Recent development in the researches on the electrical properties of solid polymers is discussed. Emphasis is laid on the electrical conduction and the dielectric properties. Ionic conduction is discussed in terms of ionic carrier sources and ionic mobility. Electronic conduction is discussed mainly from a physico-chemical point of view; photo-carrier generation by molecular excitation and electronic transport by molecular allignment. The limiting dielectric constant at high frequencies and refractive index are discussed as a function of molecular structure. The dielectric relaxation processes are explained by various modes of molecular motion. Applications of polymers to the electrical and electronic engineering are pointed out in each section
The authors have made experimental and analytical studies on the reflection-characteristics of retro-reflective labels (Scotch light). The characteristic curves of the angle θ made between the retro-reflective labels and the light when it reflects on the label were measured. Both the light projector and the receiver were kept in the same position (observing angle β=0°). As source of light He-Ne gas laser and W-lamp was used. Next, the authors analysed the reflective characteristics with regard to the depth and the space between one sphere and another (measured by a microscopic-photograph). From these studies, the authors have come to the conclusion that the flatness of the shoulder of the reflecive characteristics is related to the depth of deposited spheres, and that the skirt of the curve is related to the spacing of the spheres. If the observing angle β is suitably changed, projected shoulder characteristics are observed. Finally the figure of merit of the retro-reflective labels are discussed.
Three systems of rare gas mixtures Ar-Kr, Kr-Xe and Ar-Xe are used to construct a single laser with two simultaneously lasing atomic species. The variation of cw output power at each wavelength is determined experimentally in detail as a function of discharge current, composition of gases or total filling pressure. In each of the gas mixtures examined the laser radiation from a constituent species with the higher ionization energy comes to have a very large exponent in the current dependent factor In as the content of the other species with the lower ionization energy is increased. Simultaneous lasing in the three primary colors is obtained with Ar-Kr and Ar-Xe mixtures. The experimental data obtained can be explained qualitatively by considering the change of E/p with the composition of gases. Observed characteristics of laser radiations for the three different systems were discussed from a practical point of view.
Modulation characteristics and stability of current modulated He-Ne lasers in case of excess excitation are investigated. Impedances of laser tubes under small signals are measured when the bore diameter, gas pressure and the capillary length are varied, and its equivalent circuit is obtained. Dynamical characteristics of current and laser oscillation under large signals are measured. In case of on-off modulation, the laser oscillation builds up rapidly after a 2 AS delay against the discharge current and decays with a time constant of about 3, as at the maximum. Under typical operating conditions, on-off modulation up to 200 kHz is the practical upper limit. Rate-equation approach gives a qualitative description of the build-up of laser oscillation. Drift and stability of characteristics of laser oscillation vs. current are discussed. Applica-tions to picture recording are also briefly noted.
Films by thermal decomposition of organic tin compounds, were deposited on ceramic substrates. Using these films, the authors produced film resistors. In order to investigate the characteristics of these films, physical and electrical measurements were performed. From the investigation of X-ray diffraction patterns and electron micrographs, it was found that films produced at a comparatively low temperature consist of tin oxide and amor-phous carbon and films produced at a higher temperature consist of tin and carbon like graphite. Depending on the characteristics of the tin and carbon complex film resistor, it is possible to increase sheet resistivity without impairing, the electrical properties of the carbon film resistor. Moreover the various electrical properties of the complex films, in which the sheet resistivity is under a few kΩ/sq., are more satisfactory as compared with the carbon film resistor.