Abstract: A Gaussian-beam antenna invention comprises a transmitting circuit or a receiving circuit, a resonator consisting of a pair of reflecting mirrors, which consist of a spherical mirror and a planar mirror or two spherical mirrors, and a transmission line which transmits a high-frequency signal between the aforesaid transmitting circuit or receiving circuit and the resonator, one reflecting mirror of the resonator having an electromagnetic wave coupling region constituted as a circular partially transparent mirror surface region having its center on the optical axis.

Abstract: A Gaussian-beam oscillator for microwave and millimeter wave comprising a negative resistance amplifier circuit which produces and amplifies a high-frequency signal, a resonator consisting of a pair of reflecting mirrors, which consist of a spherical mirror and a planar mirror or two spherical mirrors, and a wave path which transmits the high-frequency signal between said resonator and said negative resistance amplifier circuit, one reflecting mirror of said resonator having an electromagnetic wave coupling region constituted as a circular partially transparent mirror surface region having its center on the optical axis, the other reflecting mirror having a strip element provided at the center of the optical axis and on the rear surface of said strip element having a coupling region for coupling with said wave path, said one reflecting mirror constituting said resonator and having the electromagnetic wave coupling region having a higher reflectance than the reflectance of the other reflecting mirror.

Abstract: The surface characteristics with respect to a high-frequency electromagnetic field of a material to be tested are measured by placing opposite a flat mirror material to be tested one of a pair of concave spherical reflection mirrors fabricated in the same way and formed with high-reflectance circular coupling regions, placing the other spherical reflection mirror at a position symmetrical to the one reflection mirror with respect to the flat mirror material as the plane of symmetry, measuring the Q value of the open resonator formed by the one reflection mirror and the flat mirror material, removing the flat mirror material from the optical axis, measuring the Q value of the open resonator formed by the pair of spherical reflection mirrors, calculating the absolute value of the reflectance of the flat mirror material to be tested from the difference between the two measured Q values, and calculating the phase of the reflected wave at the surface of the flat mirror material to be tested from the measured reson

Abstract: A superconducting weak link device includes a plurality of interconnected small superconducting regions and a plurality of conductive bridges which connect adjacent the small superconducting regions in which the length of the bridges is in the range from 1 to 5.31 times the coherence length.

Abstract: An open resonator comprises two concave spherical reflectors or one spherical and one plane reflectors positioned so as to form a resonant structure and each being provided at an electromagnetic coupling region thereof with a large number of conductor stripes disposed in parallel at a spacing sufficiently small in comparison with the wavelength of an incident electromagnetic wave. The diameter of the circular coupling region can be made very large in comparison with the wavelength. An ultra-high Q value can be obtained with the open resonator with very high excitation efficiency to a resonator mode. The Q value of the open resonator can be varied with the angle between the directions of the conductor stripes of the two reflecting mirrors.