Abstract: An ultrasonic probe provided with an ultrasonic wave-transmitting/receiving element comprising a 1-3 type or 2-2 type composite piezoelectric body exposing a piezoelectric monocrystal from at least one of the faces of the composite piezoelectric body, and an electrode mounted on at least one of the faces of the composite piezoelectric body, wherein the composite piezoelectric body comprises a piezoelectric monocrystal whose electromechanical coupling coefficient ratio k.sub.33 /k.sub.t is 1.6 or more, and a resin whose acoustic impedance Zp is 4.times.10.sup.6 kg/m.sup.2 s or less.

Abstract: Disclosed is a piezoelectric single crystal which has a large electromechanical coupling coefficient and hardly brings about depolarization due to the effect of heat in, e.g., the steps of manufacturing an ultrasonic transmitting/receiving element. The piezoelectric single crystal consists essentially of a general formula:Pb{[M1.sub.1/3 Nb.sub.(2/3)-(2z/3) Ta.sub.2z/3 ].sub.1-x-y Ti.sub.x M2.sub.y }O.sup. 3wherein M1 represents at least one metal selected from the group consisting of Zn, Ni, and Mg, M2 represents at least one metal selected from the group consisting of Pt, Fe, Bi, Rh, and Ir, and x, y, and z are defined as 0.05.ltoreq.x.ltoreq.0.2, 0.00001.ltoreq.y.ltoreq.0.01, and 0.ltoreq.z.ltoreq.0.1, respectively.

Abstract: An optical wavelength-converting device for generating the second-harmonic wave through Cerenkov radiation has a substrate made from nonlinear optical crystal which acts as a cladding layer. Formed on the top surface of the substrate is a long, narrow optical waveguide layer, whose refractive index is larger than that of the substrate. In the substrate, multi-layered domain-inverted sections are formed. With this arrangement, the nonlinear coefficient is locally changed, thereby compensating for phase mismatching between the fundamental wave and the second-harmonic wave in the direction perpendicular to the substrate's surface. This compensation helps improve the efficiency in converting the laser input light of the fundamental wave into the second-harmonic wave.

Abstract: A method of heat treatment for purifying a Groups II-VI compound semiconductor and for producing a purity Groups II-VI compound semiconductor crystal using a sealed container placed a Groups II-VI compound semiconductor crystal as a raw material is disclosed. The process includes heating means applied to the sealed container having a temperature difference which has a high-temperature zone and a low-temperature zone into the sealed container, placing the raw material into the high-temperature zone of the sealed container, using a heat atom making an atmosphere of either a Group II element or a Group VI element, or a mixed atmosphere of either which is necessary to treat the Groups II-VI compound semiconductor into the sealed container, and using a Groups II-VI compound semiconductor as raw material.

Abstract: An apparatus for liquid-phase epitaxial growth is characterized in that the greater part of that surface of a well, made of carbon, which contacts with a solution for liquid-phase epitaxial growth is covered with a fused quartz layer.

Abstract: A red light emitting gallium phosphide device comprises an n-type substrate, an n-type layer formed on the substrate using a liquid phase epitaxial growth method, and a p-type layer formed on the n-type layer using the liquid phase epitaxial growth method, the donor concentration of the n-type layer ranging from 1.8 .times. 10.sup.17 cm.sup..sup.-3 to 5.8 .times. 10.sup.17 cm.sup..sup.-3.

Abstract: A method of manufacturing a gallium phosphide (GaP) red-emitting device by forming at least one n-type GaP layer on an n-type GaP substrate by the liquid phase epitaxial growth process and further depositing a p-type GaP layer on said n-type GaP layer, thereby providing a p-n junction contributing to emission of light, characterized in that the method comprises reducing the surface donor concentration of the n-type GaP layer to below 1 .times. 10.sup.18 cm.sup.-.sup.3 ; and epitaxially growing at least the light emitting region of the p-type GaP layer by cooling a solution for epitaxial growth of said p-type GaP layer at a slower rate than 5.degree.C per minute.