Diode-laser-pump module with integrated signal ports for pumping amplifying fibers and method

An optical coupling method for modular apparatus, the method comprising:

• providing an enclosure, wherein the enclosure has a first external port and a second external port;
• providing a first delivery fiber connected to the first port;
• providing a first gain fiber, wherein a first end of the first gain fiber is connected to the delivery fiber, wherein the first gain fiber is outside the enclosure;
• and within the enclosure:
• generating laser pump light from a plurality of laser diodes that are within the enclosure;
• stabilizing the pump light using at least one grating;
• collimating the pump light from the plurality of laser diodes into a collimated pump-light beam, wherein the pump light in the collimated pump-light beam has a characteristic first wavelength;
• directing the pump light inside the enclosure from the collimated pump-light beam to exit the enclosure into the delivery fiber via the first external port;
• receiving signal light coming from the delivery fiber outside the enclosure through the first external port, wherein the signal light has a characteristic second wavelength different than the first wavelength;
• and
• directing the signal light inside the enclosure between the first external port and the second external port such that light derived from the signal light exits the enclosure via the second external port;
• and
• coupling a seed signal having the second wavelength to a second end of the first gain fiber such that the seed signal and the pump light counter-propagate in the first gain fiber;
• and
• amplifying the seed signal in the first gain fiber using power from the pump light.

An optical coupling method for modular apparatus, the method comprising:

• providing an enclosure, wherein the enclosure has a first external port and a second external port;
• connecting a first delivery fiber to the first port;
• connecting a first end of a first gain fiber to the delivery fiber, wherein the first gain fiber is outside the enclosure;
• and
• within the enclosure:
• generating laser pump light from one or more laser diodes that are within the enclosure;
• collimating the pump light from the one or more laser diodes into a collimated pump-light beam, wherein the pump light in the collimated pump-light beam has a characteristic first wavelength;
• directing the pump light inside the enclosure from the collimated pump-light beam to exit the enclosure via the first external port such that the pump light propagates through the delivery fiber to the gain fiber, and signal light from the gain fiber propagates through the delivery fiber to the first external port;
• receiving the signal light coming from outside the enclosure through the first external port, wherein the signal light has a characteristic second wavelength different than the first wavelength;
• directing the signal light inside the enclosure between the first external port and the second external port such that light derived from the signal light exits the enclosure via the second external port;
• and
• coupling signal feedback having the second wavelength to the first gain fiber such that lasing occurs in-the first gain fiber using power from the pump light.

A modular optical coupling apparatus comprising:

• an enclosure, wherein the enclosure has a first external port and a second external port;
• a plurality of laser diodes held within the enclosure, and configured to output pump light;
• a beam shaper held within the enclosure and optically coupled to receive pump light from the plurality of laser diodes and to provide a collimated pump-light beam, wherein the pump light in the collimated pump-light beam has a characteristic first wavelength;
• at least one stabilization grating located in an optical path between the plurality of laser diodes and the beam shaper and configured to stabilize the pump light;
• a first wavelength-selective optical element configured to direct pump light inside the enclosure from the collimated pump-light beam to the first external port and to direct signal light inside the enclosure between the first external port and the second external port, wherein the signal light has a characteristic second wavelength different than the first wavelength;
• a delivery fiber outside the enclosure, wherein a first end of the delivery fiber is connected to the first port;
• and
• a first gain fiber outside the enclosure, wherein a first end of the first gain fiber is connected to a second end of the delivery fiber.

A modular optical-coupling apparatus comprising:

• an enclosure, wherein the enclosure has a first external port and a second external port;
• one or more laser diodes held within the enclosure;
• a beam shaper held within the enclosure and optically coupled to receive pump light from one or more laser diodes and to provide a collimated pump-light beam, wherein the pump light in the collimated pump-light beam has a characteristic first wavelength;
• a first wavelength-selective optical element configured to direct pump light inside the enclosure from the collimated pump-light beam to exit the enclosure through the first external port and to direct signal light inside the enclosure between the first external port and the second external port, wherein the signal light has a characteristic second wavelength different than the first wavelength;
• a delivery fiber outside the enclosure, wherein a first end of the delivery fiber is directly connected to the first port;
• a first gain fiber outside the enclosure, wherein a first end of the first gain fiber is connected to a second end of the delivery fiber;
• and
• a seed-signal source that supplies a seed signal having the second wavelength to a second end of the first gain fiber such that the seed signal and the pump light counter-propagate in the first gain fiber, and wherein the apparatus is configured to amplify the seed signal in the first gain fiber using power from the pump light.

A modular optical coupling apparatus comprising:

• an enclosure, wherein the enclosure has a first external port and a second external port;
• a plurality of laser diodes held within the enclosure;
• means for combining laser light from the plurality of laser diodes into a collimated pump-light beam;
• means for directing pump light inside the enclosure from the collimated pump-light beam to exit the enclosure through the first external port, and wherein the means for directing of pump light inside the enclosure includes means for wavelength-selective transmitting the collimated pump-light beam towards the first port;
• a delivery fiber located external to the enclosure and configured to couple the pump light from the first external port to a gain fiber and to couple signal light from the gain fiber to the first eternal port, wherein the delivery fiber is connected to the first external port;
• and
• means for directing signal light inside the enclosure between the first external port and the second external port, wherein the signal light has a characteristic second wavelength different than the first wavelength, wherein the means for directing of signal light inside the enclosure includes means for wavelength-selective reflecting of signal light from the first port towards the second port.

A modular optical coupling apparatus comprising:

• an enclosure, wherein the enclosure has a first external port and a second external port;
• a plurality of laser diodes that are held within the enclosure and that generate pump light;
• means for stabilizing the pump light using at least one grating;
• means for collimating the pump light from the the plurality of laser diodes into a collimated pump-light beam, wherein the pump light in the collimated pump-light beam has a characteristic first wavelength;
• means for directing pump light inside the enclosure from the collimated pump-light beam to exit the enclosure through the first external port, wherein the means for directing pump light inside the enclosure is transmissive to pump light;
• means for directing signal light inside the enclosure between the first external port and the second external port, wherein the signal light has a characteristic second wavelength different than the first wavelength, wherein the means for directing signal light inside the enclosure is reflective to signal light;
• delivery-fiber means for coupling light between a first end of a first gain fiber outside the enclosure and the first port;
• means for coupling a seed signal having the second wavelength to a second end of the first gain fiber such that the seed signal and the pump light counter-propagate in the first gain fiber;
• and
• means for amplifying the seed signal in the first gain fiber using power from the pump light.

A modular optical coupling apparatus comprising:

• an enclosure, wherein the enclosure has a first external port and a second external port;
• one or more laser diodes held within the enclosure;
• means for collimating the pump light from the one or more laser diodes into a collimated pump-light beam, wherein the pump light in the collimated pump-light beam has a characteristic first wavelength;
• means for directing pump light inside the enclosure from the collimated pump-light beam to the first external port;
• delivery-fiber means for coupling the pump light from the first external port to a gain fiber and for coupling signal light from the gain fiber to the first eternal port, wherein the delivery-fiber means is external to the enclosure and is connected to the first external port;
• means for directing signal light inside the enclosure between the first external port and the second external port, wherein the signal light has a characteristic second wavelength different than the first wavelength;
• means for coupling signal feedback having the second wavelength to the first gain fiber;
• and
• means for lasing in the first gain fiber using power from the pump light.