Abstract: A semiconductor device includes an input circuit, an output circuit, an insulation circuit, and a semiconductor substrate. The insulation circuit includes at least one capacitor for electrically insulating the input circuit and the output circuit from each other. The at least one capacitor has two electrodes, one of which being electrically connected to the input circuit, and the other of which being electrically connected to the output circuit. The semiconductor device further includes an insulation film that is made of dielectric material and is provided between the at least one capacitor and the semiconductor substrate in a thickness direction of the semiconductor substrate.

Abstract: A semiconductor relay of the invention includes first and second signal terminals, a substrate, a first switch circuit and a control circuit. The substrate includes signal patterns for forming a signal line between the first and second signal terminals. The first switch circuit has a semiconductor switch used to make or break the connection between the first and second signal terminals. The control circuit has a control IC for controlling the first switch circuit. The control IC is mounted on a land of the substrate. The land has a size corresponding to the control IC. A part or all of the land is included in a part of the signal patterns.

Abstract: A semiconductor relay of the invention includes first and second signal terminals, a substrate, a first switch circuit and a control circuit. The substrate includes signal patterns for forming a signal line between the first and second signal terminals. The first switch circuit has a semiconductor switch used to make or break the connection between the first and second signal terminals. The control circuit has a control IC for controlling the first switch circuit. The control IC is mounted on a land of the substrate. The land has a size corresponding to the control IC. A part or all of the land is included in a part of the signal patterns.

Abstract: An optical switch comprises a prism for changing the direction of travel of incident light to be directed toward a further optical fiber; a switching mirror placed to be insertable and removable into and from between a lens block and the prism; and an actuator for driving the mirror, in which incident and emitting optical fibers are placed in the same facing, i.e. on one surface side, of the device body. This structure makes it possible for components to be used in common and integrated, and for the coupling surfaces between the lens block and the optical fibers to be gathered together in one place, thereby enabling cost reduction and size reduction.

Abstract: An optical switch comprises a prism for changing the direction of travel of incident light to be directed toward a further optical fiber; a switching mirror placed to be insertable and removable into and from between a lens block and the prism; and an actuator for driving the mirror, in which incident and emitting optical fibers are placed in the same facing, i.e. on one surface side, of the device body. This structure makes it possible for components to be used in common and integrated, and for the coupling surfaces between the lens block and the optical fibers to be gathered together in one place, thereby enabling cost reduction and size reduction.