Patent ID: 6147795
Filing Date: 2000-11-14
Classification: H01S

Abstract:
A method of upgrading an existing erbium-doped fiber amplifier (EDFA) system including an erbium fiber contained in an environment to maintain the erbium fiber at a temperature above a predetermined minimum temperature value, the EDFA system having a pump laser efficiently operable below a predetermined maximum temperature value for driving the erbium fiber, a temperature sensor for sensing the temperature of the pump/laser, a control circuit electrically connected to the temperature sensor for generating operating current in response to a value of the sensed temperature, and a thermo-electric cooler (TEC) thermally connected to the pump laser for cooling the pump laser when the sensed temperature exceeds the maximum temperature value, the method comprising the steps of:connecting a heater across the TEC and positioning said heater in thermal contact with the erbium fiber for heating the fiber when the sensed temperature falls below the minimum temperature value; andproviding the operating current to said heater when the sensed temperature is below the minimum temperature value for heating the fiber, and providing the operating current to the TEC when the sensed temperature exceeds the maximum temperature value for cooling the laser.