Abstract: A triple resin layered optoelectronic module having an inner fluid or gelled resin having a refractive index which is equal to the refractive index of the fiber/waveguide at a temperature between −40° C. and +85° C. for covering the interval between the fiber/waveguide and the LD/PD chip, a medium resin with elasticity for protecting the inner resin, and an outer resin with rigidity for covering and protecting the medium resin, the substrate, the LD/PD chip and the lead frame. A cavity temporally stores the fluid inner resin for preventing the inner resin from flowing away with a help of surface tension.

Abstract: An optical receiver, small and inexpensive, is used for a WDM transmission system in place of a wavelength demultiplexer. In the receiver, a light-transmitting medium and a photodiode (PD) are placed on the same substrate, a wavelength-selecting filter is attached perpendicularly or obliquely to the end face of or to a cut section at the midpoint of the medium, the filter transmits only the assigned wavelength included in the incident light having multiplexed wavelengths, and the PD detects only the assigned wavelength. With an optical fiber, the fiber can be housed in a ferrule. In this case, the filter is inserted into a filter-supporting hole provided at a midpoint of the ferrule, the ferrule is fixed in a groove formed on the substrate, and an optical pathway-changing groove formed on the substrate reflects light having emerged from the optical fiber to introduce it into the PD.

Abstract: An LD/PD module having a main silicon substrate having a cavity, a transmitting portion having an LD and an LD driving IC which is directly mounted upon the main silicon substrate, and a receiving portion having a PD and an amplifier which is indirectly mounted upon the main silicon substrate via an auxiliary insulating substrate embedded in the cavity. The auxiliary insulating substrate suppresses current-induced crosstalk from the transmitting portion to the receiving portion.

Abstract: An LD module comprising a substrate, an LD, an LD driving IC and a monitoring PD mounted in this order on the substrate, wirings for connecting the LD to the IC, and a light guiding device provided below the IC for guiding the LD light to the monitoring PD by detouring the LD light beneath the LD driving IC.

Abstract: The present invention relates to a high-sensitivity top-electrode and bottom-illuminated type photodiode. The device consists of a highly doped buffer layer, a photo-detecting layer on a semi-insulating substrate. An electrode is formed on the conductive domain that is formed in the photo-detecting layer, and another electrode is formed on the partly exposed peripheral area of the highly-doped buffer layer by removing a part of the photo-detecting layer. As the semi-insulating substrate absorbs less light in the substrate, a decrease of sensitivity by the substrate absorption can be prevented.

Abstract: The PD/LD module of the present invention comprises a platform, a straight light guide (waveguide) formed on the platform for guiding transmitting light and receiving light, a light source (LD or LED) positioned at an end of the light guide for emitting transmitting light, a PD mounted just above the light guide for detecting receiving signals and a filter sloping upward on the way of the light guide for reflecting receiving light to the photodiode (PD) and passing transmitting light.

Abstract: An optical communication device having an optical fiber, other optical parts, a transparent potting resin with a refractive index akin to the fiber and a pressurizing element with extra pressure in contact with the potting resin for applying positive pressure upon the potting resin with a predetermined temperature range. The present optical communication device can solve the problems of decline of sensitivity of PDs and instability of the oscillation of LDs in a low temperature region between −40° C. and 0° C. after a heat cycle test.

Abstract: A photodiode that is used in an optical communication system using two different wavelengths, &lgr;1 and &lgr;2(&lgr;1<&lgr;2), and that enables a reduction in the optical crosstalk caused by outgoing light having a longer wavelengths, &lgr;2. A photodiode that receives light having a shorter wavelengths, &lgr;1, is provided with an absorption layer made of a material having a bandgap wavelength, &lgr;g(&lgr;1<&lgr;g<&lgr;2), to detect the light having &lgr;1. A filter layer that absorbs unwanted light having &lgr;2 is provided over the absorption layer so that the light having &lgr;2 cannot return to the absorption layer after passing through it once.

Abstract: A photodiode which senses only &lgr;2 without WDM in optical communication systems containing two signals of different wavelengths &lgr;1 and &lgr;2. The photodiode has a filter layer whose band gap wavelength &lgr;g satisfies an inequality of &lgr;1<&lgr;g<&lgr;2 for annihilating &lgr;1. For vanishing tails of signals, the peripheral pn-junction is formed around the central pn-junction. In the case, an n-electrode is mounted on both the peripheral p-region and the peripheral n-region.

Abstract: An LD module having a spot-size conversion LD for emitting a beam of a small aperture angle, an optical fiber or a waveguide and a lens for converging the LD beam to the fiber or the waveguide.

Abstract: Simultaneous bidirectional transmission type LD/PD module having a substrate, a signal transmitting part mounted on the substrate, a signal receiving part formed on the substrate, an end of a fiber communicating with a base station, a light waveguide coupling the fiber to the transmitting part and the receiving part, a filter separating the receiving signal light from the transmitting signal light and a resin mold package containing the substrate, the transmitting part, the receiving part, the filter and the lead frame. The receiving part is electromagnetically shielded with multihole metal members from the noise generated by the transmitting part. The resin penetrates through the holes and fully covers the receiving part.

Abstract: A triple resin layered optoelectronic module having an inner fluid or gelled resin having a refractive index which is equal to the refractive index of the fiber/waveguide at a temperature between −40° C. and +85 ° C. for covering the interval between the fiber/waveguide and the LD/PD chip, a medium resin with elasticity for protecting the inner resin, and an outer resin with rigidity for covering and protecting the medium resin, the substrate, the LD/PD chip and the lead frame. A cavity temporally stores the fluid inner resin for preventing the inner resin from flowing away with a help of surface tension.

Abstract: The object is to provide an optical module for optical transmission which has a double resin structure wherein a transparent resin and a fixing resin are combined, which is low in price, and is easily produced. A package with a inside-and-outside double structure comprising an inner container having barriers filled with a transparent resin and a hard outer container formed of a fixing resin. The inner container stores the highly fluid transparent resin and prevents it from flowing out. The outer container provides mechanical strength and airtightness.

Abstract: A transmitting and receiving module helps reduce electrical crosstalk and noise during transmitting and/or receiving signals. Electrical isolation among metallized electrodes in a surface-mounted module with an optical fiber and an optical device can be achieved by using a low resistivity Si substrate, providing ground terminals on the surface of the Si substrate, and grounding the Si substrate. Noise and crosstalk during transmitting and receiving signals can be reduced by providing a copper contact adhered to the bottom surface of the Si substrate and by grounding.

Abstract: A PD module including a planar substrate, a first V-groove formed in the longitudinal direction on the substrate, a path-changing groove formed in the lateral direction vertically to the first V-groove on the substrate for ensuring a space at an extension of the first V-groove, an optical fiber fixed in the first V-groove for guiding signal light, a slanting reflection plane formed at the front wall of the path-changing groove for reflecting the light emanating from the fiber, a PD chip with a width B and a length C mounted on three spots of the substrate over the path-changing groove, the PD lying above the path-changing groove and the slanting reflection plane, a transparent adhesive with a refractive index similar to the fiber being supplied to a space including the end of the fiber, the path-changing groove and the bottom of the PD chip, and a fixation adhesive supplied on the first V-groove and on the transparent adhesive for fixing the fiber to the first V-groove, the light emanating from the fiber bein

Abstract: The module has a planar platform. A straight light guide is formed on the planar platform for guiding incoming light and outgoing light. A filter is interposed slantingly in the light guide for reflecting a part of light propagating in the light guide but for allowing the rest of the light to pass through. An LD or LED is mounted at an extension of the light guide for producing sending signal light and introducing the sending light into the light guide. A photodiode is mounted on the platform at a point on a path of the reflected light for sensing the incoming (receiving signal) light. Guide pins are fixed to the platform for attaching to and detaching from an optical connector having holes and an optical fiber. In the attached state, the end of the light guide of the module faces the end of the fiber in the connector.

Abstract: A half-transmittance photodiode usable as a photodetector in receivers for “ping-pong transmission” is improved in temperature characteristic, so that a half-transmittance photodiode usable at low temperatures is available. A p-n junction is formed in a buffer layer, not in an absorption layer.

Abstract: A photodiode which senses only .lambda.2 without WDM in optical communication systems containing two signals of different wavelengths .lambda.1 and .lambda.2. The photodiode has a filter layer whose band gap wavelength .lambda.g satisfies an inequality of .lambda.1<.lambda.g<.lambda.2 for annihilating .lambda.1. For vanishing tails of signals, the peripheral pn-junction is formed around the central pn-junction. In the case, an n-electrode is mounted on both the peripheral p-region and the peripheral n-region.

Abstract: A low-capacitance package having a wide hole, an L-shaped lead pin, other linear lead pins, an insulating material filling in the hole for fixing the L-shaped lead pin and another pin in the hole. Projecting from the hole, the horizontal part of the L-shaped pin is separated from the insulating material and stands higher than the surface of the package. A semiconductor device chip is fixed directly on the horizontal part of the L-shaped pin.

Abstract: This invention provides an analog PD module useful for a large number of channels and a digital PD module useful for a large power signal input because of its reduced distortion. The PD chip is fixed at a spot deviating by L tan .alpha. from the lens center in the direction of a projection of a vector TS from the highest edge (T) to the lowest edge (S), where L is the distance between the lens center and the PD. The fiber should deviate in the contrary direction. The orientation enables a beam emanating from the fiber end to pass the center of the lens and reach the PD by spreading on a direct line.