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341.
We present a single-shot incoherent light imaging method for simultaneously observing both amplitude and phase without any imaging optics, based on machine learning. In the proposed method, an object with a complex-amplitude field is illuminated with incoherent light and is captured by an image sensor with or without a coded aperture. The complex-amplitude field of the object is reconstructed from a single captured image using a state-of-the-art deep convolutional neural network, which is trained with a large number of input and output pairs. In experimental demonstrations, the proposed method was verified with a handwritten character database, and the effect of a coded aperture printed on an overhead projector film in the reconstruction was examined. Our method has advantages over conventional wavefront sensing techniques using incoherent light, namely simplification of the optical hardware and improved measurement speed. This study shows the importance and practical impact of machine learning techniques in various fields of optical sensing. 相似文献
342.
Takashi Ikeda Dr. Keishiro Tahara Dr. Ryoichi Ishimatsu Prof. Toshikazu Ono Dr. Luxia Cui Momoka Maeda Prof. Yoshiki Ozawa Prof. Masaaki Abe 《Angewandte Chemie (International ed. in English)》2023,62(21):e202301109
This study reports an effective peripheral decoration of organic donor-acceptor diads with B(C6F5)3 for stabilizing electrogenerated radical ions. By employing a common p-type organic semiconductor benzothienobenzothiophene (BTBT) as the donor, tetracoordinate boron complexes showed improved solution electrochemiluminescence (ECL) intensity, reaching a 156-fold increase compared to that of the parent diad. The unprecedented Lewis-pairing-induced ECL enhancement is attributed to the multiple roles of B(C6F5)3: 1) redistributing frontier orbitals, 2) facilitating electrochemical excitation, and 3) restricting molecular motions. Furthermore, B(C6F5)3 converted the molecular arrangement of BTBT from conventional 2D herringbones into 1D π-stacks. This robust, highly ordered columnar nanostructure allowed red-shifting of the crystalline film ECL with electrochemical doping through the electronic coupling pathways of BTBT. Our approach will facilitate the development of elaborate metal-free ECL systems. 相似文献
343.
Jinhua Chen Shin Hasegawa Hitoshi Ohashi Yasunari Maekawa Masaru Yoshida Ryoichi Katakai Norio Tsubokawa 《Macromolecular rapid communications》2002,23(2):141-144
The impedance effect on the ion transport of lithium chloride through temperature‐ and pH‐sensitive gel membranes was investigated. Both conductance and loss tangent show a relatively high value at temperatures near the lower critical solution temperature (14°C), followed by an abrupt drop with a further rise in temperature. The Figure shows an example of changes in absolute complex conductance (Y ), real conductance (G ), and imaginary conductance (B) for a poly(acryloyl‐L ‐proline methyl ester) gel membrane. 相似文献