An electrochromic display based on a Prussian-blue-modified electrode is described. Prussian blues are deposited electrochemically in a solution of ferric-ferricyanide. Current flow at +0.2 and +1.0 V is due to the reduction of Fe3+ and the oxidation of Fe2+ in the Prussian-blue coating, respectively. The result is a display that switches from clear to blue, has high stability, and has a response of less than 100 ms.

Velocities and attenuations of piezoelectric leaky surface waves in LiNbO3 are analyzed. As a result, we have found that the effective electromechanical coupling coefficient of the leaky surface wave propagating along the X axis of a 64° rotated Y-cut plane is very large, K2 = 0.113, and the attenuation of this wave, caused by radiation of the energy into the solid, is 0.036 dB/wavelength for a free surface and goes to zero for a metalized surface. Moreover, K2 of the elastic surface wave for a 130° rotated Y-cut, X propagation, is found to be larger than that for a Y cut, Z propagation. The theory is verified experimentally. The theoretical analysis and experiments on amplification are performed for these types of waves. In an experiment utilizing the leaky surface wave, net terminal gain of 13 dB/cm is observed for the interaction between the carrier in 200-Ω cm Si wafer (0.3×3×10 mm), separately mounted on a LiNbO3 surface, and the leaky surface wave. The air gap between the Si wafer and LiNbO3 single crystal is about 0.5 mμ.

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This paper presents a new and simplified equivalent circuit model for an IDT. The model developed here provides more accuracy than the well-known crossed field Smith-model, since it contains the energy storage effect in addition to usual secondary effects. By applying the image parameter theory to the new model, the admittance matrix Y ij of the equivalent three-port model for an N-pair IDT has been derived in concise closed form. As an application, the relations of the radiation conductances to metallization ratios for an IDT are investigated.

The third-order elastic constants of lithium niobate have been measured by small-amplitude ultrasonic waves as a function of applied stress, including the piezoelectric effects.

Large flawless crystals of ZnO up to 25×10×5 mm3 in size have been grown hydrothermally in a specially designed autoclave. Difficulties on the hydrothermal growth of ZnO single crystals were almost surmouted by in situ determination of solution temperatures under operating conditions. The characteristics of the growth crystals are discussed on the basis of the correlation with growth conditions, and it is found that a nonstoichiometry in the grown ZnO is enhanced with being apt to involve O vacancies due to a reductive atomosphere under hydrothermal conditions and also is related to their some properties.

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TEm-TMn mode conversion by electro-optic and acousto-optic effects in a metal-diffused optical waveguide is described theoretically. Elastic surface waves and laser beams propagate along the X axis on Y-cut LiNbO3 single crystals, i.e., interactions are collinear. We predict completely the TE1-TM1 mode conversion at an elastic surface wave power of 33 mW along an interaction length of 5 mm with a width of 1 mm.