Photoirradiation effects on the polymer light-emitting devices (PLEDs) with a semitransparent-Al cathode have been studied. A light-emitting polymers, a poly (p-phenylene vinylene) derivative MDOPPV has been used in this study. Upon photoirradiation, the emission intensity at a constant voltage was rapidly decreased. However, the quantum efficiency of electroluminescence remained constant, indicating the spatial separation between recombination zone and photooxidized defects. On the other hand, the quantum efficiency of photoluminescence rapidly dropped upon similar photoirradation. These can be understood by taking the difference in the spatial distribution and the origin of excitons between electro- and photo-luminescence processes. It was also found that the photooxidation rate of the polymer film whose thickness is ca. 100 nm does not have thickness dependence, suggesting that the photooxidation of the polymer proceeds uniformly throughout the device.

Polyurea thin films containing azo-based nonlinear optical (NLO) chromophore were prepared by co-deposition of 4,4'-diphenylmethane diisocyanate and 2,4-diamino-4'-nitroazobenzene monomers using the ionization-assisted method. The co-deposited film reacted to form polyurea after annealing in the air. The dichroic optical absorption spectra indicated the preferential orientation of dipole moments in the as-deposited film. The substrate bias voltage influenced the optical anisotropy. Maker fringe measurement showed that the films have NLO activity without the poling process.

Digitalization in electronic systems requires the electronics devices in de-coupler sets with low impedance at high frequency, and high reliability. A shield strip type line component with aluminum substrate, its surface oxidized dielectric layer and a conducting polymer electrolyte has been developed. The conducting polymers of polypyrrole and poly(3,4-ethylenedioxythiophene) have been formed by direct chemical oxidative polymerization and electrochemical polymerization on a dielectric layer. Thus, the surface of the dielectric layer is covered with conducting polymer films. The structure of the line component is strip line conformation just like a crushed coaxial cable with in-put and out-put terminals surrounded by the conducting polymer electrolyte. Two types of the components, i.e., a large surface area, 10 20 mm, and a small surface area, 4 4 mm, have been fabricated with polypyrrole and poly(3,4-ethylenedioxythiophene), respectively. The dielectric properties of these line components have been investigated with a Impedance/Gain-phase analyzer and a network analyzer. Due to the high conductivity of the polymer electrolytes, the line components demonstrate low impedance at resonance frequency. Regarding the frequency characteristics of the line components, the impedance and ESR at high frequency are lower than those of the conventional capacitors. Furthermore, the transfer coefficients, S21, are three orders lower than those of other capacitors in a wide frequency band from 10 kHz to 6 GHz. The results indicate the excellent characteristics of the line components for the power line de-coupler set at the boundary of the closed circuit unit.

The mesoporous materials from the self-assembled organic-inorganic compound materials have great possibilities for a variety of applications. However, to make use of these kinds of materials effectively, they must be controlled. In this paper, we are succeeded in powder state pore size control and in significantly fabrication film state for device application use.

The optical recording on an azopolymer surface by the optical fiber probe with a 100 nm diameter aperture was demonstrated. The 150 nm diameter pit was formed by the optical fiber probe coupled with a 50 ns pulse of 10 mW and 488 nm wavelength coherent light.

We have developed a 22 digital optical switch (DOS) composed of four 12 DOS elements and a thermo-optic wavelength tunable filter using silicone resin waveguides. The 22 DOS operated with a switching power of 380 mW, a very low crosstalk of less than -60 dB, and a low insertion loss of less than 2.5 dB at 1.55 µm. We have also developed two types of polymer thermo-optic wavelength tunable filter with a pair of triangular phase shifters. One filter is designed for a large-scale WDM system (32 channels, 0.8 nm spacing) and the other for a small-scale WDM system (10 channels, 0.8 nm spacing). We optimized the arrayed waveguide number, reducing the operating power required by these filters. Moreover, they both operated with a low crosstalk of < -25 dB.

We have developed the new energy storage system utilizing a radical redox reaction of poly (2,2,6,6-tetramethylpiperidinoxy methacrylate), PTMA. The coin-type cell with PTMA cathode demonstrates the charge capacity of is 72 Ah/kg, which corresponds to 65% of the theoretical capacity, and the coulombic efficiency was 90% in first charge-discharge cycle. The results indicate that the stable polyradical cathodes are promising materials due to their high charge utilization and the possibilities for the wide diversity of molecular design.

A new rewritable medium utilizing a guest-host (G-H) polymer-dispersed liquid-crystal (PDLC) film has been developed in our laboratory. The medium is thermally written and electrically erased. It is portable, like paper, and can store recorded data because of the memory effect of smectic-A liquid crystal (SmA LC), which exhibits bistable states of homeotropic and focal conic alignment. Dichroic dye is added to the SmA LC to form the G-H type. An evaluation of the characteristics revealed that this medium exhibits both high contrast and good reliability.

Elemental technologies have been studied to establish the healthcare chip which is an intelligent micro analytical system to detect human health markers from a trail of blood. A two steps process for deep quartz dry-etching was discussed in order to overcome the issues of concave-shaped defects at the bottom of grooves. A coating with 2-methacryloyloxyethylphosphorylcholine (MPC) polymer was studied to suppress the adsorption of bio-substance onto the inner wall of the flow channel on chip and good bio-compatibility was achieved for suppression of protein adsorption and blood cell adhesion. A prototype of healthcare chip was fabricated on polyethylene terephthalate (PET) plate using a micro molding technique. Using this chip, the ion concentrations of pH, Na+, K+, Ca++ were successfully measured with embedded ion sensitive field effect transistors (ISFET's).

Feasibility of a color shutter using ferroelectric liquid crystal polymer panel and a field sequential ultra high-resolution CRT with the color shutter as a color field-switching device was studied. The color shutter consists of ferroelectric liquid crystal polymer panels and color polarizers. First, evaluation indices of the color shutter, such as the color gamut, the average transmittance and the white chromaticity shift, were formulated, and the simulation of evaluation indices was examined, where the spectral transmittance characteristics of the polarizer were changed in steps. It was indicated that there was a tradeoff between the color gamut and the average transmittance of the color shutter, and the shutter configuration that provides 0.096 (63% to NTSC) color gamut and 4.3% average transmittance was selected based on the simulation results. Next, the three-line simultaneous scanning method of the monochrome CRT was improved so that the disturbance due to the raster modulation was eliminated by averaging the distribution of beam luminance apparently. To confirm results of the study, the prototype of 21-inch screen size was produced, and the following display characteristics was obtained: luminance of 71 cd/m2, contrast ratio of 146:1 and color gamut of 0.096 (63% to NTSC) under the standard room lighting environment.

We examined the creep properties and hazard rates of plastic ferrules to ensure the long-term reliablity of optical fiber connections. The endface deformation ΔL had to be smaller than 3 µm to keep the insertion-loss and return-loss fluctuation to acceptable levels in the worst case of random concatenation of similarly deformed plastic ferrules. From the fluctuation data, we estimated the time-to-failure tf at which the ΔL value became 3 µm. We estimated the acceleration parameters, median lifetimes ξ, and hazard rates λ by using tf values based on Weibull statistics. The ξ values decreased rapidly with increasing temperature and relative humidity. We found we could expect small λ values of < 0.1 FIT (FIT=10-9/hour) and of 1 FIT for 20 years in a normal atmosphere (25C/50%RH) and in a more severe case of 25C/90%RH, respectively.

The present paper discusses several promising application areas for optical data links based on high-performance vertical-cavity surface-emitting laser diodes (VCSELs). Both 850 and 980 nm emission wavelength devices realized in the GaAs-AlGaAs or InGaAs-AlGaAs material systems are considered. We show data transmission results of 10 Gb/s signals at 830 nm wavelength over a new high-bandwidth multimode silica fiber of up to 1.6 km length. The same fiber type is employed to demonstrate the first 40 Gb/s transport over 300 m distance by means of a 4-channel coarse wavelength-division multiplexing approach. A first 1 10 linear VCSEL array capable of 10 Gb/s per channel operation is presented for use in next generation parallel optical modules. To improve the singlemode emission characteristics for output power in the 5 mW range we introduce a new device concept incorporating a long monolithic cavity. For low-cost short-distance data links we investigate graded-index polymer optical fibers and report on up to 9 Gb/s transmission over a length of 100 m. Polymer waveguides are also used in an optical layer of a hybrid electrical-optical printed circuit board. Transmitted 10 Gb/s optical data over a prototype board show the potential of this new technology. Finally we present two-dimensional VCSEL arrays for highly parallel data transport on a CMOS chip level. Both 980 and 850 nm bottom emitting devices with modulation capabilities up to 12.5 Gb/s are discussed.

The present paper discusses several promising application areas for optical data links based on high-performance vertical-cavity surface-emitting laser diodes (VCSELs). Both 850 and 980 nm emission wavelength devices realized in the GaAs-AlGaAs or InGaAs-AlGaAs material systems are considered. We show data transmission results of 10 Gb/s signals at 830 nm wavelength over a new high-bandwidth multimode silica fiber of up to 1.6 km length. The same fiber type is employed to demonstrate the first 40 Gb/s transport over 300 m distance by means of a 4-channel coarse wavelength-division multiplexing approach. A first 1 10 linear VCSEL array capable of 10 Gb/s per channel operation is presented for use in next generation parallel optical modules. To improve the singlemode emission characteristics for output power in the 5 mW range we introduce a new device concept incorporating a long monolithic cavity. For low-cost short-distance data links we investigate graded-index polymer optical fibers and report on up to 9 Gb/s transmission over a length of 100 m. Polymer waveguides are also used in an optical layer of a hybrid electrical-optical printed circuit board. Transmitted 10 Gb/s optical data over a prototype board show the potential of this new technology. Finally we present two-dimensional VCSEL arrays for highly parallel data transport on a CMOS chip level. Both 980 and 850 nm bottom emitting devices with modulation capabilities up to 12.5 Gb/s are discussed.

We have proposed parallel optical interconnection technology, or ParaBIT, for high-throughput, low-cost optical interconnections and already developed a prototype parallel optical interconnect module called "ParaBIT-0," which has a total throughput of 28 Gb/s (700 Mb/s 40 channels). We are now developing a compact, high-throughput module called "ParaBIT-1," which has a total throughput of 60 Gb/s (1.25 Gb/s 48 channels) and is designed to achieve the highest-ever throughput density of 3.3 Gb/s/cc. In this paper, we describe the packaging structure, optical coupling structure and transmission characteristics of ParaBIT-1. We also discuss the technical prospect of realizing a parallel optical interconnect module with the bit rate of 2.5 Gb/s/ch.

We propose a compact multi-channel 90 optical deflection device for short-distance optical interconnection. The device consists of stacked bent multimode optical waveguides having reflecting mirrors with bending angles of 90. The structure of the bent multimode optical waveguide with a bending angle of 90 was designed by ray-tracing simulations. The simulated insertion loss for each channel of the device was 0.5 dB. We also propose a simple fabrication process using a pair of multi-channel linear optical waveguides with symmetrical 45 mirrors. An 8-channel 90 optical deflection device was fabricated using polymer materials and basic operation was confirmed. Our device has good potential for use as a high-density optical interconnection device.

Aiming at lower cost and further miniaturization, we developed a new optical coupling system for use as an optical interface of a parallel optical interconnect module, called ParaBIT-1. It consists of a new-structure 24-fiber bare fiber (BF) connector whose main parts are made of molded plastic and a 24-channel optical coupling component using new polymeric optical waveguide film. To prevent bare fibers from breaking, the BF connector plug has a fiber protector. This BF connector can be joined by direct physical contact between bare fibers in fiber guide holes with a 250-µm pitch. The buckling forces of the fibers themselves secure the physical contacts. The average measured insertion loss of the 24-fiber BF connector was 0.05 dB, and the return losses were over 35 dB. The optical coupling components are composed of a 24-ch polymeric optical waveguide film with 45 mirrors and the 24-fiber BF connector interface, and can be assembled by passive alignment. The high thermal stability of the film allows soldering, and the film is fabricated by direct photo patterning. The average insertion losses of the components for transmitter and receiver modules were 1.28 and 1.35 dB, respectively.

Optically patternable light-emitting devices based on conducting polymers were fabricated and were characterized. The cathode of the devices is made with a semitransparent-Al film, which enables to photoinduced degradation of the polymers in air. The optically patternable devices were successfully made with poly (2-methoxy-5-dodecyloxy-p-phenylene vinylene) (MDOPPV), as well as with poly (3-dodecylthiophene) (PAT12). However, optical absorption study indicated that the patterning mechanism of the MDOPPV device is considerably different from that of the PAT12 device.

Polymeric thin films can be prepared by physical vapor deposition in several manners such as direct evaporation of the polymer, co-evaporation of two monomers followed by polyaddition or polycondensation reaction, or evaporation of single monomer followed by chain polymerization. The ionization-assisted deposition (IAD) was proposed as a new method of polymer deposition that has special features such as activation of polymerization reaction and aligning of the dipole orientation. These mechanisms were utilized for the formation of vinyl polymer and polyurea thin films aiming for such applications as organic light emitting diodes and piezoelectric devices.

We have developed a polymer tunable wavelength filter using cross-linked silicone as a waveguide material for wavelength division multiplexing (WDM) systems. The filter operated with a low insertion loss of 3.6-4.1 dB, a low crosstalk of < -30 dB, and a wide tuning range of 10 nm in the 20 to 80C temperature region without any changes in the spectral profile. We investigated the optical characteristics of the 32-ch WDM signals transmitted through the filter. We realized a stable filtering operation by introducing a feedback system. We also applied the filter to a WDM/SCM (subcarrier multiplexing) broadcast-and-select LAN system. We were able to realize a LAN system which operated at 6 Mbit/s and had 3200 channels by using 10-wavelength WDM signal. This suggests that our polymer tunable wavelength filter is suitable for practical use.

Topographical changes induced by optical near-field around photo-irradiated nanoparticles were attained using a pulsed laser with a large peak power as a light source. The arrayed structure of nanoparticles was transcribed on urethane-urea azo copolymer film as dent structure. The experiments by the pulsed laser of different wavelength showed that the topographical change was caused by the light absorption. The dent diameter and the dent depth changed depending on the diameter of nanoparticles.