Patent · US Expired

Optical communications module

US5677779A · kind A · utility

24Cited by
9References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 1995
Grant dateOct 14, 1997
Priority date
Expiry dateFeb 28, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B10/40
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A compact, low-cost combined transmitting/receiving optical communications module, which is suitable for use in a TCM system and which is capable of normal operation over a particularly wide temperature range in optical communications equipment, is provided. The optical transmitting/receiving section for this purpose has a laser diode which outputs a transmitted optical signal, a combined monitor/receiving photodiode which not only monitors the optical output signal from the laser diode during a transmitting period, but also receives the input optical signal from the transmission path during the receiving period, and an optical mixer/divider which performs transmitting/receiving mixing and dividing between the transmission path, the laser diode, and the photodiode. A drive section has a transmitting/receiving switching circuit which performs time-division transmitting/receiving switching and a threshold control circuit which performs successive control of the bias current of the laser diode so that the optical noise output monitored by the photodiode is maximized.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.