Provided is an optical module comprising a plate-like metal stem and a semiconductor optical modulation element mounted to a dielectric substrate provided on one side of the metal stem, wherein the metal stem has a metal stem penetration section in which a metal lead pin is inserted coaxially in a penetration hole which is formed in the metal stem and a dielectric member is provided to fill the penetration hole around the outer circumference of the lead pin, and a signal for modulation is supplied to the semiconductor optical modulation element connected in parallel with a terminal matching circuit, from the other side of the metal stem via the metal stem penetration section, wherein the terminal matching circuit is configured by a series connecting body which is comprised of a first resistor and a parallel body which is comprised of a second resistor and a capacitor.

An emitter array may comprise a plurality of emitters and a metallization layer to electrically connect the plurality of emitters. The metallization layer may have a first end and a second end. The plurality of emitters may include a first emitter and a second emitter. The first emitter may be located closer to the first end than the second emitter. The first emitter and the second emitter have differently sized structures to compensate for a first impedance of the metallization layer between the first end and the first emitter and a second impedance between the first end and the second emitter.

An optical chip may include a vertical-cavity surface-emitting laser (VCSEL) structure. The optical chip may include a capacitor over at least a portion of an active layer of the VCSEL structure that is outside of an active region of the VCSEL structure. The capacitor may include a first metal layer over the portion of the active layer, a dielectric layer on the first metal layer, and a second metal layer on the dielectric layer. The optical chip may include an isolation region between a substrate of the VCSEL and a portion of the capacitor outside of the VCSEL.

A method for manufacturing a monolithically integrated semiconductor optical integrated element comprising a DFB laser, an EA modulator, and a SOA disposed in a light emitting direction, comprising the step of forming a semiconductor wafer on which the elements are two-dimensionally arrayed and aligned the optical axes; cleaving the semiconductor wafer along a plane orthogonal to the light emitting direction to form a semiconductor bar including a plurality of the elements arranged one-dimensionally along a direction orthogonal to the light emitting direction such that the elements adjacent to each other share an identical cleavage end face as a light emission surface; inspecting the semiconductor bar by driving the SOA and the DFB laser through a connection wiring part together; and separating out the semiconductor bar after the inspection to cut the connection wiring part connecting the electrode of the SOA and the DFB laser to isolate from each other.

A structure for impedance signal lines of a transistor outline (TO)-can type semiconductor package is disclosed. The TO-can type semiconductor package may include a header including a semiconductor laser diode disposed on one side thereof; a signal line penetrating the header and including a one end protruding from the one side of the header; and an edge-coupled microstrip (ECM) portion connected to the signal line. The ECM portion is configured to include a dielectric and ECM lines are formed as conductive patterns having predetermined widths and leaving a predetermined space therebetween on a first side of the dielectric, and respectively connected to the signal lines.

A driver circuit may include a first inductor with a first terminal coupled to a first voltage terminal and a first switch with a first and a second terminal. The first terminal of the first switch is coupled to a second terminal of the first inductor via a first node and the second terminal of the first switch is coupled to a second voltage terminal. Moreover, the driver circuit may include a diode with a first terminal coupled to the first node, an output terminal, and a first capacitor with a first electrode coupled to a second terminal of the diode and a second electrode coupled to the output terminal.

A semiconductor light emitting device includes a microstrip substrate with a single-ended transmission line on a top surface, wherein the single-ended transmission line extends from a first end portion to a second end portion, the microstrip substrate has a ground plane on a bottom surface, and the ground plane is opposed and bonded to the conductive pattern. The single-ended transmission line includes a first section and a second section, wherein the second section extends from the first section and includes the second end portion. The second section is lower in characteristic impedance than the first section. A load circuit that includes the wire, the optical modulator, and the termination resistor is electrically connected between the second end portion and the conductive pattern. The load circuit is equal to or lower in the characteristic impedance than the second section.

A laser diode driver circuit includes a first pair of contacts and connectors coupled to an anode of the laser diode. An inductance of each of the first pair of contacts and connectors is the same. A second pair of contacts and connectors are coupled to a cathode of the laser diode. An inductance of each of the second pair of contacts and connectors is the same. The laser diode driver circuit also includes current driving circuitry.

A semiconductor optical device includes: a laser for emitting light; a modulator for modulating the light using an electroabsorption effect; a chip capacitor that is electrically connected in parallel to the laser; a chip inductor that is electrically connected in series to the chip capacitor, is electrically connected in series to the laser and the chip capacitor as a whole, and includes a first terminal and a second terminal; a solder or a conductive adhesive that directly bonds the first terminal of the chip inductor and the chip capacitor to each other; an electrical wiring group in which the laser, the modulator, the chip capacitor, and the chip inductor are electrically connected to each other; and a substrate on which the laser, the modulator, the chip capacitor, and the chip inductor are mounted.

An optical transmitter capable of significantly suppressing a fluctuation in frequency response characteristics due to a fabrication error in internal wire length while reducing a subcarrier size of a module of the optical transmitter is provided. The optical transmitter includes: a subcarrier on which an RF wiring board, a modulated laser chip, and a terminating resistor are mounted and which has a ground pad on an upper surface thereof; and a wire for electrically connecting at least the RF wiring board and the modulated laser chip to each other, wherein the RF wiring board and the modulated laser chip are arranged in a width direction of the subcarrier, and a length of the wire in an electric path which starts at the RF wiring board, passes through the terminating resistor, and reaches the ground pad is 0.5 to 1.5 mm or an inductance of the wire is 0.4 to 1.2 nH.