This is based on the lecture by the present author at the seminar on perovskite solar cell (PSC) organized by this society. PSC is surveyed from the viewpoint of dye sensitization in silver halide (AgX) photographic systems, which is the origin of dye-sensitized solar cells (DSC) and PSC. Analytical comparisons among them on their history, sensitizers and their interaction with substrates, efficiency of photo-induced formation of charge carriers, suppression of recombination between photoelectrons and positive holes, and technical skills have led to the proposals for further development of PSC including the characterization of the interface between perovskite materials and substrates.
Halide perovskites are a class of promising optoelectronic device materials for printable solar cells and light-emitting didoes. We discuss the fundamental optical properties of lead-free tin halide perovskites as organic-inorganic hybrid semiconductors.
This article reviews studies on optoelectronic properties of organic-inorganic perovskite by using time-resolved microwave conductivity（TRMC）technique. The content includes 1）direct observation of hole transfer process from a perovskite layer to a hole transport layer, 2）minutes-scale degradation of Sn-based perovskites upon exposure to the air, and 3）anomalous TRMC signal and dielectric behavior in Sn/Pb-mixed perovskite.
Images obtained through a ground-based telescope are blurred by atmospheric turbulence. Adaptive optics corrects the wavefront distortion caused by the atmospheric turbulence in real-time and realizes the diffraction-limited resolu tion of the telescope. This paper reviews adaptive optics systems for astronomy. First, the properties of atmospheric turbulence and the basic system configuration of adaptive optics systems are explained. Then, recent activities of adaptive optics development, especially that for small telescopes, are introduced.
In the ground-based astronomical observations, the wavefronts of lights from celestial objects are distorted by atmospheric turbulence of the Earth and therefore the images of the objects are blurred. We are developing an adaptive optics system, which compensates the distorted wavefronts in real-time and improves the spatial resolution of the image, for monitoring of the solar system planets. We present the purpose and overview of our adaptive optics system, the wavefront sensing with patterns on the surface of planet, the principal and overview of the multi-conjugate adaptive optics, and the status of our development.
Now that digital imaging has become mainstream from silver-halide photography, planetary imaging has made a dramatic evolution. Moving image shooting with high sensitivity / low noise image pickup device and high-resolution im age from the moving image with the spread of free software to extract, it became possible to shoot images of the exploration machine in the 1970 's even with a telescope used by amateurs. In this article, we introduce planetary imaging technology in amateurs and explain the technologies and possibilities that can be expected in the future.
We have developed an adaptive optical scanning laser ophthalmoscope (AO-SLO) that compensates for aberrations of the ocular and observes the retina with high resolution.Wide-field observation was realized by configuring all optical elements with refractive optics except for the beam splitter, wavefront compensating mirror and scanning mirror device. In addition, by configuring a scanning system that can change the scanning center position two-dimensionally, the maximum observation viewing angle 21 deg. and variable observation magnification and center position designation have been achieved. We confirmed the effectiveness and clinical applicability by photographing ocular diseases using AO-SLO, we introduce the performance of AO-SLO and some retinal images.
A particle therapy is a kind of radiotherapy using high-energy charged particle beams, which is capable of irradiating highly concentrated dose to tumors. Recently, since favorable treatment outcomes have been demonstrated, some tu mor sites begin to be covered by national health insurance in Japan. From the early stages of particle therapy, emulsion technology has been used to investigate it in important points. Greatly evolved today's emulsion technology is promising to contribute toward higher-precision particle therapy.