Inorganic ferroelectric materials of Ba_1-xPb_xTiO₃ powders were synthesized by firing and their application to the ferroelectric imaging was conducted. Firstly, the pellets of their solid solutions were prepared and the required material properties for the ferroelectric imaging were investigated. The investigation revealed that the ferroelectrics with lower dielectric constant and higher resistivity were poled by corona charging to the higher extent, leading to the development of the higher pyroelectric surface potential. The best suited derivative in the present system was obtained at x = 0.25, Ba_0.75Pb_0.25TiO₃ (relative dielectric constant = 420, resistivity = 8.0×10¹³Ωcm), and its pyroelectric potentials were -0.23 and +0.25V/μm for the positive and negative poling treatments, respectively.
Secondly, the more advanced materials, the composite films of Ba_0.75Pb_0.25TiO₃ with polyvinylbutyral (PVB), were prepared and their feasibility to be used as a ferroelectric imaging medium was investigated. As a result, the composites were found to have ferroelectric and pyroelectric properties superior to those of the corresponding solid solutions, and developed higher pyroelectric potentials: the pyroelectric potentials of -1.2 and +1.6V/μm for the positive and negative poling treatments, respectively, were obtained when the Ba_0.75Pb_0.25TiO₃ was prepared by firing (1000°C, 3h)twice or three times and the resultant composite film (ca. 80μm thick)was heated at 140°C. The charged film attracted toner particles according to the positional distribution of the pyroelectric potentials to give visible images.

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Recently the application of JPEG2000 is studied extensively. Motion-JPEG2000 is image coding/decoding algorithm for motion picture based on JPEG2000. Degradation by Motion-JPEG2000 is investigated and its improvement is proposed. Median and averaging filter over time-space domain with threshold is applied to degraded picture. Concerning 4 typical motion pictures of animations and natural images, the threshold dependence on image quality is evaluated subjectively. The median filter with the threshold is found to be effective for image quality improvement.

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We make experiments charging a polyethylene-terephthalate sheet with a metal roller, and observe discharges that occur in the gap between the roller and the sheet. The pattern of the charge distribution, made visible by sprinkling color-powders onto the sheet surface after the electrification, appears when applied voltage (DC) to the roller exceed a threshold value. This threshold coincides with threshold of appearance of the discharge pulses. The threshold is independent of the polarity of applied voltage, but the shapes of the patterns depends upon the polarity. The pattern is star-like with positive voltage, and round with negative electrification. Length of the discharge light along the sheet is approximately same as the spatial repetition distance of the charge pattern. Therefore the non-uniform electrification is ascribed to the discharges. We can predict the threshold voltage calculating the voltage across the gap using the partial capacitance model and Paschen's law.

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A basic idea for embedding the spectral pallet in RGB pixels is proposed. A tri-color image is converted into the spectral image, whose pixel is replaced by the spectral reflectance having the closest colorimetric value to that of pixel by looking up the spectral color palette. SVD representation was very useful for the spectral image compression. We applied SVD for rearranged 36 pixels×36 spectra in local sub-divided block image, so that we could make use of strong correlations in both space and spectral distributions. The spectral image could be very well reproduced from a small number of singular values by SVD. Although a created image has not the real world spectra but palette-based pseudo-spectra, the proposed method could be applied to estimate how much the huge spectral image data could be compressed, and to simulate the color appearances for a given set of ink and paper media under the various light sources. The paper discusses the color reproducibility by SVD compression and introduces the estimated color appearances for inkjet prints under different fluorescent lamps.

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A test method for estimating the life expectancy of an optical media storing archival digital information has been discussed. In this report, a commercial phase change (PC) media was examined by an accelerated life test using Arrehnius method based on the effects of temperature and relative humidity, and a long-term storage test under general room condition. The life expectancy in a PC media was evaluated by measurement of byte error rate (BER). The experimental results were confirmed that life expectancy of a PC media is deemed to be sufficiently long (about 50∼100 years), and that life expectancy depends on the initial condition of recorded layer and recording condition such as recording speed.

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The resolution in a human vision should not be uniform, when considering the distribution of the cone cells on a retina. However, the details of resolution distribution has not clarified yet: it remains unclear what kind of images are formed on a virtual screen in a brain. This study aims to clarify how images are formed on the virtual screen in the brain. We expect this kind of study can indicate minimum image set necessary for non-degraded image recognition. Objective test were carried out to clarify the resolution distribution in a human vision: eye mark tracks were recorded in the task of searching a target pattern from among a pattern array projected on a screen. An resolution distribution was obtained using measured result of these eye marks. Subjective tests were carried out in order to confirm human sensitivity to degraded images with decreased chroma value in circumferential area. The subjects were asked to choose their impression on the degree of image degradation from five levels of answers. Both the distributions of the sensitivity to chroma and that of the resolution have shown good similarity to the distribution of cone cells on a retina. The actual image in the brain were estimated from these distributions. Finally, degraded images were prepared according to the distribution carbs of resolution and chroma sensitibity obtained from former measurements and used for subjective evaluations. These degraded images were proven not to be annoying as expected.

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A new technology combined with metal nano-particles and a printing technology cultivated in the electronics industry has been developed, which innovates a traditional manufacturing process of electronics packaging.
Such a new semiconductor packaging technology is being achieved that metal nano-particles are used as printing inks and applied them on PC or flexible PC substrates through printer or screen processes. In the near future, not only metallic circuits, but also passive components will be possibly printed on PC substrates.
These technologies are capable of shorter delivery and have lower environmental impacts on manufacturing and have potential for bearing new applications utilizing of characteristics of metal nano-particles.

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We review recent advances in ultrafast laser technology as applied to the field of ultra-fine materials processing. Ultrafast lasers are a class of lasers that produce pulse widths of from picoseconds to femtoseconds. The most important characteristics of ultrafast laser-matter interaction include precise ablation threshold and absence of heat diffusion into the material during laser irradiation, both of which are due to the short temporal duration of the laser pulse. As the laser pulse width decreases from milliseconds through microseconds to nanoseconds and picoseconds, the material removal mechanism transitions from melt expulsion to direct ablative removal. This process is similar in many different solid materials, regardless of the material composition. In this paper, a number of ultrafast laser machining examples in a variety of materials are reviewed to illustrate this point. Precise ablation threshold, combined with narrow heat-affected zone, result in high quality materials processing

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Precisely controlled electron-beam lithography and dry etching for micro-patterning of two-dimensional photonic crystal air-hole arrays are described. In the EB lithography of 2DPC patterns which involve periodic air-hole arrays and non-periodic defect waveguides, fine EB dose adjustment is needed especially for the periodic air-hole patterns neighboring non-periodic defect waveguide patterns for suppressing a proximity effect proper to the EB lithography. In the dry etching, precise control of etching parameters such as substrate temperature as well as plasma parameters is needed for achieving air holes with vertical sidewall profiles. Resultant fluctuations of the air holes after etching are as small as 2∼4% in diameter. For the sample fabricated in this way, measured transmittance spectra for the 2DPC waveguide are in good agreement with the calculated ones.

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