Abstract: An antenna module is an antenna module including at least a first radiation electrode, and a first power feeding electrode coupled with the first radiation electrode, and includes: a first dielectric layer including the first power feeding electrode; and a second dielectric layer disposed at one side of the first dielectric layer in a thickness direction of the first power feeding electrode, and a fracture toughness value of the second dielectric layer is larger than a fracture toughness value of the first dielectric layer.

Abstract: An ionization vacuum gauge which can stably perform measurements of pressure in the intermediate vacuum to high vacuum regions, that is performed by an ionization-type first measurement element, as well as in the measurement region intrinsic to a second measurement element. This ionization vacuum gauge comprises a measurement element vessel, and first and second measurement parts provided within this measurement element vessel. The first measurement part comprises component electrodes including a filament, grid and ion collector, and is of an ionization-type construction for measurement of the pressure of vacuum states. The second measurement part is of a construction having different functions from those of the first measurement part, and is disposed in a space that is near the extension of the grid axis, and is away from the principal space for flying of thermal electrons emitted from the filament.

Abstract: It is an object of the present invention to provide an ionization vacuum gauge which can stably perform measurements of pressure in the intermediate vacuum to high vacuum regions, that is performed by an ionization-type first measurement element, as well as in the measurement region intrinsic to a second measurement element. This ionization vacuum gauge comprises a measurement element vessel, and first and second measurement parts provided within this measurement element vessel. The first measurement part comprises component electrodes including a filament, grid and ion collector, and is of an ionization-type construction for measurement of the pressure of vacuum states. The second measurement part is of a construction having different functions from those of the first measurement part, and is disposed in a space that is near the extension of the grid axis, and is away from the principal space for flying of thermal electrons emitted from the filament.