Abstract: Includes a stem with a hole, a dielectric sealed into the hole of the stem and including a pair of pin insertion holes, and a pair of high frequency signal pins that penetrate and fit into the pair of pin insertion holes of the dielectric, and constituting differential lines connected to an optical semiconductor element.

Abstract: An optical module includes an optical connector on one end of a package for storing a carrier including an optical element, and a laminated ceramic feedthrough disposed on the other end of the package. The feedthrough includes on an outer surface an electrical terminal perpendicular to the optical axis of light incident on and exiting from the optical connector, and includes on its inner surface a chip carrier connection terminal connected to the electrical terminal. A flexible printed circuit board includes a connection pad acting as an electrical terminal at a position corresponding to the electrical terminal of the feedthrough and is fixed to the feedthrough with an anisotropic conductive adhesive.

Abstract: Includes a stem with a hole, a dielectric sealed into the hole of the stem and including a pair of pin insertion holes, and a pair of high frequency signal pins that penetrate and fit into the pair of pin insertion holes of the dielectric, and constituting differential lines connected to an optical semiconductor element.

Abstract: Includes a stem with a hole, a dielectric sealed into the hole of the stem and including a pair of pin insertion holes, and a pair of high frequency signal pins that penetrate and fit into the pair of pin insertion holes of the dielectric, and constituting differential lines connected to an optical semiconductor element.

Abstract: An optical module includes a stem; a first lead pin and a second lead pin for receiving differential signals, the first and second lead pins penetrating the stem; a mount block fixed to the stem; a laser diode having a pair of electrodes; a submount mounted on the mount block and having a matching resistance, an interdigital capacitor, and a plurality of electrode patterns on a surface on the submount; and a first wire and a second wire electrically connecting the submount to the first and second lead pins, respectively. The laser diode is mounted on one of the electrode patterns on the submount and connected to another one of the electrode patterns on the submount by a third wire such that the laser diode, together with the matching resistance and the interdigital capacitor, forms an electrical circuit. The value of the matching resistance is smaller than an impedance value of a differential signal source supplying the differential signals minus the resistance of the laser diode.

Abstract: A heat radiation blocking fluororesin film comprising a fluororesin containing a hexaboride.

Abstract: There is provided a light receiving element carrier including first through fourth layers laminated, a differential pair of vertical vias, one of them penetrating the second layer, and the other one of them penetrating the third layer, a broadside-coupled differential pair, one of them being located on a first boundary plane between the first and second layers, for connecting a high-frequency terminal to the one of the differential pair of vertical vias, and the other one of them being located on a third boundary plane between the third and fourth layers, for connecting another high-frequency terminal to the other one of the differential pair of vertical vias, and a differential pair of output lines located on a second boundary plane between the second and third layers, they extending on a terrace portion formed of a surface of the third layer which is partially exposed like a terrace.

Abstract: A fluorocopolymer film formed by molding at a molding temperature of at most 320° C. a fluorocopolymer comprising repeating units based on ethylene, repeating units based on tetrafluoroethylene, repeating units based on hexafluoropropylene and repeating units based on a fluoroalkyl vinyl ether represented by CF2?CFORf (wherein Rf represents a C1-10 fluoroalkyl group), having a molar ratio of the repeating units based on ethylene/the repeating units based on tetrafluoroethylene of from 10/90 to 60/40, a content of the repeating units based on hexafluoropropylene to the total repeating units of from 0.1 to 20 mol % and a content of the fluoroalkyl vinyl ether to the total repeating units of from 0.1 to 10 mol %, and having a volumetric flow rate of from 0.1 to 30 mm3/sec at 297° C.

Abstract: Includes a stem with a hole, a dielectric sealed into the hole of the stem and including a pair of pin insertion holes, and a pair of high frequency signal pins that penetrate and fit into the pair of pin insertion holes of the dielectric, and constituting differential lines connected to an optical semiconductor element.

Abstract: The present invention includes a first conductor line connected to one end of an optical semiconductor element (20), and supplying an electric signal to this optical semiconductor element (20); a second conductor line connected to the other end of the optical semiconductor element (20), and supplying an electric signal to this optical semiconductor element (20); a first inductance element (21a) connected to the one end of the optical semiconductor element (20), and cutting off the electric signal at a high frequency; and a second inductance element (21b) connected to the other end of the optical semiconductor element (20), and cutting off the electric signal at the high frequency, wherein the first and the second conductor lines constitute differential lines.

Abstract: There is provided a light receiving element carrier including first through fourth layers laminated, a differential pair of vertical vias, one of them penetrating the second layer, and the other one of them penetrating the third layer, a broadside-coupled differential pair, one of them being located on a first boundary plane between the first and second layers, for connecting a high-frequency terminal to the one of the differential pair of vertical vias, and the other one of them being located on a third boundary plane between the third and fourth layers, for connecting another high-frequency terminal to the other one of the differential pair of vertical vias, and a differential pair of output lines located on a second boundary plane between the second and third layers, they extending on a terrace portion formed of a surface of the third layer which is partially exposed like a terrace.

Abstract: In a conventional optical element module, a filter substrate mounting an air-core coil thereto is mounted in the vicinity of a light emitting element, and the light emitting element and the air-core coil are electrically connected to each other by a bonding wire, etc. Therefore, a problem exists in that it is difficult to set the length of a line path between the light emitting element and the air-core coil to about 1 mm or less, and no preferable high frequency characteristics are obtained.

Abstract: A vertical transition device for differential stripline paths, connects differential microstrip paths on a horizontal plane with differential triplate paths on another horizontal plane in a multilayered architecture. The differential microstrip paths include a pair of differential microstrip lines. The differential triplate paths include a pair of triplate lines. The differential microstrip lines are connected with the differential triplate lines by via-holes within the transition device, respectively.

Abstract: A tetrafluoroethylene-ethylene copolymer (ETFE) film, wherein polar groups are present on the surface of the film after a surface treatment, and the surface roughness Ra is at most the surface roughness Ra of the surface of an untreated film; an ETFE film, wherein polar groups are present on the surface of the film after a surface treatment, and the amount of a weak boundary layer is at most one time of the amount of a weak boundary layer on the surface of an untreated film; a laminate employing such a film having an extremely excellent bonding strength; and a process for producing it with a mass production property.