Abstract: The present invention provides a structure that makes high-frequency transmission possible in an optical module and in the optical transmission apparatus using the module. The invention has means that excludes, from the service band of the optical module, frequency of the standing waves occurring at connection between the first high-frequency signal line substrate and second high-frequency signal line substrate in the optical module.

Abstract: The present invention is related to an optical communication module for transmitting high frequency signals (e.g., 10 Gbit/s and higher data rates) between an optical element and an external circuit. In an illustrative embodiment, the optical communication module includes signal transmission lines and ground lines formed on a ceramic substrate, a flexible wiring board, and a printed circuit board. The widths of the signal lines and the ground lines vary, as well as the spacing between the signal and ground lines. This facilitates characteristic impedance matching among the signal lines to within about 50?.

Abstract: A transmission line with a bending portion is provided, which line comprises any one of a coplanar line, another coplanar waveguide line formed on the dielectric substrate under which a ground layer is provided and a coplanar strip line. A chamfered portion is provided on the outer angular portion of the bending portion of the signal wiring conductor and a triangular conductor is disposed to an inner angular portion thereof. Given that length of the chamfered portion is defined as a, and length of the wiring edge side of the triangular conductor is defined as b and width of the signal wiring conductor is defined as c, it is arranged such that a is greater than b+c×square root of 2. Thereby, a transmission line or an optical module of smaller reflection loss at the bending portion thereof and of improved high-frequency characteristics is provided.

Abstract: A semiconductor laser and an optical fiber are optically coupled via a first lens and a second lens, the second lens is previously fixed to a module package and these parts are mounted to the module package, when focal lengths of the first lens and the second lens are respectively designated by f1 and f2, an optical distance between a principal plane of the first lens on its side of the second lens and a principal plane of the second lens on its side of the first lens, is made substantially equal to f1+f2. Thereby, there is provided an optical transmission module having low price capable of achieving a high coupling efficiency with high yield.

Abstract: The present invention provides an optical transmission module comprising: a laser diode; a lens for condensing a laser beam from the laser diode; a fiber ferrule which is placed so that the laser beam condensed by the lens can enter a fiber core; and a lens aperture or a lens aperture portion which is provided at one of the lens itself, a position before the lens and a position after the lens. In addition, the present invention provides an optical transmission module in which instead of the lens aperture, an effective diameter of the lens on the fiber ferrule side is set at a value ranging from 0.1 times to less than 0.2 times of a distance between an emittance plane of the lens and an incidence plane of the fiber ferrule.

Abstract: The present invention provides an optical module, and an optical transmission line comprising the optical module. The optical module has a structure in which an optical-modulator-mounted carrier is formed of a semiconductor substrate; a transmission line on the carrier is formed of a coplanar waveguide; a transmission line for inputting a signal into the transmission line is formed on a dielectric substrate; the transmission line on the input side which is a grounded coplanar waveguide is coupled by a conversion line to the transmission line on the output side which is a coplanar waveguide; and an electrical connection between the transmission lines is made by use of a conductor wire.

Abstract: The present invention relates to an optical transmission module comprising two substrates, each of which has an electronic part mounted on the substrate and a terminal area for inputting/outputting an electric signal into/from the electronic part, wherein an electrical connection is made between the terminal areas of said two substrates by use of a flexible substrate having a structure constituted of at least three layers, and thereby a high frequency signal is transmitted between the electronic part mounted on one substrate and the electronic part mounted on the other substrate through the flexible substrate while confining an electromagnetic field. In addition, the present invention provides an optical transmission module characterized in that a slit formed in a ground plane on a connection section of a three-layer flexible substrate reduces a disturbance in electromagnetic field, making it possible to improve the transmission characteristic of a high frequency signal.

Abstract: A laser diode module includes a laser diode device, a first photo detector part for receiving, first divided light that is a first portion of light when at least one of light emissions of the laser diode device is divided into two portions of light each traveling a different optical path, a second photo detector part for receiving second divided light that is a second portion of light thus divided via at least a wavelength selective member, and a controller which controls the lasing wavelength of the laser diode device on the basis of outputs of the first and second photo detector parts. A beam splitter provided between the laser diode and the wavelength selective member divides light emitted from the laser diode into the first and second divided light and a quarter-wave plate is provided in an optical path between the beam splitter and the wavelength selective member.

Abstract: The present invention provides a structure that makes high-frequency transmission possible in an optical module and in the optical transmission apparatus using the module. The invention has means that excludes, from the service band of the optical module, frequency of the standing waves occurring at connection between the first high-frequency signal line substrate and second high-frequency signal line substrate in the optical module.

Abstract: The present invention provides an optical module and a method for manufacturing the optical module, in which a V-shaped or trapezoidal groove having a first slope and a second slope facing to the first slope is formed at the surface of a silicon substrate by anisotropic etching, an adhesive is applied to a portion of at least the second slope in a region except the first slope of the groove, and lens is fixedly put in the groove.

Abstract: A beam spot size enlarger waveguide for enlarging the beam spot size is connected to a beam spot size reducer waveguide for shrinking the beam spot size, along with the direction of the propagation of light beam; or the beam spot size enlarger waveguide, a beam spot size maintainer waveguide for maintaining the beam spot size constantly, and the beam spot size reducer waveguide are connected in the direction of the propagation of light beam.

Abstract: An optical module for use in detecting a plurality of different wavelengths by making use of the multiple wavelength selectivity of an etalon. The optical module includes a semiconductor laser, a lens for converting a beam emitted from the semiconductor laser into a substantially parallel beam, a beam splitter for splitting the converted beam into a reflected beam and a transmitted beam, and a light-receiving element disposed such that one of the split beams is incident thereupon through an etalon, wherein a center of the reflected beam from the etalon occurring as the beam is incident upon the etalon is arranged to return to a region other than a beam-emitting portion of the semiconductor laser.

Abstract: An optical transmission module with an optical device mounted in a substrate provided with an optical waveguide is provided wherein respective metallic electrodes in pair are symmetrically disposed in each side of an optical device divided by a centerline parallel to an optical axis such that those electrodes have an error of 60 ?m or less and said metallic electrodes are soldered to a metallic electrode as disposed on a substrate, which electrode has a size enough to cover those electrodes as disposed in the optical device.

Abstract: According to the present invention there are provided a transmission line and an optical module having the transmission line, the transmission line having on a dielectric substrate a first signal wiring conductor, a second signal wiring conductor insulated from the first signal wiring conductor, a first electrode disposed near the first and second signal wiring conductors, a second electrode disposed near the second signal wiring conductor, and a ground wiring conductor disposed in adjacency to the second electrode, wherein a passing frequency band can be changed by changing the connection of conductor wires.

Abstract: The present invention relates to an optical transmission module comprising two substrates, each of which has an electronic part mounted on the substrate and a terminal area for inputting/outputting an electric signal into/from the electronic part, wherein an electrical connection is made between the terminal areas of said two substrates by use of a flexible substrate having a structure constituted of at least three layers, and thereby a high frequency signal is transmitted between the electronic part mounted on one substrate and the electronic part mounted on the other substrate through the flexible substrate while confining an electromagnetic field.

Abstract: The present invention provides an optical module, and an optical transmission line comprising the optical module. The optical module has a structure in which an optical-modulator-mounted carrier is formed of a semiconductor substrate; a transmission line on the carrier is formed of a coplanar waveguide; a transmission line for inputting a signal into the transmission line is formed on a dielectric substrate; the transmission line on the input side which is a grounded coplanar waveguide is coupled by a conversion line to the transmission line on the output side which is a coplanar waveguide; and an electrical connection between the transmission lines is made by use of a conductor wire.

Abstract: The present invention provides an optical module and a method for manufacturing the optical module, in which a V-shaped or trapezoidal groove having a first slope and a second slope facing to the first slope is formed at the surface of a silicon substrate by anisotropic etching, an adhesive is applied to a portion of at least the second slope in a region except the first slope of the groove, and lens is fixedly put in the groove.

Abstract: In aiming at cost lowering of an optical module and an optical transmission apparatus and with the objective of providing a semiconductor light receiving element that has a good coherence with the other edge emitting/incidence type optical devices and is capable of performing the positioning easily and with a high accuracy, in the edge emitting/incidence type light receiving element in which the light absorbing layer 19 has been formed, the space region is formed so as to provide at least 100 &mgr;m2 of the marker detecting region 24, thereby facilitating detection of marker 23 on the optical device 26 and executing the positioning of the light receiving element with a high accuracy, the space region resulting from eliminating a part of the light absorbing layer 19 that absorbs the detection light of the light receiving element, the transmission amount of the detection light toward the marker detecting region that is parallel to a primary plane being equal to 30% or higher, the detection light having penetrat

Abstract: A laser diode module includes a laser diode device, a first photo detector part for receiving, first divided light that is a first portion of light when at least one of light emissions of the laser diode device is divided into two portions of light each traveling a different optical path, a second photo detector part for receiving second divided light that is a second portion of light thus divided via at least a wavelength selective member, and a controller which controls the lasing wavelength of the laser diode device on the basis of outputs of the first and second photo detector parts. A beam splitter provided between the laser diode and the wavelength selective member divides light emitted from the laser diode into the first and second divided light and a quarter-wave plate is provided in an optical path between the beam splitter and the wavelength selective member.

Abstract: A PD (20) is mounted to a position offset (23) as viewed in the direction orthogonal to the center of an optical axis (14) of backward light (13) of an LD (11) in such a manner that a light receiving plane (21) thereof becomes substantially parallel to the center of the optical axis. Alternatively, the PD (20) is mounted thereto so that the light receiving plane of the PD is inclined at angles ranging from about 0° to about 30° to the center of the optical axis of the backward light. Further, the PD whose side face on the LD side is inclined, is used to repeatedly reflect the backward light between the PD and an LD mounting substrate, after which the backward light is launched on the light receiving plane 21.