Abstract: First and second switches are connected in series between first and second terminals. A third switch is provided between a first node between the first terminal and the first switch, and a first resistive-element. A fourth switch is provided between a second node between the first and second switches, and the reference power-source. A controller switches the first to fourth switches between conduction and non-conduction states. First, third, fifth, and seventh delay-circuits are provided between the first to fourth switches and the controller and delay first, second, third, fourth control signals for switching the first to fourth switches from a conduction state to a non-conduction state, respectively. Second, fourth, sixth, and eighth delay-circuits are provided between the first to fourth switches and the controller and delay the first, second, third, fourth control signals for switching the first to fourth switches to a non-conduction state to a conduction state, respectively.

Abstract: First and second switches are connected in series between first and second terminals. A third switch is provided between a first node between the first terminal and the first switch, and a first resistive-element. A fourth switch is provided between a second node between the first and second switches, and the reference power-source. A controller switches the first to fourth switches between conduction and non-conduction states. First, third, fifth, and seventh delay-circuits are provided between the first to fourth switches and the controller and delay first, second, third, fourth control signals for switching the first to fourth switches from a conduction state to a non-conduction state, respectively. Second, fourth, sixth, and eighth delay-circuits are provided between the first to fourth switches and the controller and delay the first, second, third, fourth control signals for switching the first to fourth switches to a non-conduction state to a conduction state, respectively.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: In an optical modulator 115 of an embodiment, an optical waveguide core 121 is configured from an n? type semiconductor region 134, a gate insulating film 136 on the n? type semiconductor region 134, and a p? type semiconductor region 137 on the gate insulating film 136. Further, a width W1 of the n? type semiconductor region 134 and a width W1 of the p? type semiconductor region 137 are equally formed and are layered without being shifted. Therefore, an optical modulator having stable optical characteristics can be provided.

Abstract: In an optical modulator 115 of an embodiment, an optical waveguide core 121 is configured from an n? type semiconductor region 134, a gate insulating film 136 on the n? type semiconductor region 134, and a p? type semiconductor region 137 on the gate insulating film 136. Further, a width W1 of the n? type semiconductor region 134 and a width W1 of the p? type semiconductor region 137 are equally formed and are layered without being shifted. Therefore, an optical modulator having stable optical characteristics can be provided.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: There is provided a photoelectric conversion module that can be mounted two-dimensionally over a device board in a high-density, low-height manner and cooled efficiently with an easy-to-install collective-type radiator. In the photoelectric conversion module mounted over the device board, an optical connector is attached to that surface of an optical subassembly facing the device board. An electric connector has at least two sides thereof opened so that the optical transmission medium is threaded therethrough and extended through at least two facing sides of the optical subassembly. The optical transmission medium is thus extended between the optical subassembly and the device board in a vertically stacked manner.

Abstract: In an optical semiconductor device related to the present invention, a first light source outputting light having a first polarization, a second light source outputting light having a second polarization, a first optical modulator being optically connected to an output side of the first light source and modulating the light that is output from the first light source to output a light signal, a second optical modulator being optically connected to an output side of the second light source and modulating the light that is output from the second light source to output a light signal, and an optical multiplexer coupling the light signal that is output from the first optical modulator with the light signal that is output from the second optical modulator to output a coupled light signal, are integrated on a semiconductor substrate together.

Abstract: An optical device includes a ridge-like optical waveguide portion, a mesa protector portion that is arranged in parallel to the optical waveguide portion, a resin portion that covers upper parts of the mesa protector portion and is disposed at both sides of the mesa protector portion, an electrode that is disposed on the optical waveguide portion, an electrode pad that is disposed on the resin portion located at an opposite side to the optical waveguide portion with respect to the mesa protector portion, and a connection portion that is disposed on the resin portion and electrically connects the electrode to the electrode pad.

Abstract: There is provided a photoelectric conversion module that can be mounted two-dimensionally over a device board in a high-density, low-height manner and cooled efficiently with an easy-to-install collective-type radiator. In the photoelectric conversion module mounted over the device board, an optical connector is attached to that surface of an optical subassembly facing the device board. An electric connector has at least two sides thereof opened so that the optical transmission medium is threaded therethrough and extended through at least two facing sides of the optical subassembly. The optical transmission medium is thus extended between the optical subassembly and the device board in a vertically stacked manner.

Abstract: A core of an optical waveguide and a core of a waveguide type optical device are adjacently disposed, and a layer is continuously formed at one end of the core of the waveguide type optical device, wherein an effective refractive index of the layer decreases toward a long axis direction of the optical waveguide stripe.

Abstract: An optical device includes a substrate and a first optical waveguide including a mesa. The mesa includes a first lower clad layer portion, a first core layer portion, and a first upper clad layer portion. The first lower clad layer portion, the first core layer portion, and the first upper clad layer portion are disposed in this order from the substrate side. The optical device also includes a first etch stop layer configured to stop etching when the first optical waveguide is formed. The first etch stop layer being laminated over the substrate. The first optical waveguide is laminated on the first etch stop layer.

Abstract: An optical device includes a first substrate, having first and second surfaces, and a second substrate having a third surface. The first substrate includes: a laser unit, having an active layer and emitting light into the first substrate from the active layer; a reflecting mirror, having a plane obliquely intersecting an optical axis of light emitted from the laser unit, and being formed on the first surface so as to reflect the light toward the second surface; and a convex lens, being formed in a region on the second surface, the region including an optical axis of the light reflected by the reflecting mirror. The second substrate is provided with a grating coupler and an optical waveguide on the third surface, the optical waveguide having light incident on the grating coupler propagating therethrough.

Abstract: Beams of light having wavelengths different from each other are generated in a plurality of light generation portions, the beams of light each generated in the plurality of light generation portions are reflected by a monolithic integrated mirror and are incident to a condenser lens, and emission positions on the condenser lens of the beams of light each generated in the plurality of light generation portions deviate from a central position of the condenser lens by a predetermined amount.

Abstract: A wavelength tunable filter and a wavelength tunable laser module are a codirectional coupler type whose characteristics do not vary significantly with a process error. They are structured so as to include a semiconductor substrate which has a first optical waveguide and a second optical waveguide. The first and the second optical waveguides are extended from a first side of the semiconductor substrate to an opposing second side thereof. The first optical waveguide includes a first core layer, which has a planar layout having periodic convexes and concaves, and a pair of electrodes, which vertically sandwich the first core layer. The second optical waveguide includes a second core layer, which has a lower refractive index than the first core layer. Further, a layer having the same composition and film thickness as the second core layer is placed under the first core layer.

Abstract: An optical device includes a substrate and a first optical waveguide including a mesa. The mesa includes a first lower clad layer portion, a first core layer portion, and a first upper clad layer portion. The first lower clad layer portion, the first core layer portion, and the first upper clad layer portion are disposed in this order from the substrate side. The optical device also includes a first etch stop layer configured to stop etching when the first optical waveguide is formed. The first etch stop layer being laminated over the substrate. The first optical waveguide is laminated on the first etch stop layer.

Abstract: An optical device includes a ridge-like optical waveguide portion, a mesa protector portion that is arranged in parallel to the optical waveguide portion, a resin portion that covers upper parts of the mesa protector portion and is disposed at both sides of the mesa protector portion, an electrode that is disposed on the optical waveguide portion, an electrode pad that is disposed on the resin portion located at an opposite side to the optical waveguide portion with respect to the mesa protector portion, and a connection portion that is disposed on the resin portion and electrically connects the electrode to the electrode pad.