Fujitsu Corporation

Fujitsu Optical Components Limited

Masaki Kunii

Kazuya Sasaki

Tetsuya Yamada

Shinichi Sakuramoto

Masakazu Horishita

Hirokazu Osada

Masami Kamioka

Tsutomu Ohtsu

Shin-ichi Sakuramoto

Masanari Yamakita

An optical transceiver includes a single-fiber bidirectional optical transmission/reception device, a circuit board, a transmission-side FPC, a reception-side FPC and a separation wall. The optical transceiver includes a single-fiber bidirectional optical transmission/reception device includes an LD stem that converts an electric signal into an optical signal and transmits it, and a PD stem that receives the optical signal and converts it into an electric signal. The transmission-side FPC electrically connects the LD stem and the circuit board. The reception-side FPC electrically connects the PD stem and the circuit board. The separation wall is formed between the transmission-side FPC and the reception-side FPC, and grounded to the chassis of the optical transceiver. The reception-side FPC is folded and set between the chassis and the separation wall such that the board front surface is an inner side, where the micro-strip line is formed on the above board front surface.

Optical transceiver and production method thereof

A single-fiber bidirectional optical transmitter/receiver includes a single-fiber bidirectional optical transmission/reception device. A circuit board has a signal processing circuit and a drive circuit configured to drive the single-fiber bidirectional optical transmission/reception device. A main housing accommodates the single-fiber bidirectional optical transmission/reception device and the circuit board. A ground part of a reception side of the single-fiber bidirectional optical transmission/reception device is electrically connected to a ground part of a transmission side of the single-fiber bidirectional optical transmission/reception device through a ground wiring pattern formed on a flexible printed board.

Single-fiber bidirectional optical transmitter/receiver

An optical transmitting/receiving apparatus capable of suppressing electrical crosstalk and magnetic crosstalk, includes: a laser diode/photo diode (LD/PD) integrated module that terminates a single-core bidirectional optical fiber; a circuit board electrically connected to a lead pin led out of the LD/PD integrated module; and a plastic case that accommodates the circuit board. At least a part of the plastic case abuts against the LD/PD integrated module, and impedance of the plastic case is controlled by mixing a conductive filler into the plastic case.

Optical transmitting/receiving apparatus

A preamplifier circuit, a clock switching circuit, and an optical receiver are provided that include a preamplifier that controls a bandwidth for conducting amplification on an input signal by varying a feedback resistance according to a control signal; a control signal generating part that determines the band of the output signal of the preamplifier to generate the control signal; and a correction signal generating part that generates a correction signal for correcting the control signal; wherein the correction signal corrects the control signal to adjust the feedback resistance. Accordingly, even when the number of rises and falls of an optical input signal in a given time period is less than a predetermined number range, the control signal may be properly generated to successfully conduct band control. Thus, an optical receiver that is not dedicated to a predetermined input signal pattern but is rather capable of automatically adjusting its bandwidth may be realized, and the cost of manufacturing the optical receiver structure may be reduced.

Preamplifier circuit, clock switching circuit, and optical receiver

Growing community of inventors

Yokohama, Japan

Masaki Kunii