Abstract: In an attachment structure for an annular metal seal, an annular metal seal includes a seal body configured such that at least one of outer corner portions thereof corresponding to an inner corner portion of the seal groove has a sharp ridge, and in a state where a positioning ring is held between an inner-side side surface of the seal groove and an inner-diameter-side side surface or an outer-diameter-side side surface of the seal body, the annular metal seal is fitted in the seal groove with the positioning ring abutted on at least a portion of the inner-side side surface of the seal groove and the sharp ridge of the seal body spaced from the inner corner portion of the seal groove, and the first member and the second member are fastened with each other, so that inner and an outer sides of the annular metal seal are sealed.

Abstract: The metal seal has a middle base portion 3 of which cross-sectional configuration is laterally long rectangular, a first main convex portion 1 and a first auxiliary convex portion 11, and a second main convex portion 2 and a second auxiliary convex portion 12 respectively disposed on both ends of long sides 3A of the middle base portion 3. Ridge lines of the convex portions 1, 11, 2, and 12 form common straight lines L10 and L20 continuous to short sides of the rectangular.

Abstract: The metal seal has a middle base portion 3 of which cross-sectional configuration is laterally long rectangular, a first main convex portion 1 and a first auxiliary convex portion 11, and a second main convex portion 2 and a second auxiliary convex portion 12 respectively disposed on both ends of long sides 3A of the middle base portion 3. Ridge lines of the convex portions 1, 11, 2, and 12 form common straight lines L10 and L20 continuous to short sides of the rectangular.

Abstract: Disclosed is an antenna capable of receiving a very wide band of frequencies. The antenna includes a pair of antenna elements and a pair of feeding legs, which are arranged symmetrically with respect to a line L, with a narrow space G in between.

Abstract: Disclosed is an antenna capable of receiving a very wide band of frequencies. The antenna includes a pair of antenna elements and a pair of feeding legs, which are arranged symmetrically with respect to a line L, with a narrow space G in between.

Abstract: An electromagnetic screen (1) comprises a plurality of antennas (4) each of which reflects an electromagnetic wave having a specific frequency. The plurality of antennas (4) are arranged so as to constitute a pattern. Each of the antennas (4) has three segment-shaped first element parts (4a) and three segment-shaped second element parts (4b). The three first element parts (4a) radially extend from the center of the antenna (4) by substantially the same length such that any two of the three first element parts (4a) form an angle of 120° with each other. Each of the second element parts (4b) are connected to an outer edge of a corresponding one of the first element parts (4a).

Abstract: On one side of a passageway for an identification subject 10 with an IC tag 7 to pass, an antenna is provided for reading information stored in the IC tag 7, and a front wave-absorbing wall 2 and a rear wave-absorbing wall 3 are provided protruding from the vicinity of the front and rear edges of the antenna 8 toward the passageway 13 such that the walls narrow the half-power angle ? of the radio wave radiated from the antenna 8 over a horizontal plane. A wave-absorbing side wall 1 is also provided on the other side of the passageway 13. With such a structure, the propagation area of the radio wave can be controlled so that the reading area of the IC tag 7 can be limited, and the influence of the reflected wave is suppressed.

Abstract: A radio wave shield selectively shields radio waves of a specific frequency band.

Abstract: An electromagnetic screen (1) comprises a plurality of antennas (4) each of which reflects an electromagnetic wave having a specific frequency. The plurality of antennas (4) are arranged so as to constitute a pattern. Each of the antennas (4) has three segment-shaped first element parts (4a) and three segment-shaped second element parts (4b). The three first element parts (4a) radially extend from the center of the antenna (4) by substantially the same length such that any two of the three first element parts (4a) form an angle of 120° with each other. Each of the second element parts (4b) are connected to an outer edge of a corresponding one of the first element parts (4a).

Abstract: A radio wave shield selectively shields radio waves of a specific frequency band.