by digital phase conjugation through the silica annular ring of the capillary, used as an optical waveguide. We demonstrate optical-resolution photoacoustic images of a 30 mu m-thick nylon thread using the water-filled core of the same capillary as an acoustic waveguide, resulting in a fully passive endoscopic device. Moreover, fluorescence images of 1.5 mu m beads are obtained collecting the fluorescence signal through the optical waveguide. This kind of silica-capillary waveguide together with wavefront shaping techniques such as digital phase conjugation, paves the way to minimally invasive multi-modal endoscopy. (C) 2015 Optical Society of America
  • Jin Nozawa, Atsushi Okamoto, Atsushi Shibukawa, Masanori Takabayashi, Akihisa Tomita
    APPLIED OPTICS 54 29 8644 - 8652 2015年10月 [査読有り][通常論文]
     
    We propose a two-channel holographic diversity interferometer (2ch-HDI) system for single-shot and highly accurate measurements of complex amplitude fields with a simple optical setup. In this method, two phase-shifted interference patterns are generated, without requiring a phase-shifting device, by entering a circularly polarized reference beam into a polarizing beam splitter, and the resulting patterns are captured simultaneously using two image sensors. However, differences in the intensity distributions of the two image sensors may lead to serious measurement errors. Thus, we also develop a two-channel algorithm optimized for the 2ch-HDI to compensate for these differences. Simulation results show that this algorithm can compensate for such differences in the intensity distributions in the two image sensors. Experimental results confirm that the combination of the 2ch-HDI and the calculation algorithm significantly enhances measurement accuracy. (c) 2015 Optical Society of America
  • Kaori Nishimaki, Atsushi Okamoto, Atsushi Shibukawa, Akihisa Tomita, Yoshihisa Takayama, Masatoshi Bunsen
    JAPANESE JOURNAL OF APPLIED PHYSICS 53 8 08MB13  2014年07月 [査読有り][通常論文]
     
    In optical intersatellite communication, the background light consisting mainly of sunlight decrease transmission rate with increasing bit error. A spatial filtering system using a double-phase-conjugate mirror (DPCM) and a phase plate is proposed to block the background light, which cannot be filtered out by using wavelength filters, polarization filters, or dousers. In this system, the effect of wavefront distortion caused by the phase plate and the compensation effect of the distortion by phase conjugate light from the DPCM are effectively combined for spatially separating signal light and background light. We demonstrated the reduction of the background light by the proposed system and optimized the phase plate for maximizing this reduction effect. As a result, it was clarified that the transmission rate can be drastically improved up to 11-fold. (C) 2014 The Japan Society of Applied Physics
  • Kaori Nishimaki, Atsushi Okamoto, Atsushi Shibukawa, Masanori Takabayashi, Akihisa Tomita, Yoshihisa Takayama
    OPTICAL REVIEW 21 3 415 - 424 2014年05月 [査読有り][通常論文]
     
    A double phase conjugate mirror (DPCM), created by two mutually incoherent beams entering photorefractive nonlinear materials, can generate a phase conjugate beam whose reflectivity may be greater than 100%. Even though the conditions of the incident beams are changed, the DPCM can be dynamically reconfigured by using a Sn2P2S6 crystal with a high response speed. These features of the DPCM are advantageous, particularly in an optical inter-satellite communication system. In particular, use of the phase conjugate beam from the DPCM offers wavefront compensation and amplification in satellite communication. In addition, the dynamically reconfigurable DPCM using a Sn2P2S6 crystal relaxes the acquisition accuracy of the signal beam in the system. In this study, the temporal and spatial operating characteristics of the DPCM using a Sn2P2S6 crystal were first clarified. Next, an inter-satellite system based on the DPCM was proposed, and it was demonstrated that our system significantly improves the tolerance of the acquisition accuracy and tracking time. (C) 2014 The Japan Society of Applied Physics
  • Atsushi Shibukawa, Atsushi Okamoto, Yuta Goto, Satoshi Honma, Akihisa Tomita
    OPTICS EXPRESS 22 10 11918 - 11929 2014年05月 [査読有り][通常論文]
     
    In a conventional digital phase conjugation system, only the phase of an input light is time-reversed. This deteriorates phase conjugation fidelity and restricts application fields to specific cases only when the input light has uniformly-distributed scattered wavefront. To overcome these difficulties, we present a digital phase conjugate mirror based on parallel alignment of two phase-only spatial light modulators (SLMs), in which both amplitude and phase of the input light can be time-reversed. Experimental result showed that, in the phase conjugation through a holographic diffuser with diffusion angle of 0.5 degree, background noises decrease to 65% by our digital phase conjugation mirror. (C)2014 Optical Society of America
  • 光複素振幅制御技術を用いた超高密度ホログラフィックメモリに関する研究
    渋川敦史
    北海道大学 2014年03月 [査読有り][招待有り]
  • Atsushi Shibukawa, Atsushi Okamoto, Masanori Takabayashi, Akihisa Tomita
    OPTICS EXPRESS 22 4 3968 - 3982 2014年02月 [査読有り][通常論文]
     
    We propose a spatial cross modulation method using a random diffuser and a phase-only spatial light modulator (SLM), by which arbitrary complex-amplitude fields can be generated with higher spatial resolution and diffraction efficiency than off-axis and double-phase computer-generated holograms. Our method encodes the original complex object as a phase-only diffusion image by scattering the complex object using a random diffuser. In addition, all incoming light to the SLM is consumed for a single diffraction order, making a diffraction efficiency of more than 90% possible. This method can be applied for holographic data storage, three-dimensional displays, and other such applications. (C) 2014 Optical Society of America
  • Keisuke Zukeran, Atsushi Okamoto, Masanori Takabayashi, Atsushi Shibukawa, Kunihiro Sato, Akihisa Tomita
    JAPANESE JOURNAL OF APPLIED PHYSICS 52 9 09LD13  2013年09月 [査読有り][通常論文]
     
    We proposed a double-referential holography (DRH) that allows phase-detection without external additional beams. In the DRH, phantom beams, prepared in the same optical path as signal beams and preliminary multiplexed in a recording medium along with the signal, are used to produce interference fringes on an imager for converting a phase into an intensity distribution. The DRH enables stable and high-accuracy phase detection independent of the fluctuations and vibrations of the optical system owing to medium shift and temperature variation. Besides, the collinear arrangement of the signal and phantom beams leads to the compactness of the optical data storage system. We conducted an experiment using binary phase modulation signals for verifying the DRH operation. In addition, 38-level spatial quadrature amplitude modulation signals were successfully reproduced with the DRH by numerical simulation. Furthermore, we verified that the distributed phase-shifting method moderates the dynamic range consumption for the exposure of phantom beams. (c) 2013 The Japan Society of Applied Physics
  • Atsushi Shibukawa, Atsushi Okamoto, Yuta Wakayama, Akihisa Tomita, Hisatoshi Funakoshi, Kunihiro Sato
    JAPANESE JOURNAL OF APPLIED PHYSICS 52 9 09LD03  2013年09月 [査読有り][通常論文]
     
    To suppress interpage crosstalk that strongly restricts holographic data storage capacity, a digital image diffusion technique was proposed. In this technique, signal and crosstalk components are separated from the propagation angle difference produced by using a random diffuser and the nature of phase conjugate lights. The most attractive feature of the technique is that crosstalk suppression can be conducted while mostly keeping the conventional holographic data storage system unchanged by integrating optical processing and digital processing effectively. The connection between the two types of processing is realized by using two spatial light modulators for complex amplitude generation and phase detection methods for complex amplitude measurement. The simulation results showed that the proposed technique could increase the recording density 5.5-fold and reduce the shift pitch by a factor of 5 in comparison with conventional multiplexing methods when the diffusion angle of the diffuser is 10 degrees. (c) 2013 The Japan Society of Applied Physics
  • 多層化コリニアホログラムによる超高密度記録
    岡本淳, 渋川敦史
    光学 40 11 591 - 593 2011年11月 [査読無し][招待有り]
  • Atsushi Shibukawa, Atsushi Okamoto, Akihisa Tomita, Masanori Takabayashi, Kunihiro Sato
    JAPANESE JOURNAL OF APPLIED PHYSICS 50 9 09ME10  2011年09月 [査読有り][通常論文]
     
    We proposed a new multilayer collinear holographic memory (MCHM) with a movable random phase mask that can act as an interlayer crosstalk reducer. First, to clarify the feasibility of our proposed device, we showed that it has an extremely sharp shift selectivity along the thickness direction of medium of nearly 5.0 mu m when the numerical aperture of the objective lens is 0.60. Next, we demonstrated that the utilization of the movable random phase mask can suppress interlayer crosstalk sufficiently, resulting in the improvement in the quality of reconstructed signals. Moreover, we revealed that the MCHM, in which the parallel use of a multilayered technique and collinear shift multiplexing is performed, brings out the medium potential sufficiently in terms of signal to noise ratio and medium dynamic range consumption. Finally, we verified that the MCHM can achieve a nearly 2 times larger data density at least compared with a conventional collinear holographic memory. (C) 2011 The Japan Society of Applied Physics

特許

  • 特開WO/2018/195309:HIGHLY SCATTERING METASURFACE PHASE MASKS FOR COMPLEX WAVEFRONT ENGINEERING  2018年10月25日
    JANG, Mooseok, US HORIE, Yu, US SHIBUKAWA, Atsushi, US FARAON, Andrei, US YANG, Changhuei, US
  • 特許第6230047号:複素振幅画像表示方法、散乱位相画像生成装置および散乱位相画像生成方法    2017年10月27日
    岡本淳, 渋川敦史, 後藤優太
  • 特許第6029167号:ノイズ除去方法およびノイズ除去装置、記録再生方法および記録再生装置、ならびに、画像計測方法および画像計測装置    2016年10月28日
    岡本 淳, 渋川 敦史, 若山 雄太
  • 特開WO2015068834:複素振幅像生成装置および複素振幅像生成方法  2015年05月14日
    岡本 淳, 渋川敦史
  • 特開WO/2013/008453:ホログラフィックメモリの記録方法および再生方法ならびにホログラフィックメモリの記録装置および再生装置  2013年01月17日
    岡本淳, 瑞慶覧圭佑, 高林正典, 渋川敦史


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